Predilatation or No Predilatation in TAVR? European Series Offers Reassurances Both Ways

Patients undergoing transcatheter aortic valve replacement without balloon predilatation have a higher rate of early adverse clinical events, namely stroke, when compared with individuals undergoing balloon aortic valvuloplasty prior to device implantation, according to the results of a single-center study. 

At 1 year, however, the rate of MACCE was not statistically different among patients who received balloon valvuloplasty prior to TAVR and those who did not. The incidence of stroke at 1 year was significantly higher among those without prior balloon valvuloplasty, although the increase was driven by a higher stroke rate within the first 30 days.

“We found, overall, when you looked at things like mortality and myocardial infarction, with those complications, there was no real difference,” Azeem Latib, MD (San Raffaele Scientific Institute, Milan, Italy), one of the study investigators, told TCTMD. “The one thing that concerned us a little bit—and we tried to understand it a bit better—was the early stroke rate. We did see at 30 days a difference in stroke in the no-predilatation group.”

In the paper, which is published April 21, 2016, in the American Journal of Cardiology, lead investigator Matteo Pagnesi, MD (San Raffaele Scientific Institute, Milan, Italy), and colleagues point out that balloon valvuloplasty has historically been considered part of the TAVR procedure, with operators performing predilatation to ensure adequate apposition of the valve, to facilitate crossing, and to ensure optimal expansion of the device. As they point out, though, any extra steps performed during a procedure increase the risk for complications.

For Guilherme Attizzani, MD (University Hospitals Harrington Heart and Vascular Institute, Cleveland, OH), who was not involved in the study, the data are reassuring from another perspective, namely that they show the use of balloon valvuloplasty is safe. “Although this is a relatively small study to show differences in clinical outcomes, at least there is no sign of harm with predilatation,” Attizzani told TCTMD.

There are three general concerns with balloon predilatation prior to TAVR. The first is the risk of damage or rupture of the LV outflow tract in patients with highly calcified aortic valves. While predilatation can help “crack” some of the calcium and open room for the new valve, a too-large balloon can rupture the aortic annulus, said Attizzani. Other concerns include the risk of stroke—although he stressed there are no data to confirm this—and clinical instability resulting from aortic regurgitation caused by predilatation.

Overall, Attizzani said that with careful preprocedure planning, the potential complications of predilatation are very rare. If physicians are conservative in their selection of balloon size, the risks can be minimized, he said.

Data at 30 Days and 1 Year

To TCTMD, Latib explained that as TAVR changed—with better devices, improved physician proficiency—operators, particularly European operators, have moved toward a less invasive approach. To make the procedure quicker, easier to perform, and to minimize the amount of manipulation performed at the aortic valve, one aspect of care that changed was to perform the procedure without predilatation. Initially, operators began to experiment with implanting the self-expanding CoreValve without balloon valvuloplasty, but as the Sapien 3 became available, centers began implanting this device, too without predilatation.

“In our practice in San Raffaele, where we do a lot of TAVR, we’ve tried it both ways, and we were a little bit confused in the end,” he said. “We tried both ways and we weren’t really sure one way or the other. When we looked at the published literature, there were some publications saying that if you predilate, you can cause more stroke and more conduction disturbances.” Others, including one German study, suggested that stroke rates were higher without valvuloplasty.

This led to their study, a retrospective analysis of clinical outcomes at one year in 517 patients undergoing TAVR via the transfemoral route, including 326 who underwent balloon predilatation prior to the procedure and 191 who underwent TAVR without prior valvuloplasty. Among those treated, 246 received the self-expanding CoreValve/Evolut R (Medtronic) and 271 received the balloon-expandable Sapien XT/Sapien 3 (Edwards Lifesciences) prostheses. The decision to perform balloon predilatation was left to the operator’s discretion.     

At 30 days, the rate of MACCE was 7.3% among individuals not receiving balloon valvuloplasty prior to TAVR compared with 3.4% in those treated with balloon predilatation prior to the procedure. The difference in MACCE was driven by a significant increase in the risk of stroke at 30 days. Just one stroke occurred in those undergoing balloon predilatation prior to TAVR compared with seven strokes in patients treated without predilatation.

At one year, the MACCE rate was similar among individuals treated with and without balloon predilatation, and while the stroke rate was statistically higher, all seven strokes in the patients without predilatation occurred within the first 30 days.

In a propensity-matched analysis that accounted for the differences in baseline clinical characteristics, comorbid disease, and surgical risk, the 30-day and 1-year clinical outcomes were similar among patients who received balloon valvuloplasty prior to TAVR and individuals who were not treated with predilatation. Numerically, there was a trend toward more strokes in the no-predilatation arm, but Latib stressed that the baseline characteristics of the two groups—predilatation versus no-predilatation—are very different and the differences might not have been entirely captured in the propensity-matched analysis.

“What it says to me is that there probably is not a large price to pay either way, but there may be a hint of some more neurological events if you don’t predilate,” he said. “I think what we really do need now are studies where we look at this in randomized way. My own feeling on this is that in the end there won’t be a standardized approach—we won’t ever say, you have to predilate all the time or you shouldn’t predilate all the time. I think we’ll learn from these types of studies that there might be some patients who do better with predilatation and others we might be able to avoid it to decrease complications.”

For example, individuals with more calcified valves, those with higher mean pressure gradients, or those with smaller valve areas, might need to predilatation to create space for the new prosthesis. 

The researchers also analyzed clinical outcomes based on the type of prosthesis implanted and whether or not predilatation was performed. At 30 days, the higher MACCE rate observed in the patients without balloon predilatation was driven by strokes in patients with a self-expanding valve, with six of the seven strokes occurring in this group. At 1 year, there was a trend toward a higher stroke rate in the no-predilatation group treated with a self-expanding valve, but the difference was not statistically significant (compared with the predilatation group treated with the same self-expanding valves).

The researchers caution that these findings may have been due to chance, since two recent studies evaluating the 30-day outcome after CoreValve implantation found no differences in mortality, stroke or MI. For the balloon-expandable valves, there was no difference in the 30-day or 1-year clinical outcomes between those who received predilatation and those who did not before undergoing TAVR.

Overall, the rate of postdilatation after TAVR was significantly higher among individuals who did not receive predilatation.

In Clinical Practice

Speaking with TCTMD, Attizzani explained that the use of predilatation prior to TAVR is dependent on the valve selected. For the balloon-expandable Edwards valves, predilatation is pretty much standard, although it does vary from operator to operator.

“The way we grew up implanting these valves initially was with predilatation for all cases with the balloon-expandable valves,” he said. “With the new generation valves, with the Sapien 3, because it’s a very stable deployment, there are some operators doing TAVR without the predilatation. The formal recommendation for the Sapien 3 valve is to do predilatation—I do predilatation for all my cases with the Sapien 3 valve.”

With the self-expandable valve, however, it’s a different story, he said. This valve can be implanted without balloon valvuloplasty. While there are groups who advocate that nearly every patient can undergo TAVR with the self-expanding valve without predilatation, Attizzani said that predilatation can help in certain patients, such as those with highly calcified aortic valves or those with a very small valve area. At present, he uses balloon valvuloplasty prior to TAVR with the self-expandiing valve in 40% to 50% of patients. 

Regarding the trend toward higher stroke rates among patients treated with a self-expanding valve who did not undergo predilatation, Attizzani agreed with the researchers, noting it is a subgroup analysis with very small numbers.  

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