PHILADELPHIA – Endovascular repair may be better than open surgery for emergency treatment of patients with a thoracic aortic aneurysm rupture who receive care at smaller U.S. hospitals, based on an analysis of more than 900 patients treated during 2006-2008.
Investigators found that emergency thoracic endovascular aneurysm repair (TEVAR) led to a nearly 80% reduction in complications, compared with open surgical aneurysm repair, in patients who were treated at smaller U.S. hospitals. At larger hospitals, TEVAR and open repair produced similar outcomes, Dr. Raja R. Gopaldas said at the annual meeting of the American Association for Thoracic Surgery.
"TEVAR is an ideal alternative when transfer to a larger facility is not feasible," said Dr. Gopaldas, a cardiothoracic surgeon at the University of Missouri in Columbia.
"We were surprised when we saw that smaller hospitals had better outcomes with TEVAR, but it makes sense. A lot of hospitals lack expertise in open thoracic aortic repair because it requires a highly skilled surgeon, whereas a lot of small hospitals have a cardiac catheterization lab and a cardiologist or vascular surgeon available," he said in an interview. He added that open repair was more successful when performed at larger hospitals, but when TEVAR was used, results were similar.
Widespread availability of TEVAR catheter systems began in 2005. During 2006-2008, TEVAR was used in 40% of emergency thoracic aortic aneurysm repairs. Because these were the first 3 years after U.S. approval, such a high level of TEVAR use, especially in emergency circumstances, fell beyond Dr. Gopaldas’s expectations. "Forty percent is a huge number," he said.
The findings also suggested a role for "TEVAR first" in the emergency repair of ruptured thoracic aortic aneurysms, because the operative team often can intervene more quickly with an endovascular approach than with open surgical repair.
"I think there will be a lot of push to use the endovascular approach more frequently, because it is probably a lot quicker to set up your team," Dr. Gopaldas said. ""It’s quicker to get a TEVAR stent deployed than to cut open a patient’s chest. The endovascular team is probably geared to respond more quickly [than is] the open-heart surgical team in smaller hospitals. In bigger hospitals, there may not be as much of a difference."
The study used data collected by the Nationwide Inpatient Sample, an annual sampling of slightly more than 1,000 U.S. hospitals – about 20% of all U.S. patient discharge records – done by the Agency for Healthcare Research and Quality. Using data for 2006-2008, Dr. Gopaldas and his associates identified 923 patients who underwent emergency repair of a thoracic aortic aneurysm at one of 107 hospitals that performed these repairs. Among those hospitals, 41 (38%) performed TEVAR.
The analysis also divided hospitals into smaller and larger hospitals based on bed numbers. The definition of "smaller" differed based on U.S. geographical region (Northeast, Midwest, South, or West), rural vs. urban, and teaching vs. nonteaching hospitals. The bed sizes of smaller hospitals ranged from 1 to 449 (an urban teaching hospital in the Southern region). Larger hospitals included any center with a bed number larger than the study definition of smaller. Among the 107 hospitals that performed TEVAR during the study period, 27 (25%) were smaller hospitals.
In a risk-adjusted analysis, patients who underwent open surgical repair at a smaller hospital had a threefold increased risk for a subsequent complication, compared with patients treated by surgery at a larger hospital. But among the patients treated with TEVAR, the outcomes at smaller hospitals matched those that were achieved at larger hospitals. A comparison of open surgery and TEVAR outcomes within smaller hospitals showed that TEVAR led to a 79% lower complication rate, Dr. Gopaldas reported. In larger hospitals, outcomes were similar for patients treated with open surgery vs. TEVAR.
The risk-adjusted analysis also showed that once patients developed complications, they fared worse in smaller hospitals regardless of the type of aneurysm repair they received. Smaller hospitals had a failure-to-rescue rate that was nearly fourfold higher than that of larger hospitals. By lowering complication rates, TEVAR proved especially advantageous in smaller hospitals, Dr. Gopaldas said. He did these analyses in collaboration with researchers from Baylor College of Medicine and the Texas Heart Institute, also in Houston.
Dr. Gopaldas said that he had no relevant financial disclosures.