Research Abstract |
In order to make remote analog and digital recordings of blood pressure, coronary blood flow, diameters of large epicardial coronary artery and of left ventricle and others from unanesthetized and unrestrained dogs for the study on hemodynamic effects of antianginal drugs, we developed a miniature pressure telemeter, blood flow telemeter based on Doppler principle and a transit time dimension telemeter and their radio-receiver and demodulating, signals and deta processing systems. In application, we examined effects of some anti-anginal drugs on diameters of epicardial large coronary artery and left ventricle, LVP, LVdp/dt, LVEDP, coronary blood flow, blood pressure, heart rate and ECG. Sublingual nitroglycerin 5 microgram/kg effectively increased left circumflex coronary diameter, the effect lasted 5-8 minutes. However, coronary blood flow, heart rate, blood pressure, left ventricular diameter, LVEDP and LVdp /dt were not significantly changed. With increasing dose up to 25 microgram/kg, these effects have not changed basically. It is concluded that the prime therapeutic action of nitroglycerin in angina pectoris is related to dilate large coronary arteries.
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