Acute-on-chronic heart failure leading to cardiogenic shock: any role for intra-aortic balloon pump? Results from a multicenter retrospective data collection

Abstract

Abstract Funding Acknowledgements None. Background Intra-aortic balloon pump (IABP) implantation has been significantly reduced since IABP-SHOCK II trial did not show any clinical benefit in acute myocardial infarction (AMI)-related cardiogenic shock (CS)(1). For a long time, AMI has been recognized as the first cause of CS; however, in the last years, acute-on-chronic heart failure (HF)-CS has become predominant. We hypothesized that in HF-CS population the IABP may decrease mortality having a role in decreasing left ventricular afterload and improving peripheral perfusion(2). Purpose To investigate whether, in this phenotypical category of cardiogenic shock, IABP could improve 28-days mortality. Methods Multicenter retrospective observational study including adult HF-CS patients admitted in cardiac or general intensive care units in 3rd level centers. Hemodynamic variables before (T0) and after IABP implantation (T1), pharmacological support and outcome data were collected. Independent samples t-test was applied to assess any difference between IABP and non-IABP group; Kaplan-Meier and Cox’s regression (forward stepwise method) were performed as survival analysis on 28-days mortality. Results 160 patients (35.6% female, 61 [47-74] years-old) were included from three centers; overall mortality was 42.5%. 50% received IABP support; amongst IABP patients, 24 received further MCS with VA-ECMO (p <0.001) and 4 with Impella (p 0.120). Patients’ baseline characteristics are shown in Figure 1-A. IABP patients had lower 28-days mortality. Patients who received IABP were younger, had lower systolic blood pressure (SBP), pulse pressure (PP) and lactate levels at T0. In reference to catecholaminergic drugs, patients supported with IABP had lower norepinephrine doses and vasoactive inotropic score (VIS) at baseline. After IABP implantation, no significant difference between the two groups in the time variation of these parameters was observed (Figure 1-B). Survival analysis graphs are shown in Figure 2. At Cox’s regression, a significant effect on 28-days mortality was found for IABP (HR 0.510 [0.293-0.887], p 0.017), SCAI classification-stage D (HR 2.582 [1.315-5.072], p 0.006), VIS-T0 above 15 (HR 2.348 [1.407-3.921], p 0.001) and SBP-T0 above 95 mmHg (HR 1.361 [1.016-1.823], p 0.039); no significant association was found for age above 61 years (overall median value) (p 0.091), mechanical ventilation (p 0.367), PP-T0 (0 0.081) and lactate-T0 (p 0.227). Conclusions Considering the specific pathophysiology of HF-CS, IABP may have a role in reducing mortality. These retrospective data need to be validated and compared with those deriving from ongoing randomized controlled trials(3).