AN ANALYSIS OF INDICATIONS, TIME OF INITIATION AND MORTALITY IN ADULT CARDIAC SURGICAL PATIENTS WITH INTRA-AORTIC BALLOON PUMP SUPPORT

Abstract

Objective: To determine the frequency, indications, time of initiation and outcome of intra-aortic balloon
pump (IABP) therapy in adult cardiac surgical patients over the period of one year in Queen Alia Heart
Institute (QAHI). Methods: From January 2009 to January 2010, 1872 consecutive adult open heart
surgical procedures were performed. This included 1361 isolated coronary artery bypass grafting (CABG)
procedures, 359 isolated valve procedures (one or more valves), 112 combined CABG & valve procedures
and 40 other procedures (ASD, VSD, cardiac tumors). Patients were divided into three groups in relation
to the time of insertion of intra-aortic balloon pump and initiation of counter-pulsation: Pre-operative,
intra-operative and postoperative groups. Mean age of patients was 59 years (range, 41 to 78 years) and 68
% of patients were males. In hospital mortality for each group was compared at 7 days and 30 days. Chisquare
test was used to investigate the relationship between the mortality rate at 7 days and 30 days with
other factors. The result was considered significant if the p-value was less than 0.05. Results: Intra-aortic
balloon pump support was used in 121 patients (out of 1872 patients), which constituted 6.46 % of all
adult cardiac surgical patients. Weaning from cardiopulmonary bypass (CPB) was the most common
indication of IABP use (66.9%). Preoperative insertion and initiation of intra-aortic balloon pump
counterpulsation had significant lower 7 day mortality than the intra-operative and post-operative uses (pvalue
=0.022). At 30 days the mortality was least in the intra-operative group and most in the postoperative
group, the p-value was not significant (p-value=0.087). The use of intra-aortic balloon was
associated with less mortality for isolated coronary artery bypass grafting (CABG) than the combined
(CABG + valve) surgeries or isolated valvular surgeries at 7 and 30 days. The p-value was significant at 7
days (p-value=0.014), and was also significant at 30 days (p-value=0.029). Female patients who had IABP
support had higher mortality rates than male patients at 7 days and 30 days. Results were statistically not
significant when relationship between gender and mortality at 7 days was investigated (p-value=0.114)
and between gender and 30 days mortality (p-value=0.081). Conclusions: Weaning from cardiopulmonary
bypass (CPB) is the most common indication for counter-pulsation. Pre-operative prophylactic uses were
found to be less common and were associated with lower mortality rates. Therefore, earlier IABP therapy
as part of surgical strategy in high risk patients may help improve the outcome. Higher mortality rates
were observed in patients who had IABP support initiated post-operatively, in female patients or in
isolated valve(s) procedures. Our results are compared favourably with others reported in the literature.
Key words: Intra-aortic balloon pump (IABP), cardiac surgery, cardiopulmonary bypass (CPB), mortality,
coronary artery bypass grafting (CABG).