Mostbeck A
Ludwig Boltzmann-Institut für Nuklearmedizin, Wien.
Wien Med Wochenschr. 1999;149(2-4):72-5.
The frequency of pulmonary embolism in patients with deep vein thrombosis can be assessed by pathological-anatomical and by nuclear medical studies. The frequency of deep vein thrombosis in autopsies ranges from 23.7% to 62%, by inclusion of microscopic thrombi the frequency increases to 72%. In most cases the localisation of the venous thrombosis is bilateral. In cases of venous thrombosis the frequency of pulmonary embolism is 52 to 79.4%, if microscopic thrombi are included, the number is 87.8%. 7.8% to 78.9% of all pulmonary emboli are considered as cause of death or severely contributing to death. The fatal embolisms originate preferentially from iliofemoral thrombosis. About 1/10 of all emboli originate from V. cava sup. and the right heart. In a small number of pulmonary emboli the origin could not be detected. The rate of correct intra vitam diagnosis is low, not more than 11 to 25% of all pathological-anatomical proven emboli had a correct diagnosis during life. In fatal pulmonary embolism the correct clinical diagnosis was made in 1/3. In nuclear medicine studies pulmonary embolisms are searched for from the clinical suspicion or the diagnosis of deep vein thrombosis with the perfusion-/ventilation- or inhalation scintigraphy. Patients with deep vein thromboses showed in 38 to 57.9% pulmonary embolism. In 80% of all pulmonary embolism multiple perfusion defects (2 to 9 perfusion defects) were detected, the lesions were evenly distributed in both lungs. The frequency of pulmonary embolism in calf vein thrombosis was 46%, in leg vein thrombosis 67% and reached 77% if the pelvic veins were involved. It is remarkable that the majority of all pulmonary emboli (46.3% to 100%) showed no clinical symptoms. The knowledge about the high frequency of pulmonary embolism in patients with deep vein thrombosis can improve the diagnosis of pulmonary embolism. For the diagnostic process of pulmonary embolism the presence of acute deep vein thrombosis increases the pre-test probability (prevalence of more than 50%). Every positive test for pulmonary embolism will gain a very high post-test probability according to Bayes' theorem.
深静脉血栓形成患者中肺栓塞的发生率可通过病理解剖学和核医学研究进行评估。尸检中深静脉血栓形成的发生率在23.7%至62%之间，若将显微镜下的血栓包括在内，发生率可增至72%。大多数情况下，静脉血栓形成的部位是双侧的。在静脉血栓形成的病例中，肺栓塞的发生率为52%至79.4%，若包括显微镜下的血栓，这一数字为87.8%。所有肺栓塞中有7.8%至78.9%被认为是死亡原因或严重促成死亡。致命性栓塞优先起源于髂股静脉血栓形成。所有栓塞中约十分之一起源于上腔静脉和右心。在少数肺栓塞病例中，栓子的起源无法检测到。生前正确诊断的比例较低，在所有经病理解剖证实的栓塞中，只有不超过11%至25%在生前得到了正确诊断。在致命性肺栓塞中，正确的临床诊断率为三分之一。在核医学研究中，根据临床怀疑或深静脉血栓形成的诊断，通过灌注/通气或吸入闪烁扫描来寻找肺栓塞。深静脉血栓形成患者中有38%至57.9%显示有肺栓塞。在所有肺栓塞中，80%检测到多个灌注缺损（2至9个灌注缺损），病变在两肺均匀分布。小腿静脉血栓形成中肺栓塞的发生率为46%，腿部静脉血栓形成中为67%，若累及盆腔静脉则达到77%。值得注意的是，所有肺栓塞中的大多数（46.3%至100%）没有临床症状。了解深静脉血栓形成患者中肺栓塞的高发生率有助于提高肺栓塞的诊断。对于肺栓塞的诊断过程，急性深静脉血栓形成的存在会增加预测试概率（患病率超过50%）。根据贝叶斯定理，肺栓塞的每项阳性检测将获得非常高的测试后概率。
