Roundup: Latest Research on TAVR

At the Southern Thoracic Surgical Association 65th Annual Meeting & Exhibition, several speakers presented recent research on the use of transcatheter aortic valve replacement (TAVR).

Keith Allen, MD, of St. Luke’s Mid America Heart Institute in Missouri, presented research that found TAVR using transcarotid (TC) access led to better outcomes compared with transapical (TA) or transaortic (TAo).

In the study, researchers retrospectively assessed 149 patients who underwent non-femoral TAVR with TC (n = 68), TA (n = 48), and TAo (n = 33) access, analyzing outcomes including in-hospital/30-day mortality, blood product transfusion, and discharge status.

TC, TA, and TAo access patients had similar median Predicted Risk of Mortality (PROM) using the transcatheter valve therapy (9.0% vs. 8.8% vs. 10.0%) and Society of Thoracic Surgeons (STS; 10.0% vs. 9.1% vs. 10.0%) risk calculators, respectively. TC patients were more likely to have cerebral (P<0.001) and peripheral vascular (P=0.008) disease, chronic lung disease (P=0.03), and prior stroke (P=0.05). TC, TA, and TAo access patients had similar rates of in-hospital mortality (2.9% [n=2/68] vs 2.1% [n=1/48] vs 6.1% [n=2/33]), 30-day mortality (4.4% [n=3/68] vs 6.3% [n=3/48] vs 15.2% [n=5/33]), and 30-day stroke (2.9% [n=2/68] vs 2.1% [n=1/48] vs 3.0% [n=1/33]). However, TC access was associated with significantly better Kaplan-Meier one- (94.4% vs 83.3% vs 69.7%) and two-year (87.0% vs 77.0% vs 63.6%) survival, as well as shorter median length of stay (3.0 vs 6.5 vs 7.0 days).

Melissa Levack, MD, of the Cleveland Clinic in Ohio, discussed her research on permanent pacemaker implantation (PPI) in patients undergoing surgical aortic valve replacement (SAVR) and TAVR.

Researchers evaluated preoperative variables and baseline electrocardiograms for 11,195 patients who were undergoing isolated SAVR and/or coronary artery bypass grafting (CABG; n=9,903) or TAVR and/or percutaneous coronary intervention (n=1,2920) between 1996 and 2016. Researchers excluded patients with endocarditis, previous PPI, prior documentation of complete heart block, emergency surgery, or other surgical procedures.

Overall, PPI was required in patients undergoing isolated SAVR (6%), SAVR and CABG (7.3%), and of isolated TAVR (11%). PPI rate for SAVR decreased from 13% to 3.1%. From 2006 throughout the remainder of the study period, the SAVR PPI rate was 4%. PPI risk factors following TAVR included preoperative conduction disturbances, type of valve (SAPIEN = 11%; SAPIEN XT = 7%; SAPIEN 3 = 12%; CoreValve = 31%; and other TAVR = 11%), and left main stenosis. PPI risk factors after SAVR were preoperative conduction disturbances, older age, and earlier date of operation. Researchers did not observe an association between PPI and bicuspid valves, mechanical versus bioprosthetic valves, STS risk score and concomitant CABG.

The authors wrote, “At a high-volume institution in the current era, establishing a baseline for PPI rates is necessary. Preoperative conduction disturbances and valve type affect the rate of PPI. STS risk scores did not affect PPI rates. These data provide a benchmark that should be taken into account when considering TAVR in low-risk patients.”

Kristen A. Sell-Dottin, MD, of the University of Louisville in Kentucky, discussed the impact of bicuspid and tricuspid aortic stenosis (AS) on TAVR outcomes. Researchers evaluated 25 patients with bicuspid AS and 428 patients with tricuspid AS from a single institution. After propensity score matching (1:2), there were 22 pairs of patients.

Mean age was similar for bicuspid (69.9 years) and tricuspid (70.5 years) patients (P=0.9), as was the percentage of female patients (36% and 32%, respectively).

Patients undergoing bicuspid AS were younger and had lower STS risk scores, as well as increased annular velocity size. This cohort also had higher procedural fluoroscopy times and radiation doses compared with patients undergoing tricuspid AS. However, clinical outcomes were similar between the groups.

Among propensity-matched patients, the bicuspid cohort had longer procedure times. However, both cohorts had similar rates of mortality, major vascular complications, stroke, renal failure, and need for a pacemaker. Perivalvular leak rates were similar between the bicuspid (5%) and tricuspid (3%) cohorts (P=0.9). Those undergoing bicuspid AS had longer intensive care unit lengths of stay (23 days vs 7.7 days; P=0.5).

Although patients undergoing bicuspid AS present unique challenges, the researchers stated that the results show similar clinical outcomes to tricuspid AS group. “Appropriately selected intermediate- and high-risk bicuspid AS patients should be reasonably considered for TAVR,” the authors concluded.