Delayed improvement of right ventricular diastolic function and regression of right ventricular mass after percutaneous pulmonary valve implantation in patients with congenital heart disease. 
Percutaneous pulmonary valve implantation (PPVI) has been introduced as therapy for right ventricular (RV) to pulmonary artery conduit dysfunction in patients with congenital heart disease.  It has been shown that RV systolic function improved early after PPVI.  The effects of PPVI on RV diastolic function and RV hypertrophy have not yet been studied.  The objective of this study is to assess early and late changes in systolic and diastolic RV function and RV mass after PPVI.  Fourteen patients underwent PPVI (7 male, median age 15 years).  Cardiac magnetic resonance imaging was performed before and at 2 time points after PPVI (at 1 and 16 months).  Right ventricular volume and systolic and diastolic function as well as RV mass were assessed.  At 1 and 16 months after PPVI, the RV mass decreased from 28.6 +/- 2.1 to 25.6 +/- 2.2 g/m(2) (P = .03) and to 22.3 +/- 2.1 g/m(2) (P = .002).  E/A volume ratio increased from 1.91 +/- 0.4 to 2.6 +/- 0.4 (not significant [NS]) and to 3.3 +/- 0.4 (P = .01).  E/A peak flow ratio increased from 1.34 +/- 0.14 to 1.48 +/- 0.16 (NS) and to 1.73 +/- 0.14 (P = .04).  E-wave deceleration time increased from 142 +/- 25 to 160 +/- 27 milliseconds (NS) and to 211 +/- 26 milliseconds (P = .007).  At 1 month, RV end-diastolic volume decreased from 124 +/- 8 to 113 +/- 8 mL (P = .01) and RV ejection fraction increased from 36% +/- 2% to 46% +/- 2% (P = .001) without further improvement at 16 months.  After PPVI, in contrast to rapid improvement of RV systolic function, the improvement of RV diastolic function is delayed.  The reduction of RV mass appears to be the underlying mechanism for improvement of RV diastolic function.  Long follow-up for patients with PPVI is recommended.