Background: Venous thromboembolism is a disorder including both deep venous thrombosis, the most common form of venous thromboembolism and pulmonary thromboembolism which is the most life-threatening manifestation of venous thromboembolism. The imaging evaluation of the venous thromboembolism ideally should include both deep veins of lower limbs and pulmonary arterial system¹.Recent advances in the imaging techniques have made possible to evaluate the spectrum of imaging findings in venous thromboembolism, the most common and the evolving one being CT pulmonary angiography with indirect venography.

Objectives: 1.To calculate the proportion of patients having DVT as diagnosed using indirect venography in clinically suspected cases of pulmonary embolism. 2.To determine the proportion of patients with venous thromboembolism, i.e., concomitant DVT and PE, DVT alone and pulmonary embolism alone.

Materials and Methods: Patients who were clinically suspected to have pulmonary embolism underwent CT pulmonary angiography along with indirect venography. Clinical symptoms, signs and echo findings of these patients were collected using pre-prepared proforma, and the prevalence was calculated. Also, the prevalence of venous thromboembolism (combined pulmonary embolism and deep venous thrombosis), pulmonary embolism alone and deep venous thrombosis alone were evaluated using with SPSS, version 22.

Results: The study population comprised of 66 patients; The prevalence of venous thromboembolism in our study population was 37.87%, i.e., 25 patients with venous thromboembolism out of 66 suspected cases of pulmonary embolism. Prevalence of pulmonary embolism was 19(28.78%), and deep venous thrombosis was 19(28.78%). Out of the 25 patients with venous thromboembolism, 13 (19.7% of all patients and 52% of patients with venous thromboembolism) had both pulmonary embolism and deep venous thrombosis. Isolated pulmonary embolism and isolated deep venous thrombosis was seen in 6 (9.09% of all patients and 24% of patients with venous thromboembolism) patients each.

Conclusion: We conclude that, the proportion of patients with venous thromboembolism was 37.8 %; with concomitant PE and DVT in 19.7 % patients, isolated DVT and isolated PE each in 9.0 % patients. Our study also showed that there was isolated occurrence of pulmonary embolism and isolated deep venous thrombosis which emphasizes the need to screen for DVT during the evaluation of any suspected cases of pulmonary embolism.

Keywords: VTE: Venous thromboembolism, DVT: Deep venous thrombosis, PE: Pulmonary embolism, CT: Computed Tomography.

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Dr Mathew George

Assistant Professor, Pushpagiri Institute of Medical Sciences & Research Centre, Thiruvalla, Kerala, India