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.

Coagulation and the Vessel Wall in Pulmonary Embolism

“…[3][4][5] Resolution occurs by mechanical fragmentation, 6 through organization of the thromboembolus by invasion of endothelial cells (ECs), mononuclear cells, and fibroblasts leading to recanalization, and through endogenous thrombolysis. In 0.1%-9.1% [7][8][9][10][11][12][13][14][15][16] of cases, venous thromboemboli fail to resorb, thereby resulting in CTEPH or in permanent occlusion of the deep veins.…”

Red cell distribution width

“…1,2 Although the incidence of CTEPH is usually estimated to be <1% among patients with acute PE, [2][3][4] several studies have proposed that this low incidence was an underestimation and showed approximately 4%, a relatively high incidence of CTEPH after PE. [5][6][7] In addition, it has not been shown why some PE patients develop CTEPH and others do not.…”

Accuracy of chest radiography in predicting pulmonary hypertension: A case-control study

“…In Table 6 Radiographic findings in 397 subjects with and without COPD. our experience, perfusion lung scintigraphy should also be obtained for it allows detecting multiple segmental or lobar perfusion defects that are the hallmark of chronic thromboembolic pulmonary hypertension [24]. This is amenable of surgical repair if the organized clots are located in the proximal branches of the pulmonary circulation [1,2,8,10].…”