Dilated Cardiomyopathy Patients Research Articles

Predictors of ejection fraction recovery and baseline differences in patients with peripartum cardiomyopathy and dilated cardiomyopathy

Aims: Dilated cardiomyopathy (DCM) and peripartum cardiomyopathy (PPCM) are heart failure conditions with similar clinical, morphological and pathophysiological features but different underlying pathways. In PPCM and DCM patients, improvement in left ventricular ejection fraction (LVEF) varies depending on a number of factors. In this study, we aimed to determine the main differences between DCM and PPCM patients and the predictors of LVEF recovery in these patients. Methods: This cross-sectional, observational study included 33 consecutive female patients, 10 with PPCM and 23 with DCM, attending a tertiary cardiac center between March 2020 and April 2023. We performed a retrospective analysis of some clinical data and LVEF measurements. The main outcome was accepted as EF improvement at a follow-up of at least 12 months. Binary logistic analysis was conducted to assess predictive factors linked to LVEF recovery. This involved using binary logistic regression analysis to figure out odds ratio (OR) and 95% confidence interval (CI). Results: The PPCM group had a higher mean follow-up LVEF and LVEF value increase (p

Seroprevalence of Chagas disease at the Instituto Nacional de Cardiología Ignacio Chávez from 2004 to 2010

Different pathogens can cause dilated cardiomyopathy, one of them is Trypanosoma cruzi protozoan. T.cruzi-chronic infection causes chronic Chagasic cardiomyopathy and affects the sinus node and the conduction systembelow the bundle of His; besides, it shows excellent arrhythmogenic potential because of ventricular arrhythmias. Knowingthe clinical characteristics and performing serological tests to diagnose chronic Chagasic cardiomyopathy is essential. The serological diagnosis for searching the antibodies is based on the phase, which can be a predictor for the development of dilated cardiomyopathy. In this work, the objective was to describe the frequency of dilated cardiomyopathy in patients with T. cruzi positive serology. A total of 961 patients who were medically and clinically diagnosed with dilated cardiomyopathy were studied. Of these, 128 were diagnosed with chronic Chagasic cardiomyopathy and had positive serology for T. cruzi with two serological tests. The clinical findings were obtained from the results of the electrocardiograms and were taken from the patient's clinical histories. In conclusion, complete blockage of the right branch of the bundle of His (44.2%) is one of the primary conduction disorders in the patients studied. Regarding seroprevalence, 14% of patients diagnosed with dilated cardiomyopathy had anti-T. cruzi antibodies.

Personalized care in dilated cardiomyopathy: Rationale and study design of the activeDCM trial.

Dilated cardiomyopathy (DCM) is a leading cause of heart failure, particularly in younger individuals. Low physical strength is a global risk factor for cardiovascular mortality, and physical activity and a healthy lifestyle have been shown to improve outcomes in patients with heart failure. However, inappropriate exercise may increase the risk of arrhythmias in certain individuals with DCM. The determinants for predicting individual risks in this setting are poorly understood, and clinicians are hesitant to recommend sports for cardiomyopathy patients. The activeDCM trial aims to assess the safety and efficacy of a personalized exercise and activity programme for individuals with DCM. The activeDCM trial is a prospective, randomized, interventional trial with a 12month follow-up. Three hundred patients, aged 18-75years with DCM, left ventricular ejection fraction (LVEF)≤50% and New York Heart Association (NYHA) classes I-III, will be enrolled. The intervention includes a personalized exercise and activity programme. The primary outcome is the increase in peak oxygen uptake (VO2max, mL/kg/min) from baseline to 12months. Secondary endpoints include adherence to personalized activity programmes, freedom from clinically relevant arrhythmia, unplanned hospitalization for heart failure and changes in NYHA class, quality of life scores, 6min walk distance, muscular strength, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hsTnT) levels and cardiac function. Advanced research questions include high-density phenome and omics analysis combined with digital biomarkers derived from Apple Watch devices. The activeDCM trial will provide valuable insights into the safety and efficacy of personalized exercise training in DCM patients, inform clinical practice and contribute to the development of heart failure management programmes. The study will generate data on the impact of exercise on various aspects of cardiovascular disease, including genetic, metabolic, phenotypic and longitudinal aspects, facilitating the development of future digital tools and strategies, including the incorporation of smart wearable devices.

Characterization and Long-Term Prognosis of Patients with Different Phenotypes of Dilated Cardiomyopathy.

Long-term prognosis of dilated cardiomyopathy (DCM) in the Chinese population is lacking, and the left ventricular (LV) hypertrabeculation phenotype usually overlaps with DCM. The study aims to investigate whether the presence of the LV hypertrabeculation phenotype confers additional adverse prognostic information for DCM patients. We retrospectively reviewed all DCM patients (≥18 years of age at diagnosis) hospitalized in the Peking Union Medical College Hospital between September 2002 and September 2022. The eligible patients were divided into two groups based on echocardiography at diagnosis: the isolated DCM (n = 353), and DCM with the LV hypertrabeculation phenotype (n = 97). The primary endpoint was major adverse cardiac events (MACEs), and multivariate Cox hazards regression models were used to compare the endpoints between the two groups. During a mean follow-up time of 4.6 years, there was no significant difference in the primary endpoint between the isolated DCM and DCM with the LV hypertrabeculation phenotype (p = 0.19). The risk of MACEs in the first 5 years was significantly higher in DCM with the LV hypertrabeculation phenotype than isolated DCM (adjusted HR [95%CI]: 1.83 [1.21-2.77]) and after 5 years the effect of the LV hypertrabeculation phenotype as a prognostic attenuated. Subgroup analysis found a significant interaction for the incidence of MACEs between sex and DCM subtypes (p for interaction = 0.01). DCM with LV hypertrabeculation phenotypes had a higher early (first 5 years) risk of MACEs. For males, the presence of LV hypertrabeculation phenotypes might be an important clue for identifying high-risk DCM patients.

Description and Prognosis of Patients with Recovered Dilated Cardiomyopathy: A Retrospective Cohort Study.

With the recent advances in the treatment of heart failure (HF), it is intriguing that a very small number of patients with dilated cardiomyopathy (DCM) have been observed as being fully recovered. However, knowledge of the progression and prognosis of patients with recovered DCM remains sparse. Herein, we conducted this study to investigate the clinical characteristics and prognosis of patients with recovered DCM. Consecutive patients with recovered DCM referred to our hospital between March 2009 and May 2021 were included. The recovered DCM patients were categorized into relapse and non-relapse groups. The primary endpoint was all-cause death, and the secondary endpoint was HF re-hospitalization during follow-up. Multivariate analyses were performed to identify predictors of relapse among recovered DCM patients. Kaplan-Meier analyses were used to assess the prognostic significance of relapse. A comparatively large cohort of 122 recovered DCM patients from 10,029 DCM patients was analyzed. During a median follow-up duration of 53.5 months, the relapse rate among recovered DCM patients was 15.6% (19/122). Age (odds ratio, OR 1.079, 95% confidence interval, CI: 1.014-1.148; p = 0.017), systolic blood pressure (SBP) at diagnosis (OR 0.948, 95% CI: 0.908-0.990; p = 0.015) and changes in left ventricular ejection fraction from diagnosis to recovery ( LVEF) (OR 0.898, 95% CI: 0.825-0.978; p = 0.013) were identified as predictors of relapse. Furthermore, among 122 patients, 5 (4.1%) experienced death, and 12 (9.8%) underwent HF re-hospitalization. Four deaths occurred in the relapse group, with one in the non-relapse group. All deaths were attributed to cardiovascular events. The long-term prognosis of the relapse group was significantly worse compared to the non-relapse group by Kaplan-Meier analysis (p 0.001 based on the log-rank test). Multivariate analyses significantly associated relapse with all-cause mortality in recovered DCM patients (hazard ratio, HR 7.738, 95% CI: 1.892-31.636; p = 0.004). Recovered DCM patients are at risk of relapse. Older age, lower SBP, and smaller LVEF were independently associated with relapse in recovered DCM patients. Relapse after recovery was related to an unfavorable long-term prognosis.

Deriving phenotype-representative left ventricular flow patterns by reduced-order modeling and classification

BackgroundExtracting phenotype-representative flow patterns and their associated numerical metrics is a bottleneck in the clinical translation of advanced cardiac flow imaging modalities. We hypothesized that reduced-order models (ROMs) are a suitable strategy for deriving simple and interpretable clinical metrics of intraventricular flow suitable for further assessments. Combined with machine learning (ML) flow-based ROMs could provide new insight to help diagnose and risk-stratify patients. MethodsWe analyzed 2D color-Doppler echocardiograms of 81 non-ischemic dilated cardiomyopathy (DCM) patients, 51 hypertrophic cardiomyopathy (HCM) patients, and 77 normal volunteers (Control). We applied proper orthogonal decomposition (POD) to build patient-specific and cohort-specific ROMs of LV flow. Each ROM aggregates a low number of components representing a spatially dependent velocity map modulated along the cardiac cycle by a time-dependent coefficient. We tested three classifiers using deliberately simple ML analyses of these ROMs with varying supervision levels. In supervised models, hyperparameter grid search was used to derive the ROMs that maximize classification power. The classifiers were blinded to LV chamber geometry and function. We ran vector flow mapping on the color-Doppler sequences to help visualize flow patterns and interpret the ML results. ResultsPOD-based ROMs stably represented each cohort through 10-fold cross-validation. The principal POD mode captured >80 % of the flow kinetic energy (KE) in all cohorts and represented the LV filling/emptying jets. Mode 2 represented the diastolic vortex and its KE contribution ranged from <1 % (HCM) to 13 % (DCM). Semi-unsupervised classification using patient-specific ROMs revealed that the KE ratio of these two principal modes, the vortex-to-jet (V2J) energy ratio, is a simple, interpretable metric that discriminates DCM, HCM, and Control patients. Receiver operating characteristic curves using V2J as classifier had areas under the curve of 0.81, 0.91, and 0.95 for distinguishing HCM vs. Control, DCM vs. Control, and DCM vs. HCM, respectively. ConclusionsModal decomposition of cardiac flow can be used to create ROMs of normal and pathological flow patterns, uncovering simple interpretable flow metrics with power to discriminate disease states, and particularly suitable for further processing using ML.

Unexpected Genetic Twists in Patients with Cardiac Devices.

Objective: To assess the frequency and types of genetic mutations in patients with arrhythmias who underwent cardiac device implantation. Methods: Retrospective observational study, including 38 patients with different arrhythmias and cardiac arrest as a first cardiac event. Treatment modalities encompass pacemakers, transvenous defibrillators, loop recorders, subcutaneous defibrillators, and cardiac resynchronization therapy. All patients underwent genetic testing, using commercially available panels (106-174 genes). Outcome measures include mortality, arrhythmia recurrence, and device-related complications. Results: Clinical parameters revealed a family history of sudden cardiac death in 19 patients (50%), who were predominantly male (58%) and had a mean age of 44.5 years and a mean left ventricle ejection fraction of 40.3%. Genetic testing identified mutations in various genes, predominantly TMEM43 (11%). In two patients (3%) with arrhythmogenic cardiomyopathy, complete subcutaneous defibrillator extraction with de novo transvenous implantable cardioverter-defibrillator implantation was needed. The absence of multiple associations among severe gene mutations was crucial for cardiac resynchronization therapy response. Mortality in this group was around 3% in titin dilated cardiomyopathy patients. Conclusions: Integration of genetic testing into the decision-making process for patients with electronic devices represents a paradigm shift in personalized medicine. By identifying genetic markers associated with arrhythmia susceptibility, heart failure etiology, and cardiac resynchronization therapy response, clinicians can tailor device choices to optimize patient outcomes.

Integrative Analyses of Circulating Proteins and Metabolites Reveal Sex Differences in the Associations with Cardiac Function among DCM Patients.

Dilated cardiomyopathy (DCM) is characterized by reduced left ventricular ejection fraction (LVEF) and left or biventricular dilatation. We evaluated sex-specific associations of circulating proteins and metabolites with structural and functional heart parameters in DCM. Plasma samples (297 men, 71 women) were analyzed for proteins using Olink assays (targeted analysis) or LC-MS/MS (untargeted analysis), and for metabolites using LC MS/MS (Biocrates AbsoluteIDQ p180 Kit). Associations of proteins (n = 571) or metabolites (n = 163) with LVEF, measured left ventricular end diastolic diameter (LVEDDmeasured), and the dilation percentage of LVEDD from the norm (LVEDDacc. to HENRY) were examined in combined and sex-specific regression models. To disclose protein-metabolite relations, correlation analyses were performed. Associations between proteins, metabolites and LVEF were restricted to men, while associations with LVEDD were absent in both sexes. Significant metabolites were validated in a second independent DCM cohort (93 men). Integrative analyses demonstrated close relations between altered proteins and metabolites involved in lipid metabolism, inflammation, and endothelial dysfunction with declining LVEF, with kynurenine as the most prominent finding. In DCM, the loss of cardiac function was reflected by circulating proteins and metabolites with sex-specific differences. Our integrative approach demonstrated that concurrently assessing specific proteins and metabolites might help us to gain insights into the alterations associated with DCM.

Cardiomyocyte-specific Tbk1 deletion aggravated chronic doxorubicin cardiotoxicity via inhibition of mitophagy

Doxorubicin (Dox) use is limited by Dox-induced cardiotoxicity. TANK-blinding kinase 1 (TBK1) is an important kinase involved in the regulation of mitophagy, but the role of TBK1 in cardiomyocytes in chronic Dox-induced cardiomyopathy remains unclear. Cardiomyocyte-specific Tbk1 knockout (Tbk1CKO) mice received Dox (6 mg/kg, injected intraperitoneally) once a week for 4 times, and cardiac assessment was performed 4 weeks after the final Dox injection. Adenoviruses encoding Tbk1 or containing shRNA targeting Tbk1, or a TBK1 phosphorylation inhibitor were used for overexpression or knockdown of Tbk1, or inhibit phosphorylation of TBK1 in isolated primary cardiomyocytes. Our results revealed that moderate Dox challenge decreased TBK1 phosphorylation (with no effect on TBK1 protein levels), resulting in compromised myocardial function, obvious mortality and overt interstitial fibrosis, and the effects were accentuated by Tbk1 deletion. Dox provoked mitochondrial membrane potential collapse and oxidative stress, the effects of which were exacerbated and mitigated by Tbk1 knockdown, specific inhibition of phosphorylation and overexpression, respectively. However, Tbk1 （Ser172A） overexpression did not alleviate these effects. Further scrutiny revealed that TBK1 exerted protective effects on mitochondria via SQSTM1/P62-mediated mitophagy. Tbk1 overexpression mediated cardioprotective effects on Dox-induced cardiotoxicity were cancelled off by Sqstm1/P62 knockdown. Moreover, TBK1-mitophagy-mitochondria cascade was confirmed in heart tissues from dilated cardiomyopathy patients. Taken together, our findings denoted a pivotal role of TBK1 in Dox-induced mitochondrial injury and cardiotoxicity possibly through its phosphorylation and SQSTM1/P62-mediated mitophagy.

Integrated analysis of single-cell RNA sequencing and bulk RNA data reveals gene regulatory networks and targets in dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is a common cause of heart failure, thromboembolism, arrhythmias, and sudden cardiac death. The quality of life and long-term survival rates of patients with dilated DCM have greatly improved in recent decades. Nevertheless, the clinical prognosis for DCM patients remains unfavorable. The primary driving factors underlying the pathogenesis of DCM remain incompletely understood. The present study aimed to identify driving factors underlying the pathogenesis of DCM from the perspective of gene regulatory networks. Single-cell RNA sequencing data and bulk RNA data were obtained from the Gene Expression Omnibus (GEO) database. Differential gene analysis, single-cell genomics analysis, and functional enrichment analysis were conducted using R software. The construction of Gene Regulatory Networks was performed using Python. We used the pySCENIC method to analyze the single-cell data and identified 401 regulons. Through variance decomposition, we selected 19 regulons that showed significant responsiveness to DCM. Next, we employed the ssGSEA method to assess regulons in two bulk RNA datasets. Significant statistical differences were observed in 9 and 13 regulons in each dataset. By intersecting these differentiated regulons and identifying shared targets that appeared at least twice, we successfully pinpointed three differentially expressed targets across both datasets. In this study, we assessed and identified 19 gene regulatory networks that were responsive to the disease. Furthermore, we validated these networks using two bulk RNA datasets of DCM. The elucidation of dysregulated regulons and targets (CDKN1A, SAT1, ZFP36) enhances the molecular understanding of DCM, aiding in the development of tailored therapies for patients.

Impact of Concurrent Ischaemic Stroke on Unfavourable Outcomes in Men and Women with Dilated Cardiomyopathy.

Growing evidence suggests that concurrent ischaemic stroke (IS) exacerbates the prognosis of patients with dilated cardiomyopathy (DCM) and that this effect may be further influenced by sex. However, the exact effect of sex remains unclear. This study aimed to explore the effects of the relevant risk factors on the prognosis of patients with DCM and concurrent IS. Considering the sex differences in DCM, this study further investigated the impact of concurrent IS on the prognosis of men and women with DCM. A total of 632 patients with DCM enrolled between 2016 and 2021 were included in this study. Clinical data were obtained from medical records, and all participants were followed up in the outpatient clinic or by telephone for at least 1 year. A Cox proportional hazards model and Kaplan-Meier curves were used to evaluate the effects of concurrent IS on the prognosis of patients with DCM. Patients with DCM complicated with IS (DCM-IS) had significantly lower cumulative survival rates than patients with DCM without IS (non-IS) (74.6% vs. 84.2%, 2 = 6.85, p = 0.009). Additionally, IS was associated with greater risks of death and heart transplantation (HTx) in men (75.8% vs. 85.1%, 2 = 5.02, p = 0.025), but not in women (71.0% vs. 81.5%, 2 = 1.91, p = 0.167). This large-scale multicentre prospective cohort study demonstrated a poorer prognosis in patients with concurrent DCM and IS, particularly among men. Patients with DCM should not be overlooked in IS screening, emphasis should be placed on the occurrence of IS in patients with DCM. Early and proactive secondary prevention of cerebrovascular diseases might improve the prognosis of DCM patients. More intervention studies focusing on men with DCM complicated with IS should be prioritised.

Therapeutic Inhibition of LincRNA-p21 Protects Against Cardiac Hypertrophy.

Cardiac hypertrophy is an adaptive response to pressure overload aimed at maintaining cardiac function. However, prolonged hypertrophy significantly increases the risk of maladaptive cardiac remodeling and heart failure. Recent studies have implicated long noncoding RNAs in cardiac hypertrophy and cardiomyopathy, but their significance and mechanism(s) of action are not well understood. We measured lincRNA-p21 RNA and H3K27ac levels in the hearts of dilated cardiomyopathy patients. We assessed the functional role of lincRNA-p21 in basal and surgical pressure-overload conditions using loss-of-function mice. Genome-wide transcriptome analysis revealed dysregulated genes and pathways. We labeled proteins in proximity to full-length lincRNA-p21 using a novel BioID2-based system. We immunoprecipitated lincRNA-p21-interacting proteins and performed cell fractionation, ChIP-seq (chromatin immunoprecipitation followed by sequencing), and co-immunoprecipitation to investigate molecular interactions and underlying mechanisms. We used GapmeR antisense oligonucleotides to evaluate the therapeutic potential of lincRNA-p21 inhibition in cardiac hypertrophy and associated heart failure. lincRNA-p21 was induced in mice and humans with cardiomyopathy. Global and cardiac-specific lincRNA-p21 knockout significantly suppressed pressure overload-induced ventricular wall thickening, stress marker elevation, and deterioration of cardiac function. Genome-wide transcriptome analysis and transcriptional network analysis revealed that lincRNA-p21 acts in trans to stimulate the NFAT/MEF2 (nuclear factor of activated T cells/myocyte enhancer factor-2) pathway. Mechanistically, lincRNA-p21 is bound to the scaffold protein KAP1 (KRAB-associated protein-1). lincRNA-p21 cardiac-specific knockout suppressed stress-induced nuclear accumulation of KAP1, and KAP1 knockdown attenuated cardiac hypertrophy and NFAT activation. KAP1 positively regulates pathological hypertrophy by physically interacting with NFATC4 to promote the overactive status of NFAT/MEF2 signaling. GapmeR antisense oligonucleotide depletion of lincRNA-p21 similarly inhibited cardiac hypertrophy and adverse remodeling, highlighting the therapeutic potential of inhibiting lincRNA-p21. These findings advance our understanding of the functional significance of stress-induced long noncoding RNA in cardiac hypertrophy and demonstrate the potential of lincRNA-p21 as a novel therapeutic target for cardiac hypertrophy and subsequent heart failure.

TRIM35 Monoubiquitinates H2B in Cardiac Cells, Implications for Heart Failure.

The tumor suppressor and proapoptotic transcription factor P53 is induced (and activated) in several forms of heart failure, including cardiotoxicity and dilated cardiomyopathy; however, the precise mechanism that coordinates its induction with accessibility to its transcriptional promoter sites remains unresolved, especially in the setting of mature terminally differentiated (nonreplicative) cardiomyocytes. Male and female control or TRIM35 (tripartite motif containing 35) overexpression adolescent (aged 1-3 months) and adult (aged 4-6 months) transgenic mice were used for all in vivo experiments. Primary adolescent or adult mouse cardiomyocytes were isolated from control or TRIM35 overexpression transgenic mice for all in vitro experiments. Adenovirus or small-interfering RNA was used for all molecular experiments to overexpress or knockdown, respectively, target genes in primary mouse cardiomyocytes. Patient dilated cardiomyopathy or nonfailing left ventricle samples were used for translational and mechanistic insight. Chromatin immunoprecipitation and DNA sequencing or quantitative real-time polymerase chain reaction (qPCR) was used to assess P53 binding to its transcriptional promoter targets, and RNA sequencing was used to identify disease-specific signaling pathways. Here, we show that E3-ubiquitin ligase TRIM35 can directly monoubiquitinate lysine-120 (K120) on histone 2B in postnatal mature cardiomyocytes. This epigenetic modification was sufficient to promote chromatin remodeling, accessibility of P53 to its transcriptional promoter targets, and elongation of its transcribed mRNA. We found that increased P53 transcriptional activity (in cardiomyocyte-specific Trim35 overexpression transgenic mice) was sufficient to initiate heart failure and these molecular findings were recapitulated in nonischemic human LV dilated cardiomyopathy samples. These findings suggest that TRIM35 and the K120Ub-histone 2B epigenetic modification are molecular features of cardiomyocytes that can collectively predict dilated cardiomyopathy pathogenesis.

Impact of Functional Mitral Regurgitation on Left Ventricular Strain in Nonischemic Dilated Cardiomyopathy Patients with Type 2 Mellitus Diabetes: A Magnetic Resonance Feature Tracking Study

BackgroundThe impact of functional mitral regurgitation and type 2 mellitus diabetes (T2DM) on left ventricular (LV) strain in nonischemic dilated cardiomyopathy (NIDCM) patients remains unclear.PurposeTo evaluate the impact of mitral regurgitation severity on LV strain, and explore additive effect of T2DM on LV function across varying mitral regurgitation severity levels in NIDCM patients.Study TypeRetrospective.Population352 NIDCM (T2DM−) patients (49.1 ± 14.6 years, 67% male) (207, 85, and 60 no/mild, moderate, and severe mitral regurgitation) and 96 NIDCM (T2DM+) patients (55.2 ± 12.4 years, 77% male) (47, 30, and 19 no/mild, moderate, and severe mitral regurgitation).Field Strength/Sequence3.0 T/balanced steady‐state free precession sequence.AssessmentLV geometric parameters and strain were measured and compared among groups. Determinants of LV strain were investigated.Statistical TestStudent's t‐test, Mann–Whitney U test, one‐way ANOVA, Kruskal‐Wallis test, univariable and multivariable linear regression. P &lt; 0.05 was considered statistically significant.ResultsLV GLPS and longitudinal PDSR decreased gradually with increasing mitral regurgitation severity in NIDCM patients with T2DM(GLPS: −5.7% ± 2.1% vs. −4.3% ± 1.6% vs. −2.6% ± 1.3%; longitudinal PDSR:0.5 ± 0.2 sec−1 vs. 0.4 ± 0.2 sec−1 vs. 0.3 ± 0.1 sec−1). NIDCM (T2DM+) demonstrated decreased GCPS and GLPS in the no/mild subgroup, reduced LV GCPS, GLPS, and longitudinal PDSR in the moderate subgroup, and reduced GRPS, GCPS, GLPS, and longitudinal PDSR in the severe subgroup compared with NIDCM (T2DM−) patients. Multivariable regression analysis identified that mitral regurgitation severity (β = −0.13, 0.15, and 0.25 for GRPS, GCPS, and GLPS) and the presence of T2DM (β = 0.14 and 0.13 for GCPS and GLPS) were independent determinants of LV strains in NIDCM patients.Data ConclusionIncreased mitral regurgitation severity is associated with reduced LV strains in NIDCM patients with T2DM. The presence of T2DM exacerbated the decline of LV function across various mitral regurgitation levels in NIDCM patients, resulting in reduced LV strains.Level of Evidence3.Technical EfficacyStage 3.

Establishment of a human induced pluripotent stem cell line from a patient with dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is one of the main causes of sudden cardiac death and heart failure and is the leading indication for cardiac transplantation worldwide. Mutations in dozens of cardiac genes have been connected to the development of DCM including the Troponin T2 gene (TNNT2). Here, we generated a human induced pluripotent stem cells (hiPSCs) from a DCM patient with a familial history that carries a missense mutation in TNNT2. The hiPSCs show typical morphology of pluripotent stem cells, expression of pluripotency markers, normal karyotype, and in vitro capacity to differentiate into all three germ layers.

Speckle Tracking Echocardiography in Patients with Non-Ischemic Dilated Cardiomyopathy Who Undergo Cardiac Resynchronization Therapy: A Narrative Review.

Non-ischemic dilated cardiomyopathy (DCM) represents a significant cause of heart failure, defined as the presence of left ventricular (LV) dilatation and systolic dysfunction unexplained solely by abnormal loading conditions or coronary artery disease. Cardiac resynchronization therapy (CRT) has emerged as a cornerstone in the management of heart failure, particularly in patients with DCM. However, identifying patients who will benefit the most from CRT remains challenging. Speckle tracking echocardiography (STE) has garnered attention as a non-invasive imaging modality that allows for the quantitative assessment of myocardial mechanics, offering insights into LV function beyond traditional echocardiographic parameters. This comprehensive review explores the role of STE in guiding patient selection and optimizing outcomes in CRT for DCM. By assessing parameters such as LV strain, strain rate, and dyssynchrony, STE enables a more precise evaluation of myocardial function and mechanical dyssynchrony, aiding in the identification of patients who are most likely to benefit from CRT. Furthermore, STE provides valuable prognostic information and facilitates post-CRT optimization by guiding lead placement and assessing response to therapy. Through an integration of STE with CRT, clinicians can enhance patient selection, improve procedural success rates, and ultimately, optimize clinical outcomes in patients with DCM. This review underscores the pivotal role of STE in advancing personalized management strategies for DCM patients undergoing CRT.

Predictors of long-term success after successful explantation of continuous flow left ventricular assist device support.

Predictors and evaluations of continuous flow left ventricular assist device (cf-LVAD) explantation in recovered patients remains under discussion due to lack of evidence on long-term safety and efficacy. This study summarized our experiences regarding cf-LVAD explantation in non-ischaemic dilated cardiomyopathy patients and estimated a predictor for sufficient myocardial recovery allowing LVAD explant. We retrospectively identified 135 adult patients with cf-LVAD therapy as bridge to heart transplant due to non-ischaemic dilated cardiomyopathy. Of those, 13 patients underwent device explantation (recovery group) after myocardial recovery. 12 (92%) of the explanted patients were evaluated using our weaning protocol, and underwent surgical explantation. Meanwhile, the remaining 122 continued with cf-LVAD therapy (non- recovery group). Multivariate logistic regression analysis revealed time interval between the first heart failure event and cf-LVAD implantation as an independent predictor for successful explantation. The optimal time interval cutoff value to predict cf-LVAD explantation was 7 months, with a sensitivity of 91.0% and specificity of 84.6%. Echocardiography in patients with successful cf-LVAD explantation showed significant improvement of left ventricular function and dimensions at six months postoperatively. The 13 explanted patients are currently alive at a median of 30 (IQR; 18-58) months after explantation. The survival rate free from rehospitalization due to heart failure following explantation was 100%. Left ventricular function and remodelling after explantation were also preserved. In non-ischaemic dilated cardiomyopathy patients with a short interval between the first heart failure event and cf-LVAD therapy, left ventricular myocardium may recover in an early phase after device implantation.

Homozygous TNNI3 frameshift variant in a consanguineous family with lethal infantile dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) is characterized by dilatation of the left ventricle, systolic dysfunction, and normal or reduced thickness of the left ventricular wall. It is a leading cause of heart failure and cardiac death at a young age. Cases with neonatal onset DCM were correlated with severe clinical presentation and poor prognosis. A monogenic molecular etiology accounts for nearly half of cases. Here, we report a family with three deceased offspring at the age of 1 year old. The autopsy of the first deceased infant revealed a DCM. The second infant presented a DCM phenotype with a severely reduced Left Ventricular Ejection Fraction (LVEF) of 10%. Similarly, the third infant showed a severe DCM phenotype with LVEF of 30% as well, in addition to eccentric mitral insufficiency. Exome sequencing was performed for the trio (the second deceased infant and her parents). Data analysis following the autosomal dominant and recessive patterns of inheritance was carried out along with a mitochondrial pathways-based analysis. We identified a homozygous frameshift variant in the TNNI3 gene (c.204delG; p.(Arg69AlafsTer8)). This variant has been recently reported in the ClinVar database in association with cardiac phenotypes as pathogenic or likely pathogenic and classified as pathogenic according to ACMG. Genetic counseling was provided for the family and a prenatal diagnosis of choronic villus was proposed in the absence of pre-implantation genetic diagnosis possibilities. Our study expands the case series of early-onset DCM patients with a protein-truncating variant in the TNNI3 gene by reporting three affected infant siblings.

Impacts of DCM-linked gating pore currents on the electrophysiological characteristics of hiPSC-CM monolayers

BackgroundVariants of the SCN5A gene, which encodes the NaV1.5 cardiac sodium channel, have been linked to arrhythmic disorders associated with dilated cardiomyopathy (DCM). However, the precise pathological mechanisms remain elusive. The present study aimed to elucidate the pathophysiological consequences of the DCM-linked Nav1.5/R219H variant, which is known to generate a gating pore current, using patient-specific human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) cultured in monolayers. MethodsVentricular- and atrial-like hiPSC-CM monolayers were generated from DCM patients carrying the R219H SCN5A variant as well as from healthy control individuals. CRISPR-corrected hiPSC-CMs served as isogenic controls. Simultaneous optical mapping of action potentials (APs) and calcium transients (CaTs) was employed to measure conduction velocities (CVs) and AP durations (APDs) and served as markers of electrical excitability. Calcium handling was evaluated by assessing CaT uptake (half-time to peak), recapture (tau of decay), and durations (TD50 and TD80). A multi-electrode array (MEA) analysis was conducted on hiPSC-CM monolayers to measure field potential (FP) parameters, including corrected Fridericia FP durations (FPDc). ResultsOur results revealed that CVs were significantly reduced by more than 50 % in both ventricular- and atrial-like hiPSC-CM monolayers carrying the R219H variant compared to the control group. APDs were also prolonged in the R219H group compared to the control and CRISPR-corrected groups. CaT uptake, reuptake, and duration were also markedly delayed in the R219H group compared to the control and CRISPR-corrected groups in both the ventricular- and the atrial-like hiPSC-CM monolayers. Lastly, the MEA data revealed a notably prolonged FPDc in the ventricular- and atrial-like hiPSC-CMs carrying the R219H variant compared to the control and isogenic control groups. ConclusionsThese findings highlight the impact of the gating pore current on AP propagation and calcium homeostasis within a functional syncytium environment and offer valuable insights into the potential mechanisms underlying DCM pathophysiology.

Absence of late gadolinium enhancement and outcomes of cardiac resynchronization therapy in non-ischemic dilated cardiomyopathy

Abstract Background Among patients with non-ischemic dilated cardiomyopathy (DCM) with indication for cardiac resynchronization therapy (CRT), there are no clear recommendations about who should receive a CRT-defibrillator (CRT-D) and who should have CRT-pacemaker (CRT-P). Absence of late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) has a high negative predictive value for ventricular arrhythmias (VA) and sudden death (SD) in DCM and is a predictor of reverse remodelling in several scenarios. Purpose To evaluate the association between absence of LGE and VA/SD or echocardiographic response to CRT in DCM patients treated with CRT. Methods Multicenter retrospective observational cohort study including consecutive DCM patients with de-novo CRT implant and with available CMR. The primary endpoints were: 1) a combined arrhythmic endpoint including appropriate defibrillator therapies, sustained VA and sudden death. 2) echocardiographic response to CRT, intended as an increase ≥10% in left ventricular ejection fraction (LVEF). Results We included 167 patients, 55% males, with median QRS duration of 160ms and median LVEF of 25%. LGE was present in 46% of cases (LGE+). A CRT-D was implanted in 73% of patients. Median follow-up was 63 months. Of note, among patients without LGE (LGE-) we did not record any event of the combined arrhythmic endpoint. The cumulative incidence of the arrhythmic endpoint was significantly higher in LGE+ than in LGE- patients (25% vs 0%, p&amp;lt;0.001) and LGE was an independent predictor of this endpoint (adjusted HR 42, p&amp;lt;0.001). The proportion of responders to CRT was significantly higher in LGE- than in LGE+ cases (81% vs 53%, p&amp;lt;0.001); absence of LGE was the strongest predictor of echocardiographic response to CRT at multivariate analysis (adjusted OR 4.1, p=0.001). Super-responders (i.e. those with LVEF≥50% at follow-up) were also more frequent among LGE- than LGE+ patients (46% vs 21%, p=0.001) and absence of LGE was an independent predictor of LVEF normalization (HR 2.6, p=0.03). Conclusions Among DCM patients who receive CRT, those without LGE have an extremely low (or null in this case) arrhythmic risk and, at the same time, they have a high probability of echocardiographic response to CRT. Thus, LGE- patients could be ideal candidates for CRT-P instead of CRT-D.