The coronary arteries are blood vessels that provide oxygen rich blood to the muscle of the heart. If these vessels become narrowed or blocked, this can lead to chest pain (called angina) or heart attacks. Narrowings are usually treated using metal scaffolds called drug eluting stents. However, in one in five cases where the narrowing occurs at a branching point, treating it with stents is more challenging and can cause complications. A possible alternative treatment is using a special type of balloon called a drug-coated balloon. This balloon is inflated in the blood vessel and releases medicine to help widen the blood vessel and the procedure is completed without leaving any metallic scaffold behind.

This study aims to compare drug coated balloons with drug eluting stents to see which treatment works better for narrowing that occurs at branching points. We will used advanced imaging techniques to create computer models of blood flow in the vessels, and we will follow up with patients over tie to see how well the treatments work.

Inclusion Criteria:

• Age 18 or over
• Any bifurcation lesion amenable to a provisional main vessel treatment strategy
• A main vessel diameter of 2.5mm or more and side branch diameter of >2mm
• Any patient with stable angina, silent ischaemia, unstable angina or NSTEMI
• Able to give informed consent

Exclusion Criteria:

• Cardiogenic shock
• LVEF <30%
• STEMI (as unable to give informed consent)
• eGFR <30
• Severe asthma contraindicating use of adenosine
• High degree AV block on 12 lead ECG precluding the use of adenosine
• Pregnancy
• Inability to consent
• Left main stem coronary bifurcation lesions

Any patient with coronary bifurcation lesion who fulfills the inclusion criteria and is not precluded by the exclusion criteria is suitable for recruitment.