Genetic Etiology for Alcohol-Induced Cardiac Toxicity.

BACKGROUND Alcoholic cardiomyopathy (ACM) is defined by a dilated and impaired left ventricle due to chronic excess alcohol consumption. It is largely unknown which factors determine cardiac toxicity on exposure to alcohol. OBJECTIVES This study sought to evaluate the role of variation in cardiomyopathy-associated genes in the pathophysiology of ACM, and to examine the effects of alcohol intake and genotype on dilated cardiomyopathy (DCM) severity. METHODS The authors characterized 141 ACM cases, 716 DCM cases, and 445 healthy volunteers. The authors compared the prevalence of rare, protein-altering variants in 9 genes associated with inherited DCM. They evaluated the effect of genotype and alcohol consumption on phenotype in DCM. RESULTS Variants in well-characterized DCM-causing genes were more prevalent in patients with ACM than control subjects (13.5% vs. 2.9%; p ¼ 1.2 10 5), but similar between patients with ACM and DCM (19.4%; p ¼ 0.12) and with a predominant burden of titin truncating variants (TTNtv) (9.9%). Separately, we identified an interaction between TTN genotype and excess alcohol consumption in a cohort of DCM patients not meeting ACM criteria. On multivariate analysis, DCM patients with a TTNtv who consumed excess alcohol had an 8.7% absolute reduction in ejection fraction (95% confidence interval: 2.3% to 15.1%; p < 0.007) compared with those without TTNtv and excess alcohol consumption. The presence of TTNtv did not predict phenotype, outcome, or functional recovery on treatment in ACM patients. CONCLUSIONS TTNtv represent a prevalent genetic predisposition for ACM, and are also associated with a worse left ventricular ejection fraction in DCM patients who consume alcohol above recommended levels. Familial evaluation and genetic testing should be considered in patients presenting with ACM.post-print567 K

Outcome in Dilated Cardiomyopathy Related to the Extent, Location, and Pattern of Late Gadolinium Enhancement.

OBJECTIVES: This study sought to investigate the association between the extent, location, and pattern of late gadolinium enhancement (LGE) and outcome in a large dilated cardiomyopathy (DCM) cohort. BACKGROUND: The relationship between LGE and prognosis in DCM is incompletely understood. METHODS: The authors examined the association between LGE and all-cause mortality and a sudden cardiac death (SCD) composite based on the extent, location, and pattern of LGE in DCM. RESULTS: Of 874 patients (588 men, median age 52 years) followed for a median of 4.9 years, 300 (34.3%) had nonischemic LGE. Estimated adjusted hazard ratios for patients with an LGE extent of 0 to 2.55%, 2.55% to 5.10%, and >5.10%, respectively, were 1.59 (95% confidence interval [CI]: 0.99 to 2.55), 1.56 (95% CI: 0.96 to 2.54), and 2.31 (95% CI: 1.50 to 3.55) for all-cause mortality, and 2.79 (95% CI: 1.42 to 5.49), 3.86 (95% CI: 2.09 to 7.13), and 4.87 (95% CI: 2.78 to 8.53) for the SCD endpoint. There was a marked nonlinear relationship between LGE extent and outcome such that even small amounts of LGE predicted a substantial increase in risk. The presence of septal LGE was associated with increased mortality, but SCD was most associated with the combined presence of septal and free-wall LGE. Predictive models using LGE presence and location were superior to models based on LGE extent or pattern. CONCLUSIONS: In DCM, the presence of septal LGE is associated with a large increase in the risk of death and SCD events, even when the extent is small. SCD risk is greatest with concomitant septal and free-wall LGE. The incremental value of LGE extent beyond small amounts and LGE pattern is limited

Sex‐ and age‐based differences in the natural history and outcome of dilated cardiomyopathy

Aim: To evaluate the relationship between sex, age and outcome in dilated cardiomyopathy (DCM). Methods and results: We used proportional hazard modelling to examine the association between sex, age and all‐cause mortality in consecutive patients with DCM. Overall, 881 patients (290 women, median age 52 years) were followed for a median of 4.9 years. Women were more likely to present with heart failure (64.0% vs. 54.5%; P = 0.007) and had more severe symptoms (P 60 years of age was driven by non‐sudden death. Conclusion: Women with DCM have better survival compared to men, which may partly be due to less severe left ventricular dysfunction and a smaller scar burden. There is increased mortality driven by non‐sudden death in patients >60 years of age that is less marked in women. Outcomes with contemporary treatment were favourable, with a low incidence of sudden death

Phenotype and Clinical Outcomes of Titin Cardiomyopathy

BACKGROUND: Improved understanding of dilated cardiomyopathy (DCM) due to titin truncation (TTNtv) may help guide patient stratification. OBJECTIVES: The purpose of this study was to establish relationships among TTNtv genotype, cardiac phenotype, and outcomes in DCM. METHODS: In this prospective, observational cohort study, DCM patients underwent clinical evaluation, late gadolinium enhancement cardiovascular magnetic resonance, TTN sequencing, and adjudicated follow-up blinded to genotype for the primary composite endpoint of cardiovascular death, and major arrhythmic and major heart failure events. RESULTS: Of 716 subjects recruited (mean age 53.5 ± 14.3 years; 469 men [65.5%]; 577 [80.6%] New York Heart Association function class I/II), 83 (11.6%) had TTNtv. Patients with TTNtv were younger at enrollment (49.0 years vs. 54.1 years; p = 0.002) and had lower indexed left ventricular mass (5.1 g/m2 reduction; padjusted = 0.03) compared with patients without TTNtv. There was no difference in biventricular ejection fraction between TTNtv+/- groups. Overall, 78 of 604 patients (12.9%) met the primary endpoint (median follow-up 3.9 years; interquartile range: 2.0 to 5.8 years), including 9 of 71 patients with TTNtv (12.7%) and 69 of 533 (12.9%) without. There was no difference in the composite primary outcome of cardiovascular death, heart failure, or arrhythmic events, for patients with or without TTNtv (hazard ratio adjusted for primary endpoint: 0.92 [95% confidence interval: 0.45 to 1.87]; p = 0.82). CONCLUSIONS: In this large, prospective, genotype-phenotype study of ambulatory DCM patients, we show that prognostic factors for all-cause DCM also predict outcome in TTNtv DCM, and that TTNtv DCM does not appear to be associated with worse medium-term prognosis

Phenotype and Clinical Outcomes of Titin Cardiomyopathy.

BACKGROUND: Improved understanding of dilated cardiomyopathy (DCM) due to titin truncation (TTNtv) may help guide patient stratification. OBJECTIVES: The purpose of this study was to establish relationships among TTNtv genotype, cardiac phenotype, and outcomes in DCM. METHODS: In this prospective, observational cohort study, DCM patients underwent clinical evaluation, late gadolinium enhancement cardiovascular magnetic resonance, TTN sequencing, and adjudicated follow-up blinded to genotype for the primary composite endpoint of cardiovascular death, and major arrhythmic and major heart failure events. RESULTS: Of 716 subjects recruited (mean age 53.5 ± 14.3 years; 469 men [65.5%]; 577 [80.6%] New York Heart Association function class I/II), 83 (11.6%) had TTNtv. Patients with TTNtv were younger at enrollment (49.0 years vs. 54.1 years; p = 0.002) and had lower indexed left ventricular mass (5.1 g/m2 reduction; padjusted = 0.03) compared with patients without TTNtv. There was no difference in biventricular ejection fraction between TTNtv+/- groups. Overall, 78 of 604 patients (12.9%) met the primary endpoint (median follow-up 3.9 years; interquartile range: 2.0 to 5.8 years), including 9 of 71 patients with TTNtv (12.7%) and 69 of 533 (12.9%) without. There was no difference in the composite primary outcome of cardiovascular death, heart failure, or arrhythmic events, for patients with or without TTNtv (hazard ratio adjusted for primary endpoint: 0.92 [95% confidence interval: 0.45 to 1.87]; p = 0.82). CONCLUSIONS: In this large, prospective, genotype-phenotype study of ambulatory DCM patients, we show that prognostic factors for all-cause DCM also predict outcome in TTNtv DCM, and that TTNtv DCM does not appear to be associated with worse medium-term prognosis

Changes in clinical and imaging variables during withdrawal of heart failure therapy in recovered dilated cardiomyopathy.

AIMS: This study aimed to profile the changes in non-invasive clinical, biochemical, and imaging markers during withdrawal of therapy in patients with recovered dilated cardiomyopathy, providing insights into the pathophysiology of relapse. METHODS AND RESULTS: Clinical, biochemical, and imaging data from patients during phased withdrawal of therapy in the randomized or single-arm cross-over phases of TRED-HF were profiled. Clinical variables were measured at each study visit and imaging variables were measured at baseline, 16 weeks, and 6 months. Amongst the 49 patients [35% women, mean age 53.6 years (standard deviation 11.6)] who withdrew therapy, 20 relapsed. Increases in mean heart rate [7.6 beats per minute (95% confidence interval, CI, 4.5, 10.7)], systolic blood pressure [6.6 mmHg (95% CI 2.7, 10.5)], and diastolic blood pressure [5.8 mmHg (95% CI 3.1, 8.5)] were observed within 4-8 weeks of starting to withdraw therapy. A rise in mean left ventricular (LV) mass [5.1 g/m2 (95% CI 2.8, 7.3)] and LV end-diastolic volume [3.9 mL/m2 (95% CI 1.1, 6.7)] and a reduction in mean LV ejection fraction [-4.2 (95% CI -6.6, -1.8)] were seen by 16 weeks, the earliest imaging follow-up. Plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) fell immediately after withdrawing beta-blockers and only tended to increase 6 months after beginning therapy withdrawal [mean change in log NT-proBNP at 6 months: 0.2 (95% CI -0.1, 0.4)]. CONCLUSIONS: Changes in plasma NT-proBNP are a late feature of relapse, often months after a reduction in LV function. A rise in heart rate and blood pressure is observed soon after withdrawing therapy in recovered dilated cardiomyopathy, typically accompanied or closely followed by early changes in LV structure and function

Exposure to Elevated Nitrogen Dioxide Concentrations and Cardiac Remodeling in Patients With Dilated Cardiomyopathy.

BACKGROUND: Empirical evidence suggests a strong link between exposure to air pollution and heart failure incidence, hospitalizations, and mortality, but the biological basis of this remains unclear. We sought to determine the relationship between differential air pollution levels and changes in cardiac structure and function in patients with dilated cardiomyopathy. METHODS AND RESULTS: We undertook a prospective longitudinal observational cohort study of patients in England with dilated cardiomyopathy (enrollment 2009-2015, n = 716, 66% male, 85% Caucasian) and conducted cross sectional analysis at the time of study enrollment. Annual average air pollution exposure estimates for nitrogen dioxide (NO2) and particulate matter with diameter of 2.5 µm or less (PM2.5) at enrolment were assigned to each residential postcode (on average 12 households). The relationship between air pollution and cardiac morphology was assessed using linear regression modelling. Greater ambient exposure to NO2 was associated with higher indexed left ventricular (LV) mass (4.3 g/m2 increase per interquartile range increase in NO2, 95% confidence interval 1.9-7.0 g/m2) and lower LV ejection fraction (-1.5% decrease per interquartile range increase in NO2, 95% confidence interval -2.7% to -0.2%), independent of age, sex, socioeconomic status, and clinical covariates. The associations were robust to adjustment for smoking status and geographical clustering by postcode area. The effect of air pollution on LV mass was greatest in women. These effects were specific to NO2 exposure. CONCLUSIONS: Exposure to air pollution is associated with raised LV mass and lower LV ejection fraction, with the strongest effect in women. Although epidemiological associations between air pollution and heart failure have been established and supported by preclinical studies, our findings provide novel empirical evidence of cardiac remodeling and exposure to air pollution with important clinical and public health implications

Myocardial remodelling after withdrawing therapy for heart failure in patients with recovered dilated cardiomyopathy – insights from TRED-HF

Aims: To characterize adverse ventricular remodelling after withdrawing therapy in recovered dilated cardiomyopathy (DCM). Methods and results: TRED-HF was a randomized controlled trial with a follow-on single-arm cross-over phase that examined the safety and feasibility of therapy withdrawal in patients with recovered DCM over 6 months. The primary endpoint was relapse of heart failure defined by (i) a reduction in left ventricular (LV) ejection fraction >10% and to 10% increase in LV end-diastolic volume and to above the normal range, (iii) a twofold rise in N-terminal pro-B-type natriuretic peptide and to >400 ng/L, or (iv) evidence of heart failure. LV mass, LV and right ventricular (RV) global longitudinal strain (GLS) and extracellular volume were measured using cardiovascular magnetic resonance at baseline and follow-up (6 months or relapse) for 48 patients. LV cell and extracellular matrix masses were derived. The effect of withdrawing therapy, stratified by relapse and genotype, was investigated in the randomized and follow-on phases. In the randomized comparison, withdrawing therapy led to an increase in mean LV mass [5.4 g/m 2; 95% confidence interval (CI) 1.3–9.5] and cell mass (4.2 g/m 2; 95% CI 0.5–8.0) and a reduction in LV (3.5; 95% CI 1.6–5.5) and RV (2.4; 95% CI 0.1–4.7) GLS. In a non-randomized comparison of all patients (n = 47) who had therapy withdrawn in either phase, there was an increase in LV mass (6.2 g/m 2; 95% CI 3.6–8.9; P = 0.0001), cell mass (4.0 g/m 2; 95% CI 1.8–6.2; P = 0.0007) and matrix mass (1.7 g/m 2; 95% CI 0.7–2.6; P = 0.001) and a reduction in LV GLS (2.7; 95% CI 1.5–4.0; P = 0.0001). Amongst those who had therapy withdrawn and did not relapse, similar changes were observed (n = 28; LV mass: 5.1 g/m 2, 95% CI 1.5–8.8, P = 0.007; cell mass: 3.7 g/m 2, 95% CI 0.3–7.0, P = 0.03; matrix mass: 1.7 g/m 2, 95% CI 0.4–3.0, P = 0.02; LV GLS: 1.7, 95% CI 0.1–3.2, P = 0.04). Patients with TTN variants (n = 10) who had therapy withdrawn had a greater increase in LV matrix mass (mean effect of TTN: 2.6 g/m 2; 95% CI 0.4–4.8; P = 0.02). Conclusion: In TRED-HF, withdrawing therapy caused rapid remodelling, with early tissue and functional changes, even amongst patients who did not relapse