Absence of Heart Failure in Severe Cardiac and Autonomic Amyloidosis: The Essential Role of Sympathetic Activation and Venous Tone in the Development of the Congestive Heart Failure Syndrome

The case study of a 66-year-old man with primary light-chain (AL) amyloidosis highlighted the essential role of sympathetic activation and venous tone in the development of congestive heart failure. Despite severe cardiac amyloidosis and diastolic dysfunction, the patient did not exhibit typical heart failure symptoms, such as shortness of breath or orthopnea, due to his severe autonomic neuropathy, which impaired sympathetic control and reduced venous tone. This resulted in low intracardiac filling pressures and absence of heart failure symptoms. The study emphasized that sympathetic nervous system activation and venous tone are crucial for the manifestation of heart failure symptoms, suggesting that reducing neurohormonal activation could be a key therapeutic target in treating congestive heart failure.