TAVI : UPDATES FROM PCR LONDON VALVES 2011

Last week saw the commencement of the PCR London Valves summit in London. The UK boys were out in large numbers to present their UK TAVI registry. As we all know TAVI stands for Transcatheter Aortic Valve Implantation. Also present were the Italians led by Dr Antonio Colombo, and the French TAVI registry was presented as well.
Anyway, the London boys ( UK TAVI ) presented their registry of 877 patients followed up to 2 years. There were 877 when they started in enrollment from January 2007, till Dec 2009. And by Dec 2010, 213 patients have reached 2 years followup. They were using mainly the two market leaders, the Sapien Valve from Edwards lab., and the Corevalve from Medtronic International. They were both equally good. We did learn a lot from their presentations and the subsequent presntations as well.

First the 2 year results.

End point	CoreValve (%)	Sapien (%)	p
30-d mortality	5.8	8.5	0.11
1-y mortality	21.7	20.6	0.68
2-y mortality	23.9	28.3	0.14
Moderate/severe aortic regurgitation	17.3	9.6	0.001
Conversion to surgery	0	1.5	0.01*
Pacemaker implantation	24.4	7.4	<0.001
Repeat procedure	1.6	0	0.02*

Sure looks like the two valves are just as good and just as safe. I suppose the obvious point to learn is that the 1 year mortality is significantly more than the 30 day mortality. We all wonder why. After 1 year, the mortality flattens out again. Basically, at 1 year, about a third would have died. I also learn that the replaced valves can leak giving rise to the need for a re-do in some patients. There is also the need for pace maker implantation as the aortic valve ring is very near the conduction bundles and can be injured.

Following this UK TAVI presentation ( incidentally the paper is also out in the Oct 19th online edition of Journal of the American College of Cardiology ), the other papers also presented the registries of individuals and countries.
Dr Daniel Blackman of Sussex Heart Center, presented his experience with 1,600 patients with 1 year follow-up.

His results merits some close observation.

Outcome	Edwards transfemoral, n=389 (%)	CoreValve transfemoral, n=706 (%)	p	Edwards transapical, n=409 (%)	CoreValve subclavian, n=91 (%)	p
30-d mortality	4.3	5.2	NS	11.2	4.4	<0.01a
12-mo survival	84.5	80.8	0.453	74.5	75.4	<0.001b
New permanent pacemaker	6.2	21.6	<0.001	5.6	22.1	<0.001
Aortic regurgitation >2	8.4	13.4	0.015	6.4	9.5	0.34

Very interesting. As we all know, the Sapien Valve can be implanted transapical, or trans-femoral, while the Corevalve can be implanted trans-femoral or trans-subclavian. In Dr Blackman's experience, they were 50% with the Corevalve and 50% with the sapien valve. These different routes obviously have to do with patients fitness for the procedure ( Euroscore ) or the availability of access sites. Anyway, the London Blackman's experience seemed to suggest that those by the trans-femoral route do the best, be it with the Sapien or Corevalve. There is again the 30 days low mortality and morbidity, and the rise in mortality at 12 months. Those done through the transapical route do the worse. Those done through the trans-subclavian route do well like the trans-femoral, but catchup over 12 months to be like the transapical. Interesting observations.

I do not do and will not learn to do TAVI, as I believe that interventionist do best for their patients that which they do all the time. In their recommendation during the PCR London Valve 2011, doctors who do 3-5 per week are recognised as competent, and those that do less are under training. I do not see TAVI, which cost USD 30,ooo currently, as something that I will get to do 3 times a week, so I will leave it to the younger boys and the centers of excellence, who I hope will do 3-5 per week, and not 3-5 a year. I understand that as we were holding our ICF 2011 meeting in Kuching, a TAVI meeting was taking place at an institution in Kuala Lumpur. This is where my fear is. That the experts come and give talks, and physicians ( interventionist ), see one or two cases and try it when they get back home, and then use unsuspecting patients as their guinea pigs, as they try and get over their learning curve. I do not think that this is fair, as the patients have no way of knowing that someone is actually trying it out on them. This is one of my greatest fear, as I observe the interventional scene unfold in Malaysia.

The US FDA have asked for all the clinical papers on the Sapien velve as Edwards Lab has filed for approval. Both the Sapien and Corevalve has received CE mark approval and are current in use in Europe. That is why, most of the experience and data is coming out of Europe.
Well, I suppose the TAVI does have a role to play in patients who are too ill for Aortic Valve Surgery. I only hope that the phrase " too ill for surgery" will not be misused by physicians and patients for their own gains. That is always the danger with less invasive surgical procedures.