Differential responses to larger volume intra-aortic balloon counterpulsation: Hemodynamic and clinical outcomes

Abstract

Objectives: Examine hemodynamic and clinical correlates of use of an intra-aortic balloon pump catheter in a single center.

Background: The intra-aortic balloon pump catheter (IABC) has been used for 50 years but the clinical benefit is still debated. We reviewed 76 patients with right heart catheter measurements prior to IABC to assess response and outcomes.

Methods: All patients who received IABC with a 50cc balloon for at least 1 hour were included in this retrospective chart review study. Demographics, comorbidities, lab values, and hemodynamic parameters were recorded at baseline and 15 h postinsertion.

Results: Seventy-six patients had paired measurements of cardiac output. 60 patients had a higher cardiac output with IABC treatment (responder group) and 16 did not (nonresponders). In the 60 patients in the responder group, cardiac output and index significantly increased from baseline 3.6 ± 1.3 L/min to 5.2 ± 1.8 L/min, and 1.8 ± 0.5 L/min/m² to 2.6 ± 0.8 L/min/m² respectively following IABC placement (P < 0.0001 for both comparisons). Various hemodynamic variables were examined and the best predictor of response to IABC was a cardiac power index of 0.3 or less. Regardless of response, in hospital survival was similar between groups.

Conclusions: The majority of patients improve their cardiac output with IABC but survival was unchanged. Further work into the pathophysiology of cardiogenic shock is needed.

Keywords: cardiogenic shock; counterpulsation; mortality; systolic heart failure.

Figure 1

Panel A: The change in cardiac output between baseline and timepoint A is illustrated with medians and intraquartile ranges graphically illustrated (for both the “responders” and “nonresponders”). Panel B: A parallel plot illustrating the change in cardiac output between baseline and timepoint A showing a line for each patient (for both the “responders” and “nonresponders”). Panel C: A scatterplot illustrating the relationship between baseline cardiac index and the cardiac index post‐ IABC treatment. The vertical line is at 2.2 L/min/M², which is a definition of cardiogenic shock. Panel D: A scatterplot illustrating the relationship between baseline cardiac power index and the cardiac power index post‐ IABC treatment. The vertical line is at 2.2 L/min/M², which is a definition of cardiogenic shock

Figure 2

Kaplan‐Meier plot of survival following IABC placement, separated according to treatment (bridge to transplant, bridge to recovery, bridge to mechanical circulatory support or no escalation). The patients who were bridged to durable mechanical circulatory support or heart transplant had 100% survival over the period of observation

Figure 3

Bar graph illustrating the percentage of patients who transitioned to higher levels of support, recovered or were not transitioned from IABC therapy

Figure 4

Kaplan‐Meier plot of survival divided based on “responder”/“nonresponder” status

Figure 5

Kaplan‐Meier plot of survival divided based on whether the IABC was placed for a diagnosis of cardiogenic shock or not