Roughly 90 percent of patients who survive emergency surgery and hospitalization for Type A aortic dissection will survive at least three years, and patients without pre-existing cardiovascular problems are even more likely to survive, according to an article in a supplement to the July 4 issue of Circulation. The study, which was performed by an international team, involved data from patients. who were treated in the late 1990s and early 2000s for Type A dissection.

“Clearly, this is one of those diseases where if you catch it early you can save lives in the hospital, and with successful surgery your outlook after discharge can look quite good,” said lead author Thomas Tsai, MD, a cardiovascular research fellow at the University of Michigan Medical School. “Of course, those who do survive will have a diagnosis for life of aortic disease, and will need medication and aggressive monitoring of their aorta.”

Tsai and senior author Kim Eagle, MD, conducted the research with colleagues from the International Registry of Aortic Dissection, or IRAD, using data on patients treated at 21 medical centers in 11 countries.

“Aortic dissection is still very much a lethal health crisis, with mortality approaching 2 percent per hour. But these results show we’re doing a pretty good job in helping patients after they weather the storm of diagnosis and surgery,” said Eagle.

The new study drew its patients from a group of 885 Type A aortic dissection patients who came or were transferred to participating centers. Nearly 30 percent of patients died in the hospital, but long-term follow-up data were available on many of the 617 who left the hospital after surgical or non-surgical treatment. The patients included in the final analysis were treated at eight centers that had compiled long-term follow-up data on most of their patients.

Roughly 90 percent of the 303 patients in the study had surgery; the rest received medical treatment because of advanced age, pre-existing conditions that made surgery too risky, or patients’ refusal to have surgery. Death rates were much higher among the non-surgical patients.

The average age of all patients was 59 years, but a quarter of patients were over age 70 years ? reflecting the fact that aortic dissection can strike relatively young patients with genetic diseases such as Marfan syndrome.

Almost three quarters (72 percent) of patients in the study had hypertension before their dissection. Nearly 25 percent had atherosclerosis, and just under 13 percent had had some sort of prior cardiovascular surgery.

These underlying problems appear to have had a big impact on patients’ risk of dying after leaving the hospital. In fact, patients who had atherosclerosis or previous cardiovascular surgery had twice the risk of dying in the three-year follow-up period as patients without these characteristics. “What predicts an aortic dissection patient’s death after hospitalization are the risk factors they came in with,” said Tsai.

Tsai and Eagle noted that the good news of the new result may have a lot to do with recent advances in emergency diagnosis, surgical and anesthesiology techniques, and intensive-care practices, as well as better post-hospital care of patients using drugs and regular medical imaging. Because IRAD has collected data on so many patients treated within a seven-year period, the study probably better reflects modern treatment of the condition compared with other studies that compiled data from patients treated over several decades.

The consortium of researchers are currently developing tests that would examine DNA or blood to screen high-risk people or the relatives of dissection patients, to make a rapid diagnosis in the emergency room, or to add to long-term monitoring of survivors. Better screening for aneurysms in the aorta, which are involved in a large percentage of dissections, could also help nip more dissections in very early stages.