ACCF/HRS/AHA/ASE/HFSA/SCAI/SCCT/SCMR 2013 appropriate use criteria for implantable cardioverter-defibrillators and cardiac resynchronization therapy: a report of the American College of Cardiology Foundation appropriate use criteria task force, Heart Rhythm Society, American Heart Association, American Society of Echocardiography, Heart Failure Society of America, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance

A Look at Primary and Secondary Prevention in the Elderly: The Two Sides of the Same Coin

The global population is experiencing an aging trend; however, this increased longevity is not necessarily accompanied by improved health in older age. A significant consequence of this demographic shift is the rising prevalence of multiple chronic illnesses, posing challenges to healthcare systems worldwide. Aging is a major risk factor for multimorbidity, which marks a progressive decline in resilience and a dysregulation of multisystem homeostasis. Cardiovascular risk factors, along with aging and comorbidities, play a critical role in the development of heart disease. Among comorbidities, age itself stands out as one of the most significant risk factors for cardiovascular disease, with its prevalence and incidence notably increasing in the elderly population. However, elderly individuals, especially those who are frail and have multiple comorbidities, are under-represented in primary and secondary prevention trials aimed at addressing traditional cardiovascular risk factors, such as hypercholesterolemia, diabetes mellitus, and hypertension. There are concerns regarding the optimal intensity of treatment, taking into account tolerability and the risk of drug interactions. Additionally, uncertainty persists regarding therapeutic targets across different age groups. This article provides an overview of the relationship between aging and cardiovascular disease, highlighting various cardiovascular prevention issues in the elderly population.

Speckle Tracking Echocardiography in Patients with Non-Ischemic Dilated Cardiomyopathy Who Undergo Cardiac Resynchronization Therapy: A Narrative Review

Non-ischemic dilated cardiomyopathy (DCM) represents a significant cause of heart failure, defined as the presence of left ventricular (LV) dilatation and systolic dysfunction unexplained solely by abnormal loading conditions or coronary artery disease. Cardiac resynchronization therapy (CRT) has emerged as a cornerstone in the management of heart failure, particularly in patients with DCM. However, identifying patients who will benefit the most from CRT remains challenging. Speckle tracking echocardiography (STE) has garnered attention as a non-invasive imaging modality that allows for the quantitative assessment of myocardial mechanics, offering insights into LV function beyond traditional echocardiographic parameters. This comprehensive review explores the role of STE in guiding patient selection and optimizing outcomes in CRT for DCM. By assessing parameters such as LV strain, strain rate, and dyssynchrony, STE enables a more precise evaluation of myocardial function and mechanical dyssynchrony, aiding in the identification of patients who are most likely to benefit from CRT. Furthermore, STE provides valuable prognostic information and facilitates post-CRT optimization by guiding lead placement and assessing response to therapy. Through an integration of STE with CRT, clinicians can enhance patient selection, improve procedural success rates, and ultimately, optimize clinical outcomes in patients with DCM. This review underscores the pivotal role of STE in advancing personalized management strategies for DCM patients undergoing CRT.

Do Implantable Cardioverter-Defibrillators Prevent Sudden Cardiac Death in End-Stage Renal Disease Patients on Dialysis?

Chronic kidney disease patients appear to be predisposed to heart rhythm disorders, including atrial fibrillation/atrial flutter, ventricular arrhythmias, and supraventricular tachycardias, which increase the risk of sudden cardiac death. The pathophysiological factors underlying arrhythmia and sudden cardiac death in patients with end-stage renal disease are unique and include timing and frequency of dialysis and dialysate composition, vulnerable myocardium, and acute proarrhythmic factors triggering asystole. The high incidence of sudden cardiac deaths suggests that this population could benefit from implantable cardioverter-defibrillator therapy. The introduction of implantable cardioverter-defibrillators significantly decreased the rate of all-cause mortality; however, the benefits of this therapy among patients with chronic kidney disease remain controversial since the studies provide conflicting results. Electrolyte imbalances in haemodialysis patients may result in ineffective shock therapy or the appearance of non-shockable underlying arrhythmic sudden cardiac death. Moreover, the implantation of such devices is associated with a risk of infections and central venous stenosis. Therefore, in the population of patients with heart failure and severe renal impairment, periprocedural risk and life expectancy must be considered when deciding on potential device implantation. Harmonised management of rhythm disorders and renal disease can potentially minimise risks and improve patients' outcomes and prognosis.

Inter-American Society of Cardiology (CIFACAH-ELECTROSIAC) and Latin-American Heart Rhythm Society (LAHRS): multidisciplinary review on the appropriate use of implantable cardiodefibrillator in heart failure with reduced ejection fraction

BACKGROUND

Our main objective was to present a multidisciplinary review on the epidemiology of sudden cardiac death (SCD) and the tools that could be used to identify malignant ventricular arrhythmias (VAs) and to perform risk stratification. In addition, indications and contraindications for the use of implantable cardioverter defibrillator (ICD) in general and in special populations including the elderly and patients with chronic kidney disease (CKD) are also given.

METHODS

An expert group from the Inter American Society of Cardiology (IASC), through their HF Council (CIFACAH) and Electrocardiology Council (ElectroSIAC), together with the Latin American Heart Rhythm Society (LAHRS), reviewed and discussed the literature regarding the appropriate use of an ICD in people with heart failure (HF) with reduced ejection fraction (HFpEF). Indications and contraindications for the use of ICD are presented in this multidisciplinary review.

RESULTS

Numerous clinical studies have demonstrated the usefulness of ICD in both primary and secondary prevention of SCD in HFpEF. There are currently precise indications and contraindications for the use of these devices.

CONCLUSIONS

In some Latin American countries, a low rate of implantation is correlated with low incomes, but this is not the case for all Latin America. Determinants of the low rates of ICD implantation in many Latin American countries are still a matter of research. VA remains one of the most common causes of cardiovascular death associated with HFrEF and different tools are available for stratifying the risk of SCD in this population.

Defibrillator exchange in the elderly

Background

Implantable cardioverter-defibrillator (ICD) therapy in elderly patients is controversial because survival benefits might be attenuated by nonarrhythmic causes of death.

Objective

The purpose of this study was to investigate the outcome of septuagenarians and octogenarians after ICD generator exchange (GE).

Methods

A total of 506 patients undergoing elective GE were analyzed to determine the incidence of ICD shocks and/or survival after GE. Patients were divided into a septuagenarian group (age 70-79 years) and an octogenarian group (age ≥80 years). The primary endpoint was death from any cause. Secondary endpoints were survival after appropriate ICD shock and death without experiencing ICD shocks after GE ("prior death").

Results

The association of the ICD with all-cause mortality and arrhythmic death was determined for septuagenarians and octogenarians. Comparing both groups, similar left ventricular ejection fraction (35.6% ± 11.2% vs 32.4% ± 8.9%) and baseline prevalence of New York Heart Association functional class III or IV heart failure (17.1% vs 14.7%) were found. During the entire follow-up period of the study, 42.5% of patients in the septuagenarian group died compared to 79% in the octogenarian group (P <.01). Prior death was significantly more frequent in both age groups than were appropriate ICD shocks. Predictors of mortality were common in both groups and included advanced heart failure, peripheral arterial disease, and renal failure.

Conclusion

In clinical practice, decision-making for ICD GE among the elderly should be considered carefully for individual patients.

Clinical, electrocardiographic, and echocardiographic parameters associated with the development of pacing and implantable cardioverter-defibrillator indication in patients with transthyretin amyloid cardiomyopathy

AIMS

This study aimed to identify factors for attention leading to future pacing device implantation (PDI) and reveal the necessity of prophylactic PDI or implantable cardioverter-defibrillator (ICD) implantation in transthyretin amyloid cardiomyopathy (ATTR-CM) patients.

METHODS AND RESULTS

This retrospective single-center observational study included consecutive 114 wild-type ATTR-CM (ATTRwt-CM) and 50 hereditary ATTR-CM (ATTRv-CM) patients, neither implanted with a pacing device nor fulfilling indications for PDI at diagnosis. As a study outcome, patient backgrounds were compared with and without future PDI, and the incidence of PDI in each conduction disturbance was examined. Furthermore, appropriate ICD therapies were investigated in all 19 patients with ICD implantation. PR-interval ≥220 msec, interventricular septum (IVS) thickness ≥16.9 mm, and bifascicular block were significantly associated with future PDI in ATTRwt-CM patients, and brain natriuretic peptide ≥35.7 pg/mL, IVS thickness ≥11.3 mm, and bifascicular block in ATTRv-CM patients. The incidence of subsequent PDI in patients with bifascicular block at diagnosis was significantly higher than that of normal atrioventricular (AV) conduction in both ATTRwt-CM [hazard ratio (HR): 13.70, P = 0.019] and ATTRv-CM (HR: 12.94, P = 0.002), whereas that of patients with first-degree AV block was neither (ATTRwt-CM: HR: 2.14, P = 0.511, ATTRv-CM: HR: 1.57, P = 0.701). Regarding ICD, only 2 of 16 ATTRwt-CM and 1 of 3 ATTRv-CM patients received appropriate anti-tachycardia pacing or shock therapy, under the number of intervals to detect for ventricular tachycardia of 16-32.

CONCLUSIONS

According to our retrospective single-center observational study, prophylactic PDI did not require first-degree AV block in both ATTRwt-CM and ATTRv-CM patients, and prophylactic ICD implantation was also controversial in both ATTR-CM. Larger prospective, multi-center studies are necessary to confirm these results.

Characteristics and survival of patients diagnosed with cardiac sarcoidosis: A case series

Background

Sarcoidosis is a multiorgan system granulomatous disease of unknown etiology. It is hypothesized that a combination of environmental, occupational, and/or infectious factors provoke an immunological response in genetically susceptible individuals, resulting in a diversity of manifestations throughout the body. In the United States, cardiac sarcoidosis (CS) is diagnosed in 5% of patients with systemic sarcoidosis, however, autopsy results suggest that cardiac involvement may be present in > 50% of patients. CS is debilitating and significantly decreases quality of life and survival. Currently, there are no gold-standard clinical diagnostic or monitoring criteria for CS.

Methods

We identified patients with a diagnosis of sarcoidosis who were seen at the Simmons Center from 2007 to 2020 who had a positive finding of CS documented with cardiovascular magnetic resonance (CMR) and/or endomyocardial biopsy as found in the electronic health record. Medical records were independently reviewed for interpretation and diagnostic features of CS including late gadolinium enhancement (LGE) patterns, increased signal on T2-weighted imaging, and non-caseating granulomas, respectively. Extracardiac organ involvement, cardiac manifestations, comorbid conditions, treatment history, and vital status were also abstracted.

Results

We identified 44 unique patients with evidence of CS out of 246 CMR reports and 9 endomyocardial biopsy pathology reports. The first eligible case was diagnosed in 2007. The majority of patients (73%) had pulmonary manifestations, followed by hepatic manifestations (23%), cutaneous involvement (23%), and urolithiasis (20%). Heart failure was the most common cardiac manifestation affecting 59% of patients. Of these, 39% had a documented left ventricular ejection fraction of < 50% on CMR. Fifty eight percent of patients had a conduction disease and 44% of patients had documented ventricular arrhythmias. Pharmacotherapy was usually initiated for extracardiac manifestations and 93% of patients had been prescribed prednisone. ICD implantation occurred in 43% of patients. Patients were followed up for a median of 5.4 (IQR: 2.4-8.5) years. The 10-year survival was 70%. In addition to age, cutaneous involvement was associated with an increased risk of death (age-adjusted OR 8.47, 95% CI = 1.11-64.73).

Conclusion

CMR is an important tool in the non-invasive diagnosis of CS. The presence of LGE on CMR in a pattern consistent with CS has been shown to be a predictor of mortality and likely contributed to a high proportion of patients undergoing ICD implantation to decrease risk of sudden cardiac death.

Clinical implications

Additional studies are necessary to develop robust criteria for the diagnosis of CS with CMR, assess the benefit of serial imaging for disease monitoring, and evaluate the effect of immunosuppression on disease progression.

Smaller left ventricular end-systolic diameter and lower ejection fraction at baseline associated with greater ejection fraction improvement after revascularization among patients with left ventricular dysfunction

Objectives

To investigate the predictive roles of pre-operative left ventricular (LV) size and ejection fraction (EF) in EF improvement and outcome following revascularization in patients with coronary artery disease (CAD) and LV dysfunction.

Background

Revascularization may improve EF and long-term outcomes of patients with LV dysfunction. However, the determinants of EF improvement have not yet been investigated comprehensively.

Materials and methods

Patients with EF measurements before and 3 months after revascularization were enrolled in a cohort study (No. ChiCTR2100044378). All patients had baseline EF ≤ 40%. EF improvement was defined as absolute increase in EF > 5%. According to LV end-systolic diameter (LVESD) (severely enlarged or not) and EF (≤35% or of 36–40%) at baseline, patients were categorized into four groups.

Results

A total of 939 patients were identified. A total of 549 (58.5%) had EF improved. Both LVESD [odds ratio (OR) per 1 mm decrease, 1.05; 95% CI, 1.04–1.07; P < 0.001] and EF (OR per 1% decrease, 1.06; 95% CI, 1.03–1.10; P < 0.001) at baseline were predictive of EF improvement after revascularization. Patients with LVESD not severely enlarged and EF ≤ 35% had higher odds of being in the EF improved group in comparison with other three groups both in unadjusted and adjusted analysis (all P < 0.001). The median follow-up time was 3.5 years. Patients with LVESD not severely enlarged and EF ≤ 35% had significantly lower risk of all-cause death in comparison with patients with LVESD severely enlarged and EF ≤ 35% [hazard ratio (HR), 2.73; 95% CI, 1.28–5.82; P = 0.009], and tended to have lower risk in comparison with patients with LVESD severely enlarged and EF of 36–40% (HR, 2.00; 95% CI, 0.93–4.27; P = 0.074).

Conclusion

Among CAD patients with reduced EF (≤ 40%) who underwent revascularization, smaller pre-operative LVESD and lower EF had greatest potential to have EF improvement and better outcome. Our findings imply the indication for revascularization in patients with LV dysfunction who presented with lower EF but smaller LV size.

Extent of Ejection Fraction Improvement After Revascularization Associated with Outcomes Among Patients with Ischemic Left Ventricular Dysfunction

Purpose

Ejection fraction (EF) has been reported to be a major predictor of improved survival in patients with heart failure. However, it is largely unknown whether the extent of improvement in EF affects the subsequent risk of mortality. This study sought to investigate change in EF after revascularization and the implication of these changes on clinical outcomes among patients with ischemic left ventricular dysfunction.

Patients and Methods

We conducted a cohort study (No. ChiCTR2100044378) of patients with reduced EF (≤40%) who received revascularization and had EF reassessment by echocardiography 3 months after revascularization. Patients were categorized according to the absolute change in EF: 1) EF worsened group (absolute decrease in EF >5%); 2) EF unchanged group (absolute change in EF −5% to 5%); 3) EF improved group (absolute increase in EF >5%).

Results

Of 974 patients, 84 (8.6%) had EF worsened, 317 (32.5%) had EF unchanged and 573 (58.8%) had EF improved. The median follow-up time was 3.5 years, during which 143 patients died. For each 5-unit increments in EF, the risk of death decreased by 20% (hazard ratio, HR, per 5% increases, 0.80; 95% CI, 0.73–0.86; P<0.001). Compared with EF improvement group, patients with EF worsened (HR, 3.35; 95% CI, 2.07–5.42; P<0.001) and patients with EF unchanged (HR, 2.05; 95% CI, 1.40–3.01; P<0.001) had significantly higher risk of all-cause death.

Conclusion

Changes in EF were inversely associated with the risk of mortality. The extent of EF improvement after revascularization might be a potential factor which defines clinical outcomes.

Effects of medically generated electromagnetic interference from medical devices on cardiac implantable electronic devices: A review

As cardiac implantable electronic devices (CIED) become more prevalent, it is important to acknowledge potential electromagnetic interference (EMI) from other sources, such as internal and external electronic devices and procedures and its effect on these devices. EMI from other sources can potentially inhibit pacing and trigger shocks in permanent pacemakers (PPM) and implantable cardioverter defibrillators (ICD), respectively. This review analyzes potential EMI amongst CIED and left ventricular assist device, deep brain stimulators, spinal cord stimulators, transcutaneous electrical nerve stimulators, and throughout an array of procedures, such as endoscopy, bronchoscopy, and procedures involving electrocautery. Although there is evidence to support EMI from internal and external devices and during procedures, there is a lack of large multicenter studies, and, as a result, current management guidelines are based primarily on expert opinion and anecdotal experience. We aim to provide a general overview of PPM/ICD function, review documented EMI effect on these devices, and acknowledge current management of CIED interference.

Arrhythmic sudden death survival prediction using deep learning analysis of scarring in the heart

Sudden cardiac death from arrhythmia is a major cause of mortality worldwide. Here, we develop a novel deep learning (DL) approach that blends neural networks and survival analysis to predict patient-specific survival curves from contrast-enhanced cardiac magnetic resonance images and clinical covariates for patients with ischemic heart disease. The DL-predicted survival curves offer accurate predictions at times up to 10 years and allow for estimation of uncertainty in predictions. The performance of this learning architecture was evaluated on multi-center internal validation data and tested on an independent test set, achieving concordance index of 0.83 and 0.74, and 10-year integrated Brier score of 0.12 and 0.14. We demonstrate that our DL approach with only raw cardiac images as input outperforms standard survival models constructed using clinical covariates. This technology has the potential to transform clinical decision-making by offering accurate and generalizable predictions of patient-specific survival probabilities of arrhythmic death over time.

Trends in Use of Single- vs Dual-Chamber Implantable Cardioverter-Defibrillators Among Patients Without a Pacing Indication, 2010-2018

IMPORTANCE

Use of dual-chamber implantable cardioverter-defibrillator (ICD) systems among patients without a pacing indication is an example of low-value care given higher procedural risks, higher costs, and little evidence for benefit from an atrial lead. However, variation in the use of dual-chamber systems was present among patients without a pacing indication.

OBJECTIVE

To examine the temporal trends and hospital variation in use of single- and dual-chamber ICD implantation among patients without a pacing indication undergoing first-time ICD implantation.

DESIGN, SETTING, AND PARTICIPANTS

A multicenter cross-sectional study was conducted using the US National Cardiovascular Data Registry ICD Registry. A total of 266 182 patients undergoing initial implantation of a single- or dual-chamber transvenous ICD without a bradycardia pacing indication, class I or II cardiac resynchronization therapy indication, or history of atrial fibrillation or atrial flutter were included. The study was conducted from April 1, 2010, to December 31, 2018; data analysis was performed from October 19, 2020, to January 5, 2022.

EXPOSURES

Implantation of a single- or dual-chamber ICD.

MAIN OUTCOMES AND MEASURES

Temporal trends among patients undergoing single- vs dual-chamber ICDs were determined using the Cochran-Armitage trend test, and hospital-level variation using adjusted hospital median odds ratios was examined.

RESULTS

A total of 266 182 patients (single-chamber ICD, 134 925; dual-chamber ICD, 131 257) were included in this analysis; mean (SD) age was 58.0 (14.0) years and 91 990 patients (68.2%) were men. The use of dual-chamber ICDs decreased from 64.7% (n = 15 694) in 2010 to 42.2% (n = 9762) in 2018 (P < .001). Adjusted for patient characteristics, the median hospital-level proportion of single-chamber ICDs increased from 42.9% (95% CI, 42.6%-45.0%) in 2010 to 50.0% (95% CI, 47.8%-51.0%) in 2018. The median odds ratio for the use of dual-chamber ICDs, adjusted for patient characteristics, was 1.6 (95% CI, 1.6-1.8) in 2010 and 1.5 (95% CI, 1.5-1.8) in 2018, indicating decreasing but persistent variation in use.

CONCLUSIONS AND RELEVANCE

In this national study of US patients undergoing first-time ICD implantation without a clinical indication for an atrial lead, the use of dual-chamber devices decreased. However, institutional variability in the use of atrial leads persists, suggesting differences in individual or institutional cultures of real-world practice and opportunity to reduce this low-value practice.

Variation in regional implantation patterns of cardiac implantable electronic device in Switzerland

Introduction

There is a substantial geographical variation in the rates of pacemaker (PM), implantable cardioverter defibrillator (ICD), and cardiac resynchronization therapy (CRT) device implantation across European countries. We assessed the extent of regional variation and potential determinants of such variation.

Methods

We conducted a population-based analysis using discharge data for PM/ICD/CRT implantations from all Swiss acute care hospitals during 2013–2016. We derived hospital service areas (HSA) by analyzing patient flows. We calculated age- and sex-standardized rates and quantified variation using the extremal quotient (EQ) and the systemic component of variation (SCV). We estimated the reduction in variance of crude implantation rates across HSAs using multilevel regression models, with incremental adjustment for age and sex, language, socioeconomic factors, population health, diabetes mellitus, and the density of cardiologists on the HSA level.

Results

We analyzed implantations of 8129 PM, 1461 ICD, and 1411 CRT from 25 Swiss HSAs. The mean age- and sex-standardized implantation rate was 29 (range 8–57) per 100,000 persons for PM, 5 (1–9) for ICD, and 5 (2–8) for CRT. There was a very high variation in PM (EQ 7.0; SCV 12.6) and ICD (EQ 7.2; SCV 11.3) and a high variation in CRT implantation rates (EQ 3.9; SCV 7.1) across HSAs. Adjustments for age and sex, language, socioeconomic factors, population health, diabetes mellitus, and density of cardiologists explained 94% of the variance in ICD and 87.5% of the variance in CRT implantation rates, but only 36.3% of the variance in PM implantation rates. Women had substantially lower PM/ICD/CRT implantation rates than men.

Conclusion

Switzerland has a very high regional variation in PM/ICD implantation and a high variation in CRT implantation rates. Women had substantially lower implantation rates than men. A large share of the variation in PM procedure rates remained unexplained which might reflect variations in physicians’ preferences and practices.

Electrocardiographic markers of cardiac resynchronization therapy response: delayed time to intrinsicoid deflection onset in lateral leads

Cardiac resynchronization therapy (CRT) has emerged as an important intervention for patients with heart failure (HF) with reduced ejection fraction and delayed ventricular activation. In these patients, CRT has demonstrated to improve quality of life, promote reverse left ventricular (LV) remodeling, reduce HF hospitalizations, and extend survival. However, despite advancements in our understanding of CRT, a significant number of patients do not respond to this therapy. Several invasive and non-invasive parameters have been assessed to predict response to CRT, but the electrocardiogram (ECG) has remained as the prevailing screening method albeit with limitations. Ideally, an accurate, simple, and reproducible ECG marker or set of markers would dramatically overcome the current limitations. We describe the clinical utility of an old ECG parameter that can estimate ventricular activation delay: the onset to intrinsicoid deflection (ID). Based on the concept of direct measurement of ventricular activation time (intrinsic deflection onset), time to ID onset measures on the surface ECG the time that the electrical activation time takes to reach the area subtended by the corresponding surface ECG lead. Based on this principle, the time to ID on the lateral leads can estimate the delay activation to the lateral LV wall and can be used as a predictor for CRT response, particularly in patients with non-specific intraventricular conduction delay or in patients with left bundle branch block and QRS < 150 ms. The aim of this review is to present the current evidence and potential use of this ECG parameter to estimate LV activation and predict CRT response.

Displaced AICD Lead Presenting as Hiccups: A Rare Complication

Ventricular fibrillation can lead to sudden cardiac death. Automatic implantable cardioverter defibrillator (AICD) devices have shown to be highly successful in the termination of these arrhythmias and are a first-line modality of treatment for the prevention of sudden cardiac death. We present the case of a 69-year-old female with a history of paroxysmal atrial fibrillation on anticoagulation with apixaban and rate controlled with metoprolol who presented from home with a chief complaint of hiccups. She had a prior admission to the hospital after she was found to have monomorphic ventricular tachycardia during a nuclear stress test. A cardiac work-up including cardiac catheterization and cardiac magnetic resonance imaging did not show any evidence of significant coronary artery disease or reversible cardiomyopathy. The patient underwent successful placement of a single chamber ICD and was discharged home. Twelve weeks after placement of the AICD, the patient was lifting furniture and experienced sudden onset of hiccups. A chest X-ray showed displacement of the AICD lead from the right ventricular apex to the superior vena cava. The patient underwent lead repositioning with complete resolution of her hiccups. The etiology hiccups was suspected to be secondary to irritation of the right phrenic nerve which travels along the anterolateral border of the superior vena cava. We present the case of hiccups following ICD lead displacement. This serves to highlight a rare complication of ICD displacement that healthcare providers should consider when patients with recently placed ICD devices complain of hiccups.

Supraventricular Tachycardia Causing Left Ventricular Dysfunction

There is limited evidence on characterization and natural history of supraventricular tachycardia (SVT)-induced left ventricular (LV) dysfunction. The aim of this work was to characterize clinical features and long-term evolution of SVT-induced LV dysfunction. Patients consecutively admitted with sustained SVT and heart rate >100 bpm as the only known cause of a new onset LV systolic dysfunction (i.e., LV ejection fraction [EF] <50%) were analyzed. Patients were then revaluated periodically. Recovered LVEF (i.e., ≥50%) and a composite of death, heart transplant or first episode of major ventricular arrhythmias were evaluated as study end-points. We enrolled 83 patients. After SVT therapy, 56 (67%) showed a recovered LVEF at the last follow-up of median 54 (interquartile range 36 to 87) months. Seventeen (30%) of those patients had a temporary new drop in LVEF during follow-up associated to high-rate SVT relapse. At presentation, patients with recovered LVEF were younger (52 vs 67 years respectively, p <0.001) and had higher LVEF (34% vs 27% respectively, p = 0.005) compared to non-recovered LVEF patients. Finally, 4% of recovered LVEF patients vs 26% of nonrecovered LVEF patients experienced death/heart transplant/major ventricular arrhythmias during follow-up (p = 0.004). In conclusion, after almost 5 years of follow-up, two-thirds of patients with high-rate SVT causing a newly diagnosed LV systolic dysfunction recovered and maintained normal LV function after SVT control, with a subsequent benign outcome. Long term individual surveillance is required in those patients, as arrhythmic recurrences and new drops in LVEF are common in the long term.

Increased left and right atrial volume indices are associated with decreased survival times post-cardiac arrest

BACKGROUND

Left and right atrial volume indices (LAVI and RAVI) are markers of cardiac remodeling. LAVI and RAVI are associated with worse outcomes in other cardiac conditions. This study aimed to determine the associations of these atrial volume indices with survival time post-cardiac arrest.

METHODS

This was a single center, retrospective study of patients with a sudden cardiac arrest event during index hospitalization from 2014-2018 based on pre-arrest parameters. The analysis was stratified based on whether a pulseless ventricular tachycardia/ventricular fibrillation (pVT/VF) event or a pulseless electrical activity (PEA)/asystole event occurred. Cox proportional hazards regression and model selection with best subsets approach evaluated the association of atrial volume parameters with survival times in the context of other covariates.

RESULTS

Of 305 patients studied (64 ± 14 years, 37% female), the mean LAVI was 34.0 ± 15.8 mL/m² (based on 162 reliable measurements), and mean RAVI was 25.0 ± 15.6 mL/m² (based on 163 measurements). Increased atrial volume indices were most strongly associated with survival in patients who had sustained pVT/VF (LAVI HR 0.47, 95% CI 0.25-0.90, p = 0.020; RAVI HR 0.57, 95% CI 0.30-1.05, p = 0.074). In multivariable best subsets Cox regression with LAVI, RAVI, and 13 other scaled covariates, LAVI < 34 ml/m² was by far the best single predictor of survival (p < 0.0001), and the next best predictor was the absence of pulmonary hypertension.

CONCLUSION

Among patients with cardiac arrest from ventricular arrhythmias, those with no more than mild left atrial enlargement pre-arrest by LAVI measurement had the best prognosis. Additional studies are indicated to validate the importance of this finding for clinical management decisions.

CONDENSED ABSTRACT

In patients with sudden cardiac arrest associated with ventricular arrhythmias, a left atrial volume index (LAVI) < 34 mL/m² prior to the arrest had the strongest association with survival among fifteen candidate predictors. Pulmonary hypertension was more common in patients with an elevated right atrial volume index (RAVI), and the absence of pulmonary hypertension was the next best pre-arrest parameter predictive of survival. Larger studies are indicated to validate the use of LAVI for clinical management decisions in this condition.

Diabetes Associated With Greater Ejection Fraction Improvement After Revascularization in Patients With Reduced Ejection Fraction

Objectives: To investigate the association between diabetes mellitus (DM) and ejection fraction (EF) improvement following revascularization in patients with coronary artery disease (CAD) and left ventricular (LV) dysfunction.

Background: Revascularization may improve outcomes of patients with LV dysfunction by improvement of EF. However, the determinants of EF improvement have not yet been investigated comprehensively.

Method: A cohort study (No. ChiCTR2100044378) of patient with repeated EF measurements after revascularization was performed. All patients had baseline EF ≤40%. Patients who had EF reassessment 3 months after revascularization were enrolled. Patients were categorized into EF unimproved (absolute increase in EF ≤5%) and improved group (absolute increase in EF >5%).

Results: A total of 974 patients were identified. 573 (58.8%) had EF improved. Patients with DM had greater odds of being in the improved group (odds ratio [OR], 1.42; 95% CI, 1.07–1.89; P = 0.014). 333 (34.2%) patients with DM had a greater extent of EF improvement after revascularization (10.5 ± 10.4 vs. 8.1 ± 11.2%; P = 0.002) compared with non-diabetic patients. The median follow-up time was 3.5 years. DM was associated with higher risk of overall mortality (hazard ratio [HR], 1.46; 95% CI, 1.02–2.08; P = 0.037). However, in EF improved group, the risk was similar between diabetic and non-diabetic patients (HR, 1.36; 95% CI, 0.80–2.32; P = 0.257).

Conclusions: Among patients with reduced EF, DM was associated with greater EF improvement after revascularization. Revascularization in diabetic patients might partially attenuate the impact of DM on adverse outcomes. Our findings imply the indication for revascularization in patients with LV dysfunction who present with DM.

Dopamine in Idiopathic Polymorphic Ventricular Tachycardia/Ventricular Fibrillation

The role of medical therapy in the treatment of idiopathic polymorphic ventricular tachycardia (IPMVT) and idiopathic ventricular fibrillation (IVF) is not well established. Current medications in use include amiodarone, lidocaine, isoproterenol, verapamil, and quinidine. However, the use of dopamine for controlling such arrhythmias has never been described. We present an interesting case of IPMVT/IVF storm induced by short-coupled premature ventricular contractions. The arrhythmia was terminated acutely using dopamine infusion and was suppressed chronically using verapamil.

Assessment of primary prevention patients receiving an ICD - Systematic evaluation of ATP: APPRAISE ATP

Background

The value of antitachycardia pacing (ATP) in the overall cohort of primary prevention patients who receive implantable cardioverter-defibrillators (ICDs) remains uncertain. ATP success reported in prior trials potentially included a large number of patients receiving unnecessary ATP for arrhythmias that may have self-terminated owing to the prematurity of the intervention. Although some patients derive benefit from initial ATP in terminating rapid ventricular arrhythmias and thereby preventing shocks, there are limited data allowing us to identify those patients a priori.

Objective

The purpose of APPRAISE ATP is to understand the role of ATP in primary prevention patients currently indicated for ICD therapy in a large prospective randomized controlled trial with modern programming parameters.

Methods

The study is a global, prospective, randomized, multicenter clinical trial conducted at up to 150 sites globally, enrolling approximately 2600 subjects The primary endpoint of the trial is time to first all-cause shock in a 2-arm study with an equivalent study design in which the incidence of all-cause shocks will be compared between primary prevention subjects programmed with shocks only vs subjects programmed to standard therapy (ATP and shock).

Results

An Electrogram and Device Interrogation Core Laboratory will review interrogation data to determine primary endpoints that occur in APPRAISE ATP. Their decisions are based on independent physician review of the data from device interrogation.

Conclusion

The ultimate purpose of the study is to aid clinicians in the selection of ICD technologies based on hard endpoint evidence across the spectrum of indications for primary prevention implantation.

Progress and challenges in the treatment of cardiac amyloidosis: a review of the literature

Cardiac amyloidosis is a restrictive cardiomyopathy determined by the accumulation of amyloid, which is represented by misfolded protein fragments in the cardiac extracellular space. The main classification of systemic amyloidosis is determined by the amyloid precursor proteins causing a very heterogeneous disease spectrum, but the main types of amyloidosis involving the heart are light chain (AL) and transthyretin amyloidosis (ATTR). AL, in which the amyloid precursor is represented by misfolded immunoglobulin light chains, can involve almost any system carrying the worst prognosis among amyloidosis patients. This has however dramatically improved in the last few years with the increased usage of the novel therapies such as proteasome inhibitors and haematopoietic cell transplantation, in the case of timely diagnosis and initiation of treatment. The treatment for AL is directed by the haematologist working closely with the cardiologist when there is a significant cardiac involvement. Transthyretin (TTR) is a protein that is produced by the liver and is involved in the transportation of thyroid hormones, especially thyroxine and retinol binding protein. ATTR results from the accumulation of transthyretin amyloid in the extracellular space of different organs and systems, especially the heart and the nervous system. Specific therapies for ATTR act at various levels of TTR, from synthesis to deposition: TTR tetramer stabilization, oligomer aggregation inhibition, genetic therapy, amyloid fibre degradation, antiserum amyloid P antibodies, and antiserum TTR antibodies. Treatment of systemic amyloidosis has dramatically evolved over the last few years in both AL and ATTR, improving disease prognosis. Moreover, recent studies revealed that timely treatment can lead to an improvement in clinical status and in a regression of amyloid myocardial infiltration showed by imaging, especially by cardiac magnetic resonance, in both AL and ATTR. However, treating cardiac amyloidosis is a complex task due to the frequent association between systemic congestion and low blood pressure, thrombo-embolic and haemorrhagic risk balance, patient frailty, and generally poor prognosis. The aim of this review is to describe the current state of knowledge regarding cardiac amyloidosis therapy in this constantly evolving field, classified as treatment of the cardiac complications of amyloidosis (heart failure, rhythm and conduction disturbances, and thrombo-embolic risk) and the disease-modifying therapy.

Implantable cardioverter-defibrillators in elderly patients: outcome and predictors of mortality

PURPOSE

The implantable cardioverter-defibrillator (ICD) is the therapy of choice for the prevention of sudden cardiac death. The number of elderly patients receiving ICDs is increasing. This study aimed to assess the outcome of patients according to their age at the time of implantation, and to identify variables potentially associated with patient survival.

METHODS

Between June 2009 and December 2019, we retrospectively enrolled all consecutive patients in whom ICD implantation had been performed for primary or secondary prevention at our center.

RESULTS

During the study period, 670 patients underwent ICD implantation. We stratified the population into four age-classes: Class 1 (23%) (pts aged less than 60 years), Class 2 (28%) (pts aged between 60 and 70 years), Class 3 (39%) (pts aged between 70 and 80 years) and Class 4 (9%) (pts aged 80 years or older). Over a median follow-up of 42 months, the rate of deaths in Class 4 was higher than in Classes 1 and 2 (log-rank test, P < 0.01), but was comparable to that in Class 3 (P = 0.407). With increasing age, we observed more complications at the time of implantation and during follow-up. On multivariate analysis, higher NYHA class, creatinine level and CHA₂DS₂-VASc score were identified as independent predictors of death, while age was not associated with worse prognosis. Higher body mass index, higher NYHA class and CHA₂DS₂-VASc score were also confirmed as independent predictors of hospitalizations or death due to any cause.

CONCLUSION

This study showed good survival in ICD patients in all age-groups, including those aged ≥80 years. The CHA₂DS₂-VASc score seems to be a stronger predictor of death than age.

One-Year Outcome After Percutaneous Coronary Intervention for Acute Coronary Syndrome - An Analysis of 20,042 Patients From a Japanese Nationwide Registry

BACKGROUND

Acute coronary syndrome (ACS) hospital survivors experience a wide array of late adverse cardiac events, despite considerable advances in the quality of care. We investigated 30-day and 1-year outcomes of ACS hospital survivors using a Japanese nationwide cohort.Methods and Results:We studied 20,042 ACS patients who underwent percutaneous coronary intervention (PCI) in 2017: 10,242 (51%) with ST-elevation myocardial infarction (STEMI), 3,027 (15%) with non-ST-elevation myocardial infarction (NSTEMI), and 6,773 (34%) with unstable angina (UA). The mean (±SD) age was 69.6±12.4 years, 77% of the patients were men, and 20% had a previous history of PCI. The overall 30-day all-cause, cardiac, and non-cardiac mortality rates were 3.0%, 2.4%, and 0.6%, respectively. The overall 1-year incidence of all-cause, cardiac, and non-cardiac death was 7.1%, 4.2%, and 2.8%, respectively. Compared with UA patients, STEMI patients had a higher risk of all fatal events, non-fatal ischemic stroke, and acute heart failure, and NSTEMI patients had a higher risk of heart failure.

CONCLUSIONS

The results from our ACS hospital survivor PCI database suggest the need to improve care for the acute myocardial infarction population to lessen the burden of 30-day mortality due to ACS, heart failure, and sudden cardiac death, as well as 1-year ischemic stroke and heart failure events.

State-of-the-art narrative review: multimodality imaging in electrophysiology and cardiac device therapies

Cardiac electrophysiology procedures have evolved to provide improvement in morbidity and mortality for many patients. Cardiac resynchronization therapy (CRT), implantable cardioverter/defibrillator (ICD) placement and lead extraction procedures are proven procedures, associated with significant reductions in patient morbidity and mortality as well as improved quality of life. The applications and optimization of these therapies are an evolving field. The optimal use and outcomes of cardiac electrophysiology procedures require a multidisciplinary approach to patient selection, device selection, and procedural planning. Cardiac imaging using echocardiography plays a key role in selection of patients for CRT therapy, for guidance of left ventricular (LV) lead placement, and for optimization of atrioventricular pacing delays in patients with CRT. Cardiac computed tomography (CT) is an important tool in assessment of lead perforation, as well as assessing risk of lead extraction and procedural planning. Cardiac magnetic resonance imaging (MRI) is an important adjunct to transthoracic echocardiography for patient selection and risk stratification for defibrillator therapy for multiple disease states including ischemic cardiomyopathy, hypertrophic cardiomyopathy, cardiac sarcoidosis, and arrhythmogenic right ventricular cardiomyopathy (ARVC). Cardiac positron emission tomography (PET) is a useful adjunct to the diagnosis of device infections as well as inflammatory conditions including cardiac sarcoidosis. Our review attempts to summarize the contemporary roles of multimodality imaging in CRT therapy, ICD therapy and lead extraction therapy.

Postimplantation pocket hematoma increases risk of cardiac implantable electronic device infection: A meta-analysis

INTRODUCTION

 Several studies have shown an inconsistent relationship between postimplantation pocket hematoma and cardiac implantable electronic device (CIED) infection. In this study, we performed a systematic review and meta-analysis to explore the effect of postimplantation hematoma and the risk of CIED infection.

METHODS

 We searched the databases of MEDLINE and EMBASE from inception to March 2020. Included studies were cohort studies, case-control studies, cross-sectional studies, and randomized controlled trials that reported incidence of postimplantation pocket hematoma and CIED infection during the follow-up period. CIED infection was defined as either a device-related local or systemic infection. Data from each study were combined using the random effects, generic inverse variance method of Der Simonian and Laird to calculate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Fourteen studies were included in final analysis, involving a total of 28 319 participants. In random-effect model, we found that postimplantation pocket hematoma significantly increases the risk of overall CIED infection (OR = 6.30, 95% CI: 3.87-10.24, I 2 = 49.3%). There was no publication bias observed in the funnel plot as well as no small-study effect observed in Egger's test.

CONCLUSIONS

Our meta-analysis demonstrated that postimplantation pocket hematoma significantly increases the risk of CIED infection. Precaution should be taken during device implantation to reduce postimplantation hematoma and subsequent CIED infection.

Out of Hospital Sudden Death in a Rural Population: Low Rates of ICD Underutilization Among Decedents

BACKGROUND

Implantable cardioverter defibrillators (ICDs) reduce mortality in patients at risk for life-threatening arrhythmias. Implantation of ICDs in rural or economically disadvantaged populations is suspected to be low. This study examined Out of Hospital Premature Natural Death (OHPND) and electronic medical record (EMR) data to identify rates of non-implantation of ICDs among decedents in eastern North Carolina.

METHODS

OHPND cases in 2016 were identified using mortality data and matched with EMRs. Those meeting criteria for ICD implantation based on chart review were adjudicated by two electrophysiologists to determine whether they qualified for implantation. Comorbidity burden was established using Charlson's Comorbidity Index (CCI).

RESULTS

Out of 1316 OHPND cases, 967 (73.4%) had EMR records. Chart review identified 70 (7.2%) potential ICD candidates with a LVEF ≤35 of which 5 (7.1%) did not meet criteria because LVEF subsequently improved. Of the remaining 65 patients, 32 (49.2%) already received an ICD, and 33 patients (50.7%) met criteria but had not received one. Reasons for non-implantation included: limited life expectancy secondary to comorbidities, principally chronic kidney disease (CKD) (N = 11, 17%), physician non-adherence to guidelines (N = 9, 14%), loss to follow-up (N = 7, 11%), patient refusal (N = 5, 8%), and death before commencing medical therapy (N = 1, 2%). Among our cohort of 967 individuals who died unexpectedly, nine (0.9%) patients may have avoided death with an ICD.

CONCLUSION

This study using decedent data shows low rates of ICD-underutilization in a rural population and emphasizes the role of advanced comorbidities such as CKD in ICD-underutilization.

Testing a nurse-led, pre-implantation educational intervention for primary prevention implantable cardioverter-defibrillator candidates: a randomized feasibility trial

AIMS

Implantable cardioverter-defibrillators (ICDs) deliver therapy for life-threatening arrhythmias. Evidence suggests that ICD candidates have misconceptions regarding ICD therapy and unmet information needs. We undertook a pilot feasibility trial comparing a nurse-led educational intervention plus standard care, vs. standard pre-ICD implantation care. Secondary aims included examination of anxiety, quality of life, and shock anxiety.

METHODS AND RESULTS

Implantable cardioverter-defibrillator candidates were consented and randomized to standard pre-ICD implantation care vs. standard care plus a nurse-led educational intervention. The primary feasibility outcomes included: recruitment rate, consent rate, randomization rate, proportion of participants able to complete all questionnaires, time to deliver intervention, and intervention topics completion. At baseline, demographic and Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety scores were collected. Four weeks post-ICD implantation, participants completed the PROMIS, Florida Patient Acceptance Survey (FPAS), and Florida Shock Anxiety Scale (FSAS). Twenty patients consented (10 per group). Feasibility targets were achieved for all but two outcomes: consent rate was 87% vs. 95% target, and completion of data collection measures was 85% vs. 90% target. Consent rate was lower than expected as one patient declined, and two could not be approached. Completion rate was lower than expected as two patients were lost to follow-up, and one did not receive an ICD during the study period, leading to incomplete post-implantation survey collections.

CONCLUSION

The results demonstrate the feasibility of conducting a trial comparing a nurse-led pre-implantation educational intervention to standard care in an outpatient setting. Further study to evaluate the effectiveness of this intervention on patient-reported outcomes is warranted.

Long-term prognostic value of myocardin expression levels in non-ischemic dilated cardiomyopathy

The mortality of patients with non-ischemic dilated cardiomyopathy (NIDCM) remains substantial. We evaluated gene expression levels of myocardin, an early cardiac gene, in the peripheral blood cells of NIDCM patients as a prognostic biomarker in their long-term outcome and mortality from congestive HF (CHF). We retrospectively analyzed 101 consecutives optimally treated NIDCM patients of Cretan origin who were enrolled from the HF clinic of our hospital from November 2005 to December 2008. Our patient data were either taken from their medical files or recorded during visits to the HF unit or hospitalizations. Follow-up was carried out by telephone interview and by accessing information from general practitioners and cardiologists in private practice. The median follow-up period was 8 years (mean follow-up 7 ± 3.4 years). The overall mortality during follow-up was 61.4%, while mortality due to congestive heart failure (CHF) was 49.5%. Higher CHF and all-cause mortality were observed in patients with myocardin levels < 14.26 (p < 0.001 for both CHF and all-cause mortality). A multivariate Cox regression analysis showed that myocardin level of expression had independent significant prognostic value for the risk of death from CHF (HR 14.5, 95% confidence interval (CI) 5.3-39) in those patients. Peripheral blood cells gene expression of myocardin, an early myocardial marker, may serve as prognostic biomarkers of the long-term outcome of patients with NIDCM. Our findings open new prospects in the risk stratification of these patients.

Better Than You Think—Appropriate Use of Implantable Cardioverter-Defibrillators at a Single Academic Center: A Retrospective Review

Background: Implantable cardioverter-defibrillators (ICDs) can be life-saving devices, although they are expensive and may cause complications. In 2013, several professional societies published joint appropriate use criteria (AUC) assessing indications for ICD implantation. Data evaluating the clinical application of AUC are limited. Previous registry-based studies estimated that 22.5% of primary prevention ICD implantations were “non-evidence-based” implantations. On the basis of AUC, we aimed to determine the prevalence of “rarely appropriate” ICD implantation at our institution for comparison with previous estimates.Methods: We reviewed 286 patients who underwent ICD implantation between 2013 and 2016. Appropriateness of each ICD implantation was assessed by independent review and rated on the basis of AUC.Results: Of 286 ICD implantations, two independent reviewers found that 89.5% and 89.2%, respectively, were appropriate, 5.6% and 7.3% may be appropriate, and 1.8% and 2.1% were rarely appropriate. No AUC indication was found for 3.5% and 3.4% of ICD implantations, respectively. Secondary prevention ICD implantations were more likely rarely appropriate (2.6% vs. 1.2% and 3.6% vs. 1.1%) or unrated (6.0% vs. 1.2% and 2.7% vs. 0.6%). The reviewers found 3.5% and 3.4% of ICD implantations, respectively, were non-evidence-based implantations. The difference in rates between reviewers was not statistically significant.Conclusion: Compared with prior reports, our prevalence of rarely appropriate ICD implantation was very low. The high appropriate use rate could be explained by the fact that AUC are based on current clinical practice. The AUC could benefit from additional secondary prevention indications. Most importantly, clinical judgement and individualized care should determine which patients receive ICDs irrespective of guidelines or criteria.

Hyperthyroidism precipitating cardiac arrest in a patient with Brugada pattern

A 38-year-old man previously healthy suffered an out-of-hospital cardiac arrest; he was resuscitated successfully and admitted to the intensive care unit. His initial ECG suggested a Brugada pattern; other laboratory tests revealed low potassium level, low Thyroid Stimulating Hormone (TSH) and high FT4. He was started on carbimazole for hyperthyroidism, along with other supportive care. A comprehensive cardiac evaluation was done, including ajmaline and flecainide tests, results were inconclusive. An implantable cardioverter defibrillator device (ICD) was inserted to prevent such catastrophic events in the future. After discharge and on follow-up, our patient was doing well. His thyroid function test (TFT) was normal; moreover, a follow-up ICD interrogation did not record any arrhythmias. This case report highlighted asymptomatic hyperthyroidism as a precipitant for Brugada pattern resulting in sudden cardiac arrest.

Global and regional cardiac dysfunction quantified by 18F-FDG PET scans can predict ventricular arrhythmia in patients with implantable cardioverter defibrillator

BACKGROUND

A low appropriate therapy rate indicates that a minority of patients will benefit from their implantable cardioverter defibrillator (ICD). Quantitative measurements from 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) may predict ventricular arrhythmia (VA) occurrence after ICD placement.

METHODS

We performed a prospective observational study and recruited patients who required ICD placement. Pre-procedure image scans were performed. Patients were followed up for VA occurrence. Associations between image results and VA were analyzed.

RESULTS

In 51 patients (33 males, 53.9 ± 17.2 years) analyzed, 17 (33.3%) developed VA. Compared with patients without VA, patients with VA had significantly larger values in scar area (17.7 ± 12.4% vs. 7.0 ± 7.9%), phase standard deviation (51.4° ± 14.0° vs. 34.0° ± 15.0°), bandwidth (172.9° ± 39.8° vs. 128.7° ± 49.9°), sum thickening score (STS, 29.5 ± 11.1 vs. 17.8 ± 13.2), and sum motion score (42.9 ± 11.5 vs. 33.0 ± 19.0). Cox regression analysis and receiver operating characteristic curve analysis showed that scar size, dyssynchrony, and STS were associated with VA occurrence (HR, 4.956, 95% CI 1.70-14.46).

CONCLUSION

Larger left ventricular scar burden, increased dyssynchrony, and higher STS quantified by 18F-FDG PET may indicate a higher VA incidence after ICD placement.

Presence of contractile impairment appears crucial for structural remodeling in idiopathic left bundle-branch block

BACKGROUND

To differentiate effects of ventricular asynchrony from an underlying hypocontractile cardiomyopathy this study aimed to enhance the understanding of functional impairment and structural remodeling in idiopathic left bundle-branch block (LBBB). We hypothesize, that functional asynchrony with septal flash volume effects alone might not entirely explain the degree of functional impairment. Hence, we suggest the presence of a superimposed contractile cardiomyopathy.

METHODS

In this retrospective study, 53 patients with idiopathic LBBB were identified and matched to controls with and without cardiovascular risk factors. Cardiovascular magnetic resonance (CMR) was used to evaluate cardiac function, volumes and myocardial fibrosis using native T1 mapping and late gadolinium enhancement (LGE). Septal flash volume was assessed by CMR volumetric measurements and allowed to stratify patients with systolic dysfunction solely due to isolated ventricular asynchrony or superimposed contractile impairment.

RESULTS

Reduced systolic LV-function, increased LV-volumes and septal myocardial fibrosis were found in patients with idiopathic LBBB compared to healthy controls. LV-volumes increased and systolic LV-function declined with prolonged QRS duration. Fibrosis was typically located at the right ventricular insertion points. Subgroups with superimposed contractile impairment appeared with pronounced LV dilation and increased fibrotic remodeling compared to individuals with isolated ventricular asynchrony.

CONCLUSIONS

The presence of superimposed contractile impairment in idiopathic LBBB is crucial to identify patients with enhanced structural remodeling. This finding suggests an underlying cardiomyopathy. Future studies are needed to assess a possible prognostic impact of this entity and the development of heart failure.

TRIAL REGISTRATION

This study was retrospectively registered.

Cost-impact analysis of baroreflex activation therapy in chronic heart failure patients in the United States

Background

The study evaluated the cost of baroreflex activation therapy plus guideline directed therapy (BAT + GDT) compared to GDT alone for HF patients with reduced ejection fraction and New York Heart Association Class III or II (with a recent history of III). Baroreflex activation therapy (BAT) is delivered by an implantable device that stimulates the baroreceptors through an electrode attached to the outside of the carotid artery, which rebalances the autonomic nervous system to regain cardiovascular (CV) homeostasis. The BeAT-HF trial evaluated the safety and effectiveness of BAT.

Methods

A cost impact model was developed from a U.S. health care payer or integrated delivery network perspective over a 3-year period for BAT + GDT versus GDT alone. Expected costs were calculated by utilizing 6-month data from the BeAT-HF trial and existing literature. HF hospitalization rates were extrapolated based on improvement in NT-proBNP.

Results

At baseline the expected cost of BAT + GDT were $29,526 per patient more than GDT alone due to BAT device and implantation costs. After 3 years, the predicted cost per patient was $9521 less expensive for BAT + GDT versus GDT alone due to lower rates of significant HF hospitalizations, CV non-HF hospitalizations, and resource intensive late-stage procedures (LVADs and heart transplants) among the BAT + GDT group.

Conclusions

BAT + GDT treatment becomes less costly than GDT alone beginning between years 1 and 2 and becomes less costly cumulatively between years 2 and 3, potentially providing significant savings over time. As additional BeAT-HF trial data become available, the model can be updated to show longer term effects.

Advanced Therapies for Ventricular Arrhythmias in Patients With Chagasic Cardiomyopathy: JACC State-of-the-Art Review

Chagas disease is caused by infection from the protozoan parasite Trypanosoma cruzi. Although it is endemic to Latin America, global migration has led to an increased incidence of Chagas in Europe, Asia, Australia, and North America. Following acute infection, up to 30% of patients will develop chronic Chagas disease, with most patients developing Chagasic cardiomyopathy. Chronic Chagas cardiomyopathy is highly arrhythmogenic, with estimated annual rates of appropriate implantable cardioverter-defibrillator therapies and electrical storm of 25% and 9.1%, respectively. Managing arrhythmias in patients with Chagasic cardiomyopathy is a major challenge for the clinical electrophysiologist, requiring intimate knowledge of cardiac anatomy, advanced training, and expertise. Endocardial-epicardial mapping and ablation strategy is needed to treat arrhythmias in this patient population, owing to the suboptimal long-term success rate of endocardial mapping and ablation alone. We also describe innovative approaches to improve acute and long-term clinical outcomes in patients with refractory ventricular arrhythmias following catheter ablation, such as bilateral cervicothoracic sympathectomy and bilateral renal denervation, among others.

Heart Failure With Recovered Left Ventricular Ejection Fraction: JACC Scientific Expert Panel

Reverse left ventricular (LV) remodeling and recovery of LV function are associated with improved clinical outcomes in patients with heart failure with reduced ejection fraction. A growing body of evidence suggests that even among patients who experience a complete normalization of LV ejection fraction, a significant proportion will develop recurrent LV dysfunction accompanied by recurrent heart failure events. This has led to intense interest in understanding how to manage patients with heart failure with recovered ejection fraction (HFrecEF). Because of the lack of a standard definition for HFrecEF, and the paucity of clinical data with respect to the natural history of HFrecEF patients, there are no current guidelines on how these patients should be followed up and managed. Accordingly, this JACC Scientific Expert Panel reviews the biology of reverse LV remodeling and the clinical course of patients with HFrecEF, as well as provides guidelines for defining, diagnosing, and managing patients with HFrecEF.

Diagnosis and treatment of cardiac amyloidosis: position statement of the German Cardiac Society (DGK)

Systemic forms of amyloidosis affecting the heart are mostly light-chain (AL) and transthyretin (ATTR) amyloidoses. The latter is caused by deposition of misfolded transthyretin, either in wild-type (ATTRwt) or mutant (ATTRv) conformation. For diagnostics, specific serum biomarkers and modern non-invasive imaging techniques, such as cardiovascular magnetic resonance imaging (CMR) and scintigraphic methods, are available today. These imaging techniques do not only complement conventional echocardiography, but also allow for accurate assessment of the extent of cardiac involvement, in addition to diagnosing cardiac amyloidosis. Endomyocardial biopsy still plays a major role in the histopathological diagnosis and subtyping of cardiac amyloidosis. The main objective of the diagnostic algorithm outlined in this position statement is to detect cardiac amyloidosis as reliably and early as possible, to accurately determine its extent, and to reliably identify the underlying subtype of amyloidosis, thereby enabling subsequent targeted treatment.

Prognosis of Japanese Patients With Coronary Artery Disease Who Underwent Implantable Cardioverter Defibrillator Implantation - The JID-CAD Study

Background: There has been no large multicenter clinical trial on the prognosis of implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D) in Japanese patients with coronary artery disease (CAD). The aim of the present study was to compare differences in the prognoses of Japanese patients with CAD between primary and secondary prevention, and to identify potential predictors of prognosis.

Methods and Results: We investigated 392 CAD patients (median age 69 years, 90% male) treated with ICD/CRT-D enrolled in the Japan Implantable Devices in CAD (JID-CAD) Registry. The primary endpoint was all-cause death, and the secondary endpoint was appropriate ICD therapies. Endpoints were assessed by dividing patients into primary prevention (n=165) and secondary prevention (n=227) groups. The mean (±SD) follow-up period was 2.1±0.9 years. The primary endpoint was similar in the 2 groups (P=0.350).

Conclusions: The mortality rate in Japanese patients with CAD who underwent ICD/CRT-D implantation as primary prevention was not lower than that of patients who underwent ICD/CRT-D implantation as secondary prevention, despite the lower cardiac function in the patients undergoing ICD/CRT-D implantation as primary prevention.

Cine and late gadolinium enhancement MRI registration and automated myocardial infarct heterogeneity quantification

PURPOSE

To develop an approach for automated quantification of myocardial infarct heterogeneity in late gadolinium enhancement (LGE) cardiac MRI.

METHODS

We acquired 2D short-axis cine and 3D LGE in 10 pigs with myocardial infarct. The 2D cine myocardium was segmented and registered to the LGE images. LGE image signal intensities within the warped cine myocardium masks were analyzed to determine the thresholds of infarct core (IC) and gray zone (GZ) for the standard-deviation (SD) and full-width-at-halfmaximum (FWHM) methods. The initial IC, GZ, and IC + GZ segmentations were postprocessed using a normalized cut approach. Cine segmentation and cine-LGE registration accuracies were evaluated using dice similarity coefficient and average symmetric surface distance. Automated IC, GZ, and IC + GZ volumes were compared with manual results using Pearson correlation coefficient (r), Bland-Altman analyses, and intraclass correlation coefficient.

RESULTS

For n = 87 slices containing scar, we achieved cine segmentation dice similarity coefficient = 0.87 ± 0.12, average symmetric surface distance = 0.94 ± 0.74 mm (epicardium), and 1.03 ± 0.82 mm (endocardium) in the scar region. For cine-LGE registration, dice similarity coefficient was 0.90 ± 0.06 and average symmetric surface distance was 0.72 ± 0.39 mm (epicardium) and 0.86 ± 0.53 mm (endocardium) in the scar region. For both SD and FWHM methods, automated IC, GZ, and IC + GZ volumes were strongly (r > 0.70) correlated with manual measurements, and the correlations were not significantly different from interobserver correlations (P > .05). The agreement between automated and manual scar volumes (intraclass correlation coefficient = 0.85-0.96) was similar to that between two observers (intraclass correlation coefficient = 0.81-0.99); automated scar segmentation errors were not significantly different from interobserver segmentation differences (P > .05).

CONCLUSIONS

Our approach provides fully automated cine-LGE MRI registration and LGE myocardial infarct heterogeneity quantification in preclinical studies.

Incremental prognostic value of myocardial neuroadrenergic damage in patients with chronic congestive heart failure: An iodine-123 meta-iodobenzylguanidine scintigraphy study

BACKGROUND

ICD in primary prevention reduced mortality in patients with heart failure (HF); however, in about 80% of the ICD recipients an event requiring a device intervention will never occur. Thus, a reliable screening test included in a multiparametric approach to appropriately select patients to ICD implantation is increasingly required. Aim of the work was to assess if the Iodine-123 Meta-Iodobenzylguanidine scintigraphy (123I-mIBG) could be useful to identify patients with HF who would not benefit from the ICD implantation because at low risk of arrhythmias.

METHODS AND RESULTS

This is a retrospective multicentre study on patients undergoing 123I-mIBG from February 2012 to December 2015. Inclusion criteria where: age ≥ 18 years old, LVEF ≤ 35% with idiopathic or ischemic heart disease, no previous malignant ventricular arrhythmias. Patients were divided in two groups based on of late H/M < or ≥ 1.60 on 123I-mIBG. Primary end-point was occurrence of malignant arrhythmias. Secondary end-point was occurrence of cardiac death and hospitalization for worsening HF. MACE were mortality and malignant arrhythmias. Eighty-one patients were enrolled (mean age: 69 years). On 123I-mIBG, 54 patients had late H/M < 1.6 and 27 patients had late H/M ≥ 1.60. After a mean follow-up of 13.3 (± 9.7) months, the primary end-point occurred in 13 patients out of 81. No arrhythmias occurred in patients with H/M late ≥ 1.6. Nineteen patients out of 20 with MACE showed an H/M late < 1.6. Death in group with H/M ≥ 1.6 occurred for worsening HF. A late H/M ≥ 1.60 showed a very high NPV for arrhythmia (100%) and for death (96.3%).

CONCLUSION

123I-mIBG imaging has the capability to identify patients at low risk of events.

Fully automated quantification of left ventricular volumes and function in cardiac MRI: clinical evaluation of a deep learning-based algorithm

To investigate the performance of a deep learning-based algorithm for fully automated quantification of left ventricular (LV) volumes and function in cardiac MRI. We retrospectively analysed MR examinations of 50 patients (74% men, median age 57 years). The most common indications were known or suspected ischemic heart disease, cardiomyopathies or myocarditis. Fully automated analysis of LV volumes and function was performed using a deep learning-based algorithm. The analysis was subsequently corrected by a senior cardiovascular radiologist. Manual volumetric analysis was performed by two radiology trainees. Volumetric results were compared using Bland–Altman statistics and intra-class correlation coefficient. The frequency of clinically relevant differences was analysed using re-classification rates. The fully automated volumetric analysis was completed in a median of 8 s. With expert review and corrections, the analysis required a median of 110 s. Median time required for manual analysis was 3.5 min for a cardiovascular imaging fellow and 9 min for a radiology resident (p < 0.0001 for all comparisons). The correlation between fully automated results and expert-corrected results was very strong with intra-class correlation coefficients of 0.998 for end-diastolic volume, 0.997 for end-systolic volume, 0.899 for stroke volume, 0.972 for ejection fraction and 0.991 for myocardial mass (all p < 0.001). Clinically meaningful differences between fully automated and expert corrected results occurred in 18% of cases, comparable to the rate between the two manual readers (20%). Deep learning-based fully automated analysis of LV volumes and function is feasible, time-efficient and highly accurate. Clinically relevant corrections are required in a minority of cases.

T1 Mapping Tissue Heterogeneity Provides Improved Risk Stratification for ICDs Without Needing Gadolinium in Patients With Dilated Cardiomyopathy

OBJECTIVES

This study sought to determine whether myocardial tissue heterogeneity scanned by native T₁ mapping could improve risk stratification in patients with nonischemic dilated cardiomyopathy (NICM) evaluated for primary prevention by ICD.

BACKGROUND

The benefit of insertable cardiac-defibrillator (ICD) as primary prevention ICD in patients with NICM remains to be fully clarified.

METHODS

A total of 115 NICM candidates for primary prevention and 55 healthy controls with similar distributions of age and sex were prospectively enrolled. Imaging was performed at 1.5-T using a protocol that included cine magnetic resonance for left ventricular function, late gadolinium enhancement (LGE) for focal scarring, and 5-slice native T₁ mapping for diffuse fibrosis and heterogeneity. The last method was assessed by mean absolute deviation of the segmental pixel-SD from the average pixel-SD (Mad-SD). The primary endpoint was a composite of appropriate ICD therapy and sudden cardiac death.

RESULTS

During a median follow-up of 24 months, 13 patients (11%) experienced the primary endpoint. Dichotomized Mad-SD >0.24 provided a comparable outcome to the presence of LGE for the primary endpoint (annual event rate: 9.8% vs. 10.9%). The integration of Mad-SD to global native T₁ showed excellent arrhythmic event-free survival (annual event rate: 0%), and high sensitivity of 85% (95% confidence interval [CI]: 55% to 98%) and moderate specificity of 72% (95% CI: 62% to 80%), with a C-statistic of 0.76 (95% CI: 0.64 to 0.87), which was comparable to the presence, location, or extent of LGE in its ability to predict arrhythmic events.

CONCLUSIONS

Combined myocardium tissue heterogeneity and interstitial fibrosis assessment by native T₁ mapping is an important predictor of ventricular tachycardia and ventricular fibrillation and provides additive risk stratification for primary prevention ICD in NICM patients without the need for gadolinium contrast.

Idiopathic Ventricular Fibrillation: Diagnosis, Ablation of Triggers, Gaps in Knowledge, and Future Directions

Idiopathic ventricular fibrillation (IVF) is a diagnosis of exclusion made when no underlying cause is identified in a cardiac arrest survivor. Although the frequency of this diagnosis has declined over time due to advances in diagnostic techniques, it remains a substantial cause of sudden cardiac arrest. Further, IVF tends to recur. This article reviews the criteria for diagnosis, patient characteristics, the two primary arrhythmic phenotypes—short-coupled variant of torsades de pointes and recurrent paroxysmal IVF—and the electrophysiologic features, treatment, and ablation of premature ventricular complexes that can trigger IVF.

Clinical characteristics and long-term prognosis of ischemic and non-ischemic cardiomyopathy

Objectives

The different etiology of HF has different prognostic risk factors. Prognosis assessment of ICM and NICM has important clinical value. This study is aimed to explore the predicting factors for ICM and NICM.

Methods

1082 HFrEF patients were retrospectively enrolled from Jan. 01, 2016 to Dec. 31, 2017. On Jan. 31, 2019, 873 patients were enrolled for analysis excluding incomplete, unfollowed, and unexplained data. The patients were divided into ischemic and non-ischemic group. The differences in clinical characteristics and long-term prognosis between the two groups were analyzed, and multivariate Cox analysis was used to predict the respective all-cause mortality, SCD and rehospitalization of CHF.

Results

873 patients aged 64(53,73) were divided into two groups: ICM (403, 46.16%) and NICM. At the end, 203 died (111 in ICM, 54.68%), of whom 87 had SCD (53 in ICM, 60.92%) and 269 had rehospitalization for HF(134 in ICM, 49.81%). Independent risk factors affecting all-cause mortality in ICM: DM, previous hospitalization of HF, age, eGFR, LVEF; for SCD: PVB, eGFR, Hb, revascularization; for readmission of HF: low T3 syndrome, PVB, DM, previous hospitalization of HF, eGFR. Otherwise; factors affecting all-cause mortality in NICM: NYHA III-IV, paroxysmal AF/AFL, previous hospitalization of HF, β-blocker; for SCD: low T3 syndrome, PVB, nitrates, sodium, β-blocker; for rehospitalization of HF: paroxysmal AF/AFL, previous admission of HF, LVEF.

Conclusions

Both all-cause mortality and SCD in ICM is higher than that in NICM. Different etiologies of CHF have different risk factors affecting the prognosis.

Implantable Cardioverter Defibrillators and Chronic Kidney Disease

Use of implantable cardioverter defibrillators (ICDs) is the treatment of choice for heart failure patients with ejection fraction <35% to prevent sudden cardiac death. Whether this benefit remains among patients with chronic kidney disease (CKD) or end stage renal disease (ESRD) is yet to be elucidated. We conducted a systematic review of studies in PubMed that have investigated the use of ICDs among patients with CKD or ESRD. From the 470 studies identified, we selected 42 for the current review. Patients with CKD/ESRD were more likely to get antitachycardia pacing or shocks and had higher cardiac and/or all-cause mortality compared to patients without CKD/ESRD. These associations had an inverse dose-response effect with worse outcomes with decreasing kidney function. In conclusion, use of ICDs in CKD/ESRD is associated with increased antitachycardia pacing/shocks and mortality suggesting that their routine use in this patient population may be associated with more adverse outcomes than benefits.