Hereditary Transthyretin Amyloidosis: How to Differentiate Carriers and Patients Using Speckle-Tracking Echocardiography.

BACKGROUND: Hereditary transthyretin amyloidosis is a rare disease caused by transthyretin (TTR) gene mutations. The aim of our study was to identify early signs of cardiac involvement in patients with a TTR gene mutation in order to differentiate carriers from patients with neurological or cardiac disease. METHODS: A case-control study was carried out on 31 subjects with the TTR mutation. Patients were divided into three groups: 23% with cardiac amyloidosis and polyneuropathy (group A), 42% with only polyneuropathy (group B) and 35% carriers (group C). Speckle-tracking echocardiography (left-ventricular global longitudinal strain-GLS, atrial stiffness) was performed in all patients. The apical/basal longitudinal strain ratio (SAB) and relative apical sparing (RAS) were assessed in all subjects. RESULTS: Analyzing groups C and B, we only found a significant difference in the SAB (p-value 0.001) and RAS (p-value 0.039). These parameters were significantly more impaired in group A compared to group B (SAB p-value 0.008; RAS p-value 0.002). Also, atrial stiffness was significantly impaired in groups A and B compared to group C. CONCLUSIONS: Our study suggests the diagnostic role of the SAB and RAS in cardiac amyloidosis. The SAB and RAS showed a gradual increase from carriers to patients with neurological and cardiac diseases. Thus, these parameters, in addition to atrial stiffness, could be used to monitor carriers. More extensive data are needed.

Effectiveness and Safety of Oral Anticoagulants in Cardiac Amyloidosis: Lights and Shadows.

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy characterized by extracellular deposition of mis-folded proteins called amyloid. Cardiac complications of CA are several: heart failure, aortic valve stenosis, thromboembolism, conduction disorders, atrial fibrillation, and ventricular arrhythmias. Atrial dysfunction is common in CA patients. Several evidences suggest to anticoagulated patients with CA in atrial fibrillation independently from CHA2DS2VaSC score. Considering the high thromboembolic risk in CA patients, anticoagulant therapy should be considered also in CA patients in sinus rhythm, when the atria are enlarged and dysfunctional, and the bleeding risk is low. Unfortunately indication to anticoagulation in patients with CA in sinus rhythm still remains a gray zone. Also drug-drug interactions should be considered in patients with CA. In this review, we will evaluate the effectiveness and safety of oral anticoagulants in CA patients, and we will propose a practical guide for management of anticoagulant therapy in CA patients.