Spectrum of congestive heart failure late after aortic valve or mitral replacement: differentiation of valvular versus myocardial cause by radionuclide ventriculogram-ejection fraction.

Heart failure (CHF) appearing late after aortic (AV) or mitral valve (MV) replacement (R) may be due to mechanical factors such as prosthetic or native dysfunction, or due to myocardial disease. We studied 41 patients who developed CHF late (6 weeks to 11 years) after AVR or MVR with gated blood pool scan (RNV) to analyze the spectrum of ejection fraction (EF) and its clinical correlates. Of the 17 patients who developed CHF after AVR, 10 had RNV EF greater than 0.5 (all of whom had severe valve or prosthetic dysfunction as the primary cause of CHF) and seven had EF less than 0.5 (five with severe myocardial disease and two with prosthetic dysfunction). Of the 24 with CHF after MVR, 13 had RNV EF greater than 0.5. In contrast to post-AVR patients, only 8 of the 13 patients had mechanical causes of CHF (seven prosthetic dysfunction and one constrictive pericarditis). Of the 11 patients after MVR with EF less than 0.5, nine had severe myocardial disease and two had prosthetic dysfunction. Thus (1) reduced EF in patients and CHF-after AVR or MVR suggests myocardial disease as the basis for CHF, and (2) normal EF implies a mechanical cause of CHF after AVR but may be associated with either myocardial or mechanical factors after MVR.