Isolated valvular pulmonic stenosis (PS) in association with tricuspid regurgitation and congestive heart failure (CHF) is rarely encountered after infancy, and there is very little information available regarding the application of pulmonary balloon valvotomy (PBV) for this subset of patients. Since 1985, 10 patients (5 males, 5 females; mean age: 12.4 +/- 7.5 years, range 4-25 years) underwent PBV for severe valvular PS with CHF in our institution. All patients had associated tricuspid regurgitation and cardiomegaly. Before PBV, the mean peak systolic gradient across the right ventricular outflow was 131 +/- 36 mmHg and the mean right atrial pressure was 14.4 +/- 5.4 mmHg. Specific modifications in the PBV technique included the sequential use of progressively larger balloon catheters and the use of an extra stiff guidewire to support the dilatation assembly. One patient underwent PBV via the right internal jugular vein. Problems encountered during PBV included hypotension and bradycardia (2 patients) and respiratory arrest, which was transient in one patient, and prolonged and eventually fatal in one patient. A successful outcome was achieved in 8 patients (4 of these required 2 PBV attempts) with a final residual gradient of 40 mmHg or less, mean 28 +/- 7; range: 21-38 mmHg) and complete resolution of CHF. One patient has had no significant change in gradients and awaits repeat dilatation. Patients with isolated severe valvular PS with TR and CHF represent a relatively high risk group for PBV. A successful outcome is, however, feasible if a carefully planned and cautious approach is used.