Indian Pacing and Electrophysiology Journal最新文献

Introduction: Pediatric patients with congenital heart disease repair may develop sinus node dysfunction. Leadless pacemakers have provided an alternative option to transvenous and epicardial device implants for pediatric patients in need of ventricular pacing. We describe the first adolescent patient to receive a leadless pacemaker in the atrium due to symptomatic sinus pauses.

Methods: The study was approved by the internal review board of the University of California at Davis. Femoral vein implant was performed of an Aveir VR due to the higher impedance and larger battery capacity.

Results: The 16-year-old male with dextro-transposition of the great arteries and ventricular septal defect repair had an uncomplicated atrial appendage implant of an Atrial Aveir VR, under transesophageal echocardiographic guidance. Three-month follow-up demonstrated stable threshold of 0.5Volts @ 0.2milliseconds, impedance of 720 ohms and sensing of 9.1 millivolts, with 10% pacing and predicted battery longevity of 22.8 years.

Conclusion: Atrial implant of a leadless pacemaker is possible in the older pediatric population without complications, including of the Aveir VR.

Radiofrequency (RF) catheter ablation is the primary treatment for cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL), with cryothermal energy as an alternative. While cryoablation offers comparable effectiveness and safety to RF ablation, it poses a risk of coronary artery spasm leading to ST-elevation. This case report presents a 65-year-old man with drug-refractory atrial fibrillation (AF) and AFL undergoing cryothermal CTI ablation guided by intracardiac echocardiography (ICE). During the procedure, two distinct ST-elevation episodes were observed. The first episode coincided with the pull-down of the cryoablation catheter, potentially resulting in coronary compression, as indicated by ICE, and was rapidly resolved by discontinuing the freezing process. The second episode, occurring without active freezing, was attributed to coronary artery spasm and resolved with intracoronary nitroglycerin administration. During the second episode, emergent right coronary angiography confirmed total occlusion in the segment 4 AV adjacent to the region where cryoablation was performed, which fully resolved post-nitroglycerin. This report underscores the dual mechanisms of ST-elevation-coronary artery compression and spasm-during cryothermal CTI ablation, highlighting the critical role of ICE in enhancing procedural safety.

A 53-year-old patient with a history of heart transplant is referred for atrial tachycardia ablation. Two dissociated concomitant rhythms are observed: a focal atrial tachycardia in the donor atrium and atrial fibrillation in the remaining recipient atrium.

Background: Macroreentrant atrial tachycardia (ATs) through epicardial conduction is depicted as a focal AT on 3-D mapping, i.e., pseudo-focal AT. A new feature of the Rhythmia mapping system (Boston Scientific), the "LUMIPOINT module", can highlight all electrocardiograms (EGMs) above a threshold determined by an adjustable confidence slider (CS). Lowering the CS (L-CS) may highlight undetected electrograms (EGMs) at the nominal CS setting, potentially enabling visualization of the critical isthmus of pseudo-focal ATs.

Methods and results: This study included 3 ATs after linear ablation of two left atrial roof-dependent ATs (cases 1 and 2) and one peri-mitral flutter (case 3). All ATs were diagnosed as pseudo-focal AT according to an electrophysiological study and the Rhythmia mapping system with the LUMIPOINT module. The L-CS method consisted of the following steps: 1. Set the LUMIPOINT activation window to the time difference before and after the linear ablation line. 2. Highlight the two regions before and after the linear ablation line. 3. Gradually lower the CS value from the nominal setting of 85 % by 5-10 %. By the L-CS method in cases 1-3, the 2-sided highlighted areas before and after the prior linear ablation lesion gradually expanded and eventually fused. EGMs at the fusion sites of the highlighted areas exhibited fragmented EGMs with a low voltage, where a single-shot ablation terminated the targeted ATs.

Conclusion: The L-CS method was useful for the visualization of residual gaps and identification of targeted ablation sites in cases of pseudo-focal AT after linear ablation of macroreentrant ATs.

Patients with concurrent heart failure (HF) and atrial fibrillation (AF) have poor outcomes. Randomized clinical trials comparing rhythm control approaches to rate control of AF have yielded conflicting results and there is a paucity of updated and comprehensive evidence summaries to inform best practice in HF patients. We therefore conducted a systematic review and meta-analysis to compare outcomes with rhythm versus rate control of AF in various subgroups of HF patients. In HF patients overall, we found high certainty evidence that rhythm control decreased all-cause and cardiovascular mortality (hazard ratio [HR, 95 % confidence interval] 0.64 [0.43-0.94]) and HR 0.50 [0.34-0.74] respectively). Rhythm control was associated with decreased HF hospitalization (risk ratio [RR] 0.79 [0.63-0.99], moderate certainty), but did not significantly decrease thromboembolic events (RR 0.67 [0.32-1.39], low certainty). The mean difference in left ventricular ejection fraction [LVEF] from baseline to last follow-up was greater in rhythm control group by 6.01 % [2.73-9.28 %] compared with rate control. Subgroup analyses by age, HF etiology (ischemic or non-ischemic), LVEF, presence of diabetes and hypertension did not reveal any significant differences in treatment effect. The survival and hospitalization reduction benefit of rhythm control of AF in HF patients likely reflects the success of catheter ablation especially in HF with reduced ejection fraction. These data are important to guide shared decision-making when managing AF in HF patients.

A patient with a dual-chamber pacemaker for sick sinus syndrome was hospitalized for heart failure. The electrocardiography (ECG) during hospitalization displayed seemingly abnormal pacing artifacts. This report focuses on the problem-solving of an abnormal-looking paced ECG and identifies the pacemaker's operational behavior as the underlying reason.

We described a premature ventricular contraction arising from the left coronary sinus cusp, in which we discussed about the interpretations of the signals recorded there. Our case provided further insights into the interpretation of signals recorded at the coronary sinus cusp during premature ventricular contraction ablation.