Aplicaciones de la genética a la cardiología clínica: hipercolesterolemia familiar y miocardiopatía dilatada alcohólica

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Medicina, Departamento de Medicina. Fecha de lectura: 17-12-201

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

Genetically Confirmed Familial Hypercholesterolemia in Patients With Acute Coronary Syndrome

BACKGROUND: Genetic screening programs in unselected individuals with increased levels of low-density lipoprotein cholesterol (LDL-C) have shown modest results in identifying individuals with familial hypercholesterolemia (FH). OBJECTIVES: This study assessed the prevalence of genetically confirmed FH in patients with acute coronary syndrome (ACS) and compared the diagnostic performance of FH clinical criteria versus FH genetic testing. METHODS: Genetic study of 7 genes (LDLR, APOB, PCSK9, APOE, STAP1, LDLRAP1, and LIPA) associated with FH and 12 common alleles associated with polygenic hypercholesterolemia was performed in 103 patients with ACS, age ≤65 years, and LDL-C levels ≥160 mg/dl. Dutch Lipid Clinic (DLC) and Simon Broome (SB) FH clinical criteria were also applied. RESULTS: The prevalence of genetically confirmed FH was 8.7% (95% confidence interval [CI]: 4.3% to 16.4%; n = 9); 29% (95% CI: 18.5% to 42.1%; n = 18) of patients without FH variants had a score highly suggestive of polygenic hypercholesterolemia. The prevalence of probable to definite FH according to DLC criteria was 27.2% (95% CI: 19.1% to 37.0%; n = 28), whereas SB criteria identified 27.2% of patients (95% CI: 19.1% to 37.0%; n = 28) with possible to definite FH. DLC and SB algorithms failed to diagnose 4 (44%) and 3 (33%) patients with genetically confirmed FH, respectively. Cascade genetic testing in first-degree relatives identified 6 additional individuals with FH. CONCLUSIONS: The prevalence of genetically confirmed FH in patients with ACS age ≤65 years and with LDL-C levels ≥160 mg/dl is high (approximately 9%). FH clinical algorithms do not accurately classify patients with FH. Genetic testing should be advocated in young patients with ACS and high LDL-C levels to allow prompt identification of patients with FH and relatives at risk.This research was supported in part by the Instituto de Salud Carlos III (grants RD012/0042/0066 and CB16/11/00432), Spanish Ministry of Economy and Competitiveness (grant SAF2015-71863-REDT), and Alexion through an Investigator Initiated Research Grant. Grants from the Instituto de Salud Carlos III and the Spanish Ministry of Economy and Competitiveness are supported by the Plan Estatal de I+D+I 2013-2016 European Regional Development Fund (FEDER), "A way of making Europe." The sponsors played no role in the design, collection, analysis, or interpretation of the data or in the decision to submit the manuscript for publication. Drs. Castillo, Lluis-Ganella, and Quintana are employees of Gendiag.exe/Ferrer inCode.S

Impacto pronóstico y factores predictores de la recuperación de la fracción de eyección en pacientes con miocardiopatía dilatada alcohólica.

Introducción y objetivos: La recuperación de la fracción de eyección del ventrículo izquierdo (FEVI) está descrita en la miocardiopatía alcohólica (MCA) tras la abstinencia alcohólica. Sin embargo, se desconoce el impacto pronóstico de esta recuperación y los factores a los que se asocia. Nuestro objetivo es definir el papel pronóstico a largo plazo de la mejoría de la FEVI en la MCA e identificar sus predictores. Métodos: Se evaluaron 101 pacientes con MCA con una mediana de seguimiento de 82 meses [rango intercuartílico 36–134]. Resultados: Al final del seguimiento, 42 pacientes (42%) mostraron una recuperación significativa de la FEVI, definida como un incremento absoluto ≥ 10% y FEVI final ≥ 40%. Estos pacientes mostraron mejor pronóstico que aquellos sin recuperación de la FEVI (trasplante cardiaco o muerte cardiovascular 1 frente al 30%; p < 0,001). La duración del QRS < 120 ms (OR = 6,68; IC95%, 2,30-19,41), el tratamiento bloqueador beta (OR = 3,01; IC95%, 1,09-8,28), y no necesitar diuréticos (OR = 3,35; IC95%, 1,08-10,42) predijeron la recuperación de la FEVI en el análisis multivariado. Aunque el cese del consumo de alcohol no fue predictor, ninguno de los pacientes (n = 6) que mantuvo un consumo excesivo recuperaron la FEVI. El número de pacientes que recuperaron la FEVI entre los abstemios y aquellos que mantuvieron un consumo moderado fue similar (44 frente al 45%; p = 0,9). Conclusiones: La recuperación de la FEVI se asocia con un excelente pronóstico en la MCA. El tratamiento betabloqueante, un QRS < 120 ms y no tomar diuréticos son predictores independientes de esta recuperación. La recuperación de la FEVI es similar entre bebedores moderados y abstemios.pre-print388 K

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Genetic Etiology for Alcohol-Induced Cardiac Toxicity

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. 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. 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. Variants in well-characterized DCM-causing genes were more prevalent in patients with ACM than control subjects (13.5% vs. 2.9%; p = 1.2 ×10 ⁻⁵), but similar between patients with ACM and DCM (19.4%; p = 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. 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