Cost-effectiveness of magnetic resonance imaging for diagnosing recurrent ipsilateral deep vein thrombosis

The History of Diagnosing Venous Thromboembolism

An accurate and prompt diagnosis of deep vein thrombosis and/or pulmonary embolism is important to prevent serious complications and mortality. Because the clinical presentation of venous thromboembolism (VTE) is often nonspecific, objective testing by means of radiological imaging is required to confirm the diagnosis. Historically, a diagnosis of VTE involved invasive imaging techniques like contrast venography or conventional pulmonary angiography. Technological developments toward more accurate and less invasive diagnostics have driven the implementation of a variety of newer technologies over the past decades, as well as the derivation and validation of clinical decision rules (CDRs) that can be used to rule out VTE in combination with D-dimer blood tests. In this narrative review, we provide a historical overview of the most notable developments in the imaging techniques and CDRs for VTE diagnosis.

Use of Magnetic Resonance Direct Thrombus Imaging for the Diagnostic Management of Suspected Thrombosis in Routine Clinical Practice

Background  The noninvasive magnetic resonance direct thrombus imaging (MRDTI) technique can be used to diagnose acute deep vein thrombosis (DVT), without the use of intravenous contrast. MRDTI holds the potential to differentiate between acute and chronic DVT and could be helpful when diagnosing thrombosis is challenging. Objectives  Our objective was to evaluate the application of MRDTI in clinical practice, including the frequency and indications of MRDTI scans performed in practice-based conditions, results, impact on treatment decisions, and associated patient outcomes. Methods  A retrospective study was performed at the Leiden University Medical Center, the Netherlands. MRDTI scans performed since its implementation in patients aged ≥18 years as part of clinical practice for the diagnostic management of suspected thrombosis were evaluated. Results  Between October 2015 and September 2023, 36 patients had undergone MRDTI for the diagnostic evaluation of thrombosis. MRDTI application increased since 2019 (five-eight scans per year). The most common indication was to differentiate between acute and chronic thrombosis, mainly for suspected recurrent ipsilateral DVT after inconclusive compression ultrasonography. In over a third of patients, acute thrombosis was confirmed by MRDTI. MRDTI results determined treatment decisions in all except two patients. One patient had symptomatic thrombosis of the lower extremity within 3 months after an MRDTI of the upper extremity without signs of acute thrombosis (1/23; 4.3%, 95% confidence interval: 0.77-21). Conclusion  Over the past 4 years, MRDTI has been used increasingly in our hospital. MRDTI results guided treatment decisions, which confirms the clinical impact and feasibility of its application in daily practice.

Cost-Effectiveness of Performing Reference Ultrasonography in Patients with Deep Vein Thrombosis

BACKGROUND

 The diagnosis of recurrent ipsilateral deep vein thrombosis (DVT) with compression ultrasonography (CUS) may be hindered by residual intravascular obstruction after previous DVT. A reference CUS, an additional ultrasound performed at anticoagulant discontinuation, may improve the diagnostic work-up of suspected recurrent ipsilateral DVT by providing baseline images for future comparison.

OBJECTIVES

 To evaluate the cost-effectiveness of routinely performing reference CUS in DVT patients.

METHODS

 Patient-level data (n = 96) from a prospective management study (Theia study; NCT02262052) and claims data were used in a decision analytic model to compare 12 scenarios for diagnostic management of suspected recurrent ipsilateral DVT. Estimated health care costs and mortality due to misdiagnosis, recurrent venous thromboembolism, and bleeding during the first year of follow-up after presentation with suspected recurrence were compared.

RESULTS

 All six scenarios including reference CUS had higher estimated 1-year costs (€1,763-€1,913) than the six without reference CUS (€1,192-€1,474). Costs were higher because reference CUS results often remained unused, as 20% of patients (according to claims data) would return with suspected recurrent DVT. Estimated mortality was comparable in scenarios with (14.8-17.9 per 10,000 patients) and without reference CUS (14.0-18.5 per 10,000). None of the four potentially most desirable scenarios included reference CUS.

CONCLUSION

 One-year health care costs of diagnostic strategies for suspected recurrent ipsilateral DVT including reference CUS are higher compared to strategies without reference CUS, without mortality benefit. These results can inform policy-makers regarding use of health care resources during follow-up after DVT. From a cost-effectiveness perspective, the findings do not support the routine application of reference CUS.