Emergency coronary stenting for complete thrombotic occlusion of an unprotected left main coronary artery in acute myocardial infarction complicated by cardiogenic shock in an octogenarian patient--a case report.

This report concerns an 82-year-old white man, who was admitted with cardiogenic shock secondary to an acute anterior myocardial infarction with right bundle branch block requiring an intra-aortic balloon pump for hemodynamic support and mechanical ventilatory support for respiratory distress. An immediate cardiac catheterization with coronary angiography revealed a complete thrombotic occlusion of the left main coronary artery. Prompt stent-supported percutaneous transluminal coronary angioplasty to the occluded left main coronary artery, a critical stenosis of the ostial left anterior descending artery, and the left circumflex coronary artery, allowed for recovery from this life-threatening condition and subsequent discharge from the hospital of this octogenarian patient. It is suggested that in a critical clinical condition with particularly challenging coronary anatomical findings, stent-supported coronary angioplasty can be lifesaving treatment in selected patients with octogenarian status with acute myocardial infarction.

Simultaneous measurement of coronary flow reserve by left anterior descending coronary artery Doppler and great cardiac vein thermodilution methods.

OBJECTIVES: The objective of this study was to compare left anterior descending coronary artery Doppler blood flow velocity and great cardiac vein thermodilution blood flow measurements of coronary flow reserve and submaximal coronary vasodilation in humans. BACKGROUND: Reported maximal coronary flow reserve values obtained with the coronary venous thermodilution method are lower than those obtained with other measurement methods. METHODS: Thermodilution measurements of great cardiac vein flow in 11 subjects were compared with simultaneous Doppler measurements of changes in left anterior descending coronary flow velocity after intracoronary administration of papaverine, nitroglycerin, iohexol and intravenous administration of dipyridamole. RESULTS: Coronary flow reserve (papaverine peak/rest flow ratio) was 3.7 +/- 1.7 (mean +/- SD) by the Doppler method and 2.0 +/- 0.7 by the thermodilution technique (p less than 0.001). Thermodilution flow changes were also smaller than Doppler-measured changes during submaximal vasodilation and during prolonged coronary dilation after dipyridamole administration. CONCLUSIONS: Coronary flow reserve and submaximal flow increases measured with the thermodilution method were consistently and substantially smaller than Doppler-derived measurements. This discrepancy has important implications for the comparison of coronary flow reserve measurements performed with the use of different techniques.

Comparison of coronary vasodilation with intravenous dipyridamole and adenosine.

Although both intravenous dipyridamole and adenosine have been used to produce coronary vasodilation during cardiac imaging, the relative potency of the commonly administered doses of these agents has not been evaluated. Accordingly, the coronary and systemic hemodynamic effects of intravenous adenosine (140 micrograms/kg per min) and intravenous dipyridamole (0.56 mg/kg over 4 min) were compared with a maximally dilating dose of intracoronary papaverine in 15 patients. Coronary blood flow responses were assessed using a Doppler catheter in a nonstenotic coronary artery. The protocol was discontinued in two patients because of transient asymptomatic atrioventricular (AV) block during adenosine infusion. The mean heart rate increased more with adenosine (11 +/- 9 beats/min) and dipyridamole (11 +/- 7 beats/min) than with papaverine (4 +/- 3 beats/min, p less than 0.05 vs. adenosine and papaverine). The mean arterial pressure decreased less with dipyridamole (-10 +/- 3 mm Hg) and papaverine (-9 +/- 4 mm Hg) than with adenosine (-16 +/- 5 mm Hg, p less than 0.01 vs. dipyridamole and papaverine). The peak/rest coronary blood flow velocity ratio was greater with papaverine (3.9 +/- 1.1) than with adenosine (3.4 +/- 1.2, p less than or equal to 0.05 vs. papaverine) or dipyridamole (3.1 +/- 1.2, p less than 0.01 vs. papaverine). A larger decrease in coronary resistance as measured by the coronary vascular resistance index occurred with papaverine (0.25 +/- 0.06) and adenosine (0.26 +/- 0.09) than with dipyridamole (0.31 +/- 0.10, p less than 0.01 vs. papaverine, p less than 0.05 vs. adenosine).(ABSTRACT TRUNCATED AT 250 WORDS)

Simultaneous acute thrombosis of two major coronary arteries following intravenous cocaine use.

Myocardial infarction is now a well-recognized complication of cocaine abuse. This report describes a 38-year-old man who sustained simultaneous acute thrombosis of two major epicardial coronary arteries shortly after intravenous cocaine use. The finding of layers of mural thrombus of varying age, from acute to two to three days, in both coronary arteries represents a previously unreported finding (to our knowledge) in cocaine-associated cardiac death. Potential mechanisms for the association between cocaine use and infarction and the cardiac pathologic findings in cocaine-associated death are discussed.

Left ventricular dysfunction due to chronic right ventricular pressure overload. Resolution following percutaneous balloon valvuloplasty for pulmonic stenosis.

Left ventricular dysfunction due to chronic right ventricular pressure overload is well documented in experimental animals, but is controversial in humans. Whether left ventricular dysfunction resolves following the relief of chronic right ventricular pressure overload has not been studied. In this report, rapid improvement in both right and left ventricular function following successful percutaneous balloon valvuloplasty is described in a patient with severe isolated valvular pulmonic stenosis and biventricular dysfunction. It appears that: (1) geometric distortion played a major role in his reversible left ventricular dysfunction, and (2) severe biventricular dysfunction should not be a contraindication to valvuloplasty for valvular pulmonic stenosis.