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<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.

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.

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

Ageing of substantia nigra in humans: cell loss may be compensated by hypertrophy

In a stereological study of the human substantia nigra (SN), the total number of melanin-positive and melanin-negative neurones from 28 male subjects aged 19-92 years was estimated using a uniform sampling design and optical disectors. There was a significant decrease in the total number of melanin-positive neurones as a function of age (r(2)=0.18, residual-CV=0.35, 2P=0.032). Using the rotator method, the size distribution of the melanin-positive neurones was estimated and showed a significant difference in mean cell volume of melanin-positive neurones between the seven youngest (21,077 microm(3)) and the seven oldest individuals (32,011 microm(3)), 2P=0.022. Using a combination of the total number of melanin-positive neurones and their size distribution, the total perikaryon volume of melanin-positive neurones could be estimated and showed no decrease with increasing age (r(2)=0.01, residual-CV=0.41, 2P=0.62). Age-related decline in dopamine-transporter neurones within the SN might explain the occurrence of extrapyramidal symptoms in many elderly individuals. Although age-related cell hypertrophy is usually considered to be an indication of cell degeneration or necrosis, this might not always be the case. The fact that motor symptoms, although present in many of the elderly, are of a limited nature despite the high percentage of lost neurones could be due to a compensatory increase in the cell body of dopamine-producing SN neurones. Thus, the total amount of cell substance capable of producing the essential transmitters might not be reduced to a critically low level as a result of ageing.

No deficit in total number of neurons in the prefrontal cortex in schizophrenics

The prefrontal cortex (PFC), defined as the cortical region which has the major reciprocal connections with the mediodorsal thalamic nucleus (MD), has often been implicated in schizophrenia. Morphometric studies have shown altered neuronal density and structure in parts of the PFC in schizophrenic brains. In addition, the MD and nucleus accumbens have shown a significant deficit in total neuron number. The purpose of the present study was to estimate the total neuron number in the PFC in schizophrenics and controls. Using a stereological design, the PFC was studied in eight brains from schizophrenic patients and 10 age-matched control brains. The bilateral average total number of neurons in the PFC was estimated to be 2.76 x 10(9) (CV=S.D./mean=0.15) in the schizophrenic brains whereas that of controls was a non-significantly different value of 3.11 x 10(9) (CV=0.22; P=0.23). Furthermore, no significant differences were found between the two groups in neuronal density (P=0.10) or volume of the PFC (P=0.49). It is of course possible that a neuronal deficit, which cannot be revealed when estimating the total global number of neurons in the whole PFC, might exist in a subregion of the PFC. In conclusion, uniform loss of neuronal soma in the PFC does not appear to constitute the neural substrate of the pathological process in schizophrenia.

Stereological studies of the schizophrenic brain

Stereological studies have contributed with important results to the understanding of brain abnormalities in schizophrenia. The data obtained from stereological studies of brains from schizophrenic patients, including studies of the thalamus, hippocampus, and cortex, are discussed and suggest a central role of the thalamic nuclei in the etiology of the disease. The basic stereological tools are presented and possible biases in quantification studies are discussed.