Natural history of cardiac involvement in myotonic dystrophy type 1 - Emphasis on the need for lifelong follow-up

BACKGROUND

Cardiac involvement represents a major cause of morbidity and mortality in patients with myotonic dystrophy type 1 (DM1) and prevention of sudden cardiac death (SCD) is a central part of patient care. We investigated the natural history of cardiac involvement in patients with DM1 to provide an evidence-based foundation for adjustment of follow-up protocols.

METHODS

Patients with genetically confirmed DM1 were identified. Data on patient characteristics, performed investigations (12 lead ECG, Holter monitoring and echocardiography), and clinical outcomes were retrospectively collected from electronic health records.

RESULTS

We included 195 patients (52% men) with a mean age at baseline evaluation of 41 years (range 14-79). The overall prevalence of cardiac involvement increased from 42% to 66% after a median follow-up of 10.5 years. There was a male predominance for cardiac involvement at end of follow-up (74 vs. 44%, p < 0.001). The most common types of cardiac involvement were conduction abnormalities (48%), arrhythmias (35%), and left ventricular systolic dysfunction (21%). Only 17% of patients reported cardiac symptoms. The standard 12‑lead ECG was the most sensitive diagnostic modality and documented cardiac involvement in 24% at baseline and in 49% at latest follow-up. However, addition of Holter monitoring and echocardiography significantly increased the diagnostic yield with 18 and 13% points at baseline and latest follow-up, respectively. Despite surveillance 35 patients (18%) died during follow-up; seven due to SCD.

CONCLUSIONS

In patients with DM1 cardiac involvement was highly prevalent and developed during follow-up. These findings justify lifelong follow-up with ECG, Holter, and echocardiography.

CLINICAL PERSPECTIVE

What is new? What are the clinical implications?

Computed tomography or chest X-ray to assess pulmonary congestion in dyspnoeic patients with acute heart failure

AIMS

While computed tomography (CT) is widely acknowledged as superior to chest radiographs for acute diagnostics, its efficacy in diagnosing acute heart failure (AHF) remains unexplored. This prospective study included consecutive patients with dyspnoea undergoing simultaneous low-dose chest CT (LDCT) and chest radiographs. Here, we aimed to determine if LDCT is superior to chest radiographs to confirm pulmonary congestion in dyspnoeic patients with suspected AHF.

METHODS AND RESULTS

An observational, prospective study, including dyspnoeic patients from the emergency department. All patients underwent concurrent clinical examination, laboratory tests, echocardiogram, chest radiographs, and LDCT. The primary efficacy measure to compare the two radiological methods was conditional odds ratio (cOR). The primary outcome was adjudicated AHF, ascertained by comprehensive expert consensus. The secondary outcome, echo-bnp AHF, was an objective AHF diagnosis based on echocardiographic cardiac dysfunction, elevated cardiac filling pressure, loop diuretic administration, and NT-pro brain natriuretic peptide > 300 pg/mL. Of 228 dyspnoeic patients, 64 patients (28%) had adjudicated AHF, and 79 patients (35%) had echo-bnp AHF. Patients with AHF were older (78 years vs. 73 years), had lower left ventricular ejection fraction (36% vs. 55%), had higher elevated left ventricular filling pressures (98% vs. 18%), and had higher NT-pro brain natriuretic peptide levels (3628 pg/mL vs. 470 pg/mL). The odds to diagnose adjudicated AHF and echo-bnp AHF were up to four times greater using LDCT (cOR: 3.89 [2.15, 7.06] and cOR: 2.52 [1.45, 4.38], respectively). For each radiologic sign of pulmonary congestion, the LDCT provided superior or equivalent results as the chest radiographs, and the interrater agreement was higher using LDCT (kappa 0.88 [95% CI: 0.81, 0.95] vs. 0.73 [95% CI: 0.63, 0.82]). As first-line imaging modality, LDCT will find one additional adjudicated AHF in 12.5 patients and prevent one false-positive in 20 patients. Similar results were demonstrated for echo-bnp AHF.

CONCLUSIONS

In consecutive dyspnoeic patients admitted to the emergency department, LDCT is significantly better than chest radiographs in detecting pulmonary congestion.

Association between QRS shortening and mortality after cardiac resynchronization therapy: Results from the DANISH study

BACKGROUND

Changes in QRS duration (∆QRS) are often used in the clinical setting to evaluate the effect of cardiac resynchronization therapy (CRT), although an association between ∆QRS and outcomes is not firmly established. We aimed to assess the association between mortality and ∆QRS after CRT in patients from the DANISH (Danish Study to Assess the Efficacy of ICDs in Patients with Non-Ischemic Systolic Heart Failure on Mortality) study.

METHODS

We included all patients from DANISH who received a CRT device and had available QRS duration data before and after implantation. Cox proportional hazards models were used to assess associations between ∆QRS (post-CRT QRS minus pre-CRT QRS) and mortality.

RESULTS

Complete data were available in 572 patients. Median baseline QRS duration was 160 ms (IQR [146;180]). Post-CRT QRS was recorded a median of 48 days (IQR [33;86]) after implantation, and the median ∆QRS was -14 ms (IQR [-38;-3]). During a median follow-up of 4.1 years (IQR [2.5;5.8]), 106 patients died. In crude Cox regression, all-cause mortality was reduced by 6% per 10 ms shortening of QRS (HR 0.94; CI: 0.88-1.00, p = 0.04). The effect did not remain significant after multivariable adjustment (HR 1.01, CI: 0.93-1.10, p = 0.77). Further, no association was found between ∆QRS and improvement of New York Heart Association functional class at 6 months (OR 1.03, CI: 0.96-1.10, p = 0.42).

CONCLUSION

In a large cohort of patients with non-ischemic cardiomyopathy, reduction of QRS duration after CRT was not associated with changes in mortality during long-term follow-up.

Estimated Glomerular Filtration Rate and Implantable Cardioverter-Defibrillator in Nonischemic Systolic Heart Failure: Extended Follow-Up of DANISH

BACKGROUND

Patients with heart failure and chronic kidney disease (CKD) may have an increased risk of death from causes competing with arrhythmic death, which could have implications for the efficacy of implantable cardioverter-defibrillators (ICDs). We examined the long-term effects of primary prophylactic ICD implantation, compared with usual care, according to baseline CKD status in an extended follow-up study of DANISH (Danish Study to Assess the Efficacy of ICDs in Patients With Nonischemic Systolic Heart Failure on Mortality).

METHODS AND RESULTS

In the DANISH trial, 1116 patients with nonischemic heart failure with reduced ejection fraction were randomized to receive an ICD (N=556) or usual care (N=550). Outcomes were analyzed according to CKD status (estimated glomerular filtration rate ≥/<60 mL/min per 1.73 m2) at baseline. In total, 1113 patients had an available estimated glomerular filtration rate measurement at baseline (median estimated glomerular filtration rate 73 mL/min per 1.73 m2), and 316 (28%) had CKD. During a median follow-up of 9.5 years, ICD implantation, compared with usual care, did not reduce the rate of all-cause mortality (no CKD, HR, 0.82 [95% CI, 0.64-1.04]; CKD, HR, 1.02 [95% CI, 0.75-1.38]; Pinteraction=0.31) or cardiovascular death (no CKD, HR, 0.77 [95% CI, 0.58-1.03]; CKD, HR, 1.05 [95% CI, 0.73-1.51]; Pinteraction=0.20), irrespective of baseline CKD status. Similarly, baseline CKD status did not modify the beneficial effects of ICD implantation on sudden cardiovascular death (no CKD, HR, 0.57 [95% CI, 0.32-1.00]; CKD, HR, 0.65 [95% CI, 0.34-1.24]; Pinteraction=0.70).

CONCLUSIONS

ICD implantation, compared with usual care, did not reduce the overall mortality rate, but it did reduce the rate of sudden cardiovascular death, regardless of baseline kidney function in patients with nonischemic heart failure with reduced ejection fraction.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT00542945.

Thoracentesis to alleviate pleural effusion in acute heart failure: study protocol for the multicentre, open-label, randomised controlled TAP-IT trial

INTRODUCTION

Pleural effusion is present in half of the patients hospitalised with acute heart failure. The condition is treated with diuretics and/or therapeutic thoracentesis for larger effusions. No evidence from randomised trials or guidelines supports thoracentesis to alleviate pleural effusion due to acute heart failure. The Thoracentesis to Alleviate cardiac Pleural effusion Interventional Trial (TAP-IT) will investigate if a strategy of referring patients with acute heart failure and pleural effusion to up-front thoracentesis by pleural pigtail catheter insertion in addition to pharmacological therapy compared with pharmacological therapy alone can increase the number of days the participants are alive and not hospitalised during the 90 days following randomisation.

METHODS AND ANALYSIS

TAP-IT is a pragmatic, multicentre, open-label, randomised controlled trial aiming to include 126 adult patients with left ventricular ejection fraction ≤45% and a non-negligible pleural effusion due to heart failure. Participants will be randomised 1:1, stratified according to site and anticoagulant treatment, and assigned to referral to up-front ultrasound-guided pleural pigtail catheter thoracentesis in addition to standard pharmacological therapy or to standard pharmacological therapy only. Thoracentesis is performed according to local guidelines and can be performed in participants in the pharmacological treatment arm if their condition deteriorates or if no significant improvement is observed within 5 days. The primary endpoint is how many days participants are alive and not hospitalised within 90 days from randomisation and will be analysed in the intention-to-treat population. Key secondary outcomes include 90-day mortality, complications, readmissions, and quality of life.

ETHICS AND DISSEMINATION

The study has been approved by the Capital Region of Denmark Scientific Ethical Committee (H-20060817) and Knowledge Center for Data Reviews (P-2021-149). All participants will sign an informed consent form. Enrolment began in August 2021. Regardless of the nature, results will be published in a peer-reviewed medical journal.

TRIAL REGISTRATION NUMBER

NCT05017753.

The COVID-19 in athletes (COVA) study: a national study on cardio-pulmonary involvement of SARS-CoV-2 infection among elite athletes

Background

COVID-19 can cause cardiopulmonary involvement. Physical activity and cardiac complications can worsen prognosis, while pulmonary complications can reduce performance.

Aims

To determine the prevalence and clinical implications of SARS-CoV-2 cardiopulmonary involvement in elite athletes.

Methods

An observational study between 1 July 2020 and 30 June 2021 with the assessment of coronary biomarkers, electrocardiogram, echocardiography, Holter-monitoring, spirometry, and chest X-ray in Danish elite athletes showed that PCR-tested positive for SARS-CoV-2. The cohort consisted of male football players screened weekly (cohort I) and elite athletes on an international level only tested if they had symptoms, were near-contact, or participated in international competitions (cohort II). All athletes were categorized into two groups based on symptoms and duration of COVID-19: Group 1 had no cardiopulmonary symptoms and duration ≤7 days, and; Group 2 had cardiopulmonary symptoms or disease duration >7 days.

Results

In total 121 athletes who tested positive for SARS-CoV-2 were investigated. Cardiac involvement was identified in 2/121 (2%) and pulmonary involvement in 15/121 (12%) participants. In group 1, 87 (72%), no athletes presented with signs of cardiac involvement, and 8 (7%) were diagnosed with radiological COVID-19-related findings or obstructive lung function. In group 2, 34 (28%), two had myocarditis (6%), and 8 (24%) were diagnosed with radiological COVID-19-related findings or obstructive lung function.

Conclusions

These clinically-driven data show no signs of cardiac involvement among athletes who tested positive for SARS-CoV-2 infection without cardiopulmonary symptoms and duration <7 days. Athletes with cardiopulmonary symptoms or prolonged duration of COVID-19 display, exercise-limiting cardiopulmonary involvement.

Angiotensin receptor blockers in patients with hypertrophic cardiomyopathy: A comparison of VANISH and INHERIT randomized trials

PURPOSE

To identify the cause of discrepancy between the INHERIT trial and VANISH trial in regards to disease modification of angiotensin receptor II blockers in hypertrophic cardiomyopathy (HCM).

METHODS

We replicated the data analysis used in VANISH, converting individual change in each component of the composite endpoint into a z-score and applying this z-score to the INHERIT results.

RESULTS

No significant improvement was identified in the composite z-score between the 2 groups at 12-month follow-up (P = .4). With the exception of tissue Doppler systolic (s') velocity, we found no significant benefit or harm from losartan compared to placebo for any of the individual components of the composite score at 12-month follow-up. Results were similar in analyses without imputed data or when restricted to patients with sarcomeric HCM.

CONCLUSION

Despite applying the potentially more sensitive composite z-score endpoint as in the VANISH trial, no statistically significant benefits from the use of losartan compared to placebo could be detected at 12-month follow-up in patients with overt HCM participating in the INHERIT trial.

Initiation of eplerenone or spironolactone, treatment adherence, and associated outcomes in patients with new-onset heart failure with reduced ejection fraction: a nationwide cohort study

BACKGROUND

The mineralocorticoid receptor antagonists (MRAs) eplerenone and spironolactone are beneficial in heart failure with reduced ejection fraction (HFrEF), but have not been prospectively compared. We compared clinical outcomes, daily dosages, and discontinuation rates for the two drugs in a nationwide cohort.

METHODS

We identified all patients with HFrEF in the period 2016-2020, who were alive and had initiated MRA treatment at study start, 180 days after HF diagnosis. We estimated the 2-year risk of a composite of death and HF hospitalization, as well as each component separately, using Kaplan-Meier, cumulative incidence functions, and Cox proportional hazards models adjusted for age, sex, and comorbidities. Secondly, we assessed treatment withdrawal, cross-over, and daily drug dosage.

RESULTS

We included 7479 patients; 653 (9%) on eplerenone and 6840 (91%) on spironolactone. Patients in the eplerenone group were younger (median age 65 vs. 69 years), and more often men (91% vs. 68%), both P < 0.001. In adjusted analyses, with spironolactone as reference, there were no differences in the risk of the composite of all-cause death and HF hospitalization (HR 1.02, 95% CI 0.82-1.27), all-cause death (HR 0.93, 95% CI 0.67-1.30), or HF hospitalization (HR 1.10, 95% CI 0.84-1.42). Treatment withdrawal occurred in 34% in the eplerenone group and 53% in the spironolactone group (P < 0.001), treatment cross-over in 3%, and 10%, respectively. Daily dose >25 mg at 12 months, was observed in 230 patients (37%) in the eplerenone group and 771 patients (12%) in the spironolactone (P < 0.001).

CONCLUSIONS

In a contemporary nationwide cohort of patients with new-onset HFrEF who initiated MRA, we found no differences in clinical outcomes associated with initiation of eplerenone vs. spironolactone. Treatment was more frequently withdrawn, and daily drug dosage was lower among patients treated with spironolactone.

Right Ventricular Free Wall Strain and Effect of Defibrillator Implantation in Patients With Nonischemic Systolic Heart Failure

BACKGROUND

Patients with nonischemic systolic heart failure have an increased risk of malignant ventricular arrhythmias and sudden cardiovascular death. Because the risk is less pronounced than for patients with ischemic cause of heart failure more discriminating tools are needed to identify patients most likely to benefit from implantable cardioverter-defibrillator (ICD) implantation. Right ventricular (RV) dysfunction is associated with a worse prognosis, but whether RV free wall strain (RV-FWS) measured with echocardiography can identify the patients most likely to benefit from ICD implantation is not known.

METHODS AND RESULTS

In this extended follow-up analysis of the Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality (DANISH) trial, RV-FWS was measured with echocardiography in 445 patients before randomization. RV dysfunction was defined as an RV-FWS of greater than -20%. The primary end point was all-cause mortality. The median RV-FWS was -18% (quartiles -23% to -14%), and RV dysfunction was measured in 255 patients (57%). During a median follow-up of 5.7 years, 170 patients (38%) died. There was a statistically significant interaction between RV dysfunction and the effect of ICD implantation (P = .003), also after adjusting for known cardiovascular risk factors (P = .01). ICD implantation significantly decreased all-cause mortality in patients with RV dysfunction (hazard ratio 0.54, 95% confidence interval 0.36-0.80, P = .002), but not in patients with normal RV function (hazard ratio 1.34, 95% confidence interval 0.84-2.12, P = .22).

CONCLUSIONS

In patients with nonischemic systolic heart failure, RV dysfunction on echocardiography was associated with a greater effect of ICD implantation and could be used to select patients with benefit from ICD treatment.

Reduced inferior wall longitudinal strain is associated with malignant arrhythmias in non-ischemic heart failure

BACKGROUND

Reduced systolic myocardial function in the inferior region of the left ventricle has been suggested to be associated with malignant arrhythmias. We tested this hypothesis in patients with non-ischemic heart failure.

METHODS

Patients with non-ischemic heart failure (left ventricular ejection fraction [LVEF] < 35%) were evaluated by 2D-speckle-tracking echocardiography. The regional longitudinal strain was calculated for each of the six left ventricular walls. The reduced regional function was defined as strain below the median. The outcome was a composite of sudden cardiac death, admission with sustained ventricular arrhythmia, resuscitated cardiac arrest, and appropriate therapy from a primary prophylactic implantable cardioverter defibrillator. Time-to-first-event analysis was performed using a Cox model.

RESULTS

From two centers, 401 patients were included (median age: 63 years, 72% male) with a median LVEF of 25% (interquartile range [IQR] 20;30), and a median inferior wall strain of -9.0% (-12.5; -5.4). During a median follow-up of 4.0 years, 52 outcomes occurred. After multivariate adjustment for clinical and electrocardiographic parameters, inferior wall strain was independently associated with the outcome (HR 2.50 [1.35; 4.62], p = .003). No independent association was found between the composite outcome and reduced strain in any of the other left ventricular walls, Global Longitudinal Strain (HR 1.66 [0.93; 2.98], p = .09), or LVEF (HR 1.33 [0.75; 2.33], p = .33).

CONCLUSIONS

Below median strain in the left ventricular inferior region was independently associated with a 2.5-fold increase in the risk of malignant arrhythmias and sudden cardiac death in patients with non-ischemic heart failure.

Impact of Nationwide COVID-19 Lockdowns on the Implantation Rate of Cardiac Implantable Electronic Devices

AIM

The COVID-19 pandemic resulted in a significant decrease in the number of hospital admissions for severe emergent cardiovascular diseases during lockdowns worldwide. This study aimed to determine the impact of both the first and the second Danish nationwide lockdown on the implantation rate of cardiac implantable electronic devices (CIEDs).

METHODS

We retrospectively analysed the number of CIED implantations performed in Denmark and stratified them into 3-week intervals.

RESULTS

The total number of de novo CIED implantations decreased during the first lockdown by 15.5% and during the second by 5.1%. Comparing each 3-week interval using rate ratios, a significant decrease in the daily rates of the total number of de novo and replacement CIEDs (0.82, 95% CI [0.70, 0.96]), de novo CIEDs only (0.82, 95% CI [0.69, 0.98]), and non-acute pacemaker implantations (0.80, 95% CI [0.63, 0.99]) was observed during the first interval of the first lockdown. During the second lockdown (third interval), a significant decrease was seen in the daily rates of de novo CIEDs (0.73, 95% CI [0.55, 0.97]), and of pacemakers in total during both the second (0.78, 95% CI [0.62, 0.97]) and the third (0.60, 95% CI [0.42, 0.85]) intervals. Additionally, the daily rates of acute pacemaker implantation decreased during the second interval (0.47, 95% CI [0.27, 0.79]) and of non-acute implantation during the third interval (0.57, 95% CI [0.38, 0.84]). A significant increase was observed in the number of replacement procedures during the first interval of the second lockdown (1.70, 95% CI [1.04, 2.85]).

CONCLUSIONS

Our study found only modest changes in CIED implantations in Denmark during two national lockdowns.

Long term mortality in patients with hypertrophic cardiomyopathy - A Danish nationwide study

Background

Patients with hypertrophic cardiomyopathy (HCM) are generally regarded as having increased risk of arrhythmia, stroke, heart failure, and sudden cardiac death, but reported mortality rates vary considerably and originate from selected populations.

Study objective

We aimed to investigate the long-term mortality rate in a nationwide cohort of patients with HCM compared to a matched cohort from the general Danish population.

Methods

All patients with a first-time HCM diagnosis in Denmark between January 1, 2007 and December 31, 2018 were identified through nationwide registries. In the main analysis, two visits in an outpatient clinic were required in order to increase specificity. Patients were matched to controls from the background population in a 1:3 ratio based on age, sex, selected comorbidities and date of HCM. Mortalities were compared using Kaplan Meier estimator and multivariable Cox regression models.

Results

We identified 3126 patients with a first-time diagnosis of HCM. 1197 patients had at least two visits in the outpatient clinic (43 % female, median age 63.1 [25th-75th percentile 52.1-72.1] years). All-cause mortality was significantly higher in HCM patients than in matched controls: 10-year probabilities of death were 36.4 % (95 % CI 30.2-43.5 %) for HCM patients and 19.4 % (95 % CI 16.8-22.5 %) for controls. After adjusting for additional comorbidities and medications, a diagnosis with HCM was associated with an increased mortality rate (HR 1.48 (95 % CI 1.18-1.84, p = 0.001)).

Conclusion

Compared to matched controls from the background population, presence of HCM was associated with a significant increase in mortality rate.

Cholesterol not particle concentration mediates the atherogenic risk conferred by apolipoprotein B particles: a Mendelian randomization analysis

BACKGROUND AND AIMS

The causal contribution of apolipoprotein B (apoB) particles to coronary artery disease (CAD) is established. We examined whether this atherogenic contribution is better reflected by non-high-density lipoprotein cholesterol (non-HDL-C) or apoB particle concentration.

METHOD AND RESULTS

We performed Mendelian randomization (MR) analysis using 235 variants as genetic instruments; testing the relationship between their effects on the exposures, non-HDL-C and apoB, and on the outcome CAD using weighted regression. Variant effect estimates on the exposures came from the UK Biobank (N = 376 336) and on the outcome from a meta-analysis of five CAD datasets (187 451 cases and 793 315 controls). Subsequently, we carried out sensitivity and replication analyses.In univariate MR analysis, both exposures associated with CAD (βnon-HDL-C = 0.40, P = 2.8 × 10-48 and βapoB = 0.38, P = 1.3 × 10-44). Adding effects on non-HDL-C into a model that already included those on apoB significantly improved the genetically predicted CAD effects (P = 3.9 × 10-5), while adding apoB into the model including non-HDL-C did not (P = 0.69). Thirty-five per cent (82/235) of the variants used as genetic instruments had discordant effects on the exposures, associating with non-HDL-C/apoB ratio at P < 2.1 × 10-4 (0.05/235). Fifty-one variants associated at genome-wide significance.

CONCLUSION

Many sequence variants have discordant effects on non-HDL-C and apoB. These variants allowed us to show that the causal mechanism underlying the relationship between apolipoprotein B particles and CAD is more associated with non-HDL-C than apoB particle concentration.

Atrial fibrillation onset before heart failure or vice versa: what is worst? A nationwide register study

AIMS

Atrial fibrillation (AF) and heart failure (HF) often coexist. However, whether AF onset before HF or vice versa is associated with the worst outcome remains unclear. A consensus of large studies can guide future research and preventive strategies to better target high-risk patients.

METHODS AND RESULTS

We included all Danish cases with the coexistence of AF and HF (2005-17) using nationwide registries. Patients were divided into three separate groups (i) AF before HF, (ii) HF before AF, or (iii) AF and HF diagnosed concurrently (±30 days). Adjusting landmark Cox analyses (index date was the time of the latter diagnosis of AF or HF) were used for evaluating the association of the three groups with a composite outcome of ischaemic stroke or death. Among a total of 49 042 patients included, 40% had AF before HF, 27% had HF before AF, and 33% had AF and HF diagnosed concurrently. The composite endpoint accrued more often in patients with HF before AF compared to the two other groups (<0.001), and this remained significant in the adjusted analyses with hazard ratios (95% confidence intervals) of 1.26 (1.22-1.30) compared to AF before HF. Finally, antihypertensive treatment, oral anticoagulants, amiodarone, statins, and AF ablation were associated with a lower hazard ratio of the composite endpoint (all < 0.001).

CONCLUSIONS

In this large Danish national cohort, diagnosis of HF before AF was associated with an increased absolute risk of death compared to AF before HF and AF and HF diagnosed concurrently. Antihypertensive treatment, oral anticoagulants, amiodarone, statins, and AF ablation may improve prognosis.

Family screening in dilated cardiomyopathy-qualifying screening and need for follow-up

Background

Guidelines recommend family screening in dilated cardiomyopathy to uncover pre-symptomatic disease to improve morbidity and mortality through early treatment. According to patterns of inheritance and incomplete penetrance, less than half of relatives to dilated cardiomyopathy probands will develop disease, but so far, no guidelines provide recommendations on the frequency and intensity of follow-up screening.

Purpose

To investigate the prevalence and incidence and identify predictors of developing familial dilated cardiomyopathy (FDC) in relatives participating in family screening.

Methods

The study was an observational, longitudinal cohort study of families screened and followed from 2006 to 2020, at a regional assembly of clinics for inherited cardiomyopathies in Denmark.

Results

We included 211 families totaling 774 subjects (n=563 relatives, 47% women). At baseline, 124 relatives (22%) were diagnosed with dilated cardiomyopathy, while 43 relatives (8%) not fulfilling FDC criteria were found to carry class IV to V genetic variants. Thus, the combined clinical and genetic yield of screening was 30% at baseline. Relatives not fulfilling diagnostic criteria for FDC at baseline (n=439), were stratified into four groups based on results from genetic screening and clinical work-up at baseline (Figure 1). The risk of developing FDC during follow-up was strongly associated with this classification (see figure 1 and 2). The highest risk of developing FDC was observed in relatives carrying class IV to V genetic variants (n=43, age-adjusted incidence rate of 10% per person-year), while none of the subjects identified as non-carriers of family variants developed disease (n=58). In subjects sub-grouped according to baseline-findings on ECG and echocardiography, relatives with abnormal (n=70) vs normal (n=268) findings had markedly higher incidence rates of FDC (overall 4.7% vs 0.4% per person-year), regardless of age-group (Figures 1 and 2). The relatives with abnormal ECG and/or echocardiographic findings at baseline had a (age-group-adjusted) hazard ratio of 12.9 (CI: 4.8 to 35.1, p&lt;0.001), when compared to relatives with normal findings.

Conclusion

Family screening identified a genetic predisposition to or overt FDC in 30% of screened relatives at baseline. In relatives not fulfilling criteria for FDC at baseline, findings from genetic testing and/or non-diagnostic findings on echocardiography and/or ECG were strongly associated with progression to disease. Importantly, relatives with normal genetic or objective findings had a low incidence rate and overall risk of developing FDC. Thus, baseline-screening identified a large proportion of relatives, in whom follow-up can be considered to be reduced allowing focused follow-up of relatives at higher risk of progression.

Funding Acknowledgement

Type of funding sources: None.

Cardiac resynchronisation therapy and implantable cardioverter-defibrillator in non-ischaemic systolic heart failure: extended follow-up of the DANISH trial

Background

In the Danish Study to Assess the Efficacy of Implantable Cardioverter-Defibrillators [ICDs] in Patients with Non-ischaemic Systolic Heart Failure on Mortality (DANISH) trial, ICD implantation did not provide an overall survival benefit in patients with non-ischaemic systolic heart failure. A high proportion of patients in the DANISH trial received a cardiac resynchronisation therapy (CRT) device, which improves the prognosis in patients with heart failure. Therefore, it is of interest to examine whether the effect of ICD implantation in patients with non-ischaemic systolic heart failure is modified by CRT.

Purpose

Adding 4 years of additional follow-up to the DANISH trial, we examined the effect of ICD implantation according to status with respect to CRT implantation at baseline.

Methods

In the DANISH trial, 556 patients with non-ischaemic systolic heart failure were randomised to receive an ICD and 560 to receive usual clinical care (control). Patients fulfilling indications for a CRT device received a CRT-defibrillator (if randomised to ICD arm) or CRT-pacemaker (if randomised to control arm). In the ICD group, 322 patients (57.9%) received a CRT device; in the control group, 323 patients (57.7%) received a CRT device. In this extended follow-up study, patients were followed until May 18, 2020. The primary outcome was death from any cause; secondary outcomes were cardiovascular death and sudden cardiovascular death.

Results

During a median follow-up of 9.5 years, the ICD group did not have significantly lower all-cause mortality compared with the control group (hazard ratio [HR] 0.89 [95% CI, 0.74–1.08]). The results were independent of whether the patient received a CRT device at randomisation (patients with a CRT device: HR 0.92 [95% CI, 0.72–1.18]; patients without a CRT device: HR 0.86 [95% CI, 0.64–1.14]; P for interaction, 0.72). Similarly, ICD implantation did not reduce rates of cardiovascular death overall (HR 0.87 [95% CI, 0.70–1.09]), and this association was not modified by CRT (patients with a CRT device: HR 0.89 [95% CI, 0.66–1.19]; patients without a CRT device: HR 0.85 [95% CI, 0.60–1.20]; P for interaction, 0.86). The ICD group had significantly lower rates of sudden cardiovascular death in the overall population (HR, 0.60 [95% CI, 0.40–0.92]), and this association was not modified by CRT (patients with a CRT device: HR 0.69 [95% CI, 0.40–1.21]; patients without a CRT device: HR 0.51 [95% CI, 0.26–0.97]; P for interaction, 0.47). See Figure 1 for all results.

Conclusions

In this extended follow-up study of the DANISH trial, the effect of ICD implantation in patients with non-ischaemic systolic heart failure was not modified by CRT.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The DANISH trial was supported by unrestricted grants from Medtronic, St Jude Medical, Tryg Fonden, and the Danish Heart Foundation. No further funding was obtained for this follow-up study.

Efficacy of Implantable Cardioverter Defibrillator in Nonischemic Systolic Heart Failure According to Sex: Extended Follow-Up Study of the DANISH Trial

BACKGROUND

Men and women may respond differently to certain therapies for heart failure with reduced ejection fraction, including implantable cardioverter defibrillators (ICD). In an extended follow-up study of the DANISH trial (Danish Study to Assess the Efficacy of ICDs in Patients With Non-Ischemic Systolic Heart Failure on Mortality), adding 4 years of additional follow-up, we examined the effect of ICD implantation according to sex.

METHODS

In the DANISH trial, 1116 patients with nonischemic systolic heart failure were randomized to receive an ICD (N=556) or usual clinical care (N=550). The primary outcome was all-cause mortality.

RESULTS

Of the 1116 patients randomized in the DANISH trial, 307 (27.5%) were women. During a median follow-up of 9.5 years, women had a lower associated rate of all-cause mortality (hazard ratio [HR], 0.60 [95% CI, 0.47-0.78]) cardiovascular death (HR, 0.62 [95% CI, 0.46-0.84]), nonsudden cardiovascular death (HR, 0.59 [95% CI, 0.42-0.85]), and a numerically lower rate of sudden cardiovascular death (HR, 0.70 [95% CI, 0.40-1.25]), compared with men. Compared with usual clinical care, ICD implantation did not reduce the rate of all-cause mortality, irrespective of sex (men, HR, 0.85 [95% CI, 0.69-1.06]; women, HR, 0.98 [95% CI, 0.64-1.50]; Pinteraction=0.51). In addition, sex did not modify the effect of ICD implantation on sudden cardiovascular death (men, HR, 0.57 [95% CI, 0.36-0.92]; women, HR, 0.68 [95% CI, 0.26-1.77]; Pinteraction=0.76).

CONCLUSIONS

In patients with nonischemic systolic heart failure, ICD implantation did not provide an overall survival benefit, but reduced sudden cardiovascular death, irrespective of sex.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT00542945.

NT-proBNP and ICD in Nonischemic Systolic Heart Failure: Extended Follow-Up of the DANISH Trial

OBJECTIVES

In this extended follow-up study of the DANISH (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-ischemic Systolic Heart Failure on Mortality) trial, adding 4 years of additional follow-up, we examined the effect of implantable cardioverter-defibrillator (ICD) implantation according to baseline N-terminal pro-B-type natriuretic peptide (NT-proBNP) level.

BACKGROUND

In the DANISH trial, NT-proBNP level at baseline appeared to modify the response to ICD implantation.

METHODS

In the DANISH trial, 1,116 patients with nonischemic systolic HF were randomized to receive an ICD (N = 556) or usual clinical care (N = 550). Outcomes were analyzed according to NT-proBNP levels (below/above median) at baseline. The primary outcome was death from any cause.

RESULTS

All 1,116 patients in the DANISH trial had an available NT-proBNP measurement at baseline (median: 1,177 pg/mL; range: 200-22,918 pg/mL). There was a trend toward a reduction in all-cause death with ICD implantation, compared with usual clinical care, in patients with NT-proBNP levels lower than the median (HR: 0.75 [95% CI: 0.55-1.03]), but not in those with higher NT-proBNP levels (HR: 0.95 [95% CI: 0.74-1.21]) (P_interaction = 0.28). Similarly, ICD implantation significantly reduced the rate of cardiovascular (CV) and sudden cardiovascular death (SCD) in patients with NT-proBNP levels lower than the median (CV death, HR: 0.69 [95% CI: 0.47-1.00]; SCD, HR: 0.37 [95% CI: 0.19-0.75]), but not in those with higher levels (CV death, HR: 0.94 [95% CI: 0.70-1.25]; SCD, HR: 0.86 [95% CI: 0.49-1.51]) (P_interaction = 0.20 and 0.08 for CV death and SCD, respectively).

CONCLUSIONS

Lower baseline NT-proBNP levels could identify patients with nonischemic systolic HF who may derive benefit from ICD implantation. (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-ischemic Systolic Heart Failure on Mortality [DANISH]; NCT00542945).

Association between common cardiovascular risk factors and clinical phenotype in patients with hypertrophic cardiomyopathy from the European Society of Cardiology (ESC) EurObservational Research Programme (EORP) Cardiomyopathy/Myocarditis registry

AIMS

The interaction between common cardiovascular risk factors (CVRF) and hypertrophic cardiomyopathy (HCM) is poorly studied. We sought to explore the relation between CVRF and the clinical characteristics of patients with HCM enrolled in the EURObservational Research Programme (EORP) Cardiomyopathy registry.

METHODS AND RESULTS

1739 patients with HCM were studied. The relation between hypertension (HT), diabetes (DM), body mass index (BMI), and clinical traits was analysed. Analyses were stratified according to the presence or absence of a pathogenic variant in a sarcomere gene. The prevalence of HT, DM, and obesity (Ob) was 37, 10, and 21%, respectively. HT, DM, and Ob were associated with older age (P<0.001), less family history of HCM (HT and DM P<0.001), higher New York Heart Association (NYHA) class (P<0.001), atrial fibrillation (HT and DM P<0.001; Ob p = 0.03) and LV (left ventricular) diastolic dysfunction (HT and Ob P<0.001; DM P = 0.003). Stroke was more frequent in HT (P<0.001) and mutation-positive patients with DM (P = 0.02). HT and Ob were associated with higher provocable LV outflow tract gradients (HT P<0.001, Ob P = 0.036). LV hypertrophy was more severe in Ob (P = 0.018). HT and Ob were independently associated with NYHA class (OR 1.419, P = 0.017 and OR 1.584, P = 0.004, respectively). Other associations, including a higher proportion of females in HT and of systolic dysfunction in HT and Ob, were observed only in mutation-positive patients.

CONCLUSION

Common CVRF are associated with a more severe HCM phenotype, suggesting a proactive management of CVRF should be promoted. An interaction between genotype and CVRF was observed for some traits.

Reduced longitudinal strain in the left ventricular inferior wall predicts malignant arrhythmia in non-ischemic heart failure. A DANISH substudy

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

Small studies have suggested that poor regional myocardial function may be associated with malignant arrhythmias, in particular around the inferior-posterior region. We tested this hypothesis in a subgroup of patients from the DANISH trial.

METHODS

From two centers, 317 patients with non-ischemic heart failure (LVEF &lt; 35%) from the DANISH trial were evaluated by 2D-strain echocardiography. Regional strain was calculated as the average longitudinal strain in basal-, midventricular- and apical segments in each of the six left ventricular walls. Reduced regional function was defined as below-median regional strain. The endpoint was a composite of sudden cardiac death (SCD), sustained VT, admission with ventricular arrhythmia, and appropriate therapy from a primary prophylactic ICD. Time-to-first-event analysis was performed using Cox models.

RESULTS

Mean age at inclusion was 62 years (72% male), median LVEF was 25% (IQR 20-30) median inferior strain was -8.7% (IQR -12.3; -4.9). After a five-year follow-up, 43 events were observed. Reduced inferior strain was associated with the composite endpoint in univariate analysis with a HR 2.08(95% CI 1.11-3.90), P = 0.021. After multivariate adjustment for clinical and echocardiographic parameters, inferior strain remained an independent predictor with a HR 2.78(95% CI 1.39–5.56), P = 0.004. Strain measurements in no other region were associated with the endpoint in the multivariate analysis. In subgroup analysis of patients in the two lower age tertiles (&lt;68 of age) we found that reduced inferior- and posterior strain were associated with development of the composite endpoint after multivariate adjustment with HRs of 3.25(95% CI 1.41-7.53), P = 0.006 and 2.51(95% CI 1.14-5.53), P = 0.022.

CONCLUSIONS

Low inferior-posterior strain was associated with a 2-3-fold increase in risk of malignant arrhythmia and SCD in patients with non-ischemic heart failure. Abstract Figure.

Effect of implantable cardioverter-defibrillators in patients with non-ischaemic systolic heart failure and concurrent coronary atherosclerosis

Aims

Prophylactic implantable cardioverter‐defibrillators (ICD) reduce mortality in patients with ischaemic heart failure (HF), whereas the effect of ICD in patients with non‐ischaemic HF is less clear. We aimed to investigate the association between concomitant coronary atherosclerosis and mortality in patients with non‐ischaemic HF and the effect of ICD implantation in these patients.

Methods and results

Patients were included from DANISH (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non‐Ischaemic Systolic Heart Failure on Mortality), randomizing patients to ICD or control. Study inclusion criteria for HF were left ventricular ejection fraction ≤ 35% and increased levels (>200 pg/mL) of N‐terminal pro‐brain natriuretic peptide. Of the 1116 patients from DANISH, 838 (75%) patients had available data from coronary angiogram and were included in this subgroup analysis. We used Cox regression to assess the relationship between coronary atherosclerosis and mortality and the effect of ICD implantation. Of the included patients, 266 (32%) had coronary atherosclerosis. Of these, 216 (81%) had atherosclerosis without significant stenoses, and 50 (19%) had significant stenosis. Patients with atherosclerosis were significantly older {67 [interquartile range (IQR) 61–73] vs. 61 [IQR 54–68] years; P < 0.0001}, and more were men (77% vs. 70%; P = 0.03). During a median follow‐up of 64.3 months (IQR 47–82), 174 (21%) of the patients died. The effect of ICD on all‐cause mortality was not modified by coronary atherosclerosis [hazard ratio (HR) 0.94; 0.58–1.52; P = 0.79 vs. HR 0.82; 0.56–1.20; P = 0.30], P for interaction = 0.67. In univariable analysis, coronary atherosclerosis was a significant predictor of all‐cause mortality [HR, 1.41; 95% confidence interval (CI), 1.04–1.91; P = 0.03]. However, this association disappeared when adjusting for cardiovascular risk factors (age, gender, diabetes, hypertension, smoking, and estimated glomerular filtration rate) (HR 1.05, 0.76–1.45, P = 0.76).

Conclusions

In patients with non‐ischaemic systolic heart failure, ICD implantation did not reduce all‐cause mortality in patients either with or without concomitant coronary atherosclerosis. The concomitant presence of coronary atherosclerosis was associated with increased mortality. However, this association was explained by other risk factors.

Periodic Repolarization Dynamics Identifies ICD-responders in Non-ischemic Cardiomyopathy: A DANISH Substudy

Background: Identification of patients with non-ischemic cardiomyopathy who benefit from prophylactic implantation of a cardioverter-defibrillator (ICD) remains an unmet clinical need. We hypothesized that periodic repolarization dynamics (PRD), a marker of repolarization instability associated with sympathetic activity, could be used to identify patients that benefit from prophylactic ICD-implantation. Methods: Heart-failure (DANISH) study, in which patients with non-ischemic cardiomyopathy, left-ventricular ejection fraction (LVEF) ≤35% and elevated N-terminal pro-brain natriuretic peptides (NT-proBNP) were randomized to ICD-implantation or control group. Patients were included in the PRD-substudy if they had a 24-hour Holter monitor recording at baseline with technically acceptable ECG signals during the night hours (00:00-06.00 AM). PRD was assessed using wavelet analysis according to previously validated methods. Primary endpoint was all-cause mortality. Cox-regression models were adjusted for age, sex, NT-proBNP, estimated glomerular filtration rate, LVEF, atrial fibrillation, ventricular pacing, diabetes mellitus, cardiac resynchronization therapy and mean heart rate. We proposed PRD ≥10deg² as exploratory cut-off value for ICD-implantation. Results: Seven-hundred and forty-eight of the 1,116 DANISH patients qualified for the PRD-substudy. During a mean follow-up period of 5.1±2.0 years, 82 of 385 patients died in the ICD group and 85 of 363 patients died in the control group (p-value=0.40). In Cox-regression analysis, PRD was independently associated with mortality (HR 1.28 [1.09-1.50] per SD increase; p-value = 0.003). Moreover, PRD was significantly associated with mortality in the control group (HR 1.51 [1.25-1.81]; p<0.001) but not in the ICD-group 1.04 [0.83-1.54]; p-value=0.71). There was a significant interaction between PRD and the effect of ICD-implantation on mortality (p-value 0.008), with patients with higher PRD having the greater benefit in terms of mortality reduction. ICD-implantation was associated with an absolute mortality reduction of 17.5% in the 280 patients with PRD ≥10deg² (HR 0.54 [0.34-0.84]; p-value=0.006; number needed to treat 6), but not in the 468 patients with PRD<10deg² (HR 1.17 [0.77-1.78]; p-value=0.46; p-value for interaction 0.01). Conclusions: Increased PRD identified patients with non-ischemic cardiomyopathy, where prophylactic ICD-implantation led to significant mortality reduction.

Long-term Follow-up of the The Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality (DANISH)

Background: The Danish Study to Assess the Efficacy of Implantable Cardioverter-Defibrillators (ICDs) in Patients with Non-ischemic Systolic Heart Failure on Mortality (DANISH) found that primary-prevention ICD implantation was not associated with an overall survival benefit in patients with non-ischemic systolic heart failure during a median follow-up of 5.6 years, though there was a beneficial effect on all-cause mortality in patients ≤70 years. This study presents an additional four years of follow-up data from DANISH. Methods: In DANISH, 556 patients with non-ischemic systolic heart failure were randomized to receive an ICD and 560 to receive usual clinical care and followed until June 30, 2016. In this long-term follow-up study, patients were followed until May 18, 2020. Analyses were conducted for the overall population and according to age (≤70 and >70 years). Results: During a median follow-up of 9.5 years (25^th-75^th percentile, 7.9-10.9 years), 208/556 patients (37%) in the ICD group and 226/560 patients (40%) in the control group died. Compared with the control group, the ICD group did not have significantly lower all-cause mortality (HR 0.89 [95%CI,0.74-1.08]; P=0.24). In patients ≤70 years (n=829), all-cause mortality was lower in the ICD group than the control group (117/389 [30%] vs 158/440 [36%]; HR 0.78 [95%CI,0.61-0.99]; P=0.04), whereas in patients >70 years (n=287), all-cause mortality was not significantly different between the ICD and control group (91/167 [54%] vs 68/120 [57%]; HR 0.92 [95%CI,0.67-1.28]; P=0.75). Cardiovascular death showed similar trends (overall, 147/556 [26%] vs 164/560 [29%], HR 0.87 [95%CI,0,70-1.09], P=0.20; ≤70 years, 87/389 [22%] vs 122/440 [28%], HR 0.75 [95%CI,0.57-0.98], P=0.04; >70 years, 60/167 [36%] vs 42/120 [35%], HR 0.97 [95%CI,0.65-1.45], P=0.91). The ICD group had a significantly lower incidence of sudden cardiovascular death in the overall population (35/556 [6%] vs 57/560 [10%]; HR 0.60 [95%CI,0.40-0.92]; P=0.02) and in patients ≤70 years (19/389 [5%] vs 49/440 [11%]; HR 0.42 [95%CI,0.24-0.71]; P=0.0008), but not in patients >70 years (16/167 [10%] vs 8/120 [7%]; HR 1.34 [95%CI,0.56-3.19]; P=0.39). Conclusions: During a median follow-up of 9.5 years, ICD implantation did not provide an overall survival benefit in patients with non-ischemic systolic heart failure. In patients ≤70 years, ICD implantation was associated with a lower incidence of all-cause mortality, cardiovascular death, and sudden cardiovascular death. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00542945.

Prevalence and prognostic association of ventricular arrhythmia in non-ischaemic heart failure patients: results from the DANISH trial

AIMS

Improved risk stratification to identify non-ischaemic heart failure patients who will benefit from primary prophylactic implantable cardioverter-defibrillator (ICD) is needed. We examined the potential of ventricular arrhythmia to identify patients who could benefit from an ICD.

METHODS AND RESULTS

A total of 850 non-ischaemic systolic heart failure patients with left ventricle ≤35% and elevated N-terminal pro-brain natriuretic peptides had a 24-h Holter monitor recording performed. We examined present non-sustained ventricular tachycardia (NSVT), defined as ≥3 consecutive premature ventricular contractions (PVCs) with a rate of ≥100/min, and number of PVCs per hour stratified into low (<30) and high burden (≥30) groups. Outcome measures were overall mortality, sudden cardiac death (SCD), and cardiovascular death (CVD). In total, 193 patients died, 49 from SCD and 125 from CVD. Non-sustained ventricular tachycardia (365 patients) was significantly associated with increased all-cause mortality [hazard ratio (HR) 1.47; 95% confidence interval (CI) 1.07-2.03; P = 0.02] and to CVD (HR 1.89; CI 1.25-2.87; P = 0.003). High burden PVC (352 patients) was associated with increased all-cause mortality (HR1.38; CI 1.00-1.90; P = 0.046) and with CVD (HR 1.78; CI 1.19-2.66; P = 0.005). There was no statistically significant association with SCD for neither NSVT nor PVC. In interaction analyses, neither NSVT (P = 0.56) nor high burden of PVC (P = 0.97) was associated with survival benefit from ICD implantation.

CONCLUSION

Ventricular arrhythmia in non-ischaemic heart failure patients was associated with a worse prognosis but could not be used to stratify patients to ICD implantation.

Atrial fibrillation is a marker of increased mortality risk in nonischemic heart failure-Results from the DANISH trial

BACKGROUND

Atrial fibrillation (AF) in heart failure (HF) patients has been associated with a worse outcome. Similarly, excessive supraventricular ectopic activity (ESVEA) has been linked to development of AF, stroke, and death. This study aimed to investigate AF and ESVEA's association with outcomes and effect of prophylactic implantable cardioverter defibrillator (ICD) implantation in nonischemic HF patients.

METHODS

A total of 850 patients with nonischemic HF, left ventricle ejection fraction ≤35%, and elevated N-terminal pro-brain natriuretic peptides underwent 24 hours Holter recording. The presence of AF (≥30 seconds) and ESVEA (≥30 supraventricular ectopic complexes (SVEC) per hour or run of SVEC ≥20 beats) were registered. Outcomes were all-cause mortality, cardiovascular death (CVD), and sudden cardiac death (SCD).

RESULTS

AF was identified in 188 patients (22%) and ESVEA in 84 patients (10%). After 4 years and 11 months of follow-up, a total of 193 patients (23%) had died. AF was associated with all-cause mortality (hazard ratio [HR] 1.44; confidence interval [CI] 1.04-1.99; P = .03) and CVD (HR 1.59; CI 1.07-2.36; P = .02). ESVEA was associated with all-cause mortality (HR 1.73; CI 1.16-2.57; P = .0073) and CVD (HR 1.76; CI 1.06-2.92; P = .03). Neither AF nor ESVEA was associated with SCD. ICD implantation was not associated with an improved prognosis for neither AF (P value for interaction = .17), nor ESVEA (P value for interaction = .68).

CONCLUSIONS

Both AF and ESVEA were associated with worsened prognosis in nonischemic HF. However, ICD implantation was not associated with an improved prognosis for either group.

The effect of implantable cardioverter-defibrillator in patients with diabetes and non-ischaemic systolic heart failure

AIMS

Implantable cardioverter-defibrillator (ICD) implantation reduce the risk of sudden cardiac death, but not all-cause death in patients with non-ischaemic systolic heart failure (HF). Whether co-existence of diabetes affects ICD treatment effects is unclear.

METHODS AND RESULTS

We examined the effect of ICD implantation on risk of all-cause death, cardiovascular death, and sudden cardiac death (SCD) according to diabetes status at baseline in the Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischaemic Systolic Heart Failure on Mortality (DANISH) trial. Outcomes were analysed by use of cumulative incidence curves and Cox regressions models. Of the 1116 patients enrolled, 211 (19%) had diabetes at baseline. Patients with diabetes were more obese, had worse kidney function and more were in New York Heart Association Class III/IV. The risk of device infections and other complications in the ICD group was similar among patients with and without diabetes (6.1% vs. 4.6% P = 0.54). Irrespective of treatment group, diabetes was associated with higher risk of all-cause death, cardiovascular death, and SCD. The treatment effect of ICD in patients with diabetes vs. patients without diabetes was hazard ratio (HR) = 0.92 (0.57-1.50) vs. HR = 0.85 (0.63-1.13); Pinteraction = 0.60 for all-cause mortality, HR = 0.99 (0.58-1.70) vs. HR = 0.70 (0.48-1.01); Pinteraction = 0.25 for cardiovascular death, and HR = 0.81 (0.35-1.88) vs. HR = 0.40 (0.22-0.76); Pinteraction = 0.16 for sudden cardiac death.

CONCLUSION

Among patients with non-ischaemic systolic HF, diabetes was associated with higher incidence of all-cause mortality, primarily driven by cardiovascular mortality including SCD. Treatment effect of ICD therapy was not significantly modified by diabetes which might be due to lack of power.

Rubidium-82 positron emission tomography for detection of acute doxorubicin-induced cardiac effects in lymphoma patients

BACKGROUND

Doxorubicin is a cornerstone in lymphoma treatment, but is limited by dose-dependent cardiotoxicity. Rubidium-82 positron emission tomography (82Rb PET) assesses coronary microvascular function through absolute quantification of myocardial perfusion and myocardial perfusion reserve (MPR). Doxorubicin-induced microvascular injury represents a potential early marker of cardiotoxicity.

METHODS AND RESULTS

We included 70 lymphoma patients scheduled for doxorubicin-based treatment. Cardiotoxicity was evaluated with 82Rb PET myocardial perfusion imaging during rest and adenosine stress before chemotherapy and shortly after the first doxorubicin exposure. Patients with a MPR decline > 20% were defined as having a low threshold for cardiotoxicity. In the 54 patients with complete data sets, MPR was significantly lower after the initial doxorubicin exposure (2.69 vs 2.51, P = .03). We registered a non-significant decline in stress perfusion (3.18 vs 3.02 ml/g/min, P = .08), but no change in resting myocardial perfusion. There were 13 patients with a low cardiotoxic threshold. These patients had a significantly higher age, but were otherwise similar to the remaining part of the study population.

CONCLUSION

Decreases in MPR after initial doxorubicin exposure in lymphoma patients may represent an early marker of doxorubicin-induced cardiotoxicity. The prognostic value of acute doxorubicin-induced changes in MPR remains to be investigated.

123I-MIBG for detection of subacute doxorubicin-induced cardiotoxicity in patients with malignant lymphoma

BACKGROUND

Doxorubicin is the mainstay of curative lymphoma treatment but is associated with a dose-dependent cardiotoxicity that is often recognized too late to avoid substantial irreversible cardiac injury. Iodine-123 metaiodobenzylguanidine (123I-MIBG) is a gamma-emitting tracer that mimics noradrenaline uptake, storage, and release mechanisms in adrenergic presynaptic neurons. 123I-MIBG scintigraphy can be used for assessment of doxorubicin-induced injury to myocardial adrenergic neurons during treatment and could be the tool for early detection of doxorubicin cardiotoxicity, which is currently lacking.

METHODS AND RESULTS

A total of 37 lymphoma patients scheduled for doxorubicin treatment were included in our study. 123I-MIBG imaging was performed prior to chemotherapy and after a median of 4 cycles of doxorubicin. Early and late heart-to-mediastinum ratios (H/Mearly and H/Mlate) and washout rate (WOR) were used for evaluation of cardiotoxicity. The prognostic value of 123I-MIBG results was assessed using left ventricular ejection fraction (LVEF) as measured by cardiac magnetic resonance at 1-year follow-up. We found a post-therapy increase in WOR (including nine patients with > 10% increase), which was not statistically significant (18.6 vs 23.4%, P = 0.09). The difference appeared to be driven by an increase in H/Mearly. LVEF decreased from baseline to 1-year follow-up (64 vs 58%, P = 0.03). LVEF change was not associated with changes in WOR (P = 0.5).

CONCLUSION

The present study does not provide evidence for 123I-MIBG imaging as a clinically applicable tool for early detection of doxorubicin-induced cardiotoxicity.

Myocardial fibrosis and the effect of primary prophylactic defibrillator implantation in patients with non-ischemic systolic heart failure-DANISH-MRI

AIMS

Patients with non-ischemic systolic heart failure have an increased risk of sudden cardiac death (SCD). Myocardial fibrosis, detected as late gadolinium enhancement (LGE) with cardiac magnetic resonance (CMR), has been shown to predict all-cause mortality. We hypothesized that LGE can identify patients with non-ischemic heart failure who will benefit from ICD implantation.

METHODS AND RESULTS

In this prospective observational sub-study of the Danish Study to Assess the Efficacy of ICDs in Patients with Nonischemic Systolic Heart Failure on Mortality (DANISH), 252 patients underwent CMR. LGE was quantified by the full width/half maximum method. The primary endpoint was all-cause mortality. LGE could be adequately assessed in 236 patients, median age was 61 years and median duration of heart failure was 14 months; there were 108 patients (46%) randomized to ICD. Median follow-up time was 5.3 years. Median left ventricular ejection fraction on CMR was 35%. In all, 50 patients died. LGE was present in 113 patients (48%). The presence of LGE was an independent predictor of all-cause mortality (HR 1.82; 95% CI 1.002-3.29; P = .049) after adjusting for known cardiovascular risk factors. ICD implantation did not impact all-cause mortality, for either patients with LGE (HR 1.18; 95% CI 0.59-2.38; P = .63), or for patients without LGE (HR 1.00; 95% CI 0.39-2.53; P = .99), (P for interaction =0.79).

CONCLUSION

In patients with non-ischemic systolic heart failure, LGE predicted all-cause mortality. However, in this cohort, LGE did not identify a group of patients who survived longer by receiving an ICD.

P2627Diffuse coronary artery disease and effect of implantable cardioverter-defibrillators in patients with non-ischaemic systolic heart failure

Background

Implantable defibrillators reduce mortality in patients with ischaemic heart failure. The recent Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients With Non-Ischaemic Systolic Heart Failure on Mortality (DANISH) found no overall effect on all-cause mortality with ICD implantation. Coronary artery disease (CAD) as the cause of heart failure had to be ruled out prior to inclusion into DANISH, but patients could have diffuse atherosclerosis, one- or two-vessel disease on the qualifying coronary angiogram if the investigator did not find that the degree of CAD could explain the severely reduced left ventricular ejection fraction. It is unknown if concomitant coronary atherosclerosis is related to outcome in patients with non-ischaemic cardiomyopathy and whether the effect of implanting an ICD is different in patients with non-ischaemic cardiomyopathy and coronary atherosclerosis.

Purpose

The aim of this study was to investigate the association between coronary atherosclerosis and all-cause mortality in patients with non-ischaemic systolic heart failure and the effect of ICD implantation in these patients.

Methods

Of the 1116 patients from the DANISH study, 838 patients with available coronary angiography data were included in this subgroup analysis. Patients were considered to have coronary atherosclerosis if the invasive cardiologist described diffuse atherosclerosis or coronary stenosis. We used cox regression to assess the relationship between coronary atherosclerosis and mortality and between ICD implantation and mortality in patients with and without coronary atherosclerosis. Data are presented as hazard ratios with 95% confidence intervals.

Results

Of the 838 patients, 266 (32%) had coronary atherosclerosis, 216 (81%) of whom were reported as having atherosclerosis without stenoses. Patients with coronary atherosclerosis were significantly older (median age 67 years vs 61 years), more often male (77% vs 70%) and had a higher prevalence of diabetes (30% vs 17%).

In univariable analysis, coronary atherosclerosis was a significant predictor of all-cause mortality (HR, 1.41; 95% CI, 1.04–1.91; P=0.03). However, the association between coronary atherosclerosis and all-cause mortality disappeared when adjusting for age, gender and diabetes (HR 1.02, 0.75–1.41, P=0.88). Adjusted hazard ratios are shown in Figure 1.

There was no association between ICD treatment and all-cause mortality in patients with or without coronary atherosclerosis (HR 0.94; 0.58–1.52; P=0.79 vs HR 0.82; 0.56–1.20; P=0.30), P for interaction=0.67.

Figure 1

Conclusions

In patients with non-ischaemic systolic heart failure, the concomitant presence of coronary atherosclerosis was associated with increased mortality. However, this association was not independent of other risk factors. ICD implantation was not associated with mortality risk in patients either with or without concomitant coronary atherosclerosis.

Acknowledgement/Funding

TrygFonden (Copenhagen, DK), Medtronic (US) and St. Jude Medical (US)

P4533Duration of heart failure and effect of defibrillator implantation in patients with non-ischemic systolic heart failure

Introduction

Patients with non-ischemic systolic heart failure have increased risk of sudden cardiac death (SCD) and death from progressive pump failure. Whether the risk of SCD changes over time is unknown. We seek to investigate the relationship between duration of heart failure, mode of death, and effect of implantable cardioverter defibrillator (ICD) implantation.

Methods

We examined the risk of all-cause death and SCD according to the duration of heart failure among patients with non-ischemic systolic heart failure enrolled in the Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality (DANISH) trial. Patients were divided according to quartiles of heart failure duration (Q1 ≤8 months, Q2 9 ≤18 months, Q3 19 ≤65 months, Q4 ≥66 months).

Results

A total number of 1116 patients were included. Patients with the longest duration of heart failure were older, more often men, had more comorbidity, and more often received cardiac resynchronizing therapy device. Doubling of heart failure duration was an independent predictor of both all-cause mortality (HR 1.26 95% CI 1.17–1.37, p<0.0001), and SCD (HR 1.29 95% CI 1.11–1.49, p=0.0009). The proportion of deaths caused by SCD was not different between heart failure quartiles (p=0.91), and the effect of ICD implantation on all-cause mortality was not modified by the duration of heart failure (p=0.59).

Duration of heart failure and death

Conclusions

Duration of heart failure predicted both all-cause mortality and risk of SCD independently of other risk indicators. However, the proportion of death caused by SCD did not change with longer duration of heart failure and the effect of ICD was not modified by the duration of heart failure.

Acknowledgement/Funding

The work was sponsored by The Danish Heart Foundation (Hjerteforeningen) and the Lundbeck Foundation (Lundbeckfonden). The DANISH trial was supported

Duration of Heart Failure and Effect of Defibrillator Implantation in Patients With Nonischemic Systolic Heart Failure

BACKGROUND

Patients with nonischemic systolic heart failure (HF) have increased risk of sudden cardiac death (SCD) and death from progressive pump failure. Whether the risk of SCD changes over time is unknown. We seek here to investigate the relation between duration of HF, mode of death, and effect of implantable cardioverter-defibrillator implantation.

METHODS AND RESULTS

We examined the risk of all-cause death and SCD according to the duration of HF among patients with nonischemic systolic HF enrolled in the DANISH (Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality). In all, 1116 patients were included. Patients were divided according to quartiles of HF duration (≤8, 9≤18, 19≤65, and ≥66 months). Patients with the longest duration of HF were older, more often men, had more comorbidity, and more often received a cardiac resynchronization therapy device. Doubling of HF duration was an independent predictor of both all-cause mortality (hazard ratio [HR], 1.27; 95% CI, 1.17-1.38; P<0.0001), and SCD (HR, 1.29; 95% CI, 1.11-1.50; P=0.0007). The proportion of deaths caused by SCD was not different between HF quartiles (P=0.91), and the effect of implantable cardioverter-defibrillator implantation on all-cause mortality was not modified by the duration of HF (P=0.59).

CONCLUSIONS

Duration of HF predicted both all-cause mortality and risk of SCD independently of other risk indicators. However, the proportion of death caused by SCD did not change with longer duration of HF, and the effect of implantable cardioverter-defibrillator was not modified by the duration of HF.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00542945.

Impaired myocardial perfusion is associated with increasing end-systolic- and end-diastolic volumes in patients with non-ischemic systolic heart failure: a cross-sectional study using Rubidium-82 PET/CT

BACKGROUND

Myocardial flow reserve (MFR, stress/rest myocardial blood flow) is a strong marker of myocardial vasomotor function. MFR is a predictor of adverse cardiac events in patients with non-ischemic systolic heart failure and previous studies using different methods have found association between myocardial blood flow and left ventricular dilatation. The aim of this study was to investigate whether there is an association between increasing end-systolic- and end-diastolic volumes (ESV and EDV) and MFR in these patients measured with Rubidium-82 positron emission tomography computed tomography (⁸²Rb-PET/CT) as a quantitative myocardial perfusion gold-standard.

METHODS

We scanned 151 patients with non-ischemic heart failure with initial left ventricular ejection fraction ≤35% with ⁸²Rb-PET/CT at rest and adenosine-induced stress to obtain MFR and volumes. To account for differences in body surface area (BSA), we used indexed ESV (ESVI): ESV/BSA (ml/m²) and EDV (EDVI). We identified factors associated with MFR using multiple regression analyses.

RESULTS

Median age was 62 years (55-69 years) and 31% were women. Mean MFR was 2.38 (2.24-2.52). MFR decreased significantly with both increasing ESVI (estimate - 3.7%/10 ml/m²; 95% confidence interval [CI] -5.6 to - 1.8; P < 0.001) and increasing EDVI (estimate - 3.5%/10 ml/m²; 95% CI -5.3 to - 1.6; P < 0.001). Results remained significant after multivariable adjustment. Additionally, coronary vascular resistance during stress increased significantly with increasing ESVI (estimate: 3.1 mmHg/(ml/g/min) per (10 ml/m²); 95% CI 2.0 to 4.3; r = 0.41; P < 0.0001) and increasing EDVI (estimate: 2.7 mmHg/(ml/g/min) per (10 ml/m²); 95% CI 1.6 to 3.8; r = 0.37; P < 0.0001).

CONCLUSIONS

Impaired MFR assessed by ⁸²Rb-PET/CT was significantly associated with linear increases in ESVI and EDVI in patients with non-ischemic systolic heart failure. Our findings support that impaired microvascular function may play a role in heart failure development. Clinical trials investigating MFR with regard to treatment responses may elucidate the clinical use of MFR in patients with non-ischemic systolic heart failure.

TRIAL REGISTRATION

Sub study of the randomized clinical trial: A DANish randomized, controlled, multicenter study to assess the efficacy of Implantable cardioverter defibrillator in patients with non-ischemic Systolic Heart failure on mortality (DANISH), ClinicalTrials.gov Identifier: NCT00541268 .

Myocardial perfusion during atrial fibrillation in patients with non-ischaemic systolic heart failure: a cross-sectional study using Rubidium-82 positron emission tomography/computed tomography

Aims

Patients with non-ischaemic systolic heart failure often have reduced myocardial blood flow without significant coronary atherosclerosis. Likewise, patients with atrial fibrillation (AF) have reduced myocardial perfusion during AF compared with sinus rhythm. The aim of this study was to explore whether there is an additive negative effect of AF during scan on the myocardial perfusion in patients with non-ischaemic systolic heart failure.

Methods and results

We included 27 young healthy controls and 114 patients with non-ischaemic systolic heart failure to a Rubidium-82 positron emission tomography/computed tomography perfusion scan (23 with AF during scan). To obtain the myocardial flow reserve (MFR = stress flow/rest flow), patients were scanned at rest and during adenosine-induced stress. Among patients, those with AF were older [years: 73; interquartile range (IQR) 65-78 vs. 67; IQR 60-74; P = 0.03] and more were men (87% vs. 62%; P = 0.02). Distribution of sex in controls did not differ from either patient group. Patients with AF had significantly lower MFR than patients without [MFR: 1.87; 95% confidence interval (CI) 1.58-2.22 vs. 2.50; 95% CI 2.06-2.86; percent difference: -21.5%; P = 0.01]. MFR remained significantly lower in the group with AF (estimate -24.2%; 95% CI -39.6% to -4.8%; P = 0.02) in an adjusted multivariable regression analysis. Further, patients had lower MFR compared with controls: 3.46; 95% CI 3.03-3.94; P < 0.0001. Additionally, coronary vascular resistance was highest in patients with AF and lowest in controls.

Conclusion

Patients with systolic heart failure had lower flow reserve than healthy controls and even lower MFR if they had AF during scan.

Late potentials and their correlation with ventricular structure in patients with ventricular arrhythmias

INTRODUCTION

The presence of late potentials (LP) may indicate a predisposition to ventricular arrhythmias and sudden cardiac death. We investigated the association between presence of LP and structural cardiac anomalies assessed by magnetic resonance (CMR) in patients presenting with ventricular arrhythmias.

METHODS

We included 42 patients admitted with ventricular tachycardia or fibrillation who had undergone both signal-averaged ECG recording and CMR imaging. Clinical data and CMR findings were compared in patients with and without LP.

RESULTS

The majority, 26 (62%) patients, were sudden cardiac death survivors and the remaining 16 (38%) were admitted with ventricular tachycardia. After full diagnostic work-up, the most common diagnoses in the cohort were idiopathic ventricular tachycardia/ventricular fibrillation (25 patients, 60%) or cardiomyopathies (11 patients, 26%). LPs were positive in 29 (69%) when using the revised Task Force criteria. When comparing patients with and without late potentials, there were no significant differences in right ventricular size relative to body surface area (102 mL/m² vs 92 mL/m² ), right ventricular ejection fraction (55% vs 58%), or positive late gadolinium enhancement (29% vs 24%).

CONCLUSIONS

Among patients with malignant arrhythmias, the presence of LP does not distinguish between patients with normal and abnormal RV structure or function on CMR. LP may indicate the presence of an arrhythmic heart disease beyond what can be inferred from CMR. The frequent finding of late potentials indicates that the diagnostic value of LP as an ARVC criteria should be tested in larger studies comparing ARVC patients and controls.

Age and Outcomes of Primary Prevention Implantable Cardioverter-Defibrillators in Patients With Nonischemic Systolic Heart Failure

BACKGROUND

The DANISH study (Danish Study to Assess the Efficacy of ICDs [Implantable Cardioverter Defibrillators] in Patients With Non-Ischemic Systolic Heart Failure on Mortality) did not demonstrate an overall effect on all-cause mortality with ICD implantation. However, the prespecified subgroup analysis suggested a possible age-dependent association between ICD implantation and mortality with survival benefit seen only in the youngest patients. The nature of this relationship between age and outcome of a primary prevention ICD in patients with nonischemic systolic heart failure warrants further investigation.

METHODS

All 1116 patients from the DANISH study were included in this prespecified subgroup analysis. We assessed the relationship between ICD implantation and mortality by age, and an optimal age cutoff was estimated nonparametrically with selection impact curves. Modes of death were divided into sudden cardiac death and nonsudden death and compared between patients younger and older than this age cutoff with the use of χ² analysis.

RESULTS

Median age of the study population was 63 years (range, 21-84 years). There was a linearly decreasing relationship between ICD and mortality with age (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.003-1.06; P=0.03). An optimal age cutoff for ICD implantation was present at ≤70 years. There was an association between reduced all-cause mortality and ICD in patients ≤70 years of age (HR, 0.70; 95% CI, 0.51-0.96; P=0.03) but not in patients >70 years of age (HR, 1.05; 95% CI, 0.68-1.62; P=0.84). For patients ≤70 years old, the sudden cardiac death rate was 1.8 (95% CI, 1.3-2.5) and nonsudden death rate was 2.7 (95% CI, 2.1-3.5) events per 100 patient-years, whereas for patients >70 years old, the sudden cardiac death rate was 1.6 (95% CI, 0.8-3.2) and nonsudden death rate was 5.4 (95% CI, 3.7-7.8) events per 100 patient-years. This difference in modes of death between the 2 age groups was statistically significant (P=0.01).

CONCLUSIONS

In patients with systolic heart failure not caused by ischemic heart disease, the association between the ICD and survival decreased linearly with increasing age. In this study population, an age cutoff for ICD implantation at ≤70 years yielded the highest survival for the population as a whole.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00542945.

Early Gadolinium Enhancement for Determination of Area at Risk: A Preclinical Validation Study

OBJECTIVES

The aim of this study was to determine whether early gadolinium enhancement (EGE) by cardiac magnetic resonance (CMR) in a canine model of reperfused myocardial infarction depicts the area at risk (AAR) as determined by microsphere blood flow analysis.

BACKGROUND

It remains controversial whether only the irreversibly injured myocardium enhances when CMR is performed in the setting of acute myocardial infarction. Recently, EGE has been proposed as a measure of the AAR in acute myocardial infarction because it correlates well with T2-weighted imaging of the AAR, but this still requires pathological validation.

METHODS

Eleven dogs underwent 2 h of coronary artery occlusion and 48 h of reperfusion before imaging at 1.5-T. EGE imaging was performed 3 min after contrast administration with coverage of the entire left ventricle. Late gadolinium enhancement imaging was performed between 10 and 15 min after contrast injection. AAR was defined as myocardium with blood flow <2 SD from remote myocardium determined by microspheres during occlusion. The size of infarction was determined with triphenyltetrazolium chloride.

RESULTS

There was no significant difference in the size of enhancement by EGE compared with the size of AAR by microspheres (44.1 ± 15.8% vs. 42.7 ± 9.2%; p = 0.61), with good correlation (r = 0.88; p < 0.001) and good agreement by Bland-Altman analysis (mean bias 1.4 ± 17.4%). There was no difference in the size of enhancement by EGE compared with enhancement on native T1 and T2 maps. The size of EGE was significantly greater than the infarct by triphenyltetrazolium chloride (44.1 ± 15.8% vs. 20.7 ± 14.4%; p < 0.001) and late gadolinium enhancement (44.1 ± 15.8% vs. 23.5 ± 12.7%; p < 0.001).

CONCLUSIONS

At 3 min post-contrast, EGE correlated well with the AAR by microspheres and CMR and was greater than infarct size. Thus, EGE enhances both reversibly and irreversibly injured myocardium.

Rationale, design, and baseline characteristics of the DANish randomized, controlled, multicenter study to assess the efficacy of Implantable cardioverter defibrillators in patients with non-ischemic Systolic Heart failure on mortality (DANISH)

BACKGROUND

The effect of an implantable cardioverter defibrillator (ICD) in patients with symptomatic systolic heart failure (HF) caused by coronary artery disease is well documented. However, the effect of primary prophylactic ICDs in patients with systolic HF not due to coronary artery disease is much weaker. In addition, HF management has improved, since the landmark ICD trials and a large proportion of patients now receive cardiac resynchronization therapy (CRT) where the effect of ICD treatment is unknown.

METHODS

In the DANISH study, 1,116 patients with symptomatic systolic HF not caused by coronary artery disease have been randomized to receive an ICD or not, in addition to contemporary standard therapy. The primary outcome of the trial is time to all-cause death. Follow-up will continue until June 2016 with a median follow-up period of 5 years. Baseline characteristics show that enrolled patients are treated according to current guidelines. At baseline, 97% of patients received an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, 92% received a β-blocker, 58% a mineralocorticoid receptor antagonist, and 58% were scheduled to receive CRT. Median age was 63 years (range, 21-84 years) at baseline, and 28% were women.

CONCLUSION

DANISH will provide pertinent information about the effect on all-cause mortality of a primary prophylactic ICD in patients with symptomatic systolic HF not caused by coronary artery disease on contemporary standard therapy including CRT.