Left Ventricular Hypertension And Influential Factors Of Low Voltage Region In Paroxysmal Atrial Fibrillation

Section I Left Atrial Low Voltage Zone:Prevalence, Distribution and its Impact on Ablation Outcome of Paroxysmal Atrial FibrillationBackground The prevalence, distribution of low voltage zone (LVZ), and its impact on ablation outcome in patients with paroxysmal atrial fibrillation (PAF) remains unclear.Methods A total of 122 patients (age 55.4±9.4 years; 73.8% males) with PAF who underwent fisrt-time circumferential pulmonary vein isolation (CPVI) from September 2012 to April 2014 were studied. Before ablation, extensive voltage mapping of the left atrium (LA) was performed under sinus rhythm. Low voltage zones (LVZs) were semi-quantitatively estimated and presented as low voltage index (LVI). Follow-up for AF recurrence≥ 12 months was performed. Univariate and multivariate analyses were performed to assess the predictive value of LVZ and other variables on ablation outcome.Results In total, LVZs were observed in 44 patients (36.1%). The LA roof, and the lateral, anterior wall were most often affected. Multivariate analysis showed that AF duration independently predicted the presence of LVZ (OR 1.009; 95% CI 1.002-1.017; P = 0.004). During mean follow-up of 20.9±5.9 months,40 patients (35.1%) experienced AF recurrence. The success rate was 83.6% for patients without LVZ and 33.3% for patients with LVZ (P< 0.001). Multivariate analysis showed that LVI was an independent predictor of AF recurrence (HR 5.238; 95% CI 2.624-10.453; P< 0.001).Conclusions Totally,36.1% of PAF patients were observed with LA LVZ, who had a longer AF duration. Furthermore, LVI in patients undergoing CPVI for PAF is a powerful, independent predictor of procedural failure.Section II The Impact of Alcohol Consumption on Substrate Remodeling and Ablation Outcome of Paroxysmal Atrial FibrillationBackground The effect of alcohol consumption on substrate remodeling and ablation outcome of paroxysmal atrial fibrillation (PAF) remains unknown.Methods We performed circumferential pulmonary vein isolation (CPVI) and voltage mapping of left atrium (LA) during sinus rhythm in 122 patients with symptomatic PAF (age 55.4±9.4 years,73.8% men) from September 2012 to April 2014. Low voltage zones (LVZs) were semi-quantitatively estimated and presented as low voltage index (LVI). Each patient’s daily alcohol consumption history was recorded at baseline and classified into alcohol abstainers, moderate drinkers, and heavy drinkers based on the National Institute on Alcohol Abuse and Alcoholism definition. Follow-up was≥ 12 months for AF recurrence.Results Alcohol abstainers, moderate, and heavy drinkers were 70 (57.4%),13 (10.6%), and 39 (32.0%), respectively. In total, LVZs were observed in 44 patients (36.1%). Daily alcohol consumption independently predicted presence of LVZs (OR, 1.097,95% CI [1.001-1.203], P= 0.047). During mean follow-up of 20.9±5.9 months, 40 patients (35.1%) experienced AF recurrence. Success rate was 81.3%,69.2%, and 35.1% in alcohol abstainers, moderate drinkers, and heavy drinkers, respectively (overall log rank p< 0.001). Multivariate analysis showed both alcohol consumption and LVI were independent predictors of AF recurrence (HR,1.579,95% CI [1.085-2.298], P= 0.017; HR,2.188,95% CI [1.582-3.026], P<0.001, respectively). Furthermore, mediation analysis revealed that LVZs acted as a partial mediator in effect of alcohol consumption on AF ablation outcomes.Conclusions Daily alcohol consumption was associated with atrial remodeling and heavy drinkers have substantial risk for AF recurrence after CPVI.Section Ⅲ Functional Mitral Regurgitation:Predictor for Atrial Substrate Remodeling and Poor Ablation Outcome in Paroxysmal Atrial FibrillationBackground Functional mitral regurgitation (FMR) is not uncommon in atrial fibrillation (AF) patients. We sought to investigate the association between FMR and atrial substrate remodeling as well as the ablation outcome in paroxysmal AF (PAF) patients.Methods We retrospectively analyzed a cohort of 132 patients (age 55.1 ± 9.6 years, 75.8% male) with symptomatic PAF who underwent initial ablation in our institute. FMR was defined as regurgitation jet area to left atrium (LA) area ratio ≥ 0.1 without any primary valvular disease. Voltage mapping of LA was performed under sinus rhythm. Low voltage zones (LVZs) were semi-quantitatively estimated and presented as low voltage index. Follow-up for AF recurrence ≥ 12 months was performed.Results In total,40 patients (29.6%) were detected with FMR, who were older than the non-FMR patients (P = 0.007) and had larger LA diameters (P = 0.02). LA LVZs were observed in 64.9% of patients with FMR versus 22.1% patients without FMR (P < 0.001). FMR independently predicted the presence of LVZs (OR 7.286; 95% CI, 3.023-17.562; P< 0.001). During a mean follow-up of 22.9±6.5 months,38 patients (28.8%) experienced AF recurrence. The recurrence rate was 60.0% and 19.5% in FMR and non-FMR cohort, respectively (log rank P< 0.001). Multivariate analysis showed that FMR was an independent predictor for AF recurrence (HR,2.291,95% CI [1.062-4.942], P = 0.03).Conclusions FMR was strongly associated with atrial substrate remodeling. Furthermore, patients with FMR have substantial risk for AF recurrence post-ablation.