Trends, Burden, and Impact of Arrhythmias on Cardiac Transplant Recipients: A 16-year Nationwide Study.

Orthotopic heart transplantation is the most effective long-term therapy for end-stage heart disease. Denervation with the loss of autonomic modulation, vasculopathy, utilization of immunosuppressant drugs, and allograft rejection may result in an increased prevalence of arrhythmias in transplanted hearts. We aim to describe the trends, distribution, and the clinical impact of arrhythmias in patients with transplanted hearts. We queried the National Inpatient Sample with administrative codes for cardiac transplant patients using procedure ICD-9-CM codes 37.5 and 33.6. Arrhythmias were extracted using validated ICD-9-CM codes. Statistical Analysis System (SAS) version 9.4 was used for analysis. There were a total of 30,020 hospitalizations of heart transplant recipients between 1999 and 2014 in the United States of which 1,6342 (54.4%) had an arrhythmia. The frequency of total arrhythmias increased from 53.6% (n=1,158) in 1999 to 67.3% (n=1,575) in 2014. Transplant patients with arrythmias was not associated with significantly higher inpatient mortality (7.72% vs 6.90%, P = 0.225). The most common arrythmia was atrial fibrillation ([AF]26.83%) followed by ventricular tachycardia (22.86%). Trends in mortality associated with arrhythmias following heart transplant has been decreasing from 12.3% in 1999 to 8.9% in 2014 (P = 0.04). Subgroup analysis of ventricular arrythmias (VA) following heart transplant were associated with increased mortality (8.61% vs 6.94%, P = 0.0229). Over half of patients develop 1 or more cardiac arrhythmia after heart transplant. There is an increasing secular trend in the frequency of arrhythmias post cardiac transplant with atrial fibrillation determined to be the most common arrhythmia.

Diagnosing a wide complex tachycardia using basic electrophysiologic properties of the cardiac conduction system.

65-year-old man with a history of coronary artery disease s/p percutaneous coronary intervention to the left anterior descending artery and atrial fibrillation s/p recent (<3 months) pulmonary vein isolation presented to the emergency department with symptoms of palpitations for 1 day after admittedly forgetting to take his medications found to be in a wide complex tachycardia. We discuss a stepwise approach using properties of the conduction system to diagnose the patient's tachycardia.

Trends, Prevalence, and Outcomes of Sudden Cardiac Arrest Post Cardiac Transplant: A Nationwide 16-Year Study.

Heart transplantation is the most effective long-term therapy for end-stage heart disease. There is limited data related to sudden cardiac arrest (SCA) in postheart transplant recipients. We aimed to describe the trends, and rate of SCA following heart transplantation and thereby identify clinical predictors as well as outcomes of SCA in patients post-transplant. We queried the National Inpatient Sample (NIS) with administrative codes for SCA and heart transplant. We assessed baseline differences between SCA and non-SCA admissions, with hazard ratios adjusted for age, gender, CCI, and race. Multivariable logistic regression models were generated to identify the independent predictors for SCA. There was a total of 30,020 hospitalizations of heart transplant recipients between 1999 and 2014 in the United States and among these 1,953 patients (6.5%) suffered SCA with an increasing trend of admissions for SCA. Among the patients who suffered from SCA, 18.83% died during the same hospitalization, 19.29% were discharged to a long-term facility, and 61.38% were discharged home. Multivariate analysis demonstrated that conduction system disorders (Hazard ratio [95% confidence interval]; 7.1 [4.5-11.1]), female gender (HR:1.2 [1.1-1.3]), diabetes (HR:1.4 [1.2-1.6]), and hypertension (HR:1.2 [1.1-1.4]) were the strongest predictors for SCA. SCA hospitalizations occur in 6.5% of patients post cardiac transplant and have been increasing from 1999 to 2014. Conduction block, graft rejection, female gender, hypertension, diabetes are independent predictors for SCA in heart transplant recipients.

Cybersecurity: The need for data and patient safety with cardiac implantable electronic devices.

Remote monitoring of cardiac implantable electronic devices (CIEDs) has become routine practice as a result of the advances in biomedical engineering, the advent of interconnectivity between the devices through the Internet, and the demonstrated improvement in patient outcomes, survival, and hospitalizations. However, this increased dependency on the Internet of Things comes with risks in the form of cybersecurity lapses and possible attacks. Although no cyberattack leading to patient harm has been reported to date, the threat is real and has been demonstrated in research laboratory scenarios and echoed in patient concerns. The CIED universe comprises a complex interplay of devices, connectivity protocols, and sensitive information flow between the devices and the central cloud server. Various manufacturers use proprietary software and black-box connectivity protocols that are susceptible to hacking. Here we discuss the fundamentals of the CIED ecosystem, the potential security vulnerabilities, a historical overview of such vulnerabilities reported in the literature, and recommendations for improving the security of the CIED ecosystem and patient safety.

Shortness of breath and palpitations in an elderly man: Bad device behavior or malfunction?

70-year-old male with sinus node dysfunction (SND) and paroxysmal atrial fibrillation presents with shortness of breath and palpitations. Presenting EKG shows AF with rapid ventricular rates requiring direct current cardioversion (DCCV). Post-DCCV EKG shows sinus rhythm with competing ventricular pacing. Device interrogation demonstrates the patient's generator at the elective replacement indicator (ERI) and has been forced to VVI 65 bpm causing dyssynchronous ventricular pacing and inducing AF. This case highlights the importance of close device follow up with timely PPM generator change prior to ERI, especially in patients with Medtronic Adapta devices, to avoid unnecessary dyssynchronous ventricular pacing. In addition, device manufacturers should focus on maintaining AV synchrony in pacemakers when they reach ERI.

Incessant palpitations in a young male.

27-year-old male with incessant palpitations and reduced ejection fraction presents for diagnostic electrophysiology study. ECG shows a long RP tachycardia. Permanent junctional reciprocating tachycardia is diagnosed on EP study with successful ablation of posteroseptal accessory pathway.

Trends, burden, and impact of arrhythmia on cardiac amyloid patients: A 16-year nationwide study from 1999 to 2014.

BACKGROUND: Patients with cardiac amyloidosis (CA) have increased mortality, which can be explained in part by an increased risk of arrhythmias. The burden of arrhythmias in CA, their predictors, and impact on in-hospital outcomes remains unclear. The role of implantable cardioverter-defibrillators (ICD) in this population is also uncertain. METHODS: We queried the National Inpatient Sample (NIS) using ICD-9-CM codes 277.39 and 425.7 to identify CA. Twelve common arrhythmias were extracted using appropriate, validated ICD-9-CM codes. ICD implantation was identified using procedure ICD-9 codes 37.94 to 37.98, 00.51 and 00.54. RESULTS: There were a total of 145,920 CA hospitalizations between 1999 and 2014 in the United States and 56,199 (38.5%) of them were associated with arrhythmias. The prevalence of arrhythmias remained relatively constant from 41.5% in 1999 to 40.2% in 2014. The most common arrhythmia was atrial fibrillation (25.4%). In-patient mortality was significantly higher in CA patients with arrhythmias (10.4% vs 6.5%, P < .001). ICD implantation was performed in 1,381 (0.94%) patients with CA and analysis revealed an incremental trend in implantation over the study period (0.48% in 1999 to 0.65% in 2014). In-hospital mortality was significantly lower in patients who underwent ICD implantation (3.7% vs 8%; P = .0078). CA patients with arrhythmias also had an increased cost of hospitalization and length of stay ($65,046 ± 1,079 vs $53,322 ± 687 and 8.3 ± 0.1 vs 7.4 ± 0.1 days, respectively; P < .0001). CONCLUSION: Cardiac arrhythmias are common in patients with CA and are associated with worse in-hospital outcomes, increased length of stay, and cost of hospitalization.

In memory of tachycardia: A wide complex tachycardia in a young male.

We present a case of a 24-year-old male with palpitations and a wide complex tachycardia. Baseline electrocardiogram (ECG) after termination of tachycardia demonstrates a normal rhythm but with inferior/anterolateral T-wave inversions (TWIs). Electrophysiologic study confirmed the diagnosis of posterior fascicular ventricular tachycardia successfully terminated by anatomic ablation of the left posterior fascicle. TWIs on the patient's baseline ECG were consistent with cardiac memory.

Surgical and endoscopic management of a pericardioesophageal fistula after radiofrequency pulmonary vein isolation.

INTRODUCTION: The most feared complication of pulmonary vein isolation (PVI) is an atrioesophageal fistula (AEF). While rare (0.1-0.25%), primary surgical closure (as opposed to esophageal stenting) is associated with lower mortality. Pericardioesophageal fistula (PEF) may present prior to fistulization into the atrium. Unfortunately, data on the optimal management of PEFs are lacking. CASE REPORT: Seventy-one-year-old male with AF presented with chest pain 3 weeks after radiofrequency PVI. Computed tomography angiography (CTA) chest and echocardiogram showed pneumopericardium. Barium esophagram showed extravasation from esophagus into the pericardium without connection to the left atrium. Sternotomy with mediastinal exploration exposed the pericardial defect, over which a CorMatrix patch was placed. The fistula was then stented endoscopically with endosuture fixation. Poststent esophagram did not show barium leak, and the patient was discharged home. One week later, the patient returned with enterococcal and candida bacteremia and an acute right parietal/occipital lobe infarct. Barium esophagram showed contrast extravasation into the pericardium. The patient rapidly succumbed to his illness and died. Autopsy revealed pericardial abscess posterior to the LA in communication with the esophagus. Extension to the LA was not seen. CONCLUSION: While the surgical treatment of AEF is relatively well established, there is no consensus in the management of PEF. While prior small series have suggested PEF may be managed with esophageal stenting, our case illustrates the limitations of this approach.

Left Pericardiophrenic Vein Pacing for Tachy-Brady Syndrome Due to an Obstructing Cardiac Angiosarcoma.

We describe a case of a permanent pacemaker lead placement via the left pericardiophrenic vein for the treatment of tachy-brady syndrome due to a primary cardiac angiosarcoma. (Level of Difficulty: Advanced.).

Irrigated vs. Non-irrigated Catheters in the Ablation of Accessory Pathways.

There is a paucity of data comparing irrigated to non-irrigated catheters in the ablation of accessory pathways (AP) in adult patients. Retrospective analysis of first-time AP ablations performed at our institution from May 2010 to June 2017. A total of 69 AP ablations were studied; irrigated catheters were used in 78.3% cases. Mean age was 40.9 ± 14.3 years and 56.7% were male. Among APs, 63.8% were left sided and 56.5% were concealed. The total procedure time was 232.0 ± 89.0 min, ablation time was 3.1 ± 5.1 min, and fluoroscopy time was 13.9 ± 15.4 min. The overall acute success rate of ablation was 62/69 (89%). Success rates trended higher with irrigated catheters in both groups and were significant for the population as a whole (94.4% vs. 73.3%, p = 0.04). Analyzing the entire cohort, success rates were significantly higher in ablations using irrigated catheters.