Epicardial placement of human placental membrane allografts in coronary artery bypass graft surgery is associated with reduced postoperative atrial fibrillation: a pilot study for a future multi-center randomized controlled trial

Abstract

Background: Post-operative atrial fibrillation (POAF) occurs in up to 40% of patients following coronary artery bypass grafting (CABG) and is associated with a higher risk of stroke and mortality. This study investigates how POAF may be mitigated by epicardial placement of aseptically processed human placental membrane allografts (HPMAs) before pericardial closure in CABG surgery. This study was conducted as a pilot feasibility study to collect preliminary for a forthcoming multi-center randomized controlled trial.

Methods: This retrospective observational study of patients undergoing CABG surgery excluded patients with pre-operative heart failure, chronic kidney disease, or a history of atrial fibrillation. The "treatment" group (n = 24) had three HPMAs placed epicardially following cardiopulmonary bypass decannulation but before partial pericardial approximation and chest closure. The only difference in clinical protocol for the control group (n = 54) was that they did not receive HPMA.

Results: HPMA-treated patients saw a significant, greater than four-fold reduction in POAF incidence compared to controls (35.2-8.3%, p = 0.0136). Univariate analysis demonstrated that HPMA treatment was associated with an 83% reduction in POAF (OR = 0.17, p = 0.0248). Multivariable analysis yielded similar results (OR = 0.07, p = 0.0156) after controlling for other covariates. Overall length of stay (LOS) between groups was similar, but ICU LOS trended lower with HPMA treatment (p = 0.0677). Post-operative inotrope and vasopressor requirements were similar among groups. There was no new-onset post-operative heart failure, stroke, or death reported up to thirty days in either group.

Conclusions: Epicardial HPMA placement can be a simple intervention at the end of CABG surgery that may provide a new approach to reduce post-operative atrial fibrillation by modulating local inflammation, possibly reducing ICU and hospital stay, and ultimately improving patient outcomes.

Keywords: Aseptically processed human placental membrane allograft.; Coronary artery bypass grafting; Post-operative atrial fibrillation.

Fig. 1

The HPMAs used were comprised of both placenta-derived amnion and chorion, superior to amnion-only membranes, by improving handling properties due to a thicker tissue bilayer, as well as an increased amount of naturally preserved placental factors

Fig. 2

Placement of 3 HPMAs (5 × 6 cm) prior to pericardial approximation and closure

Fig. 3

Comparison of key pre-operative risk factors for AFib (age, BMI, and history of MI) between control and treatment groups. Full comparison of characteristics is given in Table 1

Fig. 4

Comparison of operative parameters (number of vessels bypassed, total cardiopulmonary bypass, and aortic cross-clamp time) between control and treatment groups

Fig. 5

Significant decrease (p = 0.0136) in new onset POAF with HPMA treatment from 35.2 to 8.3%

Fig. 6

Comparison of hospital and ICU length of stay by group. No significant difference between groups, but ICU LOS trended shorter in the treatment group