Adverse events
Thrombus progression or recurrence occurred in 34.5% (n=10) of patients; 40.9% (n=9) in those that received CDT and 14.3% (n=1) in those that received “on-table” tPA. The median time to thrombus progression or recurrence was 0.5 months (range 0.1-14 months) noted on follow up imaging. Minor bleeding complications were noted in 10.3% (n=3) of patients with 3.4% (n=1) experiencing a major bleeding episode following their interventional procedure. The minor bleeding events were minor oozing from venous access sites, epistaxis, and the development of a large (8.2 cm) popliteal hematoma that did not require intervention beyond temporary cessation of anticoagulation and tPA. The major bleeding episode occurred in a neonate who had a large drop in hemoglobin (decrease of 9.9 g/dL) requiring multiple transfusions. While there was no bleeding source identified, this was counted as a major bleeding event due to the large drop in hemoglobin requiring multiple blood transfusions. Three of the bleeding events (including the major bleed) occurred in the patients in the CDT group, with a frequency of 13.6%; one minor bleeding episode occurred in the patients that received “on-table” tPA, a frequency of 14.3%. The median drop in hemoglobin following the procedure was 2.3 g/dL from the pre-procedural blood count; 24.1% of patients (n=7) required a blood transfusion for an acute decline in hemoglobin following the procedure. As the use of interventional devices may result in a decline in measured hemoglobin due to intra-procedural red blood cell depletion (e.g. Indigo thrombectomy, Angiojet thrombolysis and thrombectomy), post-procedural drops in hemoglobin were not counted as bleeding events unless a bleeding event was noted via physical examination or imaging. The median decline in platelet count was 50,000 cells/dL from pre-procedural labs. There were no noted cases of PE following a thrombolysis procedure.
Though our center did not use standardized PTS scoring scales in follow up appointments, 17.2% (n=5) of patients exhibited symptoms of PTS at follow up hematology outpatient visits. This represents 18.2% (n=4) of the CDT and 14.3% (n=1) of the “on-table” groups. These symptoms included lower extremity pain (10.3%, n=3), swelling (10.3%, n=3), and redness/discoloration (3.4%, n=1). The median time from diagnosis/intervention to the development of PTS symptoms was 15.3 months, with a range of 7 to 22.3 months. One patient in the cohort died, though was unrelated to thrombolysis or anticoagulation (died of complications of sepsis without bleeding symptoms noted; he was on anticoagulation for continued therapy of his thrombosis during the hospitalization).