Background Studies of patients presenting for catheter ablation suggest that premature ventricular contractions (PVCs) are a modifiable risk factor for congestive heart failure (CHF). The relationship between PVC frequency, incident CHF, and mortality in the general population remains unknown. Objectives The goal of this study was to determine whether PVC frequency ascertained using a 24-h Holter monitor is a predictor of LVEF decline, incident CHF, and death in a population-based cohort. Methods We studied the 1,139 Cardiovascular Health Study (CHS) participants randomly assigned to 24-h ambulatory electrocardiography (Holter) monitoring with a normal left ventricular ejection fraction (LVEF) and no history of CHF. PVC frequency was quantified using Holter studies, and LVEF was measured from baseline and 5-year echocardiograms. Participants were followed for incident CHF and death. Results Those in the upper quartile versus the lowest quartile of PVC frequency had a multivariable adjusted 3-fold greater odds of a 5-year LVEF decline (OR: 3.10, 95% CI: 1.42 to 6.77, p = 0.005), and, over a median follow-up >13 years, a 48% increased risk of incident CHF (HR: 1.48, 95% CI: 1.08 to 2.04, p = 0.02), and a 31% increased risk of death (HR: 1.31, 95% CI: 1.06 to 1.63, p = 0.01). Similar statistically significant results were observed for PVCs analyzed as a continuous variable. The specificity for the 15-year risk of CHF exceeded 90% when PVCs comprised at least 0.7% of ventricular beats. The population-level risk for incident CHF attributed to PVCs was 8.1% (95% CI: 1.2 to14.9%). Conclusions In a population-based sample, a higher frequency of PVCs was associated with LVEF decline, increased incident CHF, and increased mortality. Given the capacity to prevent PVCs through medical or ablation therapy, PVCs may represent a modifiable risk factor for CHF and death.

Background Atrial fibrillation (AF) prediction models have unclear clinical utility given the absence of AF prevention therapies and the immutability of many risk factors. Premature atrial contractions (PACs) play a critical role in AF pathogenesis and may be modifiable. Objective To investigate whether PAC count improves model performance for AF risk. Design Prospective cohort study. Setting 4 U.S. communities. Patients A random subset of 1260 adults without prevalent AF enrolled in the Cardiovascular Health Study between 1989 and 1990. Measurements The PAC count was quantified by 24-hour electrocardiography. Participants were followed for the diagnosis of incident AF or death. The Framingham AF risk algorithm was used as the comparator prediction model. Results In adjusted analyses, doubling the hourly PAC count was associated with a significant increase in AF risk (hazard ratio, 1.17 [95% CI, 1.13 to 1.22]; P < 0.001) and overall mortality (hazard ratio, 1.06 [CI, 1.03 to 1.09]; P < 0.001). Compared with the Framingham model, PAC count alone resulted in similar AF risk discrimination at 5 and 10 years of follow-up and superior risk discrimination at 15 years. The addition of PAC count to the Framingham model resulted in significant 10-year AF risk discrimination improvement (c-statistic, 0.65 vs. 0.72; P < 0.001), net reclassification improvement (23.2% [CI, 12.8% to 33.6%]; P < 0.001), and integrated discrimination improvement (5.6% [CI, 4.2% to 7.0%]; P < 0.001). The specificity for predicting AF at 15 years exceeded 90% for PAC counts more than 32 beats/h. Limitation This study does not establish a causal link between PACs and AF. Conclusion The addition of PAC count to a validated AF risk algorithm provides superior AF risk discrimination and significantly improves risk reclassification. Further study is needed to determine whether PAC modification can prospectively reduce AF risk. Primary Funding Source American Heart Association, Joseph Drown Foundation, and National Institutes of Health.

BACKGROUND Abnormal atrial repolarization is important in the development of atrial fibrillation (AF), but no direct measurement is available in clinical medicine. OBJECTIVE To determine whether the QT interval, a marker of ventricular repolarization, could be used to predict incident AF. METHODS We examined a prolonged QT corrected by the Framingham formula (QTFram) as a predictor of incident AF in the Atherosclerosis Risk in Communities (ARIC) study. The Cardiovascular Health Study (CHS) and Health, Aging, and Body Composition (Health ABC) study were used for validation. Secondary predictors included QT duration as a continuous variable, a short QT interval, and QT intervals corrected by other formulae. RESULTS Among 14,538 ARIC participants, a prolonged QTFram predicted a roughly two-fold increased risk of AF (hazard ratio [HR] 2.05, 95% confidence interval [CI] 1.42–2.96, p<0.001). No substantive attenuation was observed after adjustment for age, race, sex, study center, body mass index, hypertension, diabetes, coronary disease, and heart failure. The findings were validated in CHS and Health ABC and were similar across various QT correction methods. Also in ARIC, each 10-ms increase in QTFram was associated with an increased unadjusted (HR 1.14, 95%CI 1.10–1.17, p<0.001) and adjusted (HR 1.11, 95%CI 1.07–1.14, p<0.001) risk of AF. Findings regarding a short QT were inconsistent across cohorts. CONCLUSIONS A prolonged QT interval is associated with an increased risk of incident AF.

BackgroundTransseptal puncture is a critical step in achieving left atrial (LA) access for a variety of cardiac procedures. Although the mechanical Brockenbrough needle has historically been used for this procedure, a needle employing radiofrequency (RF) energy has more recently been approved for clinical use. We sought to investigate the comparative effectiveness of an RF versus conventional needle for transseptal LA access.Methods and ResultsIn this prospective, single‐blinded, controlled trial, 72 patients were randomized in a 1:1 fashion to an RF versus conventional (BRK‐1) transseptal needle. In an intention‐to‐treat analysis, the primary outcome was time required for transseptal LA access. Secondary outcomes included failure of the assigned needle, visible plastic dilator shavings from needle introduction, and any procedural complication. The median transseptal puncture time was 68% shorter using the RF needle compared with the conventional needle (2.3 minutes [interquartile range {IQR}, 1.7 to 3.8 minutes] versus 7.3 minutes [IQR, 2.7 to 14.1 minutes], P=0.005). Failure to achieve transseptal LA access with the assigned needle was less common using the RF versus conventional needle (0/36 [0%] versus 10/36 [27.8%], P<0.001). Plastic shavings were grossly visible after needle advancement through the dilator and sheath in 0 (0%) RF needle cases and 12 (33.3%) conventional needle cases (P<0.001). There were no differences in procedural complications (1/36 [2.8%] versus 1/36 [2.8%]).ConclusionsUse of an RF needle resulted in shorter time to transseptal LA access, less failure in achieving transseptal LA access, and fewer visible plastic shavings.Clinical Trial RegistrationURL: http://www.clinicaltrials.gov. Unique identifier: NCT01209260.

Alcohol and vagal activity may be important triggers for paroxysmal atrial fibrillation (PAF), but it remains unknown if these associations occur more often than would be expected by chance alone due to the lack of a comparator group in previous studies. We compared the self-reported frequency of these triggers in PAF patients to those with other supraventricular tachycardias (SVT). Consecutive consenting patients presenting for electrophysiology procedures at a single University Medical Center underwent a structured interview regarding arrhythmia triggers. Two hundred and twenty three patients with a documented arrhythmia (133 with PAF and 90 with SVT) completed the survey. After multivariable adjustment, PAF patients had a 4.42 greater odds (95% CI 1.35–14.44) of reporting alcohol consumption (p=0.014) and a 2.02 greater odds (95% CI 1.02–4.00) of reporting vagal activity (p=0.044) as an arrhythmia trigger compared to SVT patients. Among PAF patients, drinking primarily beer was associated with alcohol as a trigger (odds ratio [OR] 4.49, 95% CI 1.41–14.28, p=0.011), while younger age (OR 0.68, 95% CI 0.49–0.95, p=0.022) and a family history of atrial fibrillation (AF) (OR 5.73, 95% CI 1.21–27.23, p=0.028) were each independently associated with having vagal activity provoke an episode. PAF patients with alcohol triggers were more likely to have vagal triggers (OR 10.32, 95% CI 1.05–101.42, p=0.045). In conclusion, alcohol consumption and vagal activity elicit PAF significantly more often than SVT. Alcohol and vagal triggers often were found in the same PAF patients, raising the possibility that alcohol may precipitate AF via vagal mechanisms.