Natural history of venous thromboembolism

Associations of blood pressure in the third trimester and risk of venous thromboembolism postpartum

Studies on the associations of blood pressure (BP) and the risk of venous thromboembolism (VTE) had been performed neither among pregnant women nor in Chinese population. This study included participants of pregnant women from a retrospective multicenter cohort, between May 2020 and April 2023. Systolic BP (SBP) and diastolic BP (DBP) of the participants were measured in the third trimester. The incidences of VTE (including deep venous thrombosis and/or pulmonary embolism) at 42 days postpartum were followed. With regards to SBP, pregnant women in the Q1 (≤114 mmHg), Q2 (115-122 mmHg), and Q4 group (≥131 mmHg) had increased risk of VTE than those in Q3 group (123-130 mmHg), with ORs 4.48 [1.69, 11.85], 3.52 [1.30, 9.59], and 3.17 [1.12, 8.99], respectively. Compared with pregnant women with the Q4 of DBP (≥85 mmHg), women of Q1 (≤71 mmHg) were found to have elevated risk of VTE (OR 2.73 [1.25, 5.96]). A one standard deviation decrease of DBP (9 mmHg) was related with 37% elevated risk of VTE (OR 1.37 [1.05, 1.79]). This study demonstrated a U-shaped association of SBP in the third trimester and VTE postpartum and inverse association of DBP in the third trimester and VTE postpartum.

The Below-the-Knee Approach to Percutaneous Mechanical Thrombectomy for Lower Extremity Deep Venous Thrombosis: A Retrospective Single-Centre, Single-Arm Study

PURPOSE

The objective of this study was to evaluate the safety, efficacy, and feasibility of percutaneous mechanical thrombectomy (PMT) through a below-the-knee (BTK) approach for acute lower extremity deep venous thrombosis (DVT).

METHODS

A retrospective review of DVT patients treated with PMT by the BTK approach at our center from April 2022 to August 2023 was performed. Their preoperative demographics, intraoperative data, and postoperative outpatient outcomes were analyzed.

RESULTS

A total of 12 patients (67% men; mean age, 63 years) met the inclusion criteria. The BTK approach was successfully achieved in all patients through the posterior tibial vein (n = 1), anterior tibial vein (n = 2), and peroneal vein (n = 9). PMTs were achieved in 11 (92%) patients. Successful lysis (grade II and grade III lysis) was achieved in all patients with PMT. Four (33%) patients had residual venous occlusion over the popliteal vein. No intraoperative complications or bleeding events occurred in any of the patients.

CONCLUSION

PMT via BTK puncture seems to be a safe and effective approach for treating lower extremity DVT. It is reserved for highly select patients with a low risk of bleeding and is performed at centers that have experience with this procedure.

Blood pressure and risk of venous thromboembolism: a cohort analysis of 5.5 million UK adults and Mendelian randomization studies

AIMS

Evidence for the effect of elevated blood pressure (BP) on the risk of venous thromboembolism (VTE) has been conflicting. We sought to assess the association between systolic BP and the risk of VTE.

METHODS AND RESULTS

Three complementary studies comprising an observational cohort analysis, a one-sample and two-sample Mendelian randomization were conducted using data from 5 588 280 patients registered in the Clinical Practice Research Datalink (CPRD) dataset and 432 173 UK Biobank participants with valid genetic data. Summary statistics of International Network on Venous Thrombosis genome-wide association meta-analysis was used for two-sample Mendelian randomization. The primary outcome was the first occurrence of VTE event, identified from hospital discharge reports, death registers, and/or primary care records. In the CPRD cohort, 104 017(1.9%) patients had a first diagnosis of VTE during the 9.6-year follow-up. Each 20 mmHg increase in systolic BP was associated with a 7% lower risk of VTE [hazard ratio: 0.93, 95% confidence interval (CI): (0.92-0.94)]. Statistically significant interactions were found for sex and body mass index, but not for age and subtype of VTE (pulmonary embolism and deep venous thrombosis). Mendelian randomization studies provided strong evidence for the association between systolic BP and VTE, both in the one-sample [odds ratio (OR): 0.69, (95% CI: 0.57-0.83)] and two-sample analyses [OR: 0.80, 95% CI: (0.70-0.92)].

CONCLUSION

We found an increased risk of VTE with lower BP, and this association was independently confirmed in two Mendelian randomization analyses. The benefits of BP reduction are likely to outweigh the harms in most patient groups, but in people with predisposing factors for VTE, further BP reduction should be made cautiously.

Anatomical consideration of deep calf veins: application to catheter-directed thrombolysis

Purpose

An antegrade approach is frequently used in catheter-directed thrombolysis to remove deep-vein thrombosis. However, the antegrade approach is difficult when accessing veins with small diameters; therefore, understanding the variation of deep calf vein is important.

Methods

This study measured the diameters and surface areas of the proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein to determine which are preferable for venous access. This study dissected 132 legs from Korean and Thai cadavers. The proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein were scanned and measured.

Results

The mean diameter and surface area were largest for the proximal tibial vein, at 6.34 mm and 0.312 cm², respectively, followed by the anterior tibial vein (5.22 mm and 0.213 cm²), distal posterior tibial vein (3.29 mm and 0.091 cm²), and peroneal vein (3.43 mm and 0.081 cm²). The proximal posterior tibial vein and anterior tibial vein have large diameters and surface areas, which make them ideal for applying an antegrade approach in catheter-directed thrombolysis.

Conclusions

The distal posterior tibial vein and peroneal vein are not recommended due to their smaller surface areas and also the anatomical variations therein.

Concordance between clinical diagnosis of pulmonary thromboembolism at hospital discharge and anatomopathological diagnosis

Half of the cases of pulmonary thromboembolism (PTE) are not diagnosed because of its unspecific clinical presentation; in Mexico, autopsy data reveal a similar incidence to that of developed countries. The objective of this work was to know the concordance between the clinical diagnosis of PTE at hospital discharge and its autopsy diagnosis. The method used was a retrospective cohort study of cases with PTE diagnosis who attended from January 2005 to December 2013. Information was obtained from the autopsies registry and clinical charts. From 177,368 hospital discharges, there were 412 (6.74%) with PTE diagnosis. There were 13,559 deaths, with PTE diagnosis in 139 (1%) patients. There were 479 autopsies, and in 66 (14%) of whom PTE diagnosis was documented, the mean age was 55 years (range, 18–89 years). The premortem diagnosis of PTE at discharge was confirmed in 412 cases. Postmortem diagnosis of principal disease was medical in 49 (74%) and medical-surgical in 17 (26%) patients. We found that nine patients had the clinical diagnosis of PTE, unlike the postmortem diagnosis, which was reported in 66 autopsies. The above allows establishing a 1:7 ratio that represents 14%. D-dimer was determined in 11 cases (16%) and was positive in 8 (73%). Thromboprophylaxis was applied in 15 cases (23%). The study of necropsies and identification of discrepancies is needed to improve the diagnostic accuracy and healthcare quality. The evaluation of hemostasis biomarkers besides D-dimer can better describe the pro-thrombotic state, the risk of thrombosis, and its association with morbidity and mortality.

Restart TICrH: An Adaptive Randomized Trial of Time Intervals to Restart Direct Oral Anticoagulants after Traumatic Intracranial Hemorrhage

Anticoagulants prevent thrombosis and death in patients with atrial fibrillation and venous thromboembolism (VTE) but also increase bleeding risk. The benefit/risk ratio favors anticoagulation in most of these patients. However, some will have a bleeding complication, such as the common trip-and-fall brain injury in elderly patients that results in traumatic intracranial hemorrhage. Clinicians must then make the difficult decision about when to restart the anticoagulant. Restarting too early risks making the bleeding worse. Restarting too late risks thrombotic events such as ischemic stroke and VTE, the indications for anticoagulation in the first place. There are more data on restarting patients with spontaneous intracranial hemorrhage, which is very different than traumatic intracranial hemorrhage. Spontaneous intracranial hemorrhage increases the risk of rebleeding because intrinsic vascular changes are widespread and irreversible. In contrast, traumatic cases are caused by a blow to the head, usually an isolated event portending less future risk. Clinicians generally agree that anticoagulation should be restarted but disagree about when. This uncertainty leads to long restart delays causing a large, potentially preventable burden of strokes and VTE, which has been unaddressed because of the absence of high quality evidence. Restart Traumatic Intracranial Hemorrhage (the "r" distinguished intracranial from intracerebral) (TICrH) is a prospective randomized open label blinded end-point response-adaptive clinical trial that will evaluate the impact of delays to restarting direct oral anticoagulation (1, 2, or 4 weeks) on the composite of thrombotic events and bleeding in patients presenting after traumatic intracranial hemorrhage.

Cardiac thrombotic stability determined by contrast-enhanced echocardiography: investigative protocol and preliminary results

Objective

This study’s intent was to test a new system for scoring cardiac thrombotic stability, based on contrast-enhanced ultrasound (CEUS).

Methods

We used human whole blood for an in vitro thrombotic model involving 1-h (T_1h) and 7-day (T_7d) subsets. The T_1h group was monitored for 1 h continuously to observe for the formation of a new thrombus on the original thrombus base. Changes in thrombotic CEUS images, histologic features, and shear wave elastography were recorded over time. We also studied 28 patients diagnosed with cardiac thrombi, each examined by transthoracic echocardiography and CEUS.Thrombi were scored for substrate (T_s) and hardness (T_h) based on the visualized degree of contrast penetration into the thrombi. Statistical analyses of T_s and T_h reflected thrombolytic time and risk of embolism to other organs.

Results

Histologically, the loosely constructed ends of in vitro thrombi solidified over time. In addition, the average Young’s modulus of thrombi over time indicated a progressive increase in hardness. Contrast-enhancing agents were able to penetrate fresh, loose thrombi only, not chronic, stable thrombi. As T_s and T_h increased, prolonged thrombolytic time and greater risk of embolism to other organs were apparent.

Conclusions

Our data suggest that this new CEUS scoring system correlates well with cardiac thrombotic hardness and the quality of its underlying substrate, serving to quantify thrombotic stability.

Histologic assessment of lower extremity deep vein thrombus from patients undergoing percutaneous mechanical thrombectomy

BACKGROUND

Histologic analyses of deep vein thrombi (DVTs) have used autopsy samples and animal models. To the best of our knowledge, no previous study has reported on thrombus composition after percutaneous mechanical extraction. Because elements of chronicity and organization render thrombus resistant to anticoagulation and thrombolysis, a better understanding of clot evolution could inform therapy.

METHODS

We performed a histologic evaluation of DVTs from consecutive patients who had undergone mechanical thrombectomy for extensive iliofemoral DVTs using the Clottriever/Flowtriever device (Inari Medical, Irvine, Calif). The DVTs were scored using a semiquantitative method according to the degree of fibrosis (collagen deposition on trichrome staining) and organization (endothelial growth with capillaries and fibroblastic penetration).

RESULTS

Twenty-three specimens were available for analysis, with 20 presenting as acute DVT (≤14 days from symptom onset). Of the 23 patients, 11 (48%) had had >5% fibrosis (ie, collagen deposition) and 14 (61%) had had >5% organization (ie, endothelial growth, capillaries, fibroblasts). Four patients with acute DVT had had ≥25% organized thrombus and two had had ≥25% collagen deposition. Of the 20 patients with acute DVT, 40% had had >5% fibrosis and 55% had had >5% organization. The acuity of DVT did not correlate with the amount of fibrosis or organizing scores.

CONCLUSIONS

A large proportion of patients with acute DVT will have histologic elements of chronicity and fibrosis. A better understanding of the relationship between such elements and the response to anticoagulant agents and fibrinolytic drugs could inform our approach to therapy.

Thrombus Composition and Efficacy of Thrombolysis and Thrombectomy in Acute Ischemic Stroke

Thrombi retrieved from patients with acute ischemic stroke are highly heterogeneous. Recent data suggest that thrombus composition may impact on mechanical thrombectomy, the number of recanalization manoeuvres, resistance to retrieval, and on thrombolytic potential. Our aim was to summarize evidence describing the impact of thrombus composition on efficacy of mechanical thrombectomy and thrombolysis in patients with acute ischemic stroke. The scoping review methodology guided by the Joanna Briggs Institute, an adaption of the Arksey and O'Malley, was followed. Comprehensive searches were conducted in MEDLINE, EMBASE, SCOPUS, and Web of Science. Articles were classified into 4 key themes: (1) composition of stroke thrombi, (2) thrombus composition and mechanical thrombectomy, (3) thrombus composition and thrombolytic therapy, and (4) novel imaging and endovascular approaches. Our search identified 698 articles published from 1987 to June 2020. Additional articles were extracted from reference lists of the selected articles. Overall, 95 topic-specific articles identified for inclusion published in 40 different journals were included. Reports showed that thrombus composition in stroke was highly heterogeneous, containing fibrin, platelets, red blood cells, VWF (von Willebrand Factor), and neutrophil extracellular traps. Thrombi could roughly be divided into fibrin- and red blood cell-rich clots. Fibrin-rich clots were associated with increased recanalization manoeuvres, longer procedure time, and less favorable clinical outcomes compared with red blood cell-rich clots. Advances in detection or treatment of thrombi that take into account clot heterogeneity may be able to improve future endovascular and thrombolytic treatment of stroke.

The role of platelets in thrombus fibrosis and vessel wall remodeling after venous thrombosis

PURPOSE

Platelets are known to play an important role in venous thrombogenesis, but their role in thrombus maturation, resolution, and postthrombotic vein wall remodeling is unclear. The purpose of this study was to determine the role that circulating platelets play in the later phases of venous thrombosis.

METHODS

We used a murine inferior vena cava (IVC) stenosis model. Baseline studies in untreated mice were performed to determine an optimal postthrombotic time point for tissue harvest that would capture both thrombus maturation/resolution and postthrombotic vein wall remodeling. This time point was found to be postoperative day 10. After undergoing IVC ultrasound on day 2 to confirm venous thrombus formation, mice were treated with a daily injection of platelet-depleting antibody (anti-GP1bα) to maintain thrombocytopenia or with control IgG until postoperative day 10, at which time IVC and thrombi were harvested and thrombus length, volume, fibrosis, neovascularization, and smooth muscle cell invasion analyzed. Vein wall fibrosis and intimal thickening were also determined.

RESULTS

Mice that were made thrombocytopenic after venous thrombogenesis had thrombi that were less fibrotic, with fewer invading smooth muscle cells. Furthermore, thrombocytopenia in the setting of venous thrombosis resulted in less postthrombotic vein wall intimal thickening. Thrombus volume did not differ between thrombocytopenic mice and their control peers.

CONCLUSIONS

This work suggests that circulating platelets contribute to venous thrombus maturation, fibrosis, and adverse vein wall remodeling, and that that inhibition of platelet recruitment may decrease thrombus and vein wall fibrosis, thus helping thrombolysis and preventing postthrombotic syndrome.

Modified one-session endovascular treatment for deep venous thrombosis with high risk of pulmonary embolism: Short-term outcomes

OBJECTIVES

To evaluate the safety and short-term outcomes of the modified one-session endovascular treatment with inferior vena cava filter placement and retrieval in one stage for the treatment of acute lower extremity deep vein thrombosis.

METHOD

Twenty-three patients with unilateral acute lower extremity deep vein thrombosis underwent modified one-session endovascular treatments, which were performed in one stage. Inferior vena cava filter placement without detachment, thrombectomy, and inferior vena cava filter retrieval were performed in one stage. Angioplasty and stent implantation were performed for patients with iliac vein stenosis. Venography was performed to identify the clearance of the thrombus. Color Doppler ultrasound and/or venography were conducted during the follow-up.

RESULTS

A total of 20/23 (87%) patients with thrombus removal rate >90% successfully underwent modified one-session endovascular treatment. inferior vena cava filters were detached in 3/23 (13%) patients achieving 50%-90% thrombus removal rate. Twenty-one iliac vein stents were implanted in 21/23 (91%) patients with iliac vein stenosis. After treatment, the differences in the circumferences of the affected limb and the healthy limb both significantly decreased. No procedure-related death, symptomatic pulmonary embolism, or major bleeding occurred. During the 12-25 months of follow-up, iliac vein stents and lower extremity veins maintained patent.

CONCLUSIONS

The modified one-session endovascular treatment with one-stage inferior vena cava filter placement and retrieval might be safe for the treatment of acute lower extremity deep vein thrombosis, and the early clinical outcomes are satisfactory. Placing and retrieving an inferior vena cava filter in one session could safeguard the endovascular interventions as well as reduce the filter-related complications associated with long dwelling times.

Catheter-directed thrombolysis through anterior tibial vein for treating acute extensive deep venous thrombosis

OBJECTIVE

The objective of this study was to evaluate the feasibility, efficacy, and safety of catheter-directed thrombolysis (CDT) through an anterior tibial vein approach for acute extensive lower extremity deep venous thrombosis (DVT).

METHODS

There were 125 consecutive patients with acute extensive lower extremity DVT who received CDT through an anterior tibial vein approach between October 2014 and June 2017. The patients with iliac vein compression syndrome were treated with balloon dilation and stent implantation after CDT. The thrombus score differences, limb circumference differences, venous patency, and complications were retrospectively analyzed.

RESULTS

The anterior tibial vein approach was successfully achieved in 118 patients (94.40% [118/125]). The mean thrombolysis time was 5.28 ± 1.10 days, and the average dose of urokinase was 3,903,400 ± 766,900 IU. Metal stents were placed in 50 patients (42.37% [50/118]). There were 109 patients (92.37% [109/118]) who had successful lysis (grade II and grade III lysis); 31 patients (91.18% [31/34]) achieved grade III lysis (no residual thrombus) within 3 days of symptom onset. In contrast, only 33.96% (18/53) of those treated within 4 to 7 days and 9.68% (3/31) of those treated after 7 days achieved grade III lysis. Compared with findings before CDT, the limb circumference above and below the knee was significantly reduced (7.22 ± 2.54 cm vs 1.58 ± 0.75 cm and 5.14 ± 1.41 cm vs 1.19 ± 0.49 cm, respectively). The incidence of bleeding was 10.17% (12/118). Six patients had puncture site bleeding, and three patients suffered major bleeding. One puncture site infection and two catheter-directed infections were observed during treatment. Two patients had accidental anterior tibial artery injury and recovered without complications, and no nerve injury occurred. During a follow-up of 19.39 ± 7.47 months (6-32 months), femoral venous insufficiency and popliteal venous insufficiency were present in 21.65% (21/97) and 30.93% (30/97) of the patients. The overall patency and post-thrombotic syndrome rates were 83.51% (81/97) and 21.65% (21/97).

CONCLUSIONS

CDT through an anterior tibial vein approach is a feasible, effective, and safe method for acute extensive lower extremity DVT patients. In addition, the anterior tibial vein approach can be an alternative to the traditional CDT approach.

Can thrombus age guide thrombolytic therapy?

Venous thrombosis (VT) is a common yet complex clinical condition that has shown minimal alteration in clinical management for decades. It is well known that thrombus evolves structurally over time, with complex changes resulting from the interplay between coagulation factors, cytokines, leukocytes and a myriad of other factors. Our current treatment options are most effective in the acute thrombus, which is composed predominantly of a loose mesh of fibrin and red blood cells (RBCs), making current anticoagulation therapies and thrombolytics quite effective in treatment. Later stages of thrombus are more cellular containing leukocytes, and develop a fibrotic collagenous framework that is more resistant to our current treatments. Understanding the biology of an evolving thrombus will allow us to tailor our treatment and optimize outcomes, as well as focus on novel therapies for the treatment of chronic thrombus. Given the morbidity and mortality of both post thrombotic syndrome (PTS) in patients with deep VT, as well as chronic thromboembolic pulmonary hypertension (CTEPH) in patients with pulmonary embolism (PE), new and innovative therapies must continue to be explored to help prevent these potentially devastating conditions.

Animal models of venous thrombosis

Venous thrombosis (VT) is a prevalent clinical condition with significant adverse sequela or mortality. Anticoagulation and pharmacologic or pharmacomechanical thrombolytic therapies are the mainstays of VT treatment. An understanding of thrombosis biology will allow for more effective VT-tailored diagnosis and therapy. In vivo models of thrombosis provide indispensable tools to study the pathogenesis of thrombus formation and to evaluate novel therapeutic or preventive adjuncts for VT management or prevention. In this article, we review the most prominent in vivo models of VT created in rodents and swine species and outline how each model can serve as a useful tool to promote our understanding of VT pathogenesis and to examine novel therapies.

Surgical operative time increases the risk of deep venous thrombosis and pulmonary embolism in robotic prostatectomy

Background and Objectives:

To evaluate the effect of operative time on the risk of symptomatic venous thromboembolic events (VTEs) in patients undergoing robot-assisted radical prostatectomy (RARP).

Methods:

We reviewed the records of all patients at our institution who underwent RARP by a single surgeon from January 2007 until April 2011. Clinical and pathologic information and VTE incidence were recorded for each patient and analyzed by use of logistic regression to evaluate for association with VTE risk. All patients had mechanical prophylaxis, and beginning in February 2008, a single dose of unfractionated heparin, 5000 U, was administered before surgery.

Results:

A total of 549 consecutive patients were identified, with a median follow-up period of 8 months. During the initial 30 days postoperatively, 10 patients (1.8%) had a VTE (deep venous thrombosis in 7 and pulmonary embolism in 3). The median operative time was 177 minutes (range, 121–360 minutes). An increase in operative time of 30 or 60 minutes was associated with 1.6 and 2.8 times increased VTE risks. A 5-point increase in body mass index and need for blood transfusion were also associated with increased risk of VTEs (odds ratios of 2.0 and 11.8, respectively). Heparin prophylaxis was not associated with a significant VTE risk reduction but also was not associated with a significant increase in estimated blood loss (P = .23) or transfusion rate (P = .37).

Conclusion:

A prolonged operative time increases the risk of symptomatic VTEs after RARP. Future studies are needed to evaluate the best VTE prophylactic approach in patients at risk.

Prognostic significance of arterial and venous thrombosis in resected specimens for non-small cell lung cancer

BACKGROUND

Venous thromboembolism(VTE) is common after pneumonectomy for malignancy and predicts poor survival. Routine screening for VTE with noninvasive tests has low sensitivity and specificity. Biopsy of lung has a place in establishing the nature and severity of the vascular alterations. In this study, we investigated the incidence, clinical and pathological characteristics of thrombosis in excised specimens after pneumonectomy, and its association with survival rate in patients with non-small cell lung cancer (NSCLC).

METHODS

The studied population consisted 94 consecutive patients after pneumonectomy for NSCLC in Beijing Chao-Yang Hospital, The excised tissue specimens were stained by haematoxylin & eosin staining (HE) to observe thrombosis events. All the patients were followed up for 2years. The survival data was analyzed by Kaplan-Meier analysis.

RESULTS

Overall thrombosis events occurred in 56 (59.6%) of 94 NSCLC cases, pulmonary arterial thrombosis was found in 24 cases, and pulmonary venous thrombosis was found in 32 cases. Furthermore, 30 of 56 cases with thrombosis were accompanied by tumor emboli or tumor vascular infiltrating. Thrombosis risk was associated with cancer grade (P=0.005). Kaplan-Meier analysis showed that patients with thrombosis had lower survival rate than those without thrombosis (P=0.025).

CONCLUSIONS

The incidence of thrombosis in excised tissue after pneumonectomy was high in patients with NSCLC, and it may be a marker of poor outcome.

Should we look for silent pulmonary embolism in patients with deep venous thrombosis?

Background

Asymptomatic or silent pulmonary embolism (S-PE) in patients with deep vein thrombosis has been the focus of numerous publications with the objective of determining the incidence of S-PE and assessing whether its existence has any clinical or therapeutic consequences that outweigh the risks associated with the diagnostic tests performed and the increased healthcare costs. The objectives were to assess the incidence of S-PE using computed tomography angiogram (CTA), to understand the epidemiological factors that might trigger embolism, and to assess whether D-dimer (DD) predicts the existence of S-PE’s.

Methods

A prospective and consecutive assessment of 103 hospitalized patients with lower limb DVT in the absence of PE symptoms, using CT scan. DD was quantified before anticoagulation. The risk factors and characteristics of the DVT were studied. A three-year follow-up assessing risk recurrence and clinical outcome was performed.

Results

The incidence of S-PE was 66%. In 77% of these cases, the main and lobar pulmonary arteries were affected. Iliac and femoral DVTs most often produced S-PE. ROC curve with a DD value higher than 578 ng/ml provided good sensitivity but low specificity to identify patients with S-PE. Diagnosis entailed higher hospitalization expenses. No significant recurrence rate of thrombotic events was observed in the S-PE group during the follow-up.

Conclusions

The incidence of S-PE in lower-limb DVT is high, but in the absence of symptoms, diagnosis does not appear to be necessary, as there are no short- or long-term clinical or therapeutic consequences.

Elevated hyaluronan levels in patients with rheumatic mitral stenosis and pulmonary arterial thromboembolism

INTRODUCTION

The role of hyaluronan (HA) was previously demonstrated in patients with idiopathic pulmonary arterial hypertension (PAH). Mitral stenosis (MS) and pulmonary arterial thromboembolism (PTE) are important health problems that can cause pulmonovascular pathology. Pulmonary arterial hypertension develops especially in untreated patients with severe MS and most of patients with PTE. However, there is no data about HA levels in patients with MS and PTE. In this study, we investigated HA levels in patients with rheumatic MS and PTE.

METHOD

Study population was divided into three groups. MS group consisted of 18 patients with moderate or severe MS. PTE group consisted of 16 patients with PTE. Control group consisted of 15 subjects without cardiac and pulmonary disease. Percutaneous mitral balloon valvuloplasty (PMV) was performed on all patients in MS group. Mitral gradients and systolic pulmonary arterial pressure (sPAP) were measured in all patients. HA levels were measured at baseline and first month after PMV.

RESULTS

Mean sPAP±SD (mmHg) was 23±3 in the control group, 44±9 in the MS group and 66±11 in the PTE group (p<0.001). Baseline serum HA levels were significantly correlated with sPAP(echo) (r=0.332 p=0.03) and sPAP(cath) (r=0.559, p=0.007). Serum HA levels (ng/ml) in MS were significantly higher compared to controls [39±14 vs 24±11; p=0.01]. Patients in PTE group had the highest HA levels (61±21; p<0.001). Serum HA levels were significantly decreased at the first month after PMV in patients with MS [MS group: 39±14 (ng/ml), after PMV: 31±8; p=0.03].

CONCLUSION

This is the first article showing that both MS and PTE can cause increased serum HA levels. HA levels were decreased with PMV procedure in patients with MS.

Pulmonary Embolic Disorders

Deaths due to pulmonary thromboemboli are frequently encountered by the forensic pathologist and account for a significant percentage of sudden, unexpected deaths. Diagnosing these straightforward cases is often not a challenge, but unfortunately some cases in which a thromboembolism is expected can become complicated. Occasionally, a postmortem clot may mimic a thromboembolism and lead to a mistaken diagnosis, and in other situations it may become paramount to attempt to age a thrombus as part of a medicolegal lawsuit. Additionally, many individuals use the less specific term, “pulmonary emboli”, when referring to these cases in which a portion of a thrombus, usually originating in the deep veins of the lower extremities, breaks off and travels to the pulmonary vasculature bed where it occludes vessels and leads to a rapid demise. One must remember, though, that several other materials and tissues including fat, amniotic fluid, air, tumors, solid organs, synthetic materials, and parasites may be displaced and embolize to the lungs and cause significant disease. In the following pages we will provide a thorough review of pulmonary embolic disorders, focusing on those diseases most likely to be encountered by the forensic pathologist. The aim of this review is to aid the pathologist in using proper terminology, diagnosing various types of embolic disorders, and recognizing potential mimics.