Fast versus ultra-slow thrombolytic infusion regimens in patients with obstructive mechanical prosthetic valve thrombosis: a pilot randomized clinical trial

Background Thrombolysis is an alternative to surgery for mechanical prosthetic valve thrombosis (MPVT). Randomized clinical trials have yet to test safety and efficacy of a proposed ultraslow thrombolytic infusion regimen. Methods and Results This single-center, open-label, pilot randomized clinical trial randomized adult patients with acute obstructive MPVT to an ultraslow thrombolytic regimen (25 mg of recombinant tissue-type plasminogen activator [rtPA] infused in 25h) and a fast thrombolytic regimen (50 mg of rtPA infused in 6h). If thrombolysis failed, a repeated dose of 25 mg of rtPA for 6h was administered in both groups up to a cumulative dose of 150 mg or the occurrence of a complication. Primary outcome was a complete MPVT resolution (>75% fall in the obstructive gradient by transthoracic echocardiography, <10° limitation in opening and closing valve motion angles by fluoroscopy, and symptom improvement). Key safety outcome was a BARC type III or V major bleeding. Overall, 120 patients, including 63 (52.5%) women, at a mean age of 36.3±15.3 years, were randomized. Complete thrombolysis success was achieved in 51 patients (85.0%) in the ultraslow-regimen group and 47 patients (78.3%) in the fast-regimen group (OR, 1.58; 95% CI, 0.25 to 1.63; P = 0.34). One case of transient ischemic attack and 3 cases of intracranial hemorrhage (absolute risk difference, −12.5%; 95% CI, −23.1% to −1.0%; P = 0.04). were observed only in the fast-regimen group. Conclusions The ultraslow thrombolytic regimen conferred a high thrombosis resolution rate without major complications. Such findings should be replicated in more adequately powered trials (IRCT20181022041406N2).

Successful Low-Dose tPA for Mechanical Mitral Valve Thrombosis in a Patient with Postinfarction Contained Left Ventricular Free Wall Rupture

Prosthetic valve thrombosis is a potentially life-threatening complication diagnosed by a combination of clinical features and imaging modalities, but the optimal management in high bleeding risk patients remains controversial. Current treatment options for prosthetic valve thrombosis included surgery, thrombolytic therapy, and anticoagulation. We present a very unusual case of a patient with a recent ST-elevation myocardial infarction complicated by contained left ventricle free wall rupture and mechanical mitral valve thrombosis. Deemed a high surgical risk candidate, low-dose tissue plasminogen activator was used despite significant bleeding risk from contained left ventricle free wall rupture, which resulted in resolution of the thrombus. To the best of our knowledge, this is the first report of successful thrombolytic therapy for prosthetic mechanical mitral valve thrombosis in a patient with recent postmyocardial infarction contained left ventricular free wall rupture.

RESULT OF SLOW INFUSION OF STREPTOKINASE THERAPY IN LEFT SIDED PROSTHETIC VALVE THROMBOTIC OCCLUSION- A CASE SERIES FROM A TERTIARY CARE HOSPITAL IN EASTERN INDIA

Prosthetic valve thrombosis (PVT) is a life threatening complication seen after heart valve replacement and is associated with high mortality and morbidity. Surgical approach or brinolysis and heparin therapy are considered as treatments of choice according to the clinical status of the patient. Thrombolytic therapy has been tried in cases with acute prosthetic valve thrombosis as an alternative to emergency operation with variable results. But fear of peripheral embolism has limited its use in left-sided valve occlusions. The incidence of complications decreases with low dose and slow infusion of brinolytic therapy. In this study we are presenting our experience of thrombolytic therapy with streptokinase in 40 patients who had presented with acute or subacute left-sided prosthetic valve thrombosis. In this study the mean age was 40.9 years (SD-11.2, range-19 to 64 year) with majority (77.5%) were below 50 year of age. Duration of valve replacement was 2.95 ± 1.74 years (1 to 7 years). Average time of presentation since onset of symptoms was 4.75 ± 2.77 days (1 to 12 days). Majority was presented with NYHA class IV symptoms (22/40) and 50% patients presented with cardiogenic shock. 85% patients had atrial brillation and the anticoagulation status was inadequate in 62.5% cases. Overall aortic valve involvement was 37.5% (15 patients) and mitral valve involvement was 62.5% (25 patients). Average mean gradient for aortic valve was 64.5 ±4.2 mm of Hg and that in case of mitral valve was 23.4±3.7 mm of Hg. Duration of thrombolytic therapy was individualized. Average total dose of streptokinase per patient was 25,25000 ± 8,69350 U (ranging from 20,00000 to 50,00000 U) with majority (28/40) had received a total 20,00000U of streptokinase. Patients were re-evaluated after thrombolysis with clinical, echocardiographic, and cine-uoroscopic evaluation. Total complications (both major and minor bleeding) occurred in 8 patients. Most of them were minor like injection site hematoma, gum bleeding transient GI bleed (hematemesis), hemoptysis and those were resolved spontaneously with conservative management/observational care. Thrombolysis was unsuccessful in 2 patients and death due to massive hemorrhagic CVA occurred in 2 patients. Overall success rate was 90% (36/40). In conclusion, the present study demonstrates the feasibility of thrombolytic therapy for left-sided prosthetic valve occlusion.

Mechanical Pulmonary Valve Thrombosis: Recurrence and Response to Thrombolytic Therapy

Prosthetic valve thrombosis (PVT) is a serious complication in the left-sided heart valve. However, in the right-side position, this complication may be completely asymptomatic or accompanied by only a few symptoms. Research on the prevalence of thrombosis in right-sided valves is still insufficient. We sought to retrospectively report our center’s experience concerning PVT and its management outcomes.

What Factors Should Be Considered to Improve Outcome of Mechanical Mitral Valve Replacement in Children?

Objective: To identify risk factors for pediatric mechanical mitral valve replacement (mMVR) to improve management in this challenging population. Methods: From 1993 to 2019, 93 children underwent 119 mMVR operations (median age, 8.8 years [interquartile range [IQR]: 2.1-13.3], 54.6% females) at our institution. Twenty-six (21.8%) patients underwent mMVR at ≤2 years and 93 (78.2%) patients underwent mMVR at >2 years. Median follow-up duration was 7.6 years [IQR: 3.2-12.4]. Results: Early mortality was 9.7%, but decreased with time and was 0% in the most recent era (13.9% from 1993 to 2000, 7.3% from 2001 to 2010, 0% from 2011 to 2019, P = .04). It was higher in patients ≤2 years compared to patients >2 years (26.9% vs 2.2%, P < .01). On multivariable analysis for mitral valve reoperation, valve size <23 mm was significant with a hazard ratio of 5.38 (4.87-19.47, P = .01);. Perioperative stroke occurred in 1% and permanent pacemaker was necessary in 12%. Freedom from mitral valve reoperation was higher in patients >2 years and those with a prosthesis ≥23 mm. Median time to reoperation was 7 years (IQR: 4.5-9.1) in patients >2 years and 3.5 years (IQR: 0.6-7.1) in patients ≤2 years ( P = .0511), but was similar between prosthesis sizes ( P = .6). During follow-up period (median 7.6 years [IQR: 3.2-12.4], stroke occurred in 10%, prosthetic valve thrombosis requiring reoperation in 4%, endocarditis in 3%, and bleeding in 1%. Conclusion: Early and late outcomes of mMVR in children are improved when performed at age >2 years and with prosthesis size ≥23 mm. These factors should be considered in the timing of mMVR.