The major takeaways are that TAVR has been a great procedure for those who are at high risk for surgical AVR. We all now know that even in intermediate and low risk, it’s also a very good, viable option vs. surgery.
The quest of this study was to determine in some of the highest-risk patients — those with renal disease who undergo dialysis — if TAVR would also be very helpful in reducing morbidity and mortality in this group.
The interesting findings were that although there was a reduction in some of the morbidities and mortality compared to what has been projected or seen in the past on dialysis patients that had surgical AVR, it was not as much as we would have hoped. In other words, the mortality was still high.
One has to be a little bit wiser in the selection of patients with renal failure with or without dialysis going to TAVR, and not presume that it’s going to be safe and low risk. It just means that we need a heart team approach and to incorporate the patient in the shared decision-making process, and to realize that yes, it may be less risky than surgery, but it’s still going to be a significant risk.
To be specific, we saw that the in-hospital mortality was certainly higher than those who didn’t have dialysis, and the 1-year mortality was quite significant at 37%. Studies in the past have suggested that patients on dialysis that have surgical AVR may have an even higher mortality; even as much as 50%. But still, a mortality rate of 37% is quite high. That gives us pause before we think that TAVR is going to be the answer for renal patients. It still has to be done very judiciously in this group.
The other factors were that patients on dialysis had higher rates of major bleeding, as is usual with most procedures and surgeries in that population. That’s one of the morbidities that we can expect as well. Despite TAVR being relatively less invasive than surgical AVR, there were still significant rates of bleeding and also some major vascular complications.
It just has to be put into context that it needs to be a sanguine decision made by a heart team involving the family before one uses this procedure, albeit TAVR still may be safer and less risky than surgical AVR.
Some of the specifics are that the patients that were on dialysis were younger and more commonly diabetic and hypertensive, which are comorbid conditions that might lead to higher risk. The young age didn’t protect them from these other comorbid conditions or from having higher rates of complications.
The major thing is that patients with renal disease or dialysis that undergo TAVR do have higher risk than the non-dialysis patients in terms of their bleeding and their mortality. TAVR is not an easy answer for dialysis patients either.
This study was done with the TVT registry, and more than 70,000 patients were reviewed to garner about 2,000 renal patients that were evaluated. These ACC/STS/TVT/NCDR registries are fantastic for being able to look at specific groups and see if we can find types and subtypes that might benefit from procedures.
In this case, if we looked at further research, we might try to explore if any sungroups of patients on dialysis might be safer with TAVR, especially if they don’t have any significant other comorbidities like diabetes and hypertension. We can continue to use these vast registries to search for particular subgroups that actually may benefit from TAVR even in the chronic kidney disease population.
This study is a great example of the power of these registries in being able to answer questions. As was put in the prologue, there have been studies in the past that had showed that maybe dialysis patients do better with TAVR. In fact, those studies did not provide a definitive answer because of the sample size. This study points out the power of the registries for answering questions vs. isolated smaller studies.
B. Hadley Wilson, MD, FACC
Sanger Heart & Vascular Institute, Atrium Health
Clinical Professor of Medicine
UNC School of Medicine
Member, Board of Trustees, American College of Cardiology
Disclosures: Wilson reports no relevant financial disclosures.