Insights into mildly dilated cardiomyopathy: temporal evolution and long-term prognosis

The "Padua classification" of cardiomyopathies: Combining pathobiological basis and morpho-functional remodeling

Over the last 20 years, the scientific progresses in molecular biology and genetics in combination with the increasing use in the clinical setting of contrast-enhanced cardiac magnetic resonance (CMR) for morpho-functional imaging and structural myocardial tissue characterization have provided important new insights into our understanding of the distinctive aspects of cardiomyopathy, regarding both the genetic and biologic background and the clinical phenotypic features. This has led to the need of an appropriate revision and upgrading of current nosographic framework and pathobiological categorization of heart muscle disorders. This article proposes a new definition and classification of cardiomyopathies that rely on the combination of the distinctive pathobiological basis (genetics, molecular biology and pathology) and the clinical phenotypic pattern (morpho-functional and structural features), leading to the proposal of three different disease categories, each of either genetic or non-genetic etiology and characterized by a combined designation based on both "anatomic" and "functional" features, i.e., hypertrophic/restrictive (H/RC), dilated/hypokinetic (D/HC) and scarring/arrhythmogenic cardiomyopathy (S/AC). The clinical application of the newly proposed classification approach in the real-world practice appears crucial to design a targeted clinical management and evaluation of outcomes of affected patients. Although current treatment of cardiomyopathies is largely palliative and based on drugs, catheter ablation, device or surgical interventions aimed to prevent and manage heart failure and malignant arrhythmias, better knowledge of basic mechanisms involved in the onset and progression of pathobiologically different heart muscle diseases may allow to the development of disease-specific curative therapy.

Precision prediction of heart failure events in patients with dilated cardiomyopathy and mildly reduced ejection fraction using multi-parametric cardiovascular magnetic resonance

AIMS

To assess whether left ventricular (LV) global longitudinal strain (GLS), derived from cardiovascular magnetic resonance (CMR), is associated with (i) progressive heart failure (HF), and (ii) sudden cardiac death (SCD) in patients with dilated cardiomyopathy with mildly reduced ejection fraction (DCMmrEF).

METHODS AND RESULTS

We conducted a prospective observational cohort study of patients with DCM and LV ejection fraction (LVEF) ≥40% assessed by CMR, including feature-tracking to assess LV GLS and late gadolinium enhancement (LGE). Long-term adjudicated follow-up included (i) HF hospitalization, LV assist device implantation or HF death, and (ii) SCD or aborted SCD (aSCD). Of 355 patients with DCMmrEF (median age 54 years [interquartile range 43-64], 216 men [60.8%], median LVEF 49% [46-54]) followed up for a median 7.8 years (5.2-9.4), 32 patients (9%) experienced HF events and 19 (5%) died suddenly or experienced aSCD. LV GLS was associated with HF events in a multivariable model when considered as either a continuous (per % hazard ratio [HR] 1.10, 95% confidence interval [CI] 1.00-1.21, p = 0.045) or dichotomized variable (LV GLS > -15.4%: HR 2.70, 95% CI 1.30-5.94, p = 0.008). LGE presence was not associated with HF events (HR 1.49, 95% CI 0.73-3.01, p = 0.270). Conversely, LV GLS was not associated with SCD/aSCD (per % HR 1.07, 95% CI 0.95-1.22, p = 0.257), whereas LGE presence was (HR 3.58, 95% CI 1.39-9.23, p = 0.008). LVEF was neither associated with HF events nor SCD/aSCD.

CONCLUSION

Multi-parametric CMR has utility for precision prognostic stratification of patients with DCMmrEF. LV GLS stratifies risk of progressive HF, while LGE stratifies SCD risk.

Predictors of failed left bundle branch pacing implant in heart failure with reduced ejection fraction: Importance of left ventricular diameter and QRS morphology

BACKGROUND

Left bundle branch pacing (LBBP) is considered an alternative to cardiac resynchronization therapy (CRT). However, LBBP is not suitable for all patients with heart failure.

OBJECTIVE

The aim of our study was to identify predictors of unsuccessful LBBP implantation in CRT candidates.

METHODS

A cohort of consecutive patients with indications for CRT were included. Clinical, echocardiographic, and electrocardiographic variables were prospectively recorded.

RESULTS

A total of 187 patients were included in the analysis. LBBP implantation was successful in 152 of 187 patients (81.2%) and failed in 35 of 187 patients (18.7%). The causes of unsuccessful implantation were unsatisfactory paced QRS morphology (28 of 35 [80%]), inability to screw the helix (4 of 35 [11.4%]), lead instability (2 of 35 [5.7%]), and high pacing thresholds (1 of 35 [2.8%]). The left ventricular end-diastolic diameter (LVEDD), non-LBBB (left bundle branch block) QRS morphology, and QRS width were predictors of failed implantation according to the univariate analysis. According to the multivariate regression analysis, LVEDD (odds ratio 1.31 per 5-mm increase; 95% confidence interval 1.05-1.63 per 5-mm increase; P = .02) and non-LBBB (odds ratio 3.07; 95% confidence interval 1.08-8.72; P = .03) were found to be independent predictors of unsuccessful LBBP implantation. An LVEDD of 60 mm has 60% sensitivity and 71% specificity for predicting LBBP implant failure.

CONCLUSION

When LBBP was used as CRT, LVEDD and non-LBBB QRS morphology predicted unsuccessful implantation. Non-LBBB triples the likelihood of failed implantation independent of LVEDD. Caution should be taken when considering these parameters to plan the best pacing strategy for patients.

Non-dilated left ventricular cardiomyopathy vs. dilated cardiomyopathy: clinical background and outcomes

AIMS

Non-dilated left ventricular cardiomyopathy (NDLVC) was proposed as a new category of cardiomyopathy that included patients with non-left ventricular (LV) dilatation, LV wall motion abnormality, or LV scar. However, the clinical background and event rates of NDLVC were unclear. The aim of this study was to examine the characteristics and event rates of patients with NDLVC and reduced LV ejection fraction (NDLVC-REF) in comparison with those with dilated cardiomyopathy (DCM).

METHODS AND RESULTS

We retrospectively included 363 patients with newly diagnosed non-ischaemic cardiomyopathy and reduced LV ejection fraction (<50%) between December 2004 and January 2018. Patients who did not have LV dilatation (LV dimension index of ≦31 mm/m2 in men and ≦34 mm/m2 in women) were categorized as NDLVC-REF (n = 80, 22.2%), and the remaining patients were categorized as DCM. Cardiac events were defined as sudden cardiac death and rehospitalization for heart failure. Patients with NDLVC-REF had a higher prevalence of atrial fibrillation and a higher LV ejection fraction than those with DCM at baseline. LV ejection fraction was higher and LV end-diastolic diameter was smaller in patients with NDLVC-REF than in those with DCM at all time points after diagnosis. During the median follow-up period of 68.8 months (interquartile range: 33.0-93.7 months), 44 patients experienced cardiac events. The Kaplan-Meier curves showed no significant differences in the probability of cardiac events among NDLVC-REF and DCM patients (P = 0.349). However, patients with NDLVC-REF and LV dilatation after diagnosis (14%) had a higher risk of cardiac events than those with NDLVC-REF without LV dilatation (P = 0.049).

CONCLUSIONS

There was no significant difference in the incidence of cardiac events between NDLVC-REF and DCM. Among NDLVC-REF patients, 18% of patients who showed LV dilatation after diagnosis had poor outcomes. Therefore, both NDLVC-REF and DCM patients may require equivalent attention to follow-up and regular assessment of LV function.

The Role of Magnetic Resonance Imaging in Cardiomyopathies in the Light of New Guidelines: A Focus on Tissue Mapping

Cardiomyopathies (CMPs) are a group of myocardial disorders that are characterized by structural and functional abnormalities of the heart muscle. These abnormalities occur in the absence of coronary artery disease (CAD), hypertension, valvular disease, and congenital heart disease. CMPs are an increasingly important topic in the field of cardiovascular diseases due to the complexity of their diagnosis and management. In 2023, the ESC guidelines on cardiomyopathies were first published, marking significant progress in the field. The growth of techniques such as cardiac magnetic resonance imaging (CMR) and genetics has been fueled by the development of multimodal imaging approaches. For the diagnosis of CMPs, a multimodal imaging approach, including CMR, is recommended. CMR has become the standard for non-invasive analysis of cardiac morphology and myocardial function. This document provides an overview of the role of CMR in CMPs, with a focus on tissue mapping. CMR enables the characterization of myocardial tissues and the assessment of cardiac functions. CMR sequences and techniques, such as late gadolinium enhancement (LGE) and parametric mapping, provide detailed information on tissue composition, fibrosis, edema, and myocardial perfusion. These techniques offer valuable insights for early diagnosis, prognostic evaluation, and therapeutic guidance of CMPs. The use of quantitative CMR markers enables personalized treatment plans, improving overall patient outcomes. This review aims to serve as a guide for the use of these new tools in clinical practice.

The Role of Artificial Intelligence in Echocardiography: A Clinical Update

PURPOSE OF REVIEW

In echocardiography, there has been robust development of artificial intelligence (AI) tools for image recognition, automated measurements, image segmentation, and patient prognostication that has created a monumental shift in the study of AI and machine learning models. However, integrating these measurements into complex disease recognition and therapeutic interventions remains challenging. While the tools have been developed, there is a lack of evidence regarding implementing heterogeneous systems for guiding clinical decision-making and therapeutic action.

RECENT FINDINGS

Newer AI modalities have shown concrete positive data in terms of user-guided image acquisition and processing, precise determination of both basic and advanced quantitative echocardiographic features, and the potential to construct predictive models, all with the possibility of seamless integration into clinical decision support systems. AI in echocardiography is a powerful and ever-growing tool with the potential for revolutionary effects on the practice of cardiology. In this review article, we explore the growth of AI and its applications in echocardiography, along with clinical implications and the associated regulatory, legal, and ethical considerations.

An in silico study of the effects of left ventricular assist device on right ventricular function and inter-ventricular interaction

BACKGROUND

Left ventricular assist device (LVAD) is associated with a high incidence of right ventricular (RV) failure, which is hypothesized to be caused by the occurring inter-ventricular interactions when the LV is unloaded. Factors contributing to these interactions are unknown.

METHODS

We used computer modeling to investigate the impact of the HeartMate 3 LVAD on RV functions. The model was first calibrated against pressure-volume (PV) loops associated with a heart failure (HF) patient and validated against measurements of inter-ventricular interactions in animal experiments. The model was then applied to investigate the effects of LVAD on (1) RV chamber contractility indexed byV 60 derived from its end-systolic PV relationship, and (2) RV diastolic function indexed byV 20 derived from its end-diastolic PV relationship. We also investigated how septal wall thickness and regional contractility affect the impact of LVAD on RV function.

RESULTS

The impact of LVAD on RV chamber contractility is small at a pump speed lower than 4k rpm. At a higher pump speed between 4k and 9k rpm, however, RV chamber contractility is reduced (by ~3% at 6k rpm and ~10% at 9k rpm). The reduction of RV chamber contractility is greater with a thinner septal wall or with a lower myocardial contractility at the LV free wall, septum, or RV free wall.

CONCLUSION

RV chamber contractility is reduced at a pump speed higher than 4k rpm, and this reduction is greater with a thinner septal wall or lower regional myocardial contractility. Findings here may have clinical implications in identifying LVAD patients who may suffer from RV failure.

Phenotype, outcomes and natural history of early-stage non-ischaemic cardiomyopathy

AIMS

To characterize the phenotype, clinical outcomes and rate of disease progression in patients with early-stage non-ischaemic cardiomyopathy (early-NICM).

METHODS AND RESULTS

We conducted a prospective observational cohort study of patients with early-NICM assessed by late gadolinium enhancement cardiovascular magnetic resonance (CMR). Cases were classified into the following subgroups: isolated left ventricular dilatation (early-NICM H-/D+), non-dilated left ventricular cardiomyopathy (early-NICM H+/D-), or early dilated cardiomyopathy (early-NICM H+/D+). Clinical follow-up for major adverse cardiovascular events (MACE) included non-fatal life-threatening arrhythmia, unplanned cardiovascular hospitalization or cardiovascular death. A subset of patients (n = 119) underwent a second CMR to assess changes in cardiac structure and function. Of 254 patients with early-NICM (median age 46 years [interquartile range 36-58], 94 [37%] women, median left ventricular ejection fraction [LVEF] 55% [52-59]), myocardial fibrosis was present in 65 (26%). There was no difference in the prevalence of fibrosis between subgroups (p = 0.90), however fibrosis mass was lowest in early-NICM H-/D+, higher in early-NICM H+/D- and highest in early-NICM H+/D+ (p = 0.03). Over a median follow-up of 7.9 (5.5-10.0) years, 28 patients (11%) experienced MACE. Non-sustained ventricular tachycardia (hazard ratio [HR] 5.1, 95% confidence interval [CI] 2.36-11.00, p < 0.001), myocardial fibrosis (HR 3.77, 95% CI 1.73-8.20, p < 0.001) and diabetes mellitus (HR 5.12, 95% CI 1.73-15.18, p = 0.003) were associated with MACE in a multivariable model. Only 8% of patients progressed from early-NICM to dilated cardiomyopathy with LVEF <50% over a median of 16 (11-34) months.

CONCLUSION

Early-NICM is not benign. Fibrosis develops early in the phenotypic course. In-depth characterization enhances risk stratification and might aid clinical management.

Comparison of Clinical Course and Outcomes between Dilated and Hypokinetic Non-Dilated Cardiomyopathy

BACKGROUND

By definition, dilated cardiomyopathy (DCM) is characterized by enlargement of the left ventricular (LV) cavity, and systolic dysfunction. However, in 2016 ESC introduced a new clinical entity - hypokinetic non-dilated cardiomyopathy (HNDC). HNDC is defined as LV systolic dysfunction without LV dilatation. However, the diagnosis of HNDC has so far rarely been made by a cardiologist, and it is unknown whether "classic" DCM differs from HNDC in terms of clinical course and outcomes.

OBJECTIVES

Comparison of heart failure profiles and outcomes between patients with "classic" dilated (DCM) and HNDCs.

METHOD

We retrospectively analysed 785 DCM patients, defined as impaired left ventricle (LV) systolic function (ejection fraction [LVEF] <45%) in the absence of coronary artery disease, valve disease, congenital heart disease, and severe arterial hypertension. "Classic" DCM was diagnosed when LV dilatation was present (LV end-diastolic diameter >52 mm/58 mm in women/men); otherwise, HNDC was diagnosed. After 47 ± 31 months, the all-cause mortality and composite endpoint (all-cause mortality, heart transplant - HTX, left ventricle assist device implantation - LVAD) were assessed.

RESULTS

There were 617 (79%) patients with LV dilatation. Patients with "classic" DCM differed from HNDC in terms of clinically relevant parameters [hypertension (47% vs. 64%, p = 0.008), ventricular tachyarrhythmias (29% vs. 15%, p = 0.007), NYHA class (2.5 ± 0.9 vs. 2.2 ± 0.8, p = 0.003)], had lower cholesterol (LDL: 2.9 ± 1.0 vs. 3.2 ± 1.1 mmol/L, p = 0.049), and higher N-terminal pro-brain natriuretic peptide (3,351 ± 5,415 vs. 2,563 ± 8584 pg/mL, p = 0.0001) and required higher diuretics dosages (57.8 ± 89.5 vs. 33.7 ± 48.7 mg/day, p ≤ 0.0001). All of their chambers were larger (LVEDd: 68.3 ± 4.5 vs. 52.7 ± 3.5 mm, p < 0.0001) and they had lower LVEF (25.2 ± 9.4 vs. 36.6 ± 11.7%, p < 0.0001). During the follow-up, there were 145 (18%) composite endpoints ("classic" DCM vs. HNDC: 122 [20%] vs. 26 [18%], p = 0.22): deaths (97 [16%] vs. 24 [14%], p = 0.67), HTX (17 [4%] vs. 4 [4%], p = 0.97) and LVAD (19 [5%] vs. 0 [0%], p = 0.03). Both groups did not differ in terms of all-cause mortality (p = 0.70), cardiovascular (CV) mortality (p = 0.37) and composite endpoint (p = 0.26).

CONCLUSIONS

LV dilatation was absent in more than one-fifth of DCM patients. HNDC patients had less severe heart failure symptoms, less advanced cardiac remodelling, and required lower diuretics dosages. On the other hand, "classic" DCM and HNDC patients did not differ in terms of all-cause mortality, CV mortality, and composite endpoint.

The Value of Multimodal Imaging in Early Phenotyping of Cardiomyopathies: A Family Case Report

Cardiomyopathies are structural and functional myocardial disorders that are not caused by other specific conditions such as coronary artery disease, arterial hypertension, valvular disease or congenital heart diseases. They are grouped into specific morphological and functional phenotypes, and sub-classified into familial and non-familial forms, with the dilated phenotype being the most frequent. However, there are many overlapping features between these phenotypes, complicating the diagnosis and management of patients. We report here the case of three related patients with different types of cardiomyopathies, emphasizing the importance of a multimodal approach to diagnosis.

A deep learning framework assisted echocardiography with diagnosis, lesion localization, phenogrouping heterogeneous disease, and anomaly detection

Echocardiography is the first-line diagnostic technique for heart diseases. Although artificial intelligence techniques have made great improvements in the analysis of echocardiography, the major limitations remain to be the built neural networks are normally adapted to a few diseases and specific equipment. Here, we present an end-to-end deep learning framework named AIEchoDx that differentiates four common cardiovascular diseases (Atrial Septal Defect, Dilated Cardiomyopathy, Hypertrophic Cardiomyopathy, prior Myocardial Infarction) from normal subjects with performance comparable to that of consensus of three senior cardiologists in AUCs (99.50% vs 99.26%, 98.75% vs 92.75%, 99.57% vs 97.21%, 98.52% vs 84.20%, and 98.70% vs 89.41%), respectively. Meanwhile, AIEchoDx accurately recognizes critical lesion regions of interest along with each disease by visualizing the decision-making process. Furthermore, our analysis indicates that heterogeneous diseases, like dilated cardiomyopathy, could be classified into two phenogroups with distinct clinical characteristics. Finally, AIEchoDx performs efficiently as an anomaly detection tool when applying handheld device-produced videos. Together, AIEchoDx provides a potential diagnostic assistant tool in either cart-based echocardiography equipment or handheld echocardiography device for primary and point-of-care medical personnel with high diagnostic performance, and the application of lesion region identification and heterogeneous disease phenogrouping, which may broaden the application of artificial intelligence in echocardiography.

Outcome and prognostic value of N-terminal pro-brain natriuretic peptide and high-sensitivity C-reactive protein in mildly dilated cardiomyopathy vs. dilated cardiomyopathy

AIMS

Mildly dilated cardiomyopathy (MDCM) was characterized as a subset of dilated cardiomyopathy (DCM) with systolic dysfunction and modest ventricular dilatation, of which the prognostic studies were limited. We aimed to compare the prognostic value of the N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hs-CRP) between MDCM and DCM.

METHODS AND RESULTS

We retrospectively included hospitalized patients diagnosed with DCM and a left ventricular ejection fraction ≤ 50% at Fuwai Hospital from 2006 to 2017. MDCM was defined as left ventricular end-diastolic diameter index (LVEDDi) ≤ 33 mm/m² in males and ≤34 mm/m² in females. A total of 640 patients (median age 49 years, 24.8% female) were included in this study. At baseline, 110 cases (17%) were categorized as MDCM and 529 cases (83%) as DCM. Of 282 patients who had follow-up echocardiograms ≥ 6 months, 7 MDCM patients (11.1%) evolved to DCM and 70 DCM patients (32.0%) recovered to MDCM by the change of LVEDDi. Compared with DCM, patients with baseline MDCM had lower composite risks of all-cause mortality, heart transplantation, and heart failure rehospitalization [adjusted hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.43-0.93, P = 0.019]. Both hs-CRP and NT-proBNP were independently associated with the composite endpoint in the overall cohort (hs-CRP: adjusted HR 1.07, 95% CI 1.00-1.15, P = 0.036; NT-proBNP: adjusted HR 1.11, 95% CI 1.02-1.22, P = 0.019). After a propensity-score matching between MDCM and DCM, higher NT-proBNP (above the median) was significantly associated with the outcome in DCM patients (HR 1.83, 95% CI 1.05-3.20, P = 0.034), but not in MDCM patients (HR 1.54, 95% CI 0.76-3.11, P = 0.227). On the contrary, higher hs-CRP (above the median) showed prognostic value for adverse events in MDCM patients (HR 3.19, 95% CI 1.52-6.66, P = 0.002), but not in DCM patients (HR 1.04, 95% CI 0.61-1.79, P = 0.88).

CONCLUSIONS

In patients with MDCM, although no evidence suggested the prognostic role of NT-proBNP, higher level of hs-CRP was associated with outcome, supporting the use of hs-CRP in risk stratification for patients with MDCM.

Prognostic Value of T1 Mapping and Feature Tracking by Cardiac Magnetic Resonance in Patients With Signs and Symptoms Suspecting Heart Failure and No Clinical Evidence of Coronary Artery Disease

Background

The ability of left ventricular ejection fraction (LVEF) and late gadolinium enhancement (LGE) by cardiac magnetic resonance for risk stratification in suspected heart failure is limited. We aimed to evaluate the incremental prognostic value of cardiac magnetic resonance‐assessed extracellular volume fraction (ECV) and global longitudinal strain (GLS) in patients with signs and symptoms suspecting heart failure and no clinical evidence of coronary artery disease.

Methods and Results

A total of 474 consecutive patients (57±21 years of age, 56% men) with heart failure‐related symptoms and absence of coronary artery disease underwent cardiac magnetic resonance. After median follow‐up of 18 months, 59 (12%) experienced the outcome of all‐cause death or heart failure hospitalization (DeathCHF). In univariate analysis, cardiac magnetic resonance‐assessed LVEF, LGE, GLS, and ECV were all significantly associated with DeathCHF. Adjusted for a multivariable baseline model including age, sex, LVEF and LGE, ECV, and GLS separately maintained a significant association with DeathCHF (ECV, hazard ratio [HR], 1.44 per 1 SD increase; 95% CI 1.13–1.84; P=0.003, and GLS, HR, 1.78 per 1 SD increase; 95% CI, 1.06–2.96; P=0.028 respectively). Adding both GLS and ECV to the baseline model significantly improved model discrimination (C statistic from 0.749 to 0.782, P=0.017) and risk reclassification (integrated discrimination improvement 0.046 [0.015–0.076], P=0.003; continuous net reclassification improvement 0.378 [0.065–0.752], P<0.001) for DeathCHF, beyond LVEF and LGE.

Conclusions

In patients with signs and symptoms suspecting heart failure and no clinical evidence of coronary artery disease, joint assessment of GLS and ECV provides incremental prognostic value for DeathCHF, independent of LVEF and LGE.

Extracorporeal Shock Wave Enhanced Exogenous Mitochondria into Adipose-Derived Mesenchymal Stem Cells and Further Preserved Heart Function in Rat Dilated Cardiomyopathy

This study tested whether extracorporeal shock wave (ECSW) supported-exogenous mitochondria (Mito) into adipose-derived mesenchymal stem cells (ADMSCs) would preserve left-ventricular-ejection-fraction (LVEF) in doxorubicin/12 mg/kg-induced dilated cardiomyopathy (DCM) rat. Adult-male-SD rats were equally categorized into group 1 (sham-control), group 2 (DCM), group 3 (DCM + ECSW/1.5 mJ/mm² for 140 shots/week × 3 times/since day 14 after DCM induction), group 4 (DCM + ECSW/1.5 mJ/mm²/100 shots-assisted mito delivery (500 μg) into ADMSCs/1.2 × 10⁶ cells, then implanted into LV myocardium day 14 after DCM induction) and group 5 (DCM + ECSW-assisted mito delivery into ADMSCs/1.2 × 10⁶ cells, then implanted into LV, followed by ECSW/1.5 mJ/mm² for 140 shots/week × 3 times/since day 14 after DCM induction) and euthanized by day 49. Microscopic findings showed mitochondria were abundantly enhanced by ECSW into H9C2 cells. The q-PCR showed a significant increase in relative number of mitDNA in mitochondrial-transferred H9C2 cells than in control group (p < 0.01). The angiogenesis/angiogenesis factors (VEGF/SDF-1α/IG-F1) in HUVECs were significantly progressively increased by a stepwise-increased amount of ECSW energy (0.1/0.25/0.35 mJ/mm²) (all p < 0.001). The 49-day LVEF was highest in group 1 and significantly progressively increased from groups 2 to 5 (all p < 0.0001). Cardiomyocyte size/fibrosis exhibited an opposite pattern of LVEF, whereas cellular/protein levels of angiogenesis factors (VEGF/SDF-1α) in myocardium were significantly progressively increased from groups 1 to 5 (all p < 0.0001). The protein expressions of apoptotic/mitochondrial (cleaved-caspase-3/cleaved-PARP/mitochondrial-Bax/cytosolic-cytochrome-C), fibrotic (p-Smad3/TGF-ß), oxidative-stress (NOX-1/NOX-2) and pressure-overload/heart failure (BNP/ß-MHC) biomarkers exhibited an opposite pattern of LVEF among the five groups (all p < 0.0001). ECSW-assisted mitochondrial-delivery into ADMSCs plus ECSW offered an additional benefit for preserving LVEF in DCM rat.

Contemporary etiology and prognosis of dilated non-ischemic cardiomyopathy

INTRODUCTION

Non-ischemic dilated cardiomyopathy (NI-DCM) represents a specific etiology of systolic heart failure that usually affect young individuals with a genetic background in up to 40% of cases. Behind the term NI-DCM there is a spectrum of different diseases, and an accurate etiological classification appears pivotal for the clinical management and prognostic stratification of these patients.

EVIDENCE ACQUISITION

In the last years the prognosis of NI-DCM patients dramatically improved thanks to the progresses in medical treatment/ device therapy and earlier diagnosis especially in familial context. In this review we summarize the actual state of art in the management of these patients.

EVIDENCE SYNTHESIS

In the era of precision medicine, a lot of progresses have been made to expand our knowledge on the management of NI-DCM patients. A complex interaction between genotype and external triggers is the main determinant of the clinical phenotype in NI-DCM, and a lot of efforts must be done by clinicians to systematically rule out all the possible causes involved in the pathogenesis. Progresses in cardiac imaging and familial screening led us to detect subtle abnormalities in the initial phase of the disease and also helped us to furtherly stratify the prognosis and arrhythmic risk of these patients. It is plausible that a more precise etiological classification will be needed in the near future.

CONCLUSIONS

NI-DCM contains a spectrum of different diseases. Proper etiological classification, early diagnosis and strict follow-up are essential to tailor care of these patients.

CMR-Based Risk Stratification of Sudden Cardiac Death and Use of Implantable Cardioverter-Defibrillator in Non-Ischemic Cardiomyopathy

Non-ischemic cardiomyopathy (NICM) is one of the most important entities for arrhythmias and sudden cardiac death (SCD). Previous studies suggest a lower benefit of implantable cardioverter–defibrillator (ICD) therapy in patients with NICM as compared to ischemic cardiomyopathy (ICM). Nevertheless, current guidelines do not differentiate between the two subgroups in recommending ICD implantation. Hence, risk stratification is required to determine the subgroup of patients with NICM who will likely benefit from ICD therapy. Various predictors have been proposed, among others genetic mutations, left-ventricular ejection fraction (LVEF), left-ventricular end-diastolic volume (LVEDD), and T-wave alternans (TWA). In addition to these parameters, cardiovascular magnetic resonance imaging (CMR) has the potential to further improve risk stratification. CMR allows the comprehensive analysis of cardiac function and myocardial tissue composition. A range of CMR parameters have been associated with SCD. Applicable examples include late gadolinium enhancement (LGE), T1 relaxation times, and myocardial strain. This review evaluates the epidemiological aspects of SCD in NICM, the role of CMR for risk stratification, and resulting indications for ICD implantation.

Protein Kinase C Alpha Cellular Distribution, Activity, and Proximity with Lamin A/C in Striated Muscle Laminopathies

Striated muscle laminopathies are cardiac and skeletal muscle conditions caused by mutations in the lamin A/C gene (LMNA). LMNA codes for the A-type lamins, which are nuclear intermediate filaments that maintain the nuclear structure and nuclear processes such as gene expression. Protein kinase C alpha (PKC-α) interacts with lamin A/C and with several lamin A/C partners involved in striated muscle laminopathies. To determine PKC-α’s involvement in muscular laminopathies, PKC-α’s localization, activation, and interactions with the A-type lamins were examined in various cell types expressing pathogenic lamin A/C mutations. The results showed aberrant nuclear PKC-α cellular distribution in mutant cells compared to WT. PKC-α activation (phos-PKC-α) was decreased or unchanged in the studied cells expressing LMNA mutations, and the activation of its downstream targets, ERK 1/2, paralleled PKC-α activation alteration. Furthermore, the phos-PKC-α-lamin A/C proximity was altered. Overall, the data showed that PKC-α localization, activation, and proximity with lamin A/C were affected by certain pathogenic LMNA mutations, suggesting PKC-α involvement in striated muscle laminopathies.

Prognostic value of multiple cardiac magnetic resonance imaging parameters in patients with idiopathic dilated cardiomyopathy

PURPOSE

Our study aimed to comprehensively explore efficient prognostic indicators in idiopathic dilated cardiomyopathy (IDCM) patients with reduced left ventricular ejection fraction (LVEF<40%).

BACKGROUND

Prognostic value of cardiac magnetic resonance(CMR) parameters for IDCM have been inconsistent.

METHODS

126 IDCM patients with reduced LVEF (<40%) were retrospectively enrolled. Cardiac function parameters, myocardial strain indices and myocardial fibrosis were evaluated. Laboratory data also were analyzed. The endpoint was a combination of major adverse cardiac events (MACEs), including cardiac death, heart transplantation, and rehospitalization. Prognostic value was evaluated by the Kaplan-Meier method and Cox regression.

RESULTS

During a median follow-up of 31 months, 44 patients experienced MACEs, including 9 deaths, 1 heart transplantation, and 34 rehospitalizations due to heart failure. Univariate and multivariate Cox analyses showed that cardiac function and myocardial strain indexes were not associated with the prognosis of IDCM (all p>0.05). NT-proBNP (HR 1.5, 95%CI: 1.053 to 2.137), Late‑gadolinium enhancement(LGE) mass (HR 1.022, 95%CI: 1.005 to 1.038), and LGE mass/left ventricle mass were significant predictors (HR 1.027, 95%CI: 1.007 to 1.046) for MACEs, all p < 0.05. Besides, poorest prognosis was observed in IDCM patients with positive LGE combined with NT-proBNP (log-rank = 27.261, p ≤ 0.001).

CONCLUSION

NT-proBNP and extent of LGE were reliable predictors in IDCM patients with reduced LVEF. Additionally, presence of LGE combined with NT-proBNP showed the strongest prognostic value in IDCM with reduced LVEF. Myocardial strain parameters seemed to have no prognostic value in IDCM patients with reduced LVEF.

Management of nonischemic-dilated cardiomyopathies in clinical practice: a position paper of the working group on myocardial and pericardial diseases of Italian Society of Cardiology

: Nonischemic-dilated cardiomyopathy (NIDCM) is an entity that gathers extremely heterogeneous diseases. This awareness, although leading to continuous improvement in survival, has increased the complexity of NIDCM patients' management. Even though the endorsed 'red-flags' approach helps clinicians in pursuing an accurate etiological definition in clinical practice, it is not clear when and how peripheral centers should interact with referral centers with specific expertise in challenging scenarios (e.g. postmyocarditis and genetically determined dilated cardiomyopathy) and with easier access to second-line diagnostic tools and therapies. This position paper will summarize each step in NIDCM management, highlighting the multiple interactions between peripheral and referral centers, from first-line diagnostic workup and therapy to advanced heart failure management and long-term follow-up.

Mapping the Minnesota Living with Heart Failure Questionnaire (MLHFQ) onto the Assessment of Quality of Life 8D (AQoL-8D) utility scores

PURPOSE

The Minnesota Living with Heart Failure Questionnaire (MLHFQ) is a widely used condition-specific measure of quality of life (QoL) in patients with heart failure. To use information from the MLHFQ in an economic evaluation, the MLHFQ must be mapped onto a preference-based measure of QoL. This study aims to develop a mapping algorithm between the MLHFQ and the Assessment of Quality of Life (AQoL) 8D utility instrument in patients with dilated cardiomyopathy (DCM).

METHODS

MLHFQ and AQoL-8D data were collected on 61 Australian adults with idiopathic DCM or other non-hypertrophic cardiomyopathies. Three statistical methods were used as follows: ordinary least squares (OLS) regression, the robust MM estimator, and the generalised linear models (GLM). Each included a range of explanatory variables. Model performance was assessed using key goodness-of-fit measures, the mean absolute error (MAE), and the root-mean-square error (RMSE).

RESULTS

The MLHFQ summary score and AQoL-8D utility scores were strongly correlated (r =  - 0.83, p < 0.0001) and the two subscales of the MLHFQ were correlated with the eight dimensions of the AQoL-8D. Utility scores were predicted with acceptable precision based on responses to the MLHFQ physical, emotional, social, and other subscales. OLS and GLM performed similarly with MAE and RMSE ranging 0.086-0.106 and 0.114-0.130, respectively.

CONCLUSION

The mapping algorithm developed in this study allows the derivation of AQoL-8D utilities from MLHFQ scores for use in cost-effectiveness analyses and most importantly, enables the economic evaluation of alternative heart failure therapy options when only the MLHFQ has been collected.

Speckle tracking echocardiography in hypokinetic non-dilated cardiomyopathy: comparison with dilated cardiomyopathy

Aims

Hypokinetic non‐dilated cardiomyopathy (HNDC), which is determined by impaired left ventricular (LV) systolic function despite normal LV size, has been categorized as a subgroup of dilated cardiomyopathy (DCM) spectrum. Lack of data regarding advanced echocardiographic data in this population motivated us to design the present study in order to assess LV myocardial deformation properties of HNDC patients against the ones with dilated left ventricle.

Methods and results

Thirty‐one HNDC patients and 23 DCM patients were enrolled in the study consecutively. Myocardial deformation parameters including global longitudinal strain, global circumferential strain, LV basal and apical rotation, LV twist, and LV mechanical dispersion were obtained with the use of two‐dimensional speckle tracking‐based methods in all patients. Left cardiac chamber volume was also measured using three‐dimensional HeartModel application. Patients with enlarged left ventricle tend to have lower LV ejection fraction. Comparing with HNDC group, DCM patients showed worse global circumferential strain (coefficient ± standard error 3.59 ± 0.94, P < 0.001) and LV mechanical dispersion (coefficient ± standard error 16.46 ± 7.09, P = 0.02) after regression analysis, while neither the global longitudinal strain nor the LV twist was not significantly different between two study population.

Conclusions

Left ventricular enlargement has a substantial effect on the circumferential strain and mechanical dispersion more than other deformation parameters that may play a role in the assumed poor prognosis of heart failure patients with dilated left ventricle.

How Left Ventricular Size Affects Severity of Disease and Long-term Prognosis in Patients with Severe Systolic Dysfunction?

BACKGROUND

We compared the severity of disease, heart failure (HF) rehospitalization and trend of changes over a 12-month follow-up in clinical and biochemical measurements between dilated cardiomyopathy (DCM) patients and those with left ventricular systolic dysfunction with normal LV size (NLVS). The existing definition of DCM failed to justify our observations in some clinical circumstances resulting in diagnostic and prognostic challenges.

METHODS

A total of 77 patients [52 (67.5%) male] including 40 patients in the NLVS group and 37 patients in the DCM group were enrolled and followed up for a median of 12 months [interquartile range, 11-14 months].

RESULTS

Mean left ventricular ejection fraction was statistically comparable between NLVS and DCM patients (22 ± 8% vs. 19 ± 6%, P = 0.08]. The New York Heart Association class was statistically comparable in both groups (P = 0.23). Laboratory measurements including hemoglobin, sodium, creatinine, uric acid, and NT-proBNP level were also statistically similar in both groups (all P > 0.05). During follow-up, HF rehospitalization occurred in 16 (76%) patients in NLVS and 5 (24%) patients in DCM groups (P = 0.009). Except for left ventricular ejection fraction which improved in both NLVS and DCM groups, no significant changes were observed in clinical (New York Heart Association class) and laboratory measurements during follow-up in both NLVS and DCM groups.

CONCLUSIONS

Our study showed that NLVS defines a group of systolic HF patients which not only did not have less severe disease than those with enlarged left ventricules (i.e., DCM), also had more HF rehospitalization. These NLVS patients also had steady clinical, laboratory, and echocardiographic profile during follow-up.

Dilated Cardiomyopathy With Mid-Range Ejection Fraction at Diagnosis: Characterization and Natural History

Background Limited data are available on mid-range ejection fraction (mrEF) patients with dilated cardiomyopathy. We sought to define the characteristics, evolution, and long-term prognosis of dilated cardiomyopathy patients with mrEF at diagnosis. Methods and Results We analyzed all dilated cardiomyopathy patients consecutively evaluated in the Trieste Heart Muscle Disease Registry from 1988 to 2013. mrEF and reduced ejection fraction (rEF) were defined as baseline left ventricular (LV) ejection fraction values between 40% and 49% and <40%, respectively. All-cause mortality or heart transplantation, sudden cardiac death, or major ventricular arrhythmias were considered as outcome measures. Worsening LV ejection fraction (reduction to <40%) during follow-up was also considered to identify possible predictors of adverse remodeling. Among 812 enrolled patients, 175 (22%) presented with mrEF at presentation. At baseline, as compared with the rEF group, mrEF patients had lower rates of moderate-severe mitral regurgitation and restrictive LV filling pattern. During a median follow-up period of 120 (60-204) months, the mrEF group presented a lower rate of death/heart transplantation (9% versus 36%, P<0.001) and sudden cardiac death or major ventricular arrhythmias (4.5% versus 15%, P<0.001) than rEF patients. Moreover, 29 out of 175 mrEF patients (17%) evolved to rEF. Restrictive LV filling pattern emerged as the strongest predictor of rEF development following multivariable analysis. Conclusions mrEF identified a consistent subgroup of dilated cardiomyopathy patients diagnosed in an earlier stage with subsequent apparent better long-term evolution. However, 17% of these patients evolved into rEF despite the use of medical therapy. A baseline restrictive LV filling pattern was independently associated with subsequent evolution to rEF.

A cost-effectiveness model of genetic testing and periodical clinical screening for the evaluation of families with dilated cardiomyopathy

Purpose

To assess the relative cost-effectiveness of cascade genetic testing in asymptomatic relatives of patients with dilated cardiomyopathy (DCM) compared with periodical clinical surveillance.

Methods

A decision-analytic model, combining a decision tree and a Markov model, was used to determine the lifetime costs and quality-adjusted life years (QALYs) for the two strategies. Deterministic and probabilistic sensitivity analyses were undertaken to assess the robustness of findings and to explore decision uncertainty.

Results

The incremental cost per additional QALY of cascade genetic testing prior to periodical clinical surveillance of first-degree relatives compared with periodical clinical surveillance alone was estimated at approximately AUD $6100. At established thresholds of cost-effectiveness, there is a 90% probability that cascade genetic testing is cost-effective. Extensive sensitivity analyses, including the addition of second-degree relatives, did not alter the conclusions drawn from the main analysis.

Conclusion

Using cascade genetic testing to guide clinical surveillance of asymptomatic relatives of patients with DCM is very likely to be cost-effective. As the DCM pathogenic variant detection rate rises and new evidence for personalized treatment of at-risk individuals becomes available, the cost-effectiveness of cascade testing will further increase.

"Primary" dilated hearts

Dilated cardiomyopathy is part of the spectrum of heart failure which is a syndrome with certain morphological and functional characteristics. Although significant progress in the management of those patients has been achieved, seems that risk stratification and future treatments will be related to the specific pathological substrate.

A shared-parameter continuous-time hidden Markov and survival model for longitudinal data with informative dropout

A shared-parameter approach for jointly modeling longitudinal and survival data is proposed. With respect to available approaches, it allows for time-varying random effects that affect both the longitudinal and the survival processes. The distribution of these random effects is modeled according to a continuous-time hidden Markov chain so that transitions may occur at any time point. For maximum likelihood estimation, we propose an algorithm based on a discretization of time until censoring in an arbitrary number of time windows. The observed information matrix is used to obtain standard errors. We illustrate the approach by simulation, even with respect to the effect of the number of time windows on the precision of the estimates, and by an application to data about patients suffering from mildly dilated cardiomyopathy.