Ramipril and left ventricular diastolic function in stable patients with pulmonary regurgitation after repair of tetralogy of Fallot

Measures of left ventricular (LV) systolic and diastolic function are known predictors of mortality after repair of tetralogy of Fallot. We aimed to characterise LV reverse remodelling achievable with ramipril therapy. A blinded post-hoc analysis of baseline and 6-month follow-up echocardiograms from the APPROPRIATE (ISRCTN: 97515585) randomised double-blinded placebo-controlled trial of ramipril therapy was performed in 64 patients: 32 in ramipril and 32 in placebo group. Tissue Doppler systolic and diastolic myocardial velocities, mitral inflow velocities and time intervals were measured. Left atrial area and left atrial emptying fraction were calculated. There was significant increase in long axis shortening mean (standard deviation); MAPSE [1.9 (4.2) mm vs −0.2 (3.7) mm; p = 0.030], peak lateral systolic velocity; S′ lateral [1.0 (2.0) cm/s vs −0.3 (2.2) cm/s; p = 0.025], peak lateral early diastolic velocity; E′ lateral [0.57 (2.4) cm/s vs −3.3 (3.9) cm/s; p < 0.001], transmitral to lateral mitral annular early diastolic velocity ratio; E/E′ lateral [−0.7 (1.9) vs 1.5 (1.9); p < 0.001] over the study period in the ramipril compared to the placebo group. Significantly higher measurements were observed in the ramipril arm of the subgroup of patients with right ventricular restrictive physiology in terms of peak late diastolic velocity; A [5.9 (13.5) cm/s vs −5.8 (12.5) cm/s; p = 0.041] and early to late diastolic transmitral velocity ratio; E/A [−0.18 (0.42) vs 0.23 (0.48); p = 0.037]. Six months' ramipril treatment appears to limit progression of both diastolic and systolic LV function in adults late after tetralogy of Fallot repair. With increased appreciation that even subtle LV disease predicts tetralogy of Fallot outcomes, further clinical trials of drug therapies are justified.