Exercise Brachiocephalic Artery Doppler Echocardiography: A new Method for Assessment of Left Ventricular Function
川添 康郎1, 鳥居 博行2, 田原 稔2, 有馬 新一3, 田中 弘允3
Yasurou KAWAZOE1, Hiroyuki TORII2, Minoru TAHARA2, Shin-ichi ARIMA3, Hiromitsu TANAKA3
1垂水中央病院循環器内科, 2鹿児島市医師会病院循環器内科, 3鹿児島大学医学部第一内科
1Department of Cardiac Medicine, Tarumizu Central Hospital, 2Department of Cardiac Medicine, Kagoshima Municipal Medical Association Hospital, 3The First Department of Internal Medicine, Kagoshima University
Exercise Doppler echocardiography, Peak flow velocity in the brachiocephalic artery, Left ventricular ejection fraction, Radionuclide angiography
We performed Doppler flow studies by the right minor supraclavicular approach to assess left ventricular performance during exercise. To determine the usefulness of this approach, three patients with chest pain syndrome and 14 patients with documented coronary artery disease (mean age 63±9 years) were subjected to simultaneous Doppler echocardiography by this approach and radionuclide angiography at rest and during supine bicycle exercise test at the load of 50 watts. Exercise Doppler study was performed using 5 MHz continuous wave Doppler single probe after the determination of the vessel using color-guided continuous Doppler at rest. The vessels detected by the approach were the brachiocephalic artery in 15 patients and the ascending aorta in 2. Exercise-induced changes in Doppler peak flow velocity correlated well (r=0.92) with changes in ejection fraction as seen from radionuclide angiography. In 6 patients with coronary artery disease, changes in ejection fraction were less than 5%. The velocity fell from baseline in 4 out of 6 patients and changed little in 2. In the remainder, both the velocity and the ejection fraction increased normally. Moreover, fifteen healthy male subjects (mean age 33±5 years) were subjected to Doppler echocardiography from the right minor supraclavicular notch during treadmill exercise testing. The study was repeated after 30 minutes by Doppler monitoring from the suprasternal notch. Both peak brachiocephalic arteric flow velocities and peak aortic flow velocities progressively increased during exercise. There was no significance in both velocities at each stage of exercise. We conclude that Doppler monitoring of the brachiocephalic artery, which is technically feasible, can be used to evaluate left ventricular performance during exercise.