THE MITRACLIP DEVICE

Two weeks, one of our English national daily ( my patient did not tell me which one ), carried an press release by my colleagues at the IJN, stating that they have implanted the MitraClip device in some of their patients. Of course, the patients who asked me were also suffering from mitral incompetence, and they wondered whether they were candidates for the mitraclip device.
I suppose, I should begin by discussing about mitral incompetence. Mitral Incompetence is a condition where the mitral valve ( the left sided cardiac valve that channels blood from the left atrium to the left ventricle ) malfunctions and leaks. Between the early part of the 20 century, the most common cause was chronic rheumatic heart disease ( a post streptococcal condition affecting the heart valves, causing the valve apparatus to stick together, making them inefficient, not opening well and not closing well, almost like the valve is rusted. Over the years, we have been able to reduce the incidence of streptococcal infection, thereby also reducing the incidence of rheumatic heart disease. I am told that the public hospitals still see them, as they usually affect the lower social economic group who live in overcrowded conditions.
Nowadays, we see mitral incompetence caused by coronary heart disease and also mitral valve degeneration or the floppy mitral valve syndrome.
When the mitral valve leaks, when the left ventricle ( the power house of the heart ) contracts, the blood instead of being directed forward, only into the aorta by the left ventricle, is partly directed forward into the aorta, but some ( depending on the severity of the mitral incompetence ) is also allowed to regurgitates ( backwards ) into the left atrium. This makes the heart inefficient and stressed, and over months and years the heart enlarges, and slowly fails. The patient then develops heart failure, from which some succumb and die.


The standard medical treatment used to be cardiac surgery, using the heart-lung machine to stop the heart while maintaining an effective body circulation. With the heart arrested, the surgeon opens the heart and replace the defective valve with a tissue or mechanical valve.This is a good operation and the patient, after about 2-3 months of recovery, can resume normal life and function. Of course, mitral valve replacement carries a mortality of about 5% in the average center. It is a time tried surgery and we know alot about it. All cardiac surgeons are well trained to do this operation and over the years, the valves used are getting better and better.
In March 2011, at the spring meeting of the American College of cardiology meeting at Orlando, the US investigators presented the results of the EVEREST II trial. This was a study of 279 patients with severe mitral incompetence who were high risk for surgery. They were comparing one group who underwent open heart surgery with mitral valve replacement ( the standard treatment ) with the second group, who underwent a percutaneous insertion of a mitraclip device. After 24 months of follow-up, they found that the patients who had the mitraclip device did just as well ( borderline ) as those who underwent open heart surgery. The success rate was 66% in the open heart surgery group and 51% in the mitraclip group. Remember that these are high risk patients. The investigators concluded that mitraclip was just as group ( albeit marginally ) as the open heart surgery group.
A bit about the mitraclip. This is a device with the mitral valve clip crimped down and attached to the end of a catheter on a tube. The device is the inserted into the femoral vein, passed up into the right atrium, and delivered through a puncture across the interatrial septum into the left atrium and then opened across the mitral valve and the clip is deployed to clip the sub-mitral valvular apparatus, tightening them, to reduce mitral incompetence. Enough technical details. So boring.






Even before the EVEREST II results, the Europeans had already given the device CE mark approval. The US FDA, despite the fair EVEREST II results, have still not given FDA approval, so it is very much an investigational device. This is important, as I told the two patients. It is NOT yet standard treatment.
What is even more alarming were the reports that came out in April 2011, after the EVEREST II results, that there were three cases of part of the device breaking off, during the process of implantation and one patient died when they open him up, to retrieve the broken piece.
Probably, the most famous patient to have received the investigational device was the late Elizabeth Taylor, She died after about 2 years. I had a blog on that earlier.
So, it is important to note that this mitraclip device is still largely investigational, and they must improve on it. It has problems, which unless you are well trained in them, may cause harm. It is for use in patients who may not be able to withstand open heart surgery. It is expensive ( as can be expected ). ProbablyRM 100K or more. Open mitral valve replacement is still being performed. It has stood the test of time and is safe and well understood. cardiac aneasthesia has improved by leaps and bounds and patients recover much better and faster now.
The need to do something new and sensational must be balanced by the need to care for an individual who depend on you to make him better. First do no harm, has also stood the test of time.