Managing aortic aneurysms in primary care
Ruptured aneurysms can be one of the most fatal medical emergencies and are dubbed as a “silent killer” given their lack of symptoms. Audrey Abella speaks with Dr Julian Wong Chi Leung, Senior Consultant at the Department of Cardiac, Thoracic and Vascular Surgery at the National University Heart Centre, Singapore, on how this potentially life-threatening condition can be aptly diagnosed and prevented in the primary care setting.
Globally, males have a higher prevalence of aortic aneurysms, with a male-female ratio of 6:1. About 2 percent of males over 60 years are predicted to have an aortic aneurysm.
Aortic aneurysms are curable; however, most aneurysms remain unknown until they rupture. This then becomes an emergency with a very high morbidity and mortality rate, thus requiring immediate surgical intervention. If immediate attention is given, the mortality rate may be <2 percent; however, in an emergency setting, the mortality rate can be as high as 50 percent. If treated successfully, patients may return to their normal conditions with proper therapy, maintenance, and monitoring.
While the exact pathophysiology remains unknown, the risk of having aortic aneurysms particularly increases among individuals with a high blood pressure (BP) and those who smoke. When the size of the aorta increases to 3 cm, which exceeds the normal aorta size of 1.5–2 cm, it could indicate the presence of an aneurysm. Growth rate is about 10 percent per year, and most ruptures occur beyond 5 cm.
Diagnosing aortic aneurysms
There are two types of aortic aneurysms – thoracic and abdominal. A thoracic aneurysm refers to a weakened area in the upper part of the aorta, the major blood vessel running from the heart through the center of the chest and abdomen which supplies blood to the body. An abdominal aneurysm refers to an enlarged area in the lower part of the aorta, within the abdominal cavity.
Aortic aneurysms often occur deep inside the abdomen, rendering diagnosis difficult. Another difficulty is convincing asymptomatic patients to undergo screening exams. When patients present with abdominal pain, it could be a late indication of an impending aneurysm rupture that already requires immediate surgical intervention.
Therefore, GPs should be able to distinguish clues that signify the presence of an aneurysm to facilitate an early and accurate diagnosis and referral to a cardiovascular specialist. A diagnosis of peripheral vascular disease among patients over 60 years warrants a full clinical examination to determine the presence of, or rule out, an aortic aneurysm.
However, clinical examination and medical history may not be sufficient to confirm the diagnosis of aortic aneurysm. An ultrasound or a CT scan may aid the detection of an aortic aneurysm.
It is thus important to establish a national screening programme to facilitate proper diagnosis of aortic aneurysm. High-risk patients with a history of cardiac disease, hypertension, and smoking are encouraged to participate in screening programmes to establish any potential signs of aneurysm.
Primary care providers may refer to the US and UK clinical guidelines, as well as the NICE, SVS, and ESVS guidelines*, for proper management of aortic aneurysms. These guidelines are straightforward; however, diagnosing the disease is quite challenging due to the lack of obvious symptoms.
Treating aortic aneurysms
At the primary care level, treatment must be directed towards optimizing medical therapy. When a diagnosis of aneurysm is established, GPs should focus on optimizing BP by administering antiplatelets (ie, aspirin, clopidogrel) and/or statins (ie, simvastatin, atorvastatin) to reduce aneurysm. Referral to a cardiovascular specialist centre should follow for proper surgical management (ie, open heart surgery, or minimally invasive endovascular stenting) and monitoring.
Given the lack of symptoms, GPs are mostly faced with the struggle of convincing their patients to comply with regular medicine intake and BP monitoring. Therefore, it is critical for GPs to collaborate with cardiovascular specialists when dealing with potential aneurysm cases. GPs can help in BP monitoring and control; cardiovascular specialists may take charge when surgical intervention is warranted.
Surgical intervention is not usually warranted until the aneurysm reaches 5.5 cm. Smaller aneurysms may be monitored through annual ultrasound. This can be facilitated by establishing links between cardiovascular specialist centres and polyclinics to offer primary care patients a direct access to ultrasound whenever necessary.
Detecting aneurysms could be difficult, but it is essential especially in a high-risk population. Small aneurysms should be monitored, and patients should strictly adhere to the necessary medications upon diagnosis. High-risk patients need to be referred to cardiovascular specialist centres to establish a diagnosis and to employ surgical intervention when necessary.