Can adverse cardiac events of the COVID-19 vaccine exacerbate preexisting diseases?

INTRODUCTION: SARS-CoV-2 infection and COVID-19 vaccination can both lead to serious cardiac conditions such as myocarditis, arrhythmia, acute myocardial infarction, and coagulopathy. Further studies are needed to better understand the risks and benefits of COVID-19 vaccination, and to determine the best course of action for individuals with preexisting heart conditions. AREAS COVERED: The current knowledge and challenges in understanding vaccine-associated heart issues concerning the COVID-19 pandemic are briefly summarized, highlighting similar cardiac conditions caused by either SARS-CoV-2 infection or COVID-19 vaccination and the potential clinical impacts. EXPERT OPINION: The short-term risks of severe cardiovascular side effects following COVID-19 vaccination are relatively low. However, further studies are needed to determine whether adverse vaccination events outweigh the long-term benefits in specific groups of individuals. Since cardiac inflammation, blood pressure dysregulation, coagulopathy, acute myocardial infarction, or arrhythmia could be the consequences of either SARS-CoV-2 infection or COVID-19 vaccination, clinical questions should be asked whether the COVID-19 vaccine worsens the condition in persons with preexisting heart diseases. It is important to carefully assess the potential risks and benefits of COVID-19 vaccination, especially for individuals with preexisting heart conditions, and to continue monitoring and studying the long-term effects of vaccination on cardiovascular health.

Incidence, risk assessment and prevention of sudden cardiac death in cardiomyopathies.

Cardiomyopathies are a significant contributor to cardiovascular morbidity and mortality, mainly due to the development of heart failure and increased risk of sudden cardiac death (SCD). Despite improvement in survival with contemporary treatment, SCD remains an important cause of mortality in cardiomyopathies. It occurs at a rate ranging between 0.15% and 0.7% per year (depending on the cardiomyopathy), which significantly surpasses SCD incidence in the age- and sex-matched general population. The risk of SCD is affected by multiple factors including the aetiology, genetic basis, age, sex, physical exertion, the extent of myocardial disease severity, conduction system abnormalities, and electrical instability, as measured by various metrics. Over the past decades, the knowledge on the mechanisms and risk factors for SCD has substantially improved, allowing for a better-informed risk stratification. However, unresolved issues still challenge the guidance of SCD prevention in patients with cardiomyopathies. In this review, we aim to provide an in-depth discussion of the contemporary concepts pertinent to understanding the burden, risk assessment and prevention of SCD in cardiomyopathies (dilated, non-dilated left ventricular, hypertrophic, arrhythmogenic right ventricular, and restrictive). The review first focuses on SCD incidence in cardiomyopathies and then summarizes established and emerging risk factors for life-threatening arrhythmias/SCD. Finally, it discusses validated approaches to the risk assessment and evidence-based measures for SCD prevention in cardiomyopathies, pointing to the gaps in evidence and areas of uncertainties that merit future clarification.

Incidence, management, and prognostic impact of arrhythmias in patients with Takotsubo syndrome: a nationwide retrospective cohort study.

AIMS: Arrhythmia is a major complication of Takotsubo syndrome (TTS). However, its incidence, management, and prognostic impact remain to be elucidated in a large cohort. METHODS AND RESULTS: We retrospectively identified 16 713 patients hospitalized for TTS between July 2010 and March 2021 from the Japanese Diagnosis Procedure Combination database. Serious arrhythmias were defined as ventricular tachycardia/fibrillation (VT/VF), 2nd-/3rd-degree atrioventricular block (AVB), sick sinus syndrome (SSS), or unspecified arrhythmias requiring device treatment. Patient characteristics and outcomes were compared based on the occurrence of serious arrhythmias. The overall incidence proportion of serious arrhythmias was 6.2% (n = 1036; 449 VT/VF, 283 2nd-/3rd-degree AVB, 133 SSS, 55 multiple arrhythmias, 116 others), which remained stable over 11 years. The arrhythmia group was younger, more often male, and exhibited greater impairment in activities of daily living (ADLs) and consciousness than the non-arrhythmia group. Although crude in-hospital mortality was higher in the arrhythmia group (9.6% vs. 5.0%, P < 0.001), the significant association between arrhythmias and mortality disappeared after adjustment for confounders (odds ratio = 1.15, 95% confidence interval = 0.90-1.49). Meanwhile, age, sex, ADLs, consciousness level, and Charlson comorbidity index were significantly associated with mortality. In the arrhythmia group, 254 (24.5%) patients received pacemakers (18.4%) or defibrillators (6.1%), which were implanted at a median of 8 and 19 days after admission, respectively. CONCLUSION: Arrhythmias are not uncommon in TTS. Patients' background characteristics, rather than arrhythmia itself, may be associated with in-hospital mortality. Given the reversibility of cardiac dysfunction in TTS, there may be unnecessary device implantations for arrhythmias occurring as sequelae to TTS, warranting further investigations.

Italian return to play protocol after COVID-19 in young competitive and professional athletes: diagnostic yield and cost-benefit analysis.

BACKGROUND: Return to play (RTP) protocols have been proposed to early detect cardiovascular involvement due to COVID-19 and reduce the risk of sports-related sudden cardiac death. However, uncertainties remain about the true prevalence of COVID-19 myopericarditis, the arrhythmic risk and the cost of this protocol. METHODS: We collected data from 217 competitive and professional athletes of both genders who underwent RTP protocol (clinical history, resting and exercise ECG, and echocardiography). Holter monitoring and/or cardiac magnetic resonance (CMR) were performed in case of abnormalities. In 107 athletes, the RTP data were compared with those of preparticipation evaluation (PPE) performed prior to COVID-19 infection. RESULTS: Out of 217 consecutive athletes evaluated with the RTP protocol, 7 underwent CMR: among these we found alterations compatible with myopericarditis in 3 (1.4%), with a cost per person of € 223.93 and a cost per diagnosis of € 16,197.53. Of the 107 athletes previously evaluated with PPE, 4 underwent RMC: we made a final diagnosis of myocarditis in 1 athlete (0.9%), whereas another athlete (0.9%) showed moderate pericardial effusion. The clinical presentation of both these athletes was characterized by the presence of ventricular arrhythmias newly detected during RTP. Compared to PPE, during RTP higher values were observed for shortness of breath, weight, heart rate and corrected QT interval, whereas lower values for sinus bradycardia and the E/A ratio of mitral flow. CONCLUSIONS: The prevalence of myopericarditis was similar to that reported in previous cross-sectional and case-control studies. The availability of data recorded before COVID-19 was important in the evaluation of athletes with arrhythmias. The RTP protocol has proven to be less cost effective than normal PPE.

Assessment of Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios in patients with acromegaly.

BACKGROUND: Cardiovascular complications, including ventricular arrhythmias associated with abnormalities of ventricular repolarization, are the leading cause of morbidity and mortality in patients with acromegaly. Herein, we aimed to investigate ventricular repolarization using Tp-e interval, Tp-e interval/QT, and Tp-e interval/QTc ratios in acromegalic patients compared to healthy subjects. METHODS: A total of 29 patients (aged 51.9 ± 11.2, 65.5% women) with acromegaly and 30 control subjects (aged 47.3 ± 14.4, 63.3% women) were enrolled in the study. Tp-e and QT interval, corrected QT (QTc), Tp-e/QT, and Tp-e/QTc ratios were calculated from the 12-lead electrocardiogram. RESULTS: Tp-e interval (89.28 ± 12.16 vs. 75.97 ± 9.92 ms; p < 0.001), Tp-e/QT ratio (0.237 ± 0.045 vs. 0.212 ± 0.029; p = 0.019), and Tp-e/ QTc ratio (0.218 ± 0.031 vs. 0.195 ± 0.026; p = 0.003) were significantly higher in patients with acromegaly compared to control group. A positive correlation was determined between left atrial volume index (LAVI) and Tp-e interval (r = 0.272, p = 0.039). DISCUSSION: The current study is the first to have shown significantly increased Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were increased in acromegalic patients. These results may be important for screening malignant arrhythmic events in acromegaly.

Impact of Device Miniaturization on Insertable Cardiac Monitor Use in the Pediatric Population: An Analysis of the MarketScan Commercial and Medicaid Databases.

Background Insertable cardiac monitors (ICMs) are effective in the detection of paroxysmal arrhythmias. In 2014, the first miniaturized ICM was introduced with a less invasive implant technique. The impact of this technology on ICM use in pediatric patients has not been evaluated. We hypothesized an increase in annual pediatric ICM implants starting in 2014 attributable to device miniaturization. Methods and Results A retrospective observational study was conducted using administrative claims from MarketScan Medicaid and commercial insurance claims databases. Use of ICM between January 2013 and December 2018 was measured (normalized to the total enrolled population ≤18 years) and compared with balancing measures (Holter ambulatory monitors, cardiac event monitors, encounters with syncope diagnosis, implantation of implantable cardioverter-defibrillator/pacemaker). Secondary analyses included evaluations of subsequent interventions and complications. The study cohort included 33 532 185 individual subjects, of which 769 (0.002%) underwent ICM implantation. Subjects who underwent ICM implantation were 52% male sex, with a median age of 16 years (interquartile range, 10-17 years). A history of syncope was present in 71%, palpitations in 43%, and congenital heart disease in 28%. Following release of the miniaturized ICM, use of ICMs increased from 5 procedures per million enrollees in 2013 to 11 per million between 2015 and 2018 (P<0.001), while balancing measures remained static. Of 394 subjects with ≥1 year of follow-up after implantation, interventions included catheter ablation in 24 (6%), pacemaker implantation in 15 (4%), and implantable cardioverter-defibrillator implantation in 7 (2%). Conclusions Introduction of the miniaturized ICM was followed by a rapid increase in pediatric use. The effects on outcomes and value deserve further attention.

Arrhythmias in Female Patients: Incidence, Presentation and Management.

There is a growing appreciation for differences in epidemiology, treatment, and outcomes of cardiovascular conditions by sex. Historically, cardiovascular clinical trials have under-represented females, but findings have nonetheless been applied to clinical care in a sex-agnostic manner. Thus, much of the collective knowledge about sex-specific cardiovascular outcomes result from post hoc and secondary analyses. In some cases, these investigations have revealed important sex-based differences with implications for optimizing care for female patients with arrhythmias. This review explores the available evidence related to cardiac arrhythmia care among females, with emphasis on areas in which important sex differences are known or suggested. Considerations related to improving female enrollment in clinical trials as a way to establish more robust clinical evidence for the treatment of females are discussed. Areas of remaining evidence gaps are provided, and recommendations for areas of future research and specific action items are suggested. The overarching goal is to improve appreciation for sex-based differences in cardiac arrhythmia care as 1 component of a comprehensive plan to optimize arrhythmia care for all patients.

Prevalence, Outcomes, and Management of Ventricular Arrhythmias in COVID-19 Patients.

We review the current data on epidemiology, the clinical significance, the pathophysiologic mechanisms, and the treatment of VAs in the setting of COVID-19. VAs prevail in 0.15% to 8% of hospitalized patients, but only sustained and rapid tachyarrhythmias are purportedly associated with a significant increase in mortality. Multiple factors can elicit VAs, which are ultimately deemed to be a marker of severe systemic disease rather than a distinct cardiac condition. Even though the electrophysiologist plays a determinant role in the secondary prevention of VAs, a multidisciplinary approach is indispensable for primary prophylaxis and acute management.

Long-term assessment of clinical outcomes and disease progression in patients with corrected Tetralogy of Fallot.

OBJECTIVE: Understanding changes of right ventricular (RV) geometry and function in repaired Tetralogy of Fallot (rToF) patients can improve decision-making for pulmonary valve replacement. Therefore, we aimed to assess the magnitude and clinical correlations of RV changes in rToF patients. PATIENTS AND METHODS: Clinical and MRI data of rToF patients who underwent repeated cardiac magnetic resonance imaging (MRI) at two centers between December 2003 and September 2020 were analyzed together with anatomical factors, including RV outflow tract obstruction, pulmonary artery branch stenosis, and tricuspid regurgitation. Adverse cardiac events and/or NYHA class worsening were documented and correlated with MRI changes. QRS length was reported at each MRI. RESULTS: Two-hundred-and-nineteen rToF patients (53% males, aged 20.2 ± 10.1 years) were enrolled. An increase of ventricular dimensions, except LVEDVi, and worsening of right and left ejection fractions were found over an average period of 5 years of follow-up. These changes were statistically significant but within 10% of the initial value. No significant changes were reported on a year-to-year basis, except in a small group of patients (6%) in whom no predictive factors were identified. Despite similar RV dimensions at the first examination, younger patients had a higher RV ejection fraction and a different annual rate of change of ventricular dimensions compared to older ones. Patients with arrhythmias (20%) were more frequently older and had larger RV dimensions but showed no significant correlations with MRI changes/years. CONCLUSIONS:  Changes in RV dimensions and function occur rarely and very slowly in rToF patients. A small percentage of patients experience a significant worsening in a short time interval without any recognized risk factors. Arrhythmias appear to occur in a small percentage of cases in the late follow-up.

Epidemiology, evaluation, and management of conduction disturbances after transcatheter aortic valve replacement.

Aortic stenosis is the most common valvulopathy requiring replacement by means of the surgical or transcatheter approach. Transcatheter aortic valve replacement (TAVR) has quickly become a viable and often preferred treatment strategy compared to surgical aortic valve replacement. However, transcatheter heart valve system deployment not infrequently injures the specialized electrical system of the heart, leading to new conduction disorders including high-grade atrioventricular block and complete heart block (CHB) necessitating permanent pacemaker implantation (PPI), which may lead to deleterious effects on cardiac function and patient outcomes. Additional conduction disturbances (e.g., new-onset persistent left bundle branch block, PR/QRS prolongation, and transient CHB) currently lack clearly defined management algorithms leading to variable strategies among institutions. This article outlines the current understanding of the pathophysiology, patient and procedural risk factors, means for further risk stratification and monitoring of patients without a clear indication for PPI, our institutional approach, and future directions in the management and evaluation of post-TAVR conduction disturbances.

Arrhythmia Risk During the 2016 US Presidential Election: The Cost of Stressful Politics.

Background Anger and extreme stress can trigger potentially fatal cardiovascular events in susceptible people. Political elections, such as the 2016 US presidential election, are significant stressors. Whether they can trigger cardiac arrhythmias is unknown. Methods and Results In this retrospective case-crossover study, we linked cardiac device data, electronic health records, and historic voter registration records from 2436 patients with implanted cardiac devices. The incidence of arrhythmias during the election was compared with a control period with Poisson regression. We also tested for effect modification by demographics, comorbidities, political affiliation, and whether an individual's political affiliation was concordant with county-level election results. Overall, 2592 arrhythmic events occurred in 655 patients during the hazard period compared with 1533 events in 472 patients during the control period. There was a significant increase in the incidence of composite outcomes for any arrhythmia (incidence rate ratio [IRR], 1.77 [95% CI, 1.42-2.21]), supraventricular arrhythmia (IRR, 1.82 [95% CI, 1.36-2.43]), and ventricular arrhythmia (IRR, 1.60 [95% CI, 1.22-2.10]) during the election relative to the control period. There was also an increase in specific types of arrhythmia, including atrial fibrillation (IRR, 1.50 [95% CI, 1.06-2.11]), supraventricular tachycardia (IRR, 3.7 [95% CI, 2.2-6.2]), nonsustained ventricular tachycardia (IRR, 1.7 [95% CI, 1.3-2.2]), and daily atrial fibrillation burden (P<0.001). No significant interaction was found for sex, race/ethnicity, device type, age ≥65 years, hypertension, coronary artery disease, heart failure, political affiliation, or concordance between individual political affiliation and county-level election results. Conclusions There was a significant increase in cardiac arrhythmias during the 2016 US presidential election. These findings suggest that exposure to stressful sociopolitical events may trigger arrhythmogenesis in susceptible people.

Transcatheter Versus Surgical Aortic Valve Replacement in the United States (From the Nationwide Readmission Database).

Clinical outcomes of transcatheter aortic valve implantation (TAVI) have significantly improved with the accumulation of operator and institution experience as well as the wide use of newer generation devices. There is limited data on TAVI outcomes compared with surgical aortic valve replacement (SAVR) in contemporary practice in the United States. We queried the 2018 Nationwide Readmission Database of the United States. International Classification Diagnosis code 10 was used to extract TAVI and SAVR admissions. A propensity-matched cohort was created to compare TAVI and SAVR outcomes. A weighted 48,349 TAVI and 24,896 SAVR for aortic stenosis were included and 4.9% of TAVI were performed with an embolic protection device. In propensity-matched cohort (12,708 TAVI and 12,708 SAVR), TAVI conferred lower in-hospital mortality (1.7% vs 3.8%), acute kidney injury (11.3% vs 22.9%), and transfusion rate (5.9% vs. 20.6%) whereas new pacemaker rate was higher in TAVI compared with SAVR (10.5% vs. 7.0%) (all p values < 0.001). Stroke rate was similar between TAVI and SAVR (1.5% vs. 1.5%) (p value = 0.79). The routine discharge was more frequent (66.9% vs 25.8%) and length of stay was shorter (4.8 vs. 9.8 days) in TAVI than SAVR. Hospitalization cost was higher in SAVR than TAVI (51,962 vs 57,754 U.S. dollars) (all p values < 0.001). In-hospital mortality was also lower in TAVI compared with isolated SAVR. TAVI was performed more frequently than SAVR in 2018 in the United States with lower in-hospital mortality of TAVI compared with both SAVR and isolated SAVR.

The Assessment of Ventricular Arrhythmia Indicators Based on Electrocardiography in Patients With Differentiated Thyroid Cancer Followed Up With Levothyroxine Suppression.

Levothyroxine suppression therapy (LST) can cause some unfavorable effects on the cardiovascular system in patients with differentiated thyroid cancer (DTC). The aim of this study was to evaluate ventricular arrhythmia predictors based on electrocardiography (ECG) in patients with DTC with LST. The ECG parameters including QT, corrected QT (QTc), Tp-e intervals, Tp-e/QT, and Tp-e/QTC ratios of 265 patients with DTC who met the inclusion criteria were compared with 100 controls. No difference was observed in the number of patients with DTC and controls with prolonged and borderline QTc interval (P = .273). Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were significantly higher in patients (P = .002, P = .02, P = .003; respectively). Linear regression analysis suggested that male gender was a predictor of higher Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios (ß = 4.322, R2 = 0.024, P = .042; ß = 0.016, R2 = 0.048, P = .005; ß = 0.015, R2 = 0.044, P = .006, respectively). A higher serum fT4 level was found to be associated with a higher Tp-e/QT ratio (ß = 0.018, R2 = 0.089, P = .007). Ventricular arrhythmia indicators were found to be higher in patients with DTC with LST. Defining ventricular arrhythmia predictors through ECG, an easily accessible cardiac diagnostic tool, can be potentially useful in raising awareness of the possible cardiac harm of LST.

Human Health Risks of Conducted Electrical Weapon Exposure: A Systematic Review.

Importance: Conducted electrical weapons (CEWs) are used broadly as a less-lethal force option for police officers. However, there is no clear picture of the possible health risks in humans on the basis of rigorously assessed scientific evidence from the international peer-reviewed literature. Objective: To synthesize and systematically evaluate the strength of published evidence for an association between exposure to different models of CEWs and adverse acute as well as chronic conditions. Evidence Review: Following a preregistered review protocol, the literature search strategy was based on a search of reviews published between January 1, 2000, and April 24, 2020, of PubMed, MEDLINE, EMBASE, Web of Science, PsycINFO, and Cochrane Library, as well as relevant online databases and bibliographic sources, such as reference sections of recent publications. The identified studies were independently assessed in terms of scope, relevance, methodologic bias, and quality. Peer-reviewed publications of human studies were included, using original data and with a focus on the use of taser CEWs in the context of law enforcement. Eligible studies examined clearly defined health outcomes as dependent variables following exposure to a CEW. The review followed the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. A meta-analysis could not be conducted. Findings: Of the 1081 unique records screened, 33 relevant studies were identified, all of them of experimental design and conducted in the US. Eleven studies had a low risk of bias and 22 had a higher bias risk. Studies focused on outcomes such as physiologic stress responses, heart rate, blood pressure, arrhythmias, or cognitive performance. Independently of bias risk, the studies reported few or no acute health problems, apart from the wounds caused by the darts. Furthermore, no long-term outcomes were studied. Most of the studies were performed on healthy, physically fit individuals (eg, police officers) in a controlled setting, with short exposure duration (5 seconds). Half of the studies, mainly those with a higher risk of bias, were at least partly funded by the manufacturer. Conclusions and Relevance: Based on the findings of the reviewed studies, the risk for adverse health outcomes due to CEW exposure can be currently estimated as low. However, most of the reviewed studies had methodologic limitations. Considering that recruited participants were not representative of the population that usually encounters a CEW deployment, it is not possible to draw conclusions regarding exposure outcomes in potentially vulnerable populations or high-risk groups, such as those under the influence of substances.

Resource Use and Economic Implications of Remote Monitoring With Subcutaneous Cardiac Rhythm Monitors.

OBJECTIVES: This study reports resource use and economic implications of rhythm monitoring with subcutaneous cardiac rhythm monitors (SCRMs). BACKGROUND: SCRMs generate a substantial amount of data that requires timely adjudication for appropriate clinical care. Resource use for SCRM monitoring is not known. METHODS: The study included consecutive transmissions during 4 weeks from 1,811 SCRMs. Resource use was quantified by assessment of time commitment of device clinic personnel and electrophysiologists for data adjudication. Incidence and characteristics of false positive (FP) episodes were assessed. Impact of custom programming for arrhythmia detection on incidence of FP episodes and resource use was analyzed. RESULTS: A total of 1,457 transmissions (alerts = 462; full downloads = 995) were received during study period. Average device clinic personnel time for adjudication of 1 transmission was 15 ± 6 min. This totaled to 364 h spent (2.3 full-time staff) over the 4-week period, which translated into a salary cost of $12,000 U.S. dollars (USD). Average time spent by an electrophysiologist for 1 transmission was 1.5 ± 1 min and totaled to 37 h for 4 weeks, which translated into an estimated cost of $9,600 USD. Of 1,457 total transmissions, 512 (35%) represented multiple transmissions from the same patients, which resulted in no additional reimbursement. Incidence of FP episodes in the entire cohort was 50% and was variable in alert (60%) and full download (49%) (p = 0.04) transmissions. When SCRMs with manufacturer suggested nominal programming and institutional custom programming were compared, there was a reduction in FP episodes (55% vs. 16%; p = 0.01), which translated to a 34% reduction in resource use for data adjudication. CONCLUSIONS: SCRM data adjudication requires significant resources. Custom programming for SCRMs may overcome the data deluge.

Ventricular arrhythmia burden during the coronavirus disease 2019 (COVID-19) pandemic.

AIMS: Our objective was to determine the ventricular arrhythmia burden in implantable cardioverter-defibrillator (ICD) patients during COVID-19. METHODS AND RESULTS: In this multicentre, observational, cohort study over a 100-day period during the COVID-19 pandemic in the USA, we assessed ventricular arrhythmias in ICD patients from 20 centres in 13 states, via remote monitoring. Comparison was via a 100-day control period (late 2019) and seasonal control period (early 2019). The primary outcome was the impact of COVID-19 on ventricular arrhythmia burden. The secondary outcome was correlation with COVID-19 incidence. During the COVID-19 period, 5963 ICD patients underwent remote monitoring, with 16 942 episodes of treated ventricular arrhythmias (2.8 events per 100 patient-days). Ventricular arrhythmia burden progressively declined during COVID-19 (P < 0.001). The proportion of patients with ventricular arrhythmias amongst the high COVID-19 incidence states was significantly reduced compared with those in low incidence states [odds ratio 0.61, 95% confidence interval (CI) 0.54-0.69, P < 0.001]. Comparing patients remotely monitored during both COVID-19 and control periods (n = 2458), significantly fewer ventricular arrhythmias occurred during COVID-19 [incident rate ratio (IRR) 0.68, 95% CI 0.58-0.79, P < 0.001]. This difference persisted when comparing the 1719 patients monitored during both the COVID-19 and seasonal control periods (IRR 0.69, 95% CI 0.56-0.85, P < 0.001). CONCLUSIONS: During COVID-19, there was a 32% reduction in ventricular arrhythmias needing device therapies, coinciding with measures of social isolation. There was a 39% reduction in the proportion of patients with ventricular arrhythmias in states with higher COVID-19 incidence. These findings highlight the potential role of real-life stressors in ventricular arrhythmia burden in individuals with ICDs. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry; URL: https://www.anzctr.org.au/; Unique Identifier: ACTRN12620000641998.

Impact of Arrhythmias on Hospitalizations in Patients With Cardiac Amyloidosis.

Cardiac involvement in amyloidosis is associated with a poor prognosis. Data on the burden of arrhythmias in patients with cardiac amyloidosis (CA) during hospitalization are lacking. We identified the burden of arrhythmias using the National Inpatient Sample (NIS) database from January 2016 to December 2017. We compared patient characteristics, outcomes, and hospitalization costs between CA patients with and without documented arrhythmias. Out of 5,585 hospital admissions for CA, 2,020 (36.1%) had concurrent arrhythmias. Propensity-score matching for age, sex, income, and co-morbidities was performed with 1,405 CA patients with arrhythmias and 1,405 patients without. The primary outcome of all-cause mortality was significantly higher in CA patients with arrhythmia than without(13.9% vs 5.3%, p-value <0.001). Atrial fibrillation (AF) was the most common (72.2%) arrhythmia in CA patients with concurrent arrhythmia. The secondary outcomes of AF-related mortality (11.95% vs 9.16%, p-value = 0.02) and acute and acute on chronic as heart failure (HF) exacerbation (32.38% vs 24.91%, p-value <0.0001) were significantly higher in CA and concurrent arrhythmia compared with CA patients without. The total length of hospital stay (6[3 to 12] vs 5[3 to 10], p-value <0.001) and cost of hospitalization were ($ 15,086[7,813 to 30,373] vs $ 12,219[6,865 to 23,997], p-value = 0.001) were significantly greater among CA with arrhythmia compared with those without. These data suggest that the presence of arrhythmias in CA patients during hospital admission is associated with a poorer prognosis and may reflect patients with a higher risk of HF exacerbation and mortality.