Nihan Kayalar

Melatonin protects against ischemia/reperfusion injury in skeletal muscle.

Abstract:  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.

Congenital Coronary Anomalies and Surgical Treatment

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.

Concomitant Septal Myectomy at the Time of Aortic Valve Replacement for Severe Aortic Stenosis

BACKGROUND Left ventricular outflow tract obstruction may be unmasked after a successful aortic valve replacement (AVR) for severe aortic stenosis in the setting of asymmetrical basal septal hypertrophy (ABSH). The quantitative assessment of the obstructive potential of ABSH adjacent to a severely stenotic valve can be challenging. We reviewed our experience with patients who underwent concomitant septal myectomy at the time of AVR for severe aortic stenosis. METHODS During the 10-year period ending January 2009, 3,523 patients underwent AVR for the primary indication of severe aortic stenosis. Forty-seven of these patients underwent concomitant septal myectomy. Preoperative and postoperative echocardiograms, operative data, hospital course, morbidity, and mortality were assessed. RESULTS The mean age of the group was 73 +/- 11 years. The mean aortic valve area was 0.74 cm(2) preoperatively. On preoperative transthoracic echocardiography, only 28% of the patients were considered to be at risk for possible left ventricular outflow tract obstruction. The mean left ventricular mass index decreased from 113.7 +/- 24.3 g preoperatively to 90.0 +/- 17.2 g at 1 year after the surgery (p < 0.001). The operative mortality was 2%. Complete heart block was observed in 2 patients (4.2%), and no iatrogenic ventricular septal defect was noted. CONCLUSIONS A quantitative assessment of the obstructive ABSH in the setting of severe aortic stenosis may be difficult preoperatively. Surgeons should inspect left ventricular outflow tract for possible obstructive ABSH at the time of AVR. Concomitant myectomy is a safe and effective procedure without additional complications and should be considered for patients with a preoperative or intraoperative diagnosis of ABSH even though dynamic obstruction was not demonstrated.

Hypercholesterolemia Association with Aortic Stenosis of Various Etiologies

Abstract  Background: Hypercholesterolemia has been found to be associated with aortic valve stenosis and to resemble the inflammatory process of atherosclerosis in many studies. The aim of this study was to investigate the role of hypercholesterolemia in development of aortic valve calcification in different etiologies. Methods: The study included 988 patients with rheumatic, congenital, or degenerative aortic stenosis, who underwent aortic valve replacement at Koşuyolu Heart and Research Hospital between 1985 and 2005. Effects of hypercholesterolemia and high low‐density lipoprotein level on calcific aortic stenosis or massive aortic valve calcification were analyzed for each etiologic group. Results: Both univariate and multivariate analyses revealed that the high serum cholesterol level (>200 mg/dL) was related to massive aortic valve calcification in all patients (p = 0.003). Hypercholesterolemia was linked to calcific aortic stenosis and massive calcification in patients with degenerative etiology (p = 0.02 and p = 0.01, respectively) and it was related to massive calcification in patients with congenital bicuspid aorta (p = 0.02). Other independent risk factors for calcific aortic stenosis and massive calcification in the degenerative group were high low‐density lipoprotein level (>130 mg/dL; p = 0.03 and p = 0.05, respectively) and high serum C‐reactive protein level (p = 0.04 and p = 0.05, respectively). Conclusions: 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.

Time from cardiac catheterization to cardiac surgery: a risk factor for acute kidney injury?

OBJECTIVES Acute kidney injury can occur after cardiac catheterization and cardiac surgery. The negative effects of the contrast media and cardiopulmonary bypass on renal function may be additive when performed in close succession. The results in the literature are, however, conflicting. METHODS Preoperative, operative, perioperative and postoperative variables of 573 consecutive adult patients who underwent cardiac surgery on cardiopulmonary bypass were collected prospectively. Acute kidney injury (AKI) was defined according to the Acute Kidney Injury Network criteria based on changes in serum creatinine level within 48 h of surgery. RESULTS Acute kidney injury was detected in 233 patients (41%). In a multivariate analysis, older age (P = 0.01), longer cardiopulmonary bypass time (P = 0.003), lower preoperative haematocrit level (P = 0.02) and higher body mass index (P = 0.001) were found to be independently associated with development of acute kidney injury. Analysis of the time from cardiac catheterization to surgery by logistic regression modelling did not show any significant change in the risk of acute kidney injury. Risk related to time from catheterization to surgery was not increased even in the patients with elevated preprocedural creatinine levels (>106 μmol l(-1); P = 0.23), left ventricular dysfunction (ejection fraction <40%; P = 0.19) and older age (≥70 years; P = 0.86). CONCLUSIONS The time from cardiac catheterization to cardiac surgery is not a risk factor for the development of postoperative acute kidney injury even in patients with other risk factors. Surgical intervention should not be delayed in emergency or urgent cases. The optimization of renal function seems to be the correct strategy in clinically stable patients with risk factors for acute kidney injury.

Concomitant surgery for renal neoplasm with pulmonary tumor embolism

OBJECTIVE Gross tumor pulmonary embolism from renal carcinoma is rarely diagnosed preoperatively. Individual cases of intraoperative embolization of tumor during radical resection of the kidney have been reported. We report on 9 patients who underwent pulmonary arterial tumor removal concomitant with nephrectomy. METHODS Between 2000 and 2008, 9 patients underwent simultaneous nephrectomy and removal of gross embolic tumor from the pulmonary arteries. In 7 of these patients the diagnosis was made preoperatively by either computed tomography or magnetic resonance imaging. Cardiopulmonary bypass was used in all cases. Bilateral removal of pulmonary artery tumor was required in 7 patients and unilateral in 2. RESULTS All patients survived to hospital discharge after a median stay of 8.8 days (mean, 6-17 days). Two patients are currently alive 4 and 56 months after the operation. Six patients died of distant metastasis or local recurrence of disease after 6, 9, 12, 17, 25, and 29 months. Actuarial survival at 6 months, 1, 2, and 3 years was 100%, 75%, 50%, and 25%, respectively. CONCLUSIONS Pulmonary artery embolic tumor removal concomitant with nephrectomy for renal carcinoma can be performed safely. Survival of patients with combined surgery is comparable with that of patients with the same stage of renal neoplasm without pulmonary tumor embolism. The pulmonary tumor embolism in patients with renal carcinoma should be considered as extension of vena caval tumor but not as a distant metastasis. Pulmonary tumor removal provides symptomatic relief and may provide a survival benefit in these patients.

A New Use of Fogarty Catheter: Chest Tube Clearance

Chest tubes are commonly used for patients who have undergone a cardiothoracic procedure to avoid the complications related to the accumulation of blood and serous fluid in the chest. Although the traditional methods such as milking, stripping or active chest tube clearance devices are used to establish patency of the chest tubes, they can become clogged at any time after their placement. Our technique may re-establish the tube patency with utilising Fogarty catheter and without any detriment to tissues.

Popliteal artery pseudoaneurysm associated with solitary osteochondromatosis

Osteochondroma is the most common benign tumor of the bone, seen mostly during adolescence. In the current study, we report a 19-year-old male patient with a two-week history of pain and swelling of the medial side of his right thigh just above the knee without any trauma. CT angiography revealed a popliteal artery pseudoaneurysm and its close relationship with a femoral osteochondroma. Surgical repair consisted of repair of pseudoaneurysm and removal of osteochondroma. In young patients, a non-traumatic pseudoaneurysm of distal femoral artery may be a complication of an osteochondroma and this treatable pathology should be looked for to prevent recurrence.

Impact of coronary collateral circulation and severity of coronary artery disease in the development of postoperative atrial fibrillation

OBJECTIVES Atrial fibrillation (AF) after cardiac surgery has been reported to be approximately 30%, making it one of the most important causes of morbidity and mortality post surgery. Although various clinical and laboratory predictors and underlying mechanisms progressing to postoperative AF have been proposed, the role of ischaemia in pathogenesis is doubtful. In this study, the association of coronary collateral circulation (CCC) and severity of coronary artery disease (CAD) with the development of postoperative AF was investigated. METHODS A total of 597 patients who underwent on-pump coronary artery bypass surgery were included in the study. Pre-, peri- and postoperative variables were recorded in a computerized database. CCC and severity of CAD were documented for each patient according to Rentrop classification and Gensini score. RESULTS Postoperative AF was observed in 96 patients (16.1%). Advanced age, female gender, presence of hypertension and low haematocrit level were significantly associated with postoperative AF. By contrast, CCC and severity of CAD were not associated with postoperative AF (P = 0.22 and 0.5, respectively). Older age and lower preoperative haematocrit levels were the major predictors of postoperative AF development in the multivariate regression analysis. CONCLUSIONS CCC and severity of CAD did not have a significant effect on the occurrence of postoperative AF, suggesting an ineffective role of myocardial ischaemia in the development of this condition.

Left atrial leiomyosarcoma extending into the posterior mediastinum and mimicking a left atrial myxoma.

BACKGROUND Intracardiac malignancies are extremely rare and hard to detect or differentiate preoperatively. CASE REPORT We present a 48-year-old female patient who was diagnosed primarily with left atrial myxoma and taken into emergency surgery. The tumor extended into the pulmonary veins and infiltrated the atrial endocardium, and the histopathologic diagnosis was leiomyosarcoma. The left atrial endocardium was successfully peeled off with the tumor and complete resection was achieved. CONCLUSION The possible malignant nature of intracardiac masses should be kept in mind, especially in middle-aged patients. The extent of the tumor must be determined in elective cases to establish the proper strategy for complete resection, which is the only chance of successful treatment for this lethal disease entity. Endocardial peeling is warranted for successful removal of the tumor mass in leiomyosarcoma.