Acute management of unstable angina and non-ST segment elevation myocardial infarction / Tratamento atual da síndrome coronária aguda sem supradesnivelamento do segmento ST

Non-ST segment elevation coronary syndrome usually results from instability of an atherosclerotic plaque, with subsequent activation of platelets and several coagulation factors. Its treatment aims to reduce the ischemic pain, limiting myocardial damage and decreasing mortality. Several antiplatelet and anticoagulation agents have been proven useful, and new drugs have been added to the therapeutic armamentarium in the search for higher anti-ischemic efficacy and lower bleeding rates. Despite the advances, the mortality, infarction and readmission rates remain high.

A síndrome coronária sem supradesnivelamento do ST geralmente resulta da instabilização de uma placa aterosclerótica, com subsequente ativação plaquetária e de diversos fatores de coagulação. O tratamento visa aliviar a dor isquêmica, limitar o dano miocárdico e diminuir a mortalidade. Diversos agentes antiagregantes e anticoagulantes provaram sua utilidade, e novas drogas passaram a compor o arsenal terapêutico, buscando maior eficácia anti-isquêmica e menores índices de sangramento. Apesar dos avanços, as taxas de mortalidade, infarto e reinternação ainda permanecem elevadas.

Cellular retrograde cardiomyoplasty and relaxin therapy for postischemic myocardial repair in a rat model.

We sought to determine whether skeletal myoblasts, wild-type or engineered to express relaxin, might improve myocardial viability and performance in a rat model of chronic myocardial infarction. Our purpose was to investigate a potential new therapy for heart failure. From October 2005 through September 2009, we surgically induced acute myocardial infarction in 80 male Wistar rats. Thirty days after surgery, the rats underwent reoperation for the retrograde coronary venous infusion of skeletal myoblasts, relaxin, or both. The animals were randomly assigned to 4 experimental groups: R1 (the control group, which underwent saline-solution infusion), R2 (systemic relaxin therapy), R3 (myoblast infusion), and R4 (myoblast infusion and systemic relaxin therapy). Echocardiography, positron emission tomography, and cellular and histologic analysis were performed at 4 established time points. Mortality rates were similar among the groups. Postinfarction echocardiographic evaluation revealed similar left ventricular dysfunction. Viable myocardium, evaluated with positron emission tomography, was analogous. After therapy, the echocardiographic values of cardiac function improved significantly (P<0.05) in all groups except R1. Myocardial viability volume increased significantly in groups R3 and R4 (P<0.05) but was unchanged in groups R2 and R1. In group R4, the echocardiographic and positron emission tomographic results improved significantly (P<0.001). Histologic analysis showed that myoblasts settled in regions of ischemic scarring, especially when combined with relaxin. The retrograde venous route is safe, effective, and clinically feasible for cell delivery. Myoblasts and relaxin are better than either alone in terms of myocardial viability and performance improvement.

Ranolazine: a new approach to treating an old problem.

Chronic angina pectoris affects millions of patients every year. During the past 2 decades, advances in medical therapy have led to substantial reductions in the symptoms of angina. Nonetheless, many patients continue to experience persistent angina that causes debilitating symptoms and lifestyle changes. Moreover, many current therapeutic agents cause side effects that can induce substantial morbidity on their own. In major clinical trials, the drug ranolazine has been shown to bring symptomatic relief to large numbers of patients who have chronic angina. Herein, we review the physiology of the sodium channel; the pharmacology of ranolazine; clinical trials that support use of the drug; recent evidence about ranolazine's therapeutic effect on diastolic heart failure, glycemic control, and atrial fibrillation and other arrhythmias; officially approved clinical indications; and avenues of future study.

Effect of panax quinquefolium fruit saponin on hemodynamics and acute myocardial ischemia in coronary artery ligated dogs / 吉林大学学报(医学版)

Objective To observe the effect of panax quinquefolium fruit saponin(PQFS) on hemodynamics and correlative indexes in the coronary artery ligated dogs.Methods The dogs were divided into five groups randomly(n=6): control group,gingkgo leaf tablet group(24 mg?kg~(-1)),24,12 and 6 mg?kg~(-1) PQFS groups.The myocardial infarction size(MIS)and the changes of the serum enzymes were determined by using the acute myocardial infarction models with the ligation of left anterior descending coronary artery of dogs.The parameters of hemodynamics and myocardial oxygen metabolism were measured in the anesthetic dogs with thoracotomy.(Results Compared) with control group,the myocardial blood flow was increased(P

Ameliorative effects of pseudoginsenoside GQ on isoproterenol-induced acute myocardial ischemia in rats / 吉林大学学报(医学版)

Objective To study the ameliorative effects of pseudoginsenoside GQ (PGQ) on electrocardiogram changes in rats with acute myocardial ischemia induced by isoproterenol (ISO). Methods 50 Wistar rats were divided into five groups (n=10) randomly. Group I : i. v. 0.9% sodium chloride water liquor; Group II : i. v. verapamil hydrochloride of 0. 2 mg ? kg-1 ; Group III : i. v. 3. 0 mg ? kg-1 of PGQ; Group IV : i. v. 6. 0 mg ? kg-1 of PGQ; Group V : i. v. 12. 0 mg ? kg-1 of PGQ. Myocardial ischemia was induced by intravenous injection of ISO (2.0 mg ? kg-1). ST-segment changes in the lead II , precordial in lead V1 and precordial in lead V2 were examined. Results In lead II , lead precordial V 1 and lead precordial V 2 , ST-segment elevation of three PGQ groups were not obvious at every time point, the extents of ST-segment elevation were lower than those in sodium chloride water liquor group (P

Protective effects of Diemailing Injection on myocardial ischemia-reperfusion injury in rats / 吉林大学学报(医学版)

Objective To observe the protective effects of Diemailing Injection (DMLI) on myocardial ischemia-reperfusion injury in rats. Methods The myocardial ischemia-reperfusion model was induced by 30 min left anterior descending coronary occulusion and 24 h reperfusion in open-chest anesthetized rats. The changes of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), MB isoenzyme of creatine kinase (CK-MB), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA) contents in serum, and prostacycline (PGI2) and thromboxane A2 (TXA2) levels in plasma were determined. Results In rats treated by DMLI (with dose of 2. 5, 5 and 10 mL ? kg-1 i. v. at 30 min after coronary occulusion), the myocardial ischemia size (MIS) was significantly reduced, the AST, LDH and CK-MB activities in serum and the TXA2 level in plasma were declined, while PGI2 level in plasma and PGI2/TXA2 ratio were increased significantly. In addition, the LPO content in serum declined, SOD and GSH-Px activities in serum were increased markedly. Conclusion DMLI has protective effects on myocardial ischemia-reperfusion injury through improving free radicals metabolism, decreasing TXA2 level in plasma, increasing PGI2 level in plasma and PGI2/TXA2 ratio.