Long-term outcomes of cardiogenic shock survivors: a contemporary retrospective analysis from a tertiary center

Abstract Background Cardiogenic shock (CS) is a complex syndrome that still portends a dismal short-term prognosis. However, in patients that survive the initial admission and are later discharged, the long-term prognosis remains ill-characterized. Aim We aimed to describe the long-term morbidity and mortality outcomes of patients surviving the index admission for CS. Methods Retrospective analysis of all consecutive patients admitted to a cardiac intensive care unit (CICU) between December 2016 and December 2022 with a diagnosis of CS. All etiologies were included and further categorized as: acute myocardial infarction (AMI-CS), acute-on-chronic heart failure (HF-CS) and secondary causes [(S-CS): myocarditis, arrhythmic storm, acute pulmonary embolism, among others]. Our primary endpoint was defined as all-cause death, conditional to being discharged alive. Secondary endpoints comprised heart transplant, durable left ventricular assist device (LVAD) implantation, implantable cardioverter-defibrillator (ICD) insertion and hospital readmission during follow-up. Results A total of 208 patients were included [median age 68 years (IQR 57-80), 66% males, mean Charlson comorbidity index 4±3], of whom 52% (n=108) had AMI-CS, 27% (n=56) HF-CS and 21% (n=44) S-CS. During the index admission, mean SAPS II score was 49±18 and most patients were in SCAI-C (66%, n=137) stage. Organ support in the form of invasive mechanical ventilation, renal replacement therapy or temporary mechanical circulatory assist devices was necessary in 62% (n=129), 27% (n=56) and 26% (n=55) of patients, respectively. 53% of patients (n=110) survived the index admission [median CICU length of stay 8 (IQR 3-15) days; median hospital length of stay 13 (IQR 4-25) days]. At discharge, mean left ventricular ejection fraction was 38±16% and 28% (n=26) of patients underwent ICD implantation. Median follow-up after discharge was 679 (IQR 373-1056) days, with 4 (4%) patients lost to follow-up. Overall mortality was 22% (n=24) and was numerically higher for AMI-CS when compared to HF-CS and S-CS (9% vs 7% vs 6% respectively, p=0.640). Secondary endpoint analysis showed that 10% (n=11) had a heart transplant, 2% (n=2) received a durable LVAD, 9% (n=10) received an ICD and 26% (n=28) were re-hospitalized during that period. Conclusions Although the long-term mortality of patients discharged alive after the index admission for CS is not overwhelming, one in every four will be readmitted and a small proportion will be eligible for advanced heart failure therapies. Healthcare strategies to improve the morbidity and mortality of many CS survivors should be devised.