Clinical impact of the prophylactic use of intra-aortic counterpulsation in high-risk patients undergoing myocardial revascularization

Introduction

The use of the intra-aortic balloon (IAB) has been well established in the clinical management of patients with problems such as refractory myocardial ischemia, cardiogenic shock, and difficulty in weaning from extracorporeal circulation (ECC). However, the literature lacks evidence supporting the 'prophylactic' use of the IAB in high-risk patients undergoing myocardial revascularization (MR).

Objective

To assess the clinical outcome of surgical high-risk (HR) patients undergoing MR, who received a 'prophylactic' IAB.

Methods

A prospective and observational study of a population undergoing elective MR. High-risk patients were defined as those having severe LV dysfunction (EF <35%) on TT ECHO and/or lesion in the left main coronary artery (obstruction >50% of the luminal diameter). The sample was divided into two groups: Group 1 (G1) with 'prophylactic' IAB, and Group 2 (G2) without IAB. The influence of the following variables on clinical outcome was assessed: use of amines; fluid balance (FB) in the perioperative period (PER); time of ECC, anoxia, and mechanical ventilation (MVT); ICU length of stay (ICULOS); hospital length of stay (HLOS); complications of the procedure; and death.

Results

G1 comprised 16 patients (87.5% men) with a mean age of 61.6 (SD 8.6) years, and G2 comprised 39 patients (87.1% men) with a mean age of 56 (SD 8.0) years (P = not significant). No difference was observed between the groups regarding the other base variables, except for BMI (P = 0.00035). In regard to clinical outcome, only FB in the PER (G1 median 1695 ml, interquartile interval [IIQ] 923–1865; G2 median 2061 ml, IIQ 1257–2860, P = 0.03) and MVT (G1 median 11.5 hours, IIQ 7–26 hours; G2 median 8 hours, IIQ 5–12 hours) had statistical significance. No significance was observed regarding the use of amines, time of ECC, ICULOS, HLOS, and death. No complications inherent to IAB use were observed.

Conclusion

The 'prophylactic' use of the IAB showed no benefit regarding morbidity and mortality in the population studied. The greater blood volume replacement and prolonged MVT emphasize the need for care when indicating this procedure.