Safety and efficacy of levosimendan in patients with cardiac amyloidosis

Background: Patients with cardiac amyloidosis (CA) often experience heart failure (HF) episodes. No evidence is available on inotropic therapy. This study aims to fill this gap by examining the safety and efficacy of levosimendan. Methods: We retrieved all HF patients receiving >= 1 levosimendan infusion from 2013 to 2023. CA patients were matched with HF patients without CA (controls) based on sex, age, and left ventricular ejection fraction (LVEF). The response to levosimendan was measured as changes in daily urinary output, body weight, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and estimated glomerular filtration rate (eGFR). Results: CA patients (median age 77 years, 73% men, 59% with ATTR-CA) and controls were compared. Levosimendan infusion was stopped because of hypotension in 2 cases with CA and (in 1 case) worsening renal function, and in 2 controls because of ventricular tachycardia episodes and (in 1 case) hypotension. CA patients showed a trend toward increased daily urinary output (p = 0.078) and a significant decrease in body weight (p < 0.001), without significant changes in NT-proBNP (p = 0.497) and eGFR (p = 0.732). Both CA patients and controls displayed similar changes in urinary output, weight, and eGFR, but NT-proBNP decreased more significantly among controls (p < 0.001). No differences were noted in rehospitalization rates, but CA patients experienced higher mortality at 6 and 12 months (p = 0.003 and p = 0.001, respectively). Conclusions: Levosimendan appears safe for CA patients needing inotropic support. The diuretic response and weight decrease during hospitalization were comparable between CA patients and matched HF patients, despite the greater mortality of CA patients after discharge.