Abstract 2751: Preoperative Cardiothoracic Computed Tomographic Angiography is Associated with Increased Adoption of Preventive Surgical Techniques in Patients Undergoing Redo Open Heart Surgery after Prior Coronary Artery Bypass Grafting
Introduction: Redo cardiothoracic surgery (CTS) is associated with increased morbidity and mortality, compared to first-time CTS. Multi-detector computed tomography angiography (MDCTA) reliably delineates the course of previous coronary artery bypass grafts (CABG) and proximity of mediastinal structures to chest wall. We sought to determine if high risk preoperative MDCTA findings impacted use of preventive surgical strategies in patients with prior CABG undergoing re-CTS.
Methods: We studied 167 patients (mean age 69 ± 9 years, 79% men) with prior CABG referred for re-CTS who underwent contrast-enhanced MDCTA (16 – 64 MDCT, 2 mm slice thickness) to assess CABG location and relationship of aorta/right ventricle (RV) to chest wall. Demographic, laboratory, and clinical data were used to determine the Higgins preoperative risk score. Prevalence of high risk MDCTA findings, use of preventive surgical strategies, frequency of severe intraoperative bleeding and postoperative mortality were recorded.
Results: Mean preoperative risk score was high (7.5 ± 3) and 49% patients underwent combined redo CABG plus valve surgery. Incidences of 2nd, 3rd and 4th operations were 78%, 19% and 3%, respectively. High-risk CT findings were as follows: adherence/ proximity (≤ 1 cm) of RV/aorta to chest wall (24%) or bypass graft crossing midline (≤ 1 cm antero-posteriorly) (38%). Preventive surgical strategies included: surgery cancelled (4%), non-midline incision (8%), deep hypothermic circulatory arrest (5%), initiation of peripheral cardiopulmonary bypass (11%), and extrathoracic vascular exposure prior to incision (53%). These surgical strategies were used at a significantly higher frequency in patients with high risk MDCTA findings compared to those without (88% vs. 28%, p<0.0001). After adjustment for multiple clinical variables, only high risk MDCTA finding was significantly associated with operative changes (OR=16 [95% CI 7–36], p<0.001). Frequency of severe bleeding, graft injuries, and 1 month mortality were 3%, 5% and 3 %, respectively.
Conclusions: In high risk re-CTS patients with prior CABG, use of preoperative MDCTA plays a significant role in planning and performance. Impact of preoperative MDCTA on outcomes requires further evaluation.