Magnetic Resonance Imaging Characterization and Clinical Outcomes of Dilated and Arrhythmogenic Left Ventricular Cardiomyopathies.

BACKGROUND: Nondilated left ventricular cardiomyopathy (NDLVC) has been recently differentiated from dilated cardiomyopathy (DCM). A comprehensive characterization of these 2 entities using cardiac magnetic resonance (CMR) and genetic testing has never been performed. OBJECTIVES: This study sought to provide a thorough characterization and assess clinical outcomes in a large multicenter cohort of patients with DCM and NDLVC. METHODS: A total of 462 patients with DCM (227) or NDLVC (235) with CMR data from 4 different referral centers were retrospectively analyzed. The study endpoint was a composite of sudden cardiac death or major ventricular arrhythmias. RESULTS: In comparison to DCM, NDLVC had a higher prevalence of pathogenic or likely pathogenic variants of arrhythmogenic genes (40% vs 23%; P < 0.001), higher left ventricular (LV) systolic function (LV ejection fraction: 51% ± 12% vs 36% ± 15%; P < 0.001) and higher prevalence of free-wall late gadolinium enhancement (LGE) (27% vs 14%; P < 0.001). Conversely, DCM showed higher prevalence of pathogenic or likely pathogenic variants of nonarrhythmogenic genes (23% vs 12%; P = 0.002) and septal LGE (45% vs 32%; P = 0.004). Over a median follow-up of 81 months (Q1-Q3: 40-132 months), the study outcome occurred in 98 (21%) patients. LGE with septal location (HR: 1.929; 95% CI: 1.033-3.601; P = 0.039) was independently associated with the risk of sudden cardiac death or major ventricular arrhythmias together with LV dilatation, older age, advanced NYHA functional class, frequent ventricular ectopic activity, and nonsustained ventricular tachycardia. CONCLUSIONS: In a multicenter cohort of patients with DCM and NDLVC, septal LGE together with LV dilatation, age, advanced disease, and frequent and repetitive ventricular arrhythmias were powerful predictors of major arrhythmic events.

Tail length and E525K dilated cardiomyopathy mutant alter human ß-cardiac myosin super-relaxed state.

Dilated cardiomyopathy (DCM) is a condition characterized by impaired cardiac function, due to myocardial hypo-contractility, and is associated with point mutations in ß-cardiac myosin, the molecular motor that powers cardiac contraction. Myocardial function can be modulated through sequestration of myosin motors into an auto-inhibited "super-relaxed" state (SRX), which may be further stabilized by a structural state known as the "interacting heads motif" (IHM). Here, we sought to determine whether hypo-contractility of DCM myocardium results from reduced function of individual myosin molecules or from decreased myosin availability to interact with actin due to increased IHM/SRX stabilization. We used an established DCM myosin mutation, E525K, and characterized the biochemical and mechanical activity of wild-type and mutant human ß-cardiac myosin constructs that differed in the length of their coiled-coil tail, which dictates their ability to form the IHM/SRX state. We found that short-tailed myosin constructs exhibited low IHM/SRX content, elevated actin-activated ATPase activity, and fast velocities in unloaded motility assays. Conversely, longer-tailed constructs exhibited higher IHM/SRX content and reduced actomyosin ATPase and velocity. Our modeling suggests that reduced velocities may be attributed to IHM/SRX-dependent sequestration of myosin heads. Interestingly, longer-tailed E525K mutants showed no apparent impact on velocity or actomyosin ATPase at low ionic strength but stabilized IHM/SRX state at higher ionic strength. Therefore, the hypo-contractility observed in DCM may be attributable to reduced myosin head availability caused by enhanced IHM/SRX stability in E525K mutants.

Association of uncertain significance genetic variants with myocardial mechanics and morphometrics in patients with nonischemic dilated cardiomyopathy.

BACKGROUND: Careful interpretation of the relation between phenotype changes of the heart and gene variants detected in dilated cardiomyopathy (DCM) is important for patient care and monitoring. OBJECTIVE: We sought to assess the association between cardiac-related genes and whole-heart myocardial mechanics or morphometrics in nonischemic dilated cardiomyopathy (NIDCM). METHODS: It was a prospective study consisting of patients with NIDCM. All patients were referred for genetic testing and a genetic analysis was performed using Illumina NextSeq 550 and a commercial gene capture panel of 233 genes (Systems Genomics, Cardiac-GeneSGKit®). It was analyzed whether there are significant differences in clinical, two-dimensional (2D) echocardiographic, and magnetic resonance imaging (MRI) parameters between patients with the genes variants and those without. 2D echocardiography and MRI were used to analyze myocardial mechanics and morphometrics. RESULTS: The study group consisted of 95 patients with NIDCM and the average age was 49.7 ± 10.5. All echocardiographic and MRI parameters of myocardial mechanics (left ventricular ejection fraction 28.4 ± 8.7 and 30.7 ± 11.2, respectively) were reduced and all values of cardiac chambers were increased (left ventricular end-diastolic diameter 64.5 ± 5.9 mm and 69.5 ± 10.7 mm, respectively) in this group. It was noticed that most cases of whole-heart myocardial mechanics and morphometrics differences between patients with and without gene variants were in the genes GATAD1, LOX, RASA1, KRAS, and KRIT1. These genes have not been previously linked to DCM. It has emerged that KRAS and KRIT1 genes were associated with worse whole-heart mechanics and enlargement of all heart chambers. GATAD1, LOX, and RASA1 genes variants showed an association with better cardiac function and morphometrics parameters. It might be that these variants alone do not influence disease development enough to be selective in human evolution. CONCLUSIONS: Combined variants in previously unreported genes related to DCM might play a significant role in affecting clinical, morphometrics, or myocardial mechanics parameters.

Penetrance of Dilated Cardiomyopathy in Genotype-Positive Relatives.

BACKGROUND: Disease penetrance in genotype-positive (G+) relatives of families with dilated cardiomyopathy (DCM) and the characteristics associated with DCM onset in these individuals are unknown. OBJECTIVES: This study sought to determine the penetrance of new DCM diagnosis in G+ relatives and to identify factors associated with DCM development. METHODS: The authors evaluated 779 G+ patients (age 35.8 ± 17.3 years; 459 [59%] females; 367 [47%] with variants in TTN) without DCM followed at 25 Spanish centers. RESULTS: After a median follow-up of 37.1 months (Q1-Q3: 16.3-63.8 months), 85 individuals (10.9%) developed DCM (incidence rate of 2.9 per 100 person-years; 95% CI: 2.3-3.5 per 100 person-years). DCM penetrance and age at DCM onset was different according to underlying gene group (log-rank P = 0.015 and P <0.01, respectively). In a multivariable model excluding CMR parameters, independent predictors of DCM development were: older age (HR per 1-year increase: 1.02; 95% CI: 1.0-1.04), an abnormal electrocardiogram (HR: 2.13; 95% CI: 1.38-3.29); presence of variants in motor sarcomeric genes (HR: 1.92; 95% CI: 1.05-3.50); lower left ventricular ejection fraction (HR per 1% increase: 0.86; 95% CI: 0.82-0.90) and larger left ventricular end-diastolic diameter (HR per 1-mm increase: 1.10; 95% CI: 1.06-1.13). Multivariable analysis in individuals with cardiac magnetic resonance and late gadolinium enhancement assessment (n = 360, 45%) identified late gadolinium enhancement as an additional independent predictor of DCM development (HR: 2.52; 95% CI: 1.43-4.45). CONCLUSIONS: Following a first negative screening, approximately 11% of G+ relatives developed DCM during a median follow-up of 3 years. Older age, an abnormal electrocardiogram, lower left ventricular ejection fraction, increased left ventricular end-diastolic diameter, motor sarcomeric genetic variants, and late gadolinium enhancement are associated with a higher risk of developing DCM.

Clinical characteristics, treatment, trajectories and outcome of patients with dilated cardiomyopathy in a national heart failure registry.

BACKGROUND: Available data on the clinical characteristics and prognosis of patients with heart failure (HF) due to dilated cardiomyopathy (DCM) derive mainly from tertiary care centres for cardiomyopathies or from drug trial sub-studies, which may entail a referral bias. METHODS: From 2008 to 2021, we enrolled in a nationwide HF Registry 1886 DCM patients and 3899 with ischemic heart disease (IHD). RESULTS: Patients with DCM were younger, more often female, had more commonly recent onset HF, left bundle branch block, and showed higher LV end-diastolic volume and lower LVEF than IHD. With respect to IHD, DCM patients received more often mineralocorticoid receptor antagonists, renin angiotensin system inhibitors and betablockers, the latter more commonly at doses ≥50% of target, and triple guideline-directed medical therapy (GDMT) (adjusted OR 1.411, 95% CI 1.247-1.595, p < .0001). During one-year follow-up, 819 patients (14.2%) died or were hospitalized for HF [187 (9.9%) DCM, 632 (16.2%) IHD]; DCM was associated with lower risk of the combined end-point (adjusted HR 0.745, 95% CI 0.625- 0.888, p = .0011). Among the 1954 patients with 1-year echocardiograms available, 1483 had LVEF≤40% at baseline; of these,166 (30.6%) DCM and 165 (17.5%) IHD improved their LVEF to >40% (p < .0001). DCM aetiology was associated with higher likelihood of LVEF improvement (adjusted OR 1.722, 95% CI 1.328 -2.233, p < .0001). CONCLUSIONS: DCM patients have a different clinical profile, greater uptake of GDMT and better outcomes than IHD subjects. A comprehensive management approach is needed to further address the risk of unfavorable outcomes in DCM.

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.

Role of arrhythmic phenotype in prognostic stratification and management of dilated cardiomyopathy.

AIMS: Dilated cardiomyopathy (DCM) with arrhythmic phenotype combines phenotypical aspects of DCM and predisposition to ventricular arrhythmias, typical of arrhythmogenic cardiomyopathy. The definition of DCM with arrhythmic phenotype is not universally accepted, leading to uncertainty in the identification of high-risk patients. This study aimed to assess the prognostic impact of arrhythmic phenotype in risk stratification and the correlation of arrhythmic markers with high-risk arrhythmogenic gene variants in DCM patients. METHODS AND RESULTS: In this multicentre study, DCM patients with available genetic testing were analysed. The following arrhythmic markers, present at baseline or within 1 year of enrolment, were tested: unexplained syncope, rapid non-sustained ventricular tachycardia (NSVT), ≥1000 premature ventricular contractions/24 h or ≥50 ventricular couplets/24 h. LMNA, FLNC, RBM20, and desmosomal pathogenic or likely pathogenic gene variants were considered high-risk arrhythmogenic genes. The study endpoint was a composite of sudden cardiac death and major ventricular arrhythmias (SCD/MVA). We studied 742 DCM patients (45 ± 14 years, 34% female, 410 [55%] with left ventricular ejection fraction [LVEF] <35%). During a median follow-up of 6 years (interquartile range 1.6-12.1), unexplained syncope and NSVT were the only arrhythmic markers associated with SCD/MVA, and the combination of the two markers carried a significant additive risk of SCD/MVA, incremental to LVEF and New York Heart Association class. The probability of identifying an arrhythmogenic genotype rose from 8% to 30% if both early syncope and NSVT were present. CONCLUSION: In DCM patients, the combination of early detected NSVT and unexplained syncope increases the risk of life-threatening arrhythmic outcomes and can aid the identification of carriers of malignant arrhythmogenic genotypes.

Reduced Ejection Fraction in Elite Endurance Athletes: Clinical and Genetic Overlap With Dilated Cardiomyopathy.

BACKGROUND: Exercise-induced cardiac remodeling can be profound, resulting in clinical overlap with dilated cardiomyopathy, yet the significance of reduced ejection fraction (EF) in athletes is unclear. The aim is to assess the prevalence, clinical consequences, and genetic predisposition of reduced EF in athletes. METHODS: Young endurance athletes were recruited from elite training programs and underwent comprehensive cardiac phenotyping and genetic testing. Those with reduced EF using cardiac magnetic resonance imaging (defined as left ventricular EF <50%, or right ventricular EF <45%, or both) were compared with athletes with normal EF. A validated polygenic risk score for indexed left ventricular end-systolic volume (LVESVi-PRS), previously associated with dilated cardiomyopathy, was assessed. Clinical events were recorded over a mean of 4.4 years. RESULTS: Of the 281 elite endurance athletes (22±8 years, 79.7% male) undergoing comprehensive assessment, 44 of 281 (15.7%) had reduced left ventricular EF (N=12; 4.3%), right ventricular EF (N=14; 5.0%), or both (N=18; 6.4%). Reduced EF was associated with a higher burden of ventricular premature beats (13.6% versus 3.8% with >100 ventricular premature beats/24 h; P=0.008) and lower left ventricular global longitudinal strain (-17%±2% versus -19%±2%; P<0.001). Athletes with reduced EF had a higher mean LVESVi-PRS (0.57±0.13 versus 0.51±0.14; P=0.009) with athletes in the top decile of LVESVi-PRS having an 11-fold increase in the likelihood of reduced EF compared with those in the bottom decile (P=0.034). Male sex and higher LVESVi-PRS were the only significant predictors of reduced EF in a multivariate analysis that included age and fitness. During follow-up, no athletes developed symptomatic heart failure or arrhythmias. Two athletes died, 1 from trauma and 1 from sudden cardiac death, the latter having a reduced right ventricular EF and a LVESVi-PRS >95%. CONCLUSIONS: Reduced EF occurs in approximately 1 in 6 elite endurance athletes and is related to genetic predisposition in addition to exercise training. Genetic and imaging markers may help identify endurance athletes in whom scrutiny about long-term clinical outcomes may be appropriate. REGISTRATION: URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374976&isReview=true; Unique identifier: ACTRN12618000716268.

Pyroptosis Patterns Are Involved in Immune Microenvironment Regulation of Dilated Cardiomyopathy.

The importance of cell pyroptosis in immunity regulation is becoming increasingly obvious, especially in diseases of the cardiovascular system. Nevertheless, it is unknown whether the pyroptosis signalling pathway is involved in the immune microenvironment regulation of dilated cardiomyopathy (DCM). Therefore, the purpose of the study was to investigate the influence of pyroptosis on the immune environment in dilated cardiomyopathy. We found that expression of 19 pyrolysis-related genes (PRGs) in DCM samples was altered compared to healthy samples. Subsequently, based on these 12 hub pyrolysis-related genes, we developed a classifier that can distinguish between healthy samples and DCM samples. Among the hub pyrolysis-related genes, RT-PCR analyses demonstrated that five of them exhibited significant differential expression in DCM. Interestingly, we observed that immune characteristics are correlated with pyroptosis: higher expression of GSDMD is positively correlated with infiltrating activated pDCs; GSDMD is negatively correlated with Tregs; CASP1 is positively related to parainflammation; and CASP9 is negatively related to the type II IFN response. In addition, distinct pyroptosis-mediated patterns were identified, and immune characteristics under distinct patterns were revealed: pattern B mediates an active immune response, and pattern A leads to a relatively mild immune response to DCM. We also compared the biological functions between these patterns. Compared with pattern A, pattern B had more abundant pathways, such as the NOTCH signalling pathway and pentose phosphate pathway. In summary, this study proves the important influence of pyrolysis on the immune microenvironment of dilated cardiomyopathy and provides new clues for understanding the pathogenesis of dilated cardiomyopathy.

A 45-year-old man with sudden cardiac death, cutaneous abnormalities and a rare desmoplakin mutation: a case report and literature review.

BACKGROUND: Arrhythmogenic cardiomyopathy (AC) is a rare, heritable myocardial disorder that is a leading cause of ventricular arrhythmia and sudden cardiac death (SCD) in young people. Desmoplakin (DSP) mutations account for 3-20% of AC cases. However, the number of patients with DSP mutations is extremely small in all published reports and genotype-phenotype correlations are scant and mostly non-gene-specific. CASE PRESENTATION: A 45-year-old man was admitted after an out-of-hospital cardiac arrest, with documented ventricular fibrillation. He had no previous history of heart disease or family history of SCD or cardiomyopathy. The cardiac magnetic resonance showed a mildly dilated left ventricle with an ejection fraction of 30% and a non-dilated right ventricle with mildly depressed systolic function, and extensive subepicardial late gadolinium enhancement. Genetic screening identified a heterozygote nonsense mutation in DSP (NM_004415.2: c.478 C > T; p.Arg160Ter). Cascade genetic screening of the relatives revealed a high prevalence of the genotype and cutaneous phenotype, but a very low penetrance of the cardiac phenotype. CONCLUSIONS: We report a case of SCD and an autosomal dominant mutation in DSP that causes arrhythmogenic dilated cardiomyopathy/AC. Like the recessive mutation in DSP known to cause Carvajal syndrome, Arg160Ter may be associated with cutaneous abnormalities.

Nonsustained Ventricular Tachycardia Is Independently Associated With Sustained Ventricular Arrhythmias in Nonischemic Dilated Cardiomyopathy.

BACKGROUND: Spontaneous nonsustained ventricular tachycardia (NSVT) on Holter, VT inducibility during electrophysiology study, and late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) have been associated with sustained ventricular arrhythmias (SVAs) in nonischemic dilated cardiomyopathy (DCM). This study aimed to analyze whether these parameters carry independent prognostic value for spontaneous SVA in DCM. METHODS: Between 2011 and 2018, patients with the DCM clinical spectrum and documented SVA, suspected SVA, or considered to be at intermediate or high risk for SVA were enrolled in the prospective Leiden Nonischemic Cardiomyopathy Study. Patients underwent a comprehensive evaluation including 24-hour Holter, LGE-CMR, and electrophysiology study. Holters were assessed for the presence of NSVT (≥3 beats; rate, ≥120 bpm; lasting <30 s) and NSVT characteristics (coupling interval, duration, cycle length, morphology, regularity). Patients were followed at 6 to 12 monthly intervals. RESULTS: Of all 115 patients (age, 59±12 years; 77% men; left ventricular ejection fraction, 33±13%; history of SVA, 36%; LGE in 63%; median LGE mass, 13 g; interquartile range, 8-23 g), 62 (54%) had NSVT on Holter, and sustained monomorphic VT was inducible in 34 of 114 patients (30%). NSVT was not associated with LGE on CMR or VT inducibility during electrophysiology study nor were its features (all P>0.05). During 4.0±1.8 years of follow-up, SVA occurred in 39 patients (34%). NSVT (HR, 4.47 [95% CI, 1.87-10.72]; P=0.001) and VT inducibility (HR, 3.08 [95% CI, 1.08-8.81]; P=0.036) were independently associated with SVA during follow-up. A bivariable model including only noninvasively acquired parameters also allowed identification of a high-risk subgroup (ie, those with both NSVT and LGE on CMR). The findings remained similar when only patients without prior SVA were included. CONCLUSIONS: In patients with DCM, NSVT on Holter and VT inducibility during electrophysiology study predict SVA during follow-up independent of LGE on CMR. NSVTs may serve as an initiator, and sustained VT inducibility indicates the presence of the substrate for SVA in DCM. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01940081.

Nicotinamide riboside kinase-2 inhibits JNK pathway and limits dilated cardiomyopathy in mice with chronic pressure overload.

Nicotinamide riboside kinase-2 (NRK-2) has recently emerged as a critical regulator of cardiac remodeling however, underlying molecular mechanisms is largely unknown. To explore the same, NRK2 knockout (KO) and littermate control mice were subjected to trans-aortic constriction (TAC) or sham surgeries and cardiac function was assessed by serial M-mode echocardiography. A mild cardiac contractile dysfunction was observed in the KOs at the early adaptive phase of remodeling followed by a significant deterioration during the maladaptive cardiac remodeling phase. Consistently, NRK2 KO hearts displayed increased cardiac hypertrophy and heart failure (HF) reflected by morphometric parameters as well as increased fetal genes, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) expressions. Histological assessment revealed an extensive left ventricular (LV) chamber dilatation accompanied by elevated cardiomyopathy (CM) and fibrosis in the KO hearts post-TAC. In a gain-of-function model, NRK-2 overexpressing in AC16 cardiomyocytes displayed significantly attenuated fetal genes ANP and BNP expression. Consistently, NRK-2 overexpression attenuated angiotensin II (Ang II)-induced cardiomyocyte death. Mechanistically, we identified NRK-2 as a regulator of c-jun N-terminal kinase (JNK) MAP kinase and mitochondrial function where NRK-2 overexpression in human cardiomyocytes markedly suppressed the Ang II-induced JNK activation and mitochondrial depolarization. Thus, our results demonstrate that NRK-2 plays protective roles in pressure overload (PO)-induced dilatative cardiac remodeling and, genetic ablation exacerbates dilated cardiomyopathy (DCM), interstitial collagen deposition, and cardiac dysfunction post-TAC due, in part, to increased JNK activation and mitochondrial dysfunction.

Titin-truncating mutations associated with dilated cardiomyopathy alter length-dependent activation and its modulation via phosphorylation.

AIMS: Dilated cardiomyopathy (DCM) is associated with mutations in many genes encoding sarcomere proteins. Truncating mutations in the titin gene TTN are the most frequent. Proteomic and functional characterizations are required to elucidate the origin of the disease and the pathogenic mechanisms of TTN-truncating variants. METHODS AND RESULTS: We isolated myofibrils from DCM hearts carrying truncating TTN mutations and measured the Ca2+ sensitivity of force and its length dependence. Simultaneous measurement of force and adenosine triphosphate (ATP) consumption in skinned cardiomyocytes was also performed. Phosphorylation levels of troponin I (TnI) and myosin binding protein-C (MyBP-C) were manipulated using protein kinase A and λ phosphatase. mRNA sequencing was employed to overview gene expression profiles. We found that Ca2+ sensitivity of myofibrils carrying TTN mutations was significantly higher than in myofibrils from donor hearts. The length dependence of the Ca2+ sensitivity was absent in DCM myofibrils with TTN-truncating variants. No significant difference was found in the expression level of TTN mRNA between the DCM and donor groups. TTN exon usage and splicing were also similar. However, we identified down-regulation of genes encoding Z-disk proteins, while the atrial-specific regulatory myosin light chain gene, MYL7, was up-regulated in DCM patients with TTN-truncating variants. CONCLUSION: Titin-truncating mutations lead to decreased length-dependent activation and increased elasticity of myofibrils. Phosphorylation levels of TnI and MyBP-C seen in the left ventricles are essential for the length-dependent changes in Ca2+ sensitivity in healthy donors, but they are reduced in DCM patients with TTN-truncating variants. A decrease in expression of Z-disk proteins may explain the observed decrease in myofibril passive stiffness and length-dependent activation.

Outcomes after surgical ventricular restoration for ischemic cardiomyopathy.

OBJECTIVE: The study objective was to evaluate the short- and long-term outcomes of patients with ischemic cardiomyopathy after surgical ventricular restoration and to identify risk factors related to poor results. METHODS: Between August 2002 and April 2016, 62 patients affected by ischemic cardiomyopathy underwent surgical left ventricular restoration at our unit. Patients' mean age at operation was 63 years (39-79 years). Mean ejection fraction was 29.6%. The Surgical Treatment for Ischemic Heart Failure trial criteria have been used as indications for surgery. Fifty-seven patients (91%) received surgical myocardial revascularization. Mitral valve repair was performed in 39 patients (63%). The surgical technique consisted of the classic Dor operation or a different approach reducing the equatorial diameter of the left ventricle and avoiding the use of a patch. The data were analyzed retrospectively for perioperative results and short- and long-term clinical outcomes. RESULTS: One patient died of noncardiac causes within 30 days (1.6%). All-cause death occurred in 36 patients (58%) during follow-up (0.6-14.7 years; median follow-up time, 7.02 years), of whom 15 died of cardiac causes. Age, need for preoperative intra-aortic balloon pump, reduction less than 35% of postoperative left ventricular end-diastolic and end-systolic volumes, type of surgical technique, and ejection fraction less than 25% were identified as risk factors for late cardiac mortality. Perioperative levosimendan administration and presence of preoperative moderate to severe mitral regurgitation influenced early and intermediate-term outcomes, but no statistical relevance on long-term results was demonstrated. CONCLUSIONS: Patients with ischemic dilative cardiomyopathy have favorable short- and long-term outcomes after ventricular restoration. Age, preoperative ejection fraction less than 25%, inadequate left ventricular surgical reverse remodeling, and type of surgical technique negatively affect long-term survival.

Left Atrial Function Predicts Outcome in Dilated Cardiomyopathy: Fast Long-Axis Strain Analysis Derived from MRI.

Background There is increasing recognition that left atrial (LA) function is prognostically important in cardiovascular disease. LA strain is a sensitive parameter to describe complex LA phasic function. However, the prognostic value of LA strain in participants with idiopathic dilated cardiomyopathy (DCM) remains unclear. Purpose To evaluate the prognostic value of LA strain derived from cardiac MRI in study participants with idiopathic DCM. Materials and Methods Participants with idiopathic DCM who underwent cardiac MRI between June 2012 and November 2018 were prospectively enrolled. The fast long-axis strain MRI method was performed to assess LA strain. The primary end point was all-cause mortality and heart transplant, and the secondary end point was a combination of primary end point, heart failure readmission, and aborted sudden cardiac death. Cox regression analyses and Kaplan-Meier survival analysis were performed to identify the association between variables and outcomes. Results There were 497 participants (mean age, 47 years ± 14 [standard deviation]; 357 men) evaluated. During a median follow-up of 36 months (interquartile range, 26-54 months), 113 participants reached primary end points and 203 participants reached secondary end points. LA reservoir, conduit and booster strain, and strain rate were lower in participants with primary end points (P < .001). In multivariable Cox regression analysis, LA reservoir strain and conduit strain were independent predictors for primary end point (hazard ratio [HR] per 1% increase, 0.95 [95% CI: 0.91, 0.99; P = .008] and 0.92 [95% CI: 0.87, 0.98; P = .010], respectively) and secondary end points (HR per 1% increase, 0.95 [95% CI: 0.93, 0.97; P < .001] and 0.93 [95% CI: 0.89, 0.97; P < .001], respectively). In addition, LA reservoir strain and conduit strain added incremental prognostic value to clinical risk factors and late gadolinium enhancement presence (all, P < .05). Conclusion Left atrial reservoir and conduit strain, derived from cardiac MRI by using the fast long-axis method, were independent predictors of adverse clinical outcomes in idiopathic dilated cardiomyopathy. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Ambale-Venkatesh in this issue.

Analysis of SIRT4 gene single-nucleotide polymorphisms in a Han Chinese population with dilated cardiomyopathy.

Aim: We aimed to investigate the association of SIRT4 gene polymorphisms with the susceptibility and prognosis of dilated cardiomyopathy (DCM) in a Chinese population. Materials & methods: A total of 369 controls and 373 DCM patients were enrolled. Three tag single-nucleotide polymorphisms (rs2261612, rs2522138 and rs16950058) on SIRT4 were evaluated. Results: G carriers of rs2261612 were associated with the susceptibility of DCM in codominant, dominant and overdominant genetic models (all p < 0.01). Furthermore, the AG/GG and AG genotype of rs2261612 in dominant and overdominant models correlated with poor prognosis of DCM, independent of left ventricular ejection fraction and cardiac resynchronization therapy (p < 0.001). Conclusion:SIRT4 polymorphisms were associated with the susceptibility and prognosis of DCM in a Chinese population.