Prognostic value of left ventricular diastolic function and association with heart rate variability after a first acute myocardial infarction

Objective-To study the prognostic value of left ventricular (LV) diastolic function and its relation with autonomic balance expressed by heart rate va riability (HRV) in patients after a first acute myocardial infarction. Design-The study population consisted of 64 consecutive patients with first acute myocardial infarction and 31 control subjects. Long and short term H RV indices were evaluated by 24 hour Holter monitoring, and LV systolic and diastolic function were assessed by two dimensional and Doppler echocardio graphy before discharge. Patients were divided into two groups: those with restrictive IV filling characteristics (deceleration time less than or equa l to 140 Ins) and those with non-restrictive LV filling characteristics (de celeration time > 140 ms). Results-Both long and short term HRV indices were significantly reduced in patients with restrictive LV filling compared with the non-restrictive grou p and control subjects. Mitral deceleration time and isovolumetric relaxati on time correlated weakly but significantly with all indices of HRV whereas ejection fraction correlated weakly, vith the long term HRV indices. The m ean follow up time was 14.9 (8.7) months. Multivariate analysis showed that mitral deceleration time (chi (2) = 6.4, p < 0.001) and ejection fraction less than or equal to 40% (chi (2) = 4.4, p < 0.05) were independent predic tors of cardiac death, and readmission to hospital with congestive heart fa ilure. Conclusions-A restrictive IV filling pattern was found to be the strongest predictor of adverse outcome independent of HRV and ejection fraction durin g follow up after a first acute myocardial infarction. Patients with restri ctive IV filling characteristics had more reduced HRV than those with non-r estrictive diastolic filling.