Cardioplegic or Fibrillatory Arrest for Correction of Partial and Intermediate Atrioventricular Septal Defects?

Objectives: Certain congenital cardiac surgeries can be performed in
ventricular fibrillation (Vfib) as an alternative to cardioplegic arrest. Use
of Vfib facilitates minimally invasive procedures via partial inferior sternotomy
and avoids cardioplegia related problems, but could involve other risks, e.g.,
air embolism. This study was conducted to compare the two techniques with
regard to myocardial damage, operative results and outcome. 

Methods: A retrospective analysis (2012–2014) was performed. 21
patients with partial or intermediate atrioventricular septal defect (AVSD)
were assigned to either group A: crystalloid cardioplegia (n = 10, mean age: 0.8 ± 1.5 years, range: 0.3–7
years) or group B: ventricular fibrillation (n = 11, mean age: 5.7 ± 5.9 years, range: 0.8–19
years). Patients in group A underwent full sternotomy, while 9/11 (81%)
patients in group B had partial inferior sternotomy. All patients were operated
with extracorporeal circulation (ECC) and mild hypothermia. ASDs were closed by
autologous pericardial patch, VSDs, if present, by direct suture. AV-valves
were reconstructed, at least with closure of the cleft in left AV-valve.High-sensitive
troponin T (hsTNT) and CK-MB were measured on arrival in the ICU and on the 1st
postoperative day. 

Results: Procedure time (A: 200 ± 20
minutes vs. B: 208 ± 44 minutes, p = 0.55) and ECC time (A: 114 ± 13 minutes vs. B: 116 ± 28 minutes, p = 0.82) did not differ. All
patients were successfully weaned from CPB. After arrival in the ICU, hsTNT was
3705 ± 2112 pg/mL in group A and
3142 ± 1947 pg/mL in group B (p = 0.562). On postoperative
day 1, hsTNT was 2100 ± 1421 pg/mL in group A and
1644 ± 739 pg/mL in group B (p = 0.461). CK-MB was 270 ± 113 U/L in group A and 224 ± 106 U/L in group B (p = 0.324) directly after the
procedure. On post-operative day 1, CK-MB was 80 ± 38 U/L
in group A and 104 ± 56 U/L in group B (p = 0.425). No need for
re-operation occurred, no residual ASD/VSD was detected. AV-valves
regurgitation was mild at most if present at all. No deaths or strokes were
observed. 

Conclusion: Use of Vfib did not obstruct weaning from CPB in patients
undergoing partial and intermediate AVSD repair. Vfib did not increase
myocardial damage as determined by postoperative cardiac enzyme release. Use of
Vfib did not increase the risk of cerebrovascular events in the study
population investigated. Therefore, Vfib proved to be a safe alternative to
cardioplegic arrest and facilitated use of partial sternotomy in most patients.