Christian P. Brizard

The Fontan Procedure Contemporary Techniques Have Improved Long-Term Outcomes

Background— To determine whether patients undergoing the lateral tunnel and extracardiac conduit modifications of the Fontan procedure have better outcomes than patients undergoing a classical atriopulmonary connection. Methods and Results— Between 1980 and 2000, 305 consecutive patients underwent a Fontan procedure at our institution. There were 10 hospital deaths (mortality: 3%) with no death after 1990. Independent risk factors for mortality were preoperative elevated pulmonary artery pressures (P=0.002) and common atrioventricular valve (P=0.04). Fontan was taken down during hospital stay in 7 patients. A mean of 12±6 years of follow-up was obtained in the 257 nonforeign Fontan survivors. Completeness of concurrent follow-up was 96%. Twenty-year survival was 84% (95% CI: 79 to 89%). Recent techniques improved late survival. The 15-year survival after atriopulmonary connection was 81% (95% CI: 73% to 87%) versus 94% (95% CI: 79% to 98%) for lateral tunnel (P=0.004). Nine pts required heart transplantation (8 atriopulmonary connection, 1 lateral tunnel). Undergoing a Fontan modification independently predicted decreased occurrence of arrhythmia, and 15-year freedom from SVT was 61% (95% CI: 51% to 70%) for atriopulmonary connection versus 87% (95% CI: 76% to 93%) for lateral tunnel (P=0.02). Freedom from Fontan failure (death, take-down, transplantation, or NYHA class III-IV) was 70% (95% CI: 58% to 79%) at 20 years. After extra-cardiac conduits, no death, SVT, or failure was observed. Conclusions— The Fontan procedure remains a palliation, but outcomes of patients have improved. Better patient selection minimizes hospital mortality. Patients with lateral tunnel and extracardiac conduit modifications experience less arrhythmia and are likely to have failure of their Fontan circulation postponed.

New White Matter Brain Injury After Infant Heart Surgery Is Associated With Diagnostic Group and the Use of Circulatory Arrest

Background— Abnormalities on magnetic resonance imaging scans are common both before and after surgery for congenital heart disease in early infancy. The aim of this study was to prospectively investigate the nature, timing, and consequences of brain injury on magnetic resonance imaging in a cohort of young infants undergoing surgery for congenital heart disease both with and without cardiopulmonary bypass. Methods and Results— A total of 153 infants undergoing surgery for congenital heart disease at <8 weeks of age underwent serial magnetic resonance imaging scans before and after surgery and at 3 months of age, as well as neurodevelopmental assessment at 2 years of age. White matter injury (WMI) was the commonest type of injury both before and after surgery. It occurred in 20% of infants before surgery and was associated with a less mature brain. New WMI after surgery was present in 44% of infants and at similar rates after surgery with or without cardiopulmonary bypass. The most important association was diagnostic group (P<0.001). In infants having arch reconstruction, the use and duration of circulatory arrest were significantly associated with new WMI. New WMI was also associated with the duration of cardiopulmonary bypass, postoperative lactate level, brain maturity, and WMI before surgery. Brain immaturity but not brain injury was associated with impaired neurodevelopment at 2 years of age. Conclusions— New WMI is common after surgery for congenital heart disease and occurs at the same rate in infants undergoing surgery with and without cardiopulmonary bypass. New WMI is associated with diagnostic group and, in infants undergoing arch surgery, the use of circulatory arrest.

Excellent long-term functional outcome after an operation for anomalous left coronary artery from the pulmonary artery

OBJECTIVE The aim of this study was to review the results of operations for anomalous left coronary artery from the pulmonary artery and the late outcome for exercise capacity, left ventricular function, and mitral regurgitation. METHODS Twenty-one patients underwent operations over an 18-year period (median age, 9 months; range, 6 weeks-26 years) with a median follow-up of 6.5 years (range, 2 months-18 years). In addition to clinical and echocardiographic follow-up, patients at our institution were also investigated with radionuclide scans (n = 10) and treadmill exercise testing (n = 8). RESULTS There were no operative or late deaths (0%; 95% confidence interval [CI], 0% and 16%). Five patients required support with a left ventricular assist device. Eighteen patients are currently in New York Heart Association class I, and 3 patients are mildly symptomatic. On nuclear gated scan at a mean of 6 years after the operation, the left ventricular ejection fraction was 64% (SD, 3%) at rest and increased to 74% (SD = 3%) on exercise (95% CI for the difference, 6%, 14%; P =.001). Treadmill endurance was normal for age (9.8-14.5 minutes) in those old enough to exercise. On echocardiography (n = 18), the current fractional shortening was 34% (SD, 4%) in the 15 patients with normal or only mildly abnormal ventricular septal motion. Three patients have undergone mitral valve operations. The left ventricular end-diastolic dimension fell from 48 mm (SD, 5.8 mm) before surgery to 35.1 mm (SD, 5.2 mm) at 1 year after the operation, and the fractional shortening increased over the first year from 19.6% (SD, 9.3%) to 32.8% (SD, 5.9%; both P <.001). CONCLUSIONS Long-term clinical outcome and left ventricular function are good, despite severe left ventricular dysfunction at presentation.

Experience with the Jostra Rotaflow and QuadroxD oxygenator for ECMO.

Since April 1988, we have been able to offer extracorporeal membrane oxygenation (ECMO) to patients who are either failing ventilation or who need cardiopulmonary support following cardiac surgery. During this time, we have supported 211 patients, the majority of whom have been supported with the Avecor (Affinity, Avecor Cardiovascular Inc., Minneapolis, MN, USA) spiral wound silicone-membrane oxygenator. Microporous hollow-fibre oxygenators have been used (18%) at our center. However, due to their early failure, they have necessitated conversion to a device that potentially would last for the entire ECMO course, i.e., Avecor and, subsequently, have not been used routinely until the introduction of the QuadroxD (Jostra Medizintechnik AG, Hirrlingen, Germany). The recent development of the poly-4-methyl-1-pentene diffusion membrane allows us to utilize hollow-fibre technology with a true (nonmicroporous) membrane. This has enabled us to use this low-resistance device with all its inherent advantages, without plasma leakage necessitating circuit changeover. From July 2000, we have used the QuadroxD oxygenator for our patients requiring ECMO support. This has been in patients with weights ranging from 2.16-51.0 kg (n = 23), with the longest support being for 1119 hours. This new technology has enabled us to utilize a single device for all patient sizes, so we now have an ECMO circuit set up at all times, minimizing the time required for support to be available, potentially improving survivor morbidity.

Outcomes of the Arterial Switch Operation for Transposition of the Great Arteries: 25 Years of Experience

BACKGROUND Studies on long-term outcomes of the arterial switch operation (ASO) for transposition of the great arteries (TGA) are uncommon. Thus, we sought to determine the long-term outcomes for patients after ASO performed at a single institution over a 25-year period. METHODS From 1983 to 2009, 618 patients underwent the ASO for TGA and were reviewed retrospectively. RESULTS Overall early mortality was 2.8%. Risk factors for early death on multivariate analysis were resection of left ventricular outflow tract obstruction at time of ASO (p = 0.001), weight less than 2.5 kg at time of ASO (p < 0.001), associated aortic arch obstruction (p = 0.043), and the need for postoperative extracorporeal membrane oxygenation (p < 0.001). Mean follow-up time was 10.6 years (range 2 months to 26.1 years). Late mortality was 0.9%. Reintervention was significantly higher (p < 0.001) in patients with ventricular septal defect or arch obstruction versus those without them (25.2% and 23.4% vs 5.9% at 15- year follow-up). Risk factors for late reintervention were left ventricular outflow tract obstruction at time of ASO (p < 0.001) and a greater circulatory arrest time (p < 0.001). Freedom from at least moderate neoaortic valve regurgitation for the entire cohort was 98.7% (95% confidence interval 96.8 to 99.5%) at 20 years. Mild neoaortic regurgitation was seen in 25.6% of patients at mean follow-up. All patients were free of arrhythmia and heart failure symptoms at last follow-up. CONCLUSIONS The ASO can be performed with good long-term results. Patients with associated ventricular septal defect and aortic arch obstruction warrant close follow-up.

Predictors of survival after single-ventricle palliation: the impact of right ventricular dominance.

OBJECTIVES This study examined survival after surgical palliation in children with single-ventricle physiology. BACKGROUND Contemporary surgical outcomes for the entire population of newborns undergoing single-ventricle palliation are unclear. METHODS In a single-center review of 499 consecutive patients undergoing univentricular palliation from 1990 to 2008, predictors of mortality were determined using multivariate risk analysis, stratified for each post-operative stay and interim states. RESULTS After 2000, the population comprised more patients with dominant right ventricle (66% vs. 36%) and hypoplastic left heart syndrome (HLHS) (47% vs. 13%). Median age at bidirectional cavopulmonary shunt (BCPS) decreased from 15 months (10 to 22 months) before 2000 to 4 months (3.3 to 9 months) thereafter. Survival rates at 1, 5, and 10 years were, respectively, 82% (95% confidence interval [CI]: 79% to 85%), 74% (95% CI: 70% to 78%), and 71% (95% CI: 67% to 75%). Throughout the study, atrioventricular valve regurgitation (hazard ratio [HR]: 1.8; p = 0.008), not having transposition (HR: 2.0; p = 0.013), and heterotaxia (HR: 2.0; p = 0.026) were predictors of mortality. The most potent risk factor was right ventricular (RV) dominance (HR: 2.2; p = 0.001) because of its impact before BCPS. HR for death in patients with RV dominance went from 2.8 (95% CI: 1.4 to 5.7; p = 0.005) before BCPS to 1.0 (95% CI: 0.5 to 2.1; p = 0.98) thereafter. Survival of patients with RV dominance, adjusted for the risk factors noted here, improved over the study period (p = 0.001). CONCLUSIONS Considerable mortality is still observed during the first years of life among patients with single ventricle. RV dominance is the most important risk factor for death but only before BCPS.

Centrifugal ventricular assist in children under 6 kg

OBJECTIVE The clinical application of centrifugal ventricular assist devices (VAD) has generally been limited to adults and large paediatric patients. In our experience neonates and small paediatric patients requiring ventricular support post-cardiopulmonary bypass are well supported by VAD. In this study we analyse our experience. METHODS We have examined the records of our VAD patients who weighed less than 6 kg. Thirty-four patients, ranging in age from 2 to 258 days (median 60 days) and weight from 1.9 to 5.98 kg (median 3.7 kg), underwent 35 VAD procedures. One patient was supported on VAD twice. RESULTS All patients had congenital heart lesions and were placed on VAD either because they could not be weaned from cardiopulmonary bypass after repair or palliation of the lesion (71.5%), or for support in the post-operative period due to refractory low cardiac output (28.5%). Twenty-two of the 35 VAD procedures (0.63, 95% CI: 0.45-0.78) resulted in successful weaning and decannulation, this was similar to the weaning probability for patients greater than 6 kg (P = 0.07). There were 10 late deaths in this group, with a 1-year KM survival of 0.31 (95% CI: 0.17-0.47). Most late deaths were related to irreversible cardiac disease processes as were the elective discontinuance of VAD outcomes. Neither weight, age, VAD duration, CPB duration, X clamp duration, univentricular anatomy or TGA anatomy predicted successful discharge from hospital (P > 0.05)--Weight P = 0.576; Age P = 0.532; VAD duration P = 0.181; CBP duration P = 0.549; X clamp duration P = 0.984; Univentricular anatomy P = 0.481; TGA anatomy P = 0.099. CONCLUSION We believe centrifugal ventricular assist is a realistic option in very small patients who require post-cardiopulmonary bypass support. It is relatively easy to establish and manage, the results, although showing no factors predictive of successful discharge, are encouraging.

Improved early ventricular performance with a right ventricle to pulmonary artery conduit in stage 1 palliation for hypoplastic left heart syndrome: evidence from strain Doppler echocardiography

Objective: To quantify non-invasively right ventricular (RV) performance in infants after stage 1 palliation for hypoplastic left heart syndrome (HLHS). Design: Prospective, observational study with two dimensional and strain Doppler echocardiography. Setting: Single tertiary paediatric cardiology centre. Patients: Convenience sample of nine consecutive infants with HLHS. Four whose surgery involved a systemic to pulmonary artery (S-PA) shunt were compared with five whose surgery incorporated a right ventricle to pulmonary artery (RV-PA) conduit. Methods: Basal RV free wall longitudinal strain rate, systolic strain (ϵ), and RV percentage area change were calculated during a single assessment between 27–50 days after surgery. Results: Cardiopulmonary bypass time was longer in patients who underwent RV-PA (226 (30) minutes v 181 (18) minutes, p  =  0.03), but cross clamp time, duration of ventilation, and inotrope use did not differ. Two patients in the S-PA group died, on days 29 and 60 after surgery. Peak systolic strain rate (−1.24 (0.19)/s v −0.91 (0.21)/s, p  =  0.048), peak ϵ (−17.8 (1.8)% v –13.4 (2.0)%, p  =  0.01), and RV percentage area change (56 (6)% v 25 (6)%, p < 0.01) were all greater among RV-PA patients. These indices also tended to be greater in survivors as a group. Ventricular loading conditions (oxygen saturations, diuretic treatment, and blood pressure) were similar in both groups. Conclusion: Strain Doppler echocardiography shows improved RV longitudinal systolic contractility in patients during convalescence after the RV-PA modification of stage 1 palliation for HLHS compared with those with an S-PA shunt.

Surgical treatment of congenital mitral valve disease: Midterm results of a repair-oriented policy

OBJECTIVE Management of congenital mitral valve disease is challenging because of a wide morphologic spectrum, frequent associated lesions, and small patient size. We evaluated the results of a repair-oriented policy. METHODS All consecutive patients with congenital mitral valve disease who underwent surgery between 1996 and 2006 were studied retrospectively. Patients with atrioventricular canal, atrioventricular discordance, or ischemic regurgitation were excluded. RESULTS During this period, 71 children (median age 2.9 years, range 3 days-20.8 years) underwent surgery. All but 1 underwent primary mitral valve repair. Twenty-two (30%) were younger than 12 months. Associated cardiac lesions were present in 45 children (63%) and were addressed concurrently in 35; previous cardiac procedures had been performed in 17 patients (24%). Mitral incompetence was predominant in 60 (85%) and stenosis in 11 (15%). During a median follow-up of 47.8 months (range 2-120 months), 14 patients underwent 17 mitral reinterventions: 14 repairs and 3 replacements. After 60 months, overall survival was 94% +/- 2.8%; freedoms from reoperation and prosthesis implantation were 76% +/- 5.6% and 94% +/- 3.6%, respectively. There were 4 deaths, and all survivors remain in New York Heart Association class I or II with moderate (6 patients) or less mitral dysfunction. CONCLUSION Surgical repair of the congenital mitral valve can be successfully performed with low mortality, satisfactory valvular function at midterm follow-up, and acceptable reoperation rate while obviating risks associated with valvular prostheses. Suboptimal primary repair was significant predictor for reoperation but re-repair was often successful.

Impact of antenatal diagnosis of hypoplastic left heart syndrome on the clinical presentation and surgical outcomes: The Australian experience

Aim:  Antenatal diagnosis of severe congenital heart disease enables planning of perinatal care of affected infants. Congenital heart surgery is highly centralised in Australia, and surgery for hypoplastic left heart syndrome (HLHS) currently takes place at a single institution, in order to ensure case volume. The study aims to review the impact of antenatal diagnosis on the early clinical course of infants with HLHS in Australia.