Impact of Left Atrial Hemodynamics on the Development of Pulmonary Vein Stump Thrombus: Results of Early and Late Postoperative Studies.

[PURPOSE] Pulmonary vein stump thrombus (PVST) is a relatively common complication after left upper lobectomy that can cause vital organ embolism. We previously found that patients with PVST on postoperative day 7 show risky hemodynamic features around the pulmonary vein stump on 4-dimensional (4D) flow magnetic resonance imaging (MRI), which may contribute to thrombus development. However, it remains unclear whether such hemodynamics persist later.

[METHODS] Eleven patients who underwent left upper lobectomy for lung cancer received 4D flow MRI on postoperative day 7 and again after over 3 months. Hemodynamic parameters were used to classify each case as risky or non-risky for PVST.

[RESULTS] According to a total of 24 examinations in 11 patients, 7 were classified as risky and 17 as non-risky. PVST developed in 6 patients during various postoperative phases, and all PVST cases developed under the risky conditions. Furthermore, PVST did not develop under non-risky conditions, suggesting that our risk assessment is valid as a predictive marker for PVST.

[CONCLUSION] Our results suggest that late postoperative hemodynamic assessments, as well as early postoperative assessments, are useful for identifying patients at high risk of PVST. A late postoperative hemodynamic assessment may contribute to determining when to discontinue anticoagulants.