Determining the optimal duration for premature ventricular contraction monitoring.

BACKGROUND: Premature ventricular contractions (VPC) have hour-to-hour and day-to-day variation. High VPC burden correlates with cardiomyopathy. OBJECTIVE: To determine the optimal duration for ambulatory electrocardiogram monitoring for accurate assessment of VPC burden. METHODS: Our group performed a retrospective analysis on patch monitors used for any indication with overall VPC burden ≥5.0% between February 1, 2016, and February 1, 2020. We generated cumulative daily VPC averages for each day of wear and performed linear regression analysis between each cumulative daily average and overall burden. Patients were divided into groups based on low or high VPC frequency, and the analysis was repeated. Split-sample validation was used to internally validate the overall prediction model. RESULTS: A total of 116 patches representing 107 patients (mean age: 64.5; female: 48%) were analyzed. Mean overall VPC burden was 13.4% ± 7.5% (range: 5.0%-42.0%). Day 1 R2 was 60%, P < .001, and continued to increase to R2 88%, P < .001 at day 14. Median percent and absolute error decreased from 22.70% (interquartile range [IQR]: 9.73-34.39) and 2.58% (IQR: 1.24-4.59) at day 1 to 5.62% (IQR: 2.82-8.39) and 0.55% (IQR: 0.28-1.05) at day 14. Patients with higher overall VPC frequencies achieved a more rapid rise in R2 relative to those with lower frequencies. Split-sample validation supported the internal validity of our linear regression prediction model. CONCLUSION: Mobile telemetry for a period of ∼7 days accurately reflects overall VPC burden. Measurement of VPC burden for only 24-48 hours may not accurately reflect total burden. Monitoring for 2 weeks or longer adds little additional VPC information.

Early repolarization pattern in an ethnically diverse population: Increased risk in Hispanics.

BACKGROUND: Early repolarization (ER) pattern on ECG is associated with an increased mortality in Caucasians. This study analyzed the association between ER pattern and all-cause mortality in a population of multiple ethnicities. METHODS: A total of 20 000 individuals were randomly selected and their ECGs were analyzed for ER pattern using the 2015 consensus: end-QRS notching or slurring with a J-point (Jp) ≥0.1 mV in contiguous inferior or lateral leads. Exclusion criteria were age <18, QRS duration of ≥120 ms, and acute myocardial infarction. Kaplan-Meier survival curves were used to assess crude survival, and multivariable logistic regression models were used to determine predictors of all-cause mortality. RESULTS: A total of 17 901 patients with a mean age of 53 met inclusion criteria. Individuals were 62% female, 14% White, 37% Black, 40% Hispanic, and 9% other. Median follow-up time was 6.4 years. ER pattern was noted in 995 (5.6%) patients. Jp ≥2 mm was noted in 282 (1.6%) patients. In those with ER pattern and Jp ≥1 mm, there was no difference in mortality when compared to individuals without Jp elevation (odds ratio [OR]: 0.962, 95% confidence of interval [CI]: 0.819-1.131). Patients with Jp ≥2 mm had a significantly increased all-cause mortality (OR: 1.333, 95% CI: 1.009-1.742). This increased mortality was also significant in Hispanic patients with Jp ≥2 mm (OR: 1.584, 95% CI: 1.003-2.502). CONCLUSION: ER pattern with Jp ≥2 mm is associated with increased mortality in a multiethnic population, apparently driven by an increased risk in Hispanics.

Use of antimicrobial agent pocket irrigation for cardiovascular implantable electronic device infection prophylaxis: Results from an international survey.

PURPOSE: Survey the usage and application protocol of antimicrobial agent pocket irrigation for cardiovascular implantable electronic device (CIED) infection prophylaxis. BACKGROUND: Local antibiotic usage for CIED infection prophylaxis, in particular pocket irrigation, is a well-known strategy but with little data on its clinical effectiveness. METHODS: An anonymous voluntary online survey was sent to a total of 2,092 arrhythmia-oriented cardiologists in 51 countries (1,490 from the United States). RESULTS: There were 487 responses (response rate 23.3%: U.S. 28.2%, outside of the U.S. 11.1%). Eighty-seven percent of respondents use intraoperative antimicrobial agent pocket irrigation and/or an antimicrobial eluting pouch to reduce CIED infection. Fifty-four percent of respondents believe that it is effective to use an antimicrobial agent pocket irrigation to reduce CIED infection; 33% of respondents are uncertain; a few consider this strategy ineffective (13%) or offered no opinion. Significant differences exist in the practice patterns and beliefs between the U.S. and non-U.S. countries (P < 0.05). Ninety-eight percent of respondents report using the same pocket irrigation protocol for permanent pacemaker versus implantable cardioverter defibrillator. Bacitracin (48%), vancomycin (39%), and a cephalosporin (29%) are the most commonly chosen antibiotics. A majority of the respondents are unaware of the cost of using antimicrobial agent pocket irrigation (69%) and neither are they concerned (67%). CONCLUSION: This international survey suggests that, while there are little clinical data to support or discourage such practice, the usage of antimicrobial agent pocket irrigation for CIED infection prophylaxis is widely used in current practice.

Efficacy and Safety Outcomes of Direct Oral Anticoagulants and Amiodarone in Patients with Atrial Fibrillation.

BACKGROUND: Direct oral anticoagulants (DOACs) and amiodarone are widely used in the treatment of nonvalvular atrial fibrillation. The DOACs are P-glycoprotein (P-gp) and cytochrome p-450 (CYP3A4) substrates. Direct oral anticoagulant levels may be increased by the concomitant use of potent dual P-gp/CYP3A4 inhibitors, such as amiodarone, which can potentially translate into adverse clinical outcomes. We aimed to assess the efficacy and safety of drug-drug interaction by the concomitant use of DOACs and amiodarone. METHODS: We performed a systematic review of MEDLINE, the Cochrane Central Register of Clinical Trials, and Embase, limiting our search to randomized controlled trials of patients with atrial fibrillation that have compared DOACs versus warfarin for prophylaxis of stroke or systemic embolism, to analyze the impact on stroke or systemic embolism, major bleeding, and intracranial bleeding risk in patients with concomitant use of amiodarone. Risk ratio (RR) 95% confidence intervals were measured using the Mantel-Haenszel method. The fixed effects model was used owing to heterogeneity (I2) < 25%. RESULTS: Four trials with a total of 71,683 patients were analyzed, from which 5% of patients (n = 3212) were concomitantly taking DOAC and amiodarone. We found no statistically significant difference for any of the clinical outcomes (stroke or systemic embolism [RR 0.85; 95% CI, 0.67-1.06], major bleeding [RR 0.91; 95% CI, 0.77-1.07], or intracranial bleeding [RR 1.10; 95% CI, 0.68-1.78]) among patients taking DOAC and amiodarone versus DOAC without amiodarone. CONCLUSION: On the basis of the results of this meta-analysis, co-administration of DOACs and amiodarone, a dual P-gp/CYP3A4 inhibitor, does not seem to affect efficacy or safety outcomes in patients with atrial fibrillation.

Socioeconomic status and the development of atrial fibrillation in Hispanics, African Americans and non-Hispanic whites.

BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia and is associated with significant morbidity and mortality. Despite having a higher burden of traditional AF risk factors, African American and Hispanic minorities have a lower incidence of AF when compared to non-Hispanic whites, referred to as the "racial paradox." HYPOTHESIS: Lower SES among Hispanics and African Americans may help to explain the lower incidence rates of AF compared to non-Hispanic whites. METHODS: An electrocardiogram/electronic medical records database in New York State was interrogated for individuals free of AF for development of subsequent AF from 2000 to 2013. SES was assessed per zip code via a composite of 6 measures Z-scored to the New York State average. SES was reclassified into decile groups. Cox regression analysis controlling for all baseline differences was used to estimate the independent predictive ability of SES for AF. RESULTS: We identified 48 631 persons (43% Hispanic, 37% African Americans, and 20% non-Hispanic white; mean age 59 years; mean follow-up of 3.2 years) of which 4556 AF cases occurred. Hispanics and African Americans had lower AF risk than whites in all SES deciles (P < 0.001 by log-rank test). Higher SES was borderline associated with lower AF risk (hazard ratio: 0.990, 95% confidence interval: 0.980-1.001, P = 0.061). P trend analysis was not significant by any race/ethnic group by SES deciles for AF. CONCLUSIONS: Our study suggests that non-Hispanic whites were at higher risk for AF compared to nonwhites, and this was independent of SES.

Atrial fibrillation inducibility during cavo-tricuspid isthmus dependent atrial flutter ablation for the prediction of clinical atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) and cavo-tricuspid isthmus (CTI) dependent atrial flutter (AFL) are two separate entities that coexist in a significant percentage of patients. METHODS: We sought to investigate whether AF inducibility during CTI AFL ablation predicted the occurrence of AF at follow up after AFL ablation. Univariate and multivariate analyses were performed. RESULTS: A total of 154 patients (male: 72%, age: 61±13) with AFL and without history of AF were included. All patients underwent successful CTI dependent AFL ablation demonstrated by bidirectional block. During ablation, AF was seen or induced in 28 (18%) patients. After a mean follow up of 34±24months a total of 50 patients (32%) were noted with clinically manifest AF. From the patients who had inducible AF during AFL ablation, 50% developed post-procedural AF. From those in whom AF could not be induced, only 29% were documented with AF after ablation. Univariate and multivariate analyses revealed that only age and AF inducibility during AFL ablation were predictors of AF. Univariate analysis (age p=0.038 and inducible AF p=0.032 with odds ratio of 1.030 [95% CI (1.002-1.059)] and 2.500 [95% CI (1.084-5.765)], respectively) and multivariate analyses (age p=0.011 and inducible AF p=0.016 with adjusted odds ratio of 1.043 [95% CI (1.010-1.077)] and 3.293 [95% CI (1.250-8.676)], respectively). CONCLUSION: AF inducibility in patients undergoing CTI AFL without history of AF is a strong predictor of AF occurrence in the future. Appropriate cardiology follow-up must be encouraged in this high-risk population as stroke prevention strategies can be appropriately introduced in a timely matter especially in patients with elevated CHA2DS2-VASc scores (≥2).

Socioeconomic Status as a Predictor of Mortality in Patients Admitted With Atrial Fibrillation.

Lower socioeconomic status (SES) is associated with a higher risk of cardiovascular disease. However, the association between SES and mortality in patients with atrial fibrillation (AF) is not clear. We examined whether SES predicts all-cause mortality in patients hospitalized with AF. This is a retrospective study of patients aged >18 years, admitted with a primary diagnosis of AF to Montefiore Medical Center between 2000 and 2010. Multivariable logistic regression models were used to determine predictors of survival adjusted for age, gender, heart failure, diabetes mellitus, chronic kidney disease, previous myocardial infraction, chronic obstructive pulmonary disease, hypertension, peripheral vascular disease, and SES. SES was determined using the New York City Department of Health Standardized Score (a log composite score of household income, value of housing units, net rental income, household occupations, and educational level). The cohort was divided into quartiles based on SES score, with Q4 the highest and Q1 the lowest SES score. There were 4,503 patients identified with a mean follow up of 4.5 years in the following SES quartiles: Q1 (n = 1,132), Q2 (n = 1,119), Q3 (n = 1,126), and Q4 (n = 1,126). The unadjusted mortality varied across quartiles (Q1 to Q4), 54%, 58%, 56%, and 59%, respectively (p = 0.004). After controlling for other variables in the multivariable analysis, patients with the lowest SES (Q1) had a significantly higher mortality than patients in the quartile with the highest (Q4) SES (odds ratio 1.3, CI 1.1 to 1.5). In conclusion, patients admitted to the hospital with AF have varying mortality based on their SES. After controlling for co-morbidities, patients with AF and lower SES scores had higher mortality. Further research studies are warranted to study this risk of increased mortality in AF population.

Electroanatomic mapping systems (CARTO/EnSite NavX) vs. conventional mapping for ablation procedures in a training program.

BACKGROUND: Three-dimensional electroanatomic mapping (EAM) systems reduce radiation exposure when radio frequency catheter ablation (RFCA) procedures are performed by well-trained senior operators. Given the steep learning curve associated with complex RFCA, trainees and their mentors must rely on multiple imaging modalities to maximize safety and success, which might increase procedure and fluoroscopy times. The objective of the present study is to determine if 3-D EAM (CARTO and ESI-NavX) improves procedural outcomes (fluoroscopy time, radio frequency time, procedure duration, complication, and success rates) during CA procedures as compared to fluoroscopically guided conventional mapping alone in an academic teaching hospital. METHODS: We analyzed a total of 1070 consecutive RFCA procedures over an 8-year period for fluoroscopic time stratified by ablation target and mapping system. Multivariate logistic regression and adjusted odds ratios were calculated for each variable. RESULTS: No statistically significant differences in acute success rates were noted between conventional and 3-D mapping cases [CARTO (p = 0.68) or ESI-NavX (p = 0.20)]. Moreover, complication rates were also not significantly different between CARTO (p = 0.23) and ESI-NavX (p = 0.53) when compared to conventional mapping. Procedure, radio frequency, and fluoroscopy times were significantly longer with CARTO and ESI-NavX versus conventional mapping [fluoroscopy time: CARTO, 28.3 min; ESI, 28.5 min; and conventional, 24.3 min; p < 0.001)]. CONCLUSIONS: The use of 3-D EAM systems during teaching cases significantly increases radiation exposure when compared with conventional mapping. These findings suggest a need to develop alternative training strategies that enhance confidence and safety during catheter manipulation and allow for reduced fluoroscopy and procedure times during RFCA.

Drug-induced torsades de pointes in an underserved urban population. Methadone: is there therapeutic equipoise?

BACKGROUND: Although it has been well established that methadone use can result in prolonged QTc/torsades de pointes (TdP) and has been labeled as one of the main drugs that cause TdP, it is still prescribed indiscriminately, and several cases of methadone-associated TdP have been seen in our community. METHODS: Our objective was to determine the associated factors for prolonged QTc and the development of torsades de pointes (TdP) in our underserved patient population. We found 12,550 ECGs with prolonged QTc between 2002 and 2013. Medical records were reviewed in order to identify precipitating factors for prolonged QTc and to detect incidence of TdP. RESULTS: We identified 2735 patients with prolonged QTc who met the inclusion criteria. Of these, 89 (3%) experienced TdP. There was a greater prevalence of HIV infection in the TdP group (11.2 vs. 3.7%, p < 0.001). Furosemide, hydrochlorothiazide, selective serotonin reuptake inhibitors (SSRIs), amiodarone, ciprofloxacin, methadone, haloperidol, and azithromycin were the drugs most often associated with prolonged QTc (31, 8.2, 7.6, 7.1, 3.9, 3.4 and 3.3%, respectively). However, the agents most commonly associated with TdP were furosemide (39.3%), methadone (27%), SSRIs (19.1%), amiodarone (18%), and dofetilide (9%). The medications with statistical significance in the multivariate analysis for TdP development in descending order were as follows: ranolazine (odds ratios [OR] = 53.61, 95% confidence interval [CI] 5.4-524, p < 0.001), dofetilide (OR = 25, CI 6.47-103.16, p < 0.001), voriconazole (OR = 21.40, CI 3.24-124.25, p < 0.001), verapamil (OR = 10.98, CI 2.62-44.96, p < 0.001), sotalol (OR = 12.72, 1.95-82.81, p = 0.008), methadone (OR = 9.89, CI 4.05-24.15, p < 0.001), and SSRI (OR = 2.26, CI 1.10-5.96, p < 0.001). This multivariate analysis revealed that amiodarone and HIV infection were not implicated in TdP. CONCLUSION: Methadone was by far the leading medication implicated in the development of TdP and an independent predictor in both univariate and multivariate analyses despite the fact that it was not the most common QT-prolonging medication in our population.

Validation of the Framingham Heart Study and CHARGE-AF Risk Scores for Atrial Fibrillation in Hispanics, African-Americans, and Non-Hispanic Whites.

A risk score for atrial fibrillation (AF) has been developed by the Framingham Heart Study and Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE)-AF consortium. However, validation of these risk scores in an inner-city population is uncertain. Thus, a validation model was built using the Framingham Risk Score for AF and CHARGE-AF covariates. An in and outpatient electrocardiographic database was interrogated from 2000 to 2013 for the development of AF. Patients were included if their age was >45 and <95 years, had <10-year follow-up, if their initial electrocardiogram was without AF, had ≥ 2 electrocardiograms, and declared a race and/or ethnicity as non-Hispanic white, African-American, or Hispanic. For the Framingham Heart Study, 49,599 patients met inclusion criteria, of which 4,860 developed AF. Discrimination analysis using area under the curve (AUC) for original risk equations: non-Hispanic white AUC = 0.712 (95% confidence interval [CI] 0.694 to 0.731), African-American AUC = 0.733 (95% CI 0.716 to 0.751), and Hispanic AUC = 0.740 (95% CI 0.723 to 0.757). For the CHARGE-AF, 45,571 patients met inclusion criteria, of which 4,512 developed AF. Non-Hispanic white AUC = 0.673 (95% CI 0.652 to 0.694), African-American AUC = 0.706 (95% CI 0.685 to 0.727), and Hispanic AUC = 0.711 (95% CI 0.691 to 0.732). Calibration analysis showed qualitative similarities between cohorts. In conclusion, this is the first study to validate both the Framingham Heart Study and CHARGE-AF risk scores in both a Hispanic and African-American cohort. All models predicted AF well across all race and ethnic cohorts.

Referral Patterns for Primary Prophylaxis Implantable Cardioverter Defibrillator Therapy for an Urban US Population.

Implantable cardioverter defibrillators (ICDs) have been demonstrated to improve survival for both primary and secondary prevention of sudden cardiac arrest. However, studies suggest that ICD therapy is underused in appropriate candidates. Sex and racial disparities in ICD use have been suggested. We sought to characterize the referral patterns of high-risk patients for the primary prophylaxis of sudden cardiac arrest at a tertiary academic medical center serving a diverse population in an urban US setting. Electronic hospital databases were retrospective reviewed for patients meeting criteria for prophylactic ICD implantation. We evaluated the association of gender, age, race, and primary language with the referral and subsequent implantation of an ICD. We identified 1,055 patients satisfying prophylactic ICD criteria: 600 men, mean age 62.6 years, 27.6% black, 19.3% white, 23.3% Hispanic, and 49.8% primary language of English. Of the 673 patients (63.7%) referred for ICD evaluation, 345 underwent implantation, 125 declined, and 203 had significant co-morbidities that precluded implantation. Gender, race, and primary language were not associated with referral for ICD or with decision to proceed with implantation. Patients of increased age were less likely to be referred for ICD and were more likely to refuse implantation. ICD therapy was not considered in 146 patients eligible for prophylactic implantation. In conclusion, referral rates for ICD consideration were higher at our institution than in previous reports. Nonetheless, 14% of appropriate patients were not considered. This argues for the importance of increased education for patients and referring physicians.

The Prognostic Value of Early Repolarization with ST-Segment Elevation by Age and Gender in the Hispanic Population.

BACKGROUND: Early repolarization (ER), once thought to be a benign finding on electrocardiograph (ECG), has recently been associated with an increased risk of sudden cardiac death. As there are limited data in the Hispanic population, we investigated possible associations between automated ECG ER readings and overall mortality, using the classic definition involving J-point elevation with ST segment elevation. METHODS: An ECG and electronic medical record (EMR) database from a regional medical center was interrogated. Inclusion criteria included Hispanic ethnicity and age over 18 from 2000 to 2011. A Cox model assessed the outcome of death. Varying morphological characteristics of ER were analyzed for high-risk features. RESULTS: There were n = 33,944 Hispanics of who n = 532 (1.6%) had ER with a mean follow-up period of 5.29 years. After adjustment for demographic, clinical, lifestyle, and laboratory variables, ER was not significantly related to all-cause mortality (hazard ratio [HR]: 1.18, 95% confidence interval [CI]: 0.90-1.54, P = 0.23). However, mortality risk of ER varied by gender and age (P interaction = 0.007). The risk of ER for mortality was highest for females (HR: 2.01, CI: 1.39-3.10, P = 0.001), with the highest overall risk for women over the age of 75 (HR: 2.09, CI: 1.12-3.92, P = 0.021) compared to women under age 75 (HR: 1.72, CI: 0.95-3.11, P = 0.075). CONCLUSIONS: ER is not associated with an increased risk of death in the overall Hispanic population. However, our analysis suggests a higher risk of overall mortality in the elderly Hispanic female population with ER.

Left Atrial Appendage Occlusion Device and Novel Oral Anticoagulants Versus Warfarin for Stroke Prevention in Nonvalvular Atrial Fibrillation: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Nonvalvular atrial fibrillation is the most common arrhythmia. Patients with nonvalvular atrial fibrillation are at increased risk of stroke; therefore, we evaluated the efficacy and safety of different approaches to prevent this major complication. METHODS AND RESULTS: We conducted electronic database searches of phase III randomized controlled trials. The groups were novel oral anticoagulants, Watchman left atrial appendage occlusion device (DEVICE), and warfarin. Efficacy outcomes were stroke or systemic embolism, and all-cause mortality. Safety outcome was major bleeding and procedure-related complications. A subgroup analysis of the elderly population was done. We used random-effects model to compare pooled outcomes and tested for heterogeneity. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed for each outcome. Seven randomized controlled trials (n=73,978) were included. There was a significant difference favoring novel oral anticoagulants for systemic embolism (OR, 0.84; 95% CI, 0.72-0.97; P=0.01), all-cause mortality (OR, 0.89; 95% CI, 0.84-0.94; P<0.001), and safety outcomes (OR, 0.79; 95% CI, 0.65-0.97; P=0.026) compared with warfarin. No difference was seen between DEVICE and warfarin for efficacy end points; however, DEVICE had more complications (OR, 1.85; 95% CI, 1.14-3.01; P=0.012). In the elderly (6 randomized controlled trials, n=30,699), systemic embolism was favored with novel oral anticoagulants over warfarin (OR, 0.77; 95% CI, 0.68-0.87; P≤0.001). No evidence of significant publication bias was found. CONCLUSIONS: Novel oral anticoagulants is superior to warfarin for stroke prevention in nonvalvular atrial fibrillation. This benefit was also observed in the elderly population. DEVICE is a reasonable noninferior alternative to warfarin for stroke prevention, but cautious use is essential given safety concerns.

Validation of PR interval length as a criterion for development of atrial fibrillation in non-Hispanic whites, African Americans and Hispanics.

BACKGROUND: PR interval prolongation on electrocardiogram (ECG) increases the risk of atrial fibrillation (AF). Non-Hispanic Whites are at higher risk of AF compared to African Americans and Hispanics. However, it remains unknown if prolongation of the PR interval for the development of AF varies by race/ethnicity. Therefore, we determined whether race affects the PR interval length's ability to predict AF and if the commonly used criterion of 200 ms in AF prediction models can continue to be used for non-White cohorts. METHODS: This is a retrospective epidemiological study of consecutive inpatient and outpatients. An ECG database was initially interrogated. Patients were included if their initial ECG demonstrated sinus rhythm and had two or more electrocardiograms and declared a race and/or ethnicity as non-Hispanic White, African American or Hispanic. Development of AF was stratified by race/ethnicity along varying PR intervals. Cox models controlled for age, gender, race/ethnicity, systolic blood pressure, BMI, QRS, QTc, heart rate, murmur, treatment for hypertension, heart failure and use of AV nodal blocking agents to assess PR interval's predictive ability for development of AF. RESULTS: 50,870 patients met inclusion criteria of which 5,199 developed AF over 3.72 mean years of follow-up. When the PR interval was separated by quantile, prolongation of the PR interval to predict AF first became significant in Hispanic and African Americans at the 92.5th quantile of 196-201 ms (HR: 1.42, 95% CI: 1.09-1.86, p=0.01; HR: 1.32, 95% CI: 1.07-1.64, p=0.01, respectively) then in non-Hispanic Whites at the 95th quantile at 203-212 ms (HR: 1.24, 95% CI: 1.24-1.53, p=0.04). For those with a PR interval above 200 ms, African Americans had a lower risk than non-Hispanic Whites to develop AF (HR: 0.80, 95% CI: 0.64-0.95, p=0.012), however, no significant difference was demonstrated in Hispanics. CONCLUSIONS: This is the first study to validate a PR interval value of 200 ms as a criterion in African Americans and Hispanics for the development of AF. However, a value of 200 ms may be less sensitive as a predictive measure for the development of AF in African Americans compared to non-Hispanic Whites.