Outcome of patients with cardiac amyloidosis admitted to an intensive care unit for acute heart failure

Abstract

Background: The outcome of cardiac amyloidosis (CA) has been reported mainly in stable populations; limited data are available in patients referred for acute heart failure (AHF) to an intensive cardiac care unit (ICCU). Aims: To address the characteristics and outcomes of patients with confirmed CA admitted to an ICCU for AHF and then to identify the predictors of evolution to cardiogenic shock. Methods: All patients with CA referred to an ICCU for AHF between 2009 and 2015 were included. The clinical endpoint was 3-month death. Data from the population with cardiogenic shock, obtained in a stable haemodynamic state, were matched with data from a control group to determine predictors of evolution to cardiogenic shock. Results: Among the 421 patients followed for CA in our expert centre, 46 patients (mean age: 64 ± 14 years; 65% light-chain [AL] CA) were referred to the ICCU for AHF (n = 26 with cardiogenic shock). At 3 months, death occurred in 24 (52%) patients, mostly in the cardiogenic shock group (n = 21/26, 81%). Most deaths occurred 5 days [interquartile range 3–9 days] after catecholamine infusion and 50% occurred in patients aged < 65 years. The majority of deaths were reported in patients with AL CA (n = 19/24, 79%). Independent variables associated with in-hospital mortality were cardiogenic shock and uraemia level. N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) concentration obtained in a stable haemodynamic state was the only predictor of short-term evolution to cardiogenic shock (odds ratio: 8.7, 95% confidence interval: 2.2–34.6), with an optimal cut-off of 4040 pg/mL (sensitivity = 92%; specificity = 81%). Conclusions: The study confirms the dramatic mortality associated with CA when presenting as cardiogenic shock and underlines the limited efficiency of conventional treatments. Given the rapid occurrence of death in a young population, an alternative strategy to dobutamine support should be investigated in patients with elevated NT-proBNP concentration.