The Burden of Heart Failure in Cardiac Intensive Care Unit: A Prospective 7 Years Analysis

AIMS: The profiles of patients at cardiac intensive care units (CICU) have evolved towards a patient population with an increasing number of co-morbid medical conditions and acute heart failure (HF). The current study was designed to illustrate the burden of HF patients admitted to CICU, and evaluate patient characteristics, in-hospital course and outcomes of CICU patients with HF compared with patients with acute coronary syndrome (ACS). METHODS AND RESULTS: A prospective study including all consecutive patients admitted to the CICU at a tertiary medical centre between 2014 and 2020. The main outcome was a direct comparison between HF and ACS patients in processes of care, resource use, and outcomes during CICU hospitalization. A secondary analysis compared ischaemic versus non-ischaemic HF aetiology. Adjusted analysis evaluated parameters associated with prolonged hospitalization. The cohort included 7674 patients with a total annual CICU admissions of 1028-1145 patients. HF diagnosis patients represented 13-18% of the annual CICU admissions and were significantly older with higher incidence of multiple co-morbidities compared with patients with ACS. HF patients also required more intensive therapies and demonstrated higher incidence of acute complications as compared with ACS patients. Length of stay at the CICU was significantly longer among HF patients compared with patients with ACS (either STEMI or NSTEMI) (6.2 ± 4.3 vs. 4.1 ± 2.5 vs. 3.5 ± 2.1, respectively, P < 0.001). HF patients represented a disproportionately higher amount of total CICU patient days during the study period, as the total length of hospitalization of HF patients was 44-56% out of the total cumulative days in CICU of patients with ACS every year. In hospital mortality rates were also significantly higher among patients with HF compared with STEMI or NSTEMI (4.2% vs. 3.1% vs. 0.7%, respectively, P < 0.001). Despite several differences in baseline characteristics between patients with ischaemic versus non-ischaemic HF, which can be attributed mainly to disease aetiology, hospitalization length and outcomes were similar among the groups regardless of HF aetiology. In multivariable analysis for the risk of prolonged hospitalization in the CICU adjusted to potential significant co-morbidities associated with poor outcomes, HF was found to be an independent and significant parameter associated with the risk of prolonged hospitalization with an OR of 3.5 (95% CI 2.9-4.1, P < 0.001). CONCLUSIONS: Patients with HF in CICU have higher severity of illness with a prolonged and complicated hospital course, all of which can substantially increase the burden on clinical resources.