Extended Statement by the British Cardiovascular Intervention Society President Regarding Transcatheter Aortic Valve Implantation.

Service Specification for TAVI: Recommendations of the British Cardiovascular Intervention Society – Updated July 2019 Severe AS (sAS) is the most common primary valve disease leading to surgery or catheter intervention in Europe and North America, with a growing prevalence due to the ageing population.[3] It is a degenerative condition in which the outflow of blood from the heart is restricted by progressive narrowing of the aortic valve. This leads to symptoms of breathlessness, exertional chest pain or blackouts. Untreated, the condition causes left ventricular failure and death, with up to 40% of patients dying within 1 year of symptom onset. No medical therapy can improve outcome for this condition and therefore valve intervention is the only treatment option that alters prognosis. The standard of care for this condition has historically been surgical aortic valve replacement (sAVR), but around one-third of patients are ineligible for sAVR due to a combination of age and comorbidities. TAVI is a transformational technology; it is a much less invasive approach than sAVR and involves implantation of a new valve without the need for complex surgery or the use of a heart–lung bypass machine. This is most commonly done via the femoral arteries (transfemoral or TF approach), but it may also be accomplished via the subclavian arteries or via minimally invasive access using the cardiac apex between the ribs, directly into the aorta through a small incision. Less common approaches via the carotid arteries, axillary artery and the femoral veins or abdominal aorta have also been described. Therefore, for most patients undergoing TAVI, the procedure is performed via the femoral artery, under local anaesthesia or conscious sedation in a catheter laboratory. This results in quicker patient recovery, a shorter hospital stay and reduced use of expensive and limited resources such as cardiac operating theatres and intensive care unit beds, as well as postoperative nursing care. A number of different valve designs are available, including balloon-expandable and self-expandable devices. Each has different performance characteristics, which may be tailored to specific anatomical or patient-specific features. TAVI has been proven to be superior to medical therapy for inoperable patients and superior to sAVR in patients who are high risk for sAVR (Society of Thoracic Surgeons [STS] or Euroscore II >8%).[4–6] Trials have also shown that patients with intermediate surgical risk (STS or Euroscore II >4%) who are eligible for a TF approach have superior outcomes with TAVI.[7–9] Moreover, randomised trials have shown TAVI to be superior to sAVR in patients classified as low risk (STS <4), with outcome data so far published to 12 months.[10,11]