Diagnosis, treatment & management of prosthetic valve thrombosis: the key considerations

Monocyte to HDL ratio may predict thrombosis in patients with mechanical mitral and aortic valve prosthesis

Increased inflammatory biomarkers have been reported in prosthetic heart valve thrombosis (PHVT). Monocyte to HDL ratio (MHR) and albumin to CRP levels (CAR) are two biomarkers used widely for systemic inflammation but there is a lack of data on prosthetic heart valves. This study aimed to find out the potential predictive value of MHR and CAR for PHVT. Patients who had the diagnosis of mechanical mitral/aortic PHVT and normally functioning prosthesis were retrospectively analyzed. Laboratory data including complete blood count and biochemistry were recorded. Transesophageal echocardiography was performed to diagnose PHVT. The study included 118 patients with mechanical PHVT and 120 patients with normally functioning prosthesis. White blood count, monocyte levels, C-reactive protein, MHR and CAR were significantly higher whereas the lymphocyte, HDL and INR levels on admission were lower in patients with PHVT. Multivariate analysis showed that as well as inadequate anticoagulation, MHR, but not CAR, was found to be an independent predictor of thrombosis in patients with PHVT. Receiver operating characteristic curve analysis was performed to detect the best cut-off value of MHR in the prediction of thrombosis in patients with prosthetic valves. MHR level of > 12.8 measured on admission, yielded an AUC value of 0.791 [(CI 95% 0.733-0.848 p < 0.001) sensitivity 71%, specificity 70%]. Inadequate anticoagulation is the primary cause that leads to thrombosis in mechanical prosthetic valves. Increased MHR, but not CAR, was also shown to be an independent predictor of thrombosis in patients with mechanical mitral and aortic prosthetic valves.

Mechanical prosthetic mitral valve obstruction: Pannus or thrombus? A case report

Substitution of a defective heart valve with a prosthetic heart valve turns the native disease for prosthesis-related complications. One of the most serious and dreaded complications is prosthetic valve obstruction. It is either the result of a thrombus or pannus formation. For the evaluation of prosthetic valve obstruction, transthoracic echography and fluoroscopy provide functional information but may not provide information about the etiology of the obstruction, unlike multidetector computed tomography (MDCT) which allows a more precise etiological diagnosis to guide the therapeutic attitude. Here, we report a case of a mechanical prosthetic mitral valve obstruction in a 45-year-old patient in whom the diagnosis of pannus was retained on the basis of clinical, biological, and imaging data. The differentiation between thrombus and pannus is crucial because it conditions the therapeutic attitude. Advanced imaging specially MDCT options should be considered whenever mechanical prosthesis valve obstruction is suspected.

Diagnosis of Left-Sided Mechanical Prosthetic Valve Thrombosis: A Pictorial Review

Although transcatheter valve therapy is rapidly evolving, surgical valve replacement is still required in many patients with severe left-side valve stenosis or regurgitation, the mechanical bi-leaflet heart valve being the standard prosthesis type in younger patients. Moreover, the prevalence of valvular heart disease is steadily increasing, especially in industrialized countries, and the problem of lifelong efficient anticoagulation of these patients remains fundamental, especially in the context where vitamin K antagonists continue to be the current standard of anticoagulation despite a level of oscillating anticoagulation. In this setting, avoiding prosthetic valve thrombosis after surgery is the number one objective for both the patient and the responsible physicians. Although rare, this complication is life threatening, with the sudden onset of acute cardiac failure such as acute pulmonary edema, cardiogenic shock, or sudden cardiac death and inadequate anticoagulation remaining the leading cause of prosthesis thrombosis, along with other risk factors. The availability of multimodal imaging techniques enables and encompasses to a full extent the diagnosis of mechanical valve thrombosis. The gold-standard diagnostic methods are transthoracic and transesophageal echocardiography. Moreover, 3D ultrasound has undoubted value in giving a more accurate description of the thrombus's extension. When transthoracic and transesophageal echocardiography are uncertain, the multidetector computer tomography examination is an important complementary imaging method. Fluoroscopy is also an excellent tool for evaluating the mobility of prosthetic discs. Each method complements the other to differentiate an acute mechanical valve thrombosis from other prosthetic valve pathologies such as pannus formation or infective endocarditis and aids the physician in accurately establishing the treatment method (surgical or pharmaceutical) and its optimal timing. The aim of this pictorial review was to discuss from an imagistic perspective the mechanical prosthetic aortic and mitral valve thrombosis and to provide an overview of the essential role of non-invasive exploration in the treatment of this severe complication.

Thrombolysis or Surgery in Patients With Obstructive Mechanical Valve Thrombosis: The Multicenter HATTUSHA Study

BACKGROUND

Prosthetic valve thrombosis (PVT) is one of the life-threatening complications of prosthetic heart valve replacement. Due to the lack of randomized controlled trials, the optimal treatment of PVT remains controversial between thrombolytic therapy (TT) and surgery.

OBJECTIVES

This study aimed to prospectively evaluate the outcomes of TT and surgery as the first-line treatment strategy in patients with obstructive PVT.

METHODS

A total of 158 obstructive PVT patients (women: 103 [65.2%]; median age 49 years [IQR: 39-60 years]) were enrolled in this multicenter observational prospective study. TT was performed using slow (6 hours) and/or ultraslow (25 hours) infusion of low-dose tissue plasminogen activator (t-PA) (25 mg) mostly in repeated sessions. The primary endpoint of the study was 3-month mortality following TT or surgery.

RESULTS

The initial management strategy was TT in 83 (52.5%) patients and surgery in 75 (47.5%) cases. The success rate of TT was 90.4% with a median t-PA dose of 59 mg (IQR: 37.5-100 mg). The incidences of outcomes in surgery and TT groups were as follows: minor complications (29 [38.7%] and 7 [8.4%], respectively), major complications (31 [41.3%] and 5 [6%], respectively), and the 3-month mortality rate (14 [18.7%] and 2 [2.4%], respectively).

CONCLUSIONS

Low-dose and slow/ultraslow infusion of t-PA were associated with low complications and mortality and high success rates and should be considered as a viable treatment in patients with obstructive PVT.

Recent Advances in the Rheumatic Fever and Rheumatic Heart Disease Continuum

Nearly a century after rheumatic fever (RF) and rheumatic heart disease (RHD) was eradicated from the developed world, the disease remains endemic in many low- and middle-income countries (LMICs), with grim health and socioeconomic impacts. The neglect of RHD which persisted for a semi-centennial was further driven by competing infectious diseases, particularly the human immunodeficiency virus (HIV) pandemic. However, over the last two-decades, slowly at first but with building momentum, there has been a resurgence of interest in RF/RHD. In this narrative review, we present the advances that have been made in the RF/RHD continuum over the past two decades since the re-awakening of interest, with a more concise focus on the last decade’s achievements. Such primary advances include understanding the genetic predisposition to RHD, group A Streptococcus (GAS) vaccine development, and improved diagnostic strategies for GAS pharyngitis. Echocardiographic screening for RHD has been a major advance which has unearthed the prevailing high burden of RHD and the recent demonstration of benefit of secondary antibiotic prophylaxis on halting progression of latent RHD is a major step forward. Multiple befitting advances in tertiary management of RHD have also been realized. Finally, we summarize the research gaps and provide illumination on profitable future directions towards global eradication of RHD.

Thrombosis associated with ventriculoatrial shunts

Ventriculoatrial shunts are the most common second-line procedure for cases in which ventriculoperitoneal shunts are unsuitable. Shunting-associated thrombosis is a potentially life-threatening complication after ventriculoatrial shunt insertion. The overall prevalence of this complication is still controversial because of substantial differences in the numbers found in studies using clinical data and in those analyzing postmortem findings. The etiology of thrombosis may be multifactorial, including shunt catheter itself, contents of cerebrospinal fluid, shunt infection, and genetic disorder. The clinical presentation can vary widely, ranging from asymptomatic to a life-threatening condition. Timely recognition of thromboembolic lesions is critical for treatment. However, early diagnosis and management is still challenging because of a relatively long asymptomatic latency and lack of clear guideline recommendations. The purpose of this review is to provide an overview of ventriculoatrial shunt thrombosis, especially to focus on its etiopathogenesis, diagnosis, treatment, and prevention.

The Global Impact of Rheumatic Heart Disease

PURPOSE OF REVIEW

Rheumatic heart disease (RHD) is a neglected disease of poverty, which presents challenges for patients, communities, and health systems. These effects are magnified in low resource countries, which bear the highest disease burden. When considering the impact of RHD, it is imperative that we widen our lens in order to better understand how RHD impacts the over 40 million people currently living with this preventable condition and their communities. We aimed to perform an updated literature review on the global impact of RHD, examining a broad range of aspects from disease burden to impact on healthcare system to socioeconomic implications.

RECENT FINDINGS

RHD accounts for 1.6% of all cardiovascular deaths, resulting in 306,000 deaths yearly, with a much higher contribution in low- and middle-income countries, where 82% of the deaths occurred in 2015. RHD can result in severe health adverse outcomes, markedly heart failure, arrhythmias, stroke and embolisms, and ultimately premature death. Thus, preventive, diagnostic and therapeutic interventions are required, although insufficiently available in undersourced settings. As examples, anticoagulation management is poor in endemic regions - and novel oral anticoagulants cannot be recommended - and less than 15% of those in need have access to interventional procedures and valve replacement in Africa. RHD global impact remains high and unequally distributed, with a marked impact on lower resourced populations. This preventable disease negatively affects not only patients, but also the societies and health systems within which they live, presenting broad challenges and high costs along the pathway of prevention, diagnosis, and management.

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.

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.

Prosthetic Aortic Valve Thrombosis Complicated by Left Main Coronary Artery Bifurcation Embolism: Case Report and Review of Literature

Coronary embolism due to prosthetic valve thrombosis is a rare cause of acute coronary syndrome. We report the challenging case of a 66-year-old female patient with non-ST-elevation myocardial infarction caused by left main coronary artery bifurcation embolism in the setting of mechanical aortic valve thrombosis. The patient was treated with intravenous thrombolysis. Four hours later, she suffered an anterior ST-elevation myocardial infarction due to left anterior descending artery embolization. Repeat coronary angiogram showed complete disappearance of the LMCA embolus with only distal LAD occlusion. The patient was further treated medically with excellent outcome.

Thrombolytic treatment of prosthetic valve thrombosis: a study using Urokinase

OBJECTIVE

We analysed the efficacy and safety of thrombolytic therapy with urokinase in patients with prosthetic valve thrombosis.

METHODS

Twenty-three patients with valve thrombosis received thrombolytic treatment using urokinase. First, a 250,000 IU intravenous bolus injection was administered as a loading dose, followed by intravenous infusion of 100,000 IU/h for 10 h and anticoagulation with low molecular weight heparin every day. The maximum treatment time was 5 days, i.e., until the transvalvular pressure gradient was normal or close to normal. Transthoracic echocardiography (TTE) was used every 12 h to monitor whether the thrombus was reduced and whether there was haemodynamic improvement. Routine blood tests, the prothrombin time (PT), international normalized ratio (INR) and complications were observed every day.

RESULTS

Sixteen (69.6%) patients were successfully treated with thrombolytic therapy: 2/2 (100%) aortic valves and 14/21 (66.7%) mitral valves. The partial success rate of this study was 13.0% (3/23). Four patients did not show any improvement in haemodynamics. Two cases had slight urine haemorrhage. One patient died of severe cerebral haemorrhage and shock. The overall mortality was 13.0% (3/23), including two patients who died after subsequent surgery.

CONCLUSION

Urokinase is more convenient and successful in the treatment of PVT. More experience may make TT the optimal treatment for PVT, especially in high-risk surgical situations.

The relationship between incomplete surgical obliteration of the left atrial appendage and thromboembolic events after mitral valve surgery (from the ISOLATE Registry)

Left atrial appendage (LAA) is a common site of thrombus formation especially in patients with atrial fibrillation (AF). Complete surgical LAA closure (cSLC) is the surgical aim, however incomplete surgical LAA closure (iSLC) is not rare. In this study, we aimed to evaluate the risk of thromboembolic complications (TEC) in AF patients with iSLC after mitral valve surgery. A total of 101 AF patients (mean age: 61.8 ± 11.8 years; male:32), who underwent surgical suture ligation during mitral valve surgery were enrolled in this retrospective study. All patients underwent transthoracic and transesophageal echocardiography (TEE) at least 3 months after surgery. The primary outcome was the occurrence of TEC including any ischemic stroke, transient ischemic attack, coronary or peripheral embolism. TEE examination revealed cSLC in 66 (65.3%) and iSLC in 35 patients (34.6%). A total of 12 TECs (11.9%) occurred during a mean follow-up time of 41.1 ± 15.6 months. TECs were found to be significantly higher in the iSLC group (25.7% vs 4.5%, p = 0.002). The prevalence of iSLC was significantly higher in patients with TEC (75 vs. 29.2%, p = 0.002). High CHA₂DS₂-VASc Score and iSLC were found to be independent predictors of TEC. Long term TEC free survival was found to be significantly decreased in patients with iSLC. The presence of iSLC was associated with a significantly increased risk of TEC in AF patients after mitral valve surgery. Routine intraoperative and postoperative screening for iSLC by TEE and long-term strict anticoagulation therapy are recommended in these patients.