Relationship between resistin levels and left ventricular end-diastolic pressure and coronary artery disease

Resistin is a cysteine-rich peptide evaluated in several studies to search its relationship with atherosclerosis, coronary artery disease (CAD) and heart failure. There is no data in the literature about the relationship between serum resistin levels and left ventricular end-diastolic pressure (LVEDP). The primary endpoint of this study is to evaluate the association between resistin levels with LVEDP. Secondary endpoints of this study are; to evaluate the relationship between resistin levels and severity of CAD, carotid intima-media thickness (CIMT), echocardiographic diastolic dysfunction parameters. One hundred and twenty-eight nondiabetic patients with the indications of invasive coronary angiography (CAG) were included in the study. Patients with hypervolemia, diabetes mellitus, insulin resistance, acute coronary syndrome, severe valvuler disease, high creatinine, obesity, active enfection, malignity were excluded from the study. Severe CAD is defined as ≥ 50% stenosis in at least one of major coronary arteries. Serum resistin levels were measured by ELISA method before CAG. Severity of CAD was evaluated by Gensini score and LVEDP was measured during left heart catheterization. Echocardiographic evaluation was performed in the range of ± 12 hours from the time of CAG. Mean age of the study population was 59 ± 12.5 and 85 (66.4%) were male. After CAG, 60 patients (%46.9) had severe CAD, whereas 68 patients (53.1%) did not have severe CAD. The mean LVEDP's were similar for patients with and without severe CAD (19.1 ± 8.0 mmHg vs 18.2 ±7.2 mmHg, respectively, p=0.480). Serum resistin levels also did not differ between the groups (2626.2 ± 1513.3 pg/ml for patients with severe CAD and 3031.9 ± 1638.6 pg/ml for those without severe CAD, p=0.154). There were statistically significant difference between groups with respect to CIMT (0.99 ± 0.34 mm for patients with severe CAD and 0.7 ± 0.19 mm for those without severe CAD, p=0.000). Serum resistin levels were not significantly correlated with ejection fraction (EF) (r=0.110, p=0.228), LVEDP (r=-0.045, p=0.627), CIMT (r=0.082, p=0.457), age (r=-0.056, p=0.535) and Gensini score (r=-0.091, p=0.328). However there were statistically significant correlations between resistin levels and CIMT in hypertensive patients (r=0.282, p=0,041) and patients with severe CAD (r=0.485, p=0.002). There were no significant correlation between resistin levels and echocardiographic diastolic dysfunction parameters. Gensini score was correlated with average e' velocity of lateral and septal wall gained by PW Doppler (r=-0.364, p=0.000), ratio of mitral E wave to average e' velocity of lateral and septal wall gained by PW Doppler (r=0.251, p=0.012), average e' velocity of all walls gained by color tissue Doppler (r=-0.450, p=0.000), ratio of mitral E wave to average e' velocity of all walls gained by color tissue Doppler (r=0.486, p=0.000), left atrium volume index (LAVi) (r=0.232, p=0.038) and isovolumetric relaxation time (IVRT) (r=0.336, p=0.001). In preserved EF patients (EF ≥ 40%), Gensini score was correlated with ratio of mitral E wave to average e' velocity of all walls gained by color tissue Doppler (r=0.327, p=0.006), average e' velocity of lateral and septal wall gained by PW Doppler (r=-0.351, p=0.001), average e' velocity of all walls gained by color tissue Doppler (r=-0.355, p=0.002) and mitral E/A ratio (r=-0.203, p=0.044). In conclusion, serum resistin levels were not correlated with LVEDP, CIMT, severity of CAD, EF and echocardiographic diastolic dysfunction parameters. Resistin levels may be used as a biomarker in hypertensive and severe CAD patients to evaluate CIMT. Further studies with larger patient populations including diabetic patients and patients with low EF are required to predict the value of resistin in clinical use.