Cardiac amyloidosis

Abstract

Systemic amyloidosis comprises an uncommon group of disorders caused by the extracellular deposition of misfolded proteins in various organs. Cardiac amyloid deposition, causing an infiltrative/restrictive cardiomyopathy, is a frequent feature of amyloidosis and a major determinant of survival. It may be the presenting feature of the disease or may be identified while investigating a patient presenting with other organ involvement. The need for a high index of suspicion and the critical importance of precise biochemical typing of the amyloid deposits is paramount in light of recent therapeutic advances that can significantly improve prognosis. Most cases of cardiac amyloidosis are of either transthyretin type, which may be acquired in older individuals or inherited in younger patients, or acquired monoclonal immunoglobulin light chain (AL) type. This article aims to review recent developments in diagnosis and management of cardiac amyloidosis.

Chronic Diarrhea as the Presenting Feature of Amyloidosis with Multiple Myeloma: A Case Report Diagnosed by a Myocardial Biopsy

“…Because the thickening of ventricular walls in amyloidosis is due to myocardial amyloid deposition rather than hypertrophy, the ECG voltages tend to decrease as the disease progresses. Low voltage on ECG (defined as all limb leads <5 mm in height) is found in a high proportion of patients with AL Intern Med Advance Publication DOI: 10.2169/internalmedicine.6038-20 amyloidosis (16). Thick-walled heart on echocardiogram but with a normal or low voltage ECG remains a diagnostic hallmark of amyloidosis, with high sensitivity (72-79%) and specificity (91-100%) (17).…”

Diagnostic imaging of cardiac amyloidosis

“…Cardiac amyloidosis typically manifests with signs and symptoms of heart failure and poor exercise tolerance owing to low cardiac output 26 . These symptoms are often accompanied by hypotension, which complicates heart failure management.…”

Analysis of Cardiac Amyloidosis Progression Using Model-Based Markers

“…However, as the pressure measurements are invasive, this information is not available from in vivo studies. On the other hand, the literature suggests that all amyloidosis patients have increased wall thickness and higher pressure compared with normal subjects (Kholova and Niessen, 2005;Quarta et al, 2012;Martinez-NaharrO et al, 2018). Hence, we assume P ED is proportional to scaled LV wall volume as follows:…”

“…The left ventricle (LV) with amyloid becomes firm, rubbery and stiff, similar to hypertrophic cardiomyopathy (Kholova and Niessen, 2005). Further, the ventricular wall is thickened (Carroll et al, 1982;Kholova and Niessen, 2005;Quarta et al, 2012;Martinez-NaharrO et al, 2018), particularly in the interventricular septum (Frenzel et al, 1986), but the ventricular cavity does not dilate much (Kholova and Niessen, 2005). Hence, the functional defect in amyloidosis is associated to the "stiff heart" syndrome, with the LV end-diastolic pressure rising to at least 10 mmHg higher than normal subjects (Chew et al, 1975;Swanton et al, 1977).…”