[Compared predictive value of clinical variables and 24-hour Holter monitoring on survival 1 year and 4 years after myocardial infarction].
The purpose of this study was to determine precisely which additional information on survival at 1 year and 4 years was provided by an ambulatory 24-hour ECG recording performed 3 weeks after myocardial infarction (MI), compared to clinical data. The study was conducted in 107 consecutive patients under 75 years of age who had had MI and were followed up for a mean period of 4 years and 9 months. The clinical variables most closely associated with mortality at both 1 year and 4 years were those which reflected the severity of myocardial damage and left ventricular dysfunction before or during hospitalization, viz.: a history of MI or heart failure (HF), HF in the acute phase, and digitalis-diuretic treatment on discharge. At 4 years a multivariate analysis yielded 3 separate clinical variables which enabled cardiac mortality to be predicted: history of MI (p less than 0.001), presence of HF in the acute phase (p less than 0.001) and history of hypertension (p less than 0.02). Ventricular arrhythmias also were closely associated with mortality, but only during the first year, the 2 most discriminant factors being a mean hourly frequency of ventricular ectopic beats (VEB) greater than 10, and the presence of successive VEB (doublet or burst of ventricular tachycardia). The positive predictive values (PPV) of clinical and ambulatory ECG recording variables taken separately for mortality at 1 year were fairly similar (about one-third) as regards HF in the acute phase, history of MI, successive VEB and mean VEB frequency greater than 10/h, the corresponding risk ratios being 23.9, 13.7, 11.6 and 9.4 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)