Treatment of prosthetic tricuspid valve thrombosis with low-dose tissue plasminogen activator

Thrombosis of bileaflet tricuspid valve prosthesis: clinical spectrum and the role of nonsurgical treatment

BACKGROUND

Thrombosis of a mechanical tricuspid valve prosthesis is a potentially hazardous event. This study aimed to explore the incidence and the clinical presentation of tricuspid valve thrombosis occurring in bileaflet valves and to evaluate the diagnostic and the therapeutic approach.

METHODS AND RESULTS

Tricuspid valve thrombosis was sought in 22 late survivors with the CarboMedics valve in a follow-up period of 36.0 +/- 20.8 months. Limited leaflet motion and/or a visible thrombus were considered diagnostic of valve thrombosis. Eight episodes of tricuspid valve thrombosis were diagnosed among 5 patients (12.1 episodes per 100 patient-years). Anticoagulation was inadequate in 3 patients and fair in 2. Florid right heart failure occurred in 3 episodes. Common physical findings included increased jugular venous pulse (5 patients), diastolic tricuspid murmur (4 patients), and peripheral edema (4 patients). The diagnosis was suspected in all clinically and by transthoracic echocardiography and confirmed by fluoroscopy and/or transesophageal echocardiography. In 4 patients, both leaflets were involved. No thrombi were visualized. Three patients received thrombolytic therapy in 4 episodes (complete success in 3, partial success in 1) without hemorrhagic or embolic complications. One patient responded to aggressive anticoagulant therapy. One patient required an emergent repeat surgery. In 1 patient, valve thrombosis recurred thrice.

CONCLUSIONS

In patients with fair or poor anticoagulation, a bileaflet valve in the tricuspid position is associated with a high incidence of valve thrombosis. Hinge entrapment requires only a small amount of thrombotic material. Valve thrombosis may be asymptomatic. Involvement of both leaflets is usually required to produce symptoms. A nonsurgical approach (thrombolysis or intensified anticoagulation) is usually successful. Patients should be instructed about heralding signs of valve thrombosis.

Recombinant tissue type plasminogen activator treatment of thrombosed mitral valve prosthesis during pregnancy

PURPOSE

Prosthetic heart valve thrombosis occurring during pregnancy is a life-threatening complication. Surgical treatment requires clot removal under cardiopulmonary bypass (CPB) and carries a high mortality. We describe the successful use of thrombolytic therapy for recurrent thrombosed valve prosthesis in a pregnant patient.

CLINICAL FEATURES

A 32-yr-old patient whose pregnancy was complicated by two episodes of a thrombosed St Jude mitral prosthesis is reported. The first episode occurred at 20 wk of pregnancy during the change of oral anticoagulant therapy (acenocoumarol 4 mg a day) to sc heparin. As the patient was in cardiogenic shock, the valve thrombus was treated by clot removal under CPB., with a cross clamp time of 32 min, a perfusion pressure above 70 mmHG. There was no fetal cardiac rhythm during CPB which lasted < 45 min. The second episode occurred at the 28th gestational week in a patient in cardiogenic shock and because reoperation was thought to carry too high a risk, the thrombus was successfully treated with 50 mg recombinant tissue plasminogen activators (rtPA) i.v. Following this, the course of pregnancy was uneventful and carried to term and the patient delivered vaginally. Pain relief was achieved with intravenous patient-controlled analgesia with alfentanil (bolus 100 mug; lock out = five minutes). Although rtPA has been used before, this is the first report in which pregnancy was carried to term and standard vaginal delivery performed.

CONCLUSION

This case provides evidence for the efficacy and relative safety of rtPA as thrombolytic therapy in the treatment of haemodynamically compromised valve heart thrombosis in pregnancy.

Prosthetic valve obstruction: thrombolysis versus operation

An acute obstruction is a life-threatening complication of mechanical valve prostheses, and is caused by the formation of fresh clot or fibrous tissue overgrowth, or both. Accurate selection of the most appropriate treatment for a particular patient is mandatory. From January 1991 to July 1992, 28 cases of prosthetic thrombosis were managed. Twenty patients underwent surgical treatment, with one operative death, and 8 patients were treated with thrombolysis using recombinant tissue-type plasminogen activator (rt-PA). The criteria for using thrombolysis were (1) the recent onset of symptoms, (2) transesophageal echocardiographic evidence of clots on the valve or cardiac chambers, and (3) preserved disc excursions. All patients who underwent thrombolysis had mechanical valves (two bileaflets, four tilting discs, and two ball valves); seven valves were in the mitral position and one was in the aortic. Symptoms of obstruction consisted of cardiac failure in 6 cases or thromboembolism in 5, or both. The mean interval between the onset of symptoms and the initiation of thrombolysis was 81 +/- 65 hours. After infusion of the rt-PA, normal valve function was restored in all patients, as documented by transesophageal echocardiography. No deaths or neurologic complications occurred; there was one episode of minor peripheral embolism. Thrombolysis using rt-PA may be the appropriate treatment in patients with primary thrombosis of mechanical valves, thereby avoiding the operation-related risks.

Tricuspid valve replacement with the St. Jude Medical valve

A study was conducted on 20 patients who underwent tricuspid valve replacement (TVR) with the St. Jude Medical (SJM) valve. Isolated TVR was performed on 9 patients, and additional mitral, or mitral and aortic valve replacements were performed on 11 patients. Four patients (20%) died in the early postoperative period, but there were no deaths related to the SJM valve in the tricuspid position. The mean follow-up period of the 16 survivors was 74.4 months, and there have been no deaths during the follow-up period. The postoperative actuarial survival rate was 80%, 10 years after surgery. Three patients, representing 0.25%/patient-months, developed valve thrombosis, the valve thrombosis-free rate being 72.8%, 10 years after surgery, while entrapment of a leaflet by endothelial pannus was found in one patient, representing 0.08%/patient-months. Thus, the incidence of all prosthetic valve-related complications was 0.34%/patient-months, and the postoperative complication-free rate was 65.3%, 10 years after surgery. The medium-term follow-up study of TVR with the SJM valve revealed no prosthetic valve-related deaths and a relatively low incidence of prosthetic valve-related complications. However, as with other mechanical valves, valve thrombosis was a major risk posed by the SJM valve in the tricuspid position.

Thrombolytic treatment for massive thrombosis of prosthetic cardiac valves

OBJECTIVE

To present the efficacy of thrombolytic treatment in place of emergency surgery in massive thrombosis of prosthetic cardiac valves (TPCV), and to set out the diagnostic criteria and the patients' evolution.

DESIGN

Retrospective study.

SETTING

Coronary Care Unit of a Spanish reference hospital.

PATIENTS

7 patients admitted into the ICU with 10 episodes of TPCV and with advanced functional class.

INTERVENTIONS

The diagnosis of TPCV was arrived at through clinical data and was confirmed by Doppler-echocardiography before treatment. Thrombolytic treatment (streptokinase, urokinase or rt-PA) was used. The analysis of paired samples between the data before and after treatment was used.

MEASUREMENTS AND RESULTS

All the patients underwent an improvement in their clinical condition. A reduction of sPAP and in the mean transprosthetic gradient and an increase in the effective valvular area was achieved. Four patients needed surgical intervention during their follow-up. No case required emergency surgery. One patient died after surgery and the other 6 patients are alive after follow-up of 6-33 months. With the fibrinolytic treatment hemorrhagic complications were always controlled. None of the treated patients presented embolic complications.

CONCLUSIONS

Fibrinolytic treatment is the recommended initial treatment in cases of massive TPCV. When fibrinolysis is only partially successful, reoperation can be performed at lower risk. Doppler echocardiography is fundamental in the diagnosis of TPCV and in monitoring the response to fibrinolytic treatment.

Combined thrombolytic therapy for prosthetic mitral valve thrombosis

Prosthetic valve thrombosis is associated with high mortality. The treatment of choice remains operation. This is a case report of the successful combination therapy of tissue plasminogen activator and urokinase for an isolated thrombosed prosthetic mitral valve in a postpartum patient in whom operation was thought to carry an unacceptable risk. Combined thrombolytic therapy or therapy with a single agent with a long half-life and a prolonged infusion time is suggested as an emergent treatment option for prosthetic mitral valve thrombosis.

Use of transesophageal echocardiography during thrombolysis with tissue plasminogen activator of a thrombosed prosthetic mitral valve

Inadequate anticoagulation in patients with mechanical prosthetic heart valves can result in a significant incidence of thromboembolic complications. An even more life-threatening complication is massive thrombosis of the valve itself. Thrombolytic therapy was given to a moribund 22-year-old woman with intractable heart failure caused by a thrombosed St. Jude prosthetic mitral valve (St. Jude Medical, Inc., St. Paul, Minn.). Although this form of therapy has been used before, this is the first report of a case in which transesophageal echocardiography was performed during thrombolytic therapy to continually record successful thrombolysis of the clotted prosthetic valve. Serial imaging during thrombolysis displayed progressive dissolution of the thrombus and progressive improvement in valve function. Transesophageal echocardiography is helpful in the diagnosis of prosthetic valve thrombosis and has the ability to monitor continually the effect of treatment with thrombolysis. Although thrombolytic therapy with recombinant tissue plasminogen activator is effective in treating prosthetic valve thrombosis, it carries a high risk for serious thromboembolic complications and thus should be reserved for critically ill patients who are too sick to undergo immediate surgery.