The clinical and economic impact of extended battery longevity of a substernal extravascular implantable cardioverter defibrillator.

INTRODUCTION: The extravascular implantable cardioverter defibrillator (EV ICD) has extended projected battery longevity compared to the subcutaneous implantable cardioverter defibrillator (S-ICD). This study used modeling to characterize the need for generator changes, long-term complications, and overall costs for both the EV ICD and S-ICD in healthcare systems of various countries. METHODS: Battery longevity data were modeled using a Markov model from averages reported in device labeling for the S-ICD and with engineering estimates based on real life usage from EV ICD Pivotal Study patient data to introduce variability. Clinical demographic data were derived from published literature. The primary outcomes were defined as the number of generator replacement surgeries, complications, and total healthcare system costs due to battery depletion over the expected lifetime of patients receiving EV ICD or S-ICD therapy. RESULTS: Average modeled battery longevity was determined to be 7.3 years for the S-ICD versus 11.8 years for the EV ICD. The probability of a complication after a replacement procedure was 1.4%, with an operative mortality rate of 0.02%. The use of EV ICD was associated with 1.4-1.6 fewer replacements on average over an expected patient lifetime as compared to S-ICD and a 24.3%-26.0% reduction in cost. A one-way sensitivity analysis of the model for the US healthcare system found that use of an EV ICD resulted in a reduction in replacement surgeries of greater than 1 (1.1-1.6) along with five-figure cost savings in all scenarios ($18 602-$40 948). CONCLUSION: The longer projected battery life of the EV ICD has the potential to meaningfully reduce long-term morbidity and healthcare resources related to generator changes from the perspective of multiple diverse healthcare systems.

Epicardial ablation of ventricular tachycardia in ischemic cardiomyopathy: A review and local experience.

Myocardial scar in ischemic cardiomyopathy is predominantly endocardial, however, between 5% and 15% of these patients have an arrhythmogenic epicardial substrate. Percutaneous epicardial ablation should be considered in patients with ICM and VT especially if they failed an endocardial ablation. Simultaneous epicardial and endocardial ablation of VT in ICM may reduce short- and medium-term VT recurrence compared with an endocardial only approach. Cardiac imaging could be used to help guide patient selection for a combined epi-endo approach. Complications related to epicardial access can happen in up to 7% of patients. Epicardial ablation in these patients should be referred to experienced tertiary centers. We review the literature and share interesting cases.

A Data-Driven Preprocessing Framework for Atrial Fibrillation Intracardiac Electrocardiogram Analysis.

Atrial Fibrillation (AF) is the most common cardiac arrhythmia. Signal-processing approaches are widely used for the analysis of intracardiac electrograms (iEGMs), which are collected during catheter ablation from patients with AF. In order to identify possible targets for ablation therapy, dominant frequency (DF) is widely used and incorporated in electroanatomical mapping systems. Recently, a more robust measure, multiscale frequency (MSF), for iEGM data analysis was adopted and validated. However, before completing any iEGM analysis, a suitable bandpass (BP) filter must be applied to remove noise. Currently, no clear guidelines for BP filter characteristics exist. The lower bound of the BP filter is usually set to 3-5 Hz, while the upper bound (BP¯th) of the BP filter varies from 15 Hz to 50 Hz according to many researchers. This large range of BP¯th subsequently affects the efficiency of further analysis. In this paper, we aimed to develop a data-driven preprocessing framework for iEGM analysis, and validate it based on DF and MSF techniques. To achieve this goal, we optimized the BP¯th using a data-driven approach (DBSCAN clustering) and demonstrated the effects of different BP¯th on subsequent DF and MSF analysis of clinically recorded iEGMs from patients with AF. Our results demonstrated that our preprocessing framework with BP¯th = 15 Hz has the best performance in terms of the highest Dunn index. We further demonstrated that the removal of noisy and contact-loss leads is necessary for performing correct data iEGMs data analysis.

Premature Ventricular Complexes: Benign versus Malignant - How to approach?

Premature Ventricular Complexes (PVCs) refer to electrical activity arising from ventricles resulting in ventricular contraction independent of the native rhythm. PVCs by themselves are common in the general population but based on the origin of the PVCs, either related to anatomical or electrical substrate, the disease process has a widely varied presentation and prognosis. The clinical presentation of symptoms may vary from being extremely benign, or very severe (malignant). Benign PVCs include those that are asymptomatic or induce very mild symptoms including palpitations, lightheadedness, chest discomfort, or the sensation of skipped beats. The middle range of PVCs present as heart failure or heart failure complicated by PVCs. The malignant variety may present as syncope, or sudden cardiac death. In this review we describe the multiple facets of PVC presentation and strategies of clinical management.

Novel mapping techniques for rotor core detection using simulated intracardiac electrograms.

BACKGROUND: Catheter ablation is associated with limited success rates in patients with persistent atrial fibrillation (AF). Currently, existing mapping systems fail to identify critical target sites for ablation. Recently, we proposed and validated several techniques (multiscale frequency [MSF], Shannon entropy [SE], kurtosis [Kt], and multiscale entropy [MSE]) to identify pivot point of rotors using ex-vivo optical mapping animal experiments. However, the performance of these techniques is unclear for the clinically recorded intracardiac electrograms (EGMs), due to the different nature of the signals. OBJECTIVE: This study aims to evaluate the performance of MSF, MSE, SE, and Kt techniques to identify the pivot point of the rotor using unipolar and bipolar EGMs obtained from numerical simulations. METHODS: Stationary and meandering rotors were simulated in a 2D human atria. The performances of new approaches were quantified by comparing the "true" core of the rotor with the core identified by the techniques. Also, the performances of all techniques were evaluated in the presence of noise, scar, and for the case of the multielectrode multispline and grid catheters. RESULTS: Our results demonstrate that all the approaches are able to accurately identify the pivot point of both stationary and meandering rotors from both unipolar and bipolar EGMs. The presence of noise and scar tissue did not significantly affect the performance of the techniques. Finally, the core of the rotors was correctly identified for the case of multielectrode multispline and grid catheter simulations. CONCLUSION: The core of rotors can be successfully identified from EGMs using novel techniques; thus, providing motivation for future clinical implementations.

Device Therapy and Arrhythmia Management in Left Ventricular Assist Device Recipients: A Scientific Statement From the American Heart Association.

Left ventricular assist devices (LVADs) are an increasingly used strategy for the management of patients with advanced heart failure with reduced ejection fraction. Although these devices effectively improve survival, atrial and ventricular arrhythmias are common, predispose these patients to additional risk, and complicate patient management. However, there is no consensus on best practices for the medical management of these arrhythmias or on the optimal timing for procedural interventions in patients with refractory arrhythmias. Although the vast majority of these patients have preexisting cardiovascular implantable electronic devices or cardiac resynchronization therapy, given the natural history of heart failure, it is common practice to maintain cardiovascular implantable electronic device detection and therapies after LVAD implantation. Available data, however, are conflicting on the efficacy of and optimal device programming after LVAD implantation. Therefore, the primary objective of this scientific statement is to review the available evidence and to provide guidance on the management of atrial and ventricular arrhythmias in this unique patient population, as well as procedural interventions and cardiovascular implantable electronic device and cardiac resynchronization therapy programming strategies, on the basis of a comprehensive literature review by electrophysiologists, heart failure cardiologists, cardiac surgeons, and cardiovascular nurse specialists with expertise in managing these patients. The structure and design of commercially available LVADs are briefly reviewed, as well as clinical indications for device implantation. The relevant physiological effects of long-term exposure to continuous-flow circulatory support are highlighted, as well as the mechanisms and clinical significance of arrhythmias in the setting of LVAD support.

Thinking inside the box: Custom pacemaker improves device longevity in a congenital heart patient.

Patients with congenital heart disease have unique pacing challenges and often require epicardial systems. High pacing threshold is one of the major factors that decrease these systems' durability. Sometimes surgical reintervention or lead replacement is difficult or prohibitive in these patients due to repeated surgeries and extensive epicardial scar. We present a case report of a patient with Fontan physiology and chronically high epicardial lead pacing thresholds requiring frequent generator changes and a unique solution focusing on improving generator longevity.

Impact of the inflammation on the outcomes of catheter ablation of drug-refractory ventricular tachycardia in cardiac sarcoidosis.

INTRODUCTION: Catheter ablation (CA) of ventricular tachycardia (VT) in cardiac sarcoidosis (CS) has been reported with varying success. However, there is a scarcity of data on the outcomes of CA based on ongoing inflammation. OBJECTIVE: We hypothesized that the response to VT ablation depends upon the stage of the disease. METHODS: Between July 2004 and December 2018, 24 patients of CS presented with drug-refractory VT at CARE Hospital (Hyderabad) and the University of Minnesota (Minneapolis, MN). Patients were classified into two groups based on cardiac magnetic resonance imaging and positron emission tomography: (a) inflammatory phase, (b) scar phase. All patients underwent 3D electro-anatomic mapping guided CA. RESULTS: The clinical VT was ablated in all but one patient. In 16 patients (66.6%), both the clinical and nonclinical VTs were ablated (complete success), while in seven patients (29.1%) nonclinical VTs was still inducible. In patients with inflammation (group A), complete success for VT ablation was achieved in 10 out of 17 (58.8%). In patients without inflammation (group B), complete success was achieved in six out of seven patients (85.7%). Eleven patients (45.8%) had a recurrence of VT. Among patients in the inflammatory phase (group A): 10 out of 17 patients had a recurrence of VT, while only one out of seven patients in the scar phase (group B) had VT recurrence over a mean follow-up of 5.7 ± 3.9 years. Epicardial ablation was performed in 10 (41.6%) patients. CONCLUSION: CA of drug-refractory VT in CS is effective, often requiring the epicardial approach. Incomplete success and recurrence of VT were higher in the inflammatory phase of the disease.

Clinical characteristics and organ system involvement in sarcoidosis: comparison of the University of Minnesota Cohort with other cohorts.

BACKGROUND: Sarcoidosis is a systemic granulomatous disease of unknown etiology. Clinical cohort studies of different populations are important to understand the high variability in clinical presentation and disease course of sarcoidosis. The aim of the study is to evaluate clinical characteristics, including organ involvement, pulmonary function tests, and laboratory parameters, in a sarcoidosis cohort at the University of Minnesota. We compare the organ system involvement of this cohort with other available cohorts. METHODS: We conducted a retrospective data collection and analysis of 187 subjects with biopsy-proven sarcoidosis seen at a tertiary center. Organ system involvement was determined using the WASOG sarcoidosis organ assessment instrument. Clinical phenotype groups were classified using the Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis criteria. RESULTS: Mean subject age at diagnosis was 45.8 ± 12.4, with a higher proportion of males (55.1%), and a higher proportion of blacks (17.1%) compared to the racial distribution of Minnesota residents (5.95%). The majority (71.1%) of subjects required anti-inflammatory therapy for at least 1 month. Compared to the A Case Control Etiologic Study of Sarcoidosis cohort, there was a higher frequency of extra-thoracic lymph node (34.2% vs. 15.2%), eye (20.9% vs. 11.8%), liver (17.6% vs. 11.5%), spleen (20.9% vs. 6.7%), musculoskeletal (9.6% vs. 0.5%), and cardiac (10.7% vs. 2.3%) involvement in our cohort. A multisystem disease with at least five different organs involved was identified in 13.4% of subjects. A restrictive physiological pattern was observed in 21.6% of subjects, followed by an obstructive pattern in 17.3% and mixed obstructive and restrictive pattern in 2.2%. Almost half (49.2%) were Scadding stages II/III. Commonly employed disease activity markers, including soluble interleukin-2 receptor and angiotensin-converting enzyme, did not differ between treated and untreated groups. CONCLUSIONS: This cohort features a relatively high frequency of high-risk sarcoidosis phenotypes including cardiac and multiorgan disease. Commonly-utilized serum biomarkers do not identify subpopulations that require or do better with treatment. Findings from this study further highlight the high-variability nature of sarcoidosis and the need for a more reliable biomarker to predict and measure disease severity and outcomes for better clinical management of sarcoidosis patients.

Impact of QRS Duration and Ventricular Pacing on Clinical and Arrhythmic Outcomes in Continuous Flow Left Ventricular Assist Device Recipients: A Multicenter Study.

OBJECTIVES: Wide QRS duration and ventricular pacing are common in recipients of continuous-flow left ventricular assist devices (CF-LVADs) but their impact on outcomes remains unclear. We assessed the clinical and arrhythmic outcomes of CF-LVAD patients with wide QRS or right ventricular (RV) pacing at baseline, compared with those with narrow QRS and those with continued cardiac resynchronization therapy (CRT). METHODS AND RESULTS: A total of 520 patients (57 ± 13 years) with an implantable cardioverter-defibrillator (ICD) (n = 240) or CRT-defibrillator (n = 280) who underwent CF-LVAD implantation at 5 centers in 2007-2015 were studied. Patients were divided into 3 groups: ICD-N (QRS ≤120 ms; n = 134), ICD-W (QRS >120 ms; n = 106), and CRT (n = 280). Mortality, hospitalization, and ventricular arrhythmia (VA) incidence were compared among the groups. Baseline QRS duration was different among the groups (100 ± 13 [ICD-N] vs 155 ± 26 [ICD-W] vs 159 ± 29 ms [CRT]; P < .0001). In the ICD-W group, 37 (35%) had >80% RV pacing at baseline. Median biventricular pacing in the CRT group was 96%. Over 523 days of CF-LVAD support, Kaplan-Meier analysis showed no difference in survival among groups (log rank P = .9). According to multivariate Cox regression, wide QRS duration and RV pacing were not associated with survival. QRS narrowed during CF-LVAD support in the ICD-W and CRT groups but was not associated with improved survival (P = .9). No differences were noted among the groups in hospitalizations (P = .9), VA (P = .2), or ICD shocks (P = .06). CONCLUSIONS: In this large CF-LVAD cohort, a wide QRS duration, high percentage of RV pacing at baseline, and changes in QRS duration after LVAD implantation were not associated with survival. Continued CRT after CF-LVAD implantation also was not associated with improved survival or HF hospitalizations.

Mortality prediction using a modified Seattle Heart Failure Model may improve patient selection for ventricular tachycardia ablation.

BACKGROUND: Catheter ablation is frequently used as a palliative option to reduce shock burden in patients with ventricular tachycardia (VT). A risk prediction tool that accurately predicts short-term survival could improve patient selection for VT ablation. OBJECTIVE: The objective of the study is to assess utility of the Seattle Heart Failure Model (SHFM) to predict 6-month mortality in patients undergoing VT ablation. METHODS: Data on patients who underwent VT ablation at 2 tertiary institutions were retrospectively compiled. The SHFM score at the time of ablation, including 2 added VT variables, was used to predict 6-month mortality. The predicted number of deaths was compared to the observed number to assess model calibration. Model discrimination of those who died within 6 months was assessed by both K- and C-statistics. RESULTS: Mean age of the 243 patients was 63 ± 12 years; 89% were male. Mean SHFM score for the cohort was 1.3 ± 1.3. The Kaplan-Meier probability of death within 6 months was 14% (34 patients). The number of deaths estimated by the SHFM at 6 months was 31 (13%) giving a predicted to observed ratio of 0.91 (95% CI 0.64-1.30). The K-statistic for 6-month mortality predictions was 0.77 (95% CI 0.73-0.81), whereas the C-statistic was 0.84 (95% CI 0.78-0.92). Patients with an SHFM score ≥4.0 had an estimated positive predictive value of 80% (95% CI 28%-99%) for dying within 6 months of VT ablation. CONCLUSION: The SHFM was well calibrated to a sample of patients who underwent VT ablation and provided good discrimination of short-term deaths. This model could be useful as a prognostic tool to improve patient selection for VT ablation.

Safety and efficacy of the MitraClip® system for severe mitral regurgitation: a systematic review.

BACKGROUND: The MitraClip® system is a newer percutaneous device that has shown promising results but data on its safety and efficacy in low- and high-surgical risk populations continues to evolve. We performed a systematic review of the published studies reporting the safety and efficacy of MitraClip® implantation for treatment of moderate to severe and severe mitral regurgitation (MR). METHODS: Reviewers independently searched for relevant articles in Medline and abstracted clinical information based on pre-defined criteria and end-points. Patients were classified as low- or high-surgical risk for conventional mitral valve (MV) surgery based on Society of Thoracic Surgeons score, EuroSCORE, or surgeon discretion. Primary safety outcome was 30-day mortality and primary efficacy outcomes were freedom from death, ≥3+ MR, and requirement for MV surgery during follow-up. RESULTS: Immediate and long-term outcomes of 16 studies, including 2980 patients (age 73.7 ± 0.6 years; 63.3% males) receiving the MitraClip®, were analyzed. Acute procedural success rate was 91.4% with a procedural mortality of 0.1%. Mortality at 30 days and long-term (310 days) follow-up was 4.2 and 15.8%, respectively and was significantly higher in the high-risk group (P = 0.003 and 0.019, respectively). Incidence of major procedural adverse outcomes was relatively low with blood transfusion accounting for most events. At follow-up, the number of patients with ≥3+ MR reduced from 96.3% to 14.7% (P < 0.001), and those with NYHA class III/IV reduced from 83.2% to 23.4% (P < 0.001). CONCLUSION: MitraClip® implantation for moderate to severe or severe MR appears to be safe with a very low procedural mortality. There is significant improvement in functional outcomes although long-term mortality is high, especially in high surgical risk patients.

First-in-man clinical implantation and acute pacing performance of a novel subxiphoidal pacemaker system.

BACKGROUND: Intravascular cardiac pacemakers are an established therapy for bradycardic indications. Recently, a new class of leadless pacemakers have mitigated some of the complications related to pacemaker leads. In this study, we evaluate the implantation and performance of a novel extravascular technology that delivers epicardial pacing through a subxiphoidal approach. METHODS: Fifteen patients undergoing non-emergent open-heart surgery were enrolled. A midline incision was made just below the xiphoid process, and substernal tunneling was used to create a pocket for the device and to access the anterior pericardium over the right ventricle. The test device (Calyan Technologies, Oakdale, MN) was temporarily inserted underneath the ribcage and clipped to the xiphoid process. The sensing and pacing electrode (FlexArm) was positioned on the anterior pericardium. Ventricular sensing and pacing capture thresholds were measured. RESULTS: The test device was successfully implanted in all 15 patients. There were no device or procedure-related adverse events. The first five implanted patients had no pacing capture at maximum stimulation intensity. Design changes were made to the device, including different electrode size and shape, and successful ventricular capture was achieved in 9 of the subsequent 10 patients. In these patients, pacing threshold was 3.8 ± 1.6 mA with a pulse width of 0.5 ms. All devices were successfully explanted at the end of the procedure. CONCLUSIONS: In a first-in-human experience with a novel extravascular pacemaker, this study demonstrated the feasibility of pericardial ventricular pacing via a subxiphoidal approach. Further chronic studies are required to evaluate the safety and performance of this novel pacing technology.

Safety and performance of a novel subxiphoidal pacemaker system.

BACKGROUND: Traditional cardiac pacemakers commonly have a range of complications related to the presence of intracardiac leads. A new class of extravascular and leadless pacemakers has recently emerged with the potential to mitigate these complications and expand access to cardiac pacing. The objective of this study is to evaluate the implantation, short-term chronic safety, and performance of a novel subxiphoidal extracardiac pacemaker. METHODS: Normal Yorkshire Cross swine (n = 16) were implanted with the subxiphoidal pacemaker. The pacemaker was inserted through a midline chest incision and clipped to the underside of the sternum, with the stimulation electrode placed on the anterior pericardium. Animals were chronically paced and followed for 90 days post-implant, with periodic measurement of pacing capture threshold (PCT) and electrode impedance. RESULTS: All 16 animals were successfully implanted with the study device. At implant, a consistent average PCT of 2.2 ± 0.4 V at a pulse width of 1.0 ms was observed in all animals, with an average implant impedance of 648 ± 44 Ω. Chronic pacing was programmed at a rate of 60 bpm, an amplitude of 3.4 ± 0.7 V, and a pulse width of 1.0 ms. PCT rose to 4.6 ± 0.8 V at 14 days and stabilized; at 90 days, PCT was 3.8 ± 1.2 V and electrode impedance was 533 ± 105 Ω. All implanted animals completed the study with no clinically significant findings, no clinically significant abnormalities, and with no adverse events that affected animal welfare. CONCLUSIONS: This study demonstrated the safety and feasibility of a novel subxiphoidal extracardiac pacemaker to deliver short-term chronic extravascular therapy. Further studies are required to assess the safety, feasibility, and long-term chronic pacing performance in human subjects.

The active papillary muscle sign in 18F-FDG PET/CT cardiac sarcoidosis exams and its relationship with myocardial suppression.

OBJECTIVE: Papillary muscle (PM) activity may demonstrate true active cardiac sarcoidosis (CS) or mimic CS in 18FDG-PET/CT if adequate myocardial suppression (MS) is not achieved. We aim to examine whether PM uptake can be used as a marker of failed MS and measure the rate of PM activity presence in active CS with different dietary preparations. MATERIALS AND METHODS: We retrospectively reviewed PET/CTs obtained with three different dietary preparations. Diet-A: 24-h ketogenic diet with overnight fasting (n = 94); Diet-B: 18-h fasting (n = 44); and Diet-C: 72-h daytime ketogenic diet with 3-day overnight fasting (n = 98). Each case was evaluated regarding CS diagnosis (negative, positive, and indeterminant) and presence of PM activity. MaxSUV was measured from bloodpool, liver, and the most suppressed normal myocardium. Linear mixed-effects models were used to compare these factors between those with PM activity and those without. RESULTS: PM activity was markedly lower in the Diet-C group compared with others: Diet-C: 6 (6.1%), Diet-A: 36 (38.3%), and Diet-B: 26 (59.1%) (p < 0.001). MyocardiumMaxSUV was higher, and MyocardiummaxSUV/BloodpoolmaxSUV, MyocardiummaxSUV/LivermaxSUV ratios were significantly higher in the cases with PM activity (p < 0.001). Among cases that used Diet-C and had PM activity, 66.7% were positive and 16.7% were indeterminate. If Diet-A or Diet-B was used, those with PM activity had a higher proportion of indeterminate cases (Diet-A: 61.1%, Diet-B: 61.5%) than positive cases (Diet-A: 36.1%, Diet-B: 38.5%). CONCLUSION: Lack of PM activity can be a sign of appropriate MS. PM activity is less common with a specific dietary preparation (72-h daytime ketogenic diet with 3-day overnight fasting), and if it is present with this particular preparation, the likelihood that the case being true active CS might be higher than the other traditional dietary preparations.

Efficacy and benefits of catheter ablation of ventricular premature complexes in patients younger and older than 65 years of age.

OBJECTIVES: Catheter ablation of ventricular premature complexes (VPC) improves clinical status and systolic performance of the left ventricle (LV) in a certain subset of patients; however, whether or not VPC ablation is equally effective in younger (<=65 years) and older (>65 years) patients remains unclear. We aimed to assess the clinical benefits of catheter ablation of VPCs in elderly patients. STUDY DESIGN: Fifty-one consecutive patients (66±10 years, 49 male) who underwent catheter ablation for symptomatic VPCs were included into the study. Twenty-seven patients were aged >65 years and 24 patients <=65 years. Frequency of VPCs per total heart beats by 24-hour Holter monitoring, LV ejection fraction (LVEF) and end-systolic diameters (LVEDD) were evaluated before and 6±3 months after ablation. RESULTS: The pre-ablation 24-hour VPC burden and VPC number were significantly higher in patients >65 years compared to those <=65 years (31±15.3 vs. 21.9±12.6, p=0.04 and 34493±21226 vs. 23554±13792, p=0.026, respectively). At the follow-up after catheter ablation, the mean VPC burden had decreased to 9.1±10.3% (p<0.001) in patients >65 years and to 3.8±7.1 (p<0.001) in patients <=65 years. Mean LVEF showed a significant increase in both groups after ablation (43.4±10.4 vs. 51.5±8.2, p=0.005 for age >65 years and 40.8±13.2 vs. 49.5±11.8, p=0.003 for age <=65 years). The improvement in LVEF was accompanied by a significant decrease in LVEDD (p=0.032 for age >65 years and p=0.047 for <=65 years). CONCLUSION: Catheter ablation is effective for treatment of frequent VPCs in all age groups.

Risk of Adverse Outcomes Associated With Cardiac Sarcoidosis Diagnostic Schemes.

BACKGROUND: Multiple cardiac sarcoidosis (CS) diagnostic schemes have been published. OBJECTIVES: This study aims to evaluate the association of different CS diagnostic schemes with adverse outcomes. The diagnostic schemes evaluated were 1993, 2006, and 2017 Japanese criteria and the 2014 Heart Rhythm Society criteria. METHODS: Data were collected from the Cardiac Sarcoidosis Consortium, an international registry of CS patients. Outcome events were any of the following: all-cause mortality, left ventricular assist device placement, heart transplantation, and appropriate implantable cardioverter-defibrillator therapy. Logistic regression analysis evaluated the association of outcomes with each CS diagnostic scheme. RESULTS: A total of 587 subjects met the following criteria: 1993 Japanese (n = 310, 52.8%), 2006 Japanese (n = 312, 53.2%), 2014 Heart Rhythm Society (n = 480, 81.8%), and 2017 Japanese (n = 112, 19.1%). Patients who met the 1993 criteria were more likely to experience an event than patients who did not (n = 109 of 310, 35.2% vs n = 59 of 277, 21.3%; OR: 2.00; 95% CI: 1.38-2.90; P < 0.001). Similarly, patients who met the 2006 criteria were more likely to have an event than patients who did not (n = 116 of 312, 37.2% vs n = 52 of 275, 18.9%; OR: 2.54; 95% CI: 1.74-3.71; P < 0.001). There was no statistically significant association between the occurrence of an event and whether a patient met the 2014 or the 2017 criteria (OR: 1.39; 95% CI: 0.85-2.27; P = 0.18 or OR: 1.51; 95% CI: 0.97-2.33; P = 0.067, respectively). CONCLUSIONS: CS patients who met the 1993 and the 2006 criteria had higher odds of adverse clinical outcomes. Future research is needed to prospectively evaluate existing diagnostic schemes and develop new risk models for this complex disease.

Amiodarone Use and All-Cause Mortality in Patients With a Continuous-Flow Left Ventricular Assist Device.

Background Atrial and ventricular arrhythmias are commonly encountered in patients with advanced heart failure, with amiodarone being the most commonly used antiarrhythmic drug in continuous-flow left ventricular assist device (CF-LVAD) recipients. The purpose of this study was to assess the impact of amiodarone use on long-term all-cause mortality in ptients with a CF-LVAD. Methods and Results A retrospective multicenter study of CF-LVAD was conducted at 5 centers including all CF-LVAD implants from 2007 to 2015. Patients were stratified based on pre-CF-LVAD implant amiodarone use. Additional use of amiodarone after CF-LVAD implantation was also evaluated. Primary outcome was all-cause mortality during long-term follow-up. Kaplan-Meier curves were used to assess survival outcomes. Multivariable Cox regression was used to identify predictors of outcomes. Propensity matching was done to address baseline differences. A total of 480 patients with a CF-LVAD (aged 58±13 years, 81% men) were included. Of these, 170 (35.4%) were on chronic amiodarone therapy at the time of CF-LVAD implant, and 310 (64.6%) were not on amiodarone. Rate of all-cause mortality over the follow-up period was 32.9% in the amiodarone group compared with 29.6% in those not on amiodarone (P=0.008). Similar results were noted in the propensity-matched group (log-rank, P=0.04). On multivariable Cox regression analysis, amiodarone use at baseline was independently associated with all-cause mortality (hazard ratio, 1.68 [95% CI, 1.1-2.5]; P=0.01). Conclusions Amiodarone use was associated with significantly increased rates of all-cause mortality in CF-LVAD recipients. Earlier interventions for arrhythmias to avoid long-term amiodarone exposure may improve long-term outcomes in CF-LVAD recipients and needs further study.