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Background: Subaortic membrane (SAM) is a form of fixed subaortic obstruction in which a fibrous membrane is located below the aortic valve. Aim: To determine the role of surgical treatment for patients with a discrete SAM. Patients and Methods: The hospital records of 45 patients (age range: 2–23 years; median 8 years) undergoing surgery for SAM between 1990 and 1998 at the All India Institute of Medical Sciences, New Delhi, India, were analysed. Preoperative echocardiographically calculated gradients across the left ventricular outflow tract ranged from 50 to 154 mmHg (mean: 86.5 ± 33.2 mmHg). Nine patients had trivial aortic regurgitation (AR), 10 had mild AR and five had moderate–severe AR. The left ventricular ejection fraction (LVEF) ranged from 20 to 68% (mean 48 ± 15%). Nineteen patients had significant left ventricular dysfunction (LVEF <50%). Transaortic resection of SAM was done in all patients along with excision of a wedge-shaped segment of septal muscle underlying the membrane. Results: There were no early or late postoperative deaths. On follow up (up to 113 months), only four patients had gradients >30 mmHg. LVEF improved to 45–70% (mean 58 ± 7.7%). AR reduced to mild in four patients and trivial in four patients, and did not progress further. Conclusion: Resection of SAM carries long-term benefits. Routine septal myectomy appears to be associated with a low risk of recurrence. (Heart, Lung and Circulation 2001; 10: 130–135). [ABSTRACT FROM AUTHOR]

Background: Encouraging results have been obtained from early univentricular repair. Our study was designed to assess the impact of young age (less than 2 years) on the outcome of univentricular repair. Patients and Methods: Between January 1992 and December 1998, 65 out of 311 patients undergoing univentricular repair at the All India Institute of Medical Sciences, New Delhi, were less than 2 years of age. We compared these 65 carefully selected patients (group 1) with the 246 patients who were more than 2 years of age (group 2). Since 1994, all patients of both groups had a fenestration of the intra-atrial baffle. Results: The early mortality rate was 9.2% in group 1 and 7.7% in group 2. The overall Fontan failure rate was 12.3% in group 1 and 12.2% in group 2. In group 1, a higher incidence of Fontan failure was noted in patients with suboptimal weight, non-tricuspid atresia morphology, non-fenestrated Fontan and those who did not comply with more than two of Choussat’s criteria, but the values were not statistically significant. Aortic cross-clamp time of more than 60 min was the only and highly significant predictor of Fontan failure (P < 0.01). The overall effusion rate was 24.05% in group 1 and 27.98% in group 2. In group 1, patients weighing less than 10 kg (P = 0.0007), without fenestration of the atrial baffle (P < 0.05) and with systemic ventricular dysfunction (P < 0.001), systemic ventricular end-diastolic pressure of more than 12 mmHg (P < 0.001), mean pulmonary artery pressure of more than 15 mmHg (P < 0.001) and aortic cross-clamp time of more than 60 min (P < 0.01), were all found to be significant risk factors of pleural effusion. Pulmonary artery distortion needing reconstruction did not increase the Fontan failure or effusion rates. Oxygen saturation ranged from 85 to 94% (mean 89%) in patients having a functioning fenestration at a mean follow-up period of 30 months. The actuarial survival at 84 months was 90 ± 0.04% in group 1 and 88 ± 0.02% in group 2. Conclusions: Our results suggest that carefully selected patients under 2 years of age are suitable candidates for one-stage univentricular repair and that survival is not significantly different from that of older patients. Routine fenestration of the intra-atrial baffle is an option available to ameliorate morbidity and obviate mortality. Non-compliance with more than two of Choussat’s criteria appears to be additive in unsatisfactory outcome. (Heart, Lung and Circulation 2001; 10: 3–13). [ABSTRACT FROM AUTHOR]