高田 博之¹, 増田 善昭², 稲垣 義明², 澤田 準³

Hiroyuki TAKATA¹, Yoshiaki MASUDA², Yoshiaki INAGAKI², Hitoshi SAWADA³

¹(財)東京都保健医療公社　東部地域病院循環器科, ²千葉大学医学部第3内科, ³心臓血管研究所

¹Department of Cardiology, Tobu Regional Hospital, ²The Third Department of Internal Medicine, Chiba University, ³The Cardiovascular Institute

キーワード : Exercise echocardiography, Left ventricular diastolic function, Pulsed Doppler echocardiography

Exercise 2-dimensional echocardiography has developed into a clinically useful tool in the assessment of patients with suspected coronary artery disease. The specificity of exercise 2-dimensional echocardiography was reported to be high. However, its sensitivity was not adequate. As exercise induced mypcardial ischemia produces both systolic and diastolic dysfunction, assessment of the changes in left ventricular diastolic function after exercise might be used to detect exercise induced myocardial ischemia. To investigate the utility of the Doppler assessment of the left ventricular diastolic function with exercise, and to evaluate the possibility that the combination of exercise 2-dimensional echocardiography and pulsed Doppler echocardiography could improve diagnostic accuracy, 28 patients with coronary artery disease were evaluated using exercise pulsed Doppler echocardiography. Then these patients were compared with 22 healthy subjects (study group 1). Thereafter, the accuracy of the criteria induced by the analysis of study group 1 was assessed prospectively in 52 patients with suspected coronary artery disease (study group 2). Two-dimensional echocardiograms were recorded before and immediately after the treadmill exercise test. Pulsed Doppler echocardiograms of transmitral blood flow were recorded before and 15 minutes after exercise when the heart rate returned to normal.
In study group 1, the peak velocity in the early diastolic filling phase (E) in patients with single vessel disease decreased from 45±12 cm/s to 35±9 cm/s (pThe subjects in study group 2 were evaluated by a combination of exercise 2-dimensional and pulsed Doppler echocardiography. For the overall recognition of coronary artery disease, fortyseven patients from this group (90%) were classified accurately. To discriminate between cases of single vessel disease and cases of multivessel disease, it was necessary to evaluate the pulsed Doppler indices (ΔA/E, IRT after exercise).Thus, by adding pulsed Doppler echocardiography to 2-dimensional echocardiography, the diagnostic accuracy of exercise echocardiography could be much improved.