Tolerability and beneficial effects of sacubitril/valsartan on systemic right ventricular failure.

OBJECTIVE: Patients with a systemic right ventricle (sRV) in the context of transposition of the great arteries (TGA) after atrial switch or congenitally corrected TGA (ccTGA) are prone to sRV dysfunction. Pharmacological options for sRV failure remain poorly defined. This study aims to investigate the tolerability and effects of sacubitril/valsartan on sRV failure in adult patients with sRV. METHODS: In this two-centre, prospective cohort study, all consecutive adult patients with symptomatic heart failure and at least moderately reduced sRV systolic function were initiated on sacubitril/valsartan and underwent structured follow-up. RESULTS: Data of 40 patients were included (40% female, 30% ccTGA, median age 48 (44-53) years). Five patients discontinued therapy during titration. Median follow-up was 24 (12-36) months. The maximal dose was tolerated by 49% of patients. No episodes of hyperkalaemia or renal function decline occurred. Six-minute walking distance increased significantly after 6 months of treatment (569±16 to 597±16 m, p=0.016). Serum N-terminal-prohormone brain natriuretic peptide (NT-proBNP) levels decreased significantly after 3 months (567 (374-1134) to 404 (226-633) ng/L, p<0.001). Small, yet consistent echocardiographic improvements in sRV function were observed after 6 months (sRV global longitudinal strain: -11.1±0.5% to -12.6±0.7%, p<0.001, and fractional area change: 20% (16%-24%) to 26% (19%-30%), p<0.001). The linear mixed-effects model illustrated that after first follow-up moment, no time effect was present for the parameters. CONCLUSIONS: Treatment with sacubitril/valsartan was associated with a low rate of adverse effects in this adult sRV cohort. Persisting improvement in 6-minute walking test distance, NT-proBNP levels and echocardiographic parameters of sRV function was observed in an on-treatment analysis and showed no differential response based on sex or anatomy.

Causal effect estimation strategies in a longitudinal study with complex time-varying confounders: A tutorial.

The Dutch Sciatica Trial represents a longitudinal study with complex time-varying confounders as patients with poorer health conditions (e.g. more severe pain) are more likely to opt for surgery, which, in turn, may affect future outcomes (pain severity). A straightforward classical as-treated comparison at the end point would lead to biased estimation of the surgery effect. We present several strategies of causal treatment effect estimation that might be applicable for analyzing such data. These include an inverse probability of treatment weighted regression analysis, a marginal weighted analysis, an unweighted regression analysis, and several propensity score-based approaches. In addition, we demonstrate how to evaluate these approaches in a thorough simulation study where we generate various realistic complex confounding patterns akin to the sciatica study.

Risk stratification and treatment effect of statins in secondary cardiovascular prevention in old age: Additive value of N-terminal pro-B-type natriuretic peptide.

BACKGROUND: To date, no validated risk scores exist for prediction of recurrence risk or potential treatment effect for older people with a history of a cardiovascular event. Therefore, we assessed predictive values for recurrent cardiovascular disease of models with age and sex, traditional cardiovascular risk markers, and 'SMART risk score', all with and without addition of N-terminal pro-B-type natriuretic peptide (NT-proBNP). Treatment effect of pravastatin was assessed across low and high risk groups identified by the best performing models. DESIGN AND METHODS: Post-hoc analysis in 2348 participants (age 70-82 years) with a history of cardiovascular disease within the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) study. Composite endpoint was a recurrent cardiovascular event/cardiovascular mortality. RESULTS: The models with age and sex, traditional risk markers and SMART risk score had comparable predictive values (area under the curve (AUC) 0.58, 0.61 and 0.59, respectively). Addition of NT-proBNP to these models improved AUCs with 0.07 (p for difference ((pdiff)) = 0.003), 0.05 (pdiff = 0.009) and 0.06 (pdiff < 0.001), respectively. For the model with age, sex and NT-proBNP, the hazard ratio for the composite endpoint in pravastatin users compared with placebo was 0.67 (95% confidence interval 0.49-0.90) for those in the highest third of predicted risk and 0.91 (0.57-1.46) in the lowest third, number needed to treat 12 and 115 (pdiff = 0.038) respectively. CONCLUSION: In secondary cardiovascular prevention in old age addition of NT-proBNP improves prediction of recurrent cardiovascular disease, cardiovascular mortality and treatment effect of pravastatin. A minimal model including age, sex and NT-proBNP predicts as accurately as complex risk models including NT-proBNP.