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A comparative study of robotic and laparoscopic approaches to Heller myotomy

      Abstract

      Objective

      Minimally invasive Heller myotomy for achalasia is commonly performed laparoscopically, but recently done with robotic assistance. We compare outcomes of the 2 approaches.

      Methods

      From January 2010 to January 2020, 447 patients underwent Heller myotomy with anterior fundoplication (170 with robotic assistance and 277 laparoscopically). End points included short-term and longitudinal esophageal emptying according to timed barium esophagram, symptom relief according to Eckardt score, and time-related reintervention. Normal esophageal morphology, present in 328 patients, was defined as nonsigmoidal with width <5 cm. We performed a propensity score--matched analysis to evaluate outcomes among robotic and laparoscopic groups.

      Results

      Timed barium esophagrams showed complete emptying at 5 minutes in 58% (77/132) of the robotic group and 48% (115/241) of the laparoscopic group in the short term (within 6 months of surgery). In the propensity-matched patients with normal esophageal morphology, the robotic group had a higher longitudinal prevalence of complete emptying of barium at 5 minutes (54% vs 34% at 4 years; P = .05), better intermediate-term Eckardt scores (1.7% vs 10% > 3 at 4 years; P = .0008), and actuarially fewer reinterventions (1.2% vs 11% at 3 years; P = .04).

      Conclusions

      Both robotically assisted and laparoscopic Heller myotomy had excellent outcomes in patients treated for achalasia. In a matched subgroup of patients with normal esophageal morphology within this heterogeneous disease, the robotic approach might be associated with greater esophageal emptying, palliation of symptoms, and freedom from reintervention in the intermediate term. Long-term analysis would be important to determine if this trend persists.

      Graphical abstract

      Key Words

      Abbreviation and Acronym:

      POEM (per-oral endoscopic myotomy)
      Figure thumbnail fx2
      Prevalence of esophageal emptying: robotic (blue) and laparoscopic (red) Heller myotomy.
      Robotically assisted and laparoscopic Heller myotomy provide durable palliation of achalasia symptoms, and in select patients the robotic approach may be superior to the laparoscopic approach.
      Although the robotic platform has been deemed noninferior to laparoscopic Heller myotomy, our study suggests that it might improve outcomes in the surgical treatment of achalasia. Although achalasia patients are heterogeneous, comparisons in a small, matched patient subgroup showed greater emptying and palliation. Given the ubiquitous adoption of robotic platforms, randomized trials are unlikely.
      Achalasia is a rare motility disorder of the esophagus that causes aperistalsis of the esophageal body and abnormal relaxation of the lower esophageal sphincter.
      • Sadowski D.C.
      • Ackah F.
      • Jiang B.
      • Svenson L.W.
      Achalasia: incidence, prevalence and survival. A population-based study.
      For patients otherwise fit, a minimally invasive Heller myotomy with a partial fundoplication is the gold standard surgical treatment. A laparoscopic approach to this procedure has been widely adopted, with excellent clinical outcomes.
      • Costantini M.
      • Salvador R.
      • Capovilla G.
      • Vallese L.
      • Costantini A.
      • Nicoletti L.
      • et al.
      A thousand and one laparoscopic Heller myotomies for esophageal achalasia: a 25-year experience at a single tertiary center.
      • Costantino C.L.
      • Geller A.D.
      • Visenio M.R.
      • Morse C.R.
      • Rattner D.W.
      Outcomes of laparoscopic Heller myotomy for achalasia: 22-year experience.
      • Fukushima N.
      • Masuda T.
      • Yano F.
      • Omura N.
      • Tsuboi K.
      • Hoshino M.
      • et al.
      Over ten-year outcomes of laparoscopic Heller-myotomy with Dor-fundoplication with achalasia: single-center experience with annual endoscopic surveillance.
      • Doubova M.
      • Gowing S.
      • Robaidi H.
      • Gilbert S.
      • Maziak D.E.
      • Shamji F.M.
      • et al.
      Long-term symptom control after laparoscopic Heller myotomy and Dor fundoplication for achalasia.
      As is the case with other procedures,
      • Sepehripour A.H.
      • Garas G.
      • Athanasiou T.
      • Casula R.
      Robotics in cardiac surgery.
      • Jeong W.
      • Kumar R.
      • Menon M.
      Past, present and future of urological robotic surgery.
      • Moon A.S.
      • Garofalo J.
      • Koirala P.
      • Vu M.T.
      • Chuang L.
      Robotic surgery in gynecology.
      a robotic approach has recently gained traction, and its role has evolved in foregut surgery. These robotic approaches have often been shown to be noninferior to standard laparoscopic/thoracoscopic treatment modalities. However, because of the higher costs of the robotic platform and lack of haptic feedback, added value has not been clearly established.
      • Leal Ghezzi T.
      • Campos Corleta O.
      30 Years of robotic surgery.
      Despite increasing use, there is a paucity of data to support the superiority of one approach over the other. Our objective was to compare our experience with the 2 techniques over the past decade to determine the added value, if any, of the robotic platform over conventional laparoscopic Heller myotomy in treating patients with achalasia.

      Methods

      Patients

      From January 1, 2010, to January 1, 2020, 447 adults underwent primary Heller myotomy with anterior (Dor) fundoplication at Cleveland Clinic, 170 (38%) with robotic assistance and 277 (62%) laparoscopically. Patients who underwent Heller myotomy with no fundoplication or other type of fundoplication, and those having concomitant procedures, such as epiphrenic diverticulectomy and hiatal hernia repair, were excluded.
      Mean age in the robotic group was 50 ± 16 years, 92 (54%) were male, and body mass index was 26 ± 5.0 kg/m2; mean age in the laparoscopic group was 49 ± 16 years, 141 (51%) were male, and body mass index was 26 ± 5.4 kg/m2 (Table E1). Most patients in both groups had type II achalasia.
      • Kahrilas P.J.
      • Bredenoord A.J.
      • Fox M.
      • Gyawali C.P.
      • Roman S.
      • Smout A.J.
      • et al.
      The Chicago classification of esophageal motility disorders, v3.0.
      Thirteen patients (7.8%) in the robotic group and 36 (13%) in the laparoscopic group received botulinum toxin injections before surgery. Two patients (1.2%) in the robotic group and 26 (9.6%) in the laparoscopic group had previous pneumatic dilatations.

      Subgroup for Comparative Outcomes

      Of the 447 patients, a large subgroup of 328 patients (73%) had normal esophageal morphology, defined as nonsigmoidal with esophageal width <5 cm, and available timed barium esophagrams. This subgroup was the basis for comparative studies of outcomes using propensity score-matching. Of these, 122 (37%) underwent a robotically assisted Heller myotomy and 206 (63%) a laparoscopic operation.

      Comparative effectiveness

      Comparison of outcomes of robotically assisted and laparoscopic Heller myotomy is confounded by heterogeneity of the esophageal morphology in achalasia, patient characteristics, frequency of previous endoscopic interventions, sequential nature of the introduction of the robotic technique, and transition of surgeons. To partially mitigate these potentially confounding factors, we focused comparisons on the subgroup of patients with normal esophageal morphology and used propensity-score matching on characteristics of patients in this subgroup.

      Operative Technique

      Heller myotomy consists of an esophagogastric myotomy, frequently combined with an antireflux procedure such as a partial fundoplication (Video 1). Currently, we limit the dissection to the anterior aspect of the esophagus and perform the myotomy over a 60-French Maloney bougie for at least 4 cm on the esophagus and 3 cm on the stomach.
      The partial fundoplication used in this study was exclusively a modified Dor fundoplication. Our “3-stitch” Dor fundoplication is an effective addition to a minimally invasive Heller myotomy, with good palliation of symptoms and low occurrence of acid reflux.
      • Feczko A.F.
      • Murthy S.
      • Adhikari S.
      • Thota P.
      • Gabbard S.
      • Ahmad U.
      • et al.
      Minimally invasive “3-stitch” modification of the Dor fundoplication: simple and effective.
      The robotic approach is a 4-arm technique using the da Vinci Xi robotic platform (Intuitive Surgical). The laparoscopic approach uses a standard 5-port technique with a split table. The robotic approach substantially increased beginning in 2015 and the laparoscopic approach diminished (Figure 1).
      Figure thumbnail gr1
      Figure 1Number of robotic (blue) and laparoscopic (red) Heller myotomies per year.

      Data

      Baseline, procedural, and postprocedural data were abstracted from medical records and entered into the Achalasia Longitudinal Database in REDCap. Other electronic medical record databases were also queried. All data used for this study were approved for use in research by the institutional review board, with patient consent waived, number 4826, approved December 28, 2001, and renewed annually, with a current expiration date of December 31, 2022.

      End Points

      Outcomes were procedure time (defined as incision to dressings and only available from 2014) and perioperative complications; postoperative esophageal emptying assessed on timed barium esophagrams according to barium column width at 1 and 5 minutes
      • Neyaz Z.
      • Gupta M.
      • Ghoshal U.C.
      How to perform and interpret timed barium esophagogram.
      ; postoperative symptoms assessed according to Eckardt score,
      • Eckardt V.F.
      • Aignherr C.
      • Bernhard G.
      Predictors of outcome in patients with achalasia treated by pneumatic dilation.
      with treatment success defined as score ≤3; acid reflux assessed according to esophagitis on esophagogastroduodenoscopy and DeMeester score on postoperative 24- or 48-hour pH study (done within 6 months of intervention)
      • Johnson L.F.
      • Demeester T.R.
      Twenty-four-hour pH monitoring of the distal esophagus. A quantitative measure of gastroesophageal reflux.
      ,
      • Johnson L.F.
      • DeMeester T.R.
      Development of the 24-hour intraesophageal pH monitoring composite scoring system.
      ; and esophageal reintervention (pneumatic dilatation, per-oral endoscopic myotomy (POEM), redo Heller myotomy, or esophagectomy). Eckardt score was available only since 2014. For patients who underwent surgery before 2014, postoperative Eckardt scores were obtained during follow-up after 2014. When short-term follow-up is reported, it refers to the first timed barium esophagram and Eckhart score obtained between 1 and 6 months after surgery.
      Among propensity-matched patients with normal esophageal morphology (see “Comparative Effectiveness” earlier Methods), 69 in the robotic group and 73 in the laparoscopic group had 146 and 232 assessments of esophageal emptying according to timed barium esophagrams, respectively (Figure E1). Also among these propensity-matched patients, 48 of the robotic group and 47 of the laparoscopic group had 140 and 141 assessments of symptoms expressed on the Eckardt scale, respectively (Figure E2).
      For reinterventions, 50% of the entire robotic group was followed 17 months or more, 25% 2.3 years or more, and 10% 3.3 years or more; 50% of the entire laparoscopic group was followed 30 months or more, 25% 5 years or more, and 10% 7.7 years or more. Among propensity score-matched patients with normal esophageal morphology, 50% of the robotic group was followed 17 months or more, 25% 2.5 years or more, and 10% 3.7 years or more; 50% of the laparoscopic group was followed 27 months or more, 25% 5 years or more, and 10% 7 years or more.

      Data Analysis

      All analyses were performed using SAS software version 9.4 (SAS Institute). Continuous variables are summarized by mean ± standard deviation or the equivalent median [15th, 85th percentiles] if the distribution was skewed. Comparisons are made using the Wilcoxon rank-sum (nonparametric) test. Categorical data are summarized by frequencies and percentages, with the χ2 test used for comparisons. Uncertainty is expressed by confidence limits equivalent to ±1 standard error (68%).

      Esophageal emptying

      Because of the zero-inflated nature of timed barium esophagram data, we modeled the data as the probability of complete emptying. A multiphase, nonlinear, logistic mixed-effects model was used to resolve a number of time phases to form and implement a temporal decomposition model.
      • Rajeswaran J.
      • Blackstone E.H.
      • Ehrlinger J.
      • Li L.
      • Ishwaran H.
      • Parides M.K.
      Probability of atrial fibrillation after ablation: using a parametric nonlinear temporal decomposition mixed effects model.
      Difference in longitudinal pattern was assessed by forcing the robotic versus laparoscopic approach into each time phase of the model.

      Symptom relief

      A nonlinear cumulative logit mixed model was used to analyze the prevalence of individual Eckardt scores over time.
      • Rajeswaran J.
      • Blackstone E.H.
      • Ehrlinger J.
      • Li L.
      • Ishwaran H.
      • Parides M.K.
      Probability of atrial fibrillation after ablation: using a parametric nonlinear temporal decomposition mixed effects model.
      Difference in longitudinal pattern was assessed by forcing the robotic versus laparoscopic approach into the model.

      Reintervention

      Time-related occurrence of first reintervention was analyzed using the Kaplan–Meier estimator. Groups were compared using the log rank test.
      Multivariable logistic regression was performed first to identify factors associated with the robotic group (parsimonious model). Machine-learning variable selection used variables in Appendix E1 and 1000 bootstrap data sets for automated analysis with an inclusion criterion of P < .05, and the median rule for including variables in a final model (Table E2).
      • Breiman L.
      Bagging predictors.
      • Rajeswaran J.
      • Blackstone E.H.
      Identifying risk factors: challenges of separating signal from noise.
      This parsimonious model was augmented by additional factors (see variables with asterisks in Appendix E1) to form a semisaturated model from which a propensity score was calculated for each patient. These propensity scores were used to identify 82 well-matched patient pairs using a caliper of 0.2 times the standard deviation of the logit of the propensity score (Figure E3).
      • Austin P.C.
      Optimal caliper widths for propensity-score matching when estimating differences in means and differences in proportions in observational studies.
      Descriptive comparisons of the cohort subset before and after matching are shown in Table 1.
      Table 1Preoperative characteristics of subset of patients with normal esophageal morphology before and after propensity-score matching
      CharacteristicsBefore matchingAfter matching
      Robotic (N = 122)SMD, %Laparoscopic (N = 206)Robotic (N = 82)SMD, %Laparoscopic (N = 82)
      n
      Patients with data available.
      No. (%) or mean ± SDn
      Patients with data available.
      No. (%) or mean ± SDn
      Patients with data available.
      No. (%) or mean ± SDn
      Patients with data available.
      No. (%) or mean ± SD
      Demographics
       Female12256 (46)−7.2206102 (50)8238 (46)7.48235 (43)
       Race
      White120106 (88)2.4201176 (88)8070 (88)−0.938272 (88)
      Black1204 (3.3)−2820121 (10)802 (2.5)−34829 (11)
      Other12010 (8.3)292014 (2.0)808 (10)39821 (1.2)
       Age, y12248 ± 151320646 ± 168246 ± 14−7.48247 ± 15
       Height, cm122172 ± 9.64.2197171 ± 1082172 ± 9.58.278171 ± 10
       Weight, kg12278 ± 163.719977 ± 198278 ± 162.27978 ± 19
       BSA, m21221.9 ± 0.246.01971.9 ± 0.27821.9 ± 0.246.2781.9 ± 0.27
       BMI, kg/m212226 ± 5.04.119726 ± 5.48227 ± 5.01.17826 ± 5.6
      Preoperative
       Previous botulinum toxin injections1198 (6.7)−2520129 (14)807 (8.8)−4.7798 (10)
       Achalasia type1111947778
      I12 (11)−2841 (21)11 (14)4.310 (13)
      II89 (80)18141 (73)59 (77)−3.861 (78)
      III3 (2.7)−1310 (5.2)1 (1.3)−316 (7.7)
      EGJ outflow obstruction6 (5.4)252 (1.0)6 (7.8)321 (1.3)
      Other1 (0.90)130 (0)0 (0)0 (0)0 (0)
       ASA class1196020080−2.778
      I2 (1.7)8 (4.0)2 (2.5)1 (1.3)
      II24 (20)77 (39)22 (28)20 (26)
      III62 (52)102 (51)44 (55)47 (60)
      IV31 (26)13 (6.5)12 (15)10 (13)
      TBE
       Width at 1 min, cm1223.2 ± 1.2322062.8 ± 1.0823.1 ± 1.27.2823.0 ± 0.99
       Width at 5 min, cm1222.7 ± 1.3272062.3 ± 1.3822.5 ± 1.3−0.92822.6 ± 1.4
       Barium volume ≥250 mL12247 (39)−40205119 (58)8240 (49)−3.78141 (51)
       Barium volume, mL122176 ± 72−33205200 ± 6882193 ± 697.281188 ± 74
      Manometry
       IRP, mm Hg10825 ± 13−9.519926 ± 127426 ± 12−1.88126 ± 12
      SMD, Standardized mean difference; BSA, body surface area; BMI, body mass index; EGJ, esophagogastric junction; ASA, American Society of Anesthesiologists; TBE, timed barium esophagram; IRP, integrated relaxation pressure.
      Patients with data available.
      To account for missing values for some variables, fivefold imputation was performed using multivariate imputation by chained equations. Regression coefficients for final model variables and their variance–covariance matrix were estimated for each imputed data set and combined using Rubin's
      • Rubin D.B.
      Multiple Imputation for Non-Response in Surveys.
      method.

      Results

      Perioperative Outcomes

      Median procedure time was 121 [100, 150] minutes in the robotically assisted Heller myotomy group and 142 [115, 171] minutes in the laparoscopic group (Table E3). No patient in the robotic group experienced an intraoperative mucosal tear, whereas 5 (1.8%) in the laparoscopic group did. Perioperative complications were rare and included a delayed leak resolved with conservative management (n = 1) and an intra-abdominal hematoma requiring surgical exploration (n = 1), both in the laparoscopic group. Median length of stay was 1 day [1, 2] in both groups.

      Unmatched Short-Term Outcomes

      Esophageal emptying

      Timed barium esophagrams showed complete emptying at 5 minutes in 58% (77/132) of the robotic group and 48% (115/241) of the laparoscopic group in the short term (first study obtained within 6 months of surgery). Among patients with normal esophageal morphology, frequency of complete emptying in the robotic group was 66% (63/96) and in the laparoscopic group, 55% (99/179; Figure E4). Among patients with a sigmoid (end-stage) esophagus, frequency of complete emptying was 39% (14/36) in the robotic group and 26% (16/62) in the laparoscopic group. A small number of patients with normal esophageal morphology showed worsening at 5 minutes in the short term after robotically assisted (1%; 1/96) and laparoscopic (4.5%; 8/179) Heller myotomy. In the sigmoid esophageal morphology group, worsening of emptying occurred in no patient (0/26) in the robotic group and 19% (10/53) in the laparoscopic group.

      Symptom relief and acid reflux

      Short-term symptom palliation (Eckardt score ≤3) was 100% (143/143) in the robotic group and 98% (65/66) in the laparoscopic group. Abnormal postoperative pH study (DeMeester score >14.72) occurred in 15% (12/80) of the robotic group and 15% (22/144) of the laparoscopic group.

      Reintervention

      During follow-up, 4 patients in the robotic group and 59 in the laparoscopic group underwent pneumatic dilatation or surgery (Figure E5). In the robotic group (with a 17-month median follow-up), 3 patients underwent pneumatic dilatation and 1 a POEM. In the laparoscopic group (with a 30-month median follow-up), 39 patients underwent pneumatic dilatation and 20 surgical reintervention (reoperative Heller myotomy in 3, esophagectomy in 4, and POEM in 13).

      Propensity-Matched Comparisons

      Perioperative outcomes

      Among propensity-matched patients with normal esophageal morphology, there was no difference in length of stay between the robotic and laparoscopic groups (1 day [1, 2 days]; P = .4; Table 2). There were no mucosal perforations in the robotic group and 1 (1.2%) in the laparoscopic group. Postoperative length of stay was median 1 day in both groups.
      Table 2Perioperative and postoperative outcomes of subset of patients with normal esophageal morphology before and after propensity-score matching
      OutcomesBefore matchingAfter matching
      Robotic (N = 122)Laparoscopic (N = 206)PRobotic (N = 82)Laparoscopic (N = 82)P
      n
      Patients with data available.
      No. (%) or median [p15, p85]n
      Patients with data available.
      No. (%) or median [p15, p85]n
      Patients with data available.
      No. (%) or median [p15, p85]n
      Patients with data available.
      No. (%) or median [p15, p85]
      Perioperative
       Mucosal perforation1220 (0)2063 (1.5).3820 (0)821 (1.2)>.9
       Length of stay, d1221 [1, 2]2061 [1, 2].8821 [1, 2]821 [1, 2].4
      Short-term
       Esophageal emptying96179.106571.10
      Complete emptying63 (66)99 (55)42 (65)36 (51)
       Reflux/DeMeester score61105>.93739>.9
      Normal51 (84)88 (84)30 (81)32 (82)
      Abnormal10 (16)17 (16)7 (19)7 (18)
      p15, p85, 15th, 85th percentiles.
      Patients with data available.

      Esophageal emptying

      Complete emptying at 5 minutes in 65% (42/65) of the robotic group and 51% (36/71) of the laparoscopic group (P = .10) in the short term. However, longitudinally, prevalence of complete emptying at 5 minutes was 71% and 54% at 1 year and 54% and 34% at 4 years in the robotic versus laparoscopic groups, respectively (P = .05; Figure 2).
      Figure thumbnail gr2
      Figure 2Prevalence of complete emptying at 5 minutes on timed barium esophagrams after robotic (blue) and laparoscopic (red) Heller myotomy in propensity-matched patients with normal (straight) esophageal configuration. Solid lines represent the estimate of average barium column width enclosed within a 68% bootstrap percentile confidence interval. Symbols represent data grouped within time intervals, without regard to the repeated nature of the data, to provide a crude validation of model fit. Number of patients remaining at risk and number of timed barium esophagrams (TBEs) are depicted below the horizontal axis and in .

      Symptom relief

      Both groups had excellent short-term palliation (Eckardt score ≤3), 100% (48/48) in the robotic group and 98% (46/47) in the laparoscopic group. Longitudinal average trend of Eckardt score >3 during follow-up showed an early phase of rapidly improving symptom relief (predominantly before 6 months post-Heller myotomy) that merged into a constant phase (plateau) in the robotic group, but into a phase of increasing symptoms in the laparoscopic group (Figure 3). During the early phase, confidence limits of the 2 groups overlapped (P = .4). Thereafter, prevalence of patients with Eckardt scores <3 separated widely (P = .0008), with the robotic group having a higher likelihood of an Eckardt score ≤3 than the laparoscopic group. At 1 and 4 years, 1.6% and 1.7% of the robotic group had Eckardt scores >3, versus 6.3% and 10% of the laparoscopic group.
      Figure thumbnail gr3
      Figure 3Prevalence of Eckardt score >3 after robotic (blue) and laparoscopic (red) Heller myotomy in propensity-matched patients with normal esophageal morphology. Solid lines depict parametric estimates enclosed within a 68% confidence interval. Number of patients remaining at risk and number of Eckardt scores are depicted below the horizontal axis and in .

      Reintervention

      Fewer patients experienced a reintervention in the robotic group than in the laparoscopic group, accounting for the difference in duration of follow-up (Table E3). Actuarial estimates of reintervention were 1.2% in the robotic group at 1 and 3 years, and 0% and 11% at these times in the laparoscopic group (P = .04; Figure 4).
      Figure thumbnail gr4
      Figure 4First reintervention after robotic (blue) and laparoscopic (red) Heller myotomy in propensity-matched patients with normal esophageal morphology. Each symbol represents a reintervention, and vertical bars are asymmetric 68% confidence intervals equivalent to ±1 standard error.

      Discussion

      Principal Findings

      Excellent symptomatic relief after Heller myotomy was achieved regardless of approach. In a selected propensity-matched cohort of patients with normal esophageal morphology, comparing outcomes in the short and intermediate term, robotically assisted Heller myotomy had a greater frequency of complete esophageal emptying at 5 minutes, absence of a longitudinal upward temporal trend of Eckardt scores, showing symptom improvement without a difference in reflux, and greater freedom from reintervention than with the laparoscopic approach (Figure 5).
      Figure thumbnail gr5
      Figure 5In a 10-year review of achalasia patients, superiority of robotically assisted Heller myotomy over laparoscopic myotomy can be shown by the higher prevalence of complete esophageal emptying, a longitudinal trend of symptom scores favoring the robotic group, and greater freedom from reintervention.

      Review and Discussion

      Laparoscopic and robotically assisted Heller myotomy provide excellent palliation of achalasia symptoms. Few studies have shown superiority of the robotic approach with regard to operative time and technical complications, but most conclude that its clinical effectiveness is equivalent to laparoscopic myotomy.
      • Ali A.B.
      • Khan N.A.
      • Nguyen D.T.
      • Chihara R.
      • Chan E.Y.
      • Graviss E.A.
      • et al.
      Robotic and per-oral endoscopic myotomy have fewer technical complications compared to laparoscopic Heller myotomy.
      • Milone M.
      • Manigrasso M.
      • Vertaldi S.
      • Velotti N.
      • Aprea G.
      • Maione F.
      • et al.
      Robotic versus laparoscopic approach to treat symptomatic achalasia: systematic review with meta-analysis.
      • Horgan S.
      • Galvani C.
      • Gorodner M.V.
      • Omelanczuck P.
      • Elli F.
      • Moser F.
      • et al.
      Robotic-assisted Heller myotomy versus laparoscopic Heller myotomy for the treatment of esophageal achalasia: multicenter study.
      • Sanchez A.
      • Rodriguez O.
      • Nakhal E.
      • Davila H.
      • Valero R.
      • Sanchez R.
      • et al.
      Robotic-assisted Heller myotomy versus laparoscopic Heller myotomy for the treatment of esophageal achalasia: a case-control study.
      • Shaligram A.
      • Unnirevi J.
      • Simorov A.
      • Kothari V.M.
      • Oleynikov D.
      How does the robot affect outcomes? A retrospective review of open, laparoscopic, and robotic Heller myotomy for achalasia.
      Huffmanm and colleagues
      • Huffmanm L.C.
      • Pandalai P.K.
      • Boulton B.J.
      • James L.
      • Starnes S.L.
      • Reed M.F.
      • et al.
      Robotic Heller myotomy: a safe operation with higher postoperative quality-of-life indices.
      have additionally postulated improved quality-of-life outcomes with the robotic platform. In our comparative analysis of a propensity-matched cohort with normal esophageal morphology, we show for the first time improved subjective and objective outcomes of robotic over laparoscopic Heller myotomy in the short and intermediate term.
      Although our study suggests better outcomes with robotic Heller myotomy, our results demonstrate excellent outcomes in patients who undergo laparoscopic surgery compared with large contemporary studies on laparoscopic Heller myotomy.
      • Costantini M.
      • Salvador R.
      • Capovilla G.
      • Vallese L.
      • Costantini A.
      • Nicoletti L.
      • et al.
      A thousand and one laparoscopic Heller myotomies for esophageal achalasia: a 25-year experience at a single tertiary center.
      • Costantino C.L.
      • Geller A.D.
      • Visenio M.R.
      • Morse C.R.
      • Rattner D.W.
      Outcomes of laparoscopic Heller myotomy for achalasia: 22-year experience.
      • Fukushima N.
      • Masuda T.
      • Yano F.
      • Omura N.
      • Tsuboi K.
      • Hoshino M.
      • et al.
      Over ten-year outcomes of laparoscopic Heller-myotomy with Dor-fundoplication with achalasia: single-center experience with annual endoscopic surveillance.
      • Doubova M.
      • Gowing S.
      • Robaidi H.
      • Gilbert S.
      • Maziak D.E.
      • Shamji F.M.
      • et al.
      Long-term symptom control after laparoscopic Heller myotomy and Dor fundoplication for achalasia.
      This is not an unexpected finding given that the underlying technical elements of the procedure are similar. As such, when differences are present, they are likely to be subtle.

      Perioperative outcomes

      Operative times were slightly faster in the robotic group. Although the exact times can be debated as being faster or slower among different surgeons, in the subset of cases in which operative times were available (after 2014), with a similar and important amount of trainee involvement, the additional time of docking and de-docking the robot was not associated with delay.
      In our study, the robotic platform was associated with no intraoperative mucosal perforations. Occurrence of mucosal perforations in numerous published studies of laparoscopic Heller myotomy range from 2.9% to 16%.
      • Ali A.B.
      • Khan N.A.
      • Nguyen D.T.
      • Chihara R.
      • Chan E.Y.
      • Graviss E.A.
      • et al.
      Robotic and per-oral endoscopic myotomy have fewer technical complications compared to laparoscopic Heller myotomy.
      ,
      • Horgan S.
      • Galvani C.
      • Gorodner M.V.
      • Omelanczuck P.
      • Elli F.
      • Moser F.
      • et al.
      Robotic-assisted Heller myotomy versus laparoscopic Heller myotomy for the treatment of esophageal achalasia: multicenter study.
      ,
      • Sanchez A.
      • Rodriguez O.
      • Nakhal E.
      • Davila H.
      • Valero R.
      • Sanchez R.
      • et al.
      Robotic-assisted Heller myotomy versus laparoscopic Heller myotomy for the treatment of esophageal achalasia: a case-control study.
      ,
      • Huffmanm L.C.
      • Pandalai P.K.
      • Boulton B.J.
      • James L.
      • Starnes S.L.
      • Reed M.F.
      • et al.
      Robotic Heller myotomy: a safe operation with higher postoperative quality-of-life indices.
      ,
      • Salvador R.
      • Spadotto L.
      • Capovilla G.
      • Voltarel G.
      • Pesenti E.
      • Longo C.
      • et al.
      Mucosal perforation during laparoscopic Heller myotomy has no influence on final treatment outcome.
      Occurrence of intraoperative mucosal perforation in our overall laparoscopic group was 1.8%.
      It is also important to note the systematic approach we used in our transition from the laparoscopic platform to robotics. At least 20 independent robotic cases had been done by each surgeon before performing robotic Heller myotomy, and we received regular feedback from our gastrointestinal radiology colleagues about the barium esophagrams. We believe that this allowed us to transition from one approach to the other without the expected increase in morbidity that might be associated with a learning curve.

      Esophageal emptying

      In our quantitative assessment of esophageal emptying with timed barium esophagrams,
      • Neyaz Z.
      • Gupta M.
      • Ghoshal U.C.
      How to perform and interpret timed barium esophagogram.
      we have shown in our matched cohort a greater frequency of complete emptying with robotic Heller myotomy compared with its laparoscopic counterpart. Complete esophageal emptying at 5 minutes is a quantifiable measure of a superlative outcome from a drainage standpoint. Complete emptying was chosen as a surrogate for esophageal emptying because the wide range of esophageal morphology precludes volume calculations based on 2-dimensional imaging. It is not implied that incomplete emptying intrinsically portends a poor outcome after index surgical invention.
      We used esophageal barium column width as our end point because it has been shown previously by our group that 8-week postmyotomy esophageal width >3 cm correlates with risk of long-term reintervention.
      • Kachala S.S.
      • Rice T.W.
      • Baker M.E.
      • Rajeswaran J.
      • Thota P.N.
      • Murthy S.C.
      • et al.
      Value of routine timed barium esophagram follow-up in achalasia after myotomy.
      Because symptoms may not correlate with objective measures of esophageal emptying, they are not perfect indicators of success of myotomy.
      • Zanoni A.
      • Rice T.W.
      • Lopez R.
      • Birgisson S.
      • Shay S.S.
      • Thota P.N.
      • et al.
      Timed barium esophagram in achalasia types.
      ,
      • Kostic S.V.
      • Rice T.W.
      • Baker M.E.
      • Decamp M.M.
      • Murthy S.C.
      • Rybicki L.A.
      • et al.
      Timed barium esophagogram: a simple physiologic assessment for achalasia.
      The greater improvement in esophageal width after robotically assisted Heller myotomy may carry important clinical value. It is also interesting that a greater proportion of patients with end-stage esophagus had complete emptying with robotic surgery. However, given the even greater heterogeneity of esophagi in patients with a sigmoid esophagus, direct comparisons are not possible.

      Symptom improvement

      Our study showed that robotic and laparoscopic approaches each resulted in substantial postmyotomy symptomatic improvement in most patients, with >99% of patients having Eckardt scores of ≤3 in the short term and >96% at 1 year. Our results are consistent with many studies that have shown an equivalence of effectiveness of both approaches at relieving symptoms.
      • Ali A.B.
      • Khan N.A.
      • Nguyen D.T.
      • Chihara R.
      • Chan E.Y.
      • Graviss E.A.
      • et al.
      Robotic and per-oral endoscopic myotomy have fewer technical complications compared to laparoscopic Heller myotomy.
      • Milone M.
      • Manigrasso M.
      • Vertaldi S.
      • Velotti N.
      • Aprea G.
      • Maione F.
      • et al.
      Robotic versus laparoscopic approach to treat symptomatic achalasia: systematic review with meta-analysis.
      • Horgan S.
      • Galvani C.
      • Gorodner M.V.
      • Omelanczuck P.
      • Elli F.
      • Moser F.
      • et al.
      Robotic-assisted Heller myotomy versus laparoscopic Heller myotomy for the treatment of esophageal achalasia: multicenter study.
      • Sanchez A.
      • Rodriguez O.
      • Nakhal E.
      • Davila H.
      • Valero R.
      • Sanchez R.
      • et al.
      Robotic-assisted Heller myotomy versus laparoscopic Heller myotomy for the treatment of esophageal achalasia: a case-control study.
      • Shaligram A.
      • Unnirevi J.
      • Simorov A.
      • Kothari V.M.
      • Oleynikov D.
      How does the robot affect outcomes? A retrospective review of open, laparoscopic, and robotic Heller myotomy for achalasia.
      But as Kostic and colleagues
      • Kostic S.V.
      • Rice T.W.
      • Baker M.E.
      • Decamp M.M.
      • Murthy S.C.
      • Rybicki L.A.
      • et al.
      Timed barium esophagogram: a simple physiologic assessment for achalasia.
      postulated, it is difficult to determine the success of therapy according to symptom evaluation alone because of the exaggeration of symptom improvement and altered perception of swallowing.
      • Paterson W.G.
      Esophageal and lower esophageal sphincter response to balloon distention in patients with achalasia.
      Although resolution of symptoms remains the primary goal of achalasia therapy, it is important to also objectively assess patients’ esophageal emptying in order to define successful treatment. Nevertheless, despite little difference according to approach in the early phase, there was a more substantial difference in the later phase of the longitudinal temporal trend in Eckardt scores.
      The interplay between objective and subjective findings in patients treated for achalasia is often debated. It is our perspective that the objective of intervention in these patients is to palliate symptoms, but the goal of Heller myotomy is to improve esophageal emptying. Most patients have improvement in symptoms with improvement in esophageal emptying. The reason we make this distinction is that there is a discordance between symptom relief and esophageal emptying. Although we might debate the semantics, ultimately we do strive to improve patients’ quality of life.

      Reintervention

      As noted in our previous report,
      • Kachala S.S.
      • Rice T.W.
      • Baker M.E.
      • Rajeswaran J.
      • Thota P.N.
      • Murthy S.C.
      • et al.
      Value of routine timed barium esophagram follow-up in achalasia after myotomy.
      workup for reintervention (not reintervention) was considered when a patient had worsening symptoms or worsening timed barium esophagrams. The timed barium esophagram was considered to be worsening if its width increased by more than 1 cm and height by more than 5 cm at 5 minutes, or if there was progressive worsening to a lesser degree in serial timed barium esophagrams at 5 minutes. Reintervention was initiated only if there was objective evidence of esophagogastric junction obstruction demonstrated by esophagogastroduodenoscopy or by elevated integrated relaxation pressure on high-resolution manometry.
      Although to date only 4 patients in our robotic cohort underwent a reintervention in the form of surgery or pneumatic dilatation, in contrast to 59 laparoscopic patients, it is important to note that the extensive application of robotics in achalasia at our center was more recent, and longer-term follow-up assessment is lacking for these patients. We previously demonstrated with longer follow-up that a significant number of patients required reintervention after laparoscopic surgery, although freedom from surgical reintervention was markedly higher than for endoscopic reinterventions.
      • Raja S.
      • Schraufnagel D.P.
      • Blackstone E.H.
      • Murthy S.C.
      • Thota P.N.
      • Thuita L.
      • et al.
      Reintervention after Heller myotomy for achalasia: is it inevitable?.
      It is also important to note that in our matched cohort, when analyzed actuarially, robotically assisted Heller myotomy was associated with fewer reinterventions than laparoscopic Heller myotomy in the first few years.

      The Robotic Approach to Heller Myotomy

      Robotic platforms are purported to bring a number of advantages, including a 3-dimensional view, image magnification, and improved dexterity.
      • Ali A.B.
      • Khan N.A.
      • Nguyen D.T.
      • Chihara R.
      • Chan E.Y.
      • Graviss E.A.
      • et al.
      Robotic and per-oral endoscopic myotomy have fewer technical complications compared to laparoscopic Heller myotomy.
      ,
      • Bann S.
      • Khan M.
      • Hernandez J.
      • Munz Y.
      • Moorthy K.
      • Datta V.
      • et al.
      Robotics in surgery.
      Kim and colleagues
      • Kim S.S.
      • Guillen-Rodriguez J.
      • Little A.G.
      Optimal surgical intervention for achalasia: laparoscopic or robotic approach.
      have shown that the robotic procedure may improve outcomes by providing a more complete myotomy. However, we believe that a few tangible benefits of the robotic platform might explain the findings in our study. First, the improved optics permit enhanced visualization to perform a better and safer myotomy because of improved identification of remaining muscle fibers as well as differentiation of muscle fibers from crossing blood vessels. Improved dexterity of the instrumentation allows for precise adhesiolysis of the esophageal submucosa when needed. It is the general opinion of our group that the relatively improved adhesiolysis might be the reason for a more patulous lower esophageal sphincter after POEM compared with either robotic or laparoscopic Heller myotomy. Last, articulation of the instruments facilitates an easier mediastinal dissection, which may have been slightly longer or more complete.

      Limitation

      Our study has several limitations. First, it is an observational study of cases in a single large institution collected from a comprehensive achalasia registry. Second, although a tremendous amount of effort has been made to ensure follow-up, it has not always been feasible, in part because most patients experience significant relief of symptoms after surgery and forgo clinical follow-up for the disease. However, when those who had been lost to follow-up were contacted to reestablish care, the overwhelming majority cited lack of symptoms as the reason. Nevertheless, it is possible that some patients who remain lost to follow-up might have had reinterventions elsewhere without our knowledge. Third, although beyond the scope of this study, introduction of POEM into the therapeutic regimen of achalasia might have resulted in an intrinsic bias in selecting patients for the robotically assisted platform, where frailer patients, patients with numerous endoscopic interventions, and those with worse esophageal morphology might have been selected for alternative therapy such as POEM. Finally, given our inability to quantify the degree of sigmoidal change, direct comparison of late-stage esophageal morphology between the robotic and laparoscopic groups is challenging. Nevertheless, use of robotic surgery in achalasia shows important promise for the future of minimally invasive surgery.

      Conclusions

      Intermediate-term symptom palliation in patients who undergo Heller myotomy is excellent regardless of approach. However, assessment in a matched cohort suggests improved esophageal emptying, improved symptom palliation, and decreased risk of reintervention in patients who undergo robotically assisted Heller myotomy compared with laparoscopic myotomy. Although randomized controlled trials and prospective studies might be beneficial in determining the best surgical approach for achalasia, the ubiquity of robotic technology and paucity of surgeons using both approaches simultaneously may limit such an undertaking. Long-term follow-up is needed to see if these intermediate-term differences are sustained.

      Conflict of Interest Statement

      The authors reported no conflicts of interest.
      The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.
      Other Cleveland Clinic Esophageal Research Group Collaborators: Daniel P. Raymond, MD,a Prashanthi Thota, MD,b Scott L. Gabbard, MD,b Mark E. Baker, MD,c and Jesse M. P. Rappaport, MDa
      Departments of aThoracic and Cardiovascular Surgery, bGastroenterology and Hepatology, and cDiagnostic Radiology, Cleveland Clinic, Cleveland, Ohio

      Supplementary Data

      • Video 1

        We describe our technique for a robotically assisted Heller myotomy with a modified Dor fundoplication and provide our rationale for certain steps and pearls for the procedure. Video available at: https://www.jtcvs.org/article/S0022-5223(22)00600-6/fulltext.

      Appendix E1. Variables available for multivariable analyses

      Demographics

      Sex
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      , age (years),
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      weight (kg), height (m), body mass index (kg/m2),
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      body surface area (m2), race.
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.

      Preoperative Data

      American Society of Anesthesiologists class,
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      achalasia type (type I,
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      type II
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      ), prior botulinum toxin injections.
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.

      Timed Barium Esophagram Variables

      Barium column width (cm) at 1
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      and 5
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      minutes, preoperative barium volume ≥250 mL.
      Included in propensity model for robotic versus laparoscopic Heller myotomy among patients with normal esophageal morphology.
      Figure thumbnail fx5
      Figure E1Number of patients and timed barium esophagram (TBE) records across time for robotically assisted and laparoscopic Heller myotomy in propensity-matched patients with normal esophageal morphology. This figure is a companion to text .
      Figure thumbnail fx9
      Figure E2Number of patients and patient-reported Eckardt scores across time for robotically assisted and laparoscopic Heller myotomy in propensity-matched patients with normal esophageal morphology. This figure is a companion to text .
      Figure thumbnail fx6
      Figure E3Quality of propensity matching of patients with normal esophageal morphology who underwent robotically assisted or laparoscopic Heller myotomy. A, Mirrored histogram of distribution of propensity scores for both groups before and after matching. Blue and red areas represent the propensity-matched cohort. This figure depicts the distributions of the propensity scores and the spectrum of coverage of the matched cohorts. B, Standardized differences of selected variables before and after matching. Vertical dashed lines at −10% and +10% indicate boundaries of desirable matching. Yellow triangles represent standardized differences before propensity matching, with positive values indicating variables more common in the robotic group and negative values indicating variables more common in the laparoscopic group. Green squares represent characteristics after matching. ASA, American Society of Anesthesiologists; BMI, body mass index; IRP, integrated relaxation pressure; Preop, preoperative.
      Figure thumbnail fx7
      Figure E4Patients with complete emptying on timed barium esophagram at 5 minutes in the short term (<6 months) in the overall cohort, stratified by esophageal morphology in patients who underwent robotically assisted (blue) or laparoscopic (red) Heller myotomy in the short term (<6 months) postoperatively.
      Figure thumbnail fx8
      Figure E5First reintervention after robotically assisted (blue) and laparoscopic (red) Heller myotomy. Each symbol is a reintervention, and vertical bars are asymmetric 68% confidence intervals equivalent to ±1 standard error. Dashed line represents patients followed without an event.
      Table E1Preoperative characteristics of patients who underwent robotically assisted (robotic) and laparoscopic Heller myotomy
      CharacteristicsRobotic (N = 170)Laparoscopic (N = 277)SMD, %
      n
      Patients with data available.
      No. (%) or mean ± SDn
      Patients with data available.
      No. (%) or mean ± SD
      Demographics
       Female17078 (46)277136 (49)−6.4
       Race167270
      White147 (88)242 (90)−5.1
      Black9 (5.4)24 (8.9)−14
      Other11 (6.6)4 (1.5)26
       Age, y17050 ± 1627749 ± 166.7
       Height, m1701.7 ± 0.12651.71 ± 0.111.1
       Weight, kg17078 ± 1726778 ± 181.8
       Body surface area, m21701.95 ± 0.252651.9 ± 0.273.2
       Body mass index, kg/m217026 ± 5.026526 ± 5.42.8
      Preoperative data
       Previous interventions
      Botulinum toxin injections16613 (7.8)27036 (13)−18
      Pneumatic dilatations1672 (1.2)27026 (9.6)−38
       Achalasia type155244
      I22 (14)59 (24)−25
      II116 (76)170 (70)14
      III3 (1.9)12 (4.9)−16
      EGJ outflow obstruction8 (5.2)2 (0.82)26
      Other4 (2.6)1 (0.41)18
       ASA class16726761
      I2 (1.2)11 (4.1)
      II31 (19)97 (36)
      III91 (54)141 (53)
      IV43 (26)18 (6.7)
      Timed barium esophagram
       Width at 1 min, cm1543.5 ± 1.42643.08 ± 1.331
       Width at 5 min, cm1553.02 ± 1.62652.6 ± 1.525
       Barium volume ≥250 mL15567 (43)264156 (59)−32
       Barium volume, mL155185 ± 71264203 ± 65−27
      Manometry
       IRP, mm Hg15123 ± 1326525 ± 12−15
      Symptoms
       Eckardt score1335316
      ≤38 (6.0)3 (5.7)
      >3125 (94)50 (94)
      SMD, Standardized mean difference; EGJ, esophagogastric junction; ASA, American Society of Anesthesiologists; IRP, integrated relaxation pressure.
      Patients with data available.
      Table E2Parsimonious model of factors associated with robotically assisted versus laparoscopic Heller myotomy in 328 patients with normal esophageal morphology
      FactorsEstimate ± SEP valueReliability (%)
      Percent of times factor appeared in 1000 bootstrap models.
      Preoperative ASA class0.91 ± 0.19<.0001100
      Preoperative barium volume ≥250 mL−0.61 ± 0.25.0178
      Type I achalasia−0.79 ± 0.34.0260
      Preoperative barium column width at 1 min, cm0.42 ± 0.12.000487
      C-statistic = 0.72.
      ASA, American Society of Anesthesiologists.
      Percent of times factor appeared in 1000 bootstrap models.
      Table E3Perioperative and postoperative outcomes
      OutcomesRobotic (N = 170)Laparoscopic (N = 277)
      n
      Patients with data available.
      No. (%) or median [p15, p85]n
      Patients with data available.
      No. (%) or median [p15, p85]
      Perioperative
       Procedure time, min167121 [100, 150]101142 [115, 171]
       Length of stay, d1701 [1, 2]2771 [1, 2]
       Complications170277
      Mucosal perforation0 (0)5 (1.8)
      Delayed leak0 (0)1 (0.4)
      Postoperative hematoma0 (0)1 (0.4)
      Short-term (<6 mo)
       Esophageal emptying (5 min)
      Complete emptying13277 (58)241115 (48)
      Normal9663 (66)17999 (55)
      End-stage3614 (39)6216 (26)
      Worsening1221 (0.82)23218 (7.8)
      Normal961 (1.0)1798 (4.5)
      End-stage260 (0)5310 (19)
       Symptoms/Eckardt score14366
      ≤3143 (100)65 (98)
      >30 (0)1 (2.0)
       Reflux/DeMeester score80144
      Normal68 (85)122 (85)
      Abnormal12 (15)22 (15)
      Postoperative
       Reinterventions
      Reinterventions during follow-up of patients in the study period.
      459
      Pneumatic dilatation339
      Heller myotomy03
      Esophagectomy04
      POEM113
      p15, p85, 15th, 85th percentiles; POEM, per-oral endoscopic myotomy.
      Patients with data available.
      Reinterventions during follow-up of patients in the study period.

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