Predictors of Hemodynamic Response to Intra-Aortic Balloon Pump Therapy in Patients with Acute Decompensated Heart Failure and Cardiogenic Shock

Abstract

Introduction There is renewed interest in the utility of the intra-aortic balloon pump (IABP) for short-term and durable support in patients with chronic systolic heart failure (HF) who present with acute decompensation and cardiogenic shock (CS). However, the clinical characteristics of IABP-responders and non-responders remain incompletely defined. We sought to identify predictors of early IABP response to guide optimal use of IABP therapy in this population. Methods We retrospectively analyzed the records of chronic systolic HF patients who presented at our institution between 2011-2018 with acute decompensated HF with hemodynamic evidence of CS and underwent IABP placement. IABP-responder was defined as having an immediate increase in cardiac output (CO) and an immediate decrease in mean pulmonary artery pressure (MPAP) above the median values of the cohort. Logistic regression was used to identify predictors of hemodynamic response. Results During the study period, 218 chronic systolic HF patients underwent IABP insertion for acute decompensation with CS. The mean age was 59.4 ±13.4 years, 79.8% were men, and 38.5% had ischemic cardiomyopathy (ICM). The average hemodynamic response to IABP in the whole cohort was a CO increase of 0.57 ±0.85L/min and a MPAP reduction of 5.1 ±7.6mmHg; IABP-responders had a CO increase of 1.21 ±0.87L/min and a MPAP reduction of 12.1 ±5.9mmHg (figure). Univariable predictors of IABP-response were ICM, presence of severe mitral regurgitation, baseline heart rate, elevated MPAP, and elevated systemic vascular resistance (SVR). Following multivariable logistic regression, independent predictors of IABP-response were elevated baseline SVR (OR 2.05, 95% CI 1.01 - 4.17; p=0.047) and elevated MPAP (OR 2.47, 95% CI 1.23 - 5.00; p=0.01). MPAP reduction decreased the odds of death or need for escalation to another short-term circulatory support device while CO increase did not [OR 0.52 (0.28 - 0.97; p=0.04) vs. 0.83 (0.45 - 1.54; p=0.56)]. Conclusions A subset of chronic systolic HF patients had a robust hemodynamic response to IABP insertion with CO augmentation and MPAP reduction. Elevated baseline SVR and MPAP are predictors of robust response following device insertion. These parameters may be used to identify patients who may respond favorably to IABP counterpulsation therapy.