Transcatheter aortic valve implantation for high-risk patients with severe aortic stenosis: A systematic review.
OBJECTIVE
The present systematic review objectively assessed the safety and clinical effectiveness of transcatheter aortic valve implantation for patients at high surgical risk with severe aortic stenosis.


METHODS
Electronic searches were performed in 6 databases from January 2000 to March 2009. The end points included feasibility, safety, efficacy, and durability. Clinical effectiveness was synthesized through a narrative review with full tabulation of results of all included studies.


RESULTS
The current evidence on transcatheter aortic valve implantation for aortic stenosis is limited to short-term observational studies. The overall procedural success rates ranged from 74% to 100%. The incidence of major adverse events included 30-day mortality (0%-25%), major ventricular tachyarrhythmia (0%-4%), myocardial infarction (0%-15%), cardiac tamponade (2%-10%), stroke (0%-10%), conversion to surgery (0%-8%), moderate to major paravalvular leak (4%-35%), vascular complication (8%-17%), valve-in-valve procedure (2%-12%), and aortic dissection/perforation (0%-4%). The overall 30-day major adverse cardiovascular and cerebral events ranged from 3% to 35%. The mean aortic valve area ranged from 0.5 to 0.8 cm(2) before and 1.3 to 2.0 cm(2) after transcatheter aortic valve implantation. The mean pressure gradient ranged from 34 to 58 mm Hg before and 3 to 12 mm Hg after transcatheter aortic valve implantation. There was no significant deterioration in echocardiography measurements during the assessment period. Death rate at 6 months postprocedure ranged from 18% to 48%. No studies had adequate follow-up to reliably evaluate long-term outcomes.


CONCLUSIONS
The procedure has a potential for serious complications. Although short-term efficacy based on echocardiography measurements is good, there is little evidence on long-term outcomes. The use of transcatheter aortic valve implantation should be considered only within the boundaries of clinical trials.
Yan
Tristan D
TD
Department of Cardiothoracic Surgery, The University of Sydney, Royal Prince Alfred Hospital, Sydney 2050, Australia. Tristan.Yan@unsw.edu.au
Cao
Christopher
C
Martens-Nielsen
Julie
J
Padang
Ratnasari
R
Ng
Martin
M
Vallely
Michael P
MP
Bannon
Paul G
PG
D001021:Aortic Valve / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000601:surgery*; D006328:Cardiac Catheterization; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D012307:Risk Factors; D012720:Severity of Illness Index