Mortality rates of interventional and surgical procedures performed in domestic juvenile farm pigs and Yucatan mini-pigs

Perioperative and postoperative care are critical factors in cardiac catheterization and cardiothoracic surgical procedures. A retrospective analysis of mortality data in cardiovascular catheter and surgical studies performed in domestic juvenile swine (DJS) and Yucatan mini-swine (YMS) was conducted. A total of 529 animals in 35 studies were included in the analysis, which included six study categories: coronary stenting (Stent) and percutaneous transluminal coronary angioplasty (PTCA) alone; Stent and PTCA in combination with ionizing radiation (Stent/Rad, PTCA/Rad); myocardial ischemia (ISCH); and three non-ISCH surgical procedures grouped under "other surgeries" (Other Surg). Casualties were defined as animals that died spontaneously before the assigned termination date. The highest mortality rate occurred in the ISCH group (29.7% ± 2.2%). Mortality of the Stent/Rad animals (26.1% ± 6.3%) was significantly higher than those in the Stent and PTCA groups (12.1% ± 3.1% and 7.9% ± 3.2%; P < 0.05 for both). Similarly, mortality in the ISCH group was significantly higher than that in the Stent, PTCA, or Other Surg animals (29.7% ± 2.2% versus 12.1% ± 3.1%, 7.9% ± 3.2%, and 3.0% ± 3.0%, respectively; P < 0.05 for all comparisons). We did not observe differences between YMS and DJS. Most casualties in the ISCH group took place during weeks 1 (28.0% ± 8.4%) and 4 (29.3% ± 6.2%) after placement of the coronary ameroid constrictor. The majority of animals in the Stent/Rad and PTCA/Rad groups died within 1 week after the procedure (67.7% ± 12.8% and 79.3% ± 12.5%, respectively). We conclude that radiation therapy used in combination with stenting increases the mortality rate of this catheter-based procedure. Animals subjected to ISCH or a transcatheter procedure in combination with ionizing radiation should be monitored closely during the perioperative period to prevent unacceptably high mortality rates.