3.3 Comparisons between internal and external BiVADs: utilization, mortality, LOS, cost, and complications
Internal BiVADs were implanted in 538 (42.5%) patients and external BiVADs in 727 (57.5%) patients (see Table 3). More patients were female in the external BiVAD group (30.1% vs 18.4%, p = 0.024). There were no significant differences between internal and external BiVADs in insurance coverage, size, and teaching status of the hospitals, as well as elective cases. More of the external BiVAD implantation occurred in the Northeast compared to the internal BiVADs (36.0% vs. 14.9%,p = 0.002). Internal BiVAD implantations were more likely than external BiVAD implantations to take place in urban teaching hospitals (98.3% vs. 90.3%, p < 0.001). Significantly more patients in the external BiVAD group had documented history of CAD (44.9% vs. 22.1%, p < 0.001), pulmonary circulatory disorders (5.3% vs 0, p = 0.014), and valvular disease (7.2% vs. 0, p = 0003). History of renal failure was more prevalent in the internal BiVAD group (36.1% vs. 16.1%, p < 0.001).
Higher mortality was observed among patients with external BiVADs compared to those with internal BiVADs (59.1% vs. 45.4%, p = 0.022, see Table 3). Internal BiVADs were associated with longer median LOS (64.0 vs. 20.0 days, p < 0.001) and higher cost ($468,321 vs. $208,809 per hospitalization, p < 0.001). There were more complications of acute renal failure (85.6% vs. 74.0%, p = 0.020) and hemolytic anemia (4.5% vs. 0.7%,p = 0.038) among those with internal BiVADs. There were no significant differences in rates of bleeding, infection, or stroke.