Aortic Stenosis
Aortic stenosis is a narrowing of the aortic valve, the valve between the left ventricle and the aorta (the main artery leaving the heart). It is one of the most common heart valve abnormalities. In the early stages, it requires no treatment, just monitoring with serial heart scans. Aortic stenosis is graded as mild, moderate or severe. Once the disease becomes severe, monitoring becomes more frequent — and as soon as symptoms develop or heart function shows any sign of deterioration, treatment should be considered.
What are the symptoms of aortic stenosis?
Aortic stenosis can be asymptomatic. More commonly, as the stenosis becomes severe, patients develop shortness of breath on exertion. More advanced symptoms include breathlessness on minimal exertion, chest pain, dizziness and blackouts.
How is aortic stenosis assessed?
Most patients with aortic stenosis are first identified by a heart murmur picked up with a stethoscope. The investigations build a picture of how narrow the valve is, how the heart is coping, and whether intervention is appropriate.
- Electrocardiogram (ECG) — looks for left ventricular hypertrophy (a thickened pumping chamber working against the narrowed valve) and arrhythmias such as atrial fibrillation.
- Transthoracic echocardiogram (TTE) — the principal test. Visualises the valve directly, measures the gradient and valve area, and assesses heart function. AS is graded mild, moderate or severe.
- Transoesophageal echocardiogram (TOE) — higher-resolution images, usually performed when intervention is being planned.
- Stress echocardiography — used in selected patients, particularly those with severe AS but no clear symptoms (to bring out exertional changes), or those with reduced ventricular function (to confirm the severity).
- Cardiac MRI — measures fibrosis in the heart muscle, which can influence the timing of intervention; increasingly used in borderline cases.
- Cardiac CT — essential before TAVI for accurate sizing of the new valve, assessment of vascular access, and a calcium score of the aortic valve.
- Coronary angiography — an invasive look at the coronary arteries, generally performed before any valve intervention to check for coexisting coronary disease.
- Blood tests — kidney and liver function, BNP (a marker of heart strain), full blood count.
How is aortic stenosis treated?
Medication can help symptoms but does not change the progression of the disease. The only definitive treatment is to replace the aortic valve, either with surgical aortic valve replacement (SAVR) or with transcatheter aortic valve implantation (TAVI).
What experience does Dr Dawkins have in the management of aortic stenosis?
Dr Dawkins sees and treats hundreds of patients with aortic stenosis every year. He is a high-volume TAVI operator and runs the TAVI multidisciplinary meeting in Oxford, where every new symptomatic severe aortic stenosis referral is reviewed by interventional cardiologists, surgeons, imaging specialists and anaesthetists.