title: Transcatheter mitral valve-in-valve implantation in patients with degenerated bioprostheses.
abstract: OBJECTIVE
  This study reports the results of a series of transapical mitral valve-in-valve implantations and aims to offer guidance on technical aspects of the procedure.
  
  
  BACKGROUND
  Mitral valve reoperations due to failing bioprostheses are associated with high morbidity and mortality. Transcatheter techniques may evolve as complementary approaches to surgery in these high-risk patients.
  
  
  METHODS
  Six patients (age 75 ± 15 years) received transapical implantation of a balloon-expandable pericardial heart valve into a degenerated bioprosthesis (range 27 to 31 mm) in mitral position at our institution. All patients were considered high risk for surgical valve replacement (logistic EuroSCORE: 33 ± 15%) after evaluation by an interdisciplinary heart team. Procedural and clinical outcomes were analyzed.
  
  
  RESULTS
  Implantation was successful in all patients with reduction of mean transvalvular gradients from 11.3 ± 5.2 mm Hg to 5.5 ± 3.6 mm Hg (p = 0.016) and median regurgitation from grade 3.0 (interquartile range [IQR]: 2.7 to 3.1) to 0 (IQR: 0 to 1.0, p = 0.033) with trace paravalvular regurgitation remaining in 2 patients. Apical bleeding occurred in 2 patients requiring rethoracotomy in 1 and resuscitation in a second patient, the latter of whom died on postoperative day 6. In the remaining patients, median New York Heart Association functional class improved from 3.0 (IQR: 3.0 to 3.5) to 2.0 (IQR: 1.5 to 2.0, p = 0.048) over a median follow-up of 70 (IQR: 25.5 to 358) days.
  
  
  CONCLUSIONS
  With acceptable results in a high-risk population, transapical mitral valve-in-valve implantation can be considered as a complementary approach to reoperative mitral valve surgery in select patients.
authors.affiliation: Department of Cardiovascular Surgery, University Heart Center Hamburg, Hamburg, Germany. m.seiffert@uke.de
authors.forename: Moritz
authors.initials: M
authors.lastname: Seiffert
authors.forename: Lenard
authors.initials: L
authors.lastname: Conradi
authors.forename: Stephan
authors.initials: S
authors.lastname: Baldus
authors.forename: Johannes
authors.initials: J
authors.lastname: Schirmer
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Knap
authors.forename: Stefan
authors.initials: S
authors.lastname: Blankenberg
authors.forename: Hermann
authors.initials: H
authors.lastname: Reichenspurner
authors.forename: Hendrik
authors.initials: H
authors.lastname: Treede
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001705:Bioprosthesis; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D002404:Catheterization; D005260:Female; D005858:Germany; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000601:surgery*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography