Wells' prediction rules for pulmonary embolism: valid in all clinical subgroups?

Pulmonary embolism is major cause of hospital death. Clinical prediction rules such as Wells' prediction rules can help in selection of at-risk patients who need further testing for pulmonary embolism. We evaluated the usefulness of such criteria for detection of patients with diagnosed pulmonary embolism. Patients enrolled in National Research Institute of Tuberculosis and Lung Disease (NRITLD) deep venous thrombosis (DVT) registry were evaluated and those with objective data about presence or absence of pulmonary embolism were selected for this study. Diagnosis of pulmonary embolism was based on computed tomography pulmonary angiography (CTPA). We calculated the embolic burden in those with CTPA-confirmed pulmonary embolism. Eighty-six patients entered the study (58 males, 28 females, mean age = 54.39 ± 1.74 years). Fifty-four cases had coexisting pulmonary embolism (embolic burden score: 10.77 ± 1.181). Embolic burden score was correlated to presence of massive pulmonary embolism (Pearson rho: 0.43, P = 0.002). There was no association between Wells' pulmonary embolism score and the occurrence of pulmonary embolism (Spearman's rho: 0.085, P = 0.51). Dividing the patients into two, or three, risk groups according to Wells' model did not reveal an association with occurrence of pulmonary embolism either (P = 0.99 and P = 0.261, respectively). Tachycardia and hemoptysis were the only parameters from the Wells' pulmonary embolism score correlated to presence of pulmonary embolism (Spearman's rho: 0.373, P < 0.000 and Spearman's rho: 0.297, P = 0.005, correspondingly). Wells' pulmonary embolism score could not predict the occurrence of pulmonary embolism in DVT patients suspected of having coexisting pulmonary embolism. Until further studies shed light on this patient subset, overreliance on Wells' prediction rules as the solo decision making tool should be cautioned.

Dexter versus sinister deep vein thrombosis: which is the more sinister? Findings from the NRITLD DVT registry.

Deep vein thrombosis (DVT) is a major health problem. Despite the wealth of studies on its epidemiology, few have described the thrombus sidedness and particularly the association of thrombus sidedness with clinical presentation and subsequent complications. This article reviews current knowledge regarding this topic and in light of recent data from a large prospective study. This is the first report from the prospective National Research Institute of Tuberculosis and Lung Disease DVT registry. Patients with ultrasound-confirmed symptomatic DVT were enrolled, and thrombus sidedness was investigated in each case. Computed tomography pulmonary angiography was used to diagnose coexisting pulmonary embolism (PE) in DVT patients with suggestive symptoms. Embolic burden score was calculated for those with PE. From the total of 100 patients, 45 had left-sided DVT, 41 had right-sided DVT, and 14 had bilateral DVT. Presenting symptoms and comorbidities were comparable, except for cancer, which was more common in those with right-sided involvement (either right-sided or bilateral DVT; P = 0.004). Compared with those with left-sided DVT, PE happened more frequently in right-sided DVT patients. Right-sided DVT patients also had a higher rate of massive PE ( P = 0.03) and a greater mean embolic burden (13.32 ± 1.63 versus 6.05 ± 1.06; P = 0.001). These findings support raised awareness for global reconsideration of the assumption of complete identicalness of right-sided and left-sided DVT. Although future studies are needed to better elucidate epidemiological and prognostic differences based on the thrombus sidedness, our preliminary findings suggest that the two are not completely identical and right-sided DVT might be more ominous.