Mortality in pulmonary arterial hypertension due to congenital heart disease: Serial changes improve prognostication.

BACKGROUND: Adult patients with pulmonary arterial hypertension due to congenital heart disease (PAH-CHD) suffer from high mortality. This underlines the importance of adequate risk stratification to guide treatment decisions. Several baseline parameters are associated with mortality, however, their prognostic value may weaken after years of follow-up. Therefore we investigated the prognostic value of serial changes in standard clinical parameters in PAH-CHD. METHODS: In this prospective observational cohort study we included consecutive PAH-CHD adults, between 2005 and 2016. Control visits to the outpatient clinic were standardized, including functional, biochemical and echocardiographic tests, according to the guidelines. The prognostic value of serial changes was determined with time-dependent Cox regression. RESULTS: Ninety-two patients with PAH-CHD were included (age 43±15years, 34% male, 38% Down, 73% Eisenmenger). During a median follow-up of 6.0 (IQR 3.7-9.3) years, 35 (38%) patients died. Serial changes in World Health Organization functional classification (WHO-FC, HR 18.34 for onset class IV), six-minute walk distance (6-MWD, HR 0.65 per 50m), oxygen saturation at peak exercise (peak SaO2, HR 0.74 per 5%), NTproBNP (HR 2.25 per 1000ng/l) and echocardiographic right ventricular function (TAPSE, HR 0.80 per 0.5cm) significantly predicted mortality. Moreover, serial changes in these parameters were more potent predictors compared to baseline parameters, based on reduction in -2 log likelihood. CONCLUSIONS: Serial changes in standard clinical parameters have more prognostic value compared to baseline parameters in PAH-CHD. Our results emphasize the importance of screening for serial changes since periodical assessment could guide treatment decisions to delay disease progression.

Treatment of pulmonary arterial hypertension in congenital heart disease in Singapore versus the Netherlands: age exceeds ethnicity in influencing clinical outcome.

BACKGROUND: Advanced treatment of pulmonary arterial hypertension (PAH) in congenital heart disease (CHD) is increasingly applied worldwide following the-mainly Western world based-international PAH-CHD guidelines. However, studies comparing clinical presentation and outcome after the initiation of PAH-specific treatment are lacking. We aimed to analyse this in a Singaporean and Dutch cohort of PAH-CHD patients. METHODS: Adult CHD patients starting PAH-specific therapy, enrolled in two nationwide registries, were analysed. Patients received phosphodiesterase-type-5 inhibitors, endothelin receptor antagonists, or a combination. Change in six-minute walk test (6MWT) during follow-up was analysed using linear mixed model analysis. Determinants for mortality were assessed using Cox proportional hazard analyses. RESULTS: A total of 74 patients, 45 Dutch (mean age 47 ± 14 years) and 29 Singaporean (mean age 41 ± 14 years) were analysed. Despite a lower 6MWT (312 versus 395 metres, p = 0.01) and peak VO2 (35 versus 49 % of predicted, p = 0.01) at baseline in Singaporean patients, the treatment effect was similar in the two populations. Age at initiation of therapy (per 5 year lower age, ß = + 4.5, p = 0.017) was the strongest predictor of improvement in exercise capacity, corrected for ethnicity, baseline 6MWT, sex and CHD defect. CONCLUSIONS: Patients from Singapore had a worse clinical performance at baseline compared with the PAH-CHD patients from the Netherlands. No relation between ethnicity and improvement in 6MWT after PAH-specific therapy was found. Age at initiation of PAH-specific therapy was the strongest predictor of treatment efficacy and mortality, emphasising the need for early initiation of treatment in these patients.

Decrease in quality of life predicts mortality in adult patients with pulmonary arterial hypertension due to congenital heart disease.

BACKGROUND: Decrease in quality of life (QoL) in left-sided heart failure precedes poor survival, which can be reversed with exercise training. We investigated whether QoL is associated with mortality in pulmonary arterial hypertension due to congenital heart disease (PAH-CHD) patients. METHODS: In this observational study, PAH-CHD adults referred for PAH-specific therapy were included. QoL surveys (SF36) were recorded during 2 years of therapy. Based on shift in SF36 scores during this period, patients had either decreased or non-decreased QoL. Subsequently, the patients were followed for mortality. RESULTS: Thirty-nine PAH-CHD patients (mean age 42, 44 % male, 49 % Down's syndrome) were analysed. Following PAH-specific therapy, SF36 physical component summary (PCS) decreased in 13 (35-31 points, p = 0.001) and showed no decrease in 26 patients (34-43 points, mean values, p < 0.001). Post-initiation phase, median follow-up was 4.5 years, during which 12 deaths occurred (31 %), 10 (56 %) in the decreased and 2 (10 %) in the non-decreased group (p = 0.002). Cox regression showed a decrease in SF36 PCS predicted mortality (HR 3.4, 95 % CI 1.03-11, p = 0.045). CONCLUSIONS: In PAH-CHD patients, decrease in SF36 PCS following initiation of PAH-specific therapy is a determinant of mortality.