Impact on clinical outcome of ventricular arrhythmias in patients undergoing transcatheter aortic valve implantation.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has become a largely used treatment for severe aortic stenosis. There are limited data, however, about predictors of long-term prognosis in this population. In this study, we assessed whether ventricular arrhythmias may predict clinical outcomes in patients undergoing TAVI. METHODS AND RESULTS: We performed a 24 h ECG Holter monitoring in 267 patients who underwent TAVI for severe aortic stenosis within 30 days from a successful procedure. The occurrence of frequent premature ventricular complexes (PVCs; ≥30/h), polymorphic PVCs and nonsustained ventricular tachycardia (NSVT) was obtained for each patient. Clinical outcome was obtained for 228 patients (85%), for an average follow-up of 3.5 years (range 1.0-8.6). Cardiovascular events (CVEs; cardiovascular death or resuscitated cardiac arrest) occurred in 26 patients (11.4%) and 63 patients died (27.6%). Frequent PVCs but not polymorphic PVCs and NSVT were found to be associated with CVEs at univariate analysis. Frequent PVCs were indeed found in 12 patients with (46.2%) and 35 without (17.3%) CVEs [hazard ratio 2.30; 95% confidence interval (CI) 1.03-5.09; P  = 0.04], whereas polymorphic PVCs were found in 11 (42.3%) and 54 (26.7%) patients of the two groups, respectively (hazard ratio 1.44; 95% CI 0.64-3.25; P  = 0.38), and NSVT in 9 (34.6%) and 43 patients of the two groups, respectively (hazard ratio 1.18; 95% CI 0.48-2.87; P  = 0.72). Frequent PVCs, however, were not significantly associated with CVEs at multivariate Cox regression analysis (hazard ratio 1.53; 95% CI 0.37-6.30; P  = 0.56). Both frequent PVCs, polymorphic PVCs and NSVT showed no significant association with mortality. CONCLUSION: In our study, the detection of frequent PVCs at Holter monitoring after TAVI was a predictor of CVEs (cardiovascular death/cardiac arrest), but this association was lost in multivariable analysis.

Ventricular arrhythmias recorded on 12-lead ambulatory electrocardiogram monitoring in healthy volunteer athletes and controls: what is common and what is not.

AIMS: Premature ventricular beats (PVBs) in athletes are often benign, but sometimes they may be a sign of an underlying disease. We evaluated the prevalence, burden, and morphology of PVBs in healthy voluntary athletes and controls with the main purpose of defining if certain PVB patterns are 'common' and 'training related' and, as such, are more likely benign. METHODS AND RESULTS: We studied 433 healthy competitive athletes [median age 27 (18-43) years, 74% males] and 261 age- and sex-matched sedentary subjects who volunteered to undergo 12-lead 24 h ambulatory electrocardiogram (ECG) monitoring (24H ECG), with a training session in athletes. Ventricular arrhythmias (VAs) were evaluated in terms of their number, complexity [i.e. couplet, triplet, or non-sustained ventricular tachycardia (NSVT)], exercise inducibility, and morphology. Eighty-six percent of athletes and controls exhibited a total of ≤10 PVBs/24 h, and >90% did not show any couplets, triplets, or runs of NSVT > 3 beats. An higher number of PVBs correlated with increasing age (P < 0.01) but not with sex and level of training. The most frequent morphologies among the 36 athletes with >50 PVBs were the infundibular (44%) and fascicular (22%) ones. In a comparison between athletes and sedentary individuals, and male and female athletes, no statistically significant differences were found in PVBs morphologies. CONCLUSION: The prevalence and complexity of VAs at 24H ECG did not differ between athletes and sedentary controls and were not related to the type and amount of sport or sex. Age was the only variable associated with an increased PVB burden. Thus, no PVB pattern in the athlete can be considered 'common' or 'training related'.

High Burden of Premature Ventricular Complex Increases the Risk of New-Onset Atrial Fibrillation.

Background High burden of premature ventricular complex (PVC) leads to increased cardiovascular mortality. A recent nationwide population-based study demonstrated that PVC is associated with an increased risk of atrial fibrillation (AF). However, the relationship between PVC burden and new-onset AF has not been investigated. The purpose of the study is to elucidate whether PVC burden is associated with new-onset AF. Methods and Results We designed a single-center, retrospective, large population-based cohort study to evaluate the role of PVC burden and new-onset AF in Taiwan. Patients who were AF naïve with PVC were divided into the low burden group (<1000/day) and moderate-to-high burden group (≥1000/day) based on the 24-h Holter ECG report. New-onset AF was defined as a new or first detectable event of either a persistent or paroxysmal AF. A total of 16 030 patients who were AF naïve and underwent 24-h Holter ECG monitoring were enrolled in this study, with a mean follow-up time of 973 days. A propensity score-matched analysis demonstrated that the moderate-to-high burden PVC group had a higher risk of developing new-onset AF than that of the low burden PVC group (4.91% versus 2.73%, P<0.001). Multivariate Cox regression analysis showed that moderate-to-high burden of PVC is an independent risk factor for new-onset AF. The Kaplan-Meier analysis demonstrated that patients with moderate-to-high PVC burden were associated with higher risk of new-onset AF (log-rank P<0.001). Conclusions PVC burden is associated with new-onset AF. Patients with moderate-to-high PVC burden are at a higher risk of new-onset AF. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03877614.

Risk factors for the development of premature ventricular complex-induced cardiomyopathy: a systematic review and meta-analysis.

BACKGROUND: Premature ventricular complexes (PVCs) are a potentially reversible cause of heart failure. However, the characteristics of patients most likely to develop impaired left ventricular function are unclear. Hence, the objective of this study is to systematically assess risk factors for the development of PVC-induced cardiomyopathy. METHODS: We performed a structured database search of the scientific literature for studies investigating risk factors for the development of PVC-induced cardiomyopathy (PVC-CM). We investigated the reporting of PVC-CM risk factors (RF) and assessed the comparative association of the different RF using random-effect meta-analysis. RESULTS: A total of 26 studies (9 prospective and 17 retrospective studies) involving 16,764,641 patients were analyzed (mean age 55 years, 58% women, mean PVC burden 17%). Eleven RF were suitable for quantitative analysis (≥ 3 occurrences in multivariable model assessing a binary change in left ventricular (LV) function). Among these, age (OR 1.02 per increase in the year of age, 95% CI [1.01, 1.02]), the presence of symptoms (OR 0.18, 95% CI [0.05, 0.64]), non-sustained ventricular tachycardias (VT) (OR 3.01, 95% CI [1.39, 6.50]), LV origin (OR 2.20, 95% CI [1.14, 4.23]), epicardial origin (OR 4.72, 95% CI [1.81, 12.34]), the presence of interpolation (OR 4.93, 95% CI [1.66, 14.69]), PVC duration (OR 1.05 per ms increase in QRS-PVC duration [1.004; 1.096]), and PVC burden (OR 1.06, 95% CI [1.04, 1.08]) were all significantly associated with PVC-CM. CONCLUSIONS: In this meta-analysis, the most consistent risk factors for PVC-CM were age, non-sustained VT, LV, epicardial origin, interpolation, and PVC burden, whereas the presence of symptoms significantly reduced the risk. These findings help tailor stringent follow-up of patients presenting with frequent PVCs and normal LV function.

Prevalence of atrial fibrillation and procedural outcome in patients undergoing catheter ablation for premature ventricular complexes.

INTRODUCTION: Atrial fibrillation (AF) and premature ventricular complexes (PVC) are common arrhythmias. We aimed to investigate AF prevalence in patients with PVC and its impact on PVC ablation outcomes. METHODS: Consecutive patients undergoing PVC ablation at a single institution between 2016 and 2019 were included and prospectively followed for 2 years. Patients with severe valvular heart disease, hyperthyroidism, malignancy, alcohol use disorder and advanced renal/hepatic diseases were excluded. Twelve-lead electrocardiograms were used to diagnose AF and assess PVC morphology. All PVCs were targeted for ablation using 4-mm irrigated-tip catheters at standardized radiofrequency power guided by 3-D mapping and intracardiac echocardiography. Patients were followed with remote monitoring, device interrogations and office visits every 6 months for 2 years. Detection of any PVCs in follow-up was considered as recurrence. RESULTS: A total of 394 patients underwent PVC ablation and 96 (24%) had concurrent AF. Patients with PVC and AF were significantly older (68.2 ± 10.8 vs. 58.3 ± 15.8 years, p < .001), had lower LV ejection fraction (43.3 ± 13.3% vs. 49.6 ± 12.4%, p < .001), higher CHA2 DS2 -VASc (2.8 ± 1.3 vs. 2.0 ± 1.3, p < .001) than those without. PVCs with ≥2 morphologies were detected in 60.4% and 13.7% patients with vs without AF (p < .001). At 2-year follow-up, PVC recurrence rate was significantly higher in patients with vs without AF (17.7% vs. 9.4%, p = .02). CONCLUSION: AF was documented in 1/4 of patients undergoing PVC ablation and was associated with lower procedural success at long-term follow-up. This was likely attributed to older age, worse LV function and higher prevalence of multiple PVC morphologies in patients with concurrent AF.

Risk of atrial fibrillation among patients with premature ventricular complexes: a systematic review and meta-analysis of cohort studies.

INTRODUCTION: Atrial fibrillation (AF) is more likely found in patients with premature ventricular complexes (PVCs). Nonetheless, the outcomes of previous investigations remain inconclusive. To evaluate the link between PVCs and the risk of AF, we did a systematic review and meta-analysis. EVIDENCE ACQUISITION: Potentially eligible studies were found by searching for published publications indexed in the MEDLINE and EMBASE databases from inception to April 13, 2021, looking for studies that assessed the risk of AF in patients with PVCs vs. those who did not have PVCs. Dersimonian and Laird's random-effect, generic inverse variance technique was used to calculate the pooled risk ratio (RR) and 95% confidence interval (CI). EVIDENCE SYNTHESIS: The meta-analysis includes 6 cohort studies (1 prospective and 5 retrospective cohort studies) with a total of 9,662,088 individuals. We found that patients with PVCs have a significantly higher risk of AF than individuals without PVCs with the pooled RR of 1.90 (95% CI: 1.51-2.39, I2=83%). CONCLUSIONS: PVCs are significantly related with a 1.90-fold higher incidence of AF, according to the present systematic review and meta-analysis. Nonetheless, further research is needed to determine how this connection should be treated in clinical practice if it is causal.

Obstetric and fetal/neonatal outcomes in pregnant women with frequent premature ventricular complexes and structurally normal heart.

BACKGROUND: High premature ventricular complex (PVC) burden may increase the risk of left ventricular dysfunction and all-cause mortality. We aimed to evaluate maternal and neonatal outcomes of pregnant women with structurally normal heart having PVC burden ≥1%. METHODS: This retrospective cohort study used data from Chang Gung Research Database. Pregnancies from January 1, 2005, through June 30, 2020, with documented maternal PVC burden ≥1% by 24-h Holter monitor were identified. Pregnant women with a diagnosis of structural heart disease or arrhythmias other than PVC were excluded. We used propensity score matching (PSM) to balance the covariates between the PVC group and normal control group. The PVC group was classified into low-PVC (<10%) and high-PVC burden subgroups. The maternal and neonatal outcomes were assessed through 6 months after delivery or termination. RESULTS: After PSM, there were 214, 61, and 46 pregnant women enrolled in the normal control group, low-PVC burden, and high-PVC burden subgroups, respectively. The high-PVC and low-PVC burden subgroups had composite adverse maternal and neonatal events similar to the control group without use of antiarrhythmic drugs (AADs), but a higher proportion of placental abruption was observed in the high-PVC burden subgroup. Maternal age, diabetes, and overweight were significant predictors of composite adverse maternal events, whereas only maternal age was a significant predictor of composite adverse neonatal events. CONCLUSIONS: High PVC burden was not associated with poor composite adverse maternal and neonatal outcomes with no need of AADs therapy in pregnant women with structurally normal heart.

Premature ventricular complexes during continuous electrocardiographic monitoring in the intensive care unit: Occurrence rates and associated patient characteristics.

AIMS AND OBJECTIVES: This study examined the occurrence rate of specific types of premature ventricular complex (PVC) alarms and whether patient demographic and/or clinical characteristics were associated with PVC occurrences. BACKGROUND: Because PVCs can signal myocardial irritability, in-hospital electrocardiographic (ECG) monitors are typically configured to alert nurses when they occur. However, PVC alarms are common and can contribute to alarm fatigue. A better understanding of occurrences of PVCs could help guide alarm management strategies. DESIGN: A secondary quantitative analysis from an alarm study. METHODS: The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist was followed. Seven PVC alarm types (vendor-specific) were described, and included isolated, couplet, bigeminy, trigeminy, run PVC (i.e. VT >2), R-on-T and PVCs/min. Negative binomial and hurdle regression analyses were computed to examine the association of patient demographic and clinical characteristics with each PVC type. RESULTS: A total of 797,072 PVC alarms (45,271 monitoring hours) occurred in 446 patients, including six who had disproportionately high PVC alarm counts (40% of the total alarms). Isolated PVCs were the most frequent type (81.13%) while R-on-T were the least common (0.29%). Significant predictors associated with higher alarms rates: older age (isolated PVCs, bigeminy and couplets); male sex and presence of PVCs on the 12-lead ECG (isolated PVCs). Hyperkalaemia at ICU admission was associated with a lower R-on-T type PVCs. CONCLUSIONS: Only a few distinct demographic and clinical characteristics were associated with the occurrence rate of PVC alarms. Further research is warranted to examine whether PVCs were associated with adverse outcomes, which could guide alarm management strategies to reduce unnecessary PVC alarms. RELEVANCE TO CLINICAL PRACTICE: Targeted alarm strategies, such as turning off certain PVC-type alarms and evaluating alarm trends in the first 24 h of admission in select patients, might add to the current practice of alarm management.

Bicuspid Aortic Valve and Premature Ventricular Beats in Athletes.

BACKGROUND: The aim of this study was to identify a possible link between bicuspid aortic valve (BAV) and premature ventricular beats (PVBs), particularly from left and right ventricular outflow tracts, and to investigate possible associations between these arrhythmias and echocardiographic abnormalities. METHODS: A comparison of sportspeople with and without BAV was performed to identify PVBs' occurrence in these two series. Then, subdividing the BAV group on the presence of cardiovascular complications due to BAV, we compared arrhythmic features between these two subgroups and echocardiographic findings between athletes with and without left and right outflow tract PVBs. RESULTS: PVBs in 343 athletes with BAV were compared with 309 athletes without BAV, showing an increased frequency (29% vs. 11.8%, p < 0.001; OR 3.1; CI 2.1-4.7) and origin from the left (18.4% vs. 3.2%, p < 0.001, OR 6.7; CI 3.4-13.4) and right (15.2% vs. 3.6%, p < 0.001, OR 4.8; CI 2.5-9.5) outflow tracts compared to other ventricular areas (fascicular PVBs p = 0.81, other morphologies p = 0.58). No difference in PVBs' occurrence was found between near normal valve BAV and pathological BAV, nor was a difference in echocardiographic characteristics found between patients with and without outflow tract arrhythmias. CONCLUSIONS: A possible causal link between BAV and PVBs was highlighted, but no association between PVBs and complicated BAV was emphasized.

Acute Impact of Fine Particulate Air Pollution on Cardiac Arrhythmias in a Population-Based Sample of Adolescents: The Penn State Child Cohort.

Background Fine particulate (fine particles with aerodynamic diameters ≤2.5 µm [PM2.5]) exposure has been associated with a risk of cardiac arrhythmias in adults. However, the association between PM2.5 exposure and cardiac arrhythmias in adolescents remains unclear. Methods and Results To investigate the association and time course between PM2.5 exposure with cardiac arrhythmias in adolescents, we analyzed the data collected from 322 adolescents who participated in the PSCC (Penn State Child Cohort) follow-up examination. We obtained individual-level 24-hour PM2.5 concentrations with a nephelometer. Concurrent with the PM2.5 measure, we obtained 24-hour ECG data using a Holter monitor, from which cardiac arrhythmias, including premature atrial contractions and premature ventricular contractions (PVCs), were identified. PM2.5 concentration and numbers of premature atrial contractions/PVCs were summarized into 30-minute-based segments. Polynomial distributed lag models within a framework of a negative binomial model were used to assess the effect of PM2.5 concentration on numbers of premature atrial contractions and PVCs. PM2.5 exposure was associated with an acute increase in number of PVCs. Specifically, a 10 µg/m3 increase in PM2.5 concentration was associated with a 2% (95% CI, 0.4%-3.3%) increase in PVC counts 0.5 to 1.0, 1.0 to 1.5, and 1.5 to 2.0 hours after the exposure. Cumulatively, a 10 µg/m3 increment in PM2.5 was associated with a 5% (95% CI, 1%-10%) increase in PVC counts within 2 hours after exposure. PM2.5 concentration was not associated with premature atrial contraction. Conclusions PM2.5 exposure was associated with an acute increased number of ventricular arrhythmias in a population-based sample of adolescents. The time course of the effect of PM2.5 on ventricular arrhythmia is within 2 hours after exposure.

Prevalence and heart rate variability characteristics of premature ventricular contractions detected by 24-hour Holter among outpatients with palpitations in China: a cross-sectional study.

OBJECTIVE: To analyse the prevalence and heart rate variability (HRV) characteristics of premature ventricular contraction (PVC) detected by 24-hour Holter among Chinese outpatients with palpitations. DESIGN: A cross-sectional study. SETTING: This study was conducted in a tertiary hospital. PARTICIPANTS: A total of 4754 outpatients who received 24-hour Holter for palpitations. MAIN OUTCOME MEASURES: Prevalence, HRV time-domain and frequency-domain analyses of 24-hour Holter, and echocardiographic parameters were assessed. Propensity score matching (PSM) was applied to balance baseline variables (age, gender) to decrease the bias between comparison groups. RESULTS: The prevalence of PVC was 67.7% (3220/4754), and was higher in men than women (69.9% vs 66.0%, p=0.004); the prevalence of frequent PVCs (PVC burden≥5%) was 7.7% (368/4754). Older patients had the highest frequency of PVC among all patients. However, among 3220 patients with PVC, younger patients' PVC burden was much higher. Matched 1:1 by age and gender, the HRV time-domain parameters in patients with PVC were all lower than those in patients without PVC (all p<0.05); for the HRV frequency-domain parameters, the patients with frequent PVCs had a higher low frequency/high frequency (LF/HF) ratio (5.4 vs 2.8, p<0.001) than those with PVC burden less than 5%. CONCLUSIONS: The prevalence of PVC and frequent PVCs were 67.7% and 7.7%, respectively, detected by 24-hour Holter among Chinese outpatients with palpitations. Decreased HRV time-domain parameters suggested the occurrence of PVC, and increased LF/HF ratio represented the imbalance of autonomic nervous system in patients with frequent PVCs. Further studies are needed to understand the HRV indexes in PVC patients.

Self-reported marijuana use and cardiac arrhythmias (from the Multiethnic Study of Atherosclerosis).

Marijuana use among all age groups has been increasing, including among older adults aged ≥65 years. There is a lack of epidemiologic data examining arrhythmia risk among users of marijuana. We evaluated cross-sectional associations between current and past marijuana smoking and arrhythmias among 1485 participants from the Multiethnic Study of Atherosclerosis who underwent extended ambulatory electrocardiographic monitoring with the Zio Patch XT. Outcomes included premature atrial contractions, runs of supraventricular tachycardia, premature ventricular contractions, and runs of nonsustained ventricular tachycardia (NSVT). Compared with never users, participants reporting current use of marijuana (n = 40, 3%) had more supraventricular tachycardia/day (adjusted geometric mean ratio [GMR] 1.42, 95% confidence interval [CI] 0.87 to 2.32), more premature atrial contractions/hour (GMR 1.22, 95% CI 0.72, 2.13), and more NSVT/day (GMR 1.28, 95% CI 0.95 to 1.73); although, CIs overlapped 1. Additionally, more frequent marijuana use was associated with more runs of NSVT/day (GMR 1.56, 95% CI 1.13, 2.17). In conclusion, our results suggest that current marijuana use may be associated with a greater burden of arrhythmias. There is a need for additional research, mainly using a prospective design, to clarify if marijuana use causes atrial and ventricular arrhythmias or other cardiovascular complications among older adults.

Clinical Characteristics of Patients with Arrhythmias of the Idiopathic Outflow Tract Ventricular: Age, Gender, Comorbidities, Laboratory Test Results, and Echocardiographic Parameters.

Context: Idiopathic ventricular arrhythmias (IVAs) are a spectrum of ventricular arrhythmia (VA) without structural heart disease (SHD), that includes premature ventricular contractions (PVCs) and ventricular tachycardia (VT). The clinical characteristics of patients with PVCs or VT remain unclear, including distribution of the origin of arrhythmias, age and gender differences, comorbidities, laboratory tests, and electrocardiographic parameters. Objective: The study intended to compare the clinical characteristics of the right ventricular outflow tract (RVOT)- and left ventricular outflow tract (LVOT)-VT of a large group of consecutive patients, to investigate the distribution of the origin of the arrhythmias, age and gender differences, comorbidities, laboratory-examination results, and echocardiographic parameters. Methods: The research team designed a retrospective study to collect data on the above-mentioned variables. Setting: The study occurred at the Second Hospital of Hebei Medical University in Shijiazhuang, China. Participants: Participants were 774 patients with symptomatic ventricular arrhythmias, 328 males and 446 females with the mean age of 48.6 ± 15.7 years, who underwent catheter ablation between January 2015 and January 2019. Participants were divided into the right ventricular outflow tract (RVOT) group and left ventricular outflow tract (LVOT) group, according to the different origins of their arrhythmias, with 428 participants in the RVOT group and 180 in the LVOT group. Outcome Measures: The research team collected and analyzed the data for the original sites of the IVAs; ages; genders; comorbidities; laboratory examinations, including routine blood tests, liver function, kidney function, blood lipid and potassium; and echocardiographic parameters. Results: Among the 774 participants, 76 had experienced VTs and 698 PVCs. The original site of IVAs was 2.38 times more likely to be in the RVOT than the LVOT, with the ratio for RVOT/LVOT = 2.38. IVAs usually occurred in participants between 50 and 70 years old and exhibited a decreasing incidence after 70 years of age. IVAs derived from the His bundle were more common in older participants, with a mean age of 60.4 ± 10.4 years, while IVAs derived from the fascicular were more common in younger patients, with a mean age of 36.08 ± 16.01 years. Compared with the LVOT group, the RVOT group was younger, 51.91 ± 14.65 years vs 46.95 ± 14.95 years, respectively (P < .001). PVCs in the RVOT group were more common in women, with the ratio of females/males = 2.10, and no gender difference existed in the overall incidence of IVAs in the LVOT group (P > .05). The most common cardiovascular comorbidities of outflow tract ventricular arrhythmias (OTVAs) were hypertension, coronary heart disease, and hyperlipidemia, while the most common noncardiovascular comorbidities were diabetes, ischemic stroke, and thyroid disease. The red-blood-cell counts, hemoglobin, creatinine, and gamma-glutamyl transpeptidase (GGT) of the LVOT group were higher than those from the RVOT, with P = .008, P = .009, P = .001, and P < .001, respectively. The left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVS), and left ventricular posterior wall thickness (LVPWT) in the LVOT group were larger than those in the RVOT group (P <.001), while the LVOT group's left ventricular ejection fraction (LVEF%) was lower than that of the RVOT group. Conclusions: The outflow tract served as the major original site of IVAs, and significant differences existed between participants in the LVOT and RVOT groups in age; gender; comorbidities; results of laboratory examinations, including red-blood-cell counts, hemoglobin, creatinine, and GGT; and echocardiographic parameters, including LVEF%, LAD, LVEDD, IVS, and LVPWT.

Ventricular Premature Complexes and Their Associated Factors in a General Population of Japanese Men.

Increased ventricular premature complexes (VPCs) are associated with a higher risk of cardiac morbidities. However, little information is available on the risk factors of Western general populations. Therefore, we aimed to assess the frequency and associated factors of VPCs in healthy general Japanese men. We conducted a population-based cross-sectional study in 517 men, aged 40 to 79 years, using 24-hour Holter electrocardiography. Age, body mass index, height, low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein cholesterol, resting heart rate, diabetes mellitus, hypertension, physical activity, smoking, alcohol consumption, lipid-lowering therapy were included in multivariable negative binomial regression to assess independent correlates for the number of VPCs per hour. We observed at least 1 VPC in 1 hour in 429 men (83%). In multivariable negative binomial regression adjusted for all covariates simultaneously, age (risk ratio [95% confidence interval] 1.91 [1.56 to 2.33] per 1-SD increment), height (1.17 [1.04 to 1.49] per 1-SD increment), resting heart rate(1.34 [1.02 to 1.77] per 1-SD increment), diabetes mellitus (2.36 [1.17 to 4.76] ), hypertension (1.90 [1.03 to 3.50]), physical activity (0.67 [0.47 to 0.97] ), current smoking (4.23 [1.86 to 9.60] ), past smoking (2.08 [1.03 to 4.19] ), current light alcohol consumption (0.16 [0.04 to 0.64] ), and lipid-lowering therapy (0.47 [0.23 to 0.96] ) were independently associated with VPCs frequency. In conclusion, VPCs frequency was independently associated with age, height, resting heart rate, diabetes mellitus, hypertension, physical activity, smoking, alcohol consumption, and lipid-lowering therapy.

Premature ventricular complexes and development of heart failure in a community-based population.

OBJECTIVE: A higher premature ventricular complex (PVC) frequency is associated with incident congestive heart failure (CHF) and death. While certain PVC characteristics may contribute to that risk, the current literature stems from patients in medical settings and is therefore prone to referral bias. This study aims to identify PVC characteristics associated with incident CHF in a community-based setting. METHODS: The Cardiovascular Health Study is a cohort of community-dwelling individuals who underwent prospective evaluation and follow-up. We analysed 24-hour Holter data to assess PVC characteristics and used multivariable logistic and Cox proportional hazards models to identify predictors of a left ventricular ejection fraction (LVEF) decline and incident CHF, respectively. RESULTS: Of 871 analysed participants, 316 participants exhibited at least 10 PVCs during the 24-hour recording. For participants with PVCs, the average age was 72±5 years, 41% were women and 93% were white. Over a median follow-up of 11 years, 34% developed CHF. After adjusting for demographics, cardiovascular comorbidities, antiarrhythmic drug use and PVC frequency, a greater heterogeneity of the PVC coupling interval was associated with an increased risk of LVEF decline and incident CHF. Of note, neither PVC duration nor coupling interval duration exhibited a statistically significant relationship with either outcome. CONCLUSIONS: In this first community-based study to identify Holter-based features of PVCs that are associated with LVEF reduction and incident CHF, the fact that coupling interval heterogeneity was an independent risk factor suggests that the mechanism of PVC generation may influence the risk of heart failure.

Electrocardiography clues in assessment of patients with premature ventricular contractions

Background/aim: Some electrocardiography (ECG) parameters such as Tp-e interval, Tp-e / QT ratio, fragmented QRS (fQRS), and heart rate variability (HRV) are related to cardiovascular mortality and morbidity. We aim to investigate the relation between premature ventricular contraction burden and these parameters on 24-h ECG recording. Materials and methods: The study is a retrospective investigation of the 24-h Holter ECG and echocardiography of 199 patients who underwent the procedures due to complaints of palpitation. A frequency of < 10% PVCs / 24 h was classified as seldom group (98 patients), while > 10% PVCs / 24 h was designated as frequent group (101 patients). Results: Tp-e interval was significantly longer (62 [54­78] vs 75 [60­84], p < 0.001), Tp-e / QT ratio was significantly increased (0.18 [0.16­0.20] vs 0.21 [0.18­0.22], p = 0.001) in frequent PVC group. The percentage of fQRS was significantly increased in frequent PVC group (30.6% vs 47.5%, p = 0.015). When the groups were compared, no significant difference was found in HRV time domain indices. Positive correlations were observed between PVC burden and Tp-e (r = 0.304, p < 0.001), Tp-e / QT (r = 0.275, p < 0.001). Conclusion: Our study showed that Tp-e interval, Tp-e / QT and fQRS are associated with frequency of PVCs. These measurements in patients with PVCs may form part of assessment of cardiovascular risk.

Effect of age and sex on the incidence of ventricular arrhythmia in a rat model of acute ischemia.

BACKGROUND: The impact of sex and age on the arrhythmic susceptibility within the setting of acute ischemia is masked by the fact that acute coronary events result from coronary artery disease appearing with age much earlier among men than among women. METHODS AND RESULTS: LAD ligation or sham operations were performed in rats of both sexes at the age 3 and 24 months. An ECG was recorded continuously for 6 h after the operation. The number of early and late premature ventricular beats (PVBs), episodes of ventricular tachycardia (VT) and fibrillation (VF), heart rate, QRS, QT and Tpeak-Tend duration were analysed. Epicardial action potentials were recorded in vivo, Ca2+ signaling was evaluated in isolated cardiomyocytes, fibrosis and connexin-43 expression and localization were measured in the septum. PVBs, VT and VF episodes are much more common in older males than in young males and females independently from their age. Fibrosis with varying intensity in different muscle layers, hypertrophy of cardiomyocytes, reduced number of gap junctions and their appearance on the lateral myocyte membrane, QT prolongation, increase transmural dispersion of repolarisation and a decreased function of SERCA2a may increase the propensity to arrhythmia within the setting of acute ischemia. CONCLUSION: We show that the male sex, especially in case of older individuals is a strong predictor of increased arrhythmic susceptibility within the acute ischemia setting regardless of its impact on the occurrence of cardiovascular diseases. A personalized sex-dependent prevention treatment is needed to reduce the mortality in acute phases of myocardial infarction.

Sex differences in the origin of Purkinje ectopy-initiated idiopathic ventricular fibrillation.

BACKGROUND: Purkinje ectopics (PurkEs) are major triggers of idiopathic ventricular fibrillation (VF). Identifying clinical factors associated with specific PurkE characteristics could yield insights into the mechanisms of Purkinje-mediated arrhythmogenicity. OBJECTIVE: The purpose of this study was to examine the associations of clinical, environmental, and genetic factors with PurkE origin in patients with PurkE-initiated idiopathic VF. METHODS: Consecutive patients with PurkE-initiated idiopathic VF from 4 arrhythmia referral centers were included. We evaluated demographic characteristics, medical history, clinical circumstances associated with index VF events, and electrophysiological characteristics of PurkEs. An electrophysiology study was performed in most patients to confirm the Purkinje origin. RESULTS: Eighty-three patients were included (mean age 38 ± 14 years; 44 [53%] women), of whom 32 had a history of syncope. Forty-four patients had VF at rest. PurkEs originated from the right ventricle (RV) in 41 patients (49%), from the left ventricle (LV) in 36 (44%), and from both ventricles in 6 (7%). Seasonal and circadian distributions of VF episodes were similar according to PurkE origin. The clinical characteristics of patients with RV vs LV PurkE origins were similar, except for sex. RV PurkEs were more frequent in men than in women (76% vs 24%), whereas LV and biventricular PurkEs were more frequent in women (81% vs 19% and 83% vs 17%, respectively) (P < .0001). CONCLUSION: PurkEs triggering idiopathic VF originate dominantly from the RV in men and from the LV or both ventricles in women, adding to other sex-related arrhythmias such as Brugada syndrome or long QT syndrome. Sex-based factors influencing Purkinje arrhythmogenicity warrant investigation.

Association between exposure to Efavirenz and substrates of dysrhythmia in HIV-infected young adults.

BACKGROUND: Dysrhythmia and sudden cardiac arrest occur more likely in HIV patients than healthy subjects. Thus, we need to examine dysrhythmias adverse effects of medications including Efavirenz as early as possible especially in young subjects. HYPOTHESIS: Efavirenz might have contributed to increased risk of developing common types of dysrhythmia in young HIV infected patients. METHODS: We performed a retrospective cohort study among 62 patients on Efavirenz and 38 controls. All participants were under 40 years old without cardiovascular disease. Total significant dysrhythmia in 24-hour ECG monitoring was the primary endpoint determined as the composite of high premature ventricular contraction (PVC) (>500 beats per 24 hours), high premature atrial contraction (PAC) (>500 bp24h), sinus pause, atrioventricular blocks, ventricular tachycardia, prolonged QTc, and low heart rate variability (HRV). Modified composite dysrhythmia consisted of low HRV (SD of normal-to-normal [SDNN]), high PVC and prolonged QT. RESULTS: Mean heart rate, Efavirenz regimen, male gender, and CD4 count predicted total dysrhythmia. Odds ratios were 1.108, 2.90, 4.36, and 0.96, respectively. The incidence of total dysrhythmia, high PVC, high PAC, low HRV(SDNN), and prolonged QTc were 54.8%, 41.85%, 9.71%, 45.2%, and 12.9% in patients on Efavirenz against 42.11%, 31.64%, 0%, 34.2%, and 7.91% in controls, respectively (p-values: .031, .001, <.0001, .063, and .043 respectively). Modified composite dysrhythmia was also more frequent in Efavirenz group than that of control group (69.42% vs. 52.60%, respectively p = .032). CONCLUSIONS: We found that patients with Efavirenz had higher prevalence of frequent PVC, frequent PAC, total significant dysrhythmia, Low HRV and prolonged QTc than controls.