P357 DOES CARDIAC AMYLOIDOSIS EVER HIDE A SEVERE AORTIC STENOSIS A CASE REPORT

Abstract Case presentation: A 89-year-old man, with an history of paroxysmal atrial fibrillation and chronic renal disease, was admitted to our ER for acute decompensated heart failure. He reported dyspnea on minimal exertion and worsening peripheral edema. He had a history of heart failure and a severe aortic stenosis first diagnosed in 2020 with an echocardiogram demonstrating a left ventricular ejection fraction (LVEF) of 30% and a low-flow low-gradient aortic stenosis (AVA=0,6 cmq, mean pressure gradient=21 mmHg). Besides, in 2019, he underwent a 99m Tc MDP scintigraphy for a prostatic nodule which showed important myocardial uptake of the bone tracer highly suggestive of cardiac amyloidosis. Urinary light chain assessment and determination of immunoglobulin light chain levels were negative for AL amyloidosis. The electrocardiogram showed: sinus rhythm, low voltage in the frontal leads and complete left bundle branch block with secondary repolarization abnormalities. The patient underwent transthoracic echocardiography for staging the severity of the aortic valve stenosis, which revealed borderline results: the aortic valve area was 0.5 cmq with a transaortic mean pressure gradient of 20 mmHg (EF 25%, with GLS of −5%). Low-dose dobutamine stress echocardiography was performed. At rest conditions, there was global hypokinesia with an ejection fraction of 24%. Aortic valve mean pressure was 19 mmHg referring to a calculated aortic valve opening area of 0,78 cmq. Under peak dobutamine stress (30 mcg/kg/min), LVEF increased to 36%. On the basis of these diagnostic findings, aortic stenosis was classified as pseudo-severe due to systolic dysfunction of the left ventricle with preserved contractile reserve. Besides, aortic calcium score of 574 confirmed that the aortic stenosis was non severe. Conclusions This case results exemplary of the fact that amyloidosis does not always hide a severe stenosis. Actually the echo with dobutamine indicates a non-valvular reason for heart-failure and no indication for valve replacement.The discharge suggestions consists of clinical/ echo follow ups and TTR stabilizers. Anyway, Tafamidis is not recommended because of the age and the patient short life expectancy. The implantation of CCM which, during the action potential platea delivers non-excitatory electrical currents and enhances systolic function in patients with heart failure, is proposed to obtain an improvement of symptoms.