SamDawkinsConsultant Cardiologist

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 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.

TAVI or open-heart surgery?How the choice of aortic valve treatment is made

Two ways to replace the aortic valve

A narrowed aortic valve can be replaced in two ways: with TAVI, through the artery at the top of the leg, or with surgical aortic valve replacement, an open-heart operation. Both are well established. The choice is made together with you, after discussion at a meeting of cardiologists, cardiac surgeons, imaging specialists and anaesthetists.

What do the guidelines say?

The 2025 European guidelines recommend [1]:

  • TAVI for people aged 70 or over with a normal three-leaflet aortic valve, if the anatomy is suitable.
  • TAVI for people aged 75 or over, at high risk from surgery, or unable to have surgery.
  • Surgery for people under 70 at low risk from surgery.
  • Either, for everyone else, depending on their heart and general health.

For a bicuspid valve, which has two leaflets instead of three, the guidelines are more cautious. TAVI may be considered for people at increased risk from surgery, if the anatomy is suitable [1].

What can favour surgery?

  • Another heart problem that needs an operation at the same time: for example, another valve that needs treating, complex narrowings of the coronary arteries that need bypass surgery, or an enlarged aorta.
  • Valve anatomy that suits surgery better: for example, a bicuspid valve, very heavy calcium at the base of the valve, a valve outside the range of TAVI sizes, or a risk of blocking the arteries that supply the heart muscle.

What can favour TAVI?

  • Suitable arteries in the legs, so the valve can be delivered through the groin.
  • Things that make an operation riskier: for example, frailty, other medical conditions, previous bypass surgery with grafts that are still working, a heavily calcified aorta, previous radiotherapy to the chest, or a severe chest deformity or curvature of the spine.

What is recovery like?

  • TAVI: most patients go home the same day or after one or two nights. There is no wound on the chest, and many people notice an improvement in their breathing straight away or over the following weeks.
  • Surgery: the operation is usually carried out through the breastbone, which needs time to heal, so the stay in hospital and the recovery afterwards are longer. Most patients stay in hospital for between five and seven days. Some patients may be suitable for minimally invasive aortic valve replacement, where the surgeon uses a smaller incision, either through the upper part of the breastbone or between the ribs on the right side of the chest, which leaves a smaller scar. Whether this is possible depends on your anatomy, and is decided with the cardiac surgeon.

The PARTNER 3 trial compared TAVI with surgery in 1,000 patients at low risk from surgery, with an average age of 73 [2]:

  • Hospital stay: the typical stay was 3 days after TAVI and 7 days after surgery (P<0.001).
  • Symptoms and walking distance: these improved sooner after TAVI. By one year, the difference between the two groups had narrowed.
  • Irregular heart rhythm: new atrial fibrillation developed in the first month in 5.0% of TAVI patients, compared with 39.5% after surgery (P<0.001).

Thinking ahead

Tissue valves, whether surgical or TAVI, can wear out over time, so younger patients may need another procedure later in life. The guidelines ask the heart team to plan the first procedure with this in mind [1]. A worn surgical valve can often be treated with a TAVI valve placed inside it, and a worn TAVI valve with a second TAVI, but each of these has its own risks, and removing a TAVI valve surgically carries more risk than a first operation. Dr Dawkins will talk through how this applies to you.

References

  1. Praz F, et al. 2025 ESC/EACTS Guidelines for the management of valvular heart disease. European Heart Journal 2025;46:4635–4736. doi:10.1093/eurheartj/ehaf194
  2. Mack MJ, et al. Transcatheter aortic-valve replacement with a balloon-expandable valve in low-risk patients. New England Journal of Medicine 2019;380:1695–1705. doi:10.1056/NEJMoa1814052