Patterns and Characteristics of SKYLINE-Lumipoint Feature in the Catheter Ablation of Atypical Atrial Flutter: Insight from a Novel Lumipoint Module of Rhythmia Mapping System.

Background: Atypical atrial flutter (aAFL) is not uncommon, especially after a prior cardiac surgery or extensive ablation in atrial fibrillation (AF). Aims: To revisit aAFL, we used a novel Lumipoint algorithm in the Rhythmia mapping system to evaluate tachycardia circuit by the patterns of global activation histogram (GAH, SKYLINE) in assisting aAFL ablation. Methods: Fifteen patients presenting with 20 different incessant aAFL, including two naïve, six with a prior AF ablation, and seven with prior cardiac surgery were studied. Results: Reentry aAFL in SKYLINE typically was a multi-deflected peak with 1.5 GAH-valleys. Valleys were sharp and narrow-based. Most reentry aAFL (18/20, 90%) lacked a plateau and displayed a steep GAH-valley with 2 GAH-valleys per tachycardia. Each GAH-valley highlighted 1.9 areas in the map. Successful sites of ablation all matched one of the highlighted areas based on GAH-valleys < 0.4. These sites corresponded with the areas highlighted by GAH-score < 0.4 in reentry aAFL, and by GAH-score < 0.2 in localized-reentry aAFL. Conclusions: The present study showed benefits of the LumipointTM module applied to the RhythmiaTM mapping system. The results were the efficient detection of the slow conduction, better identification of ablation sites, and fast termination of the aAFL with favorable outcomes.

Prediction of Recurrent Atrial Tachyarrhythmia After Receiving Atrial Flutter Ablation in Patients With Prior Cardiac Surgery for Valvular Heart Disease.

Background: Surgical scars cause an intra-atrial conduction delay and anatomical obstacles that facilitate the perpetuation of atrial flutter (AFL). This study aimed to investigate the outcome and predictor of recurrent atrial tachyarrhythmia after catheter ablation in patients with prior cardiac surgery for valvular heart disease (VHD) who presented with AFL. Methods: Seventy-two patients with prior cardiac surgery for VHD who underwent AFL ablation were included. The patients were categorized into a typical AFL group (n = 45) and an atypical AFL group (n = 27). The endpoint was the recurrence of atrial tachyarrhythmia during follow-up. A multivariate analysis was performed to determine the predictor of recurrence. Results: No significant difference was found in the recurrence rate of atrial tachyarrhythmia between the two groups. Patients with concomitant atrial fibrillation (AF) had a higher recurrence of typical AFL compared with those without AF (13 vs. 0%, P = 0.012). In subgroup analysis, typical AFL patients with concomitant AF had a higher incidence of recurrent atrial tachyarrhythmia than those without it (53 vs. 14%, P = 0.006). Regarding patients without AF, the typical AFL group had a lower recurrence rate of atrial tachyarrhythmia than the atypical AFL group (14 vs. 40%, P = 0.043). Multivariate analysis showed that chronic kidney disease (CKD) and left atrial diameter (LAD) were independent predictors of recurrence. Conclusions: In our study cohort, concomitant AF was associated with recurrence of atrial tachyarrhythmia. CKD and LAD independently predicted recurrence after AFL ablation in patients who have undergone cardiac surgery for VHD.

The presence of ectopic atrial rhythm predicts adverse cardiovascular outcomes in a large hospital-based population.

BACKGROUND: Whether ectopic atrial rhythm (EAR) is a high-risk cardiovascular phenotype (eg, the manifestation of a diseased sinoatrial node) or just a benign accelerated ectopic pacemaker remains unclear. OBJECTIVE: We aimed to analyze the cardiovascular outcomes and underlying mechanisms in patients with EAR. METHODS: From a 12-lead electrocardiogram hospital-based electrocardiogram database, a total of 2896 adults with EAR were propensity score matched at 1:5 with 14,480 patients with sinus rhythm (SR). Patients were retrospectively followed up for cardiovascular mortality (the primary outcome) and permanent pacemaker implantation (the secondary outcome). Heart rate variability was analyzed to compare autonomic function between patients with EAR and those with SR. RESULTS: The prevalence of EAR was 1.13%, which increased with age. Compared with the matched patients, those with EAR had a higher risk of cardiovascular mortality (adjusted hazard ratio 1.93; 95% confidence interval 1.52-2.44; P < .0001) and permanent pacemaker implantation (adjusted hazard ratio 5.94; 95% confidence interval 3.89-9.09; P < .0001) according to the Cox proportional hazards regression model. The risk of cardiovascular mortality was similar across the subgroups on the basis of age, sex, hypertension, type 2 diabetes mellitus, congestive heart failure, myocardial infarction, stroke, and chronic kidney diseases. In patients with EAR, the low frequency/high frequency and standard deviation of the mean normal-to-normal intervals/root mean square of successive RR interval differences ratios for heart rate variability were both lower than those in patients with SR. This implied autonomic imbalance in patients with EAR. CONCLUSION: Patients with EAR have a higher risk of cardiovascular mortality and permanent pacemaker implantation, which was associated with autonomic imbalance.

The Impact of Estrogen Supplementation to Autonomic and Sleep Modulations in Free-Moving Spontaneously Hypertensive Rats.

Sleep and estrogen levels have an impact on neural regulation and are associated with cardiovascular (CV) events. We investigated the effects of estrogen on heart rate variability (HRV) and circadian cycle in spontaneously hypertensive rats (SHRs). Polysomnographic recording was performed in seven male and seven female SHRs during sleep. The electroencephalogram (EEG) and electromyogram (EMG) were evaluated to define active waking (AW), quiet sleep (QS), and paradoxical sleep (PS) stages. Cardiac activities were measured by RR interval of the electrocardiogram (ECG), mean arterial pressure (MAP), and power spectrum of HRV.In ECG, estrogen prolonged the RR interval in total sleep when compared with that at baseline in male SHRs (203.74 ± 6.61 versus 181.30 ± 8.06 ms, P < 0.001) and in female SHRs (169.21 ± 6.43 versus 160.76 ± 10.66 ms, P < 0.05). In HRV, the estrogen increased the high frequency (HF) in total sleep when compared with that at baseline in male SHRs (1.03 ± 0.28 versus 0.60 ± 0.43 ln (ms2), P < 0.001) and in female SHRs (0.71 ± 0.26 versus 0.42 ± 0.19 ln (ms2), P < 0.05).In male SHRs, estrogen increased the frequency of QS (26.50 ± 4.85 versus 20.79 ± 5.07, P < 0.01) and PS (25.64 ± 5.18 versus 20.14 ± 4.75, P < 0.05) stages when compared with baseline. In female SHRs, estrogen increased the percentage of delta waves in total sleep (79.87% ± 3.10% versus 76.71% ± 2.74%, P < 0.05) when compared with that at baseline.In HRV, estrogen leads to neuromodulation by increased parasympathetic tone in all SHRs, suggesting a lower risk to CV events. In sleep analyses, estrogen in male SHRs caused poor sleep quality. In contrast, estrogen in female SHRs demonstrated improved quality of sleep and decreased risk of hypertension.