**5. Pulmonary endarterectomy – Introducing a new technology into the NHS**

Chronic thromboembolic pulmonary hypertension (CTEPH) is a form of pulmonary hypertension that occurs as a result of chronic pulmonary embolic blood clots occluding the arteries to the lungs. Over time these emboli build up in the pulmonary arteries causing occlusion and scarring with narrowing of the vessels which eventually leads to reduced blood flow, pulmonary arterial hypertension and right sided heart failure.

Pulmonary endarterectomy (PEA, and previously known as PTE or pulmonary thromboendarterectomy) is a complex cardiac surgical procedure used to remove the blood clots and scarred elements of the vessel walls and restore blood flow through the lungs. It is used as a surgical treatment of CTEPH in those patients where this is appropriate (not all patients with CTEPH are surgical candidates).

This is technically difficult surgery which was introduced into the NHS in 2000 (through national commissioning) at a single centre in the UK at Papworth Hospital NHS Foundation Trust. This allowed the necessary expertise to be developed and outcomes were monitored using the established monitoring and reporting mechanisms established for adult heart and lung transplantation, and with which Papworth Hospital NHS Foundation Trust were already contributing to as an adult cardiothoracic transplant centre.

The concentration of expertise in this single centre aligned to real-time monitoring of mortality outcomes for all patients undergoing PEA has resulted in the outcome data (30 day mortality) at Papworth Hospital NHS Foundation Trust now being consistent with the best in the world.

The effectiveness of this approach will also be highlighted using the example of setting up routine systems for monitoring early mortality in pulmonary endarterectomy to monitor introduction of a new surgical technique into the UK in a single centre. The benefit of experience and systems that allow the development of expertise are shown in the learning curve attached to introducing this technique. Data are emerging that show that the international results are strongly linked to volume.
