Objectives. Our aim was to determine mechanisms underlying abnormalities of right ventricular (RV) diastolic function seen in heart failure. Background. It is not clear whether these right-sided abnormalities are due to primary RV disease or are secondary to restrictive physiology on the left side of the heart. The latter regresses with angiotensin-converting enzyme inhibition (ACE-I). Methods. Transthoracic echo-Doppler measurements of left- and right- ventricular function in 17 patients with systolic left ventricular (LV) disease and restrictive filling before and 3 weeks after the institution of ACE-I were compared with those in 21 controls. Results. Before ACE-I, LV filling was restrictive, with isovolumic relaxation time short and transmitral E wave acceleration and deceleration rates increased (p < 0.001). Right ventricular long axis amplitude and rates of change were all reduced (p < 0.001), the onset of transtricuspid Doppler was delayed by 160 ms after the pulmonary second sound versus 40 ms in normals (p < 0.001) and overall RV filling time reduced to 59% of total diastole. Right ventricular relaxation was very incoordinate and peak E wave velocity was reduced. Peak RV to right atrial (RA) pressure drop, estimated from tricuspid regurgitation, was 45 ± 6 mm Hg, and peak pulmonary stroke distance was 40% lower than normal (p < 0.001). With ACE-I, LV isovolumic relaxation time lengthened, E wave acceleration and deceleration rates decreased and RV to RA pressure drop fell to 30 ± 5 mm Hg (p < 0.001) versus pre-ACE-I. Right ventricular long axis dynamics did not change, but tricuspid flow started 85 ms earlier to occupy 85% of total diastole; E wave amplitude increased but acceleration and deceleration rates were unaltered. Values of long axis systolic and diastolic measurements did not change. Peak pulmonary artery velocity increased (p < 0.01). Conclusions. Abnormalities of RV filling in patients with heart failure normalize with ACE-I as restrictive filling regresses on the left. This was not due to altered right ventricular relaxation or to a fall in pulmonary artery pressure or tricuspid pressure gradient, but appears to reflect direct ventricular interaction during early diastole.
Henein, M. Y., O’Sullivan, C. A., Coats, A. J. S., & Gibson, D. G. (1998). Angiotensin-converting enzyme (ACE) inhibitors revert abnormal right ventricular filling in patients with restrictive left ventricular disease. Journal of the American College of Cardiology, 32(5), 1187–1193. https://doi.org/10.1016/S0735-1097(98)00412-4