A global perspective on mechanical prosthetic heart valve thrombosis: Diagnostic and therapeutic challenges

Periprocedural Bridging Therapy in Patients With Mechanical Heart Valves

Mechanical heart valves (MHVs) are thrombogenic and require lifelong anticoagulation with vitamin K antagonists (VKAs) such as warfarin. Periprocedural bridging with unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) aims to reduce the risk of thromboembolic events in patients. Currently, there are no definitive class I recommendations for anticoagulation management in patients with MHVs. In this report, we present the case of a 77-year-old female who was perioperatively bridged with enoxaparin and subsequently developed an acute thrombus.

The catastrophic association of prosthetic mitral valve thrombosis and hemorrhagic stroke

Prosthetic valve thrombosis is a serious complication of valve replacement associated with a high mortality rate. Stroke may be the first symptom of prosthetic valve thrombosis. We present the case of a patient who visited the emergency department with symptoms of dysarthria and left hemiparesis. An examination revealed an ischemic stroke with hemorrhagic transformation, stemming from a thrombosis of their mitral valve prosthesis, which progressed to the patient's death. We emphasize the difficulty in the therapeutic and diagnostic management of these patients.

The role of multidetector CT scan in the management of prosthetic aortic valve thrombosis: A case report

Key Clinical Message

In this case report, the utility of MDCT in elucidating the pathophysiology and etiology of prosthetic aortic valve dysfunction allowed us to distinguish thrombosis from pannus as an etiology of prosthetic valve dysfunction. MDCT also guided the success of therapy.

Abstract

The diagnosis and management of prosthetic aortic valve thrombosis (PAVT) is challenging. The accurate diagnosis of this entity and its prompt management is vital to improving the prognosis of PAVT patients. Multidetector CT plays a central role in this effort. We present a case of PAVT in which the use of MDCT was useful in guiding management.

Case report: Mechanical mitral prosthetic valve thrombosis in the context of COVID-19 despite effective anticoagulation

Background

The SARS-CoV2 virus has been an emerging virus since December 2019 and is the cause of a global pandemic whose clinical manifestations extend far beyond respiratory disease.

Case summary

A patient with severe coronavirus disease 2019 respiratory infection, carrying a mechanical mitral valve and under anticoagulation, was admitted to our cardiology department because of a new atrial fibrillation, which turned out to be related to thrombosis of the mitral mechanical valve.

Conclusion

The pro-coagulant effect of the SARS-CoV2 virus does not spare patients at risk of thrombosis, even under effective anticoagulation. In patients with mechanical valves under vitamin K antagonist treatment, there is a high risk of thrombus formation. The treatment is based on thrombolysis by therapeutic anticoagulation, fibrinolysis, or surgery depending on the size, composition of thrombus, and clinical manifestation.

Thrombosis Prevention and Anticoagulation Management in the Pediatric Patient with Congenital Heart Disease

Thrombosis is one of the most frequent complications affecting children with congenital heart disease (CHD). Palliative and reparative cardiac surgeries are some of the main players contributing to the thrombosis risk in this patient population. Additional risk factors related to the CHD itself (e.g., cardiac dysfunction, arrhythmias, and polycythemia in cyanotic cardiac disorders) can contribute to thrombogenicity alone or combined with other factors. Thrombotic complications have been recognized as a significant cause of morbidity and mortality in this patient population. Here, we provide an overview of the pathophysiology and risk factors for thrombosis as well as the indications for and use of different anticoagulation, antiplatelet, and thrombolytic agents. In addition, we describe some of most common thrombotic complications and their management in the pediatric CHD population.

Successful treatment of acute promyelocytic leukemia in a patient with prosthetic heart valves: a case report and review of the literature

BACKGROUND

Although life-threatening hemorrhage is a usual manifestation of acute promyelocytic leukemia (APL), thrombotic events seem to be more common in APL compared to other subtypes of acute leukemia. The treatment and prophylaxis of thrombosis are controversial due to the high risk of bleeding caused by disseminated intravascular coagulation (DIC) and thrombocytopenia. To the best of our knowledge we report the first case of APL in a patient with prosthetic heart valves successfully treated with a combination of all-trans-retinoic acid (ATRA) and arsenic trioxide (ATO). We hope this case report helps clinicians to manage different spectra of coagulopathy in APL successfully.

CASE PRESENTATION

A 38-year-old Asian man presented with diagnosis of APL confirmed by bone marrow biopsy. He was on warfarin due to prosthetic mitral and aortic valves. He was at risk of both hemorrhagic events due to DIC and life-threatening valve thrombosis. Our management regimen included unfractionated heparin adjusted according to the platelet count to prevent both valve thrombosis and bleeding events. The patient tolerated treatment well without any hemorrhagic or thrombotic events, and complete molecular remission was achieved by ATRA and ATO without the need for chemotherapeutic agents.

CONCLUSION

Although this case is exceptional, a precise evaluation may be needed to select the appropriate dose and type of anticoagulant to treat a patient with APL.

Characteristic localization patterns of thrombus on various brands of bileaflet mitral mechanical heart valves as assessed by three-dimensional transesophageal echocardiography and their relationship with thromboembolism

Three-dimensional transesophageal echocardiography (3D-TEE) provides detailed images of prosthetic valve thrombosis (PVT). However, data regarding PVT localization patterns based on 3D-TEE and their association with clinical findings among various bileaflet mitral prosthetic valve brands is lacking. The locations of thrombi were classified into 4 groups according to hinge and annulus involvement based on 3D-TEE: ring-like PVT involving entire mitral annulus (type-1), PVT involving peri-hinge(s) region and extends through some part of the annulus (type-2), PVT involving mitral annulus without involving hinge(s) region (type-3), and PVT involving only (peri)hinge(s) area (type-4). This study was conducted in 265 patients (male: 71, mean age: 46.3 ± 12.7 years) with mitral PVT, including 150 St Jude Medical (SJM), 65 Carbomedics, 29 Medtronic ATS open-pivot, and 21 Sorin bileaflet mechanical valves. There was a significant difference in most common PVT localization patterns between different prosthetic valves (type-1 for Carbomedics and Sorin; type-2 for SJM and type-3 for ATS valves; p < 0.001). Additionally, PVT involving only (peri)hinge region(s) (type-4) was mostly observed in patients with SJM valves (18%). (Peri)hinge(s) area involvement was observed in the majority of study patients (78.1%). In patients who presented with thromboembolism, the most common PVT localization pattern was type-1 (53%). Increased age, low international normalized ratio on admission, PVT with a mobile part > 2 mm, type-1 and type-4 PVT were associated with thromboembolic events. In conclusion, thrombus can be displayed in distinct locations in several types of bileaflet mechanical valves due to different design, hinge and pivot mechanisms, which can be complicated with thromboembolic events.

Mechanical prosthetic valve thrombosis in current era: 5-year follow-up

INTRODUCTION

The incidence of prosthetic valve dysfunction (stuck valve) is variable and is dependent on various factors. There are studies from Indian groups that have emphasized the success of thrombolysis; however, none of them reported a follow-up. This study was designed to emphasize on the follow-up of these patients at midterm.

MATERIAL AND METHODS

The patients of prosthetic valve thrombosis between period of January 2013 and December 2017 were included in this retrospective observational study. Sixty-six patients were admitted with stuck valve during this period. Thrombolysis was preferred modality of treatment. Survivors were followed up with serial echocardiography, which included estimation of left ventricular and valve functions.

RESULTS

Of a total of 66 patients, 59 were of stuck mitral valve and 7 stuck aortic valve. The event happened at a mean of 48.86 ± 48.80 months after index operation of valve replacement using mechanical valve prosthesis. The median age was 40.27 ± 10.8 years with 39 males and 27 females. Thrombolysis was successful in 61 patients with a mortality of 5 (7.57%). During a mean follow-up of 22.7 ± 20.9 months, 42 patients were alive with 14 (22.95%) patients dead and 5 patients lost to follow-up. The average follow-up was 18.7 ± 22.7 months before death.

CONCLUSION

Following good early results after thrombolysis, patients of prosthetic heart valve thrombosis experience high mortality within 2 years of follow-up. These patients require frequent follow-up to avoid early mortality.

Proper Orthogonal Decomposition Analysis of the Flow Downstream of a Dysfunctional Bileaflet Mechanical Aortic Valve

PURPOSE

Aortic valve replacement remains the only viable solution for symptomatic patients with severe aortic valve stenosis. Despite their improved design and long history of successful operation, bileaflet mechanical heart valves are still associated with post-operative complications leading to valve dysfunction. Thus, the flow dynamics can be highly disturbed downstream of the dysfunctional valve.

METHODS

In this in vitro study, the flow dynamics downstream of healthy and dysfunctional bileaflet mechanical heart valves have been investigated using particle image velocimetry measurements. Proper orthogonal decomposition of the velocity field has been performed in order to explore the coherent flow features in the ascending aorta in the presence of a dysfunctional bileaflet mechanical heart valve.

RESULTS

The ability of proper orthogonal decomposition derived metrics to differentiate between heathy and dysfunctional cases is reported. Moreover, reduced-order modeling using proper orthogonal decomposition is thoroughly investigated not only for the velocity field but also for higher order flow characteristics such as time average wall shear stress, oscillatory shear index and viscous energy dissipation.

CONCLUSION

Considering these results, proper orthogonal decomposition can provide a rapid binary classifier to evaluate if the bileaflet mechanical valve deviates from its normal operating conditions. Moreover, the study shows that the size of the reduced-order model depends on which flow parameter is required to be reconstructed.

Two Strategies for the Dosage of Acenocoumarol Co-Administered with Rifampicin in Staphylococcal Prosthetic Valve Endocarditis

According to current European Society of Cardiology guidelines, for staphylococcal prosthetic valve endocarditis, rifampicin should be one of the drugs used. However, there is a concomitant need for vitamin K antagonists in patients with mechanical prostheses. It is widely known that rifampicin interacts with vitamin K antagonists (VKA), and this interaction makes it difficult to maintain the INR (international normalized ratio) value in the therapeutic range. We present two clinical cases of staphylococcal prosthetic valve endocarditis patients. Two different strategies for dealing with adverse drug interactions have been applied. In the first case, the dose of warfarin was up-titrated until the optimal INR value was obtained. In the second case, due to the history of labile INR values, a decision was made to modify the dosage of warfarin, taking into account pharmacological aspects of drug interactions.

Normal reference values for mechanical mitral prosthetic valve inner diameters and areas assessed by two-dimensional and real-time three-dimensional transesophageal echocardiography

It was previously observed that two dimensional (2D) Doppler derived and real-time three-dimensional (RT-3D) directly measured valve areas were smaller than reported manufacturer sizes. It may be helpful to obtain the ranges of inner diameters (IDs) and the geometric orifice area (GOA) during evaluation of prosthetic mitral valves. In this study, we aimed to provide reference dimensional parameters of bileflet mitral mechanical prosthetic valves. Patients with recent mitral valve replacement were examined by 2D and RT-3D transesophageal echocardiography (TEE) in the early postoperative period when the presence of pannus overgrowth was unlikely. Measurements of 2D IDs, 3D hinge to hinge (HHD) and edge to edge diameters (EED) and 3D GOA were obtained and compared with reported manufacturer sizes and areas. This study enrolled 126 patients with mitral prosthetic valves (38 ATS, 42 Carbomedics, 46 St. Jude Medical, all bileaflet). The measured 2D and 3D IDs and GOA were significantly smaller than reported manufacturer sizes in the majority of the valve sizes. This RT-3D TEE-guided study provides ranges of reference values for directly measured IDs and GOA of the three most commonly used mechanical mitral prosthetic valve types for the first time in a relatively large series.

Clinical outcomes and hemodynamic performance of Dafodil™ aortic and mitral pericardial bioprosthesis: 1-year results from Dafodil-1 first-in-human trial

BACKGROUND

Bioprosthesis has been increasingly implanted for the treatment of transvalvular disease across the world. A new Dafodil™ pericardial bioprosthesis (Meril Life Sciences Pvt. Ltd., India) recently approved by Conformité Européenne (CE) is a tri-leaflet, stented, bovine valve. The purpose of Dafodil-1 first-in-human trial was to evaluate clinical safety and performance (including hemodynamic parameters) of the Dafodil pericardial bioprosthesis in patients who underwent aortic or mitral valve replacement.

METHODS

This prospective, multicenter clinical trial enrolled 60 patients (Aortic: 30 patients; Mitral: 30 patients) from seven sites across India. Safety endpoints were early (≤30 days) and late (> 30 days) mortality and valve-related morbidity. The performance endpoints were hemodynamic performance, improvement in NYHA functional class, and change in the quality of life using SF-12v1 health survey.

RESULTS

From July 2017 to July 2018, 60 patients underwent implantation of the Dafodil pericardial bioprosthesis. Post-operatively, NYHA functional class significantly improved in all the patients (Aortic: 90% NYHA class-I and 10% NYHA class-II; Mitral: 96.55% NYHA class-I and 3.45% NYHA class-II; P < 0.001). There was no death in aortic valve replacement patients till 12-month. In mitral valve replacement patients, early mortalities occurred in three patients, and late mortality occurred in one patient; none of these were valve-related. Freedom from all-cause mortality reported was 93.33% at 12-month. Mean aortic pressure gradient decreased from 52.71 ± 24.47 mmHg [with 0.89 ± 0.70 cm² effective orifice area (EOA)] pre-operatively to 14.49 ± 6.58 mmHg (EOA: 1.85 ± 0.27 cm²) at 12-month. Overall, the mitral mean pressure gradient and EOA were 4.41 ± 1.69 mmHg and 2.67 ± 0.48 cm², respectively, at 12-month. Significant improvement (P < 0.05) in the patients' quality of life was reported at all follow-ups.

CONCLUSIONS

The clinical safety and performance of the Dafodil pericardial bioprosthesis were favourable at 12-month. Moreover, a study with a larger patient population and longer follow-up is warranted to further assess the device.

TRIAL REGISTRATION

Dafodil-1 trial has been prospectively registered on 10/07/2017 under Clinical Trial Registry-India (http://www.ctri.nic.in). (Registration number: CTRI/2017/07/009008).

Relationship between silent cerebral infarcts and quality of anticoagulation in patients with prosthetic mitral valves

OBJECTIVE

Although patients with prosthetic heart valves have an increased risk of clinically overt cerebrovascular events, evidence for the risk of silent cerebral infarction (SCI) is scarce. Serum neuron-specific enolase (NSE) is suggested to be a valid biomarker that allows for the quantification of the degree of neuronal injury. We aimed to assess whether NSE is elevated as a marker of recent SCI in patients with a prosthetic mitral valve.

METHODS

We measured the NSE levels in 103 patients with a prosthetic mitral valve (PMV), admitted to our outpatient clinics for routine evaluation. International normalized ratio (INR) and time in target therapeutic range (TTR) were noted as anticoagulation quality measures.

RESULTS

Most of the patients were females (58%), and a mean age was 65 years. NSE values of >12 ng/mL, suggesting a recent SCI, was detected in 25 patients (24%). NSE was negatively correlated with admission INR (r=-0.307, p=0.002). Multivariate analyses demonstrated subtherapeutic INR (INR <2.5) and suboptimal TTR as independent predictors of SCI [odds ratio (OR) 5.420; 95% confidence interval (CI) 1.589 to 18.483; p=0.007, and OR 4.149; 95% CI 1.019 to 16.949; p=0.047, respectively]. Being a current smoker (OR 10.798; 95% CI 2.520 to 46.272; p=0.001), large left atrium (OR 6.763; 95% CI 2.253 to 20.302; p=0.001), and not using aspirin (OR 10.526; 95% CI 1.298 to 83.333; p=0.027) were other independent predictors.

CONCLUSION

Our data suggest that silent brain infarcts are very prevalent among patients with a PMV, as one fourth of them had the event during their routine outpatient visit. Poor quality of anticoagulation partly explains the increased prevalence.