Heavy cigarette smoking has negative effect on autonomic function. HRT is an appropriate noninvasive method to evaluate the effect of cigarette on autonomic function. Simultaneous abnormal HRT and HRV values may explain increased cardiovascular event risk in heavy cigarette smokers.
This study was sought to examine the effects of repetitive monomorphic premature ventricular contractions (PVCs) on left ventricular (LV) diastolic function. Thirty-three symptomatic patients (Study group, 10 males, mean age 40 +/- 8 years) with normal LV systolic function and repetitive PVCs originating from the right ventricular outflow tract (RVOT-PVCs) on 24-h Holter monitoring, and 30 healthy controls (Control group, 9 males, mean age 37 +/- 9 years) were enrolled in the study. None of the patients had structural heart disease. Diastolic function was assessed by echocardiographic mitral inflow pattern and tissue Doppler imaging. The study group displayed a lower E/A ratio, longer isovolumetric relaxation time (IVRT), and longer E-wave deceleration time (EDT). In the study group 13 patients showed impaired relaxation. While mean values of the systolic velocity (Sa), early diastolic velocity (Ea), and early/late diastolic velocity (Ea/Aa) ratio were significantly lower in the study group, the Aa velocity and E/Ea ratio were significantly higher. Ea velocity was <10 cm/s in 7 study patients. Mitral inflow pattern and Ea velocity was normal in all controls. Significant correlations were found between ventricular premature beats percentage and early to late transmitral flow velocity ratio, EDT, IVRT, Ea velocity, the Ea/Aa ratio, and the E/Ea ratio. In multivariate analysis, total PVC count and age were found to be independent predictors of impaired relaxation. These results suggest that repetitive monomorphic RVOT-PVCs lead to abnormalities of LV diastolic function that may contribute to clinical symptoms in patients with structurally normal hearts.
Although atrial mechanical functions are preserved in patients with CD, a slower electrical conduction was found, suggesting an increased risk of AF in this group of patients.
Platelets play an important role in the pathogenesis of atherothrombosis. Platelet activation is associated with increased mean platelet volume (MPV) and platelet distribution width (PDW). In this study, we investigated the relation of MPV and PDW with the risk of stroke in patients with intermediate (50%-70%) carotid artery stenosis. A total of 254 patients (115 symptomatic and 139 asymptomatic) with intermediate carotid artery stenosis were enrolled in this study. Symptomatic and asymptomatic patients were compared in regard to MPV and PDW. Mean platelet volume was significantly greater in the symptomatic group compared with the asymptomatic group (11.1 and 9.4 fL, respectively; P < .001). Platelet distribution width was significantly greater in the symptomatic group compared with the asymptomatic group (15.0% and 11.9%, respectively; P < .001). Multivariate regression analysis showed that an MPV ≥10.2 fL and a PDW ≥14.3% were independent predictors of developing symptomatic carotid artery stenosis. Mean platelet volume and PDW are increased in the presence of symptomatic intermediate carotid artery stenosis. Increased MPV and PDW may be independent predictors of developing symptomatic carotid artery plaque.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.