Determinants of immediate and follow-up results of pulmonary balloon valvuloplasty.

The data of 93 patients (age 11.4 +/- 9.4 years, range 8 months-56 years) who underwent pulmonary balloon valvuloplasty (PBV) for valvular pulmonic stenosis (PS) in our institution are reviewed. The patients were classified into three groups: Group I (34 patients) had a right ventricular (RV) to aortic systolic pressure ratio of < 1, Group II (39 patients) had suprasystemic RV systolic pressures, and Group III (20 patients) included patients with elevated mean right atrial (RA) pressures irrespective of the RV systolic pressures. The percentage drop in immediate postdilatation peak systolic gradients (PSG) and the follow-up PSG were similar in the three groups and were not influenced by any predilatation patient characteristics. A balloon-annulus ratio < 1 predicted a poorer follow-up outcome. Nine patients, eight of Group III and one of Group II, experienced difficult procedures requiring sequential use of progressively larger balloon catheters. Eleven patients, six of Group II and five of Group III, experienced procedure-related events (hypotension, bradycardia/asystole, hypoxia, apnea, tachyarrhythmias, and seizures) and one patient (Group II) died. Although changes in immediate and follow-up gradients after PBV are not influenced by the severity of PS, difficult procedures and procedure-related events are particularly common in patients with severe PS and elevated RA pressures. A cautious and planned approach is therefore indicated in these patients.