AUTHOR=Banydeen Rishika , Monfort Astrid , Inamo Jocelyn , Neviere Remi 

TITLE=Diagnostic and Prognostic Values of Cardiopulmonary Exercise Testing in Cardiac Amyloidosis

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2022.898033

DOI=10.3389/fcvm.2022.898033

ISSN=2297-055X

ABSTRACT=Cardiac amyloidosis (CA) is a myocardial disease characterized by extracellular amyloid infiltration throughout the heart, resulting in increased myocardial stiffness and restrictive heart wall chamber behavior. Its diagnosis among patients hospitalized for cardiovascular diseases is increasingly frequent, suggesting improved disease awareness and higher diagnostic capacities. 
One predominant functional manifestation of patients with CA is exercise intolerance, objectified by reduced peak oxygen uptake (VO2 peak), assessed by metabolic cart during cardiopulmonary exercise testing (CPET). Hemodynamic adaptation to exercise in CA patients is characterized by low myocardial contractile reserve and impaired myocardial efficiency. Rapid shallow breathing and hyperventilation, in absence of ventilatory limitation, are also typically observed in response to exercise. Ventilatory inefficiency is further suggested by elevated VE-VCO2 slope, which has been attributed to excessive sympathoexcitation and high physiological dead space (VD/VT) ratio during exercise. 
Growing evidence now suggests that, in addition to well-established biomarker risk models, a reduced VO2 peak is potentially a strong and independent predictive factor of adverse patient outcome, both for monoclonal immunoglobulin light chain (AL) or transthyretin (ATTR) cardiac amyloidosis. Beside generating prognostic information, CPET can be used for evaluation of the impact of therapeutic interventions in CA patients.