Three-dimensional transesophageal echocardiography identified several significant predictors of aortic regurgitation after transcatheter aortic valve replacement, according to a study published online Jan. 5 in JACC Cardiovascular Imaging.
“This is the first study to demonstrate that large prosthetic expansion, elliptical prosthetic shape, and anti-anatomical position are 3D features associated with transvalvular AR,” said Dr. Kentaro Shibayama of Cedars-Sinai Heart Institute in Los Angeles, and his associates. The study also showed that paravalvular AR was inversely related to effective area oversizing, the investigators said (JACC Cardiovasc Imag. 2016 Jan. 6).
Post-TAVR AR continues to affect substantial numbers of patients, despite progress in prosthesis design. Past research has linked paravalvular AR to prosthetic undersizing, long-axis malpositioning, and aortic annular calcification, but the causes of transvalvular AR have not been adequately studied, the researchers said. Using intraprocedural 3D transesophageal echocardiography, they imaged the native annuluses and postoperative prosthetic valves of 201 patients with severe aortic stenosis who received the Edwards SAPIEN device. The investigators also used transthoracic echocardiography to separately grade post-TAVR transvalvular and paravalvular AR as none or trivial, mild, moderate, or severe according to the 2012 Valve Academic Research Consortium criteria (J Am Coll Cardiol. 2012;60:1438-54).Fully 44% of patients developed mild or moderate aortic regurgitation after TAVR, while the rest had no or trivial AR, the investigators said. About three-quarters of AR cases were mild, nearly 25% were moderate, and none were severe. Only 3% of patients had transvalvular AR only, 34% had paravalvular AR only, and 7% had both types of AR. Patients with post-TAVR transvalvular AR had significantly more prosthetic expansion (P less than .05), a more elliptical prosthetic shape at the level of the prosthetic commissure (P less than .01), and malpositioning of the prosthetic commissures in relation to the native commissures (P less than .001), compared with patients without transvalvular AR.
Patients were more likely to have paravalvular AR if they had a lower percentage of effective area oversizing, defined as the prosthetic frame area divided by the area of the native aortic annulus (odds ratio, 0.97; 95% CI: 0.93-0.99, P less than .05). “A mismatch between a larger native aortic valve annulus area and a smaller deployed prosthesis found by intra-procedural 3D TEE may increase the risk of developing mild or greater paravalvular AR,” the researchers explained. Older age also was slightly but significantly linked with mild or moderate paravalvular AR(OR, 1.05; 95% CI, 1.01-1.09, P less than .05).
“Abnormalities related to transvalvular AR after TAVR found in this study may contribute to further deterioration of the prosthesis, warranting careful prospective studies to assess the long-term prognosis of these patients,” the investigators concluded. They cautioned that the number of patients with post-TAVR transvalvular AR was too small to carry out detailed analyses.
The researchers reported no funding sources. Senior author Dr. Takahiro Shiota reported being a speaker for Philips Ultrasound, and three of the other seven coinvestigators reported financial relationships with Edwards, Medtronic, Abbott, Capricor, St. Jude Medical, Philips Ultrasound, and Venus Medtech.