The Association between Subclinical Hypothyroidism and Epicardial Adipose Tissue Thickness

BACKGROUND AND OBJECTIVES: Subclinical hypothyroidism (SH) is considered to be a potential risk factor for cardiovascular disease. Epicardial adipose tissue (EAT) thickness is also closely related to cardiovascular disorders. The aim of this study was to evaluate whether SH is associated with higher EAT thickness. SUBJECTS AND METHODS: Fifty-one consecutive patients with SH and 51 healthy control subjects were prospectively enrolled into this trial. Thyroid hormone levels, lipid parameters, body mass index, waist and neck circumference, and EAT thickness measured by echocardiography were recorded in all subjects. RESULTS: Mean EAT thickness was increased in the SH group compared to the control group (6.7+/-1.4 mm vs. 4.7+/-1.2 mm, p<0.001). EAT thickness was shown to be correlated with thyroid stimulating hormone level (r=0.303, p=0.002). Multivariate logistic regression analysis revealed that EAT thickness was independently associated with SH {odds ratio (OR): 3.87, 95% confidence interval (CI): 1.92-7.78, p<0.001; OR: 3.80, 95% CI: 2.18-6.62, p<0.001}. CONCLUSION: Epicardial adipose tissue thickness is increased in patients with SH compared to control subjects, and this increase in EAT thickness may be associated with the potential cardiovascular adverse effects of SH.

Electrophysiologic effects of statins in patients with ischemic cardiomyopathy and ventricular tachyarrhythmia

Statin therapy may be beneficial not only to reduce the risk of vascular events but also to reduce the risk of ventricular arrhythmias and sudden cardiac death. We evaluated the effects of statins on electrophysiologic parameters in patients with ischemic cardiomyopathy and established ventricular tachyarrhythmia. Prospective study. Eleven patients [all male, mean age 57.9 +/- 6.64 years], with ischemic cardiomyopathy and ventricular tachyarrhythmia on admission were included in the study. Two academic tertiary care centers. A baseline electrophysiologic study was performed before implantable-cardioverter defibrillator [ICD] implantation. Forty milligram of atorvastatin was started and electrophysiologic study was repeated one month later and results were compared. Basic intervals, corrected sinus node recovery time [cSNRT], sino-atrial conduction time [SACT], atrio-ventricular node refractory period [AVNRP], atrio-ventricular Wenckebach period [AVWP], ventricular refractory period [VRP], ventriculo-atrial dissociation measurement, corrected QT [QTc] interval and QT dispersion were measured. Also, ventricular arrhythmia inducibility was evaluated with various techniques. Although, QTc interval and QT dispersion decreased significantly with statin treatment [p < 0.05], there were no statistically significant differences in the measurements of basic intervals, cSNRT, SACT, AVNRP, AVWP, VRP and ventriculo-atrial dissociation compared to pretreatment measurements [p > 0.05]. Additionally, while induction of ventricular tachyarrhythmia occurred in 72.7% of patients before statin therapy, this rate decreased to 36.4% with treatment [p - 0.13]. Statin treatment led to significant decreases in QTc interval and QT dispersion, but it did not change other electrophysiologic parameters significantly