Long-term clinical outcomes and patterns of follow-up after cardiogenic shock: insights from an advanced heart failure referral center registry

Abstract Background Inpatient mortality of patients with cardiogenic (CS) has been reported as high as 50%. Those who present in CS are at high risk of having recurrent admissions to hospital or requiring advanced heart failure (HF) therapies. The Toronto General Hospital (TGH) is a quaternary cardiac center, providing mechanical circulatory support (MCS) and heart transplantation (HT), serving as a regional CS transfer hub for a population of over 8 million people. While inpatient management of CS patients has been studied extensively, there is little data on where or how these patients are followed after their discharge. We aimed to determine the long-term clinical outcomes and nature of follow up after a CS admission. Methods This was a retrospective cohort study of CS patients admitted to TGH between 2014 and 2023. We collected data regarding survival to discharge and the type of follow up patients received after their index CS admission. Survival was compared using Kaplan-Meier methods. Results 1582 patients were admitted during the study. The mean age was 59.9 + 16.1 years, including 474 (30.0%) females and 335 (21.2%) patients with acute myocardial infarction CS. In-hospital mortality was 32.4%, with a further 17 (1.8%) patients transferred to palliative care during their index CS admission. After excluding patients who underwent heart transplantation (HT) or durable MCS implant, 679 patients were discharged alive, with median follow-up of the 307 (range 0 – 3436) days. Overall mortality was 57.0%. Among discharged patients, 396 (56.8%) were followed at the regional hub hospital. A further 54 (8.0%) patients were followed by a cardiology provider at a referring community center. A total of 202 (29.7%) patients did not have outpatient follow up arranged at the time of their discharge and no details of further care were available. Median survival during follow-up was higher among patients with confirmed follow-up at the time of their discharge, but not statistically significant (1798 vs 1775 days, p=0.067). There was a significant survival benefit among CS patients followed at a heart function clinic compared with those who were not, (1821 vs. 1775 days, p= 0.020). In terms of candidacy for advanced therapies, having outpatient follow up was associated with receiving durable MCS or HT (6.3% vs. 0.5%, p=0.003). Conclusion Despite advances in the management of CS, overall mortality remains high at 57.0%. Follow-up after CS admission is of essential importance- both in improvement of long-term outcomes, and access to advanced heart failure therapies. There was a survival benefit among patients who were followed in a specialized heart function clinic. Additionally, having outpatient follow up was significantly associated with receiving advanced therapies. Further research is needed to identify the barriers to accessing post discharge follow-up care.