Ten-year experience with the arterial switch operation.

BACKGROUND: Arterial level repair is considered the most appropriate procedure for transposition of the great arteries. This report describes our experience with the arterial switch operation over the past decade. METHODS AND RESULTS: From January 1991 to January 2001, a total of 299 patients underwent an arterial switch operation for transposition of the great arteries or double-outlet right ventricle. Group I (n=169, 56.5%) comprised patients with transposition of the great arteries in whom the ventricular septum was essentially intact. Group II patients (n=130, 43.5%) had transposition of the great arteries with an additional significant ventricular septal defect or had double-outlet right ventricle with a subpulmonic ventricular septal defect. Of the total, 245 (82%) were males and 54 (18%) were females. In group I, the ages ranged from 2 days to 18 years (median 19 days) and weight ranged from 1.7 to 68 kg (median 2.5 kg). In group II, the ages ranged from 4 days to 4 years (median 90 days) and weight ranged from 2.5 to 17 kg (median 4 kg). Fifteen percent of the patients (25/169) in group I and 30% of the patients (39/130) in group II had features of bacteriologic infection. Arterial switch operation was performed on standard lines. In group I, 141 patients (83.4%) had a primary arterial switch operation while 28 (16.6%) underwent a rapid two-stage repair. Twenty-three patients required concomitant relief of associated anatomic left ventricular outflow tract obstruction. Operative mortality was 8.8% (15/169) in group I and 33% (44/130) in group II with an overall mortality of 19% (59/299). The major causes of operative mortality included pulmonary arterial hypertensive crisis (n=21), sepsis and related complications (n=16), and left ventricular failure (n=8). Coexisting arch anomalies, longer cross-clamp time, late presentation, and preoperative bacteriologic infections were incremental risk factors. Follow-up ranged from 1 to 10 years and was 87% complete. On follow-up, 91% of the patients were asymptomatic and off all medications. There were 3 late deaths and 5 patients required reoperation. CONCLUSIONS: Excellent long-term results are obtained in operative survivors following the arterial switch operation. However. operative mortality remains a concern in our set-up.

Graded balloon atrial septostomy in severe pulmonary hypertension.

BACKGROUND: The prognosis of patients with severe primary pulmonary hypertension is poor. The role of balloon atrial septostomy as a palliative procedure in these patients is not well defined. We retrospectively analyzed our data regarding the safety, clinical outcome and survival benefit of graded balloon atrial septostomy in patients with severe pulmonary hypertension. METHODS AND RESULTS: Eleven patients (7 males), aged 6 to 30 years (mean age 16.2+/-8.9 years), with severe pulmonary artery hypertension (mean pulmonary artery pressure of 76+/-16.9 mmHg) and refractory congestive heart failure and/or recurrent syncope underwent balloon atrial septostomy. Graded balloon dilatation under echocardiographic guidance and arterial oxygen saturation monitoring was done in all the patients. Procedure-related mortality was 18.2%. Significant acute hemodynamic improvement was seen in the survivors (pre-balloon atrial septostomy cardiac index 1.88+/-0.48 L/min/m2; post-balloon atrial septostomy cardiac index 2.18+/-0.37 L/min/m2, p<0.009). Patients were followed up for a mean period of 20.3 months after the procedure (range: 3 months-5 years). There was functional improvement and increased exercise tolerance in all the patients for a mean follow-up period of 14.6 months (NYHA functional class 3.62+/-0.69 to 2+/-0.50). The estimated probability of survival in this cohort at 1 year was only 48%; but 7 of 8 patients (87%) who survived the procedure were alive at 1 year. CONCLUSION: We conclude that balloon atrial septostomy improves clinical status, hemodynamic variables and possibly also improves survival in selected patients with severe pulmonary artery hypertension. It remains a definite palliative option for refractory primary pulmonary hypertension. However, the procedure-related risks are high in very sick patients and, therefore, balloon atrial septostomy may be advocated early in the course of the disease.

Management of cardiomyopathy resulting from incessant supraventricular tachycardia in infants and children.

BACKGROUND: Radiofrequency ablation is considered to be the treatment of choice in patients with ventricular dysfunction related to incessant supraventricular tachycardia. However, reservations regarding its use in infants and children prompted us to try alternative strategies for this group. METHODS AND RESULTS: Eight children (age range: 1 day to 10 years) were diagnosed to have tachycardia-related ventricular dysfunction in the past 6 years. They presented with symptoms of palpitation, dyspnea and/or generalized swelling over the body of 3 months to 2 years'duration. The cardiothoracic ratio at presentation was 64% (52%-70%) and ejection fraction was 22.2% (15%-45%). In 7 patients tachycardia was diagnosed to be ectopic atrial and in 1 it was permanent junctional reciprocating tachycardia. Six of these children were managed with intravenous/oral amiodarone in combination with digoxin (3) and/or propranolol (2). In one child addition of amiodarone to digoxin and propranolol led to polymorphic ventricular tachycardia, and amiodarone was withdrawn. Only one child underwent radiofrequency ablation as the first choice because regular follow-up was not possible due to logistic reasons. Sinus rhythm with normalization of ventricular function was achieved in 6 of the 7 children treated medically. One child continued to have frequent episodes of tachycardia and underwent successful radiofrequency ablation of a high right atrial ectopic focus. Two out of the 6 patients on amiodarone could be managed with only digoxin and propranolol after their ventricular function had returned to normal. A third patient relapsed on stopping amiodarone and underwent successful radiofrequency ablation of a left atrial ectopic tachycardia. CONCLUSIONS: Short-term amiodarone in combination with digoxin/propranolol is a safe and effective treatment strategy for infants/children with tachycardiomyopathy. Control of tachycardia is achieved in the majority, leading to recovery of ventricular function. This approach may avoid unnecessary ablations in children or at least postpone it till the procedure would be safer.

Total anomalous pulmonary venous connection: surgical experience in Indians.

BACKGROUND: We report a retrospective analysis of the demographic. morphological and clinical profiles of patients along with results of operative repair for total anomalous pulmonary venous connection. METHODS AND RESULTS: In the last 15 years, 248 patients (168 boys, 80 girls) underwent repair for total anomalous pulmonary venous connection. Their ages ranged from I day to 24 years (median 8 months) and 145 of them were < or = 1 year of age. The patients' weight ranged from 2 to 52 kg (median 5 kg). About 70% of patients (n = 174) were less than the 50th percentile of predicted weight for age and sex. The anomalous connection was supracardiac in 134 (54%), cardiac in 80 (32.2%), infracardiac in 9 (3.6%) and mixed in 25 (10.1%) patients. Fifty (20.2%) patients had obstructed drainage and 76 patients (30.2%) had moderate or severe pulmonary arterial hypertension. Forty-five patients (18.1%) had to be operated upon on an emergency basis. All the patients were operated upon using moderately hypothermic cardiopulmonary bypass. In 114 patients, circulatory arrest was used. There were 45 (19.1%) in-hospital deaths. The major causes of early death were pulmonary arterial hypertensive crisis in 19 (7.7%) and low cardiac output syndrome in 17 (6.9%) patients. Age < or = 1 year (odds ratio 2.16; 95% confidence interval: 1.22-3.82, p=0.008), severe pulmonary arterial hypertension (odds ratio 5.86; 95% confidence interval: 2-17, p=0.001), and need for emergency surgery (odds ratio 3.65; 95% confidence interval: 1.59-8.38, p=0.002) were independent risk factors for early death. Follow-up ranged from 1 to 180 months (median 48 months). There were 4 lake deaths. Actuarial survival at 12 years was 92.6% +/- 2.8%. CONCLUSIONS: In Indian circumstances, mortality continues to be high in infants with total anomalous pulmonary venous connection. Severe pulmonary arterial hypertension appears to be the most important predictor of operative mortality. Severe malnutrition, delayed diagnosis and late referrals possibly contribute to the high mortality.