Effect of hypercholesterolemia on cardiac electrophysiology

    LIU Nian, PU Jun,RUAN Yanª²Fei

    Department of Cardiovasology, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology , Wuhan 430030,China

    ¡¾Abstract¡¿AIM£º To elucidate the effect of hypercholesterolemia on cardiac electrophysiology. METHODS: Rabbits were fed with either high cholesterol or standard chows for 10 weeks. Electrocardiograph, ventricular fibrillation threshold and the level of serum lipid were examined. Wholeª²cell patch clamp technique was used to record Ica,L. RESULTS: High serum cholesterol level and atherosclerosis were observed in high cholesterol group. Ventricular fibrillation threshold was lower in high cholesterol group than that in control group [(11.1¡À1.3) V vs (14.4¡À1.6) V, P<0.05] and QTc intervals were longer in high cholesterol group than those in control group[(334¡À14) ms vs (303¡À12) ms, P<0.05]. The densities of ICa,L were larger in high cholesterol group than those in control group [(15.8¡À1.2) pA/pF vs (11.9¡À1.0) pA/pF, P>0.01]. CONCLUSION: Hypercholesterolemia can produce cardiac electrical remodeling, including increased ICa,L , prolonged repolarization and decreased ventricular fibrillation thresholds. ......