Expedited loading with intravenous sotalol is safe and feasible-primary results of the Prospective Evaluation Analysis and Kinetics of IV Sotalol (PEAKS) Registry.

BACKGROUND: Loading of oral sotalol for atrial fibrillation requires 3 days, frequently in the hospital, to achieve steady state. The Food and Drug Administration approved loading with intravenous (IV) sotalol through model-informed development, without patient data. OBJECTIVE: We present results of the first multicenter evaluation of this recent labeling for IV sotalol. METHODS: The Prospective Evaluation Analysis and Kinetics of IV Sotalol (PEAKS) Registry was a multicenter observational registry of patients undergoing elective IV sotalol load for atrial arrhythmias. Outcomes, measured from hospital admission until first outpatient follow-up, included adverse arrhythmia events, efficacy, and length of stay. RESULTS: Of 167 consecutively enrolled patients, 23% were female; the median age was 68 (interquartile range, 61-74) years, and the median CHA2DS2-VASc score was 3 (interquartile range, 2-4). Overall, 99% were admitted for sotalol initiation (1% for dose escalation), with a target oral sotalol dose of either 80 mg twice daily (85 [51%]) or 120 mg twice daily (78 [47%]); 62 patients (37%) had an estimated creatinine clearance ≤90 mL/min. On presentation, 40% of patients were in sinus rhythm, whereas 26% underwent cardioversion before sotalol infusion. In 2 patients, sotalol infusion was stopped for bradycardia or hypotension. In 6 patients, sotalol was discontinued before discharge because of QTc prolongation (3), bradycardia (1), or recurrent atrial arrhythmia (2). The mean length of stay was 1.1 days, and 95% (n = 159) were discharged within 1 night. CONCLUSION: IV sotalol loading is safe and feasible for atrial arrhythmias, with low rates of adverse events, and yields shorter hospitalizations. More data are needed on the minimal duration required for monitoring in the hospital.

His-Purkinje Conduction System Pacing Optimized Trial of Cardiac Resynchronization Therapy vs Biventricular Pacing: HOT-CRT Clinical Trial.

BACKGROUND: His-Purkinje conduction system pacing (HPCSP) using His bundle pacing (HBP) or left bundle branch pacing (LBBP) has emerged as an alternative to biventricular pacing (BVP) in patients requiring cardiac resynchronization therapy (CRT). OBJECTIVES: The aim of the study was to compare the feasibility and clinical efficacy of HOT-CRT (His-Purkinje conduction system pacing Optimized Trial of Cardiac Resynchronization Therapy) with BVP in patients with heart failure, reduced ejection fraction, and indication for CRT. METHODS: This was a prospective, randomized, controlled trial of HOT-CRT and BVP in patients with LVEF <50% and indications for CRT. If HPCSP resulted in incomplete electrical resynchronization, a coronary sinus (CS) lead was added. The primary outcome was the change in left ventricular ejection fraction (LVEF) at 6 months. The primary safety endpoint was freedom from major complications. RESULTS: A total of 100 patients (female 31%, aged 70 ± 12 years, LVEF 31.5% ± 9.0%) were randomized. HOT-CRT was successful in 48 of 50 (96%) and BVP-CRT in 41 of 50 (82%) patients (P = 0.03). QRS duration significantly decreased from 164 ± 26 ms to 137 ± 20 ms with HOT-CRT and 166 ± 28 ms to 141 ± 19 ms with BVP. Fluoroscopy results (18.8 ± 12.4 min vs 23.8 ± 12.4 min, P = 0.05) and procedure duration (119 ± 42 min vs 114 ± 36 min, P = 0.5) were similar. The primary outcome of change in LVEF at 6 months was greater in HOT-CRT than in BVP (12.4% ± 7.3% vs 8.0% ± 10.1%, P = 0.02). The primary safety endpoint was similar (98% vs 94%, P = 0.62). Echocardiographic response of improvement in LVEF >5% occurred in 80% vs 61% (P = 0.06). Complications occurred in 3 (6%) in HOT-CRT vs 10 (20%) in BVP (P = 0.03). CONCLUSIONS: HPCSP-guided CRT resulted in greater change in LVEF compared with BVP. Randomized clinical trials with long-term follow-up are necessary. (His-Purkinje Conduction System Pacing Optimized Trial of Cardiac Resynchronization Therapy [HOT-CRT]; NCT04561778).

Conduction system pacing versus conventional pacing in patients undergoing atrioventricular node ablation: Nonrandomized, on-treatment comparison.

Background: Atrioventricular node ablation (AVNA) with right ventricular or biventricular pacing (conventional pacing; CP) is an effective therapy for patients with refractory atrial fibrillation (AF). Conduction system pacing (CSP) using His bundle pacing or left bundle branch area pacing preserves ventricular synchrony. Objective: The aim of our study is to compare the clinical outcomes between CP and CSP in patients undergoing AVNA. Methods: Patients undergoing AVNA at Geisinger Health System between January 2015 and October 2020 were included in this retrospective observational study. CP or CSP was performed at the operators' discretion. Procedural, pacing parameters, and echocardiographic data were assessed. Primary outcome was the combined endpoint of time to death or heart failure hospitalization (HFH) and was analyzed using Cox proportional hazards. Secondary outcomes were individual outcomes of time to death and HFH. Results: AVNA was performed in 223 patients (CSP, 110; CP, 113). Age was 75 ± 10 years, male 52%, hypertension 67%, diabetes 25%, coronary disease 40%, and left ventricular ejection fraction (LVEF) 43% ± 15%. QRS duration increased from 103 ± 30 ms to 124 ± 20 ms (P < .01) in CSP and 119 ± 32 ms to 162 ± 24 ms in CP (P < .001). During a mean follow-up of 27 ± 19 months, LVEF significantly increased from 46.5% ± 14.2% to 51.9% ± 11.2% (P = .02) in CSP and 36.4% ± 16.1% to 39.5% ± 16% (P = .04) in CP. The primary combined endpoint of time to death or HFH was significantly reduced in CSP compared to CP (48% vs 62%; hazard ratio 0.61, 95% confidence interval 0.42-0.89, P < .01). There was no reduction in the individual secondary outcomes of time to death and HFH in the CSP group compared to CP. Conclusion: CSP is a safe and effective option for pacing in patients with AF undergoing AVNA in high-volume centers.

Clinical outcomes of conduction system pacing compared to biventricular pacing in patients requiring cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) with biventricular pacing (BVP) is well-established therapy in patients with reduced left ventricular ejection fraction (LVEF) and bundle branch block or indication for pacing. Conduction system pacing (CSP) using His-bundle pacing (HBP) or left bundle branch area pacing (LBBAP) has been shown to be a safe and more physiological alternative to BVP. OBJECTIVE: The purpose of this study was to compare the clinical outcomes between CSP and BVP among patients undergoing CRT. METHODS: This observational study included consecutive patients with LVEF ≤35% and class I or II indications for CRT who underwent successful BVP or CSP at 2 major health care systems. The primary outcome was the composite endpoint of time to death or heart failure hospitalization (HFH). Secondary outcomes included subgroup analysis in left bundle branch block as well as individual endpoints of death and HFH. RESULTS: A total of 477 patients (32% female) met inclusion criteria (BVP 219; CSP 258 [HBP 87, LBBAP 171]). Mean age was 72 ± 12 years, and mean LVEF was 26% ± 6%. Comorbidities included hypertension 70%, diabetes mellitus 45%, and coronary artery disease 52%. Paced QRS duration in CSP was significantly narrower than BVP (133 ± 21 ms vs 153 ± 24 ms; P <.001). LVEF improved in both groups during mean follow-up of 27 ± 12 months and was greater after CSP compared to BVP (39.7% ± 13% vs 33.1% ± 12%; P <.001). Primary outcome of death or HFH was significantly lower with CSP vs BVP (28.3% vs 38.4%; hazard ratio 1.52; 95% confidence interval 1.082-2.087; P = .013). CONCLUSION: CSP improved clinical outcomes compared to BVP in this large cohort of patients with indications for CRT.

Clinical outcomes of left bundle branch area pacing compared to right ventricular pacing: Results from the Geisinger-Rush Conduction System Pacing Registry.

BACKGROUND: Left bundle branch area pacing (LBBAP) has been shown to be a feasible option for patients requiring ventricular pacing. OBJECTIVE: The purpose of this study was to compare clinical outcomes between LBBAP and RVP among patients undergoing pacemaker implantation METHODS: This observational registry included patients who underwent pacemaker implantations with LBBAP or RVP for bradycardia indications between April 2018 and October 2020. The primary composite outcome included all-cause mortality, heart failure hospitalization (HFH), or upgrade to biventricular pacing. Secondary outcomes included the composite endpoint among patients with a prespecified burden of ventricular pacing and individual outcomes. RESULTS: A total of 703 patients met inclusion criteria (321 LBBAP and 382 RVP). QRS duration during LBBAP was similar to baseline (121 ± 23 ms vs 117 ± 30 ms; P = .302) and was narrower compared to RVP (121 ± 23 ms vs 156 ± 27 ms; P <.001). The primary composite outcome was significantly lower with LBBAP (10.0%) compared to RVP (23.3%) (hazard ratio [HR] 0.46; 95%T confidence interval [CI] 0.306-0.695; P <.001). Among patients with ventricular pacing burden >20%, LBBAP was associated with significant reduction in the primary outcome compared to RVP (8.4% vs 26.1%; HR 0.32; 95% CI 0.187-0.540; P <.001). LBBAP was also associated with significant reduction in mortality (7.8% vs 15%; HR 0.59; P = .03) and HFH (3.7% vs 10.5%; HR 0.38; P = .004). CONCLUSION: LBBAP resulted in improved clinical outcomes compared to RVP. Higher burden of ventricular pacing (>20%) was the primary driver of these outcome differences.

Coronary Venous Visualization During Deep Septal Lead Placement: An Unexpected Finding.

Left bundle branch area pacing has emerged as a safe and feasible alternative to conventional pacing. Acute septal injury, septal perforation, and arteriovenous fistula are potential risks of deep septal implants. Contrast drainage through the lesser cardiac veins and subsequent filling of major epicardial vessels may be benign observations noted during forceful hand injection. (Level of Difficulty: Advanced.).

Rare case of asymptomatic spontaneous coronary artery dissection.

We present a case of a 46-year-old woman who presented to the emergency room after a syncopal episode. Most of her initial workup did not lead to any diagnosis. However, the transthoracic echocardiogram showed new onset left ventricular dysfunction. Further, cardiac evaluation showed a chronic coronary artery dissection in the proximal left anterior descending artery. Syncope was related to vasovagal event but rapid plasma reagin being positive led to the question of whether the coronary artery dissection was secondary to vasculitic manifestation of prior syphilis infection. More research is needed to answer this question and to find such an association. .

Clinical applications and prognostic implications of strain and strain rate imaging.

Strain and strain rate imaging (also known as deformation imaging) are techniques used to measure myocardial deformation. These newer echocardiographic modalities overcome the limitations of conventional echocardiography and provide a sensitive means of objectively quantifying regional and global myocardial function. It has enabled us to better understand regional myocardial function and risk stratify patients with coronary artery disease, cardiomyopathies and valvular heart disease. Also, they have been used to assess left ventricular dyssynchrony, predict responders and optimize cardiac resynchronization therapy. However, the lack of standardization and inter-vendor variability in measurements are major roadblocks to using deformation imaging in routine clinical practice. This article discusses the fundamental concept of deformation, in particular relating to strain and strain rate imaging using speckle tracking imaging and tissue Doppler imaging, the clinical applications and its prognostic implications.

Noninvasive measurement and clinical relevance of myocardial twist and torsion.

Left ventricular (LV) torsion (twisting) and untwisting results in equalization of wall stress and augmentation of pressure generated for a given shortening of sarcomere during the systolic contraction and aids early diastolic relaxation. This is attributed to the dynamic interaction of epicardial and endocardial helical myocardial fibers. Recent advances in noninvasive imaging techniques have enabled us to quantify torsion accurately and reliably in health and disease. LV torsional mechanics are altered in range of clinical conditions from those that cause minimal cardiac architectural changes as seen in hypertension, diabetes mellitus or older age to advanced cardiac remodeling as seen dilated or hypertrophic cardiomyopathy. Therefore, assessment of LV rotational mechanics may be a potentially sensitive marker of cardiac dysfunction and may provide important insights into the pathophysiology of heart failure.