252. Cardio-Oncology: Cardiac Amyloidosis with Dr. Omar Siddiqi

The importance of recognition and diagnosis of cardiac amyloidosis is at an all-time high due to its high prevalence and improved therapeutic strategies. Here we discuss what CardioNerds need to know about the manifestations, diagnosis, and management of transthyretin (ATTR) and light chain (AL) cardiac amyloidosis. Join Dr. Dan Ambinder (CardioNerds Cofounder), Dr. Dinu-Valentin Balanescu (Series Cochair, Chief Resident at Beaumont Health, and soon FIT at Mayo Clinic), and Dr. Dan Davies (Episode FIT Lead and FIT at Mayo Clinic) as they discuss cardiac amyloidosis with Dr. Omar Siddiqi, cardiologist at the Boston University Amyloidosis Center and program director for the general cardiovascular fellowship program at Boston University, a CardioNerds Healy Honor Roll Program. Episode notes were drafted by Dr. Dan Davies. Audio editing by CardioNerds Academy Intern, student doctor Chelsea Amo Tweneboah. Access the CardioNerds Cardiac Amyloidosis Series for a deep dive into this important topic. This episode is supported by a grant from Pfizer Inc. This CardioNerds Cardio-Oncology series is a multi-institutional collaboration made possible by contributions of stellar fellow leads and expert faculty from several programs, led by series co-chairs, Dr. Giselle Suero Abreu, Dr. Dinu Balanescu, and Dr. Teodora Donisan.  Pearls • Notes • References • Production Team CardioNerds Cardio-Oncology PageCardioNerds Episode PageCardioNerds AcademyCardionerds Healy Honor Roll CardioNerds Journal ClubSubscribe to The Heartbeat Newsletter!Check out CardioNerds SWAG!Become a CardioNerds Patron! Pearls and Quotes Cardiac amyloidosis is no longer considered a rare disease, especially transthyretin amyloidosis in older male patients with HFpEF and aortic stenosis. Echocardiogram is the “gate keeper” of cardiac imaging and provides initial evidence of amyloid infiltration, while cardiac MRI can help refine the presence of an infiltrative cardiomyopathy versus other causes of increased wall thickness. The most clinically important types of amyloid heart disease are transthyretin (ATTR) and light chain (AL) amyloidosis. The workup to differentiate these disorders includes a gammopathy panel to screen for the presence of potentially amyloidogenic light chains (serum and urine electrophoresis WITH immunofixation and serum free light chains), and cardiac scintigraphy with Technetium-99m-labeled bone-seeking tracers (PYP, DPD, etc.) to identify cardiac aTTR infiltration if the gammopathy panel is unrevealing. There is still a role for endomyocardial biopsy in the diagnosis of cardiac amyloidosis! All patients in whom there is concern for cardiac amyloidosis and gammopathy panel indicates the presence of monoclonal light chains should have a biopsy to obtain a tissue diagnosis of likely AL amyloidosis. Alternatively, an endocardial biopsy may prove valuable in patients who have confusing phenotypic features between amyloid types, such as a patient with abnormal monoclonal protein and positive PYP imaging. Be suspicious of heart failure patients that do not tolerate typical medications that lower heart rate. In the restrictive cardiomyopathy of cardiac amyloidosis, patients are reliant on higher heart rates to compensate for the inability to augment stroke volume. Be suspicious of amyloidosis in patients with recurrent left atrial thrombi despite anticoagulation. Show notes CardioNerds Cardiac Amyloid, updated 1.20.21 1. What is cardiac amyloidosis and how common is it? Cardiac amyloidosis is adisorder caused by misfolding of proteins into insoluble forms which are deposited into extracellular spaces of the heart, commonly causing a stiff and thick heart with progressive diastolic dysfunction with restrictive hemodynamics and ensuing heart failure. The two most common types of amyloid protein that affect the heart are transthyretin (ATTR) and light chain (AL).