Investigation of acute systemic inflammatory response and myocardial injury after cardiac surgery in patients infected with human immunodeficiency virus

Abstract

Introduction: The immediate post-cardiopulmonary bypass (CPB) immune responses and organ injuries in immune- compromised patients remain poorly documented. We conducted a prospective clinical study to determine whether or not human immunodeficiency virus (HIV) seropositive patients generate higher acute systemic inflammatory response and suffer greater myocardial injury, compared to HIV seronegative patients.

Methodology: Sixty-one consecutive patients i.e. Thirty HIV seropositive patients and Thirty-one seronegative, undergoing elective cardiac valve(s) replacement were enrolled, over a period of nine months from a single center hospital, after informed consent was acquired. The C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR) were used as biomarkers of acute inflammatory response, and cardiac troponin I (cTnI) as a biomarker for measuring postoperative myocardial injury. Single tests were measured preoperatively and postoperatively, in both groups, and these were compared and correlated to perioperative events and CPB parameters.

Results: The mean age group was similar between the HIV seropositive and negative group (37.8 and 37.1 years, respectively). Preoperatively both groups had relatively equal CRP levels (p=0.388), ESR levels (p=0.817) and cTnI (p=0.489). The CPB events and durations were significantly different between the two groups, CPB duration (p=0.021). Other CPB events include, clamp aortic duration (p=0.026), CPB blood transfusion (p=0.013), CPB total urine output (p=0.035) and CPB peak lactate (p=0.040). Postoperatively we observed significant increased biomarkers level in both groups, with no significant difference between the groups: mean CRP (p=0.115), mean ESR (p=0.214) and cTnI (p=0.363). We observed a significant negative correlation between the mean change in CRP levels and mechanical ventilation (r=- 0.548, p=0.002) in the seropositive group, but not in the uninfected group (r=0.025, p=0.893). The correlation between the difference in CRP and ICU stay was not significant between in both group (r=-0.231, p=0.229 and r=0.25, p=0.975, respectively). A significant positive correlation between postoperative cTnI and the inotropic support duration (r=0.384, p=0.040) was seen in the seropositive groups, but not in the negative group (r=0.092, p=0.622). Furthermore we observed a significant drop in CD4 cells postoperatively (p=<0.001) in the HIV seropositive group. Antiretroviral treatment appeared to influence the degree of change in CD4 cells postoperatively.

Conclusion: We conclude that HIV positive patients’ postoperative reactions to cardiac surgery supported by CPB are similar to those of HIV seronegetive patients. We further report non-paralleling correlations between the biomarkers and perioperative events; however these do not seem to affect the overall outcomes between the two groups.