Effctss of coronary blood flow on intracoronary temperature *
The purpose of this study was to assess whether coronary flow has any effect on intracoronary temperature. Previous studies have shown the coronary arterial wall temperature to be elevated in cases with acute myocardial infarction or unstable angina while the temperature was not elevated in case with stable angina. Recently, a combined pressure/temperature sensor-mounted guidewire (combi-wire) which allows for the measurement of temperature differences within the coronary arteries was developed. In seven dogs under general anesthesia, the combi-wire was placed in the left anterior descending coronary artery (LAD). Then the LAD was occluded in its proximal portion by an ordinary percutaneous transluminal coronary angioplasty (PTCA) balloon or a perfusion balloon, and intracoronary temperature was measured in the distal LAD. A significant increase in temperature was demonstrated soon after coronary occlusion during balloon inflation (0.01ｱ0.02ｰC VS. 0.23ｱ 0.04ｰC ; p<0.0001) , but it was quickly normalized once the balloon occlusion was terminated (0.01 ｱ 0.03"C). However, no significant temperature change was observed during balloon inflation and after balloon deflation using the perfusion balloon (0.01 ｱ 0.02ｰC VS. 0.02 ｱ 0.03ｰC, p = NS). Intracoronary temperature elevates during coronary artery occlusion, and coronary blood flow may have an effect on coronary artery temperature regulation. This result should be taken into account in the assessment of coronary atheroma plaque temperature. (Accepted on October 27, 2003)
