Effects oftheAngiotensin Converting Enzyme Inhibitor Enalapril on theLong-term Progression ofLeftVentricular Dysfunction inPatients WithHeartFailure

before andafter randomization toenalapril (2.5-20 mg/day) or placebo. At1 year,there were significant treatment differences inLV end-diastolic volume(EDV;p<0.01), end-systolic volume(ESV;p<0.005), andEF (p<0.05). Theseeffects resulted fromincreases inEDV (mean±+SD, 136±27to151+±38 ml/m2) andESV (103±24 to116±24ml/m2) intheplacebo groupanddecreases inEDV (140±44 to127±37ml/m2) and ESV(106±42 to93+±37 ml/m2) intheenalapril group.MeanLVEFincreased inenalapril patients from 0.25±0.07 to0.29±0.08 (p<0.01). Therewas a significant treatment difference inLV end-diastolic pressureat1year(p<0.05), withchanges paralleling those ofEDV.Thetimeconstant ofLVrelaxation changed onlyintheplacebo group(p<0.01 versusenalapril), increasing from59.2±8.0 to67.8+7.2 msec. Serial radionuclide studies overaperiod of33monthsshowedincreases inLVvolumes only intheplacebo group.Twoweeksafter withdrawal ofenalapril, EDVandESVincreased tobaseline levels butnottothe higher levels observed withplacebo. Conclusions. Inpatients withheartfailure andreduced LVEF,chronic ACE inhibition withenalapril prevents progressive LVdilatation andsystolic dysfunction (increased ESV).Theseeffects probably result fromacombination ofaltered remodeling andsustained reduction inpreload andafterload. (Circulation 1992;86:431-438)