Diagnostic and prognostic value of cardiac imaging in amyloidosis

Abstract

Amyloidosis is an infiltrative disease caused by extracellular protein deposition that has accumulated a lot of scientific production in recent years. Different types of amyloidosis can affect the heart. Transthyretin amyloidosis and light chain amyloidosis are the two most common types of cardiac amyloidosis. These entities have a poor prognosis, so accurate diagnostic techniques are imperative for determining an early therapeutic approach. Recent advances in cardiac imaging and diagnostic strategies show that these tools are safe and can avoid the use of invasive diagnostic techniques to histological confirmation, such as endomyocardial biopsy. We performed a review on the diagnostic and prognostic implications of different cardiac imaging techniques in cardiac amyloidosis. We mainly focus on reviewing echocardiography, cardiac magnetic resonance, computed tomography and nuclear imaging techniques and the different safety measurements that can be done with each of them.

Carpal Tunnel Syndrome in Transthyretin Cardiac Amyloidosis: Implications and Protocol for Diagnosis and Treatment

“…Although CA caused by TTR deposition has a prevalence as low as 1.2% when CTS is absent, prevalence is as high as 5.5% when CTS is present [ 12 ]. Furthermore, TTR deposition has been shown to be increased in other soft tissue locations such as the lumbar canal resulting in lumbar spinal stenosis, bicep and quadricep tendon leading to atraumatic tendon rupture, and in the hand with subsequent Dupuytren’s contracture [ 13 ].…”

“…CA is the feared outcome of ATTR and a complete workup should be performed to guide early treatment and increase overall survival. Imaging studies are often performed first and show an invariably thickened left ventricular wall, a coexisting pericardial effusion, right ventricular wall thickening, and interatrial septal thickening [ 3 , 12 ]. One study added that clinical suspicion for CA should be strong when left ventricular hypertrophy exists in the absence of hypertension [ 3 ].…”

“…A common initial imaging test performed in the workup of ATTR-CA is a transthoracic echocardiogram (TTE). The non-invasive nature of TTE allows it to be more practical compared to the invasiveness of a myocardial biopsy [ 12 ]. When performed, thickness of 12 mm or more in the interventricular septum in the absence of alternative causes of left ventricular hypertrophy is a key finding characteristic of ATTR-CA [ 3 , 12 ].…”

“…The non-invasive nature of TTE allows it to be more practical compared to the invasiveness of a myocardial biopsy [ 12 ]. When performed, thickness of 12 mm or more in the interventricular septum in the absence of alternative causes of left ventricular hypertrophy is a key finding characteristic of ATTR-CA [ 3 , 12 ]. When TTR deposition progresses, a restrictive filling pattern can be seen with a conserved or slightly diminished ejection fraction [ 12 ].…”

“…When performed, thickness of 12 mm or more in the interventricular septum in the absence of alternative causes of left ventricular hypertrophy is a key finding characteristic of ATTR-CA [ 3 , 12 ]. When TTR deposition progresses, a restrictive filling pattern can be seen with a conserved or slightly diminished ejection fraction [ 12 ]. In addition to the use of TTE, an electrocardiogram (ECG) can show normal or low ECG voltage often discrepant with TTE findings, along with pseudo-infarcts and poor R wave progression [ 3 ].…”