Valve-in-Valve TAVR’s Safety Is Validated in Major Registry Study

Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) appears to be at least as safe as — and probably safer than — native valve TAVR, according to the observational STS/ACC TVT Registry study presented at the American College of Cardiology’s Annual Scientific Session (ACC.17) on March 18. The findings suggest that ViV TAVR deserves consideration as the treatment of choice for inoperable and perhaps for high-risk patients, the authors propose.

“Valve-in-valve TAVR is used for patients with a failed surgical bioprosthesis at high risk for a redo AVR,” says Cleveland Clinic interventional cardiologist E. Murat Tuzcu, MD, who reported the findings as a featured oral presentation at ACC.17. “While it’s well established that TAVR for native valve aortic stenosis is safe and effective for inoperable patients and those at high or intermediate surgical risk, data comparing valve-in-valve TAVR with native valve TAVR have not been available.”

Study design at a glance

To generate the first such comparative data, Dr. Tuzcu and colleagues from Cleveland Clinic and several other institutions mined the massive STS/ACC TVT Registry™ operated by the Society of Thoracic Surgeons and the ACC.

They identified all 1,476 ViV TAVR procedures in the registry from November 2011 through September 2015. After excluding cases not linked to the Centers for Medicare & Medicaid (CMS) database or with missing data or prior TAVR, there were 757 ViV cases for inclusion in the analysis. These cases were paired on a 1:2 simple matching basis with 1,495 cases of native valve TAVR from the registry during the same period. All patients had at least one year of outcomes data linked to CMS administrative claims.

The ViV and native valve groups were comparable in mean STS score (7.5 for each), but the ViV group was younger (median age of 79 vs. 84 years) and more male (61.4 vs. 54.4 percent).

Results: ViV superior across a range of outcomes

When the two groups were compared across a range of outcome measures, ViV TAVR was significantly superior to native valve TAVR on the following major safety outcomes:

• All-cause in-hospital mortality (2.3 percent with ViV vs. 4.1 percent with native valve; P = .03)
• All-cause one-year mortality (13.3 percent vs. 23.1 percent; P < .001)
• In-hospital stroke (0.4 percent vs. 2.1 percent; P = .002)
• Stroke at one year (2.0 percent vs. 4.3 percent; P = .002)

Rates of several complications were also significantly reduced with ViV TAVR versus native valve TAVR, including:

• Major bleeding (3.9 percent vs. 6.4 percent; P = .01)
• Vascular complications (2.4 percent vs. 4.0 percent; P < .05)
• Need for pacemaker (3.2 percent vs. 10.9 percent; P = .01)
• New-onset atrial fibrillation (2.8 percent vs. 6.0 percent; P = .001)

Rates of procedural complications were statistically comparable (and low) in the two groups, as was length of stay. But ViV TAVR patients were discharged home significantly more often and had lower readmission rates.

Post-TAVR echocardiography showed ViV TAVR to be associated with:

• Higher mean gradients relative to native valve TAVR (16 mmHg vs. 8 mmHg; P = .03)
• Lower rates of moderate or severe aortic regurgitation relative to native valve TAVR (2.8 percent vs. 9.5 percent; P = .05)
• Higher gradients in significantly stenotic prostheses and smaller transcatheter valves (≤ 21 mm)

Treatment of choice?

“This real-world analysis shows that valve-in-valve TAVR is a very safe procedure for patients who have previously placed surgical valves that are dysfunctional and causing problems,” says Dr. Tuzcu. “The death rate, the stroke rate and rates of almost all complications are lower than what we see with native valve TAVR, which is already well accepted.

“These results suggest that valve-in-valve TAVR should be considered as the treatment of choice for inoperable patients and perhaps also for patients at high surgical risk,” he adds, noting that careful patient selection is important to achieving optimal results. “Selection should take into account the size of the surgical prosthesis, the mode of failure and the type of transcatheter heart valve to be used.”

Dr. Tuzcu acknowledges the study’s limitations as an observational analysis with most information based on self-reported data from TAVR centers. Additionally, not all ViV TAVR patients from the registry could be linked to CMS data, and current practice may have evolved since the study’s cutoff in September 2015. “Future studies should directly compare ViV TAVR against redo surgical AVR for definitive conclusions,” he observes.