Abstract 13087: Are All Patients Equal in Response to Intra-Aortic Balloon Counterpulsation?

Background: Intra-Aortic Balloon Counterpulsation (IABC) with a 50 cc (MEGA 50™) balloon catheter is associated with an average increase of 0.5- 0.7 liters/min in cardiac output. However, some patients (pts) have a much more dramatic response. We retrospectively analyzed our single center tertiary care experience with 150 consecutive pts undergoing IABC. Methods: Chart review for demographic, procedural, and hemodynamic data was collected for 150 pts of whom 64 had both pre and 4 hour post IABC hemodynamic measurements. The responder (R) group was defined by any positive change in cardiac output (CO) and cardiac index (CI) between baseline prior to IABC and 4 hours post initiation. Non-responders (NR) were defined as those with a decline in CO or no change. Results: IABC with a 50 cc balloon was associated with a significant improvement in CO of 0.7 L/min for the overall cohort (Pre-IABC mean CO 3.9±1.4 vs post 4.6 ±1.6 L/Min, paired t-test p=.0004). There were 38 pts in the R group (60 %) and 26 in the NR group. The CO / CI post-IABC improved significantly: CO 3.5±1.3 to 5.0±1.7 L/Min and CI 1.8±0.6 vs 2.6±0.7 L/min/M 2 ) (p<0.0001). For NR pts, CO dropped from 4.5±1.3 to 3.9±1.2 L/Min (p<0.0001) and CI from 2.2±0.6 to 2.1±0.5 L/min/M 2 (p=0.1). Interestingly, systemic vascular resistance varied significantly between groups (R: 1568±657 vs NR 1218±461 (dyne*sec)/cm 5 (p=0.02). Nominal logistic regression identified pre-IABC CO as a significant predictor of response. Conclusion: Among a cohort of pts receiving IABC, there appears to be a binary response with “responders” augmenting CO by 1.5 L/min which is close to that provided by percutaneous ventricular assist catheters such as Impella. Patients with lower pre-IABC CO and higher SVR appear to have the most favorable response to IABC. This binary response may have influenced prior neutral clinical outcome trials of IABC.