Advertisement

Late recovery of atrioventricular conduction after postsurgical chronic atrioventricular block is not exceptional

Open ArchivePublished:June 13, 2012DOI:https://doi.org/10.1016/j.jtcvs.2012.05.012

      Objective

      Postsurgical atrioventricular block may complicate surgery for congenital heart defects and is generally considered permanent when persisting longer than 14 days after surgery. In this study, we evaluate the occurrence of spontaneous late recovery of atrioventricular conduction in postsurgical chronic atrioventricular block and discuss its clinical implications.

      Methods

      We retrospectively reviewed all cardiac surgical procedures on cardiopulmonary bypass between January 1993 and November 2010 in subjects younger than 18 years. Patients with postsurgical advanced second- or third-degree atrioventricular block persisting longer than 14 days after surgery were included.

      Results

      Of a total of 2850 cardiac surgical procedures on cardiopulmonary bypass, 59 (2.1%) were immediately complicated by chronic postsurgical atrioventricular block of advanced second (n = 4) or third degree (n = 55). In another 6 patients (0.2%), late occurrence of chronic advanced second- (n = 3) or third-degree (n = 3) atrioventricular block, without signs of any etiology other than previous surgery, was seen 0.4 to 10 years after surgery (median, 5.7 years). Late (>2 weeks) regression to either completely normal atrioventricular conduction or asymptomatic first-degree atrioventricular block occurred 3 weeks to 7 years (median, 3.1 years) after surgery in 7 (12%) patients with immediate postsurgical chronic atrioventricular block.

      Conclusions

      Complete recovery of atrioventricular conduction or regression to asymptomatic first-degree atrioventricular block occurred in 12% of patients with postsurgical chronic second- or third-degree atrioventricular block. To prevent unnecessary adverse side effects of chronic ventricular pacing and to prolong battery longevity, ventricular pacing should be minimized in patients with recovered normal atrioventricular conduction.

      CTSNet classification

      Abbreviation and Acronym:

      AV (atrioventricular)
      Postsurgical complete atrioventricular (AV) block complicates approximately 3% of all surgical procedures for congenital heart defects involving cardiopulmonary bypass.
      • Weindling S.N.
      • Saul J.P.
      • Gamble W.J.
      • Mayer J.E.
      • Wessel D.
      • Walsh E.P.
      Duration of complete atrioventricular block after congenital heart disease surgery.
      Postsurgical AV block persisting after 7 to 14 days is usually considered to be permanent and is a class I indication for implantation of a permanent pacemaker.
      • Epstein A.E.
      • DiMarco J.P.
      • Ellenbogen K.A.
      • Estes 3rd, N.A.
      • Freedman R.A.
      • Gettes L.S.
      • et al.
      ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons.
      Although some retrospective studies have reported late recovery of AV conduction in patients who were considered to have permanent postsurgical AV block,
      • Batra A.S.
      • Wells W.J.
      • Hinoki K.W.
      • Stanton R.A.
      • Silka M.J.
      Late recovery of atrioventricular conduction after pacemaker implantation for complete heart block associated with surgery for congenital heart disease.
      • Reid J.M.
      • Coleman E.N.
      • Doig W.
      Reversion to sinus rhythm 11 years after surgically induced heart block.
      such recovery is generally thought to be exceptional. It is of clinical importance to identify patients in whom permanent pacing could be avoided, however, because permanent conventional ventricular pacing for complete AV block is associated with decreased left ventricular function and an increased risk of heart failure.
      • van Geldorp I.E.
      • Vanagt W.Y.
      • Prinzen F.W.
      • Delhaas T.
      Chronic ventricular pacing in children: toward prevention of pacing-induced heart disease.
      The main objective of this study was therefore to determine the incidence of recovery of AV conduction after postsurgical chronic AV block and to discuss its clinical implications.

      Materials and Methods

      Study Population

      All patients with AV block after surgery for congenital heart disease undergone at an age younger than 18 years between January 1, 1993, and November 1, 2010, were retrospectively selected from the database of the department of Pediatric Cardiology of University Hospitals Leuven (Leuven, Belgium). Charts of all patients with either AV block or a pacemaker implanted after surgery were reviewed. Patients with advanced second-degree or complete AV block persisting longer than 14 days after cardiac surgery were included, whereas patients with congenital or preexisting AV block were excluded. From the included patients, the following data were obtained: date of birth, cardiac diagnosis, type and date of surgery after which AV block occurred, and degree of AV block. Follow-up data on patients status were obtained from the (at least) biannual routine visit to University Hospitals Leuven or the referring centers.

      Outcome Measures

      Advanced second-degree and complete postsurgical AV blocks that persisted longer than 14 postoperative days were considered to represent postsurgical chronic AV block. Late occurrence of postsurgical AV block was characterized by the occurrence of second-degree or complete chronic AV block after the immediate (14 days) postsurgical period in the absence of familial or infectious etiology. Regression from postsurgical chronic AV block either to completely normal AV conduction (PQ time <0.2 seconds) or to asymptomatic first-degree AV block was considered to represent late recovery of AV conduction.

      Results

      Incidence of Postsurgical Chronic Advanced Second- or Third-Degree AV Block

      Between January 1, 1993, and November 1, 2010, a total of 2850 cardiac surgical procedures with cardiopulmonary bypass were performed in children. From the database, 59 cases (2.1%) were identified in which surgery was immediately complicated by postsurgical chronic AV block of advanced second (n = 4) or third degree (n = 55). Three of these patients died within the postoperative period before discharge but later than 14 days after surgery. These patients were considered to have postsurgical chronic AV block without recovery.
      Late occurrence of chronic advanced second-degree (n = 3) or third-degree (n = 3) AV block, without signs pointing to any etiology other than previous surgery, was found in 6 additional patients (0.2%) at 0.4 to 10 years after surgery (median, 5.7 years). Only 1 of these patients with late occurrence of chronic AV block also had transient complete AV block in the immediate postsurgical period after closure of a ventricular septal defect.
      Summing up, the overall incidence of immediate and late postsurgical chronic AV block of advanced degree was 65 of 2850 (2.3%). The results are schematically represented in Figure 1.
      Figure thumbnail gr1
      Figure 1Schematic overview of results. Chronic atrioventricular (AV) block was considered to be atrioventricular block of advanced second or third degree persisting longer than 14 days.
      Among the patients with immediate and late postsurgical chronic AV block, surgery was performed at an age of 0 to 16 years (median, 0.9 years). The various types of surgical interventions resulting in AV block are presented in Table 1. For each surgical procedure, a risk-percentage is indicated; however, some of these risk-percentages are based on relatively small numbers of patients and have undoubtedly been influenced by chance.
      Table 1Postsurgical chronic atrioventricular block by type of surgery
      Type of surgeryTotal (n)Chronic AV block (n)Risk (%)
      VSD procedures1194312.6
       VSD closure111.7
       VSD closure in complex congenital heart disease18
      Complex congenital heart disease included tetralogy of Fallot (n = 2 with postsurgical chronic AV block), transposition of the great arteries (n = 9 with postsurgical chronic AV block), double-outlet right ventricle (n = 3 with postsurgical chronic AV block), VSD and left ventricular outflow tract obstruction (n = 3 with postsurgical chronic AV block), and truncus arteriosus (n = 1 with postsurgical chronic AV block).
      3.2
       VSD enlargement2
      AV septal defect correction244145.7
      Tricuspid valve procedures33412.1
      Mitral valve procedures613
      Two patients had surgery for the left ventricular outflow tract within the same surgical procedure.
      4.9
      Left ventricular outflow tract procedures11110
      One patient had tricuspid valve surgery within the same surgical procedure.
      9.0
      Atrial septal defect closure (surgical)37710.3
      Other83020.2
      AV, Atrioventricular block; VSD, ventricular septal defect.
      Complex congenital heart disease included tetralogy of Fallot (n = 2 with postsurgical chronic AV block), transposition of the great arteries (n = 9 with postsurgical chronic AV block), double-outlet right ventricle (n = 3 with postsurgical chronic AV block), VSD and left ventricular outflow tract obstruction (n = 3 with postsurgical chronic AV block), and truncus arteriosus (n = 1 with postsurgical chronic AV block).
      Two patients had surgery for the left ventricular outflow tract within the same surgical procedure.
      One patient had tricuspid valve surgery within the same surgical procedure.

      Late Recovery of AV Conduction After Postsurgical Chronic AV Block

      Late improvement in AV conduction was observed in 12% of the patients with immediate postsurgical chronic AV block (Figure 1 and Table 2). Four patients (6.8%) showed completely normal AV conduction at 23 days, 11 weeks, 6.8 years, and 7.0 years after immediate postsurgical complete chronic AV block. Regression of postsurgical chronic AV block of advanced degree to asymptomatic first-degree AV block was observed in 3 additional patients (5.1%) at 22 days, 3.1 years, and 6.2 years after surgery. In 2 of the latter patients, even completely normal AV conduction was observed during further follow-up (after 22 days + 4.6 years and 6.2 + 1.1 years, respectively). Regression toward normal AV conduction was not observed in the 6 patients with late occurrence of AV block.
      Table 2Characteristics of patients with recovery of atrioventricular conduction after postsurgical chronic atrioventricular block
      CaseHeart diseaseProcedure and timing (age [y] and year of surgery)Chronic postsurgical AV blockTime to recovery of conductionFollow-up
      Duration of follow-up after recovery is given in parentheses.
      1AVSDAVSD correction (4.0 y; 2006)Complete22 d; 4.7 yAsymptomatic first-degree AV block; completely normal AV conduction 4.6 y later (5.1 y)
      2d-TGA, VSD, PSVSD closure (2.6 y; 2007)Complete23 dNormal AV conduction until death (Klebsiella sepsis) (2 mo)
      3Isolated VSDVSD closure (5.9 y; 2003)Complete11 wkNormal AV conduction during 3.5 y; subsequent relapse into complete AV block (7 y)
      4AVSDAVSD correction (6.2 y; 1996)Second degree (advanced)3.1 yAsymptomatic first-degree AV block (3.5 y)
      5AVSDAVSD correction (0.6 y; 2003)Second degree (advanced)6.2 y; 7.3 yAsymptomatic first-degree AV block; completely normal AV conduction 1.1 y later (7.8 y)
      6AS (bicuspid)LVOT (Ross) procedure (4.5 y; 2004)Complete6.8 yNormal AV conduction (11 mo)
      7AVSDAVSD correction (0.3 y; 2000)Complete7.0 yNormal AV conduction (3.9 y)
      AS, Aortic valve stenosis; ASD, atrial septal defect; AV, atrioventricular; AVSD, atrioventricular septal defect; d-TGA, dextrotransposition of the great arteries; LVOT, left ventricular outflow tract; PS, pulmonary stenosis; VSD, ventricular septal defect.
      Duration of follow-up after recovery is given in parentheses.

      Follow-up of Patients With Recovered AV Conduction

      Follow-up after recovery of AV conduction varied between 2 months and 7 years (median follow-up was 3.5 years). During follow-up, 1 patient died of Klebsiella sepsis 2 months after recovery of completely normal AV conduction, and 1 patient had a relapse into complete AV block 3.5 years after recovery of completely normal AV conduction. When recovery of AV conduction was recognized, pacemakers were left in situ, and battery longevity was prolonged by adjustment of the pacemaker settings to a backup mode.

      Discussion

      Postsurgical AV block is usually considered to be permanent if it persists after 7 to 14 days.
      • Epstein A.E.
      • DiMarco J.P.
      • Ellenbogen K.A.
      • Estes 3rd, N.A.
      • Freedman R.A.
      • Gettes L.S.
      • et al.
      ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons.
      In 12% of our study population of 59 patients with immediate postsurgical chronic second- or third-degree AV block, however, either complete recovery of AV conduction or regression to asymptomatic first-degree AV block occurred between 3 weeks and 7 years after surgery.

      Recovery of AV Conduction After Postsurgical AV Block

      It is well known that postsurgical AV block may resolve spontaneously within the first days after surgery. About 50% of postsurgical complete AV blocks will resolve within the first week, and about 63% within 30 days after surgery.
      • Weindling S.N.
      • Saul J.P.
      • Gamble W.J.
      • Mayer J.E.
      • Wessel D.
      • Walsh E.P.
      Duration of complete atrioventricular block after congenital heart disease surgery.
      The possibility of postsurgical AV block resolving years after surgery, however, is less well recognized.
      The first description of very late recovery of AV conduction after complete postsurgical AV block was given in 1976 by Reid and associates,
      • Reid J.M.
      • Coleman E.N.
      • Doig W.
      Reversion to sinus rhythm 11 years after surgically induced heart block.
      who described a patient with spontaneous reversion to (persisting) normal AV conduction after an interval of 11 years. In the subsequent era of 1976 through 1996, Bruckheimer and colleagues
      • Bruckheimer E.
      • Berul C.I.
      • Kopf G.S.
      • Hill S.L.
      • Warner K.A.
      • Kleinman C.S.
      • et al.
      Late recovery of surgically-induced atrioventricular block in patients with congenital heart disease.
      found recovered AV conduction in 32% of 44 patients receiving pacemakers for postsurgical AV block, with a median follow-up until recognition of recovery of 5.5 years (range, 0.1-20 years). The incidence of recovered AV conduction was 21% when only patients with pacemaker implantation later than 14 days after surgery were considered. More recently, Batra and coworkers
      • Batra A.S.
      • Wells W.J.
      • Hinoki K.W.
      • Stanton R.A.
      • Silka M.J.
      Late recovery of atrioventricular conduction after pacemaker implantation for complete heart block associated with surgery for congenital heart disease.
      reported recovery of AV conduction within the first 6 months after surgery in 9.6% of 72 patients with a complete AV block persisting beyond 14 days after surgery.
      • Batra A.S.
      • Wells W.J.
      • Hinoki K.W.
      • Stanton R.A.
      • Silka M.J.
      Late recovery of atrioventricular conduction after pacemaker implantation for complete heart block associated with surgery for congenital heart disease.
      The differences between these studies and our own may be explained by the small number of patients in each study, which increases the influence of chance. Moreover, the eras of investigation, the diverse retrospective search strategies and structures of databases, and the slightly varying inclusion criteria are also factors. It might be disputed whether the patient in our series with recovered conduction and relapse into advanced AV block 3.5 years later truly ought to be included with the other 6 patients with recovered AV conduction. If that patient were not counted as a patient with recovered AV conduction, the 11.9% recovery rate would drop to 10.2%.

      Onset of Postsurgical AV Block After the Immediate Postsurgical Period

      We identified 6 patients of 2850 (0.2%) with late onset of chronic postsurgical AV block, which occurred as late as 10 years after surgery (median, 5.7 years; range, 0.4-10 years). The true incidence of late onset of AV block following surgery, however, is difficult to determine because its discovery at least requires careful follow-up for a lifetime. Furthermore, when conduction disturbances are recognized many years after surgery, it may be unclear whether they are directly related to the surgical intervention. It has been suggested that late onset of AV block is associated with transient AV block in the immediate postsurgical period and with persisting conduction disorders such as left or right bundle branch block
      • Krongrad E.
      Prognosis for patients with congenital heart disease and postoperative intraventricular conduction defects.
      • Lin A.
      • Mahle W.T.
      • Frias P.A.
      • Fischbach P.S.
      • Kogon B.E.
      • Kanter K.R.
      • et al.
      Early and delayed atrioventricular conduction block after routine surgery for congenital heart disease.
      ; however, late onset of AV block has also been observed in patients without any history of conduction disorders.
      • Liberman L.
      • Pass R.H.
      • Hordof A.J.
      • Spotnitz H.M.
      Late onset of heart block after open heart surgery for congenital heart disease.
      In our study, only one of the six patients with late onset of AV block had transient third-degree AV block in the immediate postoperative period.

      Avoiding Unnecessary Ventricular Pacing in Patients With Postsurgical Chronic AV Block

      Pacemaker implantation improves the outcome of (postsurgical) advanced second- or third-degree AV block. When pacing became available, a significant reduction in mortality from postsurgical AV block was reported.
      • Lillehei C.W.
      • Sellers R.D.
      • Bonnabeau R.C.
      • Eliot R.S.
      Chronic postsurgical complete heart block. With particular reference to prognosis, management, and a new P-wave pacemaker.
      In addition to the obvious beneficial effects of the restoration of heart rate, the unpredictable risk of sudden cardiac death and left ventricular failure associated with untreated complete heart block are treated by chronic ventricular pacing.
      • Udink ten Cate F.E.
      • Breur J.M.
      • van Woerkom J.M.
      • Kruize A.A.
      • Stoutenbeek P.
      • Meijboom E.J.
      [Congenital complete atrioventricular block in children: pathogenesis and clinical outcomes].
      • Michaelsson M.
      • Riesenfeld T.
      • Jonzon A.
      Natural history of congenital complete atrioventricular block.
      Weindling and colleagues
      • Weindling S.N.
      • Saul J.P.
      • Gamble W.J.
      • Mayer J.E.
      • Wessel D.
      • Walsh E.P.
      Duration of complete atrioventricular block after congenital heart disease surgery.
      concluded that there is minimal benefit in delaying pacemaker implantation beyond 9 days after surgery, because 97% of the patients who show recovery of AV conduction do so within the first 9 postoperative days. Postsurgical AV block persisting longer than 7 to 14 days is therefore usually considered to be permanent and is a class I indication for implantation of a permanent pacemaker.
      • Epstein A.E.
      • DiMarco J.P.
      • Ellenbogen K.A.
      • Estes 3rd, N.A.
      • Freedman R.A.
      • Gettes L.S.
      • et al.
      ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons.
      Without exception, however, ventricular pacing induces an abnormal electrical activation pattern, which may cause adverse mechanical dyssynchrony. Conventional ventricular pacing is associated with impairment of pump function, left ventricular remodeling, and increased risk of heart failure.
      • Tantengco M.V.
      • Thomas R.L.
      • Karpawich P.P.
      Left ventricular dysfunction after long-term right ventricular apical pacing in the young.
      • Karpawich P.P.
      Chronic right ventricular pacing and cardiac performance: the pediatric perspective.
      • Thambo J.B.
      • Bordachar P.
      • Garrigue S.
      • Lafitte S.
      • Sanders P.
      • Reuter S.
      • et al.
      Detrimental ventricular remodeling in patients with congenital complete heart block and chronic right ventricular apical pacing.
      • van Geldorp I.E.
      • Delhaas T.
      • Gebauer R.A.
      • Frias P.
      • Tomaske M.
      • Friedberg M.K.
      • et al.
      Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey.
      Because normal intrinsic activation patterns are superior to the activation patterns induced by conventional pacing, ventricular pacing should be avoided (or minimized) in patients with (partially) preserved AV conduction and an intact His-Purkinje system.
      • van Geldorp I.E.
      • Vanagt W.Y.
      • Prinzen F.W.
      • Delhaas T.
      Chronic ventricular pacing in children: toward prevention of pacing-induced heart disease.
      • Janousek J.
      • Tomek V.
      • Chaloupecky V.
      • Gebauer R.A.
      Dilated cardiomyopathy associated with dual-chamber pacing in infants: improvement through either left ventricular cardiac resynchronization or programming the pacemaker off allowing intrinsic normal conduction.

      Clinical Implications

      Chronic AV block of advanced degree is an important complication of surgery for congenital heart disease. To inform patients and parents adequately about this complication and its prognosis, surgeons and cardiologists should be aware of the possibility of postsurgical AV block regression, even many years after surgery. Moreover, to prevent unnecessary adverse side effetcs of chronic ventricular pacing, we think that it is of clinical importance to identify patients in whom permanent pacing may be avoidable. Raised awareness of the existence of recovery of AV conduction after chronic postsurgical AV block will therefore also be important for physicians who follow up patients with postsurgical AV block and a pacemaker. In the patient with recovered AV conduction, the ventricular pacemaker should be reprogrammed as a back-up device to avoid adverse effects of unnecessary ventricular pacing and to prolong battery longevity. Because of the potential risk of recurrence of AV block in patients with a history of postsurgical AV block (1 of our patients with recovered normal AV conduction had a relapse into complete AV block 3.5 years later) and because of the clinical importance of a recurrent AV block, it may be best practice to keep the device in situ and to replace the generator if the battery is depleted. It is recommended that cardiologists providing long-term follow-up care of patients with surgery for congenital heart disease should be alert to the issue of late incidence of postsurgical AV block and respond promptly and proactively to suggestive symptoms such as syncope. Cardiologists should undertake heart rhythm monitoring at regular intervals in symptom-free patients, because an AV block that may unexpectedly present many years after surgery is potentially life threatening.
      • Lin A.
      • Mahle W.T.
      • Frias P.A.
      • Fischbach P.S.
      • Kogon B.E.
      • Kanter K.R.
      • et al.
      Early and delayed atrioventricular conduction block after routine surgery for congenital heart disease.
      • Liberman L.
      • Pass R.H.
      • Hordof A.J.
      • Spotnitz H.M.
      Late onset of heart block after open heart surgery for congenital heart disease.
      • Goldman B.S.
      • Williams W.G.
      • Hill T.
      • Hesslein P.S.
      • McLaughlin P.R.
      • Trusler G.A.
      • et al.
      Permanent cardiac pacing after open heart surgery: congenital heart disease.
      • Gross G.J.
      • Chiu C.C.
      • Hamilton R.M.
      • Kirsh J.A.
      • Stephenson E.A.
      Natural history of postoperative heart block in congenital heart disease: implications for pacing intervention.

      Study Limitations

      The retrospective nature of the study is a limitation. In addition, intermittent follow-up means that the exact date of recovery of AV conduction could not precisely be assessed. As in other studies on this subject, the population of our study was too small and too heterogeneous to identify positive prognostic factors for recovery of AV block, such as the underlying defect, surgical techniques, or immediate postoperative period. To permit analysis of predictors for either the occurrence of immediate or late postsurgical AV block or the occurrence of recovery of AV conduction after postsurgical chronic AV block, further research should be performed in larger (multicenter) study populations. Because of the low incidence of chronic postsurgical AV block, prospective studies with large patient numbers are hard to perform.

      Conclusions

      In our study population of 59 patients with immediate chronic postsurgical second- or third-degree AV block, either complete recovery of AV conduction or regression to asymptomatic first-degree AV block occurred between 3 weeks and 7 years after surgery in 12% of the patients. To prevent unnecessary adverse side effects of chronic ventricular pacing and to prolong battery longevity, it is important to minimize ventricular pacing by reprogramming the pacemaker as a backup device in patients with recovered normal AV conduction.

      References

        • Weindling S.N.
        • Saul J.P.
        • Gamble W.J.
        • Mayer J.E.
        • Wessel D.
        • Walsh E.P.
        Duration of complete atrioventricular block after congenital heart disease surgery.
        Am J Cardiol. 1998; 82: 525-527
        • Epstein A.E.
        • DiMarco J.P.
        • Ellenbogen K.A.
        • Estes 3rd, N.A.
        • Freedman R.A.
        • Gettes L.S.
        • et al.
        ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons.
        J Am Coll Cardiol. 2008; 51 (Erratum in: J Am Coll Cardiol. 2009;53:1473. Erratum in: J Am Coll Cardiol. 2009;53:147): e1-62
        • Batra A.S.
        • Wells W.J.
        • Hinoki K.W.
        • Stanton R.A.
        • Silka M.J.
        Late recovery of atrioventricular conduction after pacemaker implantation for complete heart block associated with surgery for congenital heart disease.
        J Thorac Cardiovasc Surg. 2003; 125: 1291-1293
        • Reid J.M.
        • Coleman E.N.
        • Doig W.
        Reversion to sinus rhythm 11 years after surgically induced heart block.
        Br Heart J. 1976; 38: 1217-1219
        • van Geldorp I.E.
        • Vanagt W.Y.
        • Prinzen F.W.
        • Delhaas T.
        Chronic ventricular pacing in children: toward prevention of pacing-induced heart disease.
        Heart Fail Rev. 2011; 16: 305-314
        • Bruckheimer E.
        • Berul C.I.
        • Kopf G.S.
        • Hill S.L.
        • Warner K.A.
        • Kleinman C.S.
        • et al.
        Late recovery of surgically-induced atrioventricular block in patients with congenital heart disease.
        J Interv Card Electrophysiol. 2002; 6: 191-195
        • Krongrad E.
        Prognosis for patients with congenital heart disease and postoperative intraventricular conduction defects.
        Circulation. 1978; 57: 867-870
        • Lin A.
        • Mahle W.T.
        • Frias P.A.
        • Fischbach P.S.
        • Kogon B.E.
        • Kanter K.R.
        • et al.
        Early and delayed atrioventricular conduction block after routine surgery for congenital heart disease.
        J Thorac Cardiovasc Surg. 2010; 140: 158-160
        • Liberman L.
        • Pass R.H.
        • Hordof A.J.
        • Spotnitz H.M.
        Late onset of heart block after open heart surgery for congenital heart disease.
        Pediatr Cardiol. 2008; 29: 56-59
        • Lillehei C.W.
        • Sellers R.D.
        • Bonnabeau R.C.
        • Eliot R.S.
        Chronic postsurgical complete heart block. With particular reference to prognosis, management, and a new P-wave pacemaker.
        J Thorac Cardiovasc Surg. 1963; 46: 436-456
        • Udink ten Cate F.E.
        • Breur J.M.
        • van Woerkom J.M.
        • Kruize A.A.
        • Stoutenbeek P.
        • Meijboom E.J.
        [Congenital complete atrioventricular block in children: pathogenesis and clinical outcomes].
        Ned Tijdschr Geneeskd. 2002; 146 (Dutch): 1777-1781
        • Michaelsson M.
        • Riesenfeld T.
        • Jonzon A.
        Natural history of congenital complete atrioventricular block.
        Pacing Clin Electrophysiol. 1997; 20: 2098-2101
        • Tantengco M.V.
        • Thomas R.L.
        • Karpawich P.P.
        Left ventricular dysfunction after long-term right ventricular apical pacing in the young.
        J Am Coll Cardiol. 2001; 37: 2093-2100
        • Karpawich P.P.
        Chronic right ventricular pacing and cardiac performance: the pediatric perspective.
        Pacing Clin Electrophysiol. 2004; 27: 844-849
        • Thambo J.B.
        • Bordachar P.
        • Garrigue S.
        • Lafitte S.
        • Sanders P.
        • Reuter S.
        • et al.
        Detrimental ventricular remodeling in patients with congenital complete heart block and chronic right ventricular apical pacing.
        Circulation. 2004; 110: 3766-3772
        • van Geldorp I.E.
        • Delhaas T.
        • Gebauer R.A.
        • Frias P.
        • Tomaske M.
        • Friedberg M.K.
        • et al.
        Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey.
        Heart. 2011; 97: 2051-2055
        • Janousek J.
        • Tomek V.
        • Chaloupecky V.
        • Gebauer R.A.
        Dilated cardiomyopathy associated with dual-chamber pacing in infants: improvement through either left ventricular cardiac resynchronization or programming the pacemaker off allowing intrinsic normal conduction.
        J Cardiovasc Electrophysiol. 2004; 15: 470-474
        • Goldman B.S.
        • Williams W.G.
        • Hill T.
        • Hesslein P.S.
        • McLaughlin P.R.
        • Trusler G.A.
        • et al.
        Permanent cardiac pacing after open heart surgery: congenital heart disease.
        Pacing Clin Electrophysiol. 1985; 8: 732-739
        • Gross G.J.
        • Chiu C.C.
        • Hamilton R.M.
        • Kirsh J.A.
        • Stephenson E.A.
        Natural history of postoperative heart block in congenital heart disease: implications for pacing intervention.
        Heart Rhythm. 2006; 3: 601-604