Prognostic significance of normal myocardial perfusion imaging among blacks and hispanics in an inner-city population

Abstract

Background: Previous studies have shown that the risk of death/MI at 1 year is less than 1% in patients with normal stress myocardial perfusion imaging. However, the racial distribution of patients enrolled in these studies is not known or very few Blacks and Hispanics were included. Hence, the prognostic value of normal stress perfusion imaging in Blacks and Hispanic patients is not well established. Our objective was to determine the incidence of all cause mortality in Blacks and Hispanics with normal myocardial stress perfusion scan and EF. Methods and Results: Retrospective review of 657 patients who had normal SPECT Tc99m sestamibi stress perfusion study utilizing attenuation and scatter correction, with gated SPECT EF ≥45 in year 2000. Blacks 34%, Hispanics 55%. All cause mortality from Social Security Death Index was 22 (3.3%) over at least 36 months period, thus an annual mortality rate of approximately 1.1%. Study population was divided in two groups those alive and those dead. Analysis showed that following characteristics were predictor for increased mortality, older age, diabetes mellitus, High resting heart rate, resting EKG abnormalities, low end point systolic and diastolic pressure. There was no significant difference amongst the two groups in gender, smoking h/o hypertension, resting systolic or diastolic blood pressure, EF by gated SPECT and transient Ischemic dilatation. Characters Alive (N = 635) Dead (N = 22) P value Age 58.3 ± 11.9 65.9 ± 12.8 0.003 Diabetes Mellitus 27% 77% 0.0000003 Resting EKG abn 44% 82% 0.0004 Resting HR 70 ± 14 82 ± 18 0.0004 Endpoint SBP 159 ± 36 137 ± 41 0.007 Endpoint DBP 75 ± 12 67 ± 11 0.002 Conclusions: This study is first of its kind study in an inner city population. The overall mortality in Black and Hispanic patients with normal stress perfusion study with EF≥45 is very low and similar to other Non-Black and Non-Hispanic population.