BALLOON PULMONARY VALVOPLASTY - FACTORS DETERMINING SHORT-TERM AND LONG-TERM RESULTS

Balloon pulmonary valvoplasty was performed in 139 patients (age 2-44 years) with pulmonary valve stenosis. The right ventricular peak systo lic pressure decreased from 137.1 +/- 46.8 mmHg to 76 +/- 51.3 mmHg (P < 0.001) and the right ventricle to pulmonary artery peak systolic gr adient decreased from 116.3 +/- 49 mmHg to 54.4 +/- 51.9 mmHg (P < 0.0 01). There was no significant change in systemic artery systolic press ure. The right ventricular peak systolic pressure to systemic artery s ystolic pressure ratio decreased from 1.13 +/- 0.41 to 0.63 +/- 0.42 ( P < 0.001). Patients with incomplete immediate relief of obstruction ( right ventricle to pulmonary artery peak systolic gradient > 35 mmHg) had higher pre-dilatation right ventricular peak systolic pressure (16 1.1 +/- 45.3 mmHg vs. 93.9 +/- 38.8 mmHg, P < 0.001) and higher right ventricular peak systolic pressure to systemic artery systolic pressur e ratio (1.31 +/- 0.42 vs 0.98 +/- 0.33, P < 0.001) pre-dilatation and were older (17.2 +/- 8.6 years vs. 12.8 +/- 9.7 years, P < 0.01). The residual right ventricle to pulmonary artery peak systolic gradients in the majority of patients were infundibular, which regressed at foll ow up even in patients who did not receive long-term oral beta blocker s. Follow up catheterisation in 79 patients after 13 +/- 8.7 months sh owed a further fall in right ventricular peak systolic-pressure (P < 0 .001) and right ventricle-to-pulmonary artery peak systolic gradient ( P < 0.001). As assessed by follow up catheterisation data, 81% had no significant residual right ventricle-to-pulmonary artery peak systolic gradient while four patients showed significant increase in gradients compared to values obtained immediately after balloon pulmonary valvo plasty. A higher postdilatation right ventricular peak systolic pressu re to systemic artery systolic pressure ratio was predictive of an uns atisfactory late result. Among patients with a dysplastic pulmonary va lve only those with a mild degree of dysplasia improved. In conclusion balloon pulmonary valvoplasty is safe and provides long-term relief o f obstruction in the majority of patients with pulmonary valve stenosi s. Older patients with more severe stenosis are more likely to have re sidual infundibular gradients. Infundibular gradients regress at follo wup with or without beta blockers.