Trans-coronary Pacing to Assess Myocardial Viability

Narrowing of the coronary arteries can cause chest pain and weaken the heart. In patients who have had heart attacks, blocked or severely narrowed arteries should be investigated (with coronary artery x-rays, or angiography) with efforts undertaken to improve the blood flow (angioplasty and stenting or heart bypass surgery). Sometimes these arteries are in fact supplying heart tissue which is already dead. Procedures to open up these vessels will therefore not influence how the patient feels or their future prognosis. On occasion, in order to determine whether heart tissue is alive (viable) and likely to benefit from of such efforts, a further investigation is required before another attempt is undertaken to open up these diseased arteries. This will require imaging of the heart to assess the state of the tissue (for example with magnetic resonance imaging, or cardiac MRI which is the gold standard). This means that patients may require two invasive procedures. One way around this would be to assess the electrical properties of the heart muscle in question during a single procedure. The principle is simply that dead muscle will have no electrical activity. Assessing the electrical properties of the heart through the coronary arteries using the same equipment used to treat the diseased artery during initial coronary angiography may provide viability information instantly, thus allowing treatment to proceed at the same procedure. In order to investigate whether this approach has promise, we will be performing a cardiac MRI around the time that patients have their coronary angioplasty. The electrical data will be compared to the cardiac MRI results to determine if this technique can be used in clinical practice. This innovative work has potential clinical and financial benefits.

Furthermore, patients can be diagnosed and treated during one procedure