Preoperative Thresholds for Pulmonary Valve Replacement in Patients With Corrected Tetralogy of Fallot Using Cardiovascular Magnetic Resonance

Abstract

Background-To facilitate the optimal timing of pulmonary valve replacement, we analyzed preoperative thresholds of right ventricular (RV) volumes above which no decrease or normalization of RV size takes place after surgery. Methods and Results-Between 1993 and 2006, 71 adult patients with corrected tetralogy of Fallot underwent pulmonary valve replacement in a nationwide, prospective follow-up study. Patients were evaluated with cardiovascular magnetic resonance both preoperatively and postoperatively. Changes in RV volumes were expressed as relative change from baseline. RV volumes decreased with a mean of 28%. RV ejection fraction did not change significantly after surgery (from 42Ϯ10% to 43Ϯ10%; Pϭ0.34). Concomitant RV outflow tract reduction resulted in a 25% larger decrease of RV volumes. After correction for surgical RV outflow tract reduction, higher preoperative RV volumes (mL/m 2 ) were independently associated with a larger decrease of RV volumes (RV end-diastolic volume: ␤ϭ0.41; PϽ0.001). Receiver operating characteristic analysis revealed a cutoff value of 160 mL/m 2 for normalization of RV end-diastolic volume or 82 mL/m 2 for RV end-systolic volume. Conclusions-Overall, we could not find a threshold above which RV volumes did not decrease after surgery. Preoperative RV volumes were independently associated with RV remodeling and also when corrected for a surgical reduction of the RV outflow tract. However, normalization could be achieved when preoperative RV end-diastolic volume was Ͻ160 mL/m 2 or RV end-systolic volume was Ͻ82 mL/m 2 . (Circulation. 2007;116:545-551.)

Analysis of right ventricle function with strain imaging before and after pulmonary valve replacement

“…Knirsch et al [6] determined pre-replacement RV end-diastolic volume as 201 ± 47 mL/m 2 , and RVEF as 45 ± 6%, while those values were found as 109 ± 15% and 42 ± 8%, 6 months after replacement. Although the studies in the literature found a statistically significant reduction in end-diastolic volume after replacement, they did not find any change in ejection fraction which reflected global systolic function [2,5,7,8]. In our study, although we found highly significant differences in end-diastolic and end-systolic volumes after replacement, we did not find any significant difference for ejection fraction (Table 1).…”

Timing and Technique of Pulmonary Valve Replacement in the Patient With Tetralogy of Fallot

“…Prolonged QRS duration has been associated with sudden death and ventricular tachycardia. [10][11][12][13] In general, PVR results in a modest reduction of QRS duration. 14 In a study by Van Huysduynen et al, 15 26 patients underwent PVR and the average QRS duration decreased from 151 Ϯ 30 ms to 144 Ϯ 29 ms early (6 to 12 months).…”

“…These findings were subsequently confirmed by others. 12,14,23 In addition to volumes, CMR can also provide additional data on ejection fraction of both the RV and LV. In a cross-sectional study, Knauth et al 24 examined 88 patients with repaired TOF by CMR.…”

Immediate and long-term outcomes of percutaneous transcatheter pulmonary valve implantation

“…The general indications for pulmonary valve replacement are well defined [1,2] and rely on right ventricular (RV) enlargement and functional compromise, along with pulmonary artery stenosis and/or regurgitation. Both are preferentially presented on magnetic resonance imaging [3]. The number of patients undergoing transcatheter pulmonary valve implantation has been steadily increasing.…”