Rates of pulmonary vein reconnection at repeat ablation for recurrent atrial fibrillation and its impact on outcomes among females and males.

BACKGROUND: Several studies have demonstrated that females have a higher risk of arrhythmia recurrence after pulmonary vein (PV) isolation for atrial fibrillation (AF). There are limited data on sex-based differences in PV reconnection rates at repeat ablation. We aimed to investigate sex-based differences in electrophysiological findings and atrial arrhythmia recurrence after repeat AF ablation METHODS: We conducted a retrospective study of 161 consecutive patients (32% female, age 65 ± 10 years) who underwent repeat AF ablation after index PV isolation between 2010 and 2022. Demographics, procedural characteristics and follow-up data were collected. Recurrent atrial tachycardia (AT)/AF was defined as any atrial arrhythmia ≥30 s in duration. RESULTS: Compared to males, females tended to be older and had a significantly higher prevalence of prior valve surgery (10 vs. 2%; P = .03). At repeat ablation, PV reconnection was found in 119 (74%) patients. Males were more likely to have PV reconnection at repeat ablation compared to females (81 vs. 59%; P = .004). Excluding repeat PV isolation, there were no significant differences in adjunctive ablation strategies performed at repeat ablation between females and males. During follow-up, there were no significant differences in freedom from AT/AF recurrence between females and males after repeat ablation (63 vs. 59% at 2 years, respectively; P = .48). CONCLUSIONS: After initial PV isolation, significantly fewer females have evidence of PV reconnection at the time of repeat ablation for recurrent AF. Despite this difference, long-term freedom from AT/AF was similar between females and males after repeat ablation.

Localized Re-Entry Is a Frequent Mechanism of De Novo Atypical Flutter.

BACKGROUND: Limited data exist about the origins and mechanisms of atypical atrial flutter that occurs in the absence of prior ablation or surgery. OBJECTIVES: The aims of this study were to report a large cohort of patients who presented for catheter ablation of de novo atypical flutters, to identify the most common locations and mechanisms of arrhythmia, and to describe outcomes after ablation. METHODS: Demographic, electrophysiological, and outcome data were collected for patients who underwent ablation of de novo atypical flutter. RESULTS: The mechanisms of 85 atypical flutters were identified in 62 patients and localized to the left atrium (LA) in 58 and right atrium (RA) in 27. In the LA, mechanisms were classified as macro-re-entry in 29 (50%) and localized re-entry in 29 (50%), whereas in the RA, mechanisms were macro-re-entry in 8 (30%) and localized re-entry in 19 (70%) (proportion of localized re-entry in the LA vs. RA, P = 0.08). Nine patients had both localized and macro-re-entrant atypical flutters. In the LA, localized re-entry was commonly found in the anterior LA, followed by the pulmonary veins and septum. In the RA, localized re-entry was found at various sites, including the lateral or posterior RA, septum, and coronary sinus ostium. During 39.4 months (Q1-Q3: 18.2-65.8 months) of follow-up, atrial arrhythmias occurred in 66% of patients after a single ablation and in 50% after >1 ablation. Among patients who underwent repeat ablation, compared with the index arrhythmia, different tachycardia circuits or arrhythmias were documented in 13 of 18 cases (72%). CONCLUSIONS: Atypical atrial flutters in patients without prior surgery or complex ablation are often due to localized re-entry (approximately 50% in the LA and a higher frequency in the RA). Other atrial tachycardias commonly occur during long-term follow-up following ablation, suggesting progressive atrial myopathy in these patients.

Why presumptions are important in occupational health: The example of COVID-19 infection as an occupational disease.

Workers who become ill or injured on the job while undertaking extraordinary risks on behalf of the public are, at times, granted facilitated access to workers' compensation (WC) benefits through the application of presumptions in the compensation process. Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, a broad range of occupational groups faced an elevated risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure at work to perform vital services to maintain our food supply, sustain needed transportation, provide health care, assure energy supply and others. Some states or jurisdictions in the United States recognized both the risk and the service of these workers by enacting COVID-19 presumption laws to streamline selected essential workers' eligibility for WC benefits. Other states did not. Results of these contrasting public approaches permit an examination of the impact of presumptions in compensation by examining the frequency and outcomes of COVID-19 claims in "COVID-19 presumption" and "nonpresumption" states. Despite state-level variations in economic response to the pandemic, industry mix, and presumption eligibility criteria, the use of COVID-19 presumptions appears to have substantially increased claim filing rates and improved access to benefits. Lastly, the additional costs of COVID-19 claims to employers and insurers were lower than initially predicted. In response to future airborne infectious disease outbreaks, workers' compensation presumption laws should be universally implemented to permit a broad range of high-risk workers to work on the public's behalf without fear of losing wages and incurring medical expenses associated with a work-related viral exposure.

Ventricular Tachycardia Due to Triggered Activity: Role of Early and Delayed Afterdepolarizations.

Most forms of sustained ventricular tachycardia (VT) are caused by re-entry, resulting from altered myocardial conduction and refractoriness secondary to underlying structural heart disease. In contrast, VT caused by triggered activity (TA) is unrelated to an abnormal structural substrate and is often caused by molecular defects affecting ion channel function or regulation of intracellular calcium cycling. This review summarizes the cellular and molecular bases underlying TA and exemplifies their clinical relevance with selective representative scenarios. The underlying basis of TA caused by delayed afterdepolarizations is related to sarcoplasmic reticulum calcium overload, calcium waves, and diastolic sarcoplasmic reticulum calcium leak. Clinical examples of TA caused by delayed afterdepolarizations include sustained right and left ventricular outflow tract tachycardia and catecholaminergic polymorphic VT. The other form of afterpotentials, early afterdepolarizations, are systolic events and inscribe early afterdepolarizations during phase 2 or phase 3 of the action potential. The fundamental defect is a decrease in repolarization reserve with associated increases in late plateau inward currents. Malignant ventricular arrhythmias in the long QT syndromes are initiated by early afterdepolarization-mediated TA. An understanding of the molecular and cellular bases of these arrhythmias has resulted in generally effective pharmacologic-based therapies, but these are nonspecific agents that have off-target effects. Therapeutic efficacy may need to be augmented with an implantable defibrillator. Next-generation therapies will include novel agents that rescue arrhythmogenic abnormalities in cellular signaling pathways and gene therapy approaches that transfer or edit pathogenic gene variants or silence mutant messenger ribonucleic acid.

A 20-year Follow-up of the International Early Lung Cancer Action Program (I-ELCAP).

Background The low-dose CT (≤3 mGy) screening report of 1000 Early Lung Cancer Action Program (ELCAP) participants in 1999 led to the International ELCAP (I-ELCAP) collaboration, which enrolled 31 567 participants in annual low-dose CT screening between 1992 and 2005. In 2006, I-ELCAP investigators reported the 10-year lung cancer-specific survival of 80% for 484 participants diagnosed with a first primary lung cancer through annual screening, with a high frequency of clinical stage I lung cancer (85%). Purpose To update the cure rate by determining the 20-year lung cancer-specific survival of participants diagnosed with first primary lung cancer through annual low-dose CT screening in the expanded I-ELCAP cohort. Materials and Methods For participants enrolled in the HIPAA-compliant prospective I-ELCAP cohort between 1992 and 2022 and observed until December 30, 2022, Kaplan-Meier survival analysis was used to determine the 10- and 20-year lung cancer-specific survival of participants diagnosed with first primary lung cancer through annual low-dose CT screening. Eligible participants were aged at least 40 years and had current or former cigarette use or had never smoked but had been exposed to secondhand tobacco smoke. Results Among 89 404 I-ELCAP participants, 1257 (1.4%) were diagnosed with a first primary lung cancer (684 male, 573 female; median age, 66 years; IQR, 61-72), with a median smoking history of 43.0 pack-years (IQR, 29.0-60.0). Median follow-up duration was 105 months (IQR, 41-182). The frequency of clinical stage I at pretreatment CT was 81% (1017 of 1257). The 10-year lung cancer-specific survival of 1257 participants was 81% (95% CI: 79, 84) and the 20-year lung cancer-specific survival was 81% (95% CI: 78, 83), and it was 95% (95% CI: 91, 98) for 181 participants with pathologic T1aN0M0 lung cancer. Conclusion The 10-year lung cancer-specific survival of 80% reported in 2006 for I-ELCAP participants enrolled in annual low-dose CT screening and diagnosed with a first primary lung cancer has persisted, as shown by the updated 20-year lung cancer-specific survival for the expanded I-ELCAP cohort. © RSNA, 2023 See also the editorials by Grenier and by Sequist and Olazagasti in this issue.

Ventricular Arrhythmia in Cancer Patients: Mechanisms, Treatment Strategies and Future Avenues.

Cardiovascular disease and cancer are the leading causes of morbidity and mortality in the US. Despite the significant progress made in cancer treatment leading to improved prognosis and survival, ventricular arrhythmias (VA) remain a known cardiovascular complication either exacerbated or induced by the direct and indirect effects of both traditional and novel cancer treatments. Although interruption of cancer treatment because of VA is rarely required, knowledge surrounding this issue is essential for optimising the overall care of patients with cancer. The mechanisms of cancer-therapeutic-induced VA are poorly understood. This review will discuss the ventricular conduction (QRS) and repolarisation abnormalities (QTc prolongation), and VAs associated with cancer therapies, as well as existing strategies for the identification, prevention and management of cancer-treatment-induced VAs.

Lung Cancer Screening in Asbestos-Exposed Populations.

Asbestos exposure is the most important cause of occupational lung cancer mortality. Two large randomized clinical trials in the U.S. and Europe conclusively demonstrate that annual low-dose chest CT (LDCT) scan screening reduces lung cancer mortality. Age and smoking are the chief risk factors tested in LDCT studies, but numerous risk prediction models that incorporate additional lung cancer risk factors have shown excellent performance. The studies of LDCT in asbestos-exposed populations shows favorable results but are variable in design and limited in size and generalizability. Outstanding questions include how to: (1) identify workers appropriate for screening, (2) organize screening programs, (3) inform and motivate people to screen, and (4) incorporate asbestos exposure into LDCT decision-making in clinical practice. Conclusion: Screening workers aged ≥50 years with a history of ≥5 years asbestos exposure (or fewer years given intense exposure) in combination with either (a) a history of smoking at least 10 pack-years with no limit on time since quitting, or (b) a history of asbestos-related fibrosis, chronic lung disease, family history of lung cancer, personal history of cancer, or exposure to multiple workplace lung carcinogens is a reasonable approach to LDCT eligibility, given current knowledge. The promotion of LDCT-based screening among asbestos-exposed workers is an urgent priority.

Lung cancer incidence among world trade center rescue and recovery workers.

BACKGROUND: Many World Trade Center disaster (WTC) rescue and recovery workers (WTC RRWV) were exposed to toxic inhalable particles. The impact of WTC exposures on lung cancer risk is unclear. METHODS: Data from the WTC Health Program General Responders Cohort (WTCGRC) were linked to health information from a large New York City health system to identify incident lung cancer cases. Incidence rates for lung cancer were then calculated. As a comparison group, we created a microsimulation model that generated expected lung cancer incidence rates for a WTC- and occupationally-unexposed cohort with similar characteristics. We also fitted a Poisson regression model to determine specific lung cancer risk factors for WTC RRWV. RESULTS: The incidence of lung cancer for WTC RRWV was 39.5 (95% confidence interval [CI]: 30.7-49.9) per 100,000 person-years. When compared to the simulated unexposed cohort, no significant elevation in incidence was found among WTC RRWV (incidence rate ratio [IRR] 1.34; 95% CI: 0.92-1.96). Predictors of lung cancer incidence included age, smoking intensity, and years since quitting for former smokers. In adjusted models evaluating airway obstruction and individual pre-WTC occupational exposures, only mineral dust work was associated with lung cancer risk (IRR: 2.03; 95% CI: 1.07-3.86). DISCUSSION: In a sample from a large, prospective cohort of WTC RRWV we found a lung cancer incidence rate that was similar to that expected of a WTC- and occupationally-unexposed cohort with similar individual risk profiles. Guideline-concordant lung cancer surveillance and periodic evaluations of population-level lung cancer risk should continue in this group.

Performance of Risk Factor-Based Guidelines and Model-Based Chest CT Lung Cancer Screening in World Trade Center-Exposed Fire Department Rescue/Recovery Workers.

BACKGROUND: Lung cancer is a leading cause of cancer incidence and death in the United States. Risk factor-based guidelines and risk model-based strategies are used to identify patients who could benefit from low-dose chest CT (LDCT) screening. Few studies compare guidelines or models within the same cohort. We evaluate lung cancer screening performance of two risk factor-based guidelines (US Preventive Services Task Force 2014 recommendations [USPSTF-2014] and National Comprehensive Cancer Network Group 2 [NCCN-2]) and two risk model-based strategies, Prostate Lung Colorectal and Ovarian Cancer Screening (PLCOm2012) and the Bach model) in the same occupational cohort. RESEARCH QUESTION: Which risk factor-based guideline or model-based strategy is most accurate in detecting lung cancers in a highly exposed occupational cohort? STUDY DESIGN AND METHODS: Fire Department of City of New York (FDNY) rescue/recovery workers exposed to the September 11, 2001 attacks underwent LDCT lung cancer screening based on smoking history and age. The USPSTF-2014, NCCN-2, PLCOm2012 model, and Bach model were retrospectively applied to determine how many lung cancers were diagnosed using each approach. RESULTS: Among the study population (N = 3,953), 930 underwent a baseline scan that met at least one risk factor or model-based LDCT screening strategy; 73% received annual follow-up scans. Among the 3,953, 63 lung cancers were diagnosed, of which 50 were detected by at least one LDCT screening strategy. The NCCN-2 guideline was the most sensitive (79.4%; 50/63). When compared with NCCN-2, stricter age and smoking criteria reduced sensitivity of the other guidelines/models (USPSTF-2014 [44%], PLCOm2012 [51%], and Bach[46%]). The 13 missed lung cancers were mainly attributable to smoking less and quitting longer than guideline/model eligibility criteria. False-positive rates were similar across all four guidelines/models. INTERPRETATION: In this cohort, our findings support expanding eligibility for LDCT lung cancer screening by lowering smoking history from ≥30 to ≥20 pack-years and age from 55 years to 50 years old. Additional studies are needed to determine its generalizability to other occupational/environmental exposed cohorts.

Screening for Occupational Lung Cancer: An Unprecedented Opportunity.

Selected occupational populations are at the highest risk of lung cancer, because they smoke at increased rates and are concurrently exposed to workplace lung carcinogens. Low-dose computed tomography (CT)-based lung cancer screening has an enormous potential to reduce lung cancer mortality in these populations, as shown both in the lung cancer screening studies in the general population and in studies of workers at high risk of lung cancer. Pulmonologists can play a key role in identifying workers at high risk of lung cancer and ensuring that they are offered annual low-dose CT scans for early lung cancer detection.

Robotics for catheter ablation of cardiac arrhythmias: Current technologies and practical approaches.

Robotic technology has emerged as an important tool to facilitate catheter ablation of arrhythmias. Robotic cardiac electrophysiology technology includes remote magnetic navigation and manual robotic navigation. Robotics can confer advantages with respect to ease of catheter manipulation in anatomically challenging spaces, minimization of fluoroscopic exposure to both patients and operators, and reduction in operator fatigue. This review provides a comprehensive summary of robotic electrophysiology technology, its practical applications and its safety and efficacy for targeting cardiac arrhythmias.

Impact of Aortomitral Continuity Calcification on Need for Permanent Pacemaker After Transcatheter Aortic Valve Replacement.

BACKGROUND: By virtue of its proximity to structures vital to cardiac conduction, aortomitral continuity calcification (AMCC) may help identify patients at highest risk for developing atrioventricular conduction disease requiring permanent pacemaker implantation (PPMI). We aim to determine the association of AMCC and need for PPMI after transcatheter aortic valve replacement. METHODS: Of 614 patients who underwent transcatheter aortic valve replacement (11.8% PPMI rate), we included 136 patients (age 85±8 years, 47% male) without a preexisting intracardiac device or prior valve surgery who underwent preprocedural computed tomography. We analyzed for the presence of AMCC, aortic valve calcification, and mitral annular calcification as well as quantified AMCC and aortic valve calcification score using the Agatston method. We further stratified AMCC score into 3 categories: 0, 1 to 300, and >300. End point was PPMI at 1 month after transcatheter aortic valve replacement. RESULTS: There were 51 (38%) new PPMIs (median time to PPMI, 5 days). Patients who underwent PPMI had a higher prevalence of AMCC than patients without PPMI (69% versus 32%; P<0.0001), as well as higher median AMCC score (263 versus 0; P<0.0001). There was no difference in aortic valve calcification and mitral annular calcification between patients with and without PPMI (all P≥0.09). Patients with AMCC had a 4-fold increase in odds for PPMI compared with those without (adjusted odds ratio, 4.0; P=0.0026). Compared with patients with an AMCC score of 0, patients with an AMCC score >300 had greater than a 5-fold increased odds for PPMI (adjusted odds ratio, 5.7; P=0.0016). CONCLUSIONS: Presence of AMCC, particularly with AMCC score >300, is associated with the need for PPMI after transcatheter aortic valve replacement.

Regional isolation in the right atrium with disruption of intra-atrial conduction after catheter ablation of atrial tachycardia.

BACKGROUND: Ablation of atrial tachycardia (AT) that occurs after cardiac surgery or prior ablation often requires complex lesion sets. In combination with the pre-existing atrial scar, these lesion sets may result in inadvertent intra-atrial conduction block. This study reports the phenomenon of incidental isolation of right atrial (RA) regions that occurs secondary to AT ablation, which in some cases results in profound bradycardia due to sinus exit block. METHODS AND RESULTS: Intracardiac electrograms were examined in consecutive patients who underwent AT ablation in the RA. Cases of localized isolation of the RA were defined as areas that developed electrical dissociation during ablation. Of 132 patients having ablation in both the RA free wall and the cavotricuspid isthmus (CTI), 10 (7.6%) developed unintentional isolation of the lateral RA. Five of these patients had prior mitral valve surgery, comprising 12.2% of all 41 patients with mitral surgery who underwent ablation in the CTI and the RA free wall. All patients with regional isolation had a pre-existing scar in the lateral wall of the RA. In six patients, isolation of the lateral RA resulted in profound bradycardia due to exit block from the peri-sinus node myocardium. CONCLUSIONS: Complex ablation lesions in patients with prior valve surgery, prior ablation, or atrial myopathy may result in unintended localized conduction block in the RA. In some cases, isolation of the lateral RA can result in complete sinus exit block with profound bradycardia requiring pacemaker implantation.

Allergen Sensitization and Asthma Outcomes among World Trade Center Rescue and Recovery Workers.

A large number of World Trade Center (WTC) rescue and recovery workers are affected by asthma. While physical and mental health comorbidities have been associated with poor asthma control in this population, the potential role of allergen sensitization is unknown. This study examined the association of indoor sensitization and exposure as a risk factor for increased asthma morbidity in WTC workers. We used data from a prospective cohort of 331 WTC workers with asthma. Sensitization to indoor allergens was assessed by measurement of antigen-specific serum immunoglobulin E (IgE) levels. We used validated tools to evaluate the exposure to indoor allergens. Asthma morbidity outcomes included level of control (Asthma Control Questionnaire, ACQ), quality of life (Asthma Quality of Life Questionnaire, AQLQ) and acute resource utilization. The prevalence of sensitization to cat, dog, mouse, dust mite, cockroach, and mold allergens were 33%, 21%, 17%, 40%, 17%, and 17%, respectively. Unadjusted and regression analyses showed no significant relationship between sensitization and increased asthma morbidity (p > 0.05 for all comparisons), except for sensitization to Aspergillus Fumigatus, cat and mouse epithelium, which were associated with decreased morbidity.

Outcomes, Costs, and 30-Day Readmissions After Catheter Ablation of Myocardial Infarct-Associated Ventricular Tachycardia in the Real World: Nationwide Readmissions Database 2010 to 2015.

BACKGROUND: Patients undergoing catheter ablation of myocardial infarction-associated ventricular tachycardia (VT) have significant comorbidities that can increase the risks of adverse outcomes. The rates of readmissions after VT ablation are unknown. We sought to examine in-hospital outcomes, costs, and 30-day readmissions after catheter ablation of myocardial infarction-associated VT. METHODS: Using the Nationwide Readmissions Database, we evaluated 4109 admissions for catheter ablation of myocardial infarction-associated VT occurring between 2010 and 2015. On the basis of International Classification of Diseases, Ninth Revision, Clinical Modification and Clinical Classification Software codes, we identified comorbidities, procedural complications, 30-day readmissions, and costs associated with VT ablation. RESULTS: The index admission in-hospital mortality rate and procedural complication rate after VT ablation were 2.7% and 11.5%, respectively. Independent predictors of mortality included pulmonary hypertension, lung disease, obesity, and coagulopathy. Following discharge after VT ablation, the 30-day readmission rate was 19.2% with a median time to readmission of 10.0 days (IQR, 3.8-17.6 days) and an in-hospital mortality rate of 2.9%. Cardiac causes accounted for 74% of readmissions, with VT and congestive heart failure constituting 41% and 14% of all readmissions, respectively. Pulmonary hypertension, congestive heart failure, smoking, chronic pulmonary disease, and prolonged index hospitalization were significant independent predictors of 30-day readmission. After adjustment, 30-day readmissions were associated with a 38.9% increase in cumulative hospitalization costs. CONCLUSIONS: Thirty-day readmissions after catheter ablation of VT occur in nearly 1 out of 5 cases, with the majority of readmissions being caused by recurrent VT or congestive heart failure. Baseline comorbidities are significant predictors of procedural mortality, complications, and readmissions. Strategies to reduce recurrent VT postablation by improving procedural success, optimizing postablation heart failure treatment, and ensuring close postdischarge follow-up may help reduce readmissions and healthcare costs.

Yield of Low-Dose Computerized Tomography Screening for Lung Cancer in High-Risk Workers: The Case of 7189 US Nuclear Weapons Workers.

OBJECTIVES: To determine the lung cancer screening yield and stages in a union-sponsored low-dose computerized tomography scan program for nuclear weapons workers with diverse ages, smoking histories, and occupations. METHODS: We implemented a low-dose computerized tomography program among 7189 nuclear weapons workers in 9 nonmetropolitan US communities during 2000 to 2013. Eligibility criteria included age, smoking, occupation, radiographic asbestos-related fibrosis, and a positive beryllium lymphocyte proliferation test. RESULTS: The proportion with screen-detected lung cancer among smokers aged 50 years or older was 0.83% at baseline and 0.51% on annual scan. Of 80 lung cancers, 59% (n = 47) were stage I, and 10% (n = 8) were stage II. Screening yields of study subpopulations who met the National Lung Screening Trial or the National Comprehensive Cancer Network Group 2 eligibility criteria were similar to those found in the National Lung Screening Trial. CONCLUSIONS: Computerized tomography screening for lung cancer among high-risk workers leads to a favorable yield of early-stage lung cancers. Public Health Implications. Health equity and efficiency dictate that screening high-risk workers for lung cancer should be an important public health priority.

Comparison of robotic magnetic navigation-guided and manual catheter ablation of ventricular arrhythmias arising from the papillary muscles.

Aims: Due to the complex anatomy of the left ventricular (LV) and right ventricular (RV) papillary muscles (PMs), PM ventricular arrhythmias (VAs) can be challenging to target with ablation. We sought to compare the outcomes of robotic magnetic navigation-guided (RMN) ablation and manual ablation of VAs arising from the LV and RV PMs. Methods and results: We evaluated 35 consecutive patients (mean age 65 ± 12 years, 69% male) who underwent catheter ablation of 38 VAs originating from the LV and RV PMs as confirmed by intracardiac echocardiography. Catheter ablation was initially performed using RMN-guidance in 24 (69%) patients and manual guidance in 11 (31%) patients. Demographic and procedural data were recorded and compared between the two groups. The VA sites of origin were mapped to 20 (53%) anterolateral LV PMs, 14 (37%) posteromedial LV PMs, and 4 (11%) RV PMs Acute successful ablation was achieved for 20 (74%) VAs using RMN-guided ablation and 8 (73%) VAs using manual ablation (P = 1.000). Fluoroscopy times were significantly lower among patients undergoing RMN ablation compared to patients undergoing manual ablation [median 7.3, interquartile range (IQR) 3.9-18 vs. 24 (16-44) min; P = 0.005]. Retrograde transaortic approach was used in 1 (4%) RMN patients and 5 (46%) manual patients (P = 0.005). No procedural complications were seen in study patients. Conclusion: Use of an RMN-guided approach to target PM VAs results in comparable success rates seen with manual ablation but with lower fluoroscopy times and decreased use of transaortic retrograde access.

Mechanistic subtypes of focal right ventricular tachycardia.

Idiopathic sustained focal right ventricular tachycardia (VT) is most frequently due to outflow tract (OT) tachycardia. This arrhythmia is recognized by its characteristic ECG pattern and sensitivity to adenosine. However, there are other forms of idiopathic, focal sustained VT that originate from the right ventricle (RV), which are less well appreciated and easily overlooked. This review will identify the characteristic features and electrophysiologic properties of these forms of RV VT, including those originating from the tricuspid annulus, right ventricular papillary muscles, and moderator band as well as variants of classic RVOT tachycardia and those due to microreentry in the presence of preclinical disease. Recognition of these subtypes of focal RV tachycardia should facilitate targeted therapy.