[Relationship between exercise induced ischemia and left ventricular dysfunction; simultaneous assessment of...

The purpose of this study was to evaluate the relationship between exercise induced ischemia and left ventricular dysfunction, ergometer exercise 99mTc-tetrofosmin myocardial scintigraphy was performed using one day protocol (exercise/rest). Subjects consisted of 68 patients without previous myocardial infarction; without coronary artery disease (CAD) (n = 36) and with CAD (n = 32). Perfusion and function images were evaluated simultaneously. Perfusion image was taken by single photon emission tomography (SPECT). Quantitative analysis was performed with normal data-base. The area of abnormal perfusion, less than normal lower limits, was named as extent score (ES). Left ventricular ejection fraction (LVEF) was measured by first-pass study. According to ES on stress image, 32 patients with CAD were divided into 3 groups; ES < 10% (n = 15), ES = 10-20% (n = 7) and ES > 20% (n = 10). LVEF at rest among 4 groups were not different. LVEF at peak exercise was 61.7+/ -5.3% in CAD (-), 59.0 +/- 5.8% in ES < 10%, 57.4 +/- 6.6% in ES = 10-20% and 47.4 +/- 10.5% in ES > 20%. LVEF in ES > 20% at peak exercise was lowest significantly. Thus, simultaneous perfusion and function images were evaluated for the relationship between exercise induced ischemia and left ventricular dysfunction. If extent score on stress image was more than 20% of left ventricle, significant left ventricular dysfunction was observed.