Irreversible atrioventricular block requiring a permanent pacemaker implantation is an uncommon complication after AVR. Risk factors are annular calcification, bicuspid aorta, female sex, presence of RBBB or LBBB, prolonged total perfusion time, and hypertension.

Melatonin has been shown to diminish ischemia-reperfusion (I/R) injury in many tissues. The main aim of this study was to evaluate the protective antioxidant effect of melatonin in skeletal muscle during I/R injury. Wistar albino rats were randomly divided into three groups. Hindlimb ischemia was achieved by clamping the common femoral artery in two groups but not in control group. Limbs were rendered ischemic for 1.5 hr; at the end of the reperfusion period of 1.5 hr muscle tissue samples were taken for the histological evaluation and biochemical analysis. Melatonin (10 mg/kg) was injected i.p. in the I/R + Mel group at the onset of ischemia whereas the vehicle solution was injected in the I/R group. In I/R + Mel group histological damage was significantly less than in the I/R group (P < 0.001). In the I/R + Mel group, the mean malonedialdehyde level was lower than in the I/R group (P < 0.01) and was quite near to the levels in the control group (P > 0.05). Glutathione levels were found to be reduced in the I/R group compared with the control (P < 0.01) and I/R + Mel group (P < 0.01). Melatonin has a protective effect against I/R injury in skeletal muscle and may reduce the incidence of compartment syndrome, especially after acute or chronic peripheral arterial occlusions.

No abstract

Coronary artery anomalies are not uncommon, occurring in 1.3% (range = 0.3-5.6%) of the population, and are often an incidental finding in asymptomatic patients. Approximately 20% of coronary anomalies have potential for life-threatening complication, including myocardial infarction, arrhythmia, or sudden death early in life or during adulthood. Coronary artery anomalies are composed of a wide variety of disorders. Some, such as anomalous location of a coronary ostium, duplication of coronary arteries, or multiple ostia, become clinically significant only when another cardiac surgical procedure is necessary, and generally, surgical correction is not required in these patients. On the other hand, the diagnosis of anomalous origin of left coronary artery from pulmonary artery or from the opposite sinus with inter-arterial course is an indication for operation. Some anomalies like coronary artery fistulas, myocardial bridging, and coronary aneurysm require operation only when they cause clinical symptoms. Coronary artery anomalies should be included in the differential diagnosis of anginal symptoms, myocardial infarction, arrhythmia, or heart failure, especially in young patients. Increased awareness of these pathologies will lead to earlier diagnosis and treatment of a potentially life-threatening condition.

Hypercholesterolemia is related to increased risk of aortic valve calcification in patients with degenerative and congenital etiology. Preventive treatment of hypercholesterolemia could play an important role to decrease or inhibit development of aortic valve calcification.