title: Survival and restoration of pulmonary perfusion in a long-term follow-up of patients after acute pulmonary embolism.
abstract: We followed prospectively 834 consecutive patients (70% inpatients), evaluated for suspected pulmonary embolism, for a median time of 2.1 years (range, 0-4.8 yr), and compared the survival rates in patients with proven pulmonary embolism (n=320) with those without (n=514). In multivariate analysis, we modeled the probability of surviving in patients with pulmonary embolism as a function of the extent of pulmonary vascular obstruction at baseline. Among patients with pulmonary embolism, a scintigraphic follow-up was pursued to assess the restoration of pulmonary perfusion over a 1-year period. We found that massive pulmonary embolism (vascular obstruction>or=50%) is a risk factor for mortality within the first few days after onset but, subsequently, has no significant effect on survival. The adjusted risk of death in patients with massive pulmonary embolism was 8-fold higher than in patients without embolism within the first day after the incident event. By contrast, the adjusted risk of death for patients with minor or moderate pulmonary embolism (vascular obstruction<50%) was no higher than in patients without embolism at any time after onset. Most of the patients who survived a year after pulmonary embolism showed a nearly complete restoration of pulmonary perfusion with a considerable improvement in arterial oxygenation. Four (1%) of the 320 patients with pulmonary embolism at presentation developed chronic thromboembolic pulmonary hypertension. These patients featured persistent large perfusion defects in sequential lung scans. Pulmonary embolism with vascular obstruction>or=50% is a strong, independent predictor of reduced short-term survival. This underscores the need for a prompt diagnosis of the disease. Monitoring the resolution of pulmonary embolism by lung scanning may prove useful in identifying patients with persistent perfusion abnormalities who may be at risk of chronic thromboembolic pulmonary hypertension.
authors.affiliation: From Istituto di Fisiologia Clinica del Consiglio Nazionale delle Ricerche (MM, SM, ES, CB, LT, AD), Pisa, Italy; Dipartimento Cardio-Toracico (CG), Universita` degli Studi di Pisa, Pisa, Italy; Dipartimento Area Critica Medico-Chirurgica (MM), Universita` degli Studi di Firenze, Firenze, Italy; Arnold School of Public Health (MB), University of South Carolina, Columbia, South Carolina, United States.
authors.forename: Massimo
authors.initials: M
authors.lastname: Miniati
authors.forename: Simonetta
authors.initials: S
authors.lastname: Monti
authors.forename: Matteo
authors.initials: M
authors.lastname: Bottai
authors.forename: Elvio
authors.initials: E
authors.lastname: Scoscia
authors.forename: Carolina
authors.initials: C
authors.lastname: Bauleo
authors.forename: Lucia
authors.initials: L
authors.lastname: Tonelli
authors.forename: Alba
authors.initials: A
authors.lastname: Dainelli
authors.forename: Carlo
authors.initials: C
authors.lastname: Giuntini
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000453:epidemiology / Q000209:etiology; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011652:Pulmonary Circulation; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000401:mortality* / Q000503:physiopathology; D011877:Radionuclide Imaging; D012008:Recurrence; D012307:Risk Factors; D015996:Survival Rate