Defining the efficacy of aortic root enlargement procedures: a comparative analysis of surgical techniques.
BACKGROUND
Aortic root enlargement (ARE) procedures are believed to allow implantation of larger valve prostheses; however, little evidence exists to support the specific efficacy of various techniques.


METHODS
Using a cadaveric model, 20 adult (72.4 ± 15.3 years) hearts were stratified into 4 groups based on annular diameter: <20 mm, 20-22 mm, 22-24 mm, and >24 mm. Each heart underwent an aortic valve replacement following a Nicks, Manougian, aortoventriculoplasty and modified Bentall procedure, with appropriate reversals between procedures.


RESULTS
All 4 groups experienced similar increases in annular diameter (P = 0.43) and prosthesis size implanted (P = 0.51) with each enlargement technique. The Nicks, Manougian, modified Bentall and aortoventriculoplasty procedures enlarged the annulus by 0.43 ± 0.45 mm, 3.63 ± 0.95 mm, 0.78 ± 0.65 mm, and 6.08 ± 1.19 mm, respectively (P < 0.001). No significant change in prosthesis size was observed after the Nicks procedure (P = not significant). Increases of 1.3 ± 0.5, 1.3 ± 0.5, and 2.7 ± 0.6 prosthesis sizes were achieved with the Manougian, modified Bentall and aortoventriculoplasty techniques respectively (P < 0.001).


CONCLUSIONS
ARE procedures appear equally efficacious in both small and larger aortic roots. Although all 4 ARE techniques increased the annular diameter, only the Manougian, modified Bentall and aortoventriculoplasty procedures allowed for the implantation of a larger prosthetic valve. The Nicks procedure, which is likely the most commonly performed ARE, does not allow for the implantation of a larger prosthesis. Surgeon preference and patient factors may help in selecting the most appropriate ARE technique, as the modified Bentall and Manougian procedures achieved similar increases in valve size.
Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada.
Katie L
KL
Losenno
Jill J
JJ
Gelinas
Marjorie
M
Johnson
Michael W A
MW
Chu
D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000473:pathology / Q000601:surgery*; D001021:Aortic Valve / Q000473:pathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000473:pathology / Q000601:surgery*; D002102:Cadaver; D006348:Cardiac Surgical Procedures / Q000379:methods*; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged