Abstract P304: Coronary Flow Reserve In Primary Aldosteronism

Abstract

Introduction: Primary aldosteronism (PA) is characterized by excess cardiovascular risk, underpinned by evidence of microvascular dysfunction. Whether this extends to the coronary vasculature and, as such, regresses after appropriate treatment remains to be determined. Aim: To investigate the presence of coronary microvascular dysfunction and its reversibility in PA patients. Methods: Fifteen PA patients with evidence of lateralized aldosterone overproduction at adrenal vein sampling underwent Doppler echocardiography for the assessment of Coronary flow reserve (CFR: diastolic peak flow on the anterior descending coronary artery during pharmacological [dipyridamole, n=14] or physical stress [n=1] -induced hyperaemia/basal flow) and the ratio between diastolic peak flow and left ventricle mass (FMR), at the time of diagnosis (after withdrawal of RAAS-interfering drugs and normalization of kalemia with K supplementation) and 4-6 months after specific treatment. In case CFR was ≤ 2.5 or the stress protocol suggested potential ischemia, regardless of CFR, a coronary CT angiography (coroCT) was performed to exclude underlying macrovascular coronary artery disease. Results: Out of 15 PA patients (5F; 52±10 yo; BP:149/91±17/11 mmHg; sK + =3.5±0.6 at diagnosis and 3.8±0.3 mmol/L on KCl supplements; DRC=3.0 [2.0-5.5] mIU/L; PAC=747 [417-1430] pmol/L), 14 were cured by unilateral adrenalectomy (127/81±13/11 mmHg; sK + =4.3±0.4 mmol/L; DRC=11.8 [6.7-19.2] mIU/L; PAC=200 [136-244] pmol/L, p<0.05 for all); one patient experienced incomplete biochemical cure and was managed with long-term mineralocorticoid receptor antagonism. At the time of diagnosis, n=7 (46%), n=3 (20%) and n=1 (7%) patients showed CFR ≤ 3.0, 2.5 and 2.0, respectively; none had evidence of macrovascular disease at coroCT. In parallel to a reduction in left ventricular mass (trend; p=0.084), both CFR and FRM significantly increased after treatment (CFR=3.1 [2.6-3.3] vs. 3.4 [3.1-4.6], p=0.013; FMR=0.71±0.33 vs. 0.91±0.32 cm x g/sec x m 2 , p=0.038). Conclusions: Treatment of PA improves coronary microvascular function, as assessed by established prognostic indices like CFR and FMR.