Journal of Innovations in Cardiac Rhythm Management最新文献

Brugada phenocopy (BrP) is the electrocardiographic appearance of a Brugada pattern due to various reversible causes that is completely resolved after the correction of the underlying abnormalities. In this short communication, we describe a 56-year-old man who had a transient BrP induced by hyponatremia due to thiazide diuretic therapy. A detailed review of the literature revealed that hyponatremia represents an uncommon cause of BrP while, in many of the published cases, concomitant electrolyte disturbances such as hyperkalemia were present. However, even isolated hyponatremia may provoke a BrP. Clinicians should be aware of this rare cause of BrP, which is reversible and has a favorable outcome.

Right ventricular (RV) pacing, particularly from the RV apex, causes bilateral ventricular dyssynchrony, reducing systolic and diastolic function, by delayed activation of the lateral left ventricle, resulting in a wide QRS with a left bundle branch block (LBBB) morphology. Alternative pacing strategies, such as His-bundle pacing and LBB area pacing, tend to be more physiological, avoiding this problem. The feasibility of attaining a narrow paced QRS from the RV septum has not been methodically examined. This study aimed to test the hypothesis that, through pacing at select RV septal sites by careful mapping, it is possible to achieve a narrow "paced QRS," facilitating physiological pacing. The underlying assumption is that a narrow paced QRS prevents long-term deterioration of cardiac function. During dual-chamber pacemaker implantation with standard active fixation leads, the RV septum was mapped carefully before fixing the lead. A characteristic spike potential was identified at some sites which, on stimulation, yielded a narrow paced QRS. The paced QRS duration was measured at different mapping sites; the narrowest paced complex was chosen for long-term pacing. Sixteen consecutive patients underwent pacemaker implantation using this mapping technique. A narrow paced QRS was achieved in 12 patients, whereas narrow paced complexes could not be achieved in 4 patients. Among the 12 narrow paced QRS patients (mean age, 81.5 ± 8.2 years), the indication for pacing was atrioventricular block in 6 patients and sick sinus syndrome in 6 patients. Two patients showed a negative paced QRS in leads 1 and aVL, suggesting an early left-sided septal activation. In the 12 narrow paced QRS patients, the post-pacing mean QRS duration (121.5 ± 14.9 ms) was not significantly different from the pre-pacing mean QRS duration (118.2 ± 23.5 ms) (P > .5); the QRS morphology was normal in seven patients, while four patients had LBBB and one patient had right bundle branch block. In all 12 patients, the narrowest paced complex was associated with a characteristic potential in the endocardial electrogram. Detailed RV septal mapping can yield a narrow paced QRS associated with a characteristic endocardial potential in the pre-pacing electrogram, suggesting possible direct native conduction system access.

The differential diagnosis for wide complex tachycardia includes all causes of narrow complex tachycardia with bundle branch block, all causes of narrow complex tachycardia with antegrade pre-excitation, ventricular tachycardia, and antidromic and other pre-excited reciprocating tachycardias. The variation in a specific intracardiac interval that causes a subsequent change in the tachycardia cycle length or another intracardiac interval can be diagnostic in these arrhythmias.

Left bundle branch area pacing (LBBAP) is a promising pacing technique aimed at mitigating pacing-induced cardiomyopathy; however, a gap in understanding persists concerning intraprocedural complications and their management. This case study sheds light on a rare complication associated with LBBAP. Through sheath penetration into the interventricular septum at a typical site, a septogram revealed the dissection of a large septal coronary vein. Herein, we propose the management strategy and its outcome.

Pulsed field ablation uses irreversible electroporation to interrupt cellular membranes and induce myocyte apoptosis. Reversible electroporation has been used in other specialties, but its utility in cardiac ablation is unknown. Here, a 69-year-old woman undergoing repeat ablation for atypical atrial flutter presented with extensive scar after cardiac surgery (including MAZE) and previous ablation, leading to a macro re-entry circuit. To minimize superfluous lesions and further arrhythmia, we used a single pulse confirming the isthmus location, with cessation of the arrhythmia. As a conclusion, reversible electroporation may be used to test areas of interest prior to irreversible lesion creation.

Heart failure (HF) is a complex and potentially life-threatening medical condition posing significant risks to individuals. It is associated with substantial health care expenditures, considerable morbidity and mortality, and a decline in functional capacity and quality of life. Cardiac contractility modulation (CCM) has emerged as a promising device-based treatment for patients with HF with reduced ejection fraction (HFrEF). Studies have shown that CCM treatment in HFrEF patients can improve exercise tolerance and quality of life and reduce HF hospitalizations. As CCM therapy becomes a more prevalent treatment for HFrEF, the natural learning curve inherent in the use of new technologies necessitates broader provider training and careful patient follow-up. To that end, this article highlights the importance of developing a fundamental troubleshooting algorithm to help optimize the management of patients who have an implanted CCM device.