Renin-angiotensin-aldosterone system genotype and serum BNP in a contemporary cohort of adults late after Fontan palliation

Int J Cardiol. 2015 Jun 18;197:209-215. doi: 10.1016/j.ijcard.2015.06.018. [Epub ahead of print]

Renin-angiotensin-aldosterone system genotype and serum BNP in a contemporary cohort of adults late after Fontan palliation.

Burchill LJ1Redington AN2Silversides CK1Ross HJ1Jimenez-Juan L1Mital S3Oechslin EN1Dragulescu A3Slorach C4Mertens L3Wald RM5.

Comment: This study evaluated associations between RAAS genotype, BNP levels and ventricular mass and function in a contemporary cohort of 106 adults after the Fontan operation. Patients were considered high-risk (n=31) if 2-5 homozygous RAAS risk genotypes were present or low risk if <1 pro-hypertrofic homozygous RAAS genotype was present. The prevalence of RAAS genotypes was comparable with the general population. Perhaps surprisingly, patients with high-risk genotype had similar blood pressure and ventricular mass on CMR when compared to low-risk patients. However, high-risk genotype was associated with higher BNP levels and diastolic dysfunction on echocardiogram. Fontan failure (heart failure admission, transplantation or death) occurred in 21patients during a mean of 9.5 years of follow-up. Multivariable analysis revealed that only higher baseline BNP remained predictive for Fontan failure (HR 1.11 [CI 1.01–1.23] for each 50 unit increase, p = 0.04). Importantly, predictors commonly associated with acquired heart disease, such as ventricular mass or ejection fraction were not predictive for Fontan failure. The findings of this study confirm the prognostic value of BNP in adult Fontan patients, RAAS genotype impact BNP levels and diastolic function in Fontan patients. The authors suggest accelerated ventricular fibrosis as opposed to hypertension and secondary ventricular hypertrophy may play a crucial role in disease progression of patients with high-risk RAAS genotype. Unfortunately, late gadolinium enhancement or T1-mapping CMR was available in an insufficient number of patients to test this hypothesis.