SUMMARY We performed cross-sectional echocardiograms at rest, during supine bicycle exercise, and after sublingual nitroglycerin administration in 28 patients suspected of having ischemic heart disease. Technically adequate exercise cross-sectional echocardiograms were obtained in 20 patients (71%). Ten patients had new areas of reversible segmental dysynergy, and all 10 had significant stenoses of coronary arteries supplying areas of the heart corresponding to the location of reversible dysynergy. Six of these 10 patients also underwent exercise thallium-201 perfusion scanning, and all six had reversible perfusion defects in the area that demonstrated reversible dysynergy on exercise cross-sectional echocardiography. At least two of the remaining 10 patients who did not have reversible segmental dysynergy on exercise cross-sectional echocardiography probably experienced myocardial ischemia that we did not detect. We conclude that exercise cross-sectional echocardiography is technically difficult but feasible. The mechanical consequences of exercise-induced regional myocardial ischemia can be detected noninvasively by real-time, two-dimensional, cross-sectional echocardiography.REGIONAL left ventricular dysfunction is a hallmark of ischemic heart disease. Segmental left ventricular contraction abnormalities occur within a few seconds after onset of acute myocardial infarction, and appear transiently during episodes of reversible myocardial ischemia. Noninvasive detection of these mechanical consequences of myocardial ischemia and infarction should improve our ability to diagnose and enhance our understanding of coronary heart disease.From the
SUMMARYWe have studied Korotkoff sounds in 10 subjects by recording pressures and sounds simultaneously through a brachial arterial needle at locations both beyond and beneath the inflatable cuff. The Korotkoff sounds coincided with a small dip and ensuing steep rise in pressure immediately beyond the distal edge of the cuff. Sound intensity paralleled not only the rate and the acceleration of this steep ascent, but also the total pressure through which it was maintained. Pressures beneath the midportion of the cuff showed a more pronounced sharp initial negative dip, usually followed by a rapid reversal and steep rise, and the sounds were also recorded here in association with these rapid pressure changes. This study supports the hypothesis that the initial Korotkoff sound is produced by rapid changes of pressure both beneath and distal to the compressing cuff, sufficient in rate to impart sonic vibrations to the vessel wall and surrounding tissues. We have attempted to explain how these rapid pressure changes are produced.
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