Evaluation of adiponectin and lipoprotein(a) levels in cardiac syndrome X.

AIMS: Low adiponectin and high lipoprotein(a) [Lp(a)] levels are associated with endothelial dysfunction, atherosclerosis, and coronary artery disease. Cardiac syndrome X (CSX) is characterized by anginal symptoms, positive stress test, and documentation of normal epicardial coronary arteries with angiography. In this study we aimed to investigate the relationship between CSX and circulating levels of adiponectin and Lp(a). PATIENTS AND METHODS: We enrolled 53 female patients with CSX and 33 patients as the control group. The diagnosis of CSX was made according to presence of angina, findings suggestive of ischemia during stress electrocardiography or myocardial perfusion scintigraphy, and documentation of normal coronary arteries in coronary angiography. The control group consisted of patients with atypical angina and normal stress electrocardiography test results. Both groups were matched in terms of hypertension, diabetes mellitus, and metabolic syndrome. RESULTS: Adiponectin levels were significantly decreased in patients with CSX (4.57 µg/ml vs. 13.18 µg/ml; p=0.001); however, Lp(a) levels were significantly increased (36.30 mg/dl vs. 7.24 mg/dl; p < 0.001). Low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) concentrations did not differ between the case group and the control group (p=0.14, p=0.62, p=0.64, respectively). There was no significant difference between groups in terms of age, body mass index, waist circumference hypertension, hyperlipidemia, diabetes mellitus, or metabolic syndrome. In multivariate analysis, Lp(a) and adiponectin were found to be independent predictors of CSX. An Lp(a) level of > 21 mg/dl had 84 % sensitivity and 96 % specificity {area under the curve (AUC)= 0.922, p < 0.0001, 95 % CI [0.842-0.970]} and an adiponectin level of ≤ 5.18 µg/ml also had 58.7 % sensitivity and 82.1 % specificity (AUC=0.726, p=0.0003, 95 % CI [0.609-0.823]) for detecting CSX. CONCLUSION: We detected low adiponectin and high Lp(a) levels in patients with CSX and these findings may be related to the microvascular injury in CSX.

Impact of valve surgery on serum osteopontin levels in patients with mitral regurgitation.

OBJECTIVE: Osteopontin (OPN), a sialoprotein present within atherosclerotic lesions, especially in calcified plaques, is linked to the progression of coronary artery disease and heart failure. We assessed the impact of valve surgery on serum OPN and left ventricular (LV) function in patients with mitral regurgitation (MR). METHODS: Thirty-two patients with severe MR scheduled for surgery were included in the study. Echocardiography markers were assessed preoperatively and at 3 months following the surgery and matched with the serum OPN levels. RESULTS: Valve surgery was associated with a reduction of the ejection fraction (EF) from 55.2 ± 6.3 to 48.8 ± 7.1% after surgery, p < 0.001. Following surgery, the OPN level was significantly higher than preoperatively (mean 245, range 36-2,284 ng/ml vs. 76, 6-486 ng/ml, p = 0.007). Preoperative OPN exhibited a slight negative correlation with the EF (r = -0.35, p = 0.04), and a moderate correlation with vena contracta (r = -0.38, p = 0.02). There were no other meaningful correlations between conventional echocardiographic parameters and OPN. CONCLUSION: Following valve surgery due to severe MR, patients exhibited a decrease in EF and an increase in OPN levels. The assessment of preoperative OPN failed to strongly predict probable LV dysfunction.

Assessment of QT interval duration and dispersion in athlete's heart.

An athlete's heart is characterized by morphological and functional changes occurring as a consequence of regular physical exercise. We sought to determine if these physiological changes lead to ventricular repolarization abnormalities in trained athletes. Forty-four trained athletes and 35 sex- and age-matched healthy sedentary controls were included in the study. A 12-lead surface electrocardiogram (ECG) was obtained from all participants. Maximum QT (QTmax) and minimum QT (QTmin) interval durations, QT dispersion (QTd) and corrected QT dispersion (QTcd) were calculated for each ECG record. Heart rate, systolic and diastolic blood pressure values were found to be identical in both groups. QTmax and QTmin interval durations were not statistically different between the athletic and control groups. Similarly, QTd and QTcd did not differ significantly between the two groups. No association was observed between an athlete's heart and ventricular heterogeneity compared with healthy sedentary controls, despite physiological and structural changes.