USE OF LEFT-VENTRICULAR EJECTION FRACTION OR WALL-MOTION SCORE INDEX IN PREDICTING ARRHYTHMIC DEATH IN PATIENTS FOLLOWING AN ACUTE MYOCARDIAL-INFARCTION

All-cause mortality and morbidity following an acute myocardial infarc tion (AMI) are correlated to LV systolic dysfunction. The correlation is closest with mortality and morbidity associated with congestive hea rt failure (CHF). Prediction of arrhythmic death in patients with AMI relies on the correlation between arrhythmic death and ''sudden unexpe cted death'' defined as death within 1 hour of onset of new symptoms. Assessment of late potentials, heart rate variability (HRV), T wave al ternans, arrhythmias seen on Holter monitoring or during exercise test ing electrophysiological testing, and baroreceptor assessment have all proven to be useful in the prediction of sudden death even when LV sy stolic function is known. In selected populations HRV is superior to L V systolic function assessment in predicting sudden death and/or arrhy thmic events, and may even predict ah-cause mortality with the same pr ecision. Comparisons of other methods with LV function assessment shou ld be interpreted with care because most methods have been evaluated i n subgroups of infarct patients with a low risk of death. Results from a large series of high risk patients with AMI (the TRAndolapril Cardi ac Evaluation study) have shown that even in patients with severe depr essed LV systolic function around one-third of the patients will die s uddenly. The current situation is that LV function appears to be the b est method of predicting death whereas other methods appear very promi sing for detecting arrhythmic death in more selected populations. The optimal method for selecting patients at high risk of arrhythmic death has not yet been developed, but a combination of LV function and anot her method, i.e., HRV, appears promising. This may ensure that the enr olled patients have an increased risk of death and that this risk will be due to arrhythmic events. Patients with LVEF of 10% or less can be excluded as they will most likely not die suddenly.