Heart rhythm最新文献

Background: Pulsed field ablation (PFA) near coronary arteries has been associated with acute vasospasm, primarily linked to electric field intensity. However, the impact of other waveform characteristics, such as pulse number, has not been studied and could have physiopathological implications.

Objectives: This study aimed to compare a clinically relevant full PFA waveform against a single-pulse configuration to evaluate differences in vasospasm incidence, severity, recovery kinetics, and associated histological changes.

Methods: Eight anesthetized pigs underwent epicardial PFA directly over the left anterior descending artery (LAD) using two protocols: a full waveform (2 kV, 450 pulses) and a single-pulse waveform (2 kV, 1 pulse). Coronary angiography was performed before, immediately after, and every 5 minutes until spasm recovery or 20 min. Animals were euthanized > 2 hours post-ablation for histological analysis.

Results: Thirty-seven ablations were performed (23 full, 14 single-pulse). Acute vasospasm occurred in all cases (100%). Mean luminal stenosis was similar between groups (full vs. single-pulse: 59 ± 10% vs. 68 ± 10%, p=ns). Lesion depth was greater with full pulses (7.5 ± 1.8 mm vs. 3.4 ± 0.8 mm, p<0.0001). Histology revealed comparable patterns of internal elastic lamina disruption across both groups.

Conclusions: Coronary vasospasm, while highly dependent on electric field intensity, exhibited little sensitivity to pulse number, occurring even after a single pulse. This suggests that vasospasm is primarily triggered by field strength rather than by the cumulative energy parameters required for lesion formation. Furthermore, the observation of acute intimal injury suggests that the intima may play a central role in the pathophysiology of PFA-induced vasospasm.

Background: His bundle pacing (HBP) provides physiological ventricular activation by engaging the native His-Purkinje system. Although mid-term safety and efficacy are established, long-term outcomes beyond 5 years remain insufficiently defined.

Objective: To evaluate long-term performance, device behavior, and clinical outcomes of permanent HBP over follow-up up to 10 years.

Methods: We retrospectively analyzed 500 consecutive patients who underwent successful HBP between 2003 and 2013 at two high-volume centers. Clinical, device, and echocardiographic data were collected at scheduled in-person and remote evaluations. Outcomes included pacing thresholds, sensing, lead-related events, device longevity, left ventricular ejection fraction (LVEF), hospitalizations, and mortality. Time-to-event analyses were performed using Kaplan-Meier estimates and Cox regression.

Results: Follow-up data were available for 487 patients (mean age 75 ± 9years) with a mean duration of 7.9 ± 4.7 years; 193 patients completed ≥10 years of follow up. Selective HBP was achieved in 51%. Lead-related events occurred in 12.1% of patients, most commonly capture threshold rise (10.5%); lead dislodgment was rare (0.8%). Battery depletion occurred in 66.6% at 10 years. Backup leads were associated with reduced device longevity (HR 1.87; p<0.001). Overall, LVEF remained stable; 30.7% showed ≥5% improvement in LVEF, particularly among those with baseline LVEF <45%. All-cause mortality was 38.2%, predominantly non-cardiac.

Conclusions: This large multicenter experience demonstrates that HBP is a safe and effective pacing strategy with durable performance, acceptable device longevity, and stable ventricular function over a decade of follow-up. Technical issues-primarily threshold rise-are generally manageable. These findings provide the longest longitudinal data to date supporting HBP as a reliable physiologic pacing modality.

Previous case studies have reported bradycardia-dependent augmentation of J waves in patients with idiopathic ventricular fibrillation (VF). However, the response patterns of J waves to changing heart rates have rarely been evaluated in the general population. In this review, the response patterns of J waves to changing RR intervals were studied in the general population during premature beats or pacing and compared with those of J waves in idiopathic VFs and the mechanism and clinical importance of J waves are discussed. J waves associated with idiopathic VFs showed bradycardia-dependent augmentation and tachycardia-dependent attenuation, whereas J waves unrelated to idiopathic VFs exhibited tachycardia-dependent augmentation and less obvious bradycardia-dependent attenuation. These different response patterns suggest the presence of different mechanisms-repolarization-dependent and depolarization-dependent mechanisms-and can be used for risk stratification and selection of therapeutic options.

Background: Catheter ablation of atrial fibrillation (AF) is primarily performed at tertiary hospitals (THs). The safety and effectiveness of AF ablation at community hospitals (CHs) remains unclear.

Objective: To assess the long-term efficacy and safety of paroxysmal AF (PAF) ablation at CHs.

Methods: We retrospectively analyzed patients evaluated at 2 CHs who underwent zero-fluoroscopy (ZF) pulmonary vein isolation (PVI) at a TH (2015 - 2017) with those ablated at CHs (2017-2021) after implementation of a local ablation program. Patients were followed up for 24 months (m) with event monitors and self-wearable cardiac monitoring devices. Propensity score matching (PSM) yielded two matched cohorts of 290 patients (mean age 66 ± 5 years; 70% male; CHA₂DS₂-VASc score 1 ± 2; EF 55%).

Results: No intraprocedural complications or transfers occurred. CH patients had lower AF recurrence at 12 and 18 m (17% vs. 29%, p<0.010; 23% vs. 42%, p<0.05), shorter diagnosis-to-ablation time (DAB) (6.1± 1.2 m vs. 12.4± 2.5 m, p<0.01), and higher same-day discharge rates (93% vs. 70%, p<0.010). AF recurrence was similar at 24 months (20%), but repeat ablation was higher in TH patients (27% vs. 7%, p<0.01). Longer DAB predicted AF recurrence at 18 m (HR 2.63; 95% CI, 1.65-4.21), with greater risk for DAB= 6-9 m (HR 3.13; 95% CI, 2.136-3.13) and DAB>9 m (HR 3.7; 95% CI, 2.30-3.75) compared with <3 m.

Conclusions: Ablation of PAF at CHs with ZF is safe with a shorter DAB and decrease AF recurrences when compared with TH.

Background: Prospective studies with a focus on the safety and effectiveness profile of stylet-driven left bundle branch area pacing (LBBAP) leads at both implant and chronic stages significantly contribute to a comprehensive perspective of utilizing SDL in this pacing modality.

Objective: Prospectively evaluate the performance and safety of LBBA-placed Solia S leads and the related impact on the patient's quality of life (QOL) through 12 months.

Methods: A multi-center, prospective, non-randomized trial enrolled patients with standard pacing indications in whom a Solia S lead was implanted in the left bundle branch area (LBBA). Adverse events and quality-of-life metrics were collected out to 12 months post implant along with threshold, sensing, and lead impedance data.

Results: For the 161 patients who experienced an SADE event or had at least 335 days of follow-up, the associated 12-month serious adverse device effect (SADE) rate was 0.02 events per subject-year [SADE-free rate of 98.1% (95% CI: 94.7%, 99.6%)]. The mean threshold was 0.98V at 0.4ms (vs. 0.84V at implant), mean sensing was 12.76mV (vs. 9.15mV at implant), and mean impedance was 521.8 ohms (vs. 670.5 ohms at implant). The mean change for the QOL physical function scale was +11.4 ± 24.0 (95% CI: 7.4, 15.4; t-value = 4.23; p < 0.001).

Conclusion: These 12-month results utilizing the Solia S SDL demonstrate freedom from LBBAP lead-related complications, acceptable lead performance characteristics along with a significant coincident improvement in a patient's physical function.