Clinical Outcomes of Patients with Ischemic Cardiogenic Shock Supported by Impella: Impact of Target Lesion in Right Ventricular vs. Left Ventricular Related Infarction

Background
Cardiogenic shock (CS) resulting from ischemic events such as acute myocardial infarction (AMI) represents a critical condition with high mortality rates, despite advanced treatment options. Mechanical circulatory support (MCS) devices, particularly the Impella, are increasingly used in CS management. While left ventricular myocardial infarction (LVMI) is commonly supported by Impella, data on its effectiveness in right ventricular myocardial infarction (RVMI) is limited. This study aims to analyze the clinical outcomes associated with right-sided and left-sided infarctions in patients undergoing Impella-supported CS.

Methods
We conducted a retrospective study on 171 patients with ischemic CS treated at the University Hospital of Düsseldorf between 2015 and 2021. Patients were categorized into right and left ventricular infarction groups based on the infarct site. Key data, including patient demographics, comorbidities, and clinical characteristics, were extracted and analyzed to determine 30-day survival and hospital stay duration.

Results
In this study of 171 patients with ischemic cardiogenic shock (CS) supported by the Impella device, 21.6% had right ventricular myocardial infarction (RVMI) and 78.4% had left ventricular myocardial infarction (LVMI). Baseline characteristics, including age, gender, and comorbidities, showed no significant differences between groups.

Thirty-day survival was significantly lower in the RVMI group (35.1%) compared to the LVMI group (56.7%, p = 0.020). Kaplan-Meier analysis confirmed a poorer survival probability for RVMI patients (Log-Rank p = 0.0307). Hospital stays were shorter for RVMI patients (median 5 days) versus LVMI patients (11 days), likely due to higher mortality rather than quicker recovery.

Duration of mechanical circulatory support (MCS) was similar between groups (median of 2 days). Post-procedure hemodynamic values and blood markers were comparable between groups. Additionally, LVMI patients treated during regular hours had better outcomes than those treated off-hours (p = 0.031).

Conclusion
The findings highlight a disparity in survival outcomes between right- and left-sided infarctions in Impella-supported CS. This suggests a need for caution when employing pVADs in patients with right-sided infarctions, as the device primarily supports left ventricular function. Future studies should focus on optimizing support strategies for right-sided CS to enhance patient survival and treatment efficacy.