Association between elevated blood glucose level and non-valvular atrial fibrillation: a report from the Guangzhou heart study.

BACKGROUND: To estimate the prevalence of elevated blood glucose level (EBG, including type 2 diabetes mellitus and impaired fasting glucose), and its association with non-valvular atrial fibrillation (NVAF) in Guangzhou, China. METHODS: The population-based follow-up Guangzhou Heart Study collected baseline data from July 2015 to August 2017 among 12,013 permanent residents aged > 35 from 4 Guangzhou districts. Two streets (Dadong and Baiyun) in the Yuexiu District, and one street (Xiaoguwei) and two towns (Xinzao and Nancun) in the Panyu District were chosen as representative of urban and rural areas, respectively. Each participant completed a comprehensive questionnaire, and underwent physical examination, blood sample collection for laboratory testing, electrocardiography, and other evaluations. Multivariable logistic regression analyses were used to estimate the independent association between hyperglycemia and NVAF prevalence. RESULTS: The prevalence of EBG in overall study population was 29.9%. Compared with residents without EBG, the odds ratio (OR) for AF among residents with EBG was significantly higher (1.94, 95% confidence interval [CI]: 1.40-2.70, P <  0.001), even after multivariate adjustment for metabolic abnormalities (OR = 1.60, 95% CI: 1.14-2.25, P = 0.007), and driven by women (OR = 1.80, 95% CI: 1.12-2.91, P = 0.016). CONCLUSIONS: In Guangzhou, China, prevalence of EBG is high among residents aged > 35 years and associated with a multivariate adjusted increase in prevalence of NVAF overall and in women.

A new electrophysiologic observation in patients with idiopathic left ventricular tachycardia.

BACKGROUND: In patients with idiopathic left ventricular tachycardia (ILVT), the arrhythmogenic substrate is poorly understood. OBJECTIVE: The purpose of this study was to elucidate the ILVT characteristics and outcome of radiofrequency catheter ablation in patients with ILVT. METHODS: Twenty-four patients with ILVT and 15 patients with left accessory pathways (control) underwent high-density mapping of the left His-Purkinje system during sinus rhythm (SR) using 3-dimensional electroanatomic mapping. RESULTS: Fragmented antegrade Purkinje potential (FAP) was represented at the left ventricular septum slightly inferoposterior to the left posterior fascicle (LPF) in 23 patients with ILVT. In control subjects, no FAPs could be recorded at the same region, FAPs were identified at the proximal portion of the LPF (4 patients) and at the distal LPF (1 patient). The finding of any FAPs in ILVT patients was significantly higher than that in control patients (23/24 vs 5/15, P < .01). Radiofrequency ablation at the area of FAP resulted in successful ablation in 23 patients with ILVT. No ILVT recurred during follow-up of 16.3 ± 7.2 months. CONCLUSION: In patients with ILVT, FAP located at the left ventricular septum slightly inferoposterior to the LPF is a novel finding using 3-dimensional electroanatomic mapping. The FAP may represent an arrhythmogenic substrate in ILVT and may be used for guiding successful ablation.

The characteristics of verapamil-sensitive idiopathic left ventricular tachycardia combined with a left accessory pathway and the effect of radiofrequency catheter ablation.

AIMS: Verapamil-sensitive idiopathic left ventricular tachycardia (ILVT) combined with a left accessory pathway (AP) is a relatively rare condition. This study examines the characteristics of patients with this condition and the effect of radiofrequency catheter ablation (RFCA). METHODS AND RESULTS: Catheter ablation was performed on 140 ILVT patients at a single centre from January 2004 to December 2009. A concealed left AP was found in seven patients (5%), all of whom were male, with an average age of 21 ± 9 years. Sustained ILVT and orthodromic atrioventricular reentrant tachycardia (AVRT) were induced in all seven patients. Retrograde activation through a bystander AP occurred concomitantly with ILVT, with an average tachycardia length of 346 ± 29 ms (range 310-400 ms). The location of the APs in four patients was left posterior, two of which showed a slow and decremental property, while in three it was left lateral. Ablation via a retrograde transaortic approach was performed in the seven patients. The left AP was ablated first in six patients, but ILVT was no longer induced in one and became non-sustained in another. In the seventh patient, ILVT was ablated first and this proved successful. CONCLUSIONS: Among patients with IVLT, 5% had a concomitant left AP, most of who were young men. The location of the left AP was mainly posterior and lateral, with 30% showing a slow and decremental property. Idiopathic left ventricular tachycardia and AP should be ablated simultaneously.

Focal atrial tachycardia originating from the distal portion of the left atrial appendage: characteristics and long-term outcomes of radiofrequency ablation.

AIMS: The characteristics and response to ablation therapy of focal atrial tachycardia (AT) originating from the distal portion of left atrial appendage (LAAd) are still not quite clear up to now. The goal of this study is to characterize electrocardiographic and electrophysiological features and radiofrequency ablation (RFA) outcomes in patients with focal AT originating from the LAAd. METHODS AND RESULTS: Fourteen patients (2.1%) (mean age, 25 ± 10 years; nine women; mean symptom duration, 5 ± 5 years) undergoing RFA of focal AT originating from the LAAd were included out of 668 RFA patients. Activation mapping was performed. P waves were classified as negative, positive, isoelectric, or biphasic. Tachycardia that was incessant in all, demonstrated a characteristic P-wave morphology and endocardial activation pattern: P wave was negative in leads I and aVL, highly positive in the inferior leads, and broad and positive in lead V1. Radiofrequency ablation was acutely successful in 13 of 14 patients. The endocardial activation time of the successful RFA sites was 47.1 ± 4.3 ms before the onset of P wave. There were no complications in any of the 14 patients and long-term success was achieved in 13 of 13 successful RFA patients during follow-up (5 ± 2 years). CONCLUSION: The LAAd is an uncommon site of origin for focal AT (2.1% incidence). In this case series, focal ATs originating from the LAAd had typical electrophysiological and electrocardiographic characteristics. Focal ablation yielded high acute success rate with low rate of recurrence during follow-up.

Is selective ipsilateral PV isolation sufficient for focally triggered paroxysmal atrial fibrillation? Comparison of selective ipsilateral pulmonary vein isolation versus bilateral pulmonary vein isolation.

INTRODUCTION: Selective ipsilateral pulmonary vein isolation (SIPVI) has shown comparable efficacy in focal triggered atrial fibrillation (AF) versus isolation of all pulmonary veins (PVs), yet the sufficiency for such an ablation strategy to all patients is unclear. This study sought to identify a subgroup of patients for SIPVI and a subgroup of patients for bilateral PV isolation (BiPVI) with long-term success by comparing the clinical efficacy of SIPVI and BiPVI on PV-triggered AF. METHODS AND RESULTS: One hundred and forty-two patients (106 males; mean age 51 ± 13 years) with focal PV triggered paroxysmal AF (PAF) were studied. Seventy patients underwent SIPVI and 72 patients underwent BiPVI. After the first ablation, 44 patients (44/70) in the SIPVI group and 54 patients (54/72) in the BiPVI group were free of AF without antiarrhythmic drugs, after a follow-up period of 36 ± 12 months (log-rank test P = 0.1594). In patients younger than 50 years of age with a left atrium (LA) diameter <40 mm, SIPVI had a high success rate (15/18, 83%) of freedom from AF. However, for patients aged ≥50 years with an LA diameter ≥40 mm, 10 of the 12 patients in the SIPVI group and only 5 of the 15 patients in the BiPVI group had a recurrence of AF (log-rank test P = 0.0173). CONCLUSIONS: For focally triggered PAF, in patients aged <50 years with an LA diameter <40 mm, SIPVI of triggering PV had a high success rate of freedom from AF. However, in patients aged ≥50 years with an LA diameter ≥40 mm, BiPVI achieved a higher success rate.