TAVI Studies Published

July 19, 2011—Two studies of transcatheter aortic valve implantation (TAVI) were published in the Journal of the American College of Cardiology: Cardiovascular Interventions.

First, Marco Mussardo, MD, et al published findings from a study of periprocedural and short-term outcomes of transfemoral TAVI with the Sapien XT (Edwards Lifesciences, Irvine, CA) as compared with the Edwards Sapien valve (2011;4:743–750). The investigators concluded that the new Sapien XT valve has the same short-term performance as the Edwards Sapien valve but seems to be associated with a lower risk of major vascular complications and thus has a broader clinical application.

Second, Eberhard Grube, MD, et al published findings from a pilot study of the feasibility of TAVI without balloon predilation (2011;4:751–757). The investigators concluded that TAVI without balloon predilation is feasible and safe, resulting in similar acute safety and efficacy as the current standard approach of TAVI with predilation.

In the first study, the investigators stated that the background is that the Sapien XT has been recently commercialized in Europe, but there are no studies analyzing the efficacy and safety of the device compared with the Sapien valve.

As detailed in Journal of the American College of Cardiology: Cardiovascular Interventions, the study was composed of all consecutive patients (N = 120) who underwent TAVI in a single center via the transfemoral approach with either the Edwards Sapien valve (n = 66) or the Sapien XT valve (n = 54). Valve Academic Research Consortium endpoints were used. Mean age was 80 ± 8 years, and mean logistic EuroSCORE was 24.9 ± 17.0.

The investigators found that the iliofemoral artery minimal lumen diameter was smaller in patients treated with the Sapien XT (7.27 ± 1.09 mm vs 7.94 ± 1.08 mm; P = .002). Device success was high in both groups (96.3% vs 92.4%; P = 0.45). Major vascular events were threefold lower in the Sapien XT group (11.1% vs 33.3%; relative risk, 0.4; 95% confidence interval, 0.28–0.57; P = .004). Life-threatening and major bleeding events were not significantly different between groups (18.5% vs 27.3% and 35.2% vs 40.9%, respectively). The Sapien XT group had a lower 30-day Valve Academic Research Consortium combined safety endpoint (20.4% vs 45.5%; relative risk, 0.44; 95% confidence interval, 0.24–0.8; P = .004). The 30-day mortality was 1.7% (n = 2). At 30 days, mean transaortic gradient was approximately 10 mm Hg in both groups, and the aortic regurgitation was mild-to-moderate in 70.2% of Sapien XT and 76.3% of Edwards Sapien valve, reported the investigators.

The background of the second study in Journal of the American College of Cardiology: Cardiovascular Interventions is that balloon predilation of the stenosed aortic valve is currently believed to be a necessary step for valve preparation before device placement in patients undergoing TAVI and, therefore, is considered an obligatory part of the procedure. However, the investigators stated, clear evidence supporting this policy is lacking. In contrast, predilation might be responsible in part for distal embolizations as well as atrioventricular conduction disturbances seen during TAVI procedures.

As detailed by the investigators, a total of 60 consecutive patients (mean age 80.1 ± 6.4 years, 53% female, mean logistic EuroSCORE 23.3 ± 15.2%) undergoing TAVI using the self-expanding CoreValve prosthesis (Medtronic Inc., Minneapolis, MN) have been prospectively enrolled at 13 international centers.

According to the investigators, the preprocedural mean transaortic valve gradient was 47.8 ± 15.5 mm Hg, and the mean effective orifice area was 0.67 ± 0.15 cm². The technical success rate was 96.7% (58 of 60 patients). Postdilation was performed in 16.7% (10 of 60) of patients. Postprocedural mean valve gradient was 4.4 ± 2.0 mm Hg. Circular and noncircular valve configuration was present in 41 and 19 cases (68.3% vs 31.7%), respectively, with similar effective orifice areas (1.74 ± 0.10 cm² vs 1.71 ± 0.22 cm²; P = NS). In-hospital mortality, myocardial infarction, stroke, and major vascular complications occurred in 6.7% (4 of 60), 0%, 5%, and 10% of patients. There was no valve embolization. New permanent pacing was needed in 11.7% (7 of 60) of patients, the investigators reported in Journal of the American College of Cardiology: Cardiovascular Interventions.