title: Residual perfusion defects in patients with pulmonary embolism are related to impaired fibrinolytic capacity.
abstract: BACKGROUND
  Few studies investigated the relationship between fibrinolysis abnormalities and residual pulmonary perfusion defects after acute pulmonary embolism (PE).
  
  
  OBJECTIVE
  To assess the fibrinolytic profile in patients with prior PE in relation to the extent of scintigraphically detectable residual perfusion abnormalities.
  
  
  METHODS
  We studied 71 consecutive patients with a prior episode of PE, who were examined after one year of the incident embolic event, and at least one month after anticoagulation withdrawal. They underwent lung scintigraphy to assess the recovery of pulmonary perfusion, echocardiography and chest radiography to look for signs of pulmonary hypertension. Clot formation and lysis were evaluated by two turbidimetric methods: Clot and Lysis Assay and Clot Lysis Time. We also measured the in vitro plasmin-mediated lysis of fibrin from purified fibrinogen, and the circulating levels of fibrinolytic inhibitors. The sample was split in two categories based on the extent of residual perfusion defects: <10% (n=53), ≥ 10% (n=18).
  
  
  RESULTS
  Patients with perfusion defects >10% had significantly longer lysis time (p<0.05), and higher levels of plasminogen activator inhibitor-1 (p<0.01) than those with perfusion defects <10%. The time interval between symptoms onset and PE diagnosis (time-to-diagnosis) was significantly longer in patients with perfusion defects >10% than in the others (p=0.005). In multivariate logistic regression, both lysis time and time-to-diagnosis were independently associated with perfusion defects >10% (p<0.001). None of the sampled patients had echocardiographic or radiologic signs of pulmonary hypertension.
  
  
  CONCLUSIONS
  Prolonged time-to-diagnosis and fibrinolysis imbalance are independent predictors of incomplete perfusion recovery after acute PE.
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy. Electronic address: dona.lami@tin.it.
authors: Donatella
authors: D
authors: Lami
authors: Department of Heart and Vessels, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.
authors: Anna Paola
authors: AP
authors: Cellai
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Emilia
authors: E
authors: Antonucci
authors: Department of Biochemical Sciences, University of Florence, Florence, Italy.
authors: Claudia
authors: C
authors: Fiorillo
authors: Department of Biochemical Sciences, University of Florence, Florence, Italy.
authors: Matteo
authors: M
authors: Becatti
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Elisa
authors: E
authors: Grifoni
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Caterina
authors: C
authors: Cenci
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Rossella
authors: R
authors: Marcucci
authors: Department of Heart and Vessels, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.
authors: Lucia
authors: L
authors: Mannini
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Massimo
authors: M
authors: Miniati
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Rosanna
authors: R
authors: Abbate
authors: Department of Experimental and Clinical Medicine, University of Florence, Florence Italy.
authors: Domenico
authors: D
authors: Prisco
mesh_terms: D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D001780:Blood Coagulation Tests; D005260:Female; D005342:Fibrinolysis / Q000187:drug effects; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D055420:Perfusion Imaging; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood; D011237:Predictive Value of Tests; D011652:Pulmonary Circulation; D011655:Pulmonary Embolism / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D015415:Biomarkers; D017395:Plasminogen Activator Inhibitor 1; C051321:SERPINE1 protein, human
keywords: Clot lysis time; Fibrinolysis; Pulmonary embolism; Residual perfusion defects