Subtype Of Cardiomyopathy Research Articles

SÍNDROME DE YAMAGUCHI – RELATO DE CASO

Yamaguchi Syndrome is a subtype of hypertrophic cardiomyopathy characterized by hypertrophy in the left ventricular apex. It is a rare syndrome in Brazil, being commonly found in Japan. It has a wide clinical spectrum, ranging from asymptomatic patients to sudden death. Diagnosis is elucidated through changes in the electrocardiogram and echocardiogram, with cardiac magnetic resonance imaging being the most specific exam. The initial treatment is clinical, and may be extended to surgical procedures if refractory to drug management. This study aims to present a clinical case of Yamaguchi Syndrome in a patient in the state of Ceará, emphasizing the importance of including the syndrome in the differential diagnosis of symptoms with chest pain, dyspnea and palpitations.

Relationship between obesity and hypertrophic or dilated cardiomyopathy: the role of sex

Abstract Background Evidence suggests an association between obesity and the risk for cardiomyopathy development, however robust evidence is still lacking. In this study we sought to explore the relationship of obesity with hypertrophic (HCM) and dilated cardiomyopathy (DCM) and possible interactions with sex using large scale epidemiological real-world data. Methods and Results We analyzed data from the Nationwide Inpatient Sample (NIS) of U.S. hospitalizations for the years 2015-2019. There were a total of n=46,934 admissions with a diagnosis of HCM and n=170,924 with DCM. There was a significant interaction between cardiomyopathies’ diagnosis with sex and age subgroups; the rates of both DCM and HCM increased with age (p<0.001 for both); DCM diagnosis was significantly higher in males compared with females (0.85% vs. 0.35%, p<0.001). After adjustment for age, sex, race, and presence of arterial hypertension there was a significant stepwise positive association between obesity and the population rates of both cardiomyopathy subtypes. For hospitalized patients with a body mass index (BMI) ≥30kg/m2 there was an odds ratio (OR) of 1.68 (95%CI: 1.55-1.81, p<0.001) for HCM andOR=1.82 (95%CI: 1.79-1.84, p<0.001) for DCM. More importantly, the positive relationship between a cardiomyopathy diagnosis (HCM or DCM) with increasing BMI was driven by the male sex (p<0.001 for both) and it was non-significant in females. Conclusions The findings from this nationwide observational analysis support a sexual dimorphism in the relationship between obesity and hypertrophic or dilated cardiomyopathy, which should be further investigated.Cardiomyopathy-obesity

Exploring novel MYH7 gene variants using in silico analyses in Korean patients with cardiomyopathy

BackgroundPathogenic variants of MYH7, which encodes the beta-myosin heavy chain protein, are major causes of dilated and hypertrophic cardiomyopathy.MethodsIn this study, we used whole-genome sequencing data to identify MYH7 variants in 397 patients with various cardiomyopathy subtypes who were participating in the National Project of Bio Big Data pilot study in Korea. We also performed in silico analyses to predict the pathogenicity of the novel variants, comparing them to known pathogenic missense variants.ResultsWe identified 27 MYH7 variants in 41 unrelated patients with cardiomyopathy, consisting of 20 previously known pathogenic/likely pathogenic variants, 2 variants of uncertain significance, and 5 novel variants. Notably, the pathogenic variants predominantly clustered within the myosin motor domain of MYH7. We confirmed that the novel identified variants could be pathogenic, as indicated by high prediction scores in the in silico analyses, including SIFT, Mutation Assessor, PROVEAN, PolyPhen-2, CADD, REVEL, MetaLR, MetaRNN, and MetaSVM. Furthermore, we assessed their damaging effects on protein dynamics and stability using DynaMut2 and Missense3D tools.ConclusionsOverall, our study identified the distribution of MYH7 variants among patients with cardiomyopathy in Korea, offering new insights for improved diagnosis by enriching the data on the pathogenicity of novel variants using in silico tools and evaluating the function and structural stability of the MYH7 protein.

Relationship between obesity and hypertrophic or dilated cardiomyopathy: The role of sex.

Evidence suggests an association between obesity and the risk for cardiomyopathy development; however, robust evidence is still lacking. In this study we sought to explore the relationship of obesity with hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM) and possible interactions with sex using large-scale epidemiological real-world data. We analysed data from the Nationwide Inpatient Sample of US hospitalisations for the years 2015-2019. There were a total of 46 934 admissions with diagnosis of HCM and 170 924 with DCM. There was a significant interaction between cardiomyopathies' diagnosis with sex and age subgroups; the rates of both DCM and HCM increased with age (p < .001 for both); DCM diagnosis was significantly higher in males compared with females (0.85% vs. 0.35%, p < .001). After adjustment for age, sex, race and presence of arterial hypertension there was a significant stepwise positive association between obesity and the population rates of both cardiomyopathy subtypes. For hospitalised patients with a body mass index (BMI) ≥30 kg/m2 there was an odds ratio (OR) of 1.68 (95% CI: 1.55-1.81, p < .001) for HCM and OR = 1.82 (95% CI: 1.79-1.84, p < .001) for DCM. More importantly, the positive relationship between a cardiomyopathy diagnosis (HCM or DCM) with increasing BMI was driven by the male sex (p < .001 for both) and it was non-significant in females. The findings from this nationwide observational analysis support a sexual dimorphism in the relationship between obesity and HCM or DCM, which should be further investigated.

Unraveling the genetic tapestry of pediatric sarcomeric cardiomyopathies and masquerading phenocopies in Jordan

Pediatric cardiomyopathies are mostly attributed to variants in sarcomere-related genes. Unfortunately, the genetic architecture of pediatric cardiomyopathies has never been previously studied in Jordan. We sought to uncover the genetic landscape of 14 patients from nine families with several subtypes of pediatric cardiomyopathies in Jordan using Exome sequencing (ES). Our investigation identified pathogenic and likely pathogenic variants in seven out of nine families (77.8%), clustering in sarcomere-related genes. Surprisingly, phenocopies of sarcomere-related hypertrophic cardiomyopathies were evident in probands with glycogen storage disorder and mitochondrial-related disease. Our study underscored the significance of streamlining ES or expanding cardiomyopathy-related gene panels to identify plausible phenocopies of sarcomere-related cardiomyopathies. Our findings also pointed out the need for genetic testing in patients with cardiomyopathy and their at-risk family members. This can potentially lead to better management strategies, enabling early interventions, and ultimately enhancing their prognosis. Finally, our findings provide an initial contribution to the currently absent knowledge about the molecular underpinnings of cardiomyopathies in Jordan.

Epicardial catheter ablation of ventricular tachycardia in patients of acm - from a university hospital report in switzerland

Abstract Background Arrhythmogenic left ventricular cardiomyopathy (ALVC) as a subtype of arrhythmogenic cardiomyopathy (ACM) is increasingly being recognized. Cardiac magnetic resonance (CMR) has emerged as the primary imaging modality for the diagnosis of ACM. In patients with right-dominant ACM (ARVC) and recurrent sustained ventricular tachycardia (VT), endocardial +/-epicardial ablation yields good clinical outcomes in the long-term. However, studies on VT ablation in ACM with LV involvement are scarce. Purpose We sought to investigate clinical outcomes of VT ablation in ACM patients with LV involvement. Methods The study included patients from the Zurich ACM Registry who met 2020 "Padua Criteria" for ACM and underwent VT ablation between January 2018 and July 2023. Epicardial ablation was performed in patients with recurrent sustained VT despite endocardial ablation, those lacking and endocardial substrate or if the ECG of the VT / substrate on CMR was suggestive of an epicardial origin. Catheter ablation was guided by activation/entrainment mapping for mappable VT, and pace mapping/voltage mapping during sinus rhythm for unmappable VT. Consecutive follow-up of all patients was performed according to our protocol. Results Twenty-one ACM patients underwent n=24 VT ablation procedures. Of those 20 patients, 6 patients (30%) had LV involvement on CMR. Eight (33%) patients underwent epicardial +/- endocardial ablation. Among patients receiving epicardial ablation, 3 patients (38%) had LV involvement. These three underwent a single ablation procedure, which was epicardial only. Total follow-up was 30 months (range 4-43). Three-month sustained VT/VF recurrence rates were 12% in the ACM group with LV involvement vs 25% in ACM without LV involvement. All patients with sustained VT/VF recurrence underwent repeat ablation via an epicardial approach within 3 months and were free of sustained VT/VF thereafter during a median follow-up of 12 months. One-year recurrence rate did not differ between ACM patients with LV involvement vs. without LV involvement (7.7% vs 8.3%, P＝0.117). Seven out of eight epicardial ablations achieved freedom from VT/VF after one-year follow-up. One ARVC patient with previous endocardial ablation had recurrent VT one month after epicardial ablation, which was free of VT after Flecainide combined with beta-blocker. No significant differences were found in the use of beta-blockers and antiarrhythmic drugs between both groups (ACM with LV involvement vs. without LV involvement) at baseline and during one-year follow-up. Conclusions Single or adjuvant epicardial substrate ablation of VT in arrhythmogenic cardiomyopathy is promising in terms of postprocedural VT free survival, especially in patients with left ventricular involvement demonstrated by CMR.Figure 1Figure 2

(764) - Genetic Signatures in Heart Transplant and LVAD Patients: Unraveling Their Association with Hypertrophic and Dilated Cardiomyopathy Subtypes

(764) - Genetic Signatures in Heart Transplant and LVAD Patients: Unraveling Their Association with Hypertrophic and Dilated Cardiomyopathy Subtypes

Genotype-Phenotype Insights of Inherited Cardiomyopathies-A Review.

Background: Cardiomyopathies (CMs) represent a heterogeneous group of primary myocardial diseases characterized by structural and functional abnormalities. They represent one of the leading causes of cardiac transplantations and cardiac death in young individuals. Clinically they vary from asymptomatic to symptomatic heart failure, with a high risk of sudden cardiac death due to malignant arrhythmias. With the increasing availability of genetic testing, a significant number of affected people are found to have an underlying genetic etiology. However, the awareness of the benefits of incorporating genetic test results into the care of these patients is relatively low. Aim: The focus of this review is to summarize the current basis of genetic CMs, including the most encountered genes associated with the main types of cardiomyopathies: hypertrophic, dilated, restrictive arrhythmogenic, and non-compaction. Materials and Methods: For this narrative review, we performed a search of multiple electronic databases, to select and evaluate relevant manuscripts. Results: Advances in genetic diagnosis led to better diagnosis precision and prognosis prediction, especially with regard to the risk of developing arrhythmias in certain subtypes of cardiomyopathies. Conclusions: Implementing the genomic information to benefit future patient care, better risk stratification and management, promises a better future for genotype-based treatment.

Cardiomyopathies in children and adolescents: aetiology, management, and outcomes in the European Society of Cardiology EURObservational Research Programme Cardiomyopathy and Myocarditis Registry.

Childhood-onset cardiomyopathies are rare and poorly characterized. This study examined the baseline characteristics and 1-year follow-up of children with cardiomyopathy in the first European Cardiomyopathy Registry. Prospective data were collected on individuals aged 1-<18 years enrolled in the European Society of Cardiology EURObservational Research Programme Cardiomyopathy and Myocarditis long-term registry (June 2014-December 2016). A total of 633 individuals aged ≤18 years with hypertrophic [HCM; n = 388 (61.3%)], dilated [DCM; n = 206 (32.5%)], restrictive [RCM; n = 28 (4.4%)], and arrhythmogenic right ventricular cardiomyopathy [ARVC; n = 11 (1.7%)] were enrolled by 23 referral centres in 14 countries. Median age at diagnosis was 4.0 [interquartile range (IQR) 0-10] years, and there was a male predominance [n = 372 (58.8%)] across all subtypes, with the exception of DCM diagnosed <10 years of age; 621 (98.1%) patients were receiving cardiac medication and 80 (12.6%) had an implantable cardioverter-defibrillator. A total of 253 patients (253/535, 47.3%) had familial disease. Genetic testing was performed in 414 (67.8%) patients with a pathogenic or likely pathogenic variant reported in 250 (60.4%). Rare disease phenocopies were reported in 177 patients (28.0%) and were most frequent in patients under 10 years [142 (30.9%) vs. 35 (19.6%); P = .003]. Over a median follow-up of 12.5 months (IQR 11.3-15.3 months), 18 patients (3.3%) died [HCM n = 9 (2.6%), DCM n = 5 (3.0%), RCM n = 4 (16.0%)]. Heart failure events were most frequent in RCM patients (36.0%). The findings confirm the heterogeneous aetiology of childhood cardiomyopathies and show a high frequency of familial disease. Outcomes differed by cardiomyopathy subtype, highlighting a need for disease-specific evaluation and treatment.

Prevalence, sex differences, and implications of pulmonary hypertension in patients with apical hypertrophic cardiomyopathy.

Apical hypertrophic cardiomyopathy (ApHCM) is a subtype of hypertrophic cardiomyopathy (HCM) that affects up to 25% of Asian patients and is not as well understood in non-Asian patients. Although ApHCM has been considered a more "benign" variant, it is associated with increased risk of atrial and ventricular arrhythmias, apical thrombi, stroke, and progressive heart failure. The occurrence of pulmonary hypertension (PH) in ApHCM, due to elevated pressures on the left side of the heart, has been documented. However, the exact prevalence of PH in ApHCM and sex differences remain uncertain. We sought to evaluate the prevalence, risk associations, and sex differences in elevated pulmonary pressures in the largest cohort of patients with ApHCM at a single tertiary center. A total of 542 patients diagnosed with ApHCM were identified using ICD codes and clinical notes searches, confirmed by cross-referencing with cardiac MRI reports extracted through Natural Language Processing and through manual evaluation of patient charts and imaging records. In 414 patients, echocardiogram measurements of pulmonary artery systolic pressure (PASP) were obtained at the time of diagnosis. The mean age was 59.4 ± 16.6 years, with 181 (44%) being females. The mean PASP was 38 ± 12 mmHg in females vs. 33 ± 9 mmHg in males (p < 0.0001). PH as defined by a PASP value of > 36 mmHg was present in 140/414 (34%) patients, with a predominance in females [79/181 (44%)] vs. males [61/233 (26%), p < 0.0001]. Female sex, atrial fibrillation, diagnosis of congestive heart failure, and elevated filling pressures on echocardiogram remained significantly associated with PH (PASP > 36 mmHg) in multivariable modeling. PH, when present, was independently associated with mortality [hazard ratio 1.63, 95% CI (1.05-2.53), p = 0.028] and symptoms [odds ratio 2.28 (1.40, 3.71), p < 0.001]. PH was present in 34% of patients with ApHCM at diagnosis, with female sex predominance. PH in ApHCM was associated with symptoms and increased mortality.

Human Genetics of Cardiomyopathies.

The identification of a disease-causing variant in a patient diagnosed with cardiomyopathy allows for presymptomatic testing in at risk relatives. Carriers of a pathogenic variant can subsequently be screened at intervals by a cardiologist to assess the risk for potentially life-threatening arrhythmias which can be life-saving. In addition, gene-specific recommendations for risk stratification and disease specific pharmacological options for therapy are beginning to emerge. The large variability in disease penetrance, symptoms, and prognosis, and in some families even in cardiomyopathy subtype, makes genetic counseling both of great importance and complicated.

Characterization of atrial cardiomyopathy subtypes - A cellular electrophysiological comparison and evaluation of appropriate treatment options

Abstract Background Atrial fibrillation occurs in the context of atrial remodeling processes which are the result of an underlying atrial cardiomyopathy (AC). Insufficient understanding of the pathophysiological mechanisms behind AC contributes significantly to the fact that current clinical strategies for the treatment of atrial fibrillation are often ineffective. A systematic investigation of these cellular remodeling processes in the context of the various cardiac diseases underlying AC is still missing. Purpose The aim of this study was to characterize different subtypes of AC associated with common cardiac disease entities by systematic cellular electrophysiological characterization of the atria in combination with molecular and structural investigations. Methods For a comprehensive analysis of the molecular changes associated with AC, we characterized several mouse models of common heart diseases, including models for dilated cardiomyopathy (DCM), HFpEF, mitral regurgitation and immune checkpoint inhibitor (ICI-)mediated myocarditis. Patch clamp experiments were performed on isolated atrial cardiomyocytes to study atrial action potentials (aAP) and different ion currents contributing to the aAP. The cellular electrophysiological parameters of the different models were correlated to clinical parameters (ecg, echocardiography of the atria) of the mouse models and with data from RNA sequencing of the mice’ atria. Results Patch clamp measurements performed on isolated left and right atrial cardiomyocytes revealed distinct differences among the examined models. In all pathophysiological models, the aAP was significantly shorter than in the corresponding wild type mice. The different ion current components we measured various changes in potassium, sodium and calcium currents. The repolarizing TASK-1 potassium current was significantly increased in all models. The DCM model caused by an R636Q mutation in the RBM20 gene showed the most severe changes in cellular electrophysiology. Considering the detected atrial changes, we investigated the effects of SGLTi on atrial cardiomyocytes of the different models. When elevated concentrations of dapa-, empa- and sotagliflozin were administrated on atrial cardiomyocytes, a class-I-antiarrhythmic effect with reduced aAP inducibility and changes in the aAP duration could be observed. Conclusion Characterization of murine models of cardiac disease with respect to classification of AC subtypes revealed various electrical remodeling processes at the level of ion currents involved in aAP formation. A potent inductor of atrial proarrhythmogenity in the AC subtypes was an aAP shortening caused by an increase in repolarizing potassium currents, mediated especially by TASK-1. The most severe electrical remodeling in atria cardiomyocytes was observed in the RBM20-mutant model (DCM). SGLTi exhibit anti-arrhythmic effects in different murine disease models and may provide future treatment options for patients with AC.

Diagnostic Yield of Exome Sequencing in Pediatric Cardiomyopathy

To assess the diagnostic yield of exome sequencing (ES) in pediatric cardiomyopathy. A single-institution, retrospective chart review of 91 patients with pediatric cardiomyopathy was performed. While pediatric cardiomyopathy is often genetic in nature, no genetic test is recommended as standard of care. All our patients were diagnosed with cardiomyopathy and evaluated by a medical geneticist between January 2010 through September 2022. Demographic information and clinical data were abstracted. Of 91 patients with pediatric cardiomyopathy, 36 (39.6%) received a diagnosis by ES. Twenty-two (61.1%) of these diagnoses would have been missed on cardiac multigene panel testing. The diagnostic yield for cardiomyopathy presenting under 1year of age was 38.3%, while the yield for patients over 1year of age was 41.9%. ES has a high diagnostic yield in pediatric cardiomyopathy compared with a gene panel. Over 60% of patients with diagnosis by ES would not have received their molecular genetic diagnosis if only multigene panel testing was sent. Diagnostic yield did not vary significantly between the subtypes of cardiomyopathy and patient age groups, highlighting the likely clinical utility of ES for all pediatric cardiomyopathy patients.

Value of cardiac magnetic resonance on the risk stratification of cardiomyopathies.

Cardiomyopathies represent a diverse group of heart muscle diseases with varying etiologies, presenting a diagnostic challenge due to their heterogeneous manifestations. Regular evaluation using cardiac imaging techniques is imperative as symptoms can evolve over time. These imaging approaches are pivotal for accurate diagnosis, treatment planning, and optimizing prognostic outcomes. Among these, cardiovascular magnetic resonance (CMR) stands out for its ability to provide precise anatomical and functional assessments. This manuscript explores the significant contributions of CMR in the diagnosis and management of patients with cardiomyopathies, with special attention to risk stratification. CMR's high spatial resolution and tissue characterization capabilities enable early detection and differentiation of various cardiomyopathy subtypes. Additionally, it offers valuable insights into myocardial fibrosis, tissue viability, and left ventricular function, crucial parameters for risk stratification and predicting adverse cardiac events. By integrating CMR into clinical practice, clinicians can tailor patient-specific treatment plans, implement timely interventions, and optimize long-term prognosis. The non-invasive nature of CMR reduces the need for invasive procedures, minimizing patient discomfort. This review highlights the vital role of CMR in monitoring disease progression, guiding treatment decisions, and identifying potential complications in patients with cardiomyopathies. The utilization of CMR has significantly advanced our understanding and management of these complex cardiac conditions, leading to improved patient outcomes and a more personalized approach to care.

Clinical features, etiology, and survival in patients with restrictive cardiomyopathy: A single-center experience.

Numerous prognostic factors have been proposed for cardiac amyloidosis (CA). The knowledge about other subtypes of restrictive cardiomyopathy (RCM) is scant. This study aimed to elucidate the etiology and prognostic factors of RCM as well as assess cardiac biomarkers: high-sensitive troponin T (hs-TnT), growth differentiation factor-15 (GDF-15), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and soluble suppression of tumorigenicity 2, as mortality predictors in RCM. We enrolled 36 RCM patients in our tertiary cardiac department. All patients were screened for CA. Genetic testing was performed in 17 patients without CA. Pathogenic or likely pathogenic gene variants were found in 86% of patients, including 5 novel variants. Twenty patients died, and 4 had a heart transplantation during the study. Median overall survival was 29 months (8-55). The univariate Cox models analysis indicated that systolic and diastolic blood pressure, GDF-15, hs-TnT, NT-proBNP, left ventricular stroke volume, the ratio of the transmitral early peak velocity (E) estimated by pulsed wave Doppler over the early mitral annulus velocity (e'), tricuspid annulus plane systolic excursion, early tricuspid valve annular systolic velocity, the presence of pulmonary hypertension, and pericardial effusion influenced survival (P <0.05). A worse prognosis was observed in patients with GDF-15 >1316 pg/ml, hs-TnT >42 ng/l, NT-proBNP >3383 pg/ml, and pericardial effusion >3.5 mm (Kaplan-Meier analysis, log-rank test, P <0.001). Genetic testing should be considered in every RCM patient where light-chain amyloidosis has been excluded. Survival remains poor regardless of etiology. Increased concentrations of GDF-15, hs-TNT, NT-proBNP, and pericardial effusion are associated with worse prognosis. Further studies are warranted.

The burden of splice-disrupting variants in inherited heart disease and unexplained sudden cardiac death

There is an incomplete understanding of the burden of splice-disrupting variants in definitively associated inherited heart disease genes and whether these genes can amplify from blood RNA to support functional confirmation of splicing outcomes. We performed burden testing of rare splice-disrupting variants in people with inherited heart disease and sudden unexplained death compared to 125,748 population controls. ClinGen definitively disease-associated inherited heart disease genes were amplified using RNA extracted from fresh blood, derived cardiomyocytes, and myectomy tissue. Variants were functionally assessed and classified for pathogenicity. We found 88 in silico-predicted splice-disrupting variants in 128 out of 1242 (10.3%) unrelated participants. There was an excess burden of splice-disrupting variants in PKP2 (5.9%), FLNC (2.7%), TTN (2.8%), MYBPC3 (8.2%) and MYH7 (1.3%), in distinct cardiomyopathy subtypes, and KCNQ1 (3.6%) in long QT syndrome. Blood RNA supported the amplification of 21 out of 31 definitive disease-associated inherited heart disease genes. Our functional studies confirmed altered splicing in six variants. Eleven variants of uncertain significance were reclassified as likely pathogenic based on functional studies and six were used for cascade genetic testing in 12 family members. Our study highlights that splice-disrupting variants are a significant cause of inherited heart disease, and that analysis of blood RNA confirms splicing outcomes and supports variant pathogenicity classification.

Improved Diagnostic Criteria for Apical Hypertrophic Cardiomyopathy

BackgroundThere is no acceptable maximum wall thickness (MWT) threshold for diagnosing apical hypertrophic cardiomyopathy (ApHCM), with guidelines referring to ≥15 mm MWT for all hypertrophic cardiomyopathy subtypes. A normal myocardium naturally tapers apically; a fixed diagnostic threshold fails to account for this. Using cardiac magnetic resonance, “relative” ApHCM has been described with typical electrocardiographic features, loss of apical tapering, and cavity obliteration but also with MWT <15 mm. ObjectivesThe authors aimed to define normal apical wall thickness thresholds in healthy subjects and use these to accurately identify ApHCM. MethodsThe following healthy subjects were recruited: healthy UK Biobank imaging substudy subjects (n = 4,112) and an independent healthy volunteer group (n = 489). A clinically defined disease population of 104 ApHCM subjects was enrolled, with 72 overt (MWT ≥15 mm) and 32 relative (MWT <15 mm but typical electrocardiographic/imaging findings) ApHCM subjects. Cardiac magnetic resonance–derived MWT was measured in 16 segments using a published clinically validated machine learning algorithm. Segmental normal reference ranges were created and indexed (for age, sex, and body surface area), and diagnostic performance was assessed. ResultsIn healthy cohorts, there was no clinically significant age-related difference for apical wall thickness. There were sex-related differences, but these were not clinically significant after indexing to body surface area. Therefore, segmental reference ranges for apical hypertrophy required indexing to body surface area only (not age or sex). The upper limit of normal (the largest of the 4 apical segments measured) corresponded to a maximum apical MWT in healthy subjects of 5.2 to 5.6 mm/m2 with an accuracy of 0.94 (the unindexed equivalent being 11 mm). This threshold was categorized as abnormal in 99% (71/72) of overt ApHCM patients, 78% (25/32) of relative ApHCM patients, 3% (122/4,112) of UK Biobank subjects, and 3% (13/489) of healthy volunteers. ConclusionsPer-segment indexed apical wall thickness thresholds are highly accurate for detecting apical hypertrophy, providing confidence to the reader to diagnose ApHCM in those not reaching current internationally recognized criteria.

Cardiac Magnetic Resonance in Patients with Suspected Tachycardia-Induced Cardiomyopathy: The Impact of Late Gadolinium Enhancement and Epicardial Fat Tissue.

Tachycardia-induced cardiomyopathy (TIC) is a reversible subtype of dilated cardiomyopathy (DCM) resulting from sustained supraventricular or ventricular tachycardia and diagnosed by the normalization of left ventricular ejection fraction (LVEF) after stable sinus rhythm restoration. The aim of this study was to determine the contribution of cardiac magnetic resonance (CMR) to the differential diagnosis of TIC and DCM with persistent atrial arrythmias in patients hospitalized for the first time with heart failure (HF) with reduced LVEF of nonischemic origin. A total of 29 patients (age: 58.2 ± 16.9 years; males: 65.5%; average EF: 37.0 ± 9.5%) with persistent atrial tachyarrhythmia and first decompensation of HF without known coronary artery diseases were included in this study. The patients successfully underwent cardioversion and were observed for 30 days. The study population was divided into groups of responders (TIC patients; N = 16), which implies achieving FF > 50% or its increase > 10% in 30 days of TIC, and non-responders (N = 13). The increase in left ventricle (LV) volumes measured using CMR was significantly higher in the non-responder group when compared with the responders (114.8 mL ± 25.1 vs. 68.1 mL ± 10.5, respectively, p < 0.05). Non-responders also demonstrated decreased interventricular septum thickness (9.1 ± 0.8 vs.11.5 ± 1.3, respectively, p < 0.05). Late gadolinium enhancement (LGE) was observed in 12 patients (41.4%). The prevalence of LGE was increased in the non-responder group (25.0% vs. 65.1%, respectively, p = 0.046). Notably, a septal mid-wall LGE pattern was found exclusively in the non-responders. Epicardial adipose tissue thickness was decreased in the non-responder group versus the TIC patients. Conclusion: Patients with TIC were found to have smaller atrial and ventricular dimensions in comparison to patients with DCM. In addition, LGE was more common in DCM patients.

Machine learning modeling identifies hypertrophic cardiomyopathy subtypes with genetic signature.

Previous studies have revealed that patients with hypertrophic cardiomyopathy (HCM) exhibit differences in symptom severity and prognosis, indicating potential HCM subtypes among these patients. Here, 793 patients with HCM were recruited at an average follow-up of 32.78 ± 27.58 months to identify potential HCM subtypes by performing consensus clustering on the basis of their echocardiography features. Furthermore, we proposed a systematic method for illustrating the relationship between the phenotype and genotype of each HCM subtype by using machine learning modeling and interactome network detection techniques based on whole-exome sequencing data. Another independent cohort that consisted of 414 patients with HCM was recruited to replicate the findings. Consequently, two subtypes characterized by different clinical outcomes were identified in HCM. Patients with subtype 2 presented asymmetric septal hypertrophy associated with a stable course, while those with subtype 1 displayed left ventricular systolic dysfunction and aggressive progression. Machine learning modeling based on personal whole-exome data identified 46 genes with mutation burden that could accurately predict subtype propensities. Furthermore, the patients in another cohort predicted as subtype 1 by the 46-gene model presented increased left ventricular end-diastolic diameter and reduced left ventricular ejection fraction. By employing echocardiography and genetic screening for the 46 genes, HCM can be classified into two subtypes with distinct clinical outcomes.

The Relevance of Preventive Implantable Cardioverter-Defibrillators (ICDs) in Non-Ischemic Cardiomyopathy in the Presence of Effective Quadruple Therapy for Heart Failure: A Review of Contemporary Medical Literature.

Cardiomyopathy is a disease of the cardiomyocytes that affects their structural function, leading to heart failure (HF). Non-ischemic cardiomyopathy (NICM) includes a subtype of dilated cardiomyopathy (DCM), restrictive cardiomyopathy (RCM), and hypertrophic cardiomyopathy (HCM). These types of cardiomyopathies have no coronary artery vessel involvement. The most common cause of NICM is DCM. In the ischemic cardiomyopathy (ICM) subtype, the utilization of implantable cardioverter-defibrillators (ICDs) has been effective in the prevention of sudden cardiac death (SCD). However, the relevance of ICDs in patients with NICM having an ejection fraction (EF) ≤35%, who are also receiving effective quadruple therapy (i.e., angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARB), beta-blockers, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter-2 (SGLT2) inhibitors)for HF has been a topic of debate.The purpose of this review is to analyze the benefits of preventive ICDs in NICM patients on adequate quadruple therapy for HF. The current guidelines recommend ICD implantation in patients with NICM who have a left ventricular ejection fraction of ≤35%, come under the New York Heart Association (NYHA) class II or III, andare in sinus rhythm with optimal medical therapy. The evidence supporting this recommendation islimited. Numerous clinical studies and meta-analyses have been conducted to look into this issue. While some have discovered a substantial decrease in mortality with the implantation of an ICD in patients with NICM, others have not found significant changes.Thereby, further investigations are required to define the function of ICDs in this population.