李腾
中国医学科学院阜外医院深圳医院 心律失常科
Due to the complicated pathophysiology of cardiac hypertrophy, there are no effective therapies for the treatment of pathological cardiac hypertrophy. Accumulating evidence has demonstrated that circRNAs participate in the pathophysiology of cardiac hypertrophy. In this study, we investigated the regulatory mechanisms of the novel circ_0018553 in angiotensin II (Ang II)-induced cardiac hypertrophy. Circ_0018553 was enriched in endothelial progenitor cell (EPC)-derived exosomes, and circ_0018553 expression was downregulated in a cellular model of Ang II-induced cardiac hypertrophy. Silencing circ_0018553 promoted cardiac hypertrophy in the Ang II-induced cardiac hypertrophy cellular model, while overexpression of circ_0018553 significantly attenuated Ang II-induced cardiac hypertrophy in cardiomyocytes. Moreover, mechanistic studies revealed that circ_0018553 acted as a sponge for miR-4731 and that miR-4731 repressed sirtuin 2 (SIRT2) expression by targeting the 3'UTR of SIRT2. MiR-4731 overexpression promoted cardiac hypertrophy in the Ang II-induced cardiac hypertrophy cellular model, while inhibition of miR-4731 significantly attenuated Ang II-induced cardiac hypertrophy in cardiomyocytes. The rescue experiments showed that miR-4731 overexpression attenuated the protective effects of circ_0018553 overexpression on the cardiac hypertrophy induced by Ang II; SIRT2 silencing also attenuated the protective effects of miR-4731 inhibition on the Ang II-induced cardiac hypertrophy. In conclusion, our results indicated that EPC-derived exosomal circ_0018553 protected against Ang II-induced cardiac hypertrophy by modulating the miR-4731/SIRT2 signaling pathway.
Hypertension research : official journal of the Japanese Society of Hypertension 2023
BACKGROUND:The ECG characteristics of the distal coronary venous system ventricular arrhythmias (VAs) share common features with VAs arising from the aortic cusps or the endocardial left ventricular outflow tract (LVOT) beneath the cusps. The purpose of this study was to identify specific electrocardiographic and electrophysiological characteristics of VAs originating from the distal great cardiac vein (GCV).METHODS:Based on the successful ablation site, patients with idiopathic VAs from the distal GCV, left coronary cusp (LCC) or the subvalvular left ventricular outflow tract (LVOT) area were included in the present study.RESULTS:The final population consisted of 39 patients (35 males, mean age 51 ± 23 years). All VAs displayed a right bundle branch block (RBBB) morphology with inferior axis. Among these patients, 15 were successfully ablated at the GCV, 15 at the LCC and 9 at the subvalvular region. A "w" pattern in lead I was present in 12 out of 15 (80%) VAs originating from the distal GCV compared to none of VAs arising from the other two sites (p < 0.01). VAs with a GCV origin exhibited more commonly increased intrinsicoid deflection time, higher maximum deflection index and wider QRS duration compared to LCC and subvalvular sites (p < 0.05). Acceptable pace mapping at the successful ablation site was achieved in 10 patients. After an average of 36 ± 24 months follow up, 14 (93.3%) patients were free from VAs recurrence.CONCLUSION:A "w" pattern in lead I may distinguish distal GCV VAs from VAs arising from the LCC or the subvalvular region.
BMC cardiovascular disorders 2019
BACKGROUND:Persistent left superior vena cava (PLSVC) is a rare congenital vascular anomaly. Permanent pacemaker implantation (PPI) in patients with PLSVC can be challenging because of the venous anomalies. We reported a case series of patients with PLSVC who underwent PPI with double active fixation leads.METHODS:From January 2012 to July 2016, 9 patients (three male and six females, mean age 68 ± 11 years) with PLSVC who received a dual-chamber pacemaker with double active fixation leads were enrolled retrospectively in this observational study. The indications for pacemaker implantation were symptomatic third-degree atrioventricular block in one and sick sinus syndrome in eight patients.RESULTS:PPI were implanted successfully in all 9 patients. Successful positioning of the ventricular leads at the right ventricular outflow tract (RVOT) septum with a "C" shaped stylet was achieved in 7 patients (77.8%). In the remaining two cases, the ventricular leads were placed in the right ventricular apex and the inferior free wall of the sub-tricuspid annulus. The atrial leads were placed at the lateral wall of the right atrium in all patients. Procedure time and fluoroscopy time were 85.3 ± 11.3 min and 4.5 ± 1.1 min respectively. During a mean follow-up of 4 years, no complications were observed and pacing parameters did not change significantly.CONCLUSION:PPI through PLSVC may be technically feasible, safe, and effective. Double active fixation leads may be standard for patients with PLSVC and most of the ventricular leads could be placed at the RVOT septum.
BMC cardiovascular disorders 2019
