Risk stratification after acute myocardial infarction by Doppler stroke distance measurement

Objective-To establish the value of Doppler stroke distance measurement as a predictor of mortality risk following acute myocardial infarction. Design-Follow up study. Setting-Coronary care unit of a teaching and district general hospital. Subjects-378 patients (mean age 61 years) with acute myocardial infarction followed up for a mean of five years (range 2-7 years); 299 (79%) patients received thrombolysis. Main outcome measures-Stroke distance (the systolic velocity integral of bl ood flow in the aortic arch (percentage of age predicted normal value)); pr esence or absence of left ventricular failure on the admission chest radiog raph; the codified admission EGG; death during follow up. Results-Mean (SD) stroke distance was 81 (19)% and five year survival 76%. For patients with stroke distance >100% (n = 60), 82-100% (n = 134), 63-81% (n = 122), and < 63% (n = 62), the one month mortality rates were 0%, 1.5% , 4%, and 18%, respectively; the corresponding estimates for mortality at f ive years were 17%, 19%, 24%, and 43%. Survival was independently related t o age (p < 0.0001), stroke distance (p < 0.0001), and chest radiograph appe arance (p = 0.002), but not to ECG codes (p = 0.31) or receipt of thromboly sis (p = 0.60). The areas under receiver operator characteristic plots for stroke distance measurements were 82%, 76%, 71%, and 65% for deaths within one month, six months, one year, and two years, respectively. Conclusions-The bedside measurement of stroke distance stratifies mortality risk after acute myocardial infarction. The predictive ability of this sim ple measure of left ventricular systolic function compares well with publis hed accounts of the more complex measurement of ejection fraction.