[The "arrhythmic pattern": a new method with prognostic significance in myocardial infarct].

OBJECTIVES

To establish a score or arrhythmic pattern for the prediction of long-term cardiac deaths on patients who have survived to the first acute myocardial infarction.

PATIENTS AND METHODS

We studied prospectively 200 patients that survived at a first myocardial infarction and in whom ambulatory ECG monitoring during 24 hours between days 7th and 18th (mean 12th) from the infarction was performed. The mean follow-up time was 51 +/- 18 months. The number and type of ventricular arrhythmias were analyzed and a score was measured, accordingly with Castellanos and Lown's classifications. An "arrhythmic pattern" or "total punctuation" was defined and compared among two groups: group 1 > 65 points and group 2 < 65 points.

RESULTS

The differential characteristics of both groups were: age (60 +/- 9 versus 56 +/- 10 years old; p = 0.004); hypertension (63% versus 29%; p < 0.001); clinic stage II-III (23% versus 11%; p = 0.02); echocardiographic ejection fraction (45 +/- 11% versus 50 +/- 10%; p = 0.04); positive exercise testing (73% versus 56%; p = 0.01); arrhythmias on the exercise test (15% versus 25%; p = 0.006). The long-term cardiac mortality was 25% versus 6% (p = 0.01), with an incidence of sudden death of 11% versus 3% (p < 0.05). Specificity, sensibility, positive predictive value and negative predictive value (reference cut point of 100) were 94, 65, 71 and 91%, respectively.

CONCLUSIONS

The use of a score of arrhythmic pattern may identify 2 groups of patients with different clinic profiles that probably justify a different long-term prognosis after a first acute myocardial infarction.