LEFT ATRIAL THROMBI DESPITE ANTICOAGULANT AND ANTIPLATELET THERAPY

To investigate risk tactors for embolization in patients with echocard iographically detected left atrial thrombi and to evaluate thrombus de velopment, we examined 29 patients with transesophageal and transthora cic echocardiography at two points during a follow-up of 18 months. We compared patients with a history of possible arterial embolization (n = 13) with those without (n = 16) in regard to age, gender, left atri al dilatation, localization of the thrombus in the left atrial cavity, spontaneous echo contrast, and atrial fibrillation. Eight patients we re treated with aspirin, 20 with phenprocoumon. Only left atrial spont aneous contrast was associated with thrombembolism (10/15 patients wit h spontaneous contrast experienced arterial embolism; p = 0.038). In s ix patients arterial embolism occurred after thrombus detection (14% p er patient per year). Four of these patients were treated with phenpro coumon, two with aspirin. At reexamination, one thrombus was detected in the patient without anticoagulant treatment and one thrombus was de tected in the 8 patients treated with aspirin (13%), compared with ten thrombi detected in the 20 patients (50%) treated with phenprocoumon (p = NS). In 17 patients no thrombus was seen at reexamination, Since only 2 patients had undergone thrombectomy and 3 experienced arterial embolism during follow-up, thrombi disappeared under medical therapy i n 12 patients. Patients with left atrial thrombi have a high risk of a rterial embolization despite proper anticoagulative or antiplatelet tr eatment. Embolization occurs significantly more often if spontaneous e cho contrast can be visualized. Left atrial thrombi can be reduced in size by the administration of antiplatelet and anticoagulative agents. Detection of left atrial thrombi with transesophageal echocardiograph y identifies this patient population at an increased fisk of embolizat ion