title: Clinical outcome of transcatheter aortic valve implantation in patients with low-flow, low gradient aortic stenosis.
abstract: BACKGROUND
  Low-flow, low-gradient aortic stenosis is associated with relevant postoperative mortality whereas conservative management results in dismal prognosis. We present the initial experience of low-flow, low-gradient aortic stenosis treated with transcatheter aortic valve implantation (TAVI).
  
  
  METHODS
  From June 2008 to December 2010 167 consecutive patients with native severe aortic stenosis and an excessive operative risk underwent TAVI. Of these, 15 patients presented with low-flow, low-gradient aortic stenosis (aortic valve area < 1 cm(2) , left ventricular (LV) ejection fraction < 40%, aortic mean gradient < 40 mm Hg). The CoreValve prosthesis 18-F-generation (Medtronic, Minneapolis, Minnesota) was inserted retrograde. Clinical follow-up and echocardiography were performed 6 months after procedure.
  
  
  RESULTS
  Patients with low-flow, low-gradient aortic stenosis (mean LV ejection fraction 32 ± 6%, mean aortic gradient 27 ± 7 mm Hg) had higher all-cause mortality 6 months after TAVI compared to patients without low-flow, low-gradient aortic stenosis (33% vs. 13%, P = 0.037). In the surviving 10 patients with low-flow, low-gradient aortic stenosis, LV ejection fraction increased (34 ± 6% before vs. 46 ± 11% 6 months after TAVI, p = 0.005) and more distance covered in the 6-minute walk test (218 ± 102 meters before vs. 288 ± 129 meters 6 months after TAVI, p = 0.038).
  
  
  CONCLUSIONS
  Our study suggests that TAVI is feasible in patients with severe co-morbidities and low-flow, low-gradient aortic stenosis. Within the first 6 months after treatment all-cause mortality was considerable high, but the surviving patients showed symptomatic benefit and significant improvement of myocardial function and exercise capacity.
authors.affiliation: Cardiology and Angiology, BG University-Hospital Bergmannsheil, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany. michael_gotzmann@web.de
authors.forename: Michael
authors.initials: M
authors.lastname: Gotzmann
authors.forename: Michael
authors.initials: M
authors.lastname: Lindstaedt
authors.forename: Waldemar
authors.initials: W
authors.lastname: Bojara
authors.forename: Aydan
authors.initials: A
authors.lastname: Ewers
authors.forename: Andreas
authors.initials: A
authors.lastname: Mügge
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000379:methods*; D015331:Cohort Studies; D015150:Echocardiography, Doppler; D005080:Exercise Test / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D005858:Germany; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000379:methods*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000379:methods; D011183:Postoperative Complications / Q000401:mortality / Q000503:physiopathology; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013318:Stroke Volume / Q000502:physiology; D015996:Survival Rate; D016896:Treatment Outcome