Clinical profile and outcome of cardiac amyloidosis in a Spanish referral center

Abstract

Introduction and objectives: Cardiac amyloidosis (CA) is produced by amyloid fiber deposition in the myocardium. The most frequent forms are those caused by light chains (AL) and transthyretin (ATTR). Our objective was to describe the diagnosis, treatment and outcomes of CA in a specialized Spanish center.

Methods: We included all patients diagnosed with CA in Hospital Universitario Puerta de Hierro Majadahonda from May 2008 to September 2018. We analyzed their clinical characteristics, outcomes, and survival.

Results: We included 180 patients with CA, of whom 64 (36%) had AL (50% men; mean age, 65±11 years) and 116 had ATTR (72% men; mean age 79±11 years; 18 with hereditary ATTR). The most common presentation was heart failure in both groups (81% in AL and 45% in ATTR, P <.01). Other forms of presentation in ATTR patients were atrial arrhythmias (16%), conduction disorders (6%), and incidental finding (6%); 70 patients (40%), had a previous alternative cardiac diagnosis. Diagnosis was noninvasive in 75% of ATTR patients. Diagnostic delay was higher in ATTR (2.8±4.3 vs 0.6±0.7 years, P <.001), but mortality was greater in AL patients (48% vs 32%, P=.028). Independent predictors of mortality were AL subtype (HR, 6.16; 95%CI, 1.56-24.30; P=.01), female sex (HR, 2.35; 95%CI, 1.24-4.46; P=.01), and NYHA functional class III-IV (HR, 2.07; 95%CI, 1.11-3.89; P=.02).

Conclusions: CA is a clinical challenge, with wide variability in its presentation depending on the subtype, leading to diagnostic delay and high mortality. Improvements are needed in the early diagnosis and treatment of these patients.

Keywords: Amiloidosis cardiaca; Amiloidosis por cadenas ligeras; Amiloidosis por transtiretina; Amyloid light-chain amyloidosis; Cardiac amyloidosis; Prognosis; Pronóstico; Transthyretin; Transthyretin amyloidosis; Transtiretina; Tratamiento; Treatment.