When time is precious--time lags as indicators of quality of care in acute myocardial infarction

Abstract

Intravenous thrombolytic therapy is known to reduce mortality in acute myocardial infarction. The effect is highly time dependent and is uncertain 12 hours or more after onset of major symptoms. In order to assess aspects of quality of care for the initial treatment of acute myocardial infarction, pre- and in-hospital time lags were recorded in four Norwegian hospitals for patients admitted to the intensive care unit with acute myocardial infarction and for patients who received thrombolytic therapy for acute ischemic coronary heart disease. Four hundred and forty-six patients were included, of whom 45% (199) received thrombolytic medication, 159 after the initial assessment and 40 after observation and reassessment. All patients receiving thrombolytic therapy had a history of pain, and 94% (187) had significant ECG-changes. Median pre-hospital time was 240 (1. and 3. quartil 120, 519) min for the total sample and 155 (91, 280) min for those who received thrombolytic medication after the primary assessment. Median in-hospital time before thrombolysis was 55 (35, 75) min for the latter group, and 177 (111, 335) for those who were observed and reassessed. We conclude that there is considerable potential for reducing the time lag for initiation of thrombolytic medication in acute myocardial infarction. Audits, written guidelines and standards are necessary to reduce in-hospital time.