M. J. H. A. Kruip

Potential of an age adjusted D-dimer cut-off value to improve the exclusion of pulmonary embolism in older patients: a retrospective analysis of three large cohorts.

Objectives In older patients, the the D-dimer test for pulmonary embolism has reduced specificity and is therefore less useful. In this study a new, age dependent cut-off value for the test was devised and its usefulness with older patients assessed. Design Retrospective multicentre cohort study. Setting General and teaching hospitals in Belgium, France, the Netherlands, and Switzerland. Patients 5132 consecutive patients with clinically suspected pulmonary embolism. Intervention Development of a new D-dimer cut-off point in patients aged >50 years in a derivation set (data from two multicentre cohort studies), based on receiver operating characteristics (ROC) curves. This cut-off value was then validated with two independent validation datasets. Main outcome measures The proportion of patients in the validation cohorts with a negative D-dimer test, the proportion in whom pulmonary embolism could be excluded, and the false negative rates. Results The new D-dimer cut-off value was defined as (patient’s age×10) μg/l in patients aged >50. In 1331 patients in the derivation set with an “unlikely” score from clinical probability assessment, pulmonary embolism could be excluded in 42% with the new cut-off value versus 36% with the old cut-off value (<500 μg/l). In the two validation sets, the increase in the proportion of patients with a D-dimer below the new cut-off value compared with the old value was 5% and 6%. This absolute increase was largest among patients aged >70 years, ranging from 13% to 16% in the three datasets. The failure rates (all ages) were 0.2% (95% CI 0% to 1.0%) in the derivation set and 0.6% (0.3% to 1.3%) and 0.3% (0.1% to 1.1%) in the two validation sets. Conclusions The age adjusted D-dimer cut-off point, combined with clinical probability, greatly increased the proportion of older patients in whom pulmonary embolism could be safely excluded.

Outpatient treatment in patients with acute pulmonary embolism: the Hestia Study

Summary.  Background: Traditionally, patients with pulmonary embolism (PE) are initially treated in the hospital with low molecular weight heparin (LMWH). The results of a few small non‐randomized studies suggest that, in selected patients with proven PE, outpatient treatment is potentially feasible and safe. Objective: To evaluate the efficacy and safety of outpatient treatment according to predefined criteria in patients with acute PE. Patients and Methods: A prospective cohort study of patients with objectively proven acute PE was conducted in 12 hospitals in The Netherlands between 2008 and 2010. Patients with acute PE were triaged with the predefined criteria for eligibility for outpatient treatment, with LMWH (nadroparin) followed by vitamin K antagonists. All patients eligible for outpatient treatment were sent home either immediately or within 24 h after PE was objectively diagnosed. Outpatient treatment was evaluated with respect to recurrent venous thromboembolism (VTE), including PE or deep vein thrombosis (DVT), major hemorrhage and total mortality during 3 months of follow‐up. Results: Of 297 included patients, who all completed the follow‐up, six (2.0%; 95% confidence interval [CI] 0.8–4.3) had recurrent VTE (five PE [1.7%] and one DVT [0.3%]). Three patients (1.0%, 95% CI 0.2–2.9) died during the 3 months of follow‐up, none of fatal PE. Two patients had a major bleeding event, one of which was fatal intracranial bleeding (0.7%, 95% CI 0.08–2.4). Conclusion: Patients with PE selected for outpatient treatment with predefined criteria can be treated with anticoagulants on an outpatient basis. (Dutch Trial Register No 1319; http://www.trialregister.nl/trialreg/index.asp).

Further validation and simplification of the Wells clinical decision rule in pulmonary embolism

The Wells rule is a widely applied clinical decision rule in the diagnostic work-up of patients with suspected pulmonary embolism (PE). The objective of this study was to replicate, validate and possibly simplify this rule. We used data collected in 3,306 consecutive patients with clinically suspected PE to recalculate the odds ratios for the variables in the rule, to calculate the proportion of patients with PE in the probability categories, the area under the ROC curve and the incidence of venous thromboembolism during follow-up. We compared these measures with those for a modified and a simplified version of the decision rule. In the replication, the odds ratios in the logistic regression model were found to be lower for each of the seven individual variables (p = 0.02) but the proportion of patients with PE in the probability categories in our study group were comparable to those in the original derivation and validation groups. The area under the ROC of the original, modified and simplified decision rule was similar: 0.74 (p = 0.99; p = 0.07). The venous thromboembolism incidence at three months in the group of patients with a Wells score < or = 4 and a normal D-dimer was 0.5%, versus 0.3% with a modified rule and 0.5% with a simplified rule. The proportion of patients safely excluded for PE was 32%, versus 31% and 30%, respectively. This study further validates the diagnostic utility of the Wells rule and indicates that the scoring system can be simplified to one point for each variable.

Risk profile and clinical outcome of symptomatic subsegmental acute pulmonary embolism

The clinical significance of subsegmental pulmonary embolism (SSPE) remains to be determined. This study aimed to investigate whether SSPE forms a distinct subset of thromboembolic disease compared with more proximally located pulmonary embolism (PE). We analyzed 3728 consecutive patients with clinically suspected PE. SSPE patients were contrasted to patients with more proximal PE and to patients in whom suspected PE was ruled out, in regards of the prevalence of thromboembolic risk factors and the 3-month risks of recurrent venous thromboembolism (VTE) and mortality. PE was confirmed in 748 patients, of whom 116 (16%) had SSPE; PE was ruled out in 2980 patients. No differences were seen in the prevalence of VTE risk factors, the 3-month risk of recurrent VTE (3.6% vs 2.5%; P = .42), and mortality (10.7% vs 6.5%; P = .17) between patients with SSPE and those with more proximal PE. When compared with patients without PE, aged >60 years, recent surgery, estrogen use, and male gender were found to be independent predictors for SSPE, and patients with SSPE were at an increased risk of VTE during follow-up (hazard ratio: 3.8; 95% CI: 1.3-11.1). This study indicates that patients with SSPE mimic those with more proximally located PE in regards to their risk profile and clinical outcome.

Accuracy of clinical decision rule, D‐dimer and spiral computed tomography in patients with malignancy, previous venous thromboembolism, COPD or heart failure and in older patients with suspected pulmonary embolism

Summary.  Background: The diagnostic work‐up of patients with suspected pulmonary embolism (PE) has been optimized and simplified by the use of clinical decision rules (CDR), D‐dimer (DD) testing and spiral computed tomography (s‐CT). Whether this strategy is equally safe and efficient in specific subgroups of patients is evaluated in this study. Methods: A diagnostic strategy including a CDR, DD test and s‐CT was evaluated in patients with malignancy, previous venous thromboembolism (VTE), chronic obstructive pulmonary disease or heart failure and in older patients. PE was ruled out by either an unlikely CDR and a normal DD or a s‐CT negative for PE. The safety of these tests was assessed by the 3‐month incidence rate of symptomatic VTE in those without PE at baseline. The efficiency was evaluated by calculating the numbers needed to test for the different subgroups. Results: The venous thromboembolic incidence rate after the combination of an unlikely CDR and a normal DD varied from 0% (95% CI: 0–7.9%) in the 482 patients older than 75 years of age to 2% (95% CI: 0.05–10.9%) in the 474 patients with a malignancy. For s‐CT these incidences varied from 0.3% to 1.8%. The number needed to test in order to rule out one patient from PE with the studied strategy was highest in cancer patients and in the elderly patients (approximately 10). Conclusion: It appears to be safe to rule out PE by either the combination of an unlikely CDR and a normal DD or by a negative s‐CT in various subgroups of patients with suspected PE. However, the clinical usefulness of the CDR in combination with the DD as the initial step in the diagnostic process varied among these patient groups.

Factor VIII deficiency does not protect against atherosclerosis

See also Makris M, van Veen JJ. Reduced cardiovascular mortality in hemophilia despite normal atherosclerotic load. This issue, pp 20–2; Zwiers M, Lefrandt JD, Mulder DJ, Smit AJ, Gans ROB, Vliegenthart R, Brands‐Nijenhuis AVM, Kluin‐Nelemans JC, Meijer K. Coronary artery calcification score and carotid intima–media thickness in patients with hemophilia. This issue, pp 23–9.

A simple diagnostic strategy in hospitalized patients with clinically suspected pulmonary embolism

Objectives.  Diagnostic strategies in patients with suspected pulmonary embolism have been extensively studied in outpatients; their value in hospitalized patients has not been well established. Our aim was to determine the safety and clinical utility of a simple diagnostic strategy in hospitalized patients with suspected pulmonary embolism.

Comparison of two methods for selection of out of hospital treatment in patients with acute pulmonary embolism

The aim of this study is to compare the performance of two clinical decision rules to select patients with acute pulmonary embolism (PE) for outpatient treatment: the Hestia criteria and the simplified Pulmonary Embolism Severity Index (sPESI). From 2008 to 2010, 468 patients with PE were triaged with the Hestia criteria for outpatient treatment: 247 PE patients were treated at home and 221 were treated as inpatients. The outcome of interest was all-cause 30-day mortality. In a post-hoc fashion, the sPESI items were scored and patients were classified according to the sPESI in low and high risk groups. Of the 247 patients treated at home, 189 (77%) patients were classified as low risk according to the sPESI and 58 patients (23%) as high risk. In total, 11 patients died during the first month; two patients treated at home and nine patients treated in-hospital. None of the patients treated at home died of fatal PE. Both the Hestia criteria and sPESI selected >50% of patients as low risk, with good sensitivity and negative predictive values for 30-day mortality: 82% and 99% for the Hestia criteria and 91% and 100% for the sPESI, respectively. The Hestia criteria and the sPESI classified different patients eligible for outpatient treatment, with similar low risks for 30-day mortality. This study suggests that the Hestia criteria may identify a proportion of high risk sPESI patiennts who can be safely treated at home, this however requires further validation.

Hypercoagulability and Hypofibrinolysis and Risk of Deep Vein Thrombosis and Splanchnic Vein Thrombosis Similarities and Differences

In this review, we provide an overview of the risk factors for venous thromboembolism, focusing on hypercoagulability and hypofibrinolysis. In the first part of this review, we discuss the risk factors for commonly occurring venous thrombosis, in particular deep vein thrombosis and pulmonary embolism. In the second part, we provide an overview of the risk factors for the Budd-Chiari syndrome and portal vein thrombosis. These are rare, life-threatening forms of venous thromboembolism located in the splanchnic veins. There are many similarities in the risk profiles of patients with common venous thrombosis and splanchnic vein thrombosis. Inherited thrombophilia and hypofibrinolysis increase the risk of both common venous thrombosis and splanchnic vein thrombosis. However, there are also apparent differences. Myeloproliferative neoplasms and paroxysmal nocturnal hemoglobinuria have a remarkably high frequency in patients with thrombosis at these unusual sites but are rarely seen in patients with common venous thrombosis. There are also clear differences in the underlying risk factors for Budd-Chiari syndrome and for portal vein thrombosis, suggesting site specificity of thrombosis even within the splanchnic venous system. These clear differences in underlying risk factors provide leads for further research on the site specificity of venous thrombosis and the development of thrombosis at these distinct sites.

E‐learning improves knowledge and practical skills in haemophilia patients on home treatment: a randomized controlled trial

Summary.  Home treatment of haemophilia is currently the standard of care for patients with severe haemophilia. Home treatment increases the responsibility of the patients for their own treatment and care. Therefore, it is of utmost importance to attain a high level of knowledge and practical skills. The aim of our study was to investigate whether or not an educational e‐learning program improves knowledge and skills of adult patients with haemophilia on home treatment. Participants treated at the Haemophilia Treatment Center of the Erasmus University Medical Centre completed a questionnaire to test their knowledge of haemophilia, treatment of bleedings and of complications of treatment and were observed during the intravenous injection of clotting factor concentrate, using a standardized scoring list. Afterwards they were randomized to follow an e‐learning program or no intervention (control group). After 1 month they completed the same questionnaire again and practical skills were scored once more. At baseline, haemophilia patients (n = 30) scored 24 of 48 questions in the questionnaire correctly. Seventy‐five per cent of the items on the practical skills scoring list were performed correctly. One month later, the e‐learning group (n = 16; 36; 18–45) showed a higher level of theoretical knowledge compared to the control group (n = 14; 26; 19–32; P < 0.001). Also practical skills were significantly better in the group that followed the e‐learning program compared to the control group (respectively P = 0.002). Self‐efficacy of 90% vs. 80% the patients with haemophilia was high in all patients. Our study shows that in haemophilia patients with haemophilia, who are on home treatment, knowledge of haemophilia treatment and complications as well as practical skills can be improved by an educational e‐learning program.