Large Thoracic Aortic Aneurysm Research Supports Recommendations

The majority of the 33,000 Americans who are diagnosed with a thoracic aortic aneurysm each year—a bulge in the section of the main artery that runs through the chest—are not likely to experience an aortic dissection and may not require open-heart surgery, according to a sizable, recent Kaiser Permanente study.

According to the primary author, Matthew D. Solomon, MD, Ph.D., a cardiologist at Kaiser Permanente and a physician researcher at the Kaiser Permanente Division of Research, “we constructed the largest-ever cohort of patients with thoracic aortic aneurysm to analyse their natural history.”

This study was essential due to the paucity of information to help clinicians and the ongoing controversy over the size of an aneurysm before recommending a patient undertake a very risky procedure.

The greatest study to date supporting the current consensus guidelines that advise surgery for the majority of patients with a thoracic aneurysm that is 5.5 cm or greater was published on October 5 in JAMA Cardiology. These recommendations are only applicable to persons who do not suffer from particular hereditary disorders that raise their chance of developing an aortic aneurysm or dissection.

6,372 Kaiser Permanente patients from Northern California who were diagnosed with a thoracic aortic aneurysm between 2000 and 2016 were included in the study. Of them, 6 092 (96%) had aneurysms that were first diagnosed to be smaller than 5.5 centimetres, and 280 (4%) had aneurysms that were initially assessed to be larger than 5.5 centimetres.

To guarantee that each patient received the proper, continuing imaging needed to gauge the size and progression of their aneurysm, all patients were enrolled in a computerised population management system. None of them had a hereditary condition that raises the chance of developing an aortic aneurysm or dissection.

Less than 1% of patients with aneurysms smaller than 5.0 centimetres and 1.5% of individuals with aneurysms 5.0 to 5.4 centimetres had a 5-year risk of an aortic dissection.

But for patients with aneurysms 5.5 centimetres or larger, the situation was different: the estimated probability of a dissection over the next five years was 3.6% for aneurysms 5.5 to 5.9 centimetres, and it increased to more than 10% for patients with aneurysms 6 centimetres or larger.

Dr. Solomon, the founder and director of the Kaiser Permanente Center for Thoracic Aortic Disease, stated that the study “shows that regular monitoring, combined with aggressive blood pressure control and lifestyle changes, is a safe strategy for most patients up until the aneurysm reaches the 5.5 centimetres mark, when surgery becomes necessary.”

The discovery of a distinct risk inflection point at 6.0 cm “supports the present guidelines and will assist inform the discussion of when to perform surgery,” according to the study.

The largest blood conduit in the body, the aorta, has a diameter similar to that of a garden hose. From the heart, it transports blood to all of the essential organs. A thoracic aortic aneurysm normally has no symptoms and is only unintentionally found during a scan for another illness.

Aneurysm repair can be done surgically to stop dissection by skilled heart surgeons. The heart may need to be stopped during the complicated treatment, and patients may need to be placed on a heart-lung bypass machine to take over the heart’s pumping duties. The procedure necessitates a hospital stay of up to 10 days, a recovery period of two to three weeks, and can put patients at risk for a heart attack, stroke, pneumonia, and loss of renal function.

It can be one of the most challenging surgeries that our excellent cardiac surgeons and great aortic surgery programme perform, according to Dr. Solomon.

“When the risk of the procedure is less than the risk of dissection, patients certainly require it. When deciding whether to undergo such a substantial treatment, our study will assist doctors and patients in making the best decision possible.”

A multispecialty team of cardiologists, cardiac surgeons, vascular surgeons, cardiovascular geneticists, and imaging analysts make up the Kaiser Permanente Center for Thoracic Aortic Disease, which opened its doors in 2017. Through its innovative population management programme, the team provides care for approximately 15,000 Kaiser Permanente patients in Northern California. It has presented its work and exchanged best practises both nationally and globally.

According to senior author Alan S. Go, MD, a senior research scientist at the Division of Research, “This type of study in a very large, diverse population where patient characteristics, care received, and outcomes experienced are systematically captured across all practise settings is only possible within fully integrated health care delivery organisations like Kaiser Permanente.”

To enable accurate risk prediction and optimise therapeutic choices for thoracic aortic aneurysms, it is imperative to conduct these long-term follow-up studies among representative patients.