Prognostic implications of genotype findings in non-ischaemic dilated cardiomyopathy: A network meta-analysis.

AIMS: Evidence on the relative impact of diverse genetic backgrounds associated with non-ischaemic dilated cardiomyopathy (DCM) remains contradictory. This study sought to synthesize the available data regarding long-term outcomes of different gene groups in DCM. METHODS AND RESULTS: Electronic databases were systematically screened to identify studies reporting prognostic data on pre-specified gene groups. Those included pathogenic/likely pathogenic (P/LP) variants, truncating titin variants (TTNtv), lamin A/C variants (LMNA), and desmosomal proteins. Outcomes were divided into composite adverse events (CAEs), malignant ventricular arrhythmic events (MVAEs) and heart failure events (HFEs). A total of 26 studies (n = 7255) were included in the meta-analysis and 6791 patients with genotyped DCM were analysed. Patients with P/LP variants had a higher risk for CAEs (odds ratio [OR] 2.10, 95% confidence interval [CI] 1.67-2.65), MVAEs (OR 1.86, 95% CI 1.52-2.26), and HFEs (OR 2.01, 95% CI 1.08-3.73) than genotype-negative patients. The presence of TTNtv was linked to a higher risk for CAEs (OR 1.78, 95% CI 1.20-2.63), but not MVAEs or HFEs. LMNA and desmosomal groups suffered a higher risk for CAEs, MVAEs, and HFEs compared to non-LMNA and non-desmosomal groups, respectively. When genes were indirectly compared, the presence of LMNA resulted in a more detrimental effect that TTNtv, with respect to all composite outcomes but no significant difference was found between LMNA and desmosomal genes. Desmosomal genes harboured a higher risk for MVAEs compared to TTNtv. CONCLUSIONS: Different genetic substrates associated with DCM result in divergent natural histories. Routine utilization of genetic testing should be employed to refine risk stratification and inform therapeutic strategies in DCM.

Cardiac magnetic resonance for ventricular arrhythmias: a systematic review and meta-analysis.

BACKGROUND: Cardiac magnetic resonance (CMR) allows comprehensive myocardial tissue characterisation, revealing areas of myocardial inflammation or fibrosis that may predispose to ventricular arrhythmias (VAs). With this study, we aimed to estimate the prevalence of structural heart disease (SHD) and decipher the prognostic implications of CMR in selected patients presenting with significant VAs. METHODS: Electronic databases were searched for studies enrolling adult patients that underwent CMR for diagnostic or prognostic purposes in the setting of significant VAs. A random effects model meta-analysis of proportions was performed to estimate the prevalence of SHD. HRs were pooled together in order to evaluate the prognostic value of CMR. RESULTS: The prevalence of SHD was reported in 18 studies. In all-comers with significant VAs, the pooled rate of SHD post-CMR evaluation was 39% (24% in the subgroup of premature ventricular contractions and/or non-sustained ventricular tachycardia vs 63% in the subgroup of more complex VAs). A change in diagnosis after use of CMR ranged from 21% to 66% with a pooled average of 35% (29%-41%). A non-ischaemic cardiomyopathy was the most frequently identified SHD (56%), followed by ischaemic heart disease (21%) and hypertrophic cardiomyopathy (5%). After pooling together data from six studies, we found that the presence of late gadolinium enhancement was associated with increased risk of major adverse outcomes in patients with significant VAs (pooled HR: 1.79; 95% CI 1.33 to 2.42). CONCLUSION: CMR is a valuable tool in the diagnostic and prognostic evaluation of patients with VAs. CMR should be considered early after initial evaluation in the diagnostic algorithm for VAs of unclear aetiology as this strategy may also define prognosis and improve risk stratification.

Periostin is overexpressed, correlated with fibrosis and differs among grades of cardiomyocyte hypertrophy in myectomy tissue of patients with hypertrophic cardiomyopathy.

Periostin, a secreted matricellular protein, has been implicated in cardiac extracellular matrix remodeling and fibrosis. Evidence suggest that periostin stimulates cardiomyocyte hypertrophy. The current study aims to investigate the extent of periostin expression in patients with advanced Hypertrophic Cardiomyopathy (HCM) and its correlation with fibrosis and hallmark histopathological features of the disease. Interventricular septal tissue from thirty-nine HCM patients who underwent myectomy and five controls who died from non-cardiac causes was obtained. Staining with Masson's Trichrome and immunohistochemistry were used to localize fibrosis and periostin respectively. The extent of fibrosis and the expression of periostin were defined as the stained percentage of total tissue area using digital pathology software. Periostin expression was higher in HCM patients compared to controls (p<0.0001), positively correlated with the extent of fibrosis (r = 0.82, p<0.001), positively correlated with maximal interventricular septal thickness (Rho = 0.33, p = 0.04) and negatively correlated with LVEF (r = -0.416, p = 0.009). Periostin was approximately co-localized with fibrosis. Mean periostin expression was lower in patients with mild grade cardiomyocyte hypertrophy compared to those with moderate grade (p = 0.049) and lower in patients with mild grade replacement fibrosis compared to moderate grade (p = 0.036). In conclusion, periostin is overexpressed in advanced HCM, correlated with fibrosis and possibly related to cardiomyocyte hypertrophy.

Apical Hypertrophic Cardiomyopathy: Diagnosis, Natural History, and Management.

Apical hypertrophic cardiomyopathy (ApHCM) represents a rare variant of hypertrophic cardiomyopathy (HCM) with distinct phenotypic characteristics. The prevalence of this variant varies according to each study's geographic region. The leading imaging modality for the diagnosis of ApHCM is echocardiography. Cardiac magnetic resonance, however, is the gold standard for ApHCM diagnosis in case of poor acoustic windows or equivocal echocardiographic findings but also in cases of suspected apical aneurysms. The prognosis of ApHCM was reported to be relatively benign, although more recent studies seem to contradict this, demonstrating similar incidence of adverse events compared with the general HCM population. The aim of this review is to summarize the available evidence for the diagnosis of ApHCM, highlight distinctions in comparison to more frequent forms of HCM with regards to its natural history, prognosis, and management strategies.

Prevalence, characteristics, and natural history of apical phenotype in a large cohort of patients with hypertrophic cardiomyopathy.

BACKGROUND: Apical hypertrophic cardiomyopathy (ApHCM) is a variant of hypertrophic cardiomyopathy (HCM) with distinct imaging and clinical characteristics. Data on the prognosis of this HCM subgroup appear conflicting. Our study aims to clarify the natural history of ApHCM and identify predictors of outcomes. MATERIALS AND METHODS: A total of 856 patients with HCM were retrospectively examined. ApHCM was defined as asymmetric left ventricular hypertrophy confined predominantly at the apex, either isolated (pure ApHCM type) or with co-existent hypertrophy of the interventricular septum (mixed ApHCM). Echocardiographic, clinical, and survival data were compared between individuals with ApHCM and non-ApHCM. RESULTS: A total of 143 (16.7%) patients were diagnosed with ApHCM. Compared with non-ApHCM, subjects with apical HCM were diagnosed at an older age and had better echocardiographic indices and more comorbidities at baseline. Apical aneurysms were more prevalent among the ApHCM phenotype (6.3% vs. 1.7%, p = 0.003). During a mean follow-up of 6 ± 3 years, ApHCM was characterized by lower all-cause, cardiovascular, heart failure-related mortality, and ventricular arrhythmic events compared with non-ApHCM. Multivariate analysis identified atrial fibrillation and HCM risk-sudden cardiac death (SCD) as independent predictors of the composite outcome of overall mortality and hospitalizations for cardiovascular reasons (hazard ratio [HR] 4.3, 95% confidence interval [CI] 1.9-9.5 for atrial fibrillation and HR 1.2, 95% CI 1.02-1.3 for HCM risk-SCD) in ApHCM. CONCLUSIONS: ApHCM exhibited a lower rate of all-cause mortality and arrhythmic events in the middle-aged population of patients with HCM. Atrial fibrillation and HCM risk-sudden cardiac death were independent predictors of a composite of overall mortality and cardiovascular hospitalizations among those with ApHCM.

Left Atrial Myopathy is Associated With Exercise Incapacity and Ventilatory Inefficiency in Hypertrophic Cardiomyopathy.

BACKGROUND: Left atrial (LA) myopathy is an established component of hypertrophic cardiomyopathy (HCM); however, the data about its association with exercise incapacity or ventilatory inefficiency that may be seen in HCM patients are limited. This study aimed to explore the association between LA myopathy, evaluated by echocardiography LA strain, and exercise capacity and ventilatory efficiency, evaluated by cardiopulmonary exercise testing (CPET), in HCM patients. METHODS: This study included 241 consecutive HCM patients (aged 51.2±15.7 years 67.2% male) in sinus rhythm who underwent CPET and transthoracic echocardiography at the same visit. Exercise incapacity (maximal/predicted oxygen consumption [%peakVO2] <80%) and ventilatory inefficiency (ventilation/carbon dioxide output [VE/VCO2] slope >34) were assessed by CPET. Left atrial myopathy was examined by speckle-tracking myocardial deformation parameters: LA reservoir, conduit and booster strain. RESULTS: All three LA strain values were univariate predictors of exercise capacity and ventilatory efficiency. Among them, LA reservoir strain had the higher r correlation coefficient for predicting both %peakVO2 and VE/VCO2 slope. Left atrial reservoir strain, presence of angina and family history of HCM were independent predictors of exercise capacity. Left atrial reservoir strain, male gender and non-sustained ventricular tachycardia were independent predictors of ventilatory efficiency. Left atrial reservoir strain was a significant predictor of %peakVO2<80% with an optimal cut-off value of 27% (sensitivity 87% and specificity 31%) and VE/VCO2>34 with an optimal cut-off value of 18% (sensitivity 71% and specificity 83%). CONCLUSION: Left atrial myopathy, as reflected by the LA strain values, was associated with exercise incapacity and ventilatory inefficiency in HCM individuals. Left atrial reservoir strain was the only common independent predictor of %peakVO2 and VE/VCO2 slope.

Wild-Type Transthyretin Amyloid Cardiomyopathy: The Gordian-Knot of Novel Therapeutic Regimens.

Wild-type TTR amyloidosis (wtATTR) represents a disease difficult to diagnose with poor prognosis. Increased clinical suspicion is key, allowing for timely diagnosis. Until recently, only off-label therapies were available but recent introduction of disease specific therapy has shown potential to alter the natural history of the disease. Tafamidis, the only currently approved drug for the therapy of wtATTR, provided significantly better survival and quality of life. However, not all subgroups of patients derived equal benefit. This, along with the increased cost of treatment raised question on whether treatment should be invariably administered through the wtATTR population. This review aims to summarize current evidence on the natural history and staging systems for wtATTR, as well as available treatment options. Special consideration is given to the selection process of patients who would be expected to gain maximum benefit from tafamidis treatment, based on an ethical and cost-effective point of view.

Real world data on light chain cardiac amyloidosis: Still a delayed diagnosis.

Cardiac amyloidosis (CA) represents a myocardial disorder developed by fibril deposition of a heterogeneous group of misfolding proteins. Despite being rare, a high clinical index of suspicion and novel advanced diagnostic methods seem to facilitate its early recognition. Currently nine types of cardiac amyloidosis have been described with AL and ATTR being the most common. Light chain amyloidosis (AL) is a life-threatening disease, resulting from clonal plasma cells that produce amyloidogenic light chain fragments causing organ damage including the heart. Morbidity and mortality of these patients is strongly associated with the severity of cardiac involvement. Thus, early and precise diagnosis is crucial for prompt treatment initiation. In this study, we retrospectively analyzed data of 36 consecutive patients who were diagnosed with AL amyloidosis and treated in our center over the past 15 years. Heart involvement was present in 33 (92%) of them while 76% had severe cardiac disease as of stage IIIa and IIIb, according to the Mayo2004/European staging system. Almost one third of these patients experienced an early death occurring the first five months of diagnosis. To capture everyday clinical practice, we provide details on clinical presentation, diagnostic challenges, and outcome of these patients.

A novel quantitative method for assessing the therapeutic response to Tafamidis therapy in patients with cardiac TTR amyloidosis. A preliminary report.

OBJECTIVE: Cardiomyopathy is a common manifestation of transthyretin amyloidosis (ATTR), leading to heart failure, associated with high morbidity and mortality. The aim of this study was to investigate the effect of Tafamidis treatment by means of cardiac radiotracer uptake on myocardial scintigraphy. SUBJECTS AND METHODS: Five male patients, mean age 76.2 years, with wild-type ATTR were included in the protocol. Total body scanning using technetium-99m-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) (in four patients) and technetium-99m-hydroxymethylene diphosphonate (99mTc-HMDP) (in one) was performed pre- and one year post-Tafamidis therapy. A novel quantitation method for assessing radiotracer cardiac uptake was employed. The geometric mean was computed for both cardiac and thigh region of interest (ROI) and the heart-to-thigh (HtT) ratio was assessed by dividing the corresponding geometric mean counts. RESULTS: Heart-to-thigh ratio was improved (decreased) in four of the patients receiving Tafamidis, in keeping with lower uptake to the cardiac region. These patients also demonstrated a relatively favorable clinical response to Tafamidis. The patient evaluated by 99mTc-HMDP exhibited minimal HtT ratio reduction and stable clinical and echocardiographic characteristics. CONCLUSION: Sequential HtT ratio measurements could potentially identify patients with a favorable response to Tafamidis treatment at earlier stages, compared to other imaging modalities or serological biomarkers.

Mitral regurgitation impact on left atrial myopathy in hypertrophic cardiomyopathy.

BACKGROUND: Recent studies have shown that mitral regurgitation (MR) represents a major determinant of left atrial (LA) function in patients with heart failure with preserved ejection fraction. The role of MR in determining LA myopathy in hypertrophic cardiomyopathy (HCM) is unknown. The aim of this study was to examine the association of MR with LA myopathy, assessed by LA strain values in HCM patients. METHODS: In total 250 consecutive patients (mean age 51 ± 16 years, 67.2% male) with an established diagnosis of HCM and with sinus rhythm at index echocardiography evaluation were included. LA reservoir, conduit and booster strain were analyzed, besides LA size, left ventricular (LV) systolic and diastolic function. The predictors of LA strain values were identified with linear regression analysis. RESULTS: Significant (more than mild) MR was a significant univariate predictor of all the three LA strain values. In multivariate linear regression analysis, independent predictors of LA reservoir strain were more than mild MR (r = -.23), LV global longitudinal strain (r = -.49), LA volume index (r = -.27) and patient age (r = -.23). Significant MR was also an independent determinant of LA conduit (r = -.17) and booster strain (r = -.12). In patients with LA volume index < 34 ml/m2 more than mild MR was an independent predictor of LA reservoir (r = -.32) and conduit strain (r = -.27), but not LA booster strain. CONCLUSION: Significant MR is associated with LA myopathy independently of the LV diastolic and systolic function and LA size.

Deciphering hypertrophic cardiomyopathy with electrocardiography.

The comprehensive assessment of patients with hypertrophic cardiomyopathy is a complex process, with each step concurrently focusing on confirmation of the diagnosis, differentiation between sarcomeric and non-sarcomeric disease (phenocopy), and prognostication. Novel modalities such as genetic testing and advanced imaging have allowed for substantial advancements in the understanding of this condition and facilitate patient management. However, their availability is at present not universal, and interpretation requires a high level of expertise. In this setting, electrocardiography, a fast and widely available method, still retains a significant role in everyday clinical assessment of this population. In our review, we follow a stepwise approach for the interpretation of each electrocardiographic segment, discussing clinical implications of electrocardiographic patterns in sarcomeric disease, their value in the differential diagnosis from phenocopies, and impact on patient management. Outlining the substantial amount of information to be obtained from a simple tracing, we exhibit how electrocardiography is likely to remain an integral diagnostic tool in the future as well.

Validation of the new American College of Cardiology/American Heart Association Guidelines for the risk stratification of sudden cardiac death in a large Mediterranean cohort with Hypertrophic Cardiomyopathy.

BACKGROUND: The aim of our study was to assess the performance of the new American College of Cardiology (ACC)/American Heart Association (AHA) Guidelines, with respect to sudden cardiac death (SCD) prevention, in comparison with the established risk score of the European Society of Cardiology (hypertrophic cardiomyopathy [HCM] Risk-SCD), in a large Mediterranean cohort of HCM patients. METHODS: The clinical and imaging characteristics of 784 HCM patients (mean age at first evaluation 52 ± 16 years, 67.2% males) were analyzed retrospectively. The sensitivity, specificity, and negative predictive value for SCD events of the presence of ≥1 risk factor for SCD according to the ACC/AHA Guidelines 2020 and of the HCM Risk-SCD≥6% and HCM Risk-SCD≥4% were estimated during follow-up. RESULTS: During follow-up, 47 (6%) patients suffered an SCD event. The presence of ≥1 major risk factor for SCD according to the new ACC/AHA Guidelines had 96% sensitivity (95% CI 85.5-99.5%) with modest specificity of 59% (95% CI 55-62.2%) and negative predictive value of 99.5% (95% CI 98.2-99.9%). On the contrary, HCM- Risk-SCD≥6% had a relatively low sensitivity (32%, 95% CI 19.1-47.1%) and high specificity of 95% (95% CI 93.1-96.4%), whereas, HCM-Risk-SCD≥4% had sensitivity of 60% (95% CI 44-74%) and specificity of 83.9% (95% CI 80-85.6%). Both the HCM Risk-SCD cut-off values demonstrated lower negative predictive value but higher accuracy than the ACC/AHA algorithm for SCD prediction. CONCLUSION: The novel ACC/AHA proposed algorithm identifies most of the patients with an SCD event with the cost of numerous defibrillator implantations. HCM-Risk-SCD demonstrated higher specificity, whereas its sensitivity and negative predictive value are modest.

Routine histopathology of septal myectomy for hypertrophic obstructive cardiomyopathy in a greek cohort.

Hypertrophic cardiomyopathy (HCM) is a diverse inherited disease affecting 1 in 500 individuals irrespective of gender and ethnicity. A fraction of HCM patients will eventually develop drug refractory dynamic obstruction of the left ventricular outflow tract. For such patients, septal myectomy is the procedure of choice to alleviate their symptoms and improve their quality of life. The current histopathological study, the first from the Greek region, aims to examine the hallmark histopathological characteristics of Hypertrophic Obstructive Cardiomyopathy in a population of patients undergoing septal myectomy at a single center over a ten year period. Medical records and histopathology specimens of thirty nine (n=39) patients were evaluated. The sample comprised 22 males (56.4%) and 17 females (43.6%). Mean patient age at myectomy was 53.9±16.7 years, ranging from 12 to 79 years. Maximal IVS thickness on echocardiography was available for 35 patients with a median value of 2.08cm. Peak resting LVOT Pressure Gradient was available for 33 patients with a mean value of 104.88±44.20 mmHg. Central tendency of each histopathological attribute expressed as the median value was: moderate for myocyte hypertrophy, mild for cytoplasmic vacuolization, moderate for subendocardial fibrosis, moderate for interstitial fibrosis, mild for replacement fibrosis, moderate for myofibrillar disarray and mild for capillary stenosis. Myocyte hypertrophy, present in all specimens, was positively correlated with maximal IVS thickness (tau-b=0.43, p=0.002). Replacement fibrosis was positively correlated with the grade of microvascular stenosis (tau-b=0.45, p=0.004). LVEF was negatively correlated with the grade of interstitial fibrosis (tau-b=-0.43, p=0.035) and with the extent of myocardial fiber disarray (tau-b=-0.42, p=0.034). Histopathological attributes were not correlated with patient gender or age thus proving that HCM has a histological phenotype unique to each patient, mainly depending on each specific sarcomeric mutation.

The predictive value of left ventricular and left atrial mechanics for atrial fibrillation and heart failure in hypertrophic cardiomyopathy: a prospective cohort study.

Atrial fibrillation (AF) and heart failure (HF) represent clinical turning points, altering the natural history of HCM and influencing long-term outcome of the disease. The aim of this study was to evaluate the ability of left ventricular (LV) and left atrial (LA) myocardial deformation parameters to predict new-onset AF and HF outcomes in patients with HCM. This was a prospective study that included HCM patients without severe valvular heart disease, prior myocardial infarction or history of AF. The study sample consisted of 250 patients (mean age 50.8 ± 15.8, 67.2% male). Two-dimensional (2D) speckle tracking deformation parameters including global longitudinal strain (GLS), radial strain, circumferential strain, LA reservoir strain (LAεres), LA conduit strain (LAεcon) and LA booster strain(LAεboost) were examined. During a mean follow-up of 2.5 ± 1.2 years, 44 patients developed new-onset AF. All the LV and LA deformation parameters were significant univariate predictors of AF. GLS and LAεres had the highest C statistic among the LV and LA functional indices. In multivariable analysis, only LAεres remained an independent predictor of the arrhythmia (HR 0.91, 95% CI 0.85-0.98, p: 0.008). Similarly, GLS and LAεres had the highest predictive value among the 2D speckle tracking parameters for HF outcomes. LAεres remained an independent predictor after adjusting for significant covariates. GLS and LAεres demonstrated high predictive value for the development of AF and HF in HCM. LAεres was the only independent predictor of both outcomes.Clinical trial registration: ClinicalTrials.gov identifier: NCT04112511.

Prognostic role of left ventricular apical aneurysm in hypertrophic cardiomyopathy: A systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to systematically review and quantitatively synthesize existing evidence about the prognostic value of LV apical aneurysm in patients with HCM. BACKGROUND: Hypertrophic cardiomyopathy (HCM) represents a common inherited heart disease associated with enormous diversity in morphologic expression and clinical course. With the increasing penetration of advanced high resolution cardiovascular imaging into routine HCM practice, a subset of HCM patients with left ventricular (LV) apical aneurysm have become more widely recognized. METHODS: Medline was searched for studies describing the prognostic implication of LV apical aneurysm in patients with HCM. In the main analysis the combined endpoint of major HCM-related outcomes was assessed. Separate analyses for sudden cardiac death (SCD) events and thromboembolic events were also performed. RESULTS: Six studies comprising of 2382 patients met the inclusion criteria. In the pooled analysis, the presence of LV apical aneurysm was significantly associated with major adverse outcomes (pooled OR: 5.13, 95 CI: 2.85 to 9.23, I2:31%), increased risk of SCD arrhythmic events (pooled OR: 4.67, 95% CI: 2.30 to 9.48, I2: 38%) and thromboembolic events (pooled OR: 6.30, 95% CI: 1.52 to 26.19, I2: 66%). CONCLUSIONS: These data demonstrate that LV apical aneurysm in HCM patients is associated with an increased risk for SCD events and thromboembolism. This finding might encourage the inclusion of LV apical aneurysm into the HCM SCD risk stratification algorithm as a novel risk marker that supports consideration for primary prevention implantable cardioverter defibrillator and anticoagulation for stroke prophylaxis.

A simple algorithm for a clinical step-by-step approach in the management of hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease with an autosomal dominant pattern and a reported prevalence of about 0.2%. In this review, we present a simple algorithm for the management of first diagnosed HCM patients. Initially, the clinical examination, medical and detailed family history and the ECG are essential. The etiological diagnosis of left ventricular hypertrophy is important in order to differentiate HCM due to sarcomeric genes mutation from other phenocopies, such as cardiac amyloidosis. The next step consists of the cardiovascular imaging and ambulatory electrocardiography. Cardiopulmonary exercise testing may also be considered if available. All of the above provide evidence for the critical step of the risk stratification of patients for sudden cardiac death. The therapeutic strategy, with respect to obstructive and nonobstructive disease, arrhythmias and end-stage HCM is also described.

Emerging concepts in arrhythmogenic dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) represents one of the primary cardiomyopathies and may lead to heart failure and sudden death. Until recently, ventricular arrhythmias were considered to be a direct consequence of the systolic dysfunction of the left ventricle (LV) and guidelines for implantable cardioverter defibrillator implantation were established on this basis. However, the identification of heritable dilated cardiomyopathy phenotypes that presented with mildly impaired or moderate LV dysfunction, with or without chamber dilatation, and ventricular arrhythmias exceeding the degree of the underlying morphological abnormalities lead to the identification of the arrhythmogenic phenotypes and genotypes of DCM. This subset of DCM patients presents phenotypic and in many cases genotypic overlaps with left dominant arrhythmogenic cardiomyopathy (LDAC). LMNA, SCN5A, FLNC, TTN, and RBM20 are the main genes responsible for arrhythmogenic DCM. Moreover, desmosomal genes such as DSP and other non-desmosomal such as DES and PLN have been associated with both LDAC and arrhythmogenic DCM. The aim of this review is to highlight the importance of genetic profiling among DCM patients with disproportionate arrhythmic burden and the significance of the electrocardiogram, cardiac magnetic resonance, Holter monitoring, detailed family history, and other assays in order to identify red flags for arrhythmogenic DCM and proceed to an early preventive approach for sudden cardiac death. A special consideration was given to the phenotypic and genotypic overlap with LDAC. The role of myocarditis as a common disease expression of LDAC and arrhythmogenic DCM is also analyzed supporting the premise of their phenotypic overlap.