The role of thrombolysis in the management of left-sided prosthetic valve thrombosis: a study of 85 cases diagnosed by transesophageal echocardiography.

BACKGROUND AND AIM OF THE STUDY

Treatment strategies of prosthetic valve thrombosis (PVT) are controversial. The aim of this study was to compare the efficacy and safety of thrombolysis, surgery and heparin therapy in patients with either obstructive or non-obstructive PVT.

METHODS

Between 1993 and 2000, 85 episodes of PVT were found (82 in the mitral position, three in the aortic) in 59 patients (22 males, 37 females; mean age 53 years; range: 28-80 years) by multiplane transesophageal echocardiography (TEE). Obstructive PVT was defined as restricted leaflet (occluder) motion with increased gradient, even if thrombus was not seen by TEE; non-obstructive PVT was considered as normal leaflet motion, irrespective of the gradients. Thrombolysis was given in 43 episodes (streptokinase, n = 37) by standard dosage protocols, surgery was performed in 20, and i.v. heparin was used in 22. Recurrence rate was calculated in 26 survivors of successful thrombolysis based on six months to six years follow up. Treatment with thrombolysis and heparin was monitored using TEE.

RESULTS

There were 54 cases of obstructive PVT and 31 cases of non-obstructive PVT. Anticoagulation was inadequate in 82% of cases. Thrombolysis was completely successful in 37 cases (86% success rate); in 27 of 32 patients with obstructive PVT (in both cases of aortic location), and in 10 of 11 non-obstructive PVT. Heparin was successful in only nine of 18 non-obstructive PVT, and in none of four obstructive cases. Nine patients died, all with obstructive PVT, and all but one were in NYHA class IV; two were treated by thrombolysis (5% mortality), six by surgery (30% mortality) and one with heparin (5% mortality). Complications of thrombolysis included two strokes and two transient ischemic attack episodes (9%), and bleeding in one case (2%). There were six complications due to heparin treatment: newly developed obstruction in five patients and stroke in one patient. Recurrence was diagnosed in eight episodes in six patients with obstructive PVT after successful thrombolysis (22%); rethrombolysis was successful in four of five cases.

CONCLUSION

Thrombolysis was shown to be superior to surgery in obstructive PVT, especially in NYHA class IV patients. Severe complications of thrombolysis were noted only in the critically ill. As heparin treatment appeared ineffective and unsafe for the treatment of PVT, thrombolysis appeared to be the optimal therapeutic choice in this condition.