Positive late ventricular potentials in nonischemic dilated cardiomyopathy were associated with a higher incidence of sustained ventricular tachycardia (80% vs 18%, p=0.04) and lower Cx43 expression.
Observational (n=16)
Does the presence of late ventricular potentials on SAECG correlate with reduced and heterogeneous Connexin43 expression in patients with nonischemic dilated cardiomyopathy?
In patients with nonischemic dilated cardiomyopathy, the presence of late ventricular potentials on SAECG correlates with reduced and heterogeneous expression of gap junction Connexin43, providing a potential structural mechanism for increased ventricular arrhythmia risk.
Tasa de eventos absoluta: 80% vs 18%
valor p: p=0.04
Nonischemic dilated cardiomyopathy (DCM) is associated with a high risk of sudden cardiac death. Signal-averaged electrocardiography (SAECG) is a useful clinical tool for detecting late ventricular potentials (LP). Gap junction alterations have recently been shown to be involved in the pathogenesis of ventricular arrhythmias in DCM; however, the possible relationship between gap junctional connexin43 (C x 43) expression and SAECG has not yet been evaluated. In the present study 16 patients (47+/-13 years) with DCM who had undergone SAECG testing were evaluated. In each patient, the expression of C x 43 proteins was qualitatively and quantitatively determined using immunoconfocal microscopy and right ventricular biopsy specimens. The level of expression of C x 43 protein was defined as the proportion of tissue area occupied by C x 43 (percent tissue area) in each test area. The abundance and distribution of the C x 43 signal was assessed in relation to LP. Late ventricular potentials were positive in 5 patients (LP (+) group) and negative in 11 patients (LP (-) group). The incidence of sustained ventricular tachycardia in the LP (+) group was higher than that in the LP (-) group (80% vs 18%, p=0.04). The percent tissue area of C x 43 in the LP (+) group was significantly lower than that in the LP (-) group (p=0.02). Furthermore, C x 43 protein in the LP (+) group was distributed more heterogeneously than that in the LP (-) group (p=0.001). The heterogeneous expression of C x 43 protein may contribute to impaired ventricular conduction, which may be related to the LP detected on SAECG.
Kitamura et al. (Wed,) conducted a observational in Nonischemic dilated cardiomyopathy (n=16). Positive late ventricular potentials (LP+) vs. Negative late ventricular potentials (LP-) was evaluated on Incidence of sustained ventricular tachycardia (p=0.04). Positive late ventricular potentials in nonischemic dilated cardiomyopathy were associated with a higher incidence of sustained ventricular tachycardia (80% vs 18%, p=0.04) and lower Cx43 expression.