Sunday, April 9, 2017

When a Heart Valve Fails

It is 27 years this month since my husband's own bicuspid aortic valve was replaced. It had completely failed him, causing his entire heart to fail too.

Since that time, we know now that his body has struggled with the artificial valves that have kept him alive, aortic valves made by man. First a mechanical valve. Then a bovine tissue vale. And now, it is almost 6 weeks since he received his third artificial aortic valve.

Why another surgery? He was, quite simply, on the brink of losing his life. The 11 year old bovine prosthetic valve in his heart was failing.

The 2 leaflets at the bottom were completely frozen,
only the 1 leaflet at the top was moving to let blood flow
Tissue Valve Deteriorating at Eight Years
At 8 years, we were told that one of the leaflets was not moving well. Only 8 years?

We had hoped that he would be like many in his age group, whose bovine pericardial valves still function at 20 years.

Inside his body, for whatever the reason, the valve is considered a foreign invader, something that needs to be attacked or healed!

I had read that tissue valves like this last about 6 years in children, and that was the case for one teenager we know.

He had a transesophageal echo, and those findings was more hopeful. The one leaflet in trouble was moving enough to close completely, it just could not open all the way. Maybe it wasn't too bad, and would still last quite a long time.

Another Leaflet in Trouble

Late in 2016, with the valve approaching 11 years old, a "regular" echocardiogram, through the chest wall, showed that two leaflets were in trouble now. We had to face that it wasn't just one leaflet, and that this valve continued to deteriorate.

Surgery the Only Hope

My husband was not a candidate for TAVI (TAVR), the procedure where another valve is threaded up and inserted inside the old, failing valve. One of the reasons for that was that his aortic valve diameter is too small, only 21 mm, to accept another valve inside it.

There was another reason also, that would have prevented TAVI from helping him. On the bottom, or "intake" side of the valve, my husband had grown scar tissue, called pannus all around the ring of the valve. It is pictured on the left. Most of the tissue was cut away and sent to pathology, so only a small part of the softer tissue remains attached.

This tissue was also blocking blood flow. In order to have full blood flow, those failing valve leaflets, and the scar tissue attached to the valve ring, had to come out. There was no other way.

Today, understanding these things, I am surprised that my husband's heart and body had coped as long as it had.

I found a paper from surgeons in Japan, Subvalvular Pannus Overgrowth after Mosaic Bioprosthesis Implantation in the Aortic Position, that discusses this happening in some of their patients. There is a picture, Figure 1, that shows the ring of scar tissue below the valve. In the conclusion, it mentions that preventing this scar tissue formation is unsolved.

My husband also grew pannus and strands of tissue on his first prosthetic valve, a mechanical valve. My personal feeling is that there is something about his body's reaction to these "foreign" valves that causes it to want to heal. However, in the body's attempts to heal, it has hurt him.

I do not know how many people form scar tissue on their artificial valves. Perhaps some of them do not live long enough.

In any case, this is why time was no longer our friend, and the surgery door was our door of hope. 

No Solutions?

And that, in this year 2017, remains the challenge. There is still far too little that is understood about the tissue in some of those who are apparently most complex, like my husband, who were born with a bicuspid aortic valve. For the sake of generations following us, we need answers to these mysteries.

I am glad that physicians such as those in Japan have seen and published about this. I refuse to believe that there are no solutions to these problems, if only someone will look for them! 

No comments:

Post a Comment