Nationwide Analysis of Interfacility Transfers for Acute Type A Dissection

Purpose: Interfacility transfer (IT) of patients presenting with acute type A dissection (ATAAD) may allow for definitive care. It is unknown how common this practice is and whether operative mortality or readmission rates are affected. We evaluated national trends and outcomes in open ATAAD repair following IT in the United States.

Methods: Adults undergoing open repair for acute type A dissection were identified using the 2016 to 2019 Nationwide Readmissions Databases, an all payor dataset. Cases were identified by diagnostic and procedural codes. Analysis was performed with adherence to the health care cost and utilization project analysis (HCUP) guidelines. Interfacility transfer was defined as a patient who was discharged from a facility and readmitted to another facility in the same day, or if a transfer record was present. Primary endpoints included in-hospital mortality and 30-day readmission. Secondary outcomes included 90-day readmission, length of stay and inpatient costs. Propensity score matching was performed to balance patients who underwent IT compared to those who did not.

Results: A total of 10,434 individuals (65% male), representing a national estimate of 18,900 cases, underwent open surgical repair for ATAAD with 1,421 (14%) transferred from another facility. Patients who underwent IT were more likely to come from urban non-teaching (10% vs. 9%, p< 0.05) and rural hospitals (11% vs. 8%, p< 0.05) vs. academic teaching facilities. These patients had greater Elixhauser comorbidity burden (7 vs 5, p< 0.001) including renal disease (31% vs. 25%, p< 0.001), pre-existing heart failure (39% vs. 27%, p< 0.001), pulmonary disease (31% vs. 24%, p< 0.001), diabetes (22% vs. 15%, p< 0.001), and hypertension (91% vs. 83%, p< 0.001). Patients undergoing IT were less likely to die during their index admission (10% vs. 15%, p< 0.001), but had higher costs ($130,000 vs. $83,000, p< 0.001) and hospital length of stay (22 vs 11 days, p< 0.001). Propensity score matching suggested a statistically significant greater difference in in-hospital mortality between transferred vs. non-transferred patients (10% vs. 18%, p< 0.001) as well as lower rates of all-cause readmissions at 30- (20% vs 26%, p=0.006) and 90-days (31% vs 37%, p< 0.001).

Conclusion: National rates of interfacility transfer suggest that adoption of transfer for ATAAD is low. Patients undergoing successful IT for ATAAD are highly comorbid, but have improved early outcomes compared to those who are not on both matched and unadjusted analysis. These findings support literature in favor of IT to high volume aortic centers.

Identify the source of the funding for this research project: None