Management
The heart team evaluated and reviewed the images obtained via MDCT,
objectively elected to pursue thrombolytic therapy, tissue plasminogen
activator (tPA) infusion was started. The patient received 10 mg IV
bolus followed by 90 mg over approximately 2 hours. A repeat aortic
valve fluoroscopy demonstrated restricted valve motion [video 3]. A
second round of tPA was administered at the same dosage. A limited
echocardiogram showed improved gradient across the aortic valve with
peak gradient of 16 mmHg and mean gradient of 10 mmHg and no
regurgitation. The heart team decision was made to repeat tPA infusion
at a lower dose. The patient received 1 mg/h of tissue plasminogen
activator infusion for 25 hours. A repeat TTE revealed more improvement
of transaortic velocity/gradient with peak gradient 15 mmHg and mean
gradient of 8 mmHg but with a small thrombus still present. Patient
symptoms had resolved. A valve fluoroscopy obtained a couple of days
later still showed no significant movement of one of the mechanical
aortic valve leaflets [Video 4]. The patient received a fourth dose
of low dose tPA infusion as the previous described above. Follow up MDCT
obtained three days after the fourth tPA infusion, revealed resolution
of the thrombus with normal leaflets excursion [Video 5]. There were
no hemorrhagic complications. IV heparin used between tPA treatment was
resumed after the fourth dose as a bridge to warfarin until achievement
of therapeutic INR.