Marc Peter Bonaca, MD, MPH
Acute aortic syndromes are a problem where the aorta, which is the main blood vessel leading from the heart and supply blood to the rest of the body, is acutely disrupted. There's either a tear, which we call a dissection, there may be bleeding in the wall, which we call hematoma, or there may be an ulceration. All of these are along the same spectrum of disease where there's acute disruption.
Acute aortic syndromes need to be diagnosed rapidly and treated rapidly because they're associated with upfront mortality and morbidity. You have to diagnose the problem quickly and intervene in order to give the patient the best chance of surviving. There are statistics that say that there is about a one percent mortality for every hour or so after the onset of an acute aortic dissection. In fact, when you look at the data, about half of patients that have an acute type A dissection, that's the top part of the aorta, about half of them die before they reach the hospital. And those that reach the hospital, about another half die before they get to discharge. And so the morbidity, or the danger part, of this dissection happens very early, in the order of minutes to hours and that's why every minute counts in terms of diagnosis and treatment.
Aortic dissections, or acute aortic syndromes, tend to happen in two groups of people. Most tend to be older people with risk factors like high blood pressure. But there are patients that come at a younger age and they may have a genetic predisposition such as a connective tissue disorder or another condition that puts them at risk for this. Some of those patients have heritable conditions that can be passed on to family members, or that they’ve inherited from a family member.
It’s important when you meet a patient to understand whether this is something that they’ve acquired just with age and with risk factors or is this something where they had a predisposition that was inherited. Once that initial assessment is done, there are other things that can be done such as genetic testing or blood tests that can help us to identify family members that are at risk.
At Brigham and Women’s Hospital we developed an Acute Aortic Syndrome Program, and we did it recognizing that the optimal treatment of patients that have acute aortic syndromes requires multiple specialists to come together in a coordinated way, very rapidly. Without a system in place, there is a risk of delays that might lead to adverse patient events.
The Acute Aortic Syndrome Program involves people across multiple specialties. This includes Cardiac Surgery, Vascular Surgery, Cardiology and Vascular Medicine, Vascular Imaging, Emergency Medicine and Anesthesia. All of these specialties are critical to determine the optimal care for our patients.
When we formed the Acute Aortic Syndrome program, we recognized that getting all of the key people in the same place right away when the patient arrives is critical to improve outcomes. And so what we did is we developed a pager. When it’s activated, either when the patient is first diagnosed or when a patient’s transferred from the outside, when we know that they're coming, we actually activate it before the patient arrives. And then we get all of those people within minutes into the same place, into the emergency room. They review imaging together, they see the patient and determine the best treatment.
We're able to accomplish that in the order of minutes instead of hours, which we believe will improve outcomes.
Patients either come in through the emergency room because they’ve experienced symptoms, or they're transferred from another hospital. When they arrive, they are greeted by a multidisciplinary team that evaluate all of the information, evaluate them, and determine what the optimal treatment is. They either go to the operating room or to our intensive care unit; and after the operating room or the intensive care unit, to our step down service, all of the time with a multidisciplinary service following them.
One of the critical transitions in care is leaving the hospital and going to the clinic. And again, there the patient is followed by a multidisciplinary team coordinated with their imaging requirements. The patients that have come here with acute aortic dissection in general have done very well. The patients who come in with the most dangerous kind of dissection, what we call a type A dissection, which is the top of the aorta, the mortality rates are low, much lower than what the national average is. And for other types of dissection, it’s even lower. And so overall, the outcomes have been good.
When a patient arrives with acute aortic dissection, of course the acute treatment is critical. But sometimes people don’t understand how critical it is to have continuity of care and long-term follow-up. Most patients that have a dissection need close follow-up and about 30 percent or more will need a repeat procedure or develop some other issue in the future. So it’s critical, particularly those that have endovascular therapy or those that have remaining aneurysms, other problems that they are seen every six months. We have an imaging protocol set up that we watch very carefully so we know if a problem develops and we can intervene before it becomes a problem.
By seeing people regularly in a multidisciplinary clinic and by having a very systematic follow-up imaging so that we do it at set intervals, we're able to determine if complications are developing. So if a patient starts to develop an aneurysm because they have a weakened aorta from this tear that they suffered, we can detect that early, we can notice whether it’s growing, whether there are changes, and we can be thoughtful about how and when to intervene so it doesn’t become an emergency down the road, or worse. And so by having this set follow-up program, we insure that patients are cared for in an optimal way. And through this integrated program, patients come back for one visit. They see all the doctors they need to see and they get their imaging, ideally, on the same day, so it’s one visit to see multiple specialists.