Cardiogenic Shock in Idiopathic Dilated Cardiomyopathy Patients: Red Flag for Myocardial Decline

Abstract

Idiopathic dilated cardiomyopathy (IDCM) is one of the most common forms of nonischemic cardiomyopathy worldwide, possibly leading to cardiogenic shock (CS). Despite this heavy burden, the outcomes of CS in IDCM are poorly reported. Based on a large registry of unselected CS, our aim was to shed light on the 1-year outcomes after CS in patients with and without IDCM. FRENSHOCK was a prospective registry including 772 patients with CS from 49 centers. The 1-year outcomes (rehospitalizations, mortality, heart transplantation [HTx], ventricular assist devices [VAD]) were analyzed and adjusted on independent predictive factors. Within 772 CS included, 78 occurred in IDCM (10.1%). Patients with IDCM had more frequent history of chronic kidney failure and implantable cardioverter-defibrillator implantation. No difference was found in 1-month all-cause mortality between groups (28.2 vs 25.8%for IDCM and others, respectively; adjusted hazard ratio 1.14 [0.73 to 1.77], p = 0.57). Patients without IDCM were more frequently treated with noninvasive ventilation and intra-aortic balloon pump. At 1 year, IDCM led to higher rates of death or cardiovascular rehospitalizations (adjusted odds ratio 4.77 [95% confidence interval 1.13 to 20.1], p = 0.03) and higher rates of HTx or VAD for patients aged <65 years (adjusted odds ratio 2.68 [1.21 to 5.91], p = 0.02). In conclusion, CS in IDCM is a very common scenario and is associated with a higher rate of 1-year death or cardiovascular rehospitalizations and a more frequent recourse to HTx or VAD for patients aged <65 years, encouraging the consideration of it as a red flag for myocardial decline and urging for a closer follow-up and earlier evaluation for advanced heart failure therapies.

Keywords: cardiogenic shock; dilated cardiomyopathy; epidemiology; mortality; prognosis.