Transcatheter Aortic Valve Thrombosis: Incidence, Predisposing Factors, and Clinical Implications

J Am Coll Cardiol. 2016 Nov 8;68(19):2059-2069. doi: 10.1016/j.jacc.2016.08.010. Epub 2016 Aug 28.

Abstract

Background: There are limited data on the incidence, clinical implications, and predisposing factors of transcatheter heart valve (THV) thrombosis following transcatheter aortic valve replacement (TAVR).

Objectives: The authors assessed the incidence, potential predictors, and clinical implications of THV thrombosis as determined by contrast-enhanced multidetector computed tomography (MDCT) after TAVR.

Methods: Among 460 consecutive patients who underwent TAVR with the Edwards Sapien XT or Sapien 3 (Edwards Lifesciences, Irvine, California) THV, 405 (88%) underwent MDCT in addition to transthoracic and transesophageal echocardiography 1 to 3 months post-TAVR. MDCT scans were evaluated for hypoattenuated leaflet thickening that indicated THV thrombosis.

Results: MDCT verified THV thrombosis in 28 of 405 (7%) patients. A total of 23 patients had subclinical THV thrombosis, whereas 5 (18%) patients experienced clinically overt obstructive THV thrombosis. THV thrombosis risk did not differ among different generations of THVs (8% vs. 6%; p = 0.42). The risk of THV thrombosis in patients who did not receive warfarin was higher compared with patients who received warfarin (10.7% vs. 1.8%; risk ratio [RR]: 6.09; 95% confidence interval [CI]: 1.86 to 19.84). A larger THV was associated with an increased risk of THV thrombosis (p = 0.03). In multivariable analysis, a 29-mm THV (RR: 2.89; 95% CI: 1.44 to 5.80) and no post-TAVR warfarin treatment (RR: 5.46; 95% CI: 1.68 to 17.7) independently predicted THV thrombosis. Treatment with warfarin effectively reverted THV thrombosis and normalized THV function in 85% of patients as documented by follow-up transesophageal echocardiography and MDCT.

Conclusions: Incidence of THV thrombosis in this large study was 7%. A larger THV size may predispose to THV thrombosis, whereas treatment with warfarin appears to have a protective effect. Although often subclinical, THV thrombosis may have important clinical implications.

Keywords: aortic stenosis; multidetector computed tomography; platelet aggregation inhibitors; transcatheter aortic valve replacement; warfarin.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aortic Valve / diagnostic imaging*
  • Aortic Valve / surgery
  • Aortic Valve Stenosis / diagnosis
  • Aortic Valve Stenosis / surgery*
  • Denmark / epidemiology
  • Echocardiography, Transesophageal
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Male
  • Multidetector Computed Tomography
  • Postoperative Complications / diagnosis
  • Postoperative Complications / epidemiology*
  • Postoperative Complications / etiology
  • Prognosis
  • Retrospective Studies
  • Thrombosis / diagnosis
  • Thrombosis / epidemiology*
  • Thrombosis / etiology
  • Transcatheter Aortic Valve Replacement / adverse effects*