The prognostic value of artificial intelligence to predict cardiac amyloidosis in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement.

Aims: Cardiac amyloidosis (CA) is common in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Cardiac amyloidosis has poor outcomes, and its assessment in all TAVR patients is costly and challenging. Electrocardiogram (ECG) artificial intelligence (AI) algorithms that screen for CA may be useful to identify at-risk patients. Methods and results: In this retrospective analysis of our institutional National Cardiovascular Disease Registry (NCDR)-TAVR database, patients undergoing TAVR between January 2012 and December 2018 were included. Pre-TAVR CA probability was analysed by an ECG AI predictive model, with >50% risk defined as high probability for CA. Univariable and propensity score covariate adjustment analyses using Cox regression were performed to compare clinical outcomes between patients with high CA probability vs. those with low probability at 1-year follow-up after TAVR. Of 1426 patients who underwent TAVR (mean age 81.0 ± 8.5 years, 57.6% male), 349 (24.4%) had high CA probability on pre-procedure ECG. Only 17 (1.2%) had a clinical diagnosis of CA. After multivariable adjustment, high probability of CA by ECG AI algorithm was significantly associated with increased all-cause mortality [hazard ratio (HR) 1.40, 95% confidence interval (CI) 1.01-1.96, P = 0.046] and higher rates of major adverse cardiovascular events (transient ischaemic attack (TIA)/stroke, myocardial infarction, and heart failure hospitalizations] (HR 1.36, 95% CI 1.01-1.82, P = 0.041), driven primarily by heart failure hospitalizations (HR 1.58, 95% CI 1.13-2.20, P = 0.008) at 1-year follow-up. There were no significant differences in TIA/stroke or myocardial infarction. Conclusion: Artificial intelligence applied to pre-TAVR ECGs identifies a subgroup at higher risk of clinical events. These targeted patients may benefit from further diagnostic evaluation for CA.

Electrical storm after left ventricular assist device (LVAD) implantation.

INTRODUCTION: Ventricular tachycardia storm or electrical storm (ES) is a common complication following left ventricular assist device (LVAD) implantation. The factors contributing to ES and outcomes are less studied. The study aimed to determine the factors associated with ES and the probability of survival in patients undergoing LVAD in three tertiary centers over a span of 15 years. METHODS: We performed a retrospective cohort study on all patients who underwent LVAD implantation at the Mayo Clinic (Rochester, Phoenix, and Jacksonville) from January 1, 2006 to December 31, 2020. ES was defined as ≥3 episodes of sustained ventricular tachycardia over a period of 24 h with no identifiable reversible cause. Detailed chart reviews of the electronic health records within the Mayo Clinic and outside medical records were performed. RESULTS: A total of 883 patients who underwent LVAD implantation were included in our study. ES occurred in 7% (n = 61) of patients with a median of 13 days (interquartile range [IQR]: 5-297 days) following surgery. We found 57% of patients (n = 35) developed ES within 30 days, while 43% (n = 26) patients developed ES at a median of 545  (IQR 152-1032) days after surgery. Following ES, 26% of patients died within 1 year. Patients with ES had a significant association with a history of ventricular arrhythmias and implantable cardioverter defibrillator (ICD) shocks before the procedure. ES was significantly associated with reduced survival compared to patients without ES (hazards ratio [HR]: 1.92, 95% CI: 1.39-2.64, p < .001). CONCLUSION: Following LVAD implantation, the rate of ES was 7% with majority of ES occurring within 30 days of LVAD. Risk factors for ES included pre-implant history of ventricular arrhythmias and ICD shock. ES was significantly associated with reduced survival compared to patients without ES.

Long-term outcomes with abandoning versus extracting sterile leads: A 10-year population-based study.

BACKGROUND: Long-term outcomes of sterile lead management strategies of lead abandonment (LA) or transvenous lead extraction (TLE) remain unclear. METHODS: We performed a retrospective study of a population residing in southeastern Minnesota with follow-up at the Mayo Clinic and its health systems. Patients who underwent LA or TLE of 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. 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. 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, 28.6% of patients in the LA cohort who required subsequent extraction did not proceed with the extraction, and among those who proceeded, 60% had clinical success and 40% had a clinical failure. 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 (5.2% vs. 5.3%). There was no difference in 10-year survival probability among the LA group and the TLE group (p = .64). CONCLUSION: An initial lead abandonment strategy was associated with more complicated subsequent extraction procedures compared to patients with an initial transvenous lead extraction strategy. However, there was no difference in 10-year survival probability between both lead management approaches.

Impact of infective versus sterile transvenous lead removal on 30-day outcomes in cardiac implantable electronic devices.

BACKGROUND: Transvenous lead removal (TLR) is associated with increased mortality and morbidity. This study sought to evaluate the impact of TLR on in-hospital mortality and outcomes in patients with and without CIED infection. METHODS: From January 1, 2017, to December 31, 2020, we utilized the nationally representative, all-payer, Nationwide Readmissions Database to assess patients who underwent TLR. We categorized TLR as indicated for infection, if the patient had a diagnosis of bacteremia, sepsis, or endocarditis during the initial admission. Conversely, if none of these conditions were present, TLR was considered sterile. The impact of infective vs sterile indications of TLR on mortality and major adverse events was studied. RESULTS: Out of the total 25,144 patients who underwent TLR, 14,030 (55.8%) received TLR based on sterile indications, while 11,114 (44.2%) received TLR due to device infection, with 40.5% having systemic infection and 59.5% having isolated pocket infection. TLR due to infective indications was associated with a significant in-hospital mortality (5.59% vs 1.13%; OR = 5.16; 95% CI 4.33-6.16; p < 0.001). Moreover, when compared with sterile indications, TLR performed due to device infection was associated with a considerable risk of thromboembolic events including pulmonary embolism and stroke (OR = 3.80; 95% CI 3.23-4.47, p < 0.001). However, there was no significant difference in the conversion to open heart surgery (1.72% vs. 1.47%, p < 0.111), and infection was not an independent predictor of cardiac (OR = 1.12; 95% CI 0.97-1.29) or vascular complications (OR = 1.12; 95% CI 0.73-1.72) between the two groups. CONCLUSION: Higher in-hospital mortality and rates of thromboembolic events associated with TLR resulting from infective indications may warrant further pursuing this diagnosis in patients.

Effect of age on in-hospital outcomes of transvenous lead extraction for infected cardiac implantable electronic device.

BACKGROUND: The real-world data on the safety profile of transvenous lead extraction (TLE) for infected cardiac implantable electronic devices (CIED) among elderly patients is not well-established. This study aimed to evaluate the hospital outcomes between patients of different age groups who underwent TLE for infected CIED. METHOD: Using the Nationwide Readmissions Database, our study included patients aged ≥18 years who underwent TLE for infected CIED between 2017 and 2020. We divided the patients into four groups: Group A. Young (<50 years), Group B. Young intermediate (50-69 years old), Group C. Older intermediate (70-79 years old), and Group D. Octogenarian (≥80 years old). We then analyzed the in-hospital outcome and 30-day readmission between these age groups. RESULTS: A total of 10,928 patients who were admitted for TLE of infected CIED were included in this study: 982 (9.0%) patients in group A, 4,234 (38.7%) patients in group B, 3,204 (29.3%) patients in group C and 2,508 (23.0%) of patients in group D. Our study demonstrated that the risk of early mortality increased with older age (Group B vs. Group A: OR: 1.92, 95% CI: 1.19-3.09, p < .01; Group C vs. Group A: OR: 2.47, 95% CI: 1.51-4.04, p < .01; Group D vs. Group A: OR: 2.82, 95% CI: 1.69-4.72, p < .01). The risk of non-home discharge also increased in elderly groups (Group B vs. Group A: OR: 1.89; 95% CI: 1.52-2.36; p < .01; Group C vs. Group A: OR: 2.82; 95% CI 2.24-3.56; p < .01; Group D vs. Group A: OR: 4.16; 95% CI: 3.28-5.28; p < .01). There was no significant difference in hospitalization length and 30-day readmission between different age groups. Apart from a higher rate of open heart surgery in group A, the procedural complications were comparable between these age groups. CONCLUSION: Elderly patients had worse in-hospital outcomes in early mortality and non-home discharge following the TLE for infected CIED. There was no significant difference between elderly and non-elderly groups in prolonged hospital stay and 30-day readmission. Elderly patients did not have a higher risk of procedural complications.

Thirty-day readmission after catheter ablation for ventricular tachycardia: associated factors and outcomes.

BACKGROUND: Patients with ventricular tachycardia (VT) who require VT ablation are at high risk for readmission. This study aimed to identify the causes and outcomes of 30-day readmission after VT ablation and to analyze the predictors of recurrent VT that required rehospitalization. METHODS: Using the Nationwide Readmission Database, our study included patients aged ≥ 18 years who underwent VT catheter ablation between 2017 and 2020. Based on the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM), we identified the causes of 30-day readmission by organ systems and analyzed their outcomes. Additional analysis was performed to determine the independent predictors of 30-day readmission for recurrent VT. RESULTS: Of the 4228 patients who underwent VT ablation, 14.2% were readmitted within 30 days of the procedure. The most common cause of readmission was cardiac events (73.6%). Among the cardiac-related readmissions, recurrent VT (47.7%) and congestive heart failure (CHF) (12.9%) were the most common etiologies. Among the readmissions, patients readmitted for CHF had the highest rate of readmission mortality (9.2%). Of the patients readmitted within 30 days of the procedure, 278 patients (6.8%) were readmitted for recurrent VT. Via multivariable analysis, CHF (OR: 1.97; 95% CI: 1.12-3.47; P = 0.02) and non-elective index admissions (OR: 1.63; 95% CI: 1.04-2.55; P = 0.03) were identified as the independent predictors predictive of 30-day readmissions for recurrent VT. CONCLUSIONS: Recurrent VT was the most common cause of readmission after the VT ablation procedure, and CHF and non-elective index admissions were the significant predictors of these early readmissions. Readmission due to CHF had the highest mortality rate during readmission.

Adverse events in cryoballoon ablation for pulmonary vein isolation: Insight from the Food and Drug Administration Manufacturer and User Facility Device Experience.

Background: Real-world clinical data on the adverse events related to the use of cryoballoon catheter for pulmonary vein isolation remains limited. Objective: To report and describe the adverse events related to the use of Artic Front cryoballoon catheters (Arctic Front, Arctic Front Advance, and Arctic Front Advance Pro) reported in the Food and Drug Administration's (FDA) Manufacturers and User Defined Experience (MAUDE) database. Methods: We reviewed all the adverse events reported to the FDA MAUDE database over a 10.7-year study period from January 01, 2011 to September 31, 2021. All events were independently reviewed by two physicians. Results: During the study period, a total of 320 procedural-related adverse events reported in the MAUDE database were identified. The most common adverse event was transient or persistent phrenic nerve palsy (PNP), accounting for 48% of all events. This was followed by cardiac perforation (15%), pulmonary vein stenosis (8%), transient ischemic attack or stroke (6%), vascular injury (4%), transient or persistent ST-elevation myocardial infarction (3%), hemoptysis (2%), pericarditis (2%), and esophageal ulcer or fistula (1%). There were six reported intra-procedural death events as a result of cardiac perforation. Conclusion: The two most common procedural adverse events associated with cryoballoon ablation were PNP and cardiac perforation. All cases of procedural mortality were due to cardiac perforation.

A Systematic Review of Short-Term Outcomes of Leadless Pacemaker Implantation After Transvenous Lead Removal of Infected Cardiac Implantable Electronic Device.

The outcomes of leadless pacemaker (LP) implantation after transvenous lead removal (TLR) of infected cardiac implantable electronic devices (CIEDs) are not well-established. This study sought to describe the outcomes of LP implantation after TLR of infected CIED. We conducted a literature search using PubMed and Embase for a combination of terms including LP implantation, transvenous lead extraction, TLR, transvenous lead explant, infected CIED, infected pacemaker, and infected implantable cardioverter defibrillator. The inclusion criterion was LP implantation after TLR of infected CIED. The exclusion criterion was TLR for noninfectious reasons. Study end points included procedural complications and LP infection during follow-up. Of 132 publications reviewed, 13 studies with a total of 253 patients (74 ± 14 years of age, 174 [69%] males) were included. The most common indication of the initial device implantations was a high-degree atrioventricular block (n = 100 of 253, 39.5%). Of the 253 patients included, 105 patients (41.5%) underwent concomitant LP implantation during the TLR procedure, and 36 patients (14.2%) had temporary transvenous pacing as a bridge from TLR to LP implantation. Of the 148 patients with data on the type of CIED infection, 56.8% had systemic CIED infection and 43.2% had isolated pocket infection. Staphylococcus aureus was the most common causative organism in 33% of the reported patients. The LP was implanted an average of 5.4 ± 10.7 days after TLR of infected CIED. During the LP implantation, 1 patient (0.4%) had unsuccessful implantation because of an intraprocedural complication requiring sternotomy. After LP implantation, 2 patients (0.8%) developed groin hematoma, 2 patients (0.8%) developed femoral arteriovenous fistula, and 1 patient (0.4%) developed pericardial effusion requiring pericardiocentesis. During a mean follow-up of 11.3 ± 10.6 months, 3 patients (1.2%) developed pacemaker syndrome, 1 patient (0.4%) developed acute on chronic heart failure exacerbation, and only 1 patient (0.4%) developed LP-related infection requiring LP retrieval. This study suggests that LP implant is feasible and safe after removal of infected CIED with cumulative adverse events at 4% and a reinfection rate of 0.4%. Large prospective studies are needed to better evaluate the best timing of LP implantation after TLR of an infected CIED.

Causes of Early Mortality After Catheter Ablation of Atrial Fibrillation.

BACKGROUND: Recognition of the causes of early mortality after atrial fibrillation (AF) catheter ablation is essential for the improvement of patient safety. This study sought to determine the causes of early mortality (≤90 days) after AF ablation. METHODS: We performed a retrospective analysis of AF ablation from January 1, 2013, to December 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a comprehensive chart review of the electronic health record from within the Mayo Clinic system and outside records when available. RESULTS: A total of 6723 patients were included in the study. The 90-day all-cause mortality rate was 0.22% (n=15). Among all 90-day deaths, majority of the deaths (73.3%) did not have a direct relationship with the procedure. Sudden death was the most common cause of early death (20%), followed by peri-procedural stroke (13%), respiratory failure (13%), atrioesophageal fistula (13%), infection (7%), heart failure (7%), and traumatic brain injury (7%). The 90-day mortality rate directly due to AF ablation procedural complications was 0.06% (n=4). CONCLUSIONS: AF ablation procedure has a 90-day mortality of 0.22%, and the most common cause of early mortality was sudden death. The majority (73.3%) of early mortality was not directly associated with a procedural complication, and the mortality rate due to complications associated with the AF ablation procedure was low at 0.06%. Further studies are required to investigate causes and risk factors associated with sudden death in this patient population.

Incidentally Discovered Right Atrial Mass: A Rare and Unexpected Etiology.

Primary cardiac sarcoma is a rare type of intracardiac mass. This report describes a patient with atrial flutter who had a new right atrial mass incidentally discovered on transesophageal echocardiography. A thrombus was suspected based on radiographic appearance, but there was minimal change with anticoagulation. The mass was resected and found to be an undifferentiated pleomorphic cardiac sarcoma, an uncommon sub-type within the already rare category of primary cardiac neoplasms. This report highlights the importance of considering primary malignancy and thoroughly correlating radiographic and clinical evidence during the diagnostic workup of patients with intracardiac masses.

Causes of Early Mortality After Ventricular Tachycardia Ablation in Patients With Reduced Ejection Fraction.

BACKGROUND: Recognition of the causes of early mortality after ventricular tachycardia (VT) ablation in patients with reduced left ventricular ejection fraction (LVEF) is an essential step toward improving postprocedural outcomes. OBJECTIVES: This study sought to determine the causes of early mortality (≤30 days) after VT ablation in patients with reduced LVEF and to understand further the circumstances surrounding death after the procedure. METHODS: We performed a retrospective analysis of all patients undergoing VT ablation in patients with reduced LVEF from January 1, 2013, to November 10, 2021, at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a detailed chart review of the electronic health record within the Mayo Clinic system and outside records. RESULTS: A total of 503 patients (mean age 63 ± 13 years, 11.2% women) with ejection fraction <50% were included in the study. The 30-day all-cause mortality rate was 5.0% (n = 25), and the mortality rate due to a procedural complication was 0.4%. Among all 30-day deaths, recurrent VT was the most common primary cause of death (44.0%). This was followed by decompensated heart failure (28.0%), procedure-related death (8.0%), cerebrovascular accident (4.0%), and infection (4.0%). Most patients (91.0%) who died from VT had VT recurrence within 3 days of the ablation. The average PAINESD score among early mortality was 20 ± 4, and 92.0% of these patients (n = 23) had a score >15. Significant predictors of early mortality included nonischemic cardiomyopathy, lower LVEF, electrical storm, and ventricular fibrillation. CONCLUSIONS: The overall early mortality (≤30 days) rate after catheter ablation of VT in patients with reduced LVEF was 5.0%, but the death rate directly due to a procedural complication was only 0.4%. The most common cause of death was recurrent VT, followed by heart failure. Further research into ablation strategies is vital to improving the safety, efficacy, and durability of VT ablation.

Causes of Early Mortality After Transvenous Lead Removal.

BACKGROUND: Recognition of the causes of early mortality (≤30 days) after transvenous lead removal (TLR) is an essential step for the development of quality improvement programs. OBJECTIVES: This study sought to determine the causes of early mortality after TLR and to further understand the circumstances surrounding death after TLR. METHODS: A retrospective analysis was performed of all patients undergoing TLR from January 1, 2001, to January 1, 2021, at the Mayo Clinic (Rochester, Minnesota; Phoenix, Arizona; and Jacksonville, Florida). 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% (n = 69). 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%. One-third of deaths (33%) occurred after discharge from the index hospitalization; among these, 43% were readmitted before their death, 35% died at home or at a nursing facility, and 22% were discharged on comfort care and died in hospice. The main reasons for readmission before 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 increased emphasis on postprocedure management of infection and heart failure to reduce postoperative mortality, including after hospital discharge.

Influence of endurance sports on atrial fibrillation ablation outcomes.

Objectives: We aimed to investigate the outcomes of pulmonary vein isolation in athletes. Methods: We retrospectively identified endurance athletes who underwent catheter ablation at our institution (2004-2018). Endurance athletes were defined as participating in competitive athletics for at least 1500 lifetime hours in sports at the IB or IIA Bethesda classification or higher. Primary endpoints were freedom from atrial arrhythmias at 12, 24, and 36 months after the procedure. Secondary endpoints were defined as qualitative improvement in symptoms allowing athletes to return to their previous level of activity. Athletes were compared with a control group of nonathletes in a 3-to-1 matched analysis by age and sex. Results: A total of 39 endurance athletes who underwent catheter ablation were identified during the study period. At 12 months, there was no difference in treatment outcomes for athletes versus nonathletes (relative risk [RR], 1.06; 95% CI, 0.92-1.22; p = .40). Freedom from atrial arrhythmias was 35% less likely in athletes than nonathletes at 24 months (RR, 0.65; 95% CI, 0.50-0.83; p < .001) and 42% less likely at 36 months (RR, 0.58; 95% CI, 0.41-0.79; p < .001). Overall, 77% of the athletes were able to return to their previous level of activity following catheter ablation. Conclusion: Endurance athletes with atrial fibrillation appear to have higher rates of atrial arrhythmia recurrence than nonathletes after catheter ablation, with higher rates of atypical flutter. The majority of athletes were able to return to their previous level of activity after ablation.

Optogenetic Control of Engrafted Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes in Live Mice: A Proof-of-Concept Study.

Background: Cellular transplantation has emerged as promising approach for treating cardiac diseases. However, a poor engraftment rate limits our understanding on how transplanted cardiomyocytes contribute to cardiac function in the recipient's heart. Methods: The CRISPR/Cas9 technique was employed for stable and constitutive gene expression in human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs). Myocardial infarction was induced in adult immunodeficient mice, followed by intramyocardial injection of hiPSC-CMs expressing either CCND2/channelrhodopsin 2 (hiPSC-CCND2OE/ChR2OECMs) or CCND2/luciferase (hiPSC-CCND2OE/LuciOECMs). Six months later, hemodynamics and intramural electrocardiogram were recorded upon blue light illuminations in anesthetized, open-chest mice. Results: Blue light resets automaticity of spontaneously beating hiPSC-CCND2OE/ChR2OECMs in culture, but not that of hiPSC-CCND2OE/LuciOECMs. Response to blue light was also observed in mice carrying large (>106 cells) intracardiac grafts of hiPSC-CCND2OE/ChR2OECM but not in mice carrying hiPSC-CCND2OE/LuciOECMs. The former exhibited single premature ventricular contractions upon light illumination or ventricular quadrigeminy upon second-long illuminations. At the onset of premature ventricular contractions, maximal systolic ventricular pressure decreased while ventricular volume rose concomitantly. Light-induced changes reversed upon resumption of sinus rhythm. Conclusions: We established an in vivo model for optogenetic-based modulation of the excitability of donor cardiomyocytes in a functional, reversible, and localized manner. This approach holds unique value for studying electromechanical coupling and molecular interactions between donor cardiomyocytes and recipient hearts in live animals.

A real-world experience of atrioventricular synchronous pacing with leadless ventricular pacemakers.

AIMS: The MicraTM transcatheter pacing system (TPS) (Medtronic) is the only leadless pacemaker that promotes atrioventricular (AV) synchrony via accelerometer-based atrial sensing. Data regarding the real-world experience with this novel system are scarce. We sought to characterize patients undergoing MicraTM -AV implants, describe percentage AV synchrony achieved, and analyze the causes for suboptimal AV synchrony. METHODS: In this retrospective cohort study, electronic medical records from 56 consecutive patients undergoing MicraTM -AV implants at the Mayo Clinic sites in Minnesota, Florida, and Arizona with a minimum follow-up of 3 months were reviewed. Demographic data, comorbidities, echocardiographic data, and clinical outcomes were compared among patients with and without atrial synchronous ventricular pacing (AsVP) ≥ 70%. RESULTS: Sixty-five percent of patients achieved AsVP ≥ 70%. Patients with adequate AsVP had smaller body mass indices, a lower proportion of congestive heart failure, and prior cardiac surgery. Echocardiographic parameters and procedural characteristics were similar across the two groups. Active device troubleshooting was associated with higher AsVP. The likely reasons for low AsVP were small A4-wave amplitude, high ventricular pacing burden, and inadequate device reprogramming. Importantly, in patients with low AsVP, subjective clinical worsening was not noted during follow-up. CONCLUSION: With the increasing popularity of leadless pacemakers, it is paramount for device implanting teams to be familiar with common predictors of AV synchrony and troubleshooting with MicraTM -AV devices.

Safety of magnetic resonance imaging in patients with cardiac implantable electronic devices with generator and lead(s) brand mismatch.

Magnetic resonance imaging (MRI) is a valuable imaging modality for the assessment of both cardiac and non-cardiac structures. With a growing population of patients with cardiovascular implantable electronic devices (CIEDs), 50%-75% of these patients will need an MRI. MRI-conditional CIEDs have demonstrated safety of MRI scanning with such devices, yet non-conditional devices such as hybrid CIEDs which have generator and lead brand mismatch may pose a safety risk. In this retrospective study, we examined the outcomes of patients with hybrid CIEDs undergoing MRI compared to those patients with non-hybrid CIEDs. A total of 349 patients were included, of which 24 patients (7%) had hybrid CIEDs. The primary endpoint was the safety of MRI for patients with hybrid CIEDs as compared to those with non-hybrid devices, measured by the rate of adverse events, including death, lead or generator failure needing immediate replacement, loss of capture, new onset arrhythmia, or power-on reset. Secondary endpoints consisted of pre- and post-MRI changes of decreased P-wave or R-wave sensing by ≥50%, changes in pacing lead impedance by ≥50 ohms, increase in pacing thresholds by ≥ 0.5 V at 0.4 ms, and decreasing battery voltage of ≥ 0.04 V. The primary endpoint of any adverse reaction was present in 1 (4.2%) patient with a hybrid device, and consistent of atrial tachyarrhythmia, and in 10 (3.1%) patients with a non-hybrid device, and consisted of self-limited atrial and non-sustained ventricular arrhythmias; this was not statistically significant. No significant differences were found in the secondary endpoints. This study demonstrates that MRI in patients with hybrid CIEDs does not result in increased patient risk or significant device changes when compared to those patients who underwent MRI with non-hybrid CIEDs.

Coexisting fascicular ventricular tachycardia and papillary muscle ventricular tachycardia in the setting of coronary artery disease in a master athlete.

A 73-year old male developed syncope during a bicycle race. Exercise stress testing demonstrated non-sustained ventricular tachycardia (NSVT) and ischemic changes. Coronary angiography revealed a 99% occluded right coronary artery which was stented; repeat stress testing demonstrated normal perfusion and NSVT. An electrophysiology study demonstrated left posterior fascicular ventricular tachycardia, which was ablated at two lower turnaround points. NSVT was observed during subsequent stress testing, prompting a repeat electrophysiology study. The inferoseptum and inferior wall were extensively ablated, along with a posteromedial papillary muscle premature ventricular complex. With no further demonstrable NSVT, the patient was cleared to return to competition.

Use of Flecainide in Stable Coronary Artery Disease: An Analysis of Its Safety in Both Nonobstructive and Obstructive Coronary Artery Disease.

BACKGROUND: Flecainide is a class IC antiarrhythmic drug that is contraindicated in patients who have a history of myocardial infarction, but its effect on mortality and risk of proarrhythmia in patients with stable obstructive and nonobstructive epicardial coronary artery disease (CAD) has not been assessed. OBJECTIVE: We sought to compare the safety of flecainide administration in patients who had angiographic evidence of either no or minimal CAD versus nonobstructive CAD, and those who underwent nuclear stress testing with perfusion defects versus those without perfusion defects. METHODS: We conducted a retrospective chart review of 348 patients who were treated with flecainide for at least 1 year duration and underwent evaluation for CAD with coronary angiography or myocardial perfusion imaging (MPI) stress testing within 3 months of initiating flecainide. We compared overall mortality and proarrhythmia between varying levels of CAD and perfusion defects. RESULTS: There was a similar 10-year survival between those with no or minimal CAD, nonobstructive CAD, and obstructive CAD (p = 0.6). Additionally, there was no difference in arrhythmia burden, including sustained ventricular tachycardias or frequent premature ventricular contractions (> 5% daily burden; p = 0.25). There was also no increase in mortality among those who had reversible perfusion defects >0% compared with those without, among subjects who underwent MPI (p = 0.14). On subgroup analysis, there was no increased risk in all-cause mortality with any specific coronary artery involvement, or with obstructive multivessel CAD (p = 0.89). CONCLUSION: Flecainide use is not associated with an increase in either all-cause mortality or ventricular arrhythmias in low-risk patients with stable nonobstructive CAD.