There is no evidence regarding the effect of stunning on maximization of regional myocardial external work (EW) or efficiency of energy transfer (EET) in relation to regional afterload (end-systolic stress, sigma(es)). To that end, we studied these relationships in both the left anterior descending coronary artery (LADCA) and left circumflex coronary artery regions in anesthetized, open-chest p...

Many case reports have been published of reversible left ventricular dysfunction precipitated by sudden emotional stress. We have evaluated 10 women hospitalized for acute chest pain and dyspnea, mimicking an acute coronary syndrome, after a severe emotional trigger. Those patients, postmenopausal women, presented ST segment alterations on the EKG, minor elevations of cardiac enzymes, and bioma...

To test the hypothesis that persistent myocardial stunning can lead to hibernating myocardium, 13 pigs were chronically instrumented, and persistent stunning was induced regionally by 6 repetitive episodes of 90-minute coronary stenosis (CS) (30% reduction in baseline coronary blood flow [CBF]) followed by full reperfusion every 12 hours. During the 1st CS, CBF fell from 43+/-2 to 31+/-2 mL/min...

BACKGROUND Previous studies have examined only acute effects of enhanced glucose oxidation on postischemic myocardium. The goal of the present study was to examine prolonged functional recovery subsequent to postischemic, intracoronary pyruvate dehydrogenase kinase inhibition with dichloroacetate (DCA) of stunned myocardium in conscious pigs. METHODS AND RESULTS Myocardial stunning was induce...

Despite many advances in percutaneous and surgical interventions in the treatment of coronary artery disease (CAD), up to one-third of patients are still either not candidates or receive suboptimal revascularization. Calpains are a class of calcium-activated non-lysosomal cysteine proteases that serve as a proteolytic unit for cellular homeostasis. Uncontrolled activation of calpain has been fo...

We evaluated the hypothesis that stunning swine myocardium with brief ischemia reduces oxygen demand in the stunned region and increases tolerance of myocardium to longer periods of ischemia. Wall function was quantified with ultrasonic crystals aligned to measure wall thickening, and stunning was achieved with two cycles of left anterior descending coronary artery (LAD) occlusion (10 minutes) ...

Rizvi,Ali, Xian-Liang Tang, Yumin Qiu, Yu-Ting Xuan, Hitoshi Takano, Asad K. Jadoon, and Roberto Bolli. Increased protein synthesis is necessary for the development of late preconditioning against myocardial stunning. Am. J. Physiol. 277 (Heart Circ. Physiol. 46): H874–H884, 1999.—In phase I of this study, the rate of protein synthesis was measured by the incorporation of [3H]leucine into the p...

Kodani, Eitaro, Yu-Ting Xuan, Ken Shinmura, Hitoshi Takano, Xian-Liang Tang, and Roberto Bolli. -Opioid receptor-induced late preconditioning is mediated by cyclooxygenase-2 in conscious rabbits. Am J Physiol Heart Circ Physiol 283: H1943–H1957, 2002. First published July 26, 2002; 10.1152/ajpheart.00150.2002.—Although activation of -opioid receptors is known to induce both early and late preco...

Incomplete recovery of myocardial contraction after reperfusion following brief ischemia is called the "stunning phenomenon" in an animal experiment. A hydrophilic 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor (statin) does not affect this phenomenon, but lipophilic statins further reduce the contraction during reperfusion. The effects of novel hydrophilic rosuvastatin and...

Although activation of delta-opioid receptors is known to induce both early and late preconditioning (PC) against myocardial infarction, the mechanisms for this salubrious effect are unclear. Furthermore, it is unknown whether delta-opioid receptors can also induce late PC against myocardial stunning. By using conscious rabbits (n = 120) in this study, we found that the delta-opioid receptor ag...