Right Ventricular Function after Pulmonary Valve Replacement in Patients with Tetralogy of Fallot

Abstract

To assess the time course of right ventricular (RV) function improvement after pulmonary valve replacement (PVR) in patients 25.2 years +/- 7.0 after repair of tetralogy of Fallot. The medical ethics committee approved this study, and informed consent was obtained. Cardiac magnetic resonance (MR) imaging was performed before, 7 months after, and 19 months after PVR in 25 consecutive patients with tetralogy of Fallot with a 1.5-T MR imager. RV function was assessed with gradient-echo sequences in the short-axis plane. Pulmonary flow was assessed with a velocity-encoded phase-contrast sequence. Paired t test was used to evaluate follow-up data. Independent samples t test was used to assess differences based on the presence of recurrent pulmonary regurgitation (PR). Mean indexed RV end-diastolic volume decreased from 166.9 mL/m(2) +/- 41.3 before PVR to 113.5 mL/m(2)+/- 35.7 (P < .001) at 7-month follow-up and 111.7 mL/m(2)+/- 41.1 (P = .46) at 19-month follow-up. The RV ejection fraction was corrected for PR and improved from 25.0% +/- 7.7 before surgery to 44.1% +/- 11.9 (P < .001) and 45.2% +/- 11.1 (P = .39), at 7- and 19-month follow-up, respectively. Recurrent PR after PVR was found in 11 patients; 14 patients did not have recurrent PR. Total reduction of indexed RV end-diastolic volume at 19 months follow-up was more prominent in patients who did not have recurrent PR than in patients who did have recurrent PR (P < .05). Furthermore, improvement of RV ejection fraction corrected for regurgitation was more marked in patients who did not have recurrent PR than in patients who did have recurrent PR (P < .05). In patients with tetralogy of Fallot, RV function improves rapidly after PVR and is sustained at 19-month follow-up in most patients; however, recurrence of PR after PVR appears to reduce recovery of RV systolic function.