Hi shambles,
Trying to diagnose you no less provide advice is extremely difficult. Others on this site mean well, but your problem is a complex one. First of all, you obviously have significant coronary artery disease. One would need to know which artery was involved in the 2005 and 2006 episodes. The reason for being unable to stent you is crucial. The long term use of anticoagulants for coronary artery disease is fraught with complications and uncertainty regarding the indications. Thus, it is not possible to assume that you will or will not be on long term Coumadin therapy. This therefore should not influence your choice of valves. The factors that you should consider relate to your primary coronary artery disease and your age. The duration of competence of porcine valves is between 12-15 years. If your life expectancy is greater than that, you might consider a mechanical valve. However, the stroke risk from a mechanical valve exceeds that of a porcine valve.
Let me make some assumptions. You are a 65 year old male with significant coronary artery disease such that your life expectancy is between 8-12 years. You are today not a class I anesthesia or surgical risk. If you should be lucky enough to outlive the life expectancy of a porcine valve then you would face open heart surgery at about the age of 77-82. Your risks from surgery would be even greater then compared to today.
To get to your original question and the ?bridging? advice given here. The risk of stopping Coumadin for a mechanical valve probably far exceeds the risk of stopping for coronary occlusive disease. Although you are anticoagulated during the surgery itself, this is reversed at the end of the procedure. You then go without any protection from anticoagulation for 24 hours and then begin Coumadin therapy and perhaps even heparin. The 24 hours post op are critical to trying to prevent bleeding episodes from the valve and the opening of the pericardial sac itself.
I cannot address the issue of a particular surgeon preferring a mechanical over porcine valve. There are definite differences in the construction of different mechanical and porcine valves that make insertion easier or harder for individual surgeons. This is more likely the reason. The surgeon has found a valve that he can insert well and gets good results. It jus happens in this case to be mechanical.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
