title: Catheter-directed ultrasound-accelerated thrombolysis for the treatment of acute pulmonary embolism.
abstract: BACKGROUND
  Systemic thrombolysis rapidly improves right ventricular (RV) dysfunction in patients with acute pulmonary embolism (PE) but is associated with major bleeding complications in up to 20%. The efficacy of low-dose, catheter-directed ultrasound-accelerated thrombolysis (USAT) on the reversal of RV dysfunction is unknown.
  
  
  METHODS
  We performed a retrospective analysis of 24 PE patients (60 ± 16 years) at intermediate (n = 19) or high risk (n = 5) from the East Jefferson General Hospital who were treated with USAT (mean rt-PA dose 33.5 ± 15.5mg over 19.7 hours) and received multiplanar contrast-enhanced chest computed tomography (CT) scans at baseline and after USAT at 38 ± 14 hours. All CT measurements were performed by an independent core laboratory.
  
  
  RESULTS
  The right-to-left ventricular dimension ratio (RV/LV ratio) from reconstructed CT four-chamber views at baseline of 1.33 ± 0.24 was significantly reduced to 1.00 ± 0.13 at follow-up by repeated-measures analysis of variance (p < 0.001). The CT-angiographic pulmonary clot burden as assessed by the modified Miller score was significantly reduced from 17.8 ± 5.3 to 8.7 ± 5.1 (p < 0.001). All patients were discharged alive, and there were no systemic bleeding complications but four major access site bleeding complications requiring transfusion and one suspected recurrent massive PE event.
  
  
  CONCLUSIONS
  In patients with intermediate and high risk PE, low-dose USAT rapidly reverses right ventricular dilatation and pulmonary clot burden.
authors.affiliation: Thoracic Surgery, Louisiana Heart, Lung and Vascular Institute, Metairie, LA 70006, USA. tengelha@ejgh.org
authors.forename: Tod C
authors.initials: TC
authors.lastname: Engelhardt
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Taylor
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Simprini
authors.forename: Nils
authors.initials: N
authors.lastname: Kucher
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002404:Catheterization / Q000379:methods; D057785:Catheters; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000628:therapy*; D012189:Retrospective Studies; D015912:Thrombolytic Therapy / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed; D014464:Ultrasonic Therapy / Q000379:methods; D014463:Ultrasonography