Catheter-directed thrombolysis for lower limb ischaemia: A retrospective study of treatment outcomes.

INTRODUCTION: Lower limb ischaemia secondary to occlusion of a lower limb artery is a limb-threatening condition that can be effectively treated by catheter-directed thrombolysis (CDT). The purpose of this study was to examine treatment outcomes of CDT both at the time of treatment and ongoing patency up to 12 months following treatment. The secondary aim of the study was to investigate the influence of age of occlusion and treatment duration on success and complication rates. METHOD: A retrospective observational study was performed at a single institution over a 10-year period from 2010 to 2019. Data for patient demographics, vessel occlusion factors and treatment information were obtained and analysed. Patency data were investigated using Kaplan-Meier analyses. RESULTS: A total of 218 limbs in 159 patients were treated during the study period. The aetiology of vessel occlusion was in situ thrombosis or occluded bypass graft in 74.5%. Technical success was achieved in 55.5% with CDT alone and 84.4% by using CDT in combination with adjunctive endovascular procedures (angioplasty or stenting). The overall probability of patency was 0.65 at 3 months and 0.44 at 12 months. The overall rate of major amputation within 30 days of thrombolysis was 8.2%. Thirty-day mortality was 6.3% and was secondary to intracranial haemorrhage in three patients. CONCLUSION: Technical success of CDT was found to be significantly higher when combined with adjunctive endovascular procedures at the time of CDT. Despite an initial moderate technical success, the probability of patency at 12 months was only 44%. The likelihood of bleeding complications and technical and long-term success remain key considerations when selecting patients for CDT.

Role of a quantitative D-dimer assay in determining the need for CT angiography of acute pulmonary embolism.

OBJECTIVE: Our goal was to use the results of a quantitative D-dimer assay to determine the need for pulmonary CT angiography in patients suspected of having acute pulmonary embolism. MATERIALS AND METHODS: From July 2001 to December 2002, 755 patients underwent pulmonary CT angiography for the evaluation of acute pulmonary embolism. A rapid, fully automated quantitative D-dimer assay was obtained in more than half the patients. The electronic medical records of the patients were subsequently reviewed to analyze the negative predictive value of the D-dimer assay in the diagnostic workup of acute pulmonary embolism and to determine the outcome of the patients who had negative findings on both D-dimer assay and pulmonary CT angiography at 3-month follow-up. RESULTS: Of the 755 patients who underwent pulmonary CT angiography, 666 (88.2%) had negative findings, 73 (9.7%) had positive findings, and 16 (2.1%) were indeterminate. A total of 426 patients underwent both pulmonary CT angiography and D-dimer level evaluation, and 84 of these had negative findings (< 0.4 microg/mL) on D-dimer assay. Eighty-two of the 84 patients with negative findings on D-dimer assay had negative findings on pulmonary CT angiography; two were indeterminate and both subsequently had low-probability ventilation-perfusion studies. Among patients with positive D-dimer assays, no one with a level between 0.4 and 1.0 microg/mL had pulmonary CT angiography with findings positive for pulmonary embolism. CONCLUSION: A quantitative D-dimer assay was effective in excluding the need for pulmonary CT angiography and had high negative predictive value when the D-dimer level was less than 1.0 microg/mL.