Search

Objective: The differences in the clinical findings of patients with acute pulmonary thromboembolism (acute-PTE) and chronic pulmonary thromboembolism (chronic-PTE) were compared, and the association between the clinical findings and prognosis in the two groups was analyzed., Patients: This study included 204 patients with PTE, 139 patients with acute-PTE and 65 patients with chronic-PTE., Results: There were significant differences between acute-PTE and chronic-PTE in the predisposing factors of post operation (19.4 versus 1.5%, p = 0.0003), and electrocardiographic signs such as sinus tachycardia (73.7 versus 50.9 %, p = 0.007), ST-depression (25.3 versus 9.4%, p = 0.03), right ventricular hypertrophy (20.0 versus 47.2%, p = 0.0007), and right axis deviation (3.2 versus 22.6%, p = 0.0003). Thirty-one of the 139 acute-PTE patients died from PTE, as did 17 of the 65 chronic-PTE patients. The prognosis was poor in patients older than 70 years old (p = 0.01), with stroke (p = 0.008), syncope (p = 0.01), shock (p = 0.0006), hypocapnia (PaCO2 < or = 25 torr; p = 0.0006) and an elevation in total pulmonary resistance (TPR >1,000 dyne-sec cm(-5) (p = 0.02)) in acute-PTE, and in those with syncope (p = 0.03), shock (p = 0.008), and right ventricular hypertrophy on electrocardiogram (p = 0.03) in chronic-PTE., Conclusion: The results of this study indicate a relationship between the clinical features of patients with acute-PTE and chronic-PTE, and the predictors of in-hospital mortality.

Pulmonary thromboembolism (PTE) is considered an uncommon disease in Japan and there are not any reported prospective studies on the incidence of PTE in Japan. The objective of the present study was to determine the number of patients with PTE per year in a prospective study using a questionnaire. Letters were sent to clinical departments in university schools of medicine or medical colleges, and to hospitals with more than 100 beds. The diagnosis of PTE was to be confirmed by (1) pulmonary artery stenosis or occlusion on pulmonary angiography, (2) mismatch of pulmonary perfusion scintigraphy and pulmonary ventilation scintigraphy, (3) changes on pulmonary perfusion scintigraphy performed twice, or (4) autopsy. The questionnaire elicited 2,341 replies (the withdrawal rate was 40.7%). In 231 hospitals, 237 patients were diagnosed definitely during the study period of 2 months from 1 August to 30 September 1996. From this it was estimated that there are 3,492 (95% confidence interval: 3,280-3,703) patients with PTE per year, which implies that the incidence is 28 persons per 1,000,000 people per year, confirming that PTE is rare in Japan.

The incidence of pulmonary thromboembolism (PTE) is lower in Japanese than in Caucasians. The basis for the different incidence has not been clarified. A poor anticoagulant response to activated protein C based on a single point mutation of the factor V gene (Arg506Gln) was found to be a pathogenetic factor for venous thrombosis and PTE in North America and Europe. We investigated whether the Arg506Gln mutation of factor V is responsible for the occurrence of PTE among Japanese. We analyzed genomic DNA prepared from fresh peripheral blood of 25 patients with PTE of unknown etiology (12 of acute type and 13 of chronic type) and that of 110 controls without respiratory or circulatory disorders. To detect the Arg506Gln mutation, 267 bp DNA fragments of the factor V gene including the Arg506Gln region were amplified by PCR, digested by MnlI and electrophoresed. After digestion of PCR products with MnlI, DNA fragments of 163 bp length, but not DNA fragments of 200 bp length, were identified in all samples, indicating the absence of the Arg506Gln mutation in the patients with PTE and control subjects. These results suggest that the Arg506Gln mutation is absent or very rare and not an important pathogenetic factor for PTE in Japanese.