Risk, Clinical Course, and Outcome of Ischemic Stroke in Patients Hospitalized With COVID-19: A Multicenter Cohort Study.

BACKGROUND AND PURPOSE: The frequency of ischemic stroke in patients with coronavirus disease 2019 (COVID-19) varies in the current literature, and risk factors are unknown. We assessed the incidence, risk factors, and outcomes of acute ischemic stroke in hospitalized patients with COVID-19. METHODS: We included patients with a laboratory-confirmed SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) infection admitted in 16 Dutch hospitals participating in the international CAPACITY-COVID registry between March 1 and August 1, 2020. Patients were screened for the occurrence of acute ischemic stroke. We calculated the cumulative incidence of ischemic stroke and compared risk factors, cardiovascular complications, and in-hospital mortality in patients with and without ischemic stroke. RESULTS: We included 2147 patients with COVID-19, of whom 586 (27.3%) needed treatment at an intensive care unit. Thirty-eight patients (1.8%) had an ischemic stroke. Patients with stroke were older but did not differ in sex or cardiovascular risk factors. Median time between the onset of COVID-19 symptoms and diagnosis of stroke was 2 weeks. The incidence of ischemic stroke was higher among patients who were treated at an intensive care unit (16/586; 2.7% versus nonintensive care unit, 22/1561; 1.4%; P=0.039). Pulmonary embolism was more common in patients with (8/38; 21.1%) than in those without stroke (160/2109; 7.6%; adjusted risk ratio, 2.08 [95% CI, 1.52-2.84]). Twenty-seven patients with ischemic stroke (71.1%) died during admission or were functionally dependent at discharge. Patients with ischemic stroke were at a higher risk of in-hospital mortality (adjusted risk ratio, 1.56 [95% CI, 1.13-2.15]) than patients without stroke. CONCLUSIONS: In this multicenter cohort study, the cumulative incidence of acute ischemic stroke in hospitalized patients with COVID-19 was ≈2%, with a higher risk in patients treated at an intensive care unit. The majority of stroke patients had a poor outcome. The association between ischemic stroke and pulmonary embolism warrants further investigation.

Sex differences in cardiovascular complications and mortality in hospital patients with covid-19: registry based observational study.

Objective: To assess whether the risk of cardiovascular complications of covid-19 differ between the sexes and to determine whether any sex differences in risk are reduced in individuals with pre-existing cardiovascular disease. Design: Registry based observational study. Setting: 74 hospitals across 13 countries (eight European) participating in CAPACITY-COVID (Cardiac complicAtions in Patients With SARS Corona vIrus 2 regisTrY), from March 2020 to May 2021. Participants: All adults (aged ≥18 years), predominantly European, admitted to hospital with highly suspected covid-19 disease or covid-19 disease confirmed by positive laboratory test results (n=11 167 patients). Main outcome measures: Any cardiovascular complication during admission to hospital. Secondary outcomes were in-hospital mortality and individual cardiovascular complications with ≥20 events for each sex. Logistic regression was used to examine sex differences in the risk of cardiovascular outcomes, overall and grouped by pre-existing cardiovascular disease. Results: Of 11 167 adults (median age 68 years, 40% female participants) included, 3423 (36% of whom were female participants) had pre-existing cardiovascular disease. In both sexes, the most common cardiovascular complications were supraventricular tachycardias (4% of female participants, 6% of male participants), pulmonary embolism (3% and 5%), and heart failure (decompensated or de novo) (2% in both sexes). After adjusting for age, ethnic group, pre-existing cardiovascular disease, and risk factors for cardiovascular disease, female individuals were less likely than male individuals to have a cardiovascular complication (odds ratio 0.72, 95% confidence interval 0.64 to 0.80) or die (0.65, 0.59 to 0.72). Differences between the sexes were not modified by pre-existing cardiovascular disease; for the primary outcome, the female-to-male ratio of the odds ratio in those without, compared with those with, pre-existing cardiovascular disease was 0.84 (0.67 to 1.07). Conclusions: In patients admitted to hospital for covid-19, female participants were less likely than male participants to have a cardiovascular complication. The differences between the sexes could not be attributed to the lower prevalence of pre-existing cardiovascular disease in female individuals. The reasons for this advantage in female individuals requires further research.

The impact of pre-existing hypertension and its treatment on outcomes in patients admitted to hospital with COVID-19.

The impact of pre-existing hypertension on outcomes in patients with the novel corona virus (SARS-CoV-2) remains controversial. To address this, we examined the impact of pre-existing hypertension and its treatment on in-hospital mortality in patients admitted to hospital with Covid-19. Using the CAPACITY-COVID patient registry we examined the impact of pre-existing hypertension and guideline-recommended treatments for hypertension on in-hospital mortality in unadjusted and multi-variate-adjusted analyses using logistic regression. Data from 9197 hospitalised patients with Covid-19 (median age 69 [IQR 57-78] years, 60.6% male, n = 5573) was analysed. Of these, 48.3% (n = 4443) had documented pre-existing hypertension. Patients with pre-existing hypertension were older (73 vs. 62 years, p < 0.001) and had twice the occurrence of any cardiac disease (49.3 vs. 21.8%; p < 0.001) when compared to patients without hypertension. The most documented class of anti-hypertensive drugs were angiotensin receptor blockers (ARB) or angiotensin converting enzyme inhibitors (ACEi) (n = 2499, 27.2%). In-hospital mortality occurred in (n = 2020, 22.0%), with more deaths occurring in those with pre-existing hypertension (26.0 vs. 18.2%, p < 0.001). Pre-existing hypertension was associated with in-hospital mortality in unadjusted analyses (OR 1.57, 95% CI 1.42,1.74), no significant association was found following multivariable adjustment for age and other hypertension-related covariates (OR 0.97, 95% CI 0.87,1.10). Use of ACEi or ARB tended to have a protective effect for in-hospital mortality in fully adjusted models (OR 0.88, 95% CI 0.78,0.99). After appropriate adjustment for confounding, pre-existing hypertension, or treatment for hypertension, does not independently confer an increased risk of in-hospital mortality patients hospitalized with Covid-19.

Sex- and age specific association of new-onset atrial fibrillation with in-hospital mortality in hospitalised COVID-19 patients.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a systemic disease with cardiovascular involvement, including cardiac arrhythmias. Notably, new-onset atrial fibrillation (AF) and atrial flutter (AFL) during hospitalisation in COVID-19 patients has been associated with increased mortality. However, how this risk is impacted by age and sex is still poorly understood. METHODS: For this multicentre cohort study, we extracted demographics, medical history, occurrence of electrical disorders and in-hospital mortality from the large international patient registry CAPACITY-COVID. For each electrical disorder, prevalence during hospitalisation was calculated. Subsequently, we analysed the incremental prognostic effect of developing AF/AFL on in-hospital mortality, using multivariable logistic regression analyses, stratified for sex and age. RESULTS: In total, 5782 patients (64% male; median age 67) were included. Of all patients 11.0% (95% CI 10.2-11.8) experienced AF and 1.6% (95% CI 1.3-1.9) experienced AFL during hospitalisation. Ventricular arrhythmias were rare (<0.8% (95% CI 0.6-1.0)) and a conduction disorder was observed in 6.3% (95% CI 5.7-7.0). An event of AF/AFL appeared to occur more often in patients with pre-existing heart failure. After multivariable adjustment for age and sex, new-onset AF/AFL was significantly associated with a poorer prognosis, exemplified by a two- to three-fold increased risk of in-hospital mortality in males aged 60-72 years, whereas this effect was largely attenuated in older male patients and not observed in female patients. CONCLUSION: In this large COVID-19 cohort, new-onset AF/AFL was associated with increased in-hospital mortality, yet this increased risk was restricted to males aged 60-72 years.

Prevalence, pathophysiology, prediction and health-related quality of life of long COVID: study protocol of the longitudinal multiple cohort CORona Follow Up (CORFU) study.

INTRODUCTION: The variety, time patterns and long-term prognosis of persistent COVID-19 symptoms (long COVID-19) in patients who suffered from mild to severe acute COVID-19 are incompletely understood. Cohort studies will be combined to describe the prevalence of long COVID-19 symptoms, and to explore the pathophysiological mechanisms and impact on health-related quality of life. A prediction model for long COVID-19 will be developed and internally validated to guide care in future patients. METHODS AND ANALYSIS: Data from seven COVID-19 cohorts will be aggregated in the longitudinal multiple cohort CORona Follow Up (CORFU) study. CORFU includes Dutch patients who suffered from COVID-19 at home, were hospitalised without or with intensive care unit treatment, needed inpatient or outpatient rehabilitation and controls who did not suffer from COVID-19. Individual cohort study designs were aligned and follow-up has been synchronised. Cohort participants will be followed up for a maximum of 24 months after acute infection. Next to the clinical characteristics measured in individual cohorts, the CORFU questionnaire on long COVID-19 outcomes and determinants will be administered digitally at 3, 6, 12, 18 and 24 months after the infection. The primary outcome is the prevalence of long COVID-19 symptoms up to 2 years after acute infection. Secondary outcomes are health-related quality of life (eg, EQ-5D), physical functioning, and the prevalence of thromboembolic complications, respiratory complications, cardiovascular diseases and endothelial dysfunction. A prediction model and a patient platform prototype will be developed. ETHICS AND DISSEMINATION: Approval was obtained from the medical research ethics committee of Maastricht University Medical Center+ and Maastricht University (METC 2021-2990) and local committees of the participating cohorts. The project is supported by ZonMW and EuroQol Research Foundation. Results will be published in open access peer-reviewed scientific journals and presented at (inter)national conferences. TRIAL REGISTRATION NUMBER: NCT05240742.

Clinical prediction models for mortality in patients with covid-19: external validation and individual participant data meta-analysis.

OBJECTIVE: To externally validate various prognostic models and scoring rules for predicting short term mortality in patients admitted to hospital for covid-19. DESIGN: Two stage individual participant data meta-analysis. SETTING: Secondary and tertiary care. PARTICIPANTS: 46 914 patients across 18 countries, admitted to a hospital with polymerase chain reaction confirmed covid-19 from November 2019 to April 2021. DATA SOURCES: Multiple (clustered) cohorts in Brazil, Belgium, China, Czech Republic, Egypt, France, Iran, Israel, Italy, Mexico, Netherlands, Portugal, Russia, Saudi Arabia, Spain, Sweden, United Kingdom, and United States previously identified by a living systematic review of covid-19 prediction models published in The BMJ, and through PROSPERO, reference checking, and expert knowledge. MODEL SELECTION AND ELIGIBILITY CRITERIA: Prognostic models identified by the living systematic review and through contacting experts. A priori models were excluded that had a high risk of bias in the participant domain of PROBAST (prediction model study risk of bias assessment tool) or for which the applicability was deemed poor. METHODS: Eight prognostic models with diverse predictors were identified and validated. A two stage individual participant data meta-analysis was performed of the estimated model concordance (C) statistic, calibration slope, calibration-in-the-large, and observed to expected ratio (O:E) across the included clusters. MAIN OUTCOME MEASURES: 30 day mortality or in-hospital mortality. RESULTS: Datasets included 27 clusters from 18 different countries and contained data on 46 914patients. The pooled estimates ranged from 0.67 to 0.80 (C statistic), 0.22 to 1.22 (calibration slope), and 0.18 to 2.59 (O:E ratio) and were prone to substantial between study heterogeneity. The 4C Mortality Score by Knight et al (pooled C statistic 0.80, 95% confidence interval 0.75 to 0.84, 95% prediction interval 0.72 to 0.86) and clinical model by Wang et al (0.77, 0.73 to 0.80, 0.63 to 0.87) had the highest discriminative ability. On average, 29% fewer deaths were observed than predicted by the 4C Mortality Score (pooled O:E 0.71, 95% confidence interval 0.45 to 1.11, 95% prediction interval 0.21 to 2.39), 35% fewer than predicted by the Wang clinical model (0.65, 0.52 to 0.82, 0.23 to 1.89), and 4% fewer than predicted by Xie et al's model (0.96, 0.59 to 1.55, 0.21 to 4.28). CONCLUSION: The prognostic value of the included models varied greatly between the data sources. Although the Knight 4C Mortality Score and Wang clinical model appeared most promising, recalibration (intercept and slope updates) is needed before implementation in routine care.

Early- and late anthracycline-induced cardiac dysfunction: echocardiographic characterization and response to heart failure therapy.

BACKGROUND: Anthracycline-induced cardiac dysfunction (ACD) is a notorious side effect of anticancer treatment. It has been described as a phenomenon of a continuous progressive decline of cardiac function, eventually leading to dilated cardiomyopathy (DCM). This progressive nature suggests that patients with a delayed ACD diagnosis have greater compromise of cardiac function and more adverse remodeling, with a poor response to heart failure (HF) treatment. This study aimed to delineate the impact of a delayed ACD diagnosis on echocardiographic characteristics and response to HF treatment. METHODS AND RESULTS: From the population of our cardio-oncology outpatient clinic, 92 ACD patients were included in this study (age 51.6 ± 16.2 years, median cumulative anthracycline dose 329 [200-329] mg/m2), and a median follow-up of 25.0 [9.6-37.2] months after ACD diagnosis. Median time to ACD diagnosis for patients diagnosed early (< 1 year) and late (> 1 year) was 4.0 vs. 47.7 months respectively. There were no echocardiographic differences between patients diagnosed early vs. late (LVEF 43.6 ± 4.9% vs. 43.0 ± 6.2% and iEDV 63.6 vs. 62.9 mL/m2). Eighty-three percent of patients presented with mild LV dysfunction and in 79% the LV was not dilated. Patients diagnosed early were more likely to have (partial) recovery of cardiac function upon HF treatment initiation (p = 0.015). CONCLUSIONS: In the setting of a cardio-oncology outpatient clinic, patients with ACD presented with a hypokinetic non-dilated cardiomyopathy, rather than typical DCM. Timing of ACD diagnosis did not impact HF disease severity. However, in patients receiving an early diagnosis, cardiac function was more likely to recover upon HF treatment.

Cardiac complications in patients hospitalised with COVID-19.

AIMS: To determine the frequency and pattern of cardiac complications in patients hospitalised with coronavirus disease (COVID-19). METHODS AND RESULTS: CAPACITY-COVID is an international patient registry established to determine the role of cardiovascular disease in the COVID-19 pandemic. In this registry, data generated during routine clinical practice are collected in a standardised manner for patients with a (highly suspected) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection requiring hospitalisation. For the current analysis, consecutive patients with laboratory confirmed COVID-19 registered between 28 March and 3 July 2020 were included. Patients were followed for the occurrence of cardiac complications and pulmonary embolism from admission to discharge. In total, 3011 patients were included, of which 1890 (62.8%) were men. The median age was 67 years (interquartile range 56-76); 937 (31.0%) patients had a history of cardiac disease, with pre-existent coronary artery disease being most common (n=463, 15.4%). During hospitalisation, 595 (19.8%) patients died, including 16 patients (2.7%) with cardiac causes. Cardiac complications were diagnosed in 349 (11.6%) patients, with atrial fibrillation (n=142, 4.7%) being most common. The incidence of other cardiac complications was 1.8% for heart failure (n=55), 0.5% for acute coronary syndrome (n=15), 0.5% for ventricular arrhythmia (n=14), 0.1% for bacterial endocarditis (n=4) and myocarditis (n=3), respectively, and 0.03% for pericarditis (n=1). Pulmonary embolism was diagnosed in 198 (6.6%) patients. CONCLUSION: This large study among 3011 hospitalised patients with COVID-19 shows that the incidence of cardiac complications during hospital admission is low, despite a frequent history of cardiovascular disease. Long-term cardiac outcomes and the role of pre-existing cardiovascular disease in COVID-19 outcome warrants further investigation.

Cardiovascular adverse events in patients with non-Hodgkin lymphoma treated with first-line cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP with rituximab (R-CHOP): a systematic review and meta-analysis.

BACKGROUND: Patients treated for non-Hodgkin lymphoma are at risk of cardiovascular adverse events, with the risk of heart failure being particularly high. A regimen of cyclophosphamide, doxorubicin, vincristine, and prednisone, with (R-CHOP) or without (CHOP) rituximab is the standard first-line treatment for aggressive non-Hodgkin lymphoma, and doxorubicin and cyclophosphamide are both associated with left ventricular dysfunction. The aim of this systematic review and meta-analysis was to evaluate the cardiovascular toxicity of this regimen. METHODS: We systematically searched PubMed, EMBASE, and the Cochrane Library from database inception to June 3, 2019, for clinical trials and observational studies in adult patients with non-Hodgkin lymphoma (diffuse large B-cell lymphoma, follicular lymphoma, mantle cell lymphoma, peripheral T-cell lymphoma, and non-Hodgkin lymphoma not otherwise specified) that received first-line treatment with R-CHOP or CHOP. Studies reporting on cardiovascular adverse events and treatment-related cardiovascular mortality were included. Abstracts and articles not written in English were excluded. The main outcomes were the proportion of patients with grade 3-4 cardiovascular adverse events and heart failure. Meta-analyses of one-sample proportions were done in all patients receiving CHOP or R-CHOP. Subgroup analyses on summary estimates were done to determine the effect of number of CHOP or R-CHOP cycles, cycle interval, age, and sex. FINDINGS: Of 2314 identified entries, 137 studies (21 211 patients) published between April, 1984, and June, 2019 were eligible (9541 patients treated with CHOP, 11 293 patients treated with R-CHOP, 377 both regimens used in the study; median follow-up 39·0 months [IQR 25·5-52·8]). From the included studies, 85 subgroups were treated with CHOP, 76 with R-CHOP, and in four studies both CHOP and R-CHOP were used without a subdivision in separate groups. The pooled proportion for grade 3-4 cardiovascular adverse events, based on 77 studies (n=14 351 patients), was 2·35% (95% CI 1·81-2·93; heterogeneity test Q=326·21; τ2=0·0042; I2=71·40%; p<0·0001). For heart failure, the pooled proportion, based on 38 studies (n=5936 patients), was 4·62% (2·25-7·65; heterogeneity test Q=527·33; τ2=0·0384; I2=95·05%; p<0·0001), with a significant increase in reported heart failure from 1·64% (95% CI 0·82-2·65) to 11·72% (3·00-24·53) when cardiac function was evaluated post-chemotherapy (p=0·017). 53 (39%) of 137 studies were rated as having high risk of bias for incomplete outcome data and 54 (39%) for selective reporting. INTERPRETATION: The considerable increase of reported heart failures with cardiac monitoring, indicates that this complication often remains undiagnosed in patients with non-Hodgkin lymphoma who received first-line R-CHOP or CHOP. Our findings are of importance to raise awareness of this complication among clinicians treating patients with non-Hodgkin lymphoma and stresses the need for cardiac monitoring during and after chemotherapy. Prompt initiation of treatment for heart failure in the presymptomatic phase can mitigate the progression to more advanced heart failure stages. FUNDING: None.

Clinical Features and Natural History of PRKAG2 Variant Cardiac Glycogenosis.

BACKGROUND: PRKAG2 gene variants cause a syndrome characterized by cardiomyopathy, conduction disease, and ventricular pre-excitation. Only a small number of cases have been reported to date, and the natural history of the disease is poorly understood. OBJECTIVES: The aim of this study was to describe phenotype and natural history of PRKAG2 variants in a large multicenter European cohort. METHODS: Clinical, electrocardiographic, and echocardiographic data from 90 subjects with PRKAG2 variants (53% men; median age 33 years; interquartile range [IQR]: 15 to 50 years) recruited from 27 centers were retrospectively studied. RESULTS: At first evaluation, 93% of patients were in New York Heart Association functional class I or II. Maximum left ventricular wall thickness was 18 ± 8 mm, and left ventricular ejection fraction was 61 ± 12%. Left ventricular hypertrophy (LVH) was present in 60 subjects (67%) at baseline. Thirty patients (33%) had ventricular pre-excitation or had undergone accessory pathway ablation; 17 (19%) had pacemakers (median age at implantation 36 years; IQR: 27 to 46 years), and 16 (18%) had atrial fibrillation (median age 43 years; IQR: 31 to 54 years). After a median follow-up period of 6 years (IQR: 2.3 to 13.9 years), 71% of subjects had LVH, 29% had AF, 21% required de novo pacemakers (median age at implantation 37 years; IQR: 29 to 48 years), 14% required admission for heart failure, 8% experienced sudden cardiac death or equivalent, 4% required heart transplantation, and 13% died. CONCLUSIONS: PRKAG2 syndrome is a progressive cardiomyopathy characterized by high rates of atrial fibrillation, conduction disease, advanced heart failure, and life-threatening arrhythmias. Classical features of pre-excitation and severe LVH are not uniformly present, and diagnosis should be considered in patients with LVH who develop atrial fibrillation or require permanent pacemakers at a young age.

Cancer Therapy-Related Cardiac Dysfunction of Nonanthracycline Chemotherapeutics: What Is the Evidence?

Cancer therapy-related cardiac dysfunction (CTRCD) is one of the most concerning cardiovascular side effects of cancer treatment. Important reviews within the field of cardio-oncology have described various agents to be associated with a high risk of CTRCD, including mitomycin C, ifosfamide, vincristine, cyclophosphamide, and clofarabine. The aim of this study was to provide insight into the data on which these incidence rates are based. We observed that the reported cardiotoxicity of mitomycin C and ifosfamide is based on studies in which most patients received anthracyclines, complicating the interpretation of their association with CTRCD. The high incidence of vincristine-induced cardiotoxicity is based on an incorrect interpretation of a single study. Incidence rates of clofarabine remain uncertain due to a lack of cardiac screening in clinical trials. The administration of high-dose cyclophosphamide (>1.5 g/m2/day) is associated with a high incidence of CTRCD. Based on our findings, a critical re-evaluation of the cardiotoxicity of these agents is warranted.

Chemotherapy-Related Cardiac Dysfunction: A Systematic Review of Genetic Variants Modulating Individual Risk.

Chemotherapy-related cardiac dysfunction is a significant side effect of anticancer treatment. Risk stratification is based on clinical- and treatment-related risk factors that do not adequately explain individual susceptibility. The addition of genetic variants may improve risk assessment. We conducted a systematic literature search in PubMed and Embase, to identify studies investigating genetic risk factors for chemotherapy-related cardiac dysfunction. Included were articles describing genetic variants in humans altering susceptibility to chemotherapy-related cardiac dysfunction. The validity of identified studies was assessed by 10 criteria, including assessment of population stratification, statistical methodology, and replication of findings. We identified 40 studies: 34 exploring genetic risk factors for anthracycline-induced cardiotoxicity (n=9678) and 6 studies related to trastuzumab-associated cardiotoxicity (n=642). The majority (35/40) of studies had a candidate gene approach, whereas 5 genome-wide association studies have been performed. We identified 25 genetic variants in 20 genes and 2 intergenic variants reported significant at least once. The overall validity of studies was limited, with small cohorts, failure to assess population ancestry and lack of replication. SNPs with the most robust evidence up to this point are CELF4 rs1786814 (sarcomere structure and function), RARG rs2229774 (topoisomerase-2ß expression), SLC28A3 rs7853758 (drug transport), UGT1A6 rs17863783 (drug metabolism), and 1 intergenic variant (rs28714259). Existing evidence supports the hypothesis that genetic variation contributes to chemotherapy-related cardiac dysfunction. Although many variants identified by this systematic review show potential to improve risk stratification, future studies are necessary for validation and assessment of their value in a diagnostic and prognostic setting.

Genetics, Clinical Features, and Long-Term Outcome of Noncompaction Cardiomyopathy.

BACKGROUND: The clinical outcomes of noncompaction cardiomyopathy (NCCM) range from asymptomatic to heart failure, arrhythmias, and sudden cardiac death. Genetics play an important role in NCCM. OBJECTIVES: This study investigated the correlations among genetics, clinical features, and outcomes in adults and children diagnosed with NCCM. METHODS: A retrospective multicenter study from 4 cardiogenetic centers in the Netherlands classified 327 unrelated NCCM patients into 3 categories: 1) genetic, with a mutation in 32% (81 adults; 23 children) of patients; 2) probably genetic, familial cardiomyopathy without a mutation in 16% (45 adults; 8 children) of patients; or 3) sporadic, no family history, without mutation in 52% (149 adults; 21 children) of patients. Clinical features and major adverse cardiac events (MACE) during follow-up were compared across the children and adults. RESULTS: MYH7, MYBPC3, and TTN mutations were the most common mutations (71%) found in genetic NCCM. The risk of having reduced left ventricular (LV) systolic dysfunction was higher for genetic patients compared with the probably genetic and sporadic cases (p = 0.024), with the highest risk in patients with multiple mutations and TTN mutations. Mutations were more frequent in children (p = 0.04) and were associated with MACE (p = 0.025). Adults were more likely to have sporadic NCCM. High risk for cardiac events in children and adults was related to LV systolic dysfunction in mutation carriers, but not in sporadic cases. Patients with MYH7 mutations had low risk for MACE (p = 0.03). CONCLUSIONS: NCCM is a heterogeneous condition, and genetic stratification has a role in clinical care. Distinguishing genetic from nongenetic NCCM complements prediction of outcome and may lead to management and follow-up tailored to genetic status.

A systematic analysis of genetic dilated cardiomyopathy reveals numerous ubiquitously expressed and muscle-specific genes.

AIMS: Despite considerable progress being made in genetic diagnostics for dilated cardiomyopathy (DCM) using panels of the most prevalent genes, the cause remains unsolved in a substantial percentage of patients. We hypothesize that several previously described DCM genes with low or unknown prevalence have been neglected, which, if catalogued, could increase the yield of diagnostic DCM testing. The aim of this study is to catalogue all genetic evidence on DCM comprehensively. METHODS AND RESULTS: We have conducted a systematic literature search on PubMed, Embase, and OMIM to find genes implicated in syndromic and non-syndromic DCM and peripartum cardiomyopathy (PPCM). Our search yielded 110 nuclear protein-coding genes and 24 mitochondrial DNA genes. For nuclear genes, in addition to 42 genes sufficiently reviewed previously (group A), we provide a comprehensive annotation of the level of genetic evidence for the remaining 68 genes (group B). Next, we investigated the tissue specificity of the collected genes using public RNA sequencing data. We show that genes primarily expressed in heart and skeletal muscle are more likely to result in DCM with possible skeletal myopathies, while genes expressed ubiquitously cause DCM with extramuscular manifestations. CONCLUSION: This comprehensive analysis of DCM-associated genes revealed a much higher number of genes than currently screened in diagnostics. Since most genes in group B have only been found mutated in single DCM patients or families, their importance for DCM genetic diagnostics needs to be validated in large cohorts. Targeted sequencing of validated DCM-implicated protein-coding genes and mitochondrial DNA, together with consideration of the tissue specificity of mutated genes, may facilitate further genotype-phenotype studies in DCM.