Rotational Mechanics of the Left Ventricle in AL Amyloidosis

Abstract

Both twisting and untwisting motions are increased in patients with AL systemic amyloidosis with no evidence of cardiac involvement while they are reduced in patients with evident amyloidosis cardiac involvement. This finding suggests that impaired LV relaxation induces a compensatory mechanism in the early phase of the disease, which fails in more advanced stage when both twisting and untwisting rates are reduced. The increase in LV rotational mechanics could be a marker of subclinical cardiac involvement.

Myocardial Deformation Imaging and Rare Cardiomyopathies with Hypertrophic Phenotype: A Review Focused on Fabry Disease, Friedreich Ataxia and Amyloidosis

“…14 The previously described speckled or granular appearance of the myocardium is not specific for CA. 14,37 The availability of some therapies for CA particularly for the early stages of the disease coupled with the very poor prognosis, particularly with AL amyloidosis, emphasizes the need for an early diagnosis of cardiac involvement. 38 Unfortunately, standard echocardiographic and Doppler techniques, including tissue Doppler analysis, do not allow the detection of CA at an early stage when therapy can be most effective.…”

“…Oxidative stress with cellular necrosis and interstitial fibrosis is probably due to a combination of chronic interstitial infiltration and acute toxic effect of circulating light chains. 14,37 Morphologically, progressive increase in biventricular wall thickness (rather than true hypertrophy) ensues with small or normal LV chamber size, dilated atria, often thickened interatrial septum and a pericardial effusion. 14 The previously described speckled or granular appearance of the myocardium is not specific for CA.…”

“…However impaired relaxation is not a specific finding, occurring with aging and in numerous pathological states. 14,[37][38][39] The subendocardial layer where longitudinally oriented fibers are predominantly located is primarily involved with the amyloid process leading to early and marked impairment of longitudinal function. This can be detected by Mmode, pulsed TDI and strain imaging demonstrating significant reduction in displacement, velocity and deformation values along the longitudinal plane.…”

“…Both transthyretinrelated amyloidosis have a better prognosis than AL amyloidosis. [35][36][37] Amyloid deposition occurs uniformly throughout the heart involving the myocardium, endocardium, pericardium, interatrial septum, conduction system, valves and coronary arteries. Oxidative stress with cellular necrosis and interstitial fibrosis is probably due to a combination of chronic interstitial infiltration and acute toxic effect of circulating light chains.…”

Recent advances in the imaging assessment of infiltrative cardiomyopathies

“…Twisting/untwisting motion involves both systolic and diastolic function and therefore would be altered in thickened ventricle as in cardiac amyloidosis. This was assessed in a study by Porciani and colleagues in 45 patients with AL amyloid and 26 control subjects 7. The AL patients were subgrouped into CA if LV wall thickness was ≥12 mm and non-CA (NCA) if LV thickness was ≤12 mm.…”