[Prosthetic valve thrombosis: which is the most appropriate initial therapy?]

Management of prosthetic valve thrombosis with unfractionated heparin

BACKGROUND

Prosthetic valve thrombosis (PVT) is a severe and life-threatening complication. Surgery and thrombolytic therapy (TT) carry a high risk, and in several circumstances, optimal anticoagulation with unfractionated heparin (UFH) infusion may be an alternative treatment. This study aimed to assess the results of UFH in patients diagnosed with both obstructive and non-obstructive PVT.

METHODS

This observational retrospective study enrolled patients who had contraindications for TT and surgery underwent UFH therapy.

RESULTS

A total of 136 patients were enrolled [male: 55 (40.4%), mean age: 50.3 ± 14.6 years] in the study. In the successful group, 66 patients (48,5%) showed >75% regression in the thrombus burden without facing death or major non-fatal complications.In the unsuccessful group, 56 had less than a 50% reduction in thrombus load and 14 (10.3%) suffered major complications. The presence of obstruction (27.1% vs. 12.1%; p = 0.028), thrombus area 1.1 cm2 vs. 0.8 cm2; p = 0.005] and the duration of UFH treatment (15.1 vs. 11.8 (days); p = 0.005) were significantly higher in the unsuccessful UFH group.In multivariate regression analyses the presence of obstruction (RR: 3.088, p = 0.020), increased thrombus area (RR: 2.400; p = 0.015), and increased duration of UFH therapy (RR: 1.073 95%, p = 0.012) were identified as independent predictive parameters for a failed UFH therapy.

CONCLUSIONS

This study suggests that UFH therapy may be considered a relatively beneficial treatment strategy for some patients with PVT. The most significant factors affecting success are the obstructive nature and area of the thrombus.

Comparison between surgery and fibrinolytic therapy in prosthetic valve thrombosis: A systematic review and meta-analysis

BACKGROUND

Prosthetic valve thrombosis (PVT) is a rare but life-threatening complication. Surgery and fibrinolytic therapy (FT) are the two main treatment options for PVT. The choice between surgery and FT has always been a matter of debate. Previous studies have shown that although the mortality rate is higher in surgery, complications are less frequent than in FT. We aimed to perform a systematic review and meta-analysis to compare the results of surgery and FT in PVT.

METHODS

A systematic review of the literature was performed through Medline, Embase, Scopus, and Web of Science, encompassing all studies comparing surgery and FT in PVT. The rate of each complication and risk ratio (RR) of complications in surgery and FT were assessed using random-effects models.

RESULTS

Fifteen studies with 1235 patients were included in the meta-analysis. The pooled risk of the mortality was not significantly different between FT and surgery in patients with PVT (pooled RR = 0.78, 95% confidence interval [CI]: 0.38-1.60, I² = 61.4%). The pooled risks of thromboembolic events (pooled RR = 4.70, 95% CI: 1.83-12.07, I² = 49.6%) and major bleeding (pooled RR = 2.45, 95% CI: 1.09-5.50, I² = 41.1%) and PVT recurrence (pooled RR = 2.06 95% CI: 1.29-3.27, I² = 0.0%) were significantly higher in patients who received FT.

CONCLUSION

Surgery may be safer and with fewer complications than FT for PVT treatment. However, randomized clinical trials are needed to determine the proper treatment for PVT.

Loss of engagement in controlling chronic anticoagulation therapy during Covid-19 stringency measures. A single center experience of disproportioned increase of stuck mechanical valves

Stuck valve is a very rare and severe complication that occurs in mechanical valve replacement patients with ineffective anticoagulation. However, with COVID-19 restriction measures, it became challenging to regularly assess INR to make sure it falls within the target therapeutic range to prevent this complication. We present a series of 10 patients who either underwent transthoracic echocardiography for a suspected stuck valve or were seen at the outpatient valve clinic with the residual consequences of a stuck valve during the COVID-19 restriction measures in our institute. Stuck prosthetic valves incident has increased significantly during this period, particularly those in the mitral position for which urgent replacement and prolonged hospitalization were necessary. Particularly with the COVID-19 restrictions in place, these cases highlight the need for physicians to be aware of the dramatic increase in the incidence of stuck prosthetic valves in patients on chronic warfarin therapy.

Non-obstructive prosthetic heart valve thrombosis (NOPVT): Really a benign entity?

AIMS

To assess the effectiveness of different treatment strategies in patients with non-obstructive prosthetic valve thrombosis (NOPVT) during hospitalization and long-term follow-up.

METHODS

NOPVT was diagnosed by transesophageal echocardiography. Resolution was defined as the disappearance or reduction of the thrombus under anticoagulation. All cases were first managed with optimization of anticoagulation. At discharge, patients received oral anticoagulation (OAC) alone or OAC and antiplatelet therapy (double treatment). Adverse events were defined as cardiovascular death, recurrence, thromboembolic events or major bleeding.

RESULTS

From 1997 to 2012, 47 patients (mean age: 65years; women: 60%) were diagnosed with NOPVT (mitral valve: 97%). Previous poor anticoagulation control was documented in 66% of patients. Twenty-one patients (45%) were treated with unfractionated heparin (UFH), especially those with thrombus size >10mm (19/21). Optimization of OAC was performed in the remaining patients. Treatment failed in 13 (27.6%) patients, mostly in those who received UFH (10/13), requiring surgery (53.8%) or fibrinolysis (30.7%). Forty-two patients survived and, at discharge, 44% of patients received OAC alone and 56% the double treatment. At follow-up (median 23months; range 0.03-116months), 59.5% of patients presented cardiovascular events, however no differences in outcome were observed with double treatment or OAC alone (p=0.385).

CONCLUSIONS

NOPVT is a high-risk complication, not only during hospitalization but also during follow-up. Optimization of anticoagulation is efficient in most patients except in thrombi ≥10mm treated with UFH. The double treatment does not prevent adverse events or complications during follow-up.

Thrombolytic therapy or surgery for valve prosthesis thrombosis: systematic review and meta-analysis

BACKGROUND

Prosthetic heart valve thrombosis is a life-threatening condition for which treatment has not been evaluated by randomized trials.

OBJECTIVES

To compare surgery with thrombolytic therapy for the treatment of prosthetic valve thrombosis.

METHODS

A comprehensive systematic review was carried out by independent researchers using PubMed, Web of Knowledge, HINARI, LILACS and EMBASE, including papers indexed up to 23 October 2013 with at least 10 patients, evaluating one or both treatment options. Outcomes of interest were death, stroke, bleeding, embolic events and success. Study quality was assessed by the Newcastle-Ottawa Scale (ranges from 0 to 9). Comprehensive Meta Analysis Software was used to pool study results, for publication bias analysis and for meta-regression.

RESULTS

Forty-eight studies were included (2302 patients). No randomized study was identified, and all were observational in design. Study quality varied from 4 to 6 stars using the Newcastle-Ottawa Scale. Mortality for surgery was 18.1% (95%CI, 14.6-22.1; I(2) , 62% [42-75]), while mortality for thrombolytic therapy was 6.6% (95% CI, 4.8-8.9; I(2) , 0% [0-13]). Surgical mortality appeared to increase with NYHA-class, according to meta-regression. Other results related to surgery and thrombolytic therapy, respectively, were: embolic events, 4.6% (2.9-7.3) and 12.8% (10.8-15.2); stroke, 4.3%,(2.7-6.6%) and 5.6%,(4.3-7.4%); success rate, 81.9% (77.2-85.8) and 80.7% (75.6-85.0); bleeding, 4.6% (2.9-7.1) and 6.8% (5.4-8.6); and death or stroke, 19.0% (14.8-24.2) and 11.4% (8.7-14.7).

CONCLUSION

Mortality in patients treated by thrombolytic therapy for valve prosthesis thrombosis is significantly lower than in patients treated surgically. As we cannot yet ascertain whether this difference is due to the treatment alone, more studies are now necessary to further clarify these findings.

Thrombolysis as first choice therapy in prosthetic heart valve thrombosis. A study of 68 patients

BACKGROUND AND OBJECTIVES

Valvular thrombosis is a serious complication in patients with prosthetic heart valves. Traditional treatment is emergency surgery, but thrombolysis provides a non invasive alternative. In this paper we evaluate the efficacy and safety of thrombolysis in prosthetic heart valve thrombosis.

METHODS

Data of 68 patients diagnosed of prosthetic valve thrombosis, treated at the Institute of Cardiology and Cardiovascular Surgery, Havana during a 6-years period were analyzed. They received thrombolysis with a recombinant streptokinase infusion at 250,000 IU in 30 minutes followed by 100,000 IU/hour during 72 hours or less if the thrombosis resolved before. The evaluation was based on clinical and echocardiographic findings.

RESULTS

Affected sites were mitral (50 cases), tricuspid (9), and aortic (9). Mean time of prosthesis implantation was 6.8 years. The presentation form was generally heart failure (NYHA functional class III-IV) in 64 (94.1%) patients. Mean time interval between onset of symptoms and diagnosis was 10.6 days. There was total response to treatment in 58 (85.3%) patients, partial in 4 (5.9%) and failure in 6 (8.8%). Recombinant streptokinase overall dose was 5.1 x 10(6) IU and mean infusion time 50 hours. Major hemorrhagic complications were observed in two patients. Five embolic events occurred during thrombolysis. Four patients died. Rethrombosis was noted in 11 patients; 10 were retreated successfully with thrombolysis.

CONCLUSIONS

Thrombolysis with recombinant streptokinase is efficacious and safe for the treatment of prosthetic heart valve thrombosis. It does not contraindicate surgical treatment if there is no total response, because patient goes to surgery in better hemodynamic conditions with lower risk. Nowadays it can be considered as first-line treatment in all patients with prosthetic heart valve thrombosis regardless of functional class unless specific contraindications exist.

Prosthetic heart valve thrombosis: pathogenesis, diagnosis and management

Thrombosis of a prosthetic valve is one of the most severe complications of cardiac valve replacement. The incidence is 0.5% in the aortic and mitral positions and up to 20% in the tricuspid position. The presenting clinical picture ranges from the absence of symptoms to cardiogenic shock. The traditional treatment of this complication has been emergency surgery, but thrombolysis, which has been available for many years, is being considered as the first line of treatment more and more every day. The pathogenesis, diagnosis and treatment of thrombosis of prosthetic heart valves are reviewed here. Thrombolysis, which has an efficacy of over 80%, is emphasized in this review. Embolic complications associated with this therapeutic approach remain a great concern with rates of 3% to 10%, and some authors reporting rates up to 20%.