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.

Lower levels of serum high-density lipoprotein cholesterol are associated with a worse Duke treadmill score in men but not in women.

BACKGROUND: High-density lipoprotein cholesterol (HDL-C) levels are inversely related to the atherosclerotic burden and are higher in women than in men. We aimed to investigate the sex-specific relationship between serum HDL-C levels and the Duke treadmill score (DTS) in this study. MATERIALS AND METHODS: A total of 111 patients (59 men, 42 women) with suspected coronary artery disease (CAD) who underwent exercise treadmill test (EST) were included. Fasting blood samples were obtained for the assessment of serum lipid levels. DTS was calculated for each patient based on EST findings including ST segment deviation and symptoms. RESULTS: Patients were categorized into a moderate to high risk group based on the DTS score (group-I: 38 patients) and a low risk group (group-II: 63 patients). There was a significant positive correlation between serum HDL-C levels and DTS (r = 0.230; P=0.021). The mean HDL-C level was significantly higher in group-II relative to group-I (49.25 ±11.21 vs. 44.43 ± 11.18, respectively, P = 0.04). An HDL-C level less than the cut-off value of 41.39 mg/dL predicted a moderate to severe risk DTS with 65% sensitivity and 69% specificity in men (area under curve = 0.732, P = 0.004), but not in women (area under curve = 0.505, P = 0.958). After adjustment for traditional CAD risk factors (age, sex, and smoking status), the relationship of DTS to HDL-C remained significant. (P = 0.030; adjusted OR = 0.948 [95% CI, 0.904-0.995]). CONCLUSION: Low HDL-C levels may be associated with a moderate to high risk Duke treadmill score in men, but not in women. Further research is required to clarify the sex-specific relationship between HDL-C and DTS.