Annals Internal Medicine, Author Interviews, Blood Clots, Emergency Care, Kaiser Permanente, Pulmonary Disease, UC Davis / 13.11.2018

[caption id="attachment_45809" align="alignleft" width="160"]Dr-David R Vinson Dr. Vinson[/caption] MedicalResearch.com Interview with: David R. Vinson, MD Department of Emergency Medicine Kaiser Permanente Sacramento Medical Center Sacramento, CA MedicalResearch.com: What is the background for this study? What are the main findings? Response: At least one-third of emergency department (ED) patients with acute blood clots in the lung, or pulmonary embolism (PE), are eligible for expedited discharged to home, either directly from the ED or after a short (<24 hour) period of observation. Yet in in most hospitals in the U.S. and around the world nearly all ED patients with acute PE are hospitalized. These unnecessary hospitalizations are a poor use of health care resources, tie up inpatient beds, and expose patients to the cost, inconvenience, and risk of inpatient care. The better-performing medical centers have two characteristics in common: they help their physicians identify which PE patients are candidates for outpatient care and they facilitate timely post-discharge follow-up. At Kaiser Permanente Northern California (KPNC), we have had the follow-up system in place for some time, but didn’t have a way to help our physicians sort out which patients with acute PE would benefit from home management. To correct this, we designed a secure, web-based clinical decision support system that was integrated with the electronic health record. When activated, it presented to the emergency physician the validated PE Severity Index, which uses patient demographics, vital signs, examination findings, and past medical history to classify patients into different risk strata, correlated with eligibility for home care. To make use of the PE Severity Index easier and more streamlined for the physician, the tool drew in information from the patient’s comprehensive medical records to accurately auto-populate the PE Severity Index. The tool then calculated for the physician the patient’s risk score and estimated 30-day mortality, and also offered a site-of-care recommendation, for example, “outpatient management is often possible.” The tool also reminded the physician of relative contraindications to outpatient management. At the time, only 10 EDs in KPNC had an on-site physician researcher, who for this study served as physician educator, study promotor, and enrollment auditor to provide physician-specific feedback. These 10 EDs functioned as the intervention sites, while the other 11 EDs within KPNC served as concurrent controls. Our primary outcome was the percentage of eligible ED patients with acute PE who had an expedited discharge to home, as defined above. During the 16-month study period (8-month pre-intervention and 8-months post-intervention), we cared for 1,703 eligible ED patients with acute PE. Adjusted home discharge increased at intervention sites from 17% to 28%, a greater than 60% relative increase. There were no changes in home discharge observed at the control sites (about 15% throughout the 16-month study). The increase in home discharge was not associated with an increase in short-term return visits or major complications. 
Author Interviews, Blood Clots, Cancer Research / 17.04.2018

MedicalResearch.com Interview with: Dr. Jens Sundbøll Department of Clinical Epidemiology Aarhus University Hospital Aarhus, Denmark MedicalResearch.com: What is the background for this study? What are the main findings? Response: The incidence of acute peripheral arterial occlusion is approximately 1.5 cases per 10,000 person-years. In comparison, the incidence rate of deep venous thrombosis is about 5-10cases per 10,000 person-years. It has been established previously that deep venous thrombosis in the lower limb and pulmonary embolism may be presenting symptoms of cancer and is associated with a poor cancer prognosis. However, whether arterial thromboembolism of the lower limb also can represent prodromal symptoms of occult cancer and worsen cancer prognosis has never been investigated.
Author Interviews, Blood Clots, CHEST, OBGYNE, Surgical Research, Thromboembolism / 27.09.2016

MedicalResearch.com Interview with: Marc Blondon, MD Division of Angiology and Hemostasis, Department of Specialties of Medicine, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland Seattle Epidemiologic Research and Information Center, Department of Veterans Affairs Office of Research and Development, Seattle, WA MedicalResearch.com: What is the background for this study? What are the main findings? Response: Venous thromboembolism, a condition including deep vein thrombosis (blood clots) and pulmonary embolism, is more common in older than younger patients. However, pregnancy and particularly the postpartum period are times at greater risk of blood clots in women. It is important to understand the risk and the risk factors for thrombosis in the postpartum period to guide the use of preventive measures such as heparin, an anticoagulant treatment, or leg compression devices. Our study summarizes the evidence on the link between C-sections and blood clots from the past 35 years. Our meta-analysis demonstrates that:
  • C-section carries a 4-fold increased risk of blood clots in the postpartum period, compared with vaginal deliveries ;
  • that this risk is most prominent but not restricted to emergency C-section ;
  • and that women who undergo elective C-section are also at higher risk than women who have a vaginal delivery.
  • Importantly, we estimated an absolute risk of blood clots after a C-section of 2-4 per 1000 pregnancies: on average, 3 out of 1000 women after C-section will develop a blood clot.
Author Interviews, Blood Clots, Endocrinology, Hormone Therapy, Pharmacology / 07.01.2016

[caption id="attachment_20473" align="alignleft" width="160"]Ida Martinelli MD, PhD A Bianchi Bonomi Hemophilia and Thrombosis Center Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milan, Italy Dr. Martinelli[/caption] MedicalResearch.com Interview with: Ida Martinelli MD, PhD A Bianchi Bonomi Hemophilia and Thrombosis Center Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milan, Italy  Medical Research: What is the background for this study? What are the main findings? Dr. Martinelli: Hormonal therapies are associated with an increased risk of venous thromboembolism. Patients with acute deep-vein thrombosis or pulmonary embolism require anticoagulation, but women of childbearing potential require also an adequate contraception, as oral anticoagulants cross the placenta potentially leading to embryopathy or fetal bleeding. This study was aimed to evaluate the safety of hormonal therapies together with anticoagulant therapies in terms of recurrent venous thrombosis and uterine bleeding. We demonstrated for the first time that women who take oral anticoagulants can safely use hormonal therapies, as their risk of recurrent venous thromboembolism or uterine bleeding is not increased.
Author Interviews, Blood Clots, Orthopedics, PLoS / 16.11.2015

MedicalResearch.com Interview with: Banne Nemeth, MD and  Suzanne C. Cannegieter MD PhD Leiden University Medical Center The Einthoven Laboratory for Experimental Vascular Medicine Clinical Department of Epidemiology and Orthopedic Surgery Medical Research: What is the background for this study? What are the main findings? Dr. Nemeth: Clinicians cannot currently accurately predict who will develop venous thrombosis, but it would be very helpful to be able to identify individuals at high risk for venous thrombosis because the condition can be prevented by giving anticoagulants before a clot forms (thromboprophylaxis). The ability to predict venous thrombosis would be particularly useful in patients who have had a lower limb immobilized in a cast after, for example, breaking a bone. These patients have an increased risk of venous thrombosis compared to patients without cast immobilization. We developed and validated a prediction model to identify patients with plaster cast of the lower extremity who are at high risk to develop venous thrombosis. A clinical risk score named, L-TRIP(cast) score (Leiden Thrombosis Risk Prediction for patients with cast immobilization score), was developed containing 14 clinical risk factors such as age, sex, BMI, use of oral contraceptives and location of plaster cast. Patients that score 9 points or higher are classified as being at high risk for venous thrombosis. Clinicians may decide to prescribe thromboprophylaxis therapy for these patients.
AHA Journals, Author Interviews, Blood Clots, Brigham & Women's - Harvard, Medical Imaging / 17.09.2015

Peter Caravan, PhD Co-Director, Institute for Innovation in Imaging (I3) Martinos Center for Biomedical Imaging Massachusetts General Hospital Associate Professor of Radiology Harvard Medical SchoolMedicalResearch.com Interview with: Peter Caravan, PhD Co-Director, Institute for Innovation in Imaging (I3) Martinos Center for Biomedical Imaging Massachusetts General Hospital Associate Professor of Radiology Harvard Medical School Medical Research: What is the background for this study? What are the main findings? Dr. Caravan: The motivation for this work was to develop a technique that would allow the detection of thrombus (clot) anywhere in the body after injection of a molecular probe called 64Cu-FBP8.  Current techniques for thrombus detection are limited to specific vascular territories.  In instances where the location of the thrombus is unknown or if there is suspicion of multiple thrombi, then multiple imaging tests must be performed.  We sought to develop a test that could be used to find clots anywhere:  brain, thorax, abdomen, legs and in arteries, veins, or the cardiac chambers.  In addition to whole body thrombus detection, we sought a technique that could address some of the limitations with current thrombus imaging techniques.  For example computed tomography (CT), which is used to detect pulmonary emboli, requires a contrast agent that cannot be used in patients with poor kidney function.  Transesophageal echocardiography used to identify thrombus in the chambers of the heart requires that the patient be sedated. Our approach is to use a small peptide that recognizes the protein fibrin, which is a key component of blood clots.  We tagged the peptide with an isotope of copper, Cu-64, that allows the peptide to be detected by positron emission tomography (PET). 64Cu-FBP8 binds specifically to fibrin but not to other proteins in the blood and this means that the uptake in the clot is high while background signal is very low.  We combined PET imaging which finds the clot with CT imaging or magnetic resonance imaging (MRI).  By overlaying the PET image with the CT or MRI image, we could precisely localize the clot within the We were interested to see if the age of the clot impacted our ability to detect it.  We imaged animals with a total of 42 arterial or venous clots and then the images were analyzed by two reviewers who had no prior knowledge of the location of the clot.  Overall the accuracy was 98% for detection. Another key finding was that the uptake of 64Cu-FBP8 strongly correlated with the amount of fibrin in the clot and that younger, fresher clots had more fibrin than older clots.  This could be very useful in distinguishing newer clots which may be the source of cardiovascular events from older, clots that may pose less risk. We also showed using combined PET-MRI that we could detect multiple blood clots in the animal in a single whole body scan.  The procedure involves a single intravenous administration of 64Cu-FBP8 and clots in the deep veins of the legs or in the carotid arteries were readily detected.
Blood Clots, General Medicine, UCSD / 19.05.2014

MedicalResearch.com Interview withTimothy Fernandes, M.D., M.P.H. University of California, San Diego - La Jolla, CA Timothy Fernandes, M.D., M.P.H. University of California, San Diego La Jolla, CA MedicalResearch: What are the main findings of this study? Dr. Fernandes: The fibrinopeptides are cleaved off of fibrinogen by thrombin during the generation of a new clot. These small molecules are excreted into the urine and we have developed a urine assay to measure the level of FPB. We examined the performance of urine FPB as a screening test for acute pulmonary embolism, blood clots that travel to the lungs. The study group consisted of 344 patients: 61 (18%) with pulmonary embolism and 283 (83%) without. At a threshold of 2.5 ng/ml, urine FPB demonstrated sensitivity of 75.4% (95% CI: 62.4-85.2%), specificity of 28.9% (95% CI: 23.8-34.7%), and negative likelihood ratio of 0.18 (0.11-0.29), weighted by prevalence in the sample population. However, the thresholds of 5 ng/ml and 7.5 ng/ml had sensitivities of only 55.7% (95% CI: 42.5-68.2%), and 42.6% (30.3-55.9%), respectively. The urine fibrinopeptide B assay at a cut-off of 2.5 ng/ml had a sensitivity of 75.4% for detecting pulmonary embolism. For diagnosis of PE, this sensitivity is comparable to previously published values for the first generation plasma latex and whole blood D-dimer assays (not as well and the D dimer ELISA assay).
Author Interviews, Blood Clots, CHEST / 18.05.2014

Scott C. Woller, MD Co-Director Thrombosis Program Intermountain Medical Center Associate Professor of Internal Medicine University of Utah School of Medicine Murray, UT 84157-7000MedicalResearch.com Interview with Scott C. Woller, MD Co-Director Thrombosis Program Intermountain Medical Center Associate Professor of Internal Medicine University of Utah School of Medicine Murray, UT 84157-7000 Dr. Woller: By way of background, D-dimer, a simple blood test that is used to investigate the diagnosis of suspected pulmonary embolism (PE), and it increases with age.  Recent research suggests that the use of an age-adjusted d-dimer threshold may improve diagnostic efficiency without compromising safety. We wished to assess the safety of using an age-adjusted d-dimer threshold in the work-up of patients with suspected pulmonary embolism. MedicalResearch:  What are the main findings of the study? Dr. Woller: In this retrospective cohort study we identified 923 patients age > 50 years who presented to our emergency department with suspected pulmonary embolism, and had their pretest probability of PE calculated along with a d-dimer performed. All patients underwent computed tomography pulmonary angiography (CTPA). We observed that among patients unlikely to have PE, adoption of an age-adjusted D-dimer cut-off (compared with a conventional D-dimer cut-off) reduced the need for CTPA in an additional 18.3% of patients, and was associated with a low 90-day rate of failure to diagnose PE.
Author Interviews, Blood Clots, Case Western, Cleveland Clinic, JAMA / 24.11.2013

Ilke Sipahi, MD Department of Cardiology Acibadem University Medical School, Istanbul, Turkey Harrington Heart and Vascular Institute, University Hospitals Case Medical Cente  Case Western Reserve University School of Medicine, Cleveland, OhioMedicalResearch.com Interview with: Ilke Sipahi, MD Department of Cardiology Acibadem University Medical School, Istanbul, Turkey Harrington Heart and Vascular Institute, University Hospitals Case Medical Cente, Case Western Reserve University School of Medicine, Cleveland, Ohio MedicalResearch.com: Were you surprised at the extreme difference between these 2 analyses? Answer: I was surprised. However, it is not unusual to find completely contradictory results in medical studies. I was more surprised at the fact that FDA paid more attention to it administrative observational dataset rather than the huge large randomized clinical trials, all showing excess GI bleeds with dabigatran (Pradaxa). Anyone who is even slightly familiar with the medical literature knows that randomized trials are the gold standard in medical studies.
Author Interviews, Blood Clots, Kidney Disease / 24.11.2013

Frits R. Rosendaal PhD Department of Clinical Epidemiology Leiden University Medical Center, Leiden, The NetherlandsMedicalResearch.com Interview with: Frits R. Rosendaal PhD Department of Clinical Epidemiology Leiden University Medical Center, Leiden, The Netherlands MedicalResearch.com: What are the main findings of the study? Answer: In our study, we  found that moderately to severely decreased kidney function was associated with a 2.6-fold (95%CI 2.0-3.5) increased risk of venous thrombosis as compared with normal kidney function. Several hemostatic factors showed a procoagulant shift with decreasing kidney function, most notably factor VIII and von Willebrand factor. We showed that the increased risk of venous thrombosis in chronic kidney disease could not be explained by confounding factors such as body mass index, diabetes, hospitalization, or corticosteroid use. However, we found that factor VIII and von Willebrand factor fully explained the increased risk of venous thrombosis associated with impaired kidney function.
Author Interviews, Blood Clots, BMJ / 24.11.2013

MedicalResearch.com Interview with: Alyshah Abdul Sultan, doctorate student Division of Epidemiology and Public Health, University of Nottingham, Clinical Sciences Building Phase 2, City Hospital, Nottingham NG5 1PB, UK MedicalResearch.com: What are the main findings of the study? Answer: Overall, we found that hospitalisation during pregnancy was associated with an excess risk of 16.6 cases per 1,000 person-years compared with time outside hospital (17.5-fold increase in risk). There was also an excess risk of 5.8 cases per 1,000 person years in the 28 days after discharge with VTE events more likely to occur in the third trimester of pregnancy and in women aged 35 years and over.
Author Interviews, Blood Clots / 13.11.2013

MedicalResearch.com Interview with: Matteo Nicola Dario Di Minno, MD Dept. of Clinical Medicine and Surgery Regional Reference Center for Coagulation Disorders Federico II University, Naples, ItalyMedicalResearch.com: Matteo Nicola Dario Di Minno, MD Dept. of Clinical Medicine and Surgery Regional Reference Center for Coagulation Disorders Federico II University, Naples, Italy   MedicalResearch.com: What are the main findings of the study?
 Answer: In our study, patients with unprovoked VTE treated for a definite time with oral anticoagulants (ie, 3–12 months) had annual recurrence rates >5% in the presence of both overt and mild antithrombin deficiency and <5% with normal antithrombin levels, with these differences being statistically significant. Although these findings should be confirmed in further studies, a life-long oral anticoagulation might be considered in patients with unprovoked VTE.
Author Interviews, Blood Clots, Gender Differences / 01.11.2013

MedicalResearch.com Interview with: Dr. W.M. Lijfering, MD, PhD Department of Clinical Epidemiology, C7-P-89 Leiden University Medical Center PO Box 9600 2300 RC LeidenDr. W.M. Lijfering, MD, PhD Department of Clinical Epidemiology, C7-P-89 Leiden University Medical Center PO Box 9600 2300 RC Leiden   MedicalResearch.com: What are the main findings of the study? Dr. Lijfering: In this study we found that the risk of a first venous thrombosis* is two-fold higher in men than in women once female reproductive risk factors for venous thrombosis are taken into account (odds ratio 1.9, 95% CI 1.7-2.2). These results were found in all age categories (18-70 years) and were not affected by adjustment for body mass index and smoking, or by excluding participants with malignancy.
Author Interviews, Blood Clots, JAMA / 13.10.2013

Mila Ju, MD Resident, Division of Vascular Surgery Northwestern University 676 N. Saint Clair St., Ste 650 Chicago, IL  60611MedicalResearch.com Interview with: Mila Ju, MD Resident, Division of Vascular Surgery Northwestern University 676 N. Saint Clair St., Ste 650 Chicago, IL  60611 MedicalResearch.com: What are the main findings of the study? Dr. Ju: By using combined data from Hospital Compare, American Hospital Association, and Medicare claims databases, we found that better hospital venous thromboembolism (VTE) prophylaxis adherence rates were weakly associated with worse risk-adjusted VTE event rates. Moreover, hospitals with higher intensity of detecting VTE with imaging studies (such as venous duplex, chest computer tomography, etc.) had more VTE events (13.5 in highest VTE imaging quartile vs 5.0 in lowest VTE imaging quartile) per 1000 discharges. Our study suggests that VTE rates might be influenced by surveillance bias and not reflecting the true quality of care provided by the hospitals.