Skipping Predilatation in Low-risk TAVR Patients Does Not Mar Outcomes

In severe symptomatic patients at low surgical risk, balloon predilatation during TAVR increases procedure time without providing any additional benefits, new data from the PARTNER 3 trial suggest.

Compared with no predilatation, clinical outcomes in patients who underwent predilatation were similar at 30 days and 1 year. The results were presented as part of the Featured Clinical Research session at the virtual TVT Connect meeting.

“There has been very conflicting evidence on the use of balloon predilation before putting in a TAVR valve, whether it is a self-expanding or a balloon-expanding valve, in low-risk patients who have very  minimal comorbidities and who, as a group, are at low risk for complications,” Karim Al-Azizi, MD (Baylor Scott & White Heart Hospital Plano, TX), told TCTMD. “What we found was that there was no significant effect in terms of death, stroke, or rehospitalization.” Additionally, not predilating did not increase the risk of needing postdilatation, which Al-Azizi said was reassuring.

Commenting on the study for TCTMD, Gilbert Tang, MD (Mount Sinai Health System, New York, NY), said the results add support for the notion that “in a low-risk population with favorable anatomy it is possible to simplify the TAVR procedure by skipping the step of predilatation without having an adverse effect on clinical outcomes.”

Very Few Differences Noted

The analysis included 495 low-risk patients (286 predilated). Patients with bicuspid aortic valves noted on CT imaging or severe calcification of the aortic valve complex, especially LVOT calcium, were excluded. Propensity-score matching was performed to create two cohorts of 202 patients each from the predilated and non-predilated groups.

Those who underwent predilatation had a mean procedure duration of 63.2 minutes versus 51.4 minutes for the non-predilatation group (P = 0.0014). Predilatation also was associated with longer total fluoroscopy time (15.6 vs 11.7 minutes; P < 0.0001). Other procedural variables, including anesthesia time, valve size, and annular area were not different between groups. Postdilatation was performed in 24.9% of those with predilatation and in 18.8% of those with no predilatation (P = 0.1495).

For the primary endpoint of death, stroke, or rehospitalization, there was no difference between the predilatation and no predilatation groups at 30 days (5.0% vs 4.0%) or 1 year (8.4% vs 10.4%; log rank P = 0.52). There also was no difference in the individual components of the primary endpoint or in CV death at 30 days or 1 year.

When the researchers assessed the endpoints according to whether patients did or did not receive postdilatation, there was no difference at 30 days or 1 year except for stroke. Among those who were postdilated, rates of all stroke at 1 year were higher than in those with no postdilatation (3.36% vs 0.39%; P = 0.0136).

Echocardiographic analyses that included mean gradient, peak gradient, effective orifice area, and LV ejection fraction indicated no differences between predilatation and no predilatation patients at 30 days or 1 year. Similarly, for the outcomes of paravalvular regurgitation and total aortic regurgitation at 30 days or 1 year, there were no significant differences.

Although quality of life (QoL), as assessed by the Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary score, was not significantly different from baseline to 30 days in the predilatation and no predilatation groups but appeared to favor the predilatation group at 1 year, a difference that reached statistical significance.

Questions About Stroke and QoL

To TCTMD, Tang said the higher rate of stroke in the postdilatation patients raises more questions than answers and will require additional analyses to clarify.  

“We know that stroke in TAVR is multifactorial, not just from the procedural standpoint, but also based on risk factors such as preexisting atrial fibrillation,” he said. “Based on just the presentation alone, I don't know if any of these balloon postdilatation patients had more baseline atrial fibrillation, for example, or new-onset atrial fibrillation.” Tang said late strokes are unlikely to be procedure-related, and noted that 2-year data from the full PARTNER 3 cohort shows more strokes in the TAVR group as compared with SAVR-treated patients.

“Another important issue to look at would be how many of those who had postdilatation had predilatation,” Tang said. “The message may be that rather than avoiding predilatation, that perhaps in a certain subset of patients, the severity of the calcification, the distribution of the calcification, may suggest a role for predilatation in these patients to avoid postdilation.”

Commenting on the apparent QoL advantage at 1 year in the predilatation group, Al-Azizi said the absolute KCCQ scores were not significantly different.

“When you look at the numbers, it's only the delta change from baseline that was significantly higher,” he said. Although it is difficult to say what, if anything, that means, Al-Azizi said it might reflect that some patients were more symptomatic at baseline than others.

“I'm not sure how much the procedure plays a role in terms of someone's quality of life afterwards,” Tang added. “We all know that depending on how you do statistical analyses that you often have statistically significant associations between certain variables and certain outcomes. In this case, the delta is so small . . . it really doesn't mean much on a clinical level.”