Fate of long-term survivors of Mustard procedure (inflow repair) for simple and complex transposition of the great arteries

Resolution of Hypoxia and Ascites With Percutaneous Intervention of Mustard Baffle Obstruction and Leak

A 45-year-old man with history of Mustard repair for transposition of the great arteries, cirrhosis, and chronic hypoxemic respiratory failure presented for subacute worsening of his chronic symptoms, which were found to be secondary to a previously unrecognized baffle stenosis and leak. Percutaneous intervention resolved his ascites and hypoxia. (Level of Difficulty: Intermediate.)

Predictors of Late Mortality in D-Transposition of the Great Arteries After Atrial Switch Repair: Systematic Review and Meta-Analysis

Background

Existing data on predictors of late mortality and prevention of sudden cardiac death after atrial switch repair surgery for D‐transposition of the great arteries (D‐TGA) are heterogeneous and limited by statistical power.

Methods and Results

We conducted a systematic review and meta‐analysis of 29 observational studies, comprising 5035 patients, that reported mortality after atrial switch repair with a minimum follow‐up of 10 years. We also examined 4 additional studies comprising 105 patients who reported rates of implantable cardioverter‐defibrillator therapy in this population. Average survival dropped to 65% at 40 years after atrial switch repair, with sudden cardiac death accounting for 45% of all reported deaths. Mortality was significantly lower in cohorts that were more recent and operated on younger patients. Patient‐level risk factors for late mortality were history of supraventricular tachycardia (odds ratio [OR] 3.8, 95% CI 1.4–10.7), Mustard procedure compared with Senning (OR 2.9, 95% CI 1.9–4.5) and complex D‐TGA compared with simple D‐TGA (OR 4.4, 95% CI 2.2–8.8). Significant risk factors for sudden cardiac death were history of supraventricular tachycardia (OR 4.7, 95% CI 2.2–9.8), Mustard procedure (OR 2.2, 95% CI 1.1–4.1), and complex D‐TGA (OR 5.7, 95% CI 1.8–18.0). Out of a total 124 implantable cardioverter‐defibrillator discharges over 330 patient‐years in patients with implantable cardioverter‐defibrillators for primary prevention, only 8% were appropriate.

Conclusions

Patient‐level risk of both mortality and sudden cardiac death after atrial switch repair are significantly increased by history of supraventricular tachycardia, Mustard procedure, and complex D‐TGA. This knowledge may help refine current selection practices for primary prevention implantable cardioverter‐defibrillator implantation, given disproportionately high rates of inappropriate discharges.

Echocardiographic Classification and Surgical Approaches to Double-Outlet Right Ventricle for Great Arteries Arising Almost Exclusively from the Right Ventricle

Selecting an appropriate surgical approach for double-outlet right ventricle (DORV), a complex congenital cardiac malformation with many anatomic variations, is difficult. Therefore, we determined the feasibility of using an echocardiographic classification system, which describes the anatomic variations in more precise terms than the current system does, to determine whether it could help direct surgical plans. Our system includes 8 DORV subtypes, categorized according to 3 factors: the relative positions of the great arteries (normal or abnormal), the relationship between the great arteries and the ventricular septal defect (committed or noncommitted), and the presence or absence of right ventricular outflow tract obstruction (RVOTO). Surgical approaches in 407 patients were based on their DORV subtype, as determined by echocardiography. We found that the optimal surgical management of patients classified as normal/committed/no RVOTO, normal/committed/RVOTO, and abnormal/committed/no RVOTO was, respectively, like that for patients with large ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries without RVOTO. Patients with abnormal/committed/RVOTO anatomy and those with abnormal/noncommitted/RVOTO anatomy underwent intraventricular repair and double-root translocation. For patients with other types of DORV, choosing the appropriate surgical approach and biventricular repair techniques was more complex. We think that our classification system accurately groups DORV patients and enables surgeons to select the best approach for each patient's cardiac anatomy.

Mustard baffle obstruction and leak - How successful are percutaneous interventions in adults?

Atrial switch operations for D-Transposition of the great arteries (D-TGA) were performed until the late 20th century. These patients have substantial rates of re-operation, particularly for baffle related complications. This study sought to analyze the efficacy of percutaneous transcatheter intervention (PTI) for baffle leak and/or stenosis in adult atrial switch patients. Adult patients with a prior atrial switch operation who underwent heart catheterization (2002-2014) at a tertiary adult congenital heart disease referral center were retrospectively analyzed. In 58 adults (30 ± 8 years, 75% men, 14% New York Heart Association (NYHA) functional class ≥2) who underwent 79 catheterizations, PTI was attempted in 50 (baffle leak (n = 10, 20%), stenosis (n = 27, 54%), or both (n = 13, 26%)). PTI was successful in 45 and 5 were referred for surgery due to complex anatomy. A total of 40 bare metal stents, 18 covered stents, 16 occlusion devices, 2 angioplasties, and 1 endovascular graft were deployed. In isolated stenosis, there was improvement in NYHA functional class after PTI (8 vs. 0 patients were NYHA FC > 2, p = 0.004), which was matched by improvement in maximal oxygen consumption on exercise testing (VO₂) (25.1 ± 5.4 mL/kg/min vs. 27.9 ± 9 mL/kg/min, p = 0.03). There were no procedure-related deaths or emergent surgeries in this cohort. This single-center cohort is the largest reported series of adult atrial switch operation patients who have undergone PTI for baffle stenosis and/or leak. We demonstrate that PTI with an expert multi-disciplinary team is a safe and effective alternative to surgery in adult patients with an atrial switch operation.

Endovascular Treatment for Superior Vena Cava Occlusion or Obstruction in a Pediatric and Young Adult Population

OBJECTIVES

The purpose of this research was to investigate the causes and symptoms of superior vena cava (SVC) obstruction or occlusion and report on the long-term results of transcatheter therapy.

BACKGROUND

Information on transcatheter therapy for SVC obstruction is limited.

METHODS

Superior vena cava catheterization interventions between August 1984 and April 2006 were reviewed. Patients were divided into 2 subgroups depending on whether or not they had previously undergone congenital cardiac surgery.

RESULTS

Sixty-three patients with median age of 3.7 years (range 1 month to 42 years) and weight of 13.3 kg (range 3 to 114 kg) were treated. Fifty patients (79%) were symptomatic, although only 50% had symptoms suggestive of SVC obstruction. Superior vena cava syndrome was more common in the non-cardiac surgical group (52% vs. 10%, p = 0.001). The mean gradient and SVC diameter improved from 10.8 +/- 5.8 mm Hg to 2.6 +/- 2.2 mm Hg (p < 0.001) and 3.1 +/- 2.7 mm to 9.1 +/- 3.8 mm, respectively (p < 0.001). The obstruction was adequately relieved in all 36 patients receiving stents and in 21 of 27 patients (78%) who had balloon dilation alone. Complications occurred in 12 patients (19%), all of whom had previously undergone cardiac surgery; 10 of these patients were successfully treated in the catheterization laboratory. Freedom from re-intervention did not differ between patients undergoing balloon dilation or stent implantation, but was longer in patients age >5 years at the time of intervention.

CONCLUSIONS

Superior vena cava-related symptoms occur in only 50% of patients with hemodynamically significant SVC obstruction. Endovascular therapy is successful in relieving the stenosis and associated symptoms with good long-term results.

Radiofrequency catheter ablation of supraventricular tachycardia substrates after mustard and senning operations for d-transposition of the great arteries

OBJECTIVES

The purpose of this study was to determine the efficacy and risks of radiofrequency ablation of various forms of supraventricular tachycardia after Mustard and Senning operations for d-transposition of the great arteries.

BACKGROUND

In this patient group, the reported success rate of catheter ablation of intraatrial reentry tachycardia is about 70% with a negligible complication rate. There are no reports of the use of radiofrequency ablation to treat other types of supraventricular tachycardia.

METHODS

Standard diagnostic criteria were used to determine supraventricular tachycardia type. Appropriate sites for attempted ablation included 1) intraatrial reentry tachycardia: presence of concealed entrainment with a postpacing interval similar to tachycardia cycle length; 2) focal atrial tachycardia: a P-A interval < or =-20 ms; and 3) typical variety of atrioventricular (AV) node reentry tachycardia: combined electrographic and radiographic features.

RESULTS

Nine Mustard and two Senning patients underwent 13 studies to successfully ablate all supraventricular tachycardia substrates in eight (73%) patients. Eight of eleven (73%) patients having intraatrial reentry tachycardia, 3/3 having typical AV node reentry tachycardia, and 2/2 having focal atrial reentry tachycardia were successfully ablated. Among five patients having intraatrial reentry tachycardia (IART) and not having ventriculoatrial (V-A) conduction, two suffered high-grade AV block when ablation of the systemic venous portion of the medial tricuspid valve/inferior vena cava isthmus was attempted.

CONCLUSIONS

Radiofrequency catheter ablation can be effectively and safely performed for certain supraventricular tachycardia types in addition to intraatrial reentry. A novel catheter course is required for slow pathway modification. High-grade AV block is a potential risk of lesions placed in the systemic venous medial isthmus.

Intraventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect: advantages of multiple patches

OBJECTIVE

The objective of this paper is to report our experience with biventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect by means of multiple patches that simplify and render feasible the intraventricular correction of this complex anomaly.

METHODS

From April 1987 to April 1999, in 18 patients with double-outlet right ventricle and noncommitted ventricular septal defect, a technical modification that used multiple patches of bovine pericardium was used to construct an intraventricular tunnel connecting the left ventricle to the aorta. Ages ranged from 2 months to 13 years (mean age 4.73 +/- 3.41 years).

RESULTS

The early mortality was of 11.1% (2 patients). Surviving patients were followed up for a mean of 2.65 years. Three late deaths (16.6%) occurred: 5 months, 7 months, and 7 months after the operation. All but 1 patient are in New York Heart Association class I.

CONCLUSION

The use of multiple patches for biventricular correction of this anomaly simplifies and renders feasible the intraventricular repair in cases in which the 1-patch technique was deemed impossible.

[Arrhythmias in patients with congenital heart disease and their impact on prognosis]

Patients with congenital heart disease have an increased chance to suffer from brady- as well as tachyarrhythmias. The impact of these on quality of life, morbidity and mortality is more often imperative as compared to heart-healthy individuals. The substrate for these may be either congenital or acquired. Improvements of the surgical management of these patients have led, on the one hand, to improved survival rates with prolonged life expectancy within the last 2 decades, which on the other hand provided the basis for a higher rate of acquired cardiac arrhythmias. Together, this not only challenges diagnostics and therapy but also the prognostic relevance of these arrhythmias. The therapeutic strategies and prognostic markers have until now mostly been based on retrospective studies limited by the low number of patients and inhomogeneous patient selection. Despite these limitations, an increased risk of sudden cardiac death has been substantiated for certain patient groups, e.g., those operated on by the Mustard- or Senning procedures in patients with transposition of the great arteries and patients operated on with correction of the tetralogy of Fallot. However, until now it has not been possible to identify reliable markers for establishing the risk on an individual basis within these patient cohorts. For achieving reliable data on the symptomatic and prognostic effects of present-day--as well as new-coming--therapeutic strategies, it is mandatory to perform prospectively based, randomized multicenter studies. Furthermore, the well-appreciated synergism of hemodynamically and primarily of arrhythmia-based effects on prognosis could potentially be divided into their relative weight to better guide appropriate, substrate-related therapy. In addition, this should help to get better estimates of the risk for sudden cardiac death in different, etiologically homogeneous, groups of patients with congenital heart disease.

Outcomes of transposition of the great arteries in the ear of atrial inflow correction

OBJECTIVE

To examine long term morbidity and mortality following atrial inflow corrective procedures for transposition of the great arteries (TGA) and to investigate factors that influence morbidity and mortality.

DESIGN

Retrospective cohort study from a single centre.

SETTING

Cardiology and cardiothoracic surgical unit in a large tertiary referral centre.

PATIENTS

All 130 patients who had TGA diagnosed between August 1972 and May 1988 and were considered suitable for atrial inflow correction; 109 of these underwent surgery (operative cohort: 84 Mustard operations and 25 Senning operations); 95 survived to hospital discharge (hospital surviving cohort).

MAIN OUTCOME MEASURES

Death and cardiac events.

RESULTS

There were relatively good long term results from atrial inflow correction for TGA with 5, 10, and 15 year survivals of 77.3%, 75.9%, and 71.3%. However, there was an appreciable incidence of late cardiac death and events, with 5, 10, and 15 year cardiac event-free survivals of 74.5%, 67.1%, and 39.6%. Supraventricular tachycardia was the only significant risk factor for late cardiac death (relative risk 8.72, 95% confidence interval, 2.86 to 26.64). Senning patients had better event-free survival (p = 0.04).

CONCLUSIONS

Atrial inflow correction for TGA has a reasonably good 15 year survival (71.3%), but there is an appreciable incidence of late cardiac deaths and events (15 year event-free survival 39.6%). The Senning procedure is preferable to the Mustard procedure for cases unsuitable for arterial switching.

Self expandable stents for relief of venous baffle obstruction after the Mustard operation

OBJECTIVE

Obstruction of the venous pathways after Mustard repair for transposition of the great arteries is associated with an increased risk of arrhythmia and sudden death. The purpose of this study was to assess the effectiveness of the largest (tracheal 22 x 40 mm) Wallstents in treating baffle obstructions.

DESIGN

Retrospective analysis of patients with stented venous pathways.

SUBJECTS

Eleven patients with baffle obstruction after Mustard repair for transposition of the great arteries.

INTERVENTIONS

Stenoses were dilated with an 18 or 20 mm balloon. However, recoil was noticed in 11 patients: immediately (n = 7) or on repeat angiography (n = 4). Eighteen stents were implanted (mean (SD)) 18 (3.3) years postoperatively. After dilatation a tracheal Wallstent (11.5 F) was deployed.

MAIN OUTCOME MEASURES

Relief of obstruction, haemodynamic improvement.

RESULTS

In the inferior vena cava, 10 stents were deployed in seven baffle obstructions with an increase in diameter from 9.8 (2.4) mm to 16.5 (1.4) mm (p < 0.01) and a mean (SD) pressure gradient decrease from 5.1 (3.6) mm Hg to 1.4 (2.0) mm Hg; in the superior vena cava, eight stents were implanted increasing the diameter from 9.1 (3.7) mm to 15.6 (3.8) mm (p < 0.001) with a decrease in mean pressure gradient from 5.1 (2.7) mm Hg to 1.9 (1.5) mm Hg. No complications were experienced during implantation. No anticoagulation was prescribed. During follow up (1.7 (0.6) years; range, 0.9-2.6) no problems were noted; five patients were re-catheterised without change in measurements. There was no evidence of peal formation in any of the stents.

CONCLUSION

It is concluded that Wallstents are safe, easy to use, and effective in relieving baffle obstruction. Anticoagulation does not seem necessary.

Right ventricular function in congenital heart disease: pressure and volume overload lesions

The right ventricle is often subject to both pressure and volume overload in congenital heart disease. Evaluating right ventricular function in both the native lesion and after surgery in light of these loading conditions, presents a unique challenge for investigators studying these misshapen hearts. The purpose of this article is to briefly delineate what is generally known about right ventricular function in congenital heart disease and to touch on some noninvasive imaging modalities which have helped shed some light on this matter.

Arrhythmia and mortality after the Mustard procedure: a 30-year single-center experience

OBJECTIVES

Our purpose was to assess the risk factors for late mortality, loss of sinus rhythm and atrial flutter after the Mustard operation.

BACKGROUND

The Mustard operation provides correction of cyanosis with low surgical risk in transposition of the great vessels. However, right ventricular failure, loss of sinus rhythm, atrial flutter and death are frequent long-term complications.

METHODS

Records of 534 children who underwent the Mustard operation at a single center since 1962 were reviewed for demographic, anatomic, electrocardiographic and physiologic predictors and outcomes.

RESULTS

There were 52 early deaths (9.7%). Survival analysis was undertaken for 478 early survivors with a mean follow-up interval of 11.6 +/- 7.2 years. There were 77 late deaths (16.1%), with sudden death (n = 31) the most frequent cause. Survival estimates were 89% at 5 years and 76% at 20 years of age. Risk factors were an earlier date of operation, operative period arrhythmia and an associated ventricular septal defect. Risk (hazard) of late death declined in the first decade, with further peaks in the second decade. Sinus rhythm was present in 77% at 5 years and 40% at 20 years. Loss of sinus rhythm was associated with previous septectomy, postoperative bradycardia and late atrial flutter. Freedom from atrial flutter was 92% at 5 years and 73% at 20 years of age. Risk factors for atrial flutter were the occurrence of perioperative bradyarrhythmia, reoperation and loss of sinus rhythm during follow-up. Risk of atrial flutter demonstrates a late increase.

CONCLUSIONS

Ongoing loss of sinus rhythm and late peaks in the risk of atrial flutter and death necessitate continued follow-up.

Successful term pregnancy after Mustard operation for transposition of the great arteries

Transposition of the great arteries is a complex cardiac malformation with poor prognosis without surgical correction. Since the introduction of surgical procedures such as the intra-auricular reorientation of the venous return (Mustard procedure), an increasing number of patients may reach adulthood and experience pregnancy. Because long-term complications after the Mustard operation include systemic heart failure, arrhythmias, venous return stenosis and pulmonary edema, hemodynamic changes during pregnancy and delivery may potentially engender life-threatening complications in these patients. We report the case of a 24-year-old primigravida who underwent a Mustard procedure at the age of 2 years for transposition of the great vessels, and who carried out a full-term pregnancy. The pregnancy was uneventful until the 34th week, when the woman developed signs of moderate right ventricular failure and frequent episodes of accelerated junctional rhythm. Digitalisation improved symptoms and elicited return to normal sinus rhythm. The patient delivered at term by elective cesarean section, under close hemodynamic monitoring.

Late follow-up after venous switch operation (Mustard procedure) for simple and complex transposition of the great arteries

Most adolescents and young adults born with complete transposition of the great arteries (TGA) and alive today are survivors of the Mustard operation. This study reports on the serial, long-term (from 10 to > 20 years) follow-up of 85 patients who underwent this operation between 1971 and 1981. Of these, 63 had simple and 22 complex TGA. The age at surgery ranged from 2 days to 17 years. The early mortality rate was 10.5% and the late mortality 9.2%. The actuarial survival rate after 15 years was 86% for simple and 64% for complex TGA. Event-free survival after 15 years was 77% for simple and 46% for complex TGA. Yearly review of electrocardiograms and, less frequently, of Holter tracings disclosed a lower mean resting heart rate and decrease over time in sinus rhythm and an increase in active arrhythmias. Fifty-two percent had resting sinus rhythm and 17% had active arrhythmias at 16 to 20 years of follow-up. Exercise stress testing in 21 patients revealed resumption of sinus rhythm during exercise but significant diminution of endurance time and peak heart rate response. Seven of the survivors (9.2%) required reoperation. Of these, 4 had severe tricuspid regurgitation following patch closure of ventricular septal defect. This study shows gratifying long-term and event-free survival for the majority of patients who underwent surgery by this venous switch procedure.

Medium-term clinical results after the Senning procedure with haemodynamic and angiographic evaluation of the venous pathways

OBJECTIVE

To assess the clinical condition of patients and the adequacy of their newly constructed venous pathways after the Senning operation for simple transposition of the great arteries.

PATIENTS AND DESIGN

All 34 patients who had the Senning operation between March 1983 and December 1986 were reviewed. Survivors had detailed cardiac catheterisation studies one to two years later and clinical evaluation two to six years after surgery.

RESULTS

There were two operative deaths (6%), one sudden late death (after two years), and 31 survivors (91%). No clinical evidence of obstructed venous pathways was found and there was no need for reoperation for any reason. The average mean (SD) pressure gradient at the junction of the superior vena cava and systemic venous atrium was 2.0 (1.7) mm Hg, although two patients had gradients of 7 mm Hg. The average gradient was 0.7 (1) mm Hg in the inferior vena caval pathway, and 1.4 (1.1) mm Hg between the mean pulmonary arterial wedge and pulmonary venous atrial pressures. Only the two patients with gradients of 7 mm Hg at the junction of the superior vena cava and the systemic venous atrium had considerable narrowing of the pathway and retrograde flow in the azygos vein to below the diaphragm.

CONCLUSION

A small series of patients were comprehensively studied after the Senning operation for simple transposition of the great arteries. Scrupulous technique in the construction of the venous pathways has had excellent results with no need for reoperation for obstruction in either the systemic or pulmonary pathways. Clinical observation alone may fail to identify patients with venous pathway obstruction, therefore careful assessment is required, even in patients who are physically normal.

The Senning operation for complete transposition: mid-term physiologic, electrophysiologic, and functional results

SummaryWe report analysis of surgical results in 110 consecutive infants and children who underwent atrial repair of simple complete transposition using the Senning operation between February 1978 and May 1990. Mean age at operation was 5.4 months ± 6.1 (range 1 week to 4 years); 75 were less than 6 months old. There were 72 males and 38 females. Operative mortality rate was 5.5%, with one late death. Average follow-up is 48.1 months with 44 followed greater than 3 years, and 27 greater than 5 years. Postoperative cardiac catheterization was performed in 48 patients. Right ventricular ejection fraction averaged 0.52 ± 0.08 and was normal in 28 patients. Response of right ventricular ejection fraction to afrerload stress was abnormal in 12 of 14 patients tested. Right ventricular ejection fraction increased normally during exercise in 6 patients, but was abnormal in 15. Mild tricuspid regurgitation was noted in 12 patients. Mild obstruction of the superior caval vein was noted in 4 patients. Baffle leak requiring reoperation occurred in one patient. Fifty-seven of 90 patients are in sinus rhythm by latest electrocardiogram. Postoperative electrophysiologic studies were performed in 34 patients, and Holter monitoring in 25. Significant arrhythmia occurred in 26 patients: 6 patients required pacemakers for slow junctional rhythm or complete heart block; 20 additional patients have a junctional rhythm. Six patients have delayed sinus nodal recovery time. At last follow-up, 88 children (98%) are in New York Heart Association functional Class I, and 2 (2%) are in Class II. The Senning operation for compete transposition can be accomplished with a low operative and late mortality. Serious baffle complications requiring reoperation are rare. Surviving patients are clinically well, but arrhythmias and depressed right ventricular function may limit their long-term functional status.

Factors influencing choice of procedure in transposition of the great arteries: a decision analysis approach

Clinicians have a difficult choice between the arterial switch (Jatene et al.) and the atrial baffle operation (Mustard or Senning) for transposition of the great arteries. The surgical decision is essentially a determination of whether the long-term course after the arterial switch procedure (thought to be more favorable than after the atrial baffle procedure) plus elimination of presurgical attrition with the atrial baffle is substantial enough to offset the higher early mortality rate associated with the arterial switch. Decision analysis was undertaken to answer the following questions: 1) are there clinical circumstances under which published surgical results support a clear procedure of choice in transposition of the great arteries? and 2) what short- and long-term outcomes must be anticipated for the arterial switch to compare favorably with the published experience with the atrial baffle? A decision tree was constructed accounting for the major variables influencing mortality and morbidity in the surgical management of transposition of the great arteries. Presuming that the arterial switch has moderate advantages over the atrial baffle in terms of late morbidity and mortality for simple transposition of the great arteries at an institution with average results from the atrial baffle, the early mortality rate of the arterial switch must be less than 24% to recommend the switch operation. Assuming extremely good surgical results from the atrial baffle, an early mortality rate of the arterial switch less than 20% is required to recommend the switch procedure over the atrial baffle operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Sudden death after repair of double-outlet right ventricle

The outlook for patients with double-outlet right ventricle has improved since the development of corrective operations. Late arrhythmic deaths after successful procedures have been reported; however, the magnitude remains unknown. This study was undertaken to identify the magnitude of late sudden death and the significant factors associated with it. From 1965 through 1985, 118 patients underwent corrective operation for double-outlet right ventricle; of these, 23 died in the hospital and six were lost to follow-up. The 89 remaining patients (52 male and 37 female) made up the study population. Their mean age (+/- SD) was 10.3 +/- 7.8 years at the time of repair. The mean duration of follow-up was 82 months. Of the 22 late deaths, 16 (73%) were sudden. Eight (50%) of the sudden deaths occurred within 1 year of operation. Cox proportional hazards multivariate analysis revealed the following significant risk factors for late sudden death: older age at the time of operation, perioperative or postoperative ventricular tachyarrhythmias, and third-degree atrioventricular block. Factors not associated with late sudden death included year of operation, sex, type and number of associated cardiac anomalies, preoperative functional class, previous palliative procedures, surgical technique, perioperative or postoperative single premature ventricular contractions, and postoperative left or right bundle branch block with or without fascicular block. We conclude that the incidence of late sudden death after successful surgical repair of double-outlet right ventricle is very high. Complete corrective operation at an early age and aggressive diagnosis and treatment of arrhythmias and conduction defects after operation are warranted.

Ten years' experience with the Senning operation for transposition of the great arteries: physiological results and late follow-up

We report our results in 93 consecutive infants and children who underwent atrial repair of simple transposition of the great arteries using the Senning operation between February 1978 and February 1988. Mean age at operation was 5.6 +/- 6.3 months (range, 1 week to 4 years); 60 were less than 6 months old. There were 65 boys and 28 girls. Operative mortality was 5.4%, and there has been 1 late death. Average follow-up is 45.1 months with 39 followed more than 3 years and 25 followed more than 5 years. Postoperative cardiac catheterization was performed in 43 patients. Right ventricular ejection fraction at rest averaged 0.50 +/- 0.09 and was normal in 26 patients. Response of right ventricular ejection fraction to afterload stress was abnormal in 12 of 14 patients tested. Right ventricular ejection fraction increased normally during exercise in 6 patients, but was abnormal in 15. Mild tricuspid regurgitation was noted in 10 patients. Mild obstruction of the superior vena cava was noted in 4 patients. Baffle leak requiring reoperation occurred in 1 patient. Seventy-two of 80 patients are in sinus rhythm by latest electrocardiogram. Postoperative electrophysiological studies were performed in 34 patients and Holter monitoring was performed in 22. A major arrhythmia occurred in 8 patients: 3 required a pacemaker for junctional rhythm or sinus node dysfunction, 2 have symptomatic or inducible supraventricular tachycardia, 2 have junctional rhythm, and 1 has sick sinus syndrome. Eight additional patients have delayed sinus node recovery time. At last follow-up, 78 children (97.5%) are in New York Heart Association functional class I, and 2 (2.5%) are in class II.(ABSTRACT TRUNCATED AT 250 WORDS)

Results with the Mustard operation in simple transposition of the great arteries 1963-1985

From May 1963 to December 1985, 329 infants and children underwent repair of simple transposition of the great arteries (TGA) using Mustard's technique. To assess improvement, the patients were separated into two groups by date of operation: Group I, May 1963 to December 1973 (N = 106), and Group II, January 1974 to December 1985 (N = 223). The operative mortality was 11 (10.4%) in Group I and two (0.9%) in Group II. The 10-year actuarial survival rate was 73.4% in Group I and 93.7% in Group II. Baffle complications, similar in both groups, were identified in 81 patients; 19 were major, causing death or requiring reoperation. By latest electrocardiogram, 21 of 45 (46.7%) of Group I patients and 129 of 180 (71.7%) of Group II patients were in normal sinus rhythm. Late ambulatory electrocardiography, however, revealed that a majority of patients had sinus node dysfunction or other dysrhythmias. Right ventricular (RV) angiography revealed definite diminution of RV contractility in 14 (11%) of 126 children. At late follow-up, 113 of 148 (76%) children were in New York Heart Association (NYHA) Class I and 35 of 148 (24%) were in NYHA Class II. Thirty-five (21%) patients were on cardiac medication chiefly for dysrhythmia management. There has been significant improvement in the early and late mortality with the Mustard operation, and serious baffle complications are infrequent. Dysrhythmias continue to be a major problem but the surviving patients are clinically well and relatively few have significant RV dysfunction.