Apexcardiograms and hemodynamic studies were performed in 32 postmyocardial infarction patients. Group 1 patients (5) had markedly elevated left ventricular end diastolic (LVED) pressures but normal LVED volumes; apexcardiograms included tall A waves (31 percent of the E to O points), prolonged A-wave durations of 134 msec or greater, short rapid filling wave durations (55 msec) and slow-filling ... [Show full abstract] waves replaced by plateaus in three patients. Group 2 patients (10) had markedly elevated LVED pressures and elevated LVED volumes, and had similar apexcardiographic findings: A-wave heights had a mean of 23.4 percent of E to O points, A-wave durations were 113 msec or more, rapid filling wave (RFW) durations were 93 msec and diastolic plateaus occurred in five patients. Group 3 patients (11) had intermediate hemodynamic findings and the apexcardiograms were varied; three patients with mild congestive heart failure (CHF) had apexcardiograms similar to Group 1 and five without CHF had apexcardiograms similar to those in Group 4. Group 4 patients (6) had normal hemodynamic findings; the mean A-wave height was 6 percent of the E to O point height, A-wave durations 90 msec or less RFW durations were 117.5 msec or more and the slow-filling wave duration (SFW) was normal in the configuration. Fourteen of 15 patients in Groups 1 and 2 developed CHF and six died on follow-up. Group 4 patients showed no evidence of CHF on follow-up and there were no deaths. Group differences were significantly different for A-wave height and duration, and for RFW duration at 0.05 or 0.01.Tall prolonged A waves and short RFWs were associated with poor left ventricular (LV) compliance and dysfunction, and diastolic plateau immediately following the RFW when present were confirmatory. Thus, the apexcardiogram is a reproducible useful noninvasive tool for clinical assessment, and predicting prognosis in postmyocardial infarction patients.