Sorajja, Dan

Background: Long-term outcomes of lead management strategies of lead abandonment (LA) or transvenous lead extraction (TLE) during cardiac implantable electronic devices (CIED) procedures requiring lead addition or replacement remain unclear. Hypothesis: We hypothesized that there is no difference in long-term (10-year) outcomes of LA versus TLE during CIED procedures requiring lead addition. Methods: We performed a retrospective cohort study of a population residing in seven adjacent counties of southeastern Minnesota with follow-up at the Mayo Clinic and its health systems. Patients who underwent LA or TLE for sterile leads from January 1, 2000, to January 1, 2011, and had follow-up for at least 10-years or until their death were included. Outcomes were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system. Results: A total of 172 patients were included in the study with 153 patients who underwent LA and 19 who underwent TLE for sterile leads. In long-term follow-up, indications for subsequent lead extraction arose in 9.1% (n=14) of patients with initial LA and 5.3% (n=1) in patients with initial TLE, after an average of 7-years. Moreover, out of 14 patients, who required secondary extraction in the LA cohort, 28.6% did not proceed with the extraction. Of the remaining 10 patients, 60% had clinical success and 40% had a clinical failure with the extraction. Subsequent device upgrades or revisions were performed in 18.3% of patients in the LA group and 31.6% in the TLE group, with no significant differences in procedural challenges such as requiring balloon venoplasty or serial dilation (5.2% vs. 5.3%, P=1.0). There was no difference in 10-year survival probability among LA group and TLE group (P=0.64). Conclusion: Indications for subsequent extraction arose in 9.1% of patients with the initial LA approach for sterile leads after an average of 7.3 years and 28.6% did not proceed with the extraction. Of the patients who underwent the subsequent extraction, 60% had clinical success and 40% had a clinical failure. There was no difference in 10-year survival probability between patients with the initial LA approach or TLE approach.

Background: Recognition of the infectious characteristics among the sepsis-related early mortality after transvenous lead removal (TLR) is an essential step to improving patient outcomes. Objective: This study sought to understand the infectious characteristic and circumstances among the sepsis-related early mortality after TLR. Methods: We performed a retrospective analysis of all patients undergoing TLR from January 1, 2001, to January 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Patient details were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system and outside records when available. Results: A total of 2,319 patients were included in the study. The overall 30-day sepsis-related mortality rate was 1.25% (n=29). Among the sepsis-related deaths, 24 patients (83%) had systemic cardiac implantable electronic device (CIED) infection, and 4 patients (14%) initially had isolated pocket infection. The average time from admission to TLR was 11 days. MSSA was the most common organism (n=8, 28%), and this was followed by MRSA (n=4, 14%) and Candida (n=3, 10%). Twenty of these patients (69%) had vegetation on the echocardiogram: vegetation on lead only in 9 patients, vegetation on both valve and lead in 8 patients, and vegetation on valve only in 3 patients. Among valvular vegetations, 5 patients had tricuspid valve vegetations, 3 patients had aortic valve vegetations, 2 patients had mitral valve vegetations, and 1 patient had both mitral and aortic valve vegetation. The average size of vegetation was 1.3±0.8 x 1.1±0.6 cm. Conclusions: The 30-day sepsis-related mortality rate was 1.25%. Among the sepsis-related early deaths, MSSA was the most common organism, and more than two-thirds (69%) of the patients had vegetations on cardiac imaging. This highlights the importance of further research to improve the infection outcome in TLR patients.

Background: Recognition of the causes of early mortality after transvenous lead removal (TLR) is an essential step for the development of quality improvement programs. Objective: This study sought to determine the causes of early mortality after TLR and to further understand the circumstances surrounding death after TLR. Methods: We performed a retrospective analysis of all patients undergoing TLR from January 1, 2001, to January 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system and outside records when available. The causes of death were further characterized based on whether it was related to the TLR procedure. Results: A total of 2,319 patients were included in the study. The overall 30-day all-cause mortality rate was 3%. Among all 30-day deaths, infection was the most common primary cause of death (42%). This was followed by decompensated heart failure (17%), procedure-related death (10%), sudden cardiac arrest (7%), and respiratory failure (6%). The 30-day mortality rate directly due to complications associated with the TLR procedure was 0.3% due to vascular tear and cardiac perforation. A third of deaths (33%) occurred after discharge from index hospitalization, among which 43% were readmitted before their death, 35% died at home or a nursing facility, and 22% were discharged on comfort care and died in hospice. The main reasons for readmission prior to death were sepsis and decompensated heart failure. Conclusions: The majority (90%) of 30-day mortality after TLR was not due to complications associated with TLR procedures. The primary causes were infection and decompensated heart failure. This highlights the importance of further research to reduce postoperative mortality from these factors, including deaths after hospital discharge.

AbstractBackgroundThe incidence and impact of noise in a subcutaneous implantable cardioverter defibrillator (S‐ICD) after left ventricular assist device (LVAD) implantation is not well established.MethodsWe performed a retrospective study of patients implanted with LVAD and with a pre‐existing S‐ICD between January 2005 and December 2020 at the three Mayo Clinic centers (Minnesota, Arizona, and Florida).ResultsOf the 908 LVAD patients, a pre‐existing S‐ICD was present in 9 patients (mean age 49.1 ± 13.7 years, 66.7% males), 100% with Boston Scientific third‐generation EMBLEM MRI S‐ICD, 11% with HeartMate II (HM II), 44% with HeartMate 3 (HM 3), and 44% with HeartWare (HW) LVAD. The incidence of noise from LVAD‐related electromagnetic interference (EMI) was 33% and was only seen with HM 3 LVAD. Multiple measures attempted to resolve noise, including using alternative S‐ICD sensing vector, adjusting S‐ICD time zone, and increasing LVAD pump speed, were unsuccessful, necessitating S‐ICD device therapies to be turned off permanently.ConclusionsThe incidence of LVAD‐related S‐ICD noise is high in patients with concomitant LVAD and S‐ICD with significant impact on device function. As conservative management failed to resolve the EMI, the S‐ICDs had to be programmed off to avoid inappropriate shocks. This study highlights the importance of awareness of LVAD‐SICD device interference and the need to improve S‐ICD detection algorithms to eliminate noise.

Abstract Introduction Atrial fibrillation (AF) is the most common arrhythmia worldwide. The role of the pulmonary veins (PV) in its' pathogenesis has been well described, as have the most frequently seen anatomical variants of these veins. Prior studies have shown conflicting evidence on the potential association of PV variants and incidence of AF. We sought to reassess this association. Methods We conducted a retrospective case-control study of patients with AF (cases) and without AF (control group) undergoing cardiac CT imaging. We documented patient characteristics and cardiac anatomical features including PV variants, LV ejection fraction (EF) and left atrial (LA) volume/diameter. Results 295 patients were included: 194 with AF and 101 without. 71% of AF cases were male. We showed a numerical difference for PV variants between the AF and control group that was not statistically significant (48.5% and 39.6%, p=0.15). The overall incidence of PV variants was higher than in previous studies. A significant association was identified between left atrial appendage (LAA) morphology and incidence of AF. Conclusion The suggested association between PV anatomical variants and the pathogenesis of AF may not be as clear-cut as previously thought. Our study is one of the largest of its kind and provides conflicting evidence with prior studies in this area. An improved understanding of the complex pathophysiology of AF and its relation to the pulmonary veins may help to guide future preventative and therapeutic strategies. Funding Acknowledgement Type of funding sources: None.

Sinus tachycardia (ST) is ubiquitous, but its presence outside of normal physiological triggers in otherwise healthy individuals remains a commonly encountered phenomenon in medical practice. In many cases, ST can be readily explained by a current medical condition that precipitates an increase in the sinus rate, but ST at rest without physiological triggers may also represent a spectrum of normal. In other cases, ST may not have an easily explainable cause but may represent serious underlying pathology and can be associated with intolerable symptoms. The classification of ST, consideration of possible etiologies, as well as the decisions of when and how to intervene can be difficult. ST can be classified as secondary to a specific, usually treatable, medical condition (eg, pulmonary embolism, anemia, infection, or hyperthyroidism) or be related to several incompletely defined conditions (eg, inappropriate ST, postural tachycardia syndrome, mast cell disorder, or post-COVID syndrome). While cardiologists and cardiac electrophysiologists often evaluate patients with symptoms associated with persistent or paroxysmal ST, an optimal approach remains uncertain. Due to the many possible conditions associated with ST, and an overlap in medical specialists who see these patients, the inclusion of experts in different fields is essential for a more comprehensive understanding. This article is unique in that it was composed by international experts in Neurology, Psychology, Autonomic Medicine, Allergy and Immunology, Exercise Physiology, Pulmonology and Critical Care Medicine, Endocrinology, Cardiology, and Cardiac Electrophysiology in the hope that it will facilitate a more complete understanding and thereby result in the better care of patients with ST.

Abstract Background Fever, alcohol, and sodium channel blockers can unmask Brugada pattern and may also induce arrhythmias in Brugada syndrome. We report a case of unmasked Type-1 Brugada pattern presenting with ventricular fibrillation that was induced by a tetrahydrocannabinol vaping. Case summary A 48-year-old male with a past medical history of hypertension treated with hydrochlorothiazide and back pain controlled with tetrahydrocannabinol vaping presented with sudden cardiac arrest from ventricular fibrillation, which was terminated with defibrillation. Electrocardiogram after resuscitation showed a new Type-1 Brugada pattern compared to a previous normal baseline electrocardiogram. Echocardiography and coronary angiogram were unremarkable. Complete blood count and chemistries were unremarkable except for mild hypokalaemia (K = 3.3 mmol/L). After correction of the hypokalaemia, the Type-1 Brugada pattern persisted. Urine drug screen was positive for tetrahydrocannabinol (60 ng/mL). Genetic testing was negative for inherited arrhythmic disease and cardiomyopathy gene panels. Discussion The patient’s type-1 Brugada pattern and ventricular fibrillation were likely induced by vaping tetrahydrocannabinol. He underwent secondary prevention with an implantable cardioverter-defibrillator. He abstains from cannabis and Type-1 Brugada pattern is normalized. There was no arrhythmic event at his 18-month follow-up appointment with abstinence from tetrahydrocannabinol.

Abstract Funding Acknowledgements Type of funding sources: None. Background The prevalence of Type-1 Brugada pattern in Caucasians and Asians have been estimated to be 20 and 180 per 100,000. However, the prevalence of Type-1 Brugada pattern in African Americans has never been studied. Purpose This study aims to identify the prevalence of Type-1 Brugada pattern in African Americans. Methods Medical records of African American patients ages 18 years old or older with at least one 12-lead electrocardiogram (ECG) performed at 16 hospitals from 5 states in a single healthcare system between January 1, 2011 to December 31, 2020 were included. The search engine software was used to identify patients with keywords (Brugada pattern, Brugada ECG, Brugada Type-1, or Brugada syndrome) documented in the electronic medical record. The 12-lead ECGs were retrospectively analyzed by 2 cardiologists. Any inconsistencies were reviewed by a third cardiac electrophysiologist. Type-1 Brugada pattern was diagnosed according to the recent Heart Rhythm Society Expert Consensus Statement. Results Among 43,116 African American patients, (46.9% males), 6 patients (mean age 44.8±13.9 years, 100% males) had Type-1 Brugada pattern documented on at least one 12-lead ECG. The prevalence of Type-1 Brugada pattern in this large patient population of African American was 13.9 per 100,000. None of the patients had major arrhythmic event at 6.7±4.7 years follow-up. Conclusions The prevalence of Type-1 Brugada pattern in African American is lower than Caucasian and Asian populations. The risk of major arrhythmic event of Type-1 Brugada pattern in African American appears to be low; however longer follow-up data is needed.

Introduction: Catheter ablation of the arrhythmogenic substrate reduces the recurrence of ventricular tachycardia (VT) in patients with ischemic cardiomyopathy and implantable cardioverter-defibrillator (ICD). However, the all-cause mortality benefit in this population is unclear. Hypothesis: Prophylactic ablation of the arrhythmogenic substrate decreases all-cause mortality and prevents the recurrence of VT/ventricular fibrillation (VF) in patients with ischemic cardiomyopathy. Methods: We searched the MEDLINE and EMBASE databases from inception through May 2021. We included randomized controlled trials that compared all-cause mortality and ventricular arrhythmia recurrence in patients with ischemic cardiomyopathy who underwent ICD implantation with and without prophylactic ablation. The data from each study was combined using a fixed effects model to calculate the hazard ratio and 95% confidence interval (CI). Results: Four randomized controlled trials during 2007-2020 involving 505 patients (249 patients with and 256 patients without prophylactic VT ablation) were included in our meta-analysis. Compared with control, prophylactic VT ablation did not decrease the all-cause mortality (pooled hazard ratio = 0.94, 95% CI 0.54-1.63, p = 0.818, I2 = 5.8%). However, prophylactic VT ablation significantly decreased appropriate ICD therapy (pooled hazard ratio = 0.58, 95% CI 0.41-0.82, p = 0.002, I 2 = 26.1%) and VT/VF recurrence (pooled hazard ratio = 0.70, 95% CI 0.52-0.93, p = 0.015, I 2 = 0.0%). Conclusions: Prophylactic VT ablation in patients with ischemic cardiomyopathy did not decrease all-cause mortality; however, it did lead to decreased appropriate ICD therapy and VT/VF recurrence.