title: Isolated aortic valve replacement in patients with small aortic annulus-a high-risk group on long-term follow-up.
abstract: BACKGROUND
  Patients with small aortic annulus undergoing isolated aortic valve replacement face an often underestimated surgical risk. We describe initial clinical results and long-term follow-up of this particular high-risk group.
  
  
  METHODS
  Between January 1998 and December 2004, 148 consecutive patients with small aortic annulus underwent isolated aortic valve replacement by implantation of a Mitroflow Aortic Pericardial Heart Valve (Sorin S.p.A., Milano, Italy) 19 or 21 mm bioprostheses. Mean age was 75.4 ± 6.2 years. Female gender, obesity, and multiple comorbidities were predominant. Mean logistic euroSCORE for mortality was 18.5 ± 2.3%. Follow-up time was 7.2 ± 2.0 years, with a total of 1,066 patient years.
  
  
  RESULTS
  Postoperative course and outcome during follow-up were strongly influenced by extracardiac morbidities. Hospital mortality was 6.1%, 5-year survival 71.9%, and 10-year survival 40.9%. Most patients (70.0%) died because of extracardiac reasons. Significant reasons for death were age, pre-existing atrial fibrillation, diabetes mellitus type 2, chronic renal failure, extracardiac vascular disease, history of stroke, and preoperative presentation at Canadian Cardiovascular Society class III and IV (p < 0.05). Freedom from valve-related reoperation was 99.1% at 5 years and 93.4% at 10 years. Prosthesis-patient mismatch occurred in 12.2% and was not affected with any adverse outcome (p = nonsignificant). Echocardiographic data demonstrated a significant reduction of mean transvalvular gradients in all patients (61.2 ± 19.7 mm Hg preoperatively; 18.0 ± 8.0 mm Hg during follow-up; p < 0.05). All patients reported a significant improvement in New York Heart Association functional class (p < 0.05).
  
  
  CONCLUSIONS
  Patients with small aortic annulus are predominantly small, obese, and old-aged females with multiple comorbidities. Mitroflow valve avoids prosthesis-patient mismatch and provides excellent hemodynamics. Observed long-term results were disappointing, but they were mainly limited by extracardiac comorbidities and advanced age.
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany. manuel.wilbring@gmail.com
authors.forename: Manuel
authors.initials: M
authors.lastname: Wilbring
authors.forename: Konstantin
authors.initials: K
authors.lastname: Alexiou
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Schumann
authors.forename: Klaus
authors.initials: K
authors.lastname: Matschke
authors.forename: Sems Malte
authors.initials: SM
authors.lastname: Tugtekin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D001705:Bioprosthesis; D016009:Chi-Square Distribution; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D006439:Hemodynamics; D017052:Hospital Mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000401:mortality / Q000601:surgery; D011474:Prosthesis Design; D012086:Reoperation; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography