THE PREDICTIVE VALUE OF ADMISSION HEART-RATE ON MORTALITY IN PATIENTSWITH ACUTE MYOCARDIAL-INFARCTION

The purpose of this study was to assess the predictive value of admiss ion heart rate (HR) for in-hospital and 1 year post-discharge mortalit y in a large cohort of patients hospitalized for acute myocardial infa rction (MI). Data were derived from the SPRINT-2 secondary prevention study population, and included 1044 patients (aged 50-79), hospitalize d in 14 coronary care units in Israel with acute MI in the years 1985- 1986, before the beginning of thrombolytic therapy in acute MI. Demogr aphic, historical and medical data were collected for each patient. Al l deaths during initial hospitalization and 1 year post-discharge were recorded. In-hospital mortality was 5.2% for 294 patients with HR <70 beats/min, 9.5% for 532 patients with HR 70-89 beats/min, and 15.1% f or 323 patients with HR greater than or equal to 90 beats/min (p < 0.0 1). One year post-discharge mortality was 4.3% for patients with HR <7 0 beats/min, 8.7% for patients with HR 70-80 beats/min and 11.8% for p atients with HR greater than or equal to 90 beats/min (p < 0.01). An i ncreasing trend of mortality with higher HR was confined to patients w ith mild CHF (p = 0.02) and likely to patients with absent CHF (p = 0. 06), but this post hoc observation requires confirmation in larger gro ups. The combination of high admission HR (greater than or equal to 90 beats/min) and a systolic blood pressure <120 mmHg was a powerful pre dictor of in-hospital mortality. Multivariate analysis showed that adm ission HR was an independent risk factor for in-hospital and 1 year po st-discharge mortality. An increase in HR of 15 beats/min was associat ed with average estimated increases of in-hospital and 1 year post-dis charge mortality of 36 and 45%, respectively. This study demonstrates that elevated admission HR is an independent predictor of in-hospital and subsequent mortality in patients with acute MI. Admission HR is as sociated with mortality in patients with mild CHF and likely also in c ounterparts without CHF. The association is clearly seen in men and is of similar magnitude, although not statistically significant for 1-ye ar mortality, in women.