BACKGROUND:Apixaban and rivaroxaban are the oral anticoagulants most frequently used to treat acute venous thromboembolism. However, uncertainty remains about the difference in bleeding risk between the two medications. METHODS:In an international trial with a prospective, randomized, open-label, blinded end-point design, we assigned, in a 1:1 ratio, eligible patients with acute symptomatic pulmonary embolism or proximal deep-vein thrombosis to receive apixaban or rivaroxaban for 3 months. Apixaban was given at a dose of 10 mg twice daily for 7 days followed by 5 mg twice daily, and rivaroxaban was given at a dose of 15 mg twice daily for 21 days followed by 20 mg daily. The primary outcome was clinically relevant bleeding, a composite of major bleeding or clinically relevant nonmajor bleeding, as defined according to the International Society on Thrombosis and Haemostasis, during the 3-month trial period. Secondary outcomes included death from any cause. RESULTS:A total of 2760 patients underwent randomization: 1370 to the apixaban group and 1390 to the rivaroxaban group. A primary-outcome event occurred in 44 of 1345 patients (3.3%) in the apixaban group and 96 of 1355 patients (7.1%) in the rivaroxaban group (relative risk, 0.46; 95% confidence interval [CI], 0.33 to 0.65; P<0.001). Death from any cause occurred in 1 patient (0.1%) in the apixaban group and in 4 patients (0.3%) in the rivaroxaban group (relative risk, 0.25; 95% CI, 0.03 to 2.26). Serious adverse events unrelated to bleeding or venous thrombosis occurred in 36 patients (2.7%) in the apixaban group and in 30 patients (2.2%) in the rivaroxaban group. CONCLUSIONS:Among patients with acute venous thromboembolism, the risk of clinically relevant bleeding was significantly lower with apixaban than with rivaroxaban during the 3-month treatment period. (Funded by the Canadian Institutes of Health Research and others; COBRRA ClinicalTrials.gov number, NCT03266783.).

BACKGROUND:Patients with cancer-associated thrombosis (CAT) are treated with full-dose anticoagulation for at least 3 months, but optimal dosing thereafter is unknown.AIM:We explored the feasibility of extended prophylactic-dose low molecular weight heparin (LMWH) treatment following a minimum of 3 months of full-dose LMWH.METHODS:We conducted a multicenter prospective pilot study of patients with CAT who completed at least 3 months of therapeutic-dose LMWH. Patients received 6 months of prophylactic-dose subcutaneous enoxaparin (40 mg once daily). The primary outcome was recurrence of deep vein thrombosis (DVT) or pulmonary embolism (PE), and secondary outcomes included major, clinically relevant non-major (CRNM), and minor bleeding.RESULTS:From August 2016 to May 2019, 52 patients with a mean age of 64.1 years were included. The study was stopped early because of poor recruitment. Breast (23.1%) and colorectal (19.2%) were the most common cancers, and 61.0% had stage IV malignancy. Index CAT consisted of DVT alone in 57.7% of patients and pulmonary embolism (PE) with or without DVT in 42.3%. Patients received a mean of 7.6 months of weight-adjusted LMWH before enrollment. During a mean follow-up of 5.6 months, one patient was diagnosed with recurrent incidental PE (0.0035 events/subject-month). There were no major bleeding events, one CRNM, and one minor bleeding event. Eight (15.4%) patients died; six from cancer and two from respiratory disease unrelated to PE.CONCLUSIONS:These results, in part, provide support for trials of extended reduced-dose anticoagulation for the secondary prevention of CAT. (ClinicalTrials.gov: NCT02752607).

Abstract No clinical prediction model has been specifically developed or validated to identify patients with unprovoked venous thromboembolism (VTE) who are at high risk of major bleeding during extended anticoagulation. In a prospective multinational cohort study of patients with unprovoked VTE receiving extended anticoagulation after completing ≥3 months of initial treatment, we derived a new clinical prediction model using a multivariable Cox regression model based on 22 prespecified candidate predictors for the primary outcome of major bleeding. This model was then compared with modified versions of 5 existing clinical scores. A total of 118 major bleeding events occurred in 2516 patients (annual risk, 1.7%; 95% confidence interval [CI], 1.4-2.1). The incidences of major bleeding events per 100 person-years in high-risk and non–high-risk patients, respectively, were 3.9 (95% CI, 3.0-5.1) and 1.1 (0.8-1.4) using the newly derived creatinine, hemoglobin, age, and use of antiplatelet agent (CHAP) model; 3.3 (2.6-4.1) and 1.0 (0.7-1.3) using modified ACCP score, 5.3 (0.6-19.2) and 1.7 (1.4-2.0) using modified RIETE score, 3.1 (2.3-3.9) and 1.1 (0.9-1.5) using modified VTE-BLEED score, 5.2 (3.3-7.8) and 1.5 (1.2-1.8) using modified HAS-BLED score, and 4.8 (1.3-12.4) and 1.7 (1.4-2.0) using modified outpatient bleeding index score. Modified versions of the ACCP, VTE-BLEED, and HAS-BLED scores help identify patients with unprovoked VTE who are at high risk of major bleeding and should be considered for discontinuation of anticoagulation after 3 to 6 months of initial treatment. The CHAP model may further improve estimation of bleeding risk by using continuous predictor variables, but external validation is required before its implementation in clinical practice.

Introduction The risk of recurrent venous thromboembolism (VTE) after combined oral contraceptive (COC) use is variably reported. We assessed the long-term risk of recurrent VTE in women on COC at the time of a first VTE, in comparison to women without COC use. Our secondary aim assessed the impact of COC use on the recurrent VTE risk in high-risk and low-risk hyperpigmentation, edema, or redness in either leg; D-dimer level >= 250 mu g/L; obesity with body mass index >= 30; or older age, >= 65 years (HERDOO2) subgroups. Methods The REVERSE cohort study derived the HERDOO2 clinical decision rule to predict recurrent VTE in patients who discontinued anticoagulation after 5-7 months for a first unprovoked VTE. Incidence rates of recurrent VTE among women with and without COC exposure were calculated as the number of recurrent VTE over the number of person-years of follow-up, and Cox proportional hazards model was used to compare risks between groups. Results The risk of recurrent VTE among COC users was 1.1% (95% confidence interval [CI] 0.3-2.9) per patient-year as compared with 3.2% per patient-year (95% CI 2.4-4.3) among nonusers (hazard ratio 0.37; 95% CI 0.1-1.0). Women who were COC users and high risk by HERDOO2 score had a recurrence rate of 3.5% (95% CI 0.4-12.5) compared with 6.1% (95% CI 4.3-8.5) among women who were non-COC users and at high risk by HERDOO2 score (HR 0.6, 95% CI 0.1-2.5). Conclusions Women who were COC users at the time of an otherwise unprovoked VTE event had a lower VTE recurrence rate during long-term follow-up, compared with nonusers. The use of HERDOO2 rule may help identify higher risk women with COC use.

Abstract Objective To determine the efficacy and safety of dalteparin postoperative bridging treatment versus placebo for patients with atrial fibrillation or mechanical heart valves when warfarin is temporarily interrupted for a planned procedure. Design Prospective, double blind, randomised controlled trial. Setting 10 thrombosis research sites in Canada and India between February 2007 and March 2016. Participants 1471 patients aged 18 years or older with atrial fibrillation or mechanical heart valves who required temporary interruption of warfarin for a procedure. Intervention Random assignment to dalteparin (n=821; one patient withdrew consent immediately after randomisation) or placebo (n=650) after the procedure. Main outcome measures Major thromboembolism (stroke, transient ischaemic attack, proximal deep vein thrombosis, pulmonary embolism, myocardial infarction, peripheral embolism, or vascular death) and major bleeding according to the International Society on Thrombosis and Haemostasis criteria within 90 days of the procedure. Results The rate of major thromboembolism within 90 days was 1.2% (eight events in 650 patients) for placebo and 1.0% (eight events in 820 patients) for dalteparin (P=0.64, risk difference −0.3%, 95% confidence interval −1.3 to 0.8). The rate of major bleeding was 2.0% (13 events in 650 patients) for placebo and 1.3% (11 events in 820 patients) for dalteparin (P=0.32, risk difference −0.7, 95% confidence interval −2.0 to 0.7). The results were consistent for the atrial fibrillation and mechanical heart valves groups. Conclusions In patients with atrial fibrillation or mechanical heart valves who had warfarin interrupted for a procedure, no significant benefit was found for postoperative dalteparin bridging to prevent major thromboembolism. Trial registration Clinicaltrials.gov NCT00432796 .

Background After a proximal lower limb deep vein thrombosis (DVT; involving popliteal veins or above), up to 40% of patients develop postthrombotic syndrome (PTS) as assessed by the Villalta scale (VS). Poor initial anticoagulant treatment is a known risk factor for PTS. The risk of developing PTS after isolated distal DVT (infra-popliteal DVT without pulmonary embolism), and the impact of anticoagulant treatment on this risk, are uncertain. Methods Long-term follow-up of CACTUS double-blind trial comparing 6 weeks of s.c. nadroparin (171 IU/kg/d) versus s.c. placebo for a first symptomatic isolated distal DVT. At least 1 year after randomization, patients had a PTS assessment in clinic or by phone using the VS. Results After a median follow-up of 6 years, PTS was present in 30% (n = 54) of the 178 patients who had a PTS assessment. PTS was moderate or severe in 24% (n = 13) of cases. There was no statistically significant difference in prevalence of PTS in the nadroparin versus placebo groups (29% versus 32%, P = .6), except in patients without evidence of primary chronic venous insufficiency (9% versus 24%, P = .04). Rates of venous thromboembolism recurrence during follow-up in the nadroparin and placebo groups were, respectively, 8% (n = 7) and 14% (n = 13; P = .2). Conclusion After a first isolated distal DVT, the risk of PTS is substantial but much lower than that reported after proximal DVT. Anticoagulation with nadroparin doesn't provide any clear benefit to prevent PTS, except in patients without preexisting chronic venous insufficiency. Anticoagulation might be associated with a lower risk of venous thromboembolism recurrence.

Importance Patients with atrial fibrillation (AF) who use a direct oral anticoagulant (DOAC) and request elective surgery or procedure present a common clinical situation yet perioperative management is uncertain. Objective To investigate the safety of a standardized perioperative DOAC management strategy. Design, Setting, and Participants The Perioperative Anticoagulation Use for Surgery Evaluation (PAUSE) cohort study conducted at 23 clinical centers in Canada, the United States, and Europe enrolled and screened patients from August 1, 2014, through July 31, 2018. Participants (n = 3007) had AF; were 18 years of age or older; were long-term users of apixaban, dabigatran etexilate, or rivaroxaban; were scheduled for an elective surgery or procedure; and could adhere to the DOAC therapy interruption protocol. Interventions A simple standardized perioperative DOAC therapy interruption and resumption strategy based on DOAC pharmacokinetic properties, procedure-associated bleeding risk, and creatinine clearance levels. The DOAC regimens were omitted for 1 day before a low-bleeding-risk procedure and 2 days before a high-bleeding-risk procedure. The DOAC regimens were resumed 1 day after a low-bleeding-risk procedure and 2 to 3 days after a high-bleeding-risk procedure. Follow-up of patients occurred for 30 days after the operation. Main Outcomes and Measures Major bleeding and arterial thromboembolism (ischemic stroke, systemic embolism, and transient ischemic attack) and the proportion of patients with an undetectable or minimal residual anticoagulant level (<50 ng/mL) at the time of the procedure. Results The 3007 patients with AF (mean [SD] age of 72.5 [9.39] years; 1988 men [66.1%]) comprised 1257 (41.8%) in the apixaban cohort, 668 (22.2%) in the dabigatran cohort, and 1082 (36.0%) in the rivaroxaban cohort; 1007 patients (33.5%) had a high-bleeding-risk procedure. The 30-day postoperative rate of major bleeding was 1.35% (95% CI, 0%-2.00%) in the apixaban cohort, 0.90% (95% CI, 0%-1.73%) in the dabigatran cohort, and 1.85% (95% CI, 0%-2.65%) in the rivaroxaban cohort. The rate of arterial thromboembolism was 0.16% (95% CI, 0%-0.48%) in the apixaban cohort, 0.60% (95% CI, 0%-1.33%) in the dabigatran cohort, and 0.37% (95% CI, 0%-0.82%) in the rivaroxaban cohort. In patients with a high-bleeding-risk procedure, the rates of major bleeding were 2.96% (95% CI, 0%-4.68%) in the apixaban cohort and 2.95% (95% CI, 0%-4.76%) in the rivaroxaban cohort. Conclusions and Relevance In this study, patients with AF who had DOAC therapy interruption for elective surgery or procedure, a perioperative management strategy without heparin bridging or coagulation function testing was associated with low rates of major bleeding and arterial thromboembolism.

Venous thromboembolism (VTE) is the second leading cause of death in patients with cancer. These patients are at a high risk of VTE recurrence and bleeding during anticoagulant therapy. The International Initiative on Thrombosis and Cancer is an independent academic working group aimed at establishing a global consensus for the treatment and prophylaxis of VTE in patients with cancer. The International Initiative on Thrombosis and Cancer last updated its evidence-based clinical practice guidelines in 2016 with a free, web-based mobile phone application, which was subsequently endorsed by the International Society on Thrombosis and Haemostasis. The 2019 International Initiative on Thrombosis and Cancer clinical practice guidelines, which are based on a systematic review of the literature published up to December, 2018, are presented along with a Grading of Recommendations Assessment Development and Evaluation scale methods, with the support of the French National Cancer Institute. These guidelines were reviewed by an expanded international advisory committee and endorsed by the International Society on Thrombosis and Haemostasis. Results from head-to-head clinical trials that compared direct oral anticoagulant with low-molecular-weight heparin are also summarised, along with new evidence for the treatment and prophylaxis of VTE in patients with cancer.

BACKGROUND Little has been published about the association of venous thromboembolism (VTE) and sarcoma. In this study, we sought to identify clinical features of patients with sarcoma presenting at least one VTE episode. METHODS Our study was a retrospective case-control study of a single-institution database with univariate and multivariate analysis using chi-square and Student's t test. A p value less than .05 was considered significant. RESULTS The overall incidence of VTE in patients with sarcoma was 7.9%. Predictive factors identified by multivariate analysis were metastatic disease and administration of chemotherapy. It was not statistically possible to correlate the risk of VTE with specific sarcoma subtypes, but observations suggested malignant peripheral nerve sheath tumor, osteosarcoma, and liposarcoma as having the highest propension. CONCLUSION VTE is not infrequent in patients with sarcoma. Adoption of common guidelines for cancer-associated thrombosis is recommended.

Essentials Exercise Limitation 1 year after an acute pulmonary embolism is common. Serial imaging after acute pulmonary embolism is not well described and how it affects exercise limitation remains unknown. 1 year after an acute pulmonary embolism chronic changes are common, more so on perfusion lung scanning than CT pulmonary angiography, but imaging findings did not predict exercise limitation.

In this issue of Blood, Amin et al provide data showing early compression therapy post–venous thromboembolism (VTE) to be effective in reducing the incidence of postthrombotic syndrome (PTS) by achieving reduced residual vein obstruction (RVO) on follow-up ultrasound.1

Background: The optimal duration of oral anticoagulant therapy after a first, unprovoked venous thromboembolism is controversial due to tightly balanced risks and benefits of indefinite anticoagulation. Risk stratification tools may assist in decision making. Objectives: We sought to determine the relationship between residual pulmonary embolism assessed by baseline ventilation-perfusion scan after completion of 5-7 months of oral anticoagulant therapy and the risk of recurrent venous thromboembolism in patients with the first episode of unprovoked pulmonary embolism. Methods: We conducted a multicentre prospective cohort study of participants with a first, unprovoked venous thromboembolism enrolled after the completion of 5-7 months of oral anticoagulation therapy. The participants completed a mean 18-month follow-up. Participants with pulmonary embolism had baseline ventilation-perfusion scan before discontinuation of oral anticoagulant therapy and the percentage of vascular obstruction on baseline ventilation-perfusion scan was determined. During follow-up after discontinuation of oral anticoagulant therapy, all episodes of suspected recurrent venous thromboembolism were independently adjudicated with reference to baseline imaging. Measurements and main results: During follow-up, 24 of 239 (10.0%) participants with an index event of isolated pulmonary embolism or pulmonary embolism associated with deep vein thrombosis and central assessment of percentage of vascular obstruction on baseline ventilation-perfusion scan had confirmed recurrent venous thromboembolism. As compared to participants with no residual pulmonary embolism on baseline ventilation-perfusion scan, the hazard ratio for recurrent venous thromboembolism was 2.0 (95% CI 0.5-7.3) for participants with percentage of vascular obstruction of 0.1%-4.9%, 2.1 (95% CI 0.5-7.8) for participants with percentage vascular obstruction of 5.0%-9.9% and 5.3 (95% CI 1.8-15.4) for participants with percentage vascular obstruction greater than or equal to 10%. Conclusions: Residual pulmonary embolism assessed by pulmonary vascular obstruction on baseline ventilation-perfusion performed after 5-7 months of oral anticoagulant therapy for the first episode of unprovoked pulmonary embolism was associated with a statistically significant higher risk of subsequent recurrent venous thromboembolism. Percentage of pulmonary vascular obstruction assessment by ventilation-perfusion scans maybe a useful tool to help guide the duration of oral anticoagulant therapy after a first unprovoked pulmonary embolism.

Abstract Background It remains uncertain if patients with atrial fibrillation or mechanical heart valves requiring interruption of warfarin for procedures benefit from post-procedure anticoagulant bridging therapy. Methods In order to determine the efficacy and safety of postoperative LMWH bridging, we conducted a multicenter randomized double-blind controlled trial of patients with atrial fibrillation or a mechanical heart valve who require interruption of warfarin for a planned procedure. We excluded patients with active bleeding within 30 days, platelet count <100 x10⁹/L, spinal, cardiac or neurosurgery, life expectancy <3months, creatinine clearance <30ml/min, multiple mechanical valves or a Starr-Edwards valve, mechanical valve with history of stroke or TIA, or a history of heparin induced thrombocytopenia. The last dose of warfarin was given 6 days prior to the procedure. All patients received pre-procedure bridging therapy with dalteparin 200 IU per kilogram (max 18,000 IU) subcutaneously in the morning day-3 and day-2 then dalteparin 100 IU per kilogram (max 18,000 IU) subcutaneously 24 hours pre-procedure. Warfarin was resumed in the evening of the procedure at twice the usual dose for the first two days and then titrated according to INR. After the procedure (same day or next day), when hemostasis had been achieved, patients were randomized to receive dalteparin or placebo for at least 4 days and until the INR was greater than 1.9. Randomization was stratified by presence of a mechanical valve, by the post-procedure risk for major bleeding, and by centre. For patients at high risk for post-procedure major bleeding, dalteparin or placebo was administered at a fixed daily dose of 5000 IU. For patients at low risk for post-procedure major bleeding, dalteparin or placebo was administered at a daily dose of 200 IU per kilogram (max 18,000 IU). The primary analysis was a comparison of the proportion of patients who had major thromboembolism (stroke, proximal DVT, PE, MI, peripheral embolism) over 90 days by Chi-squared test according to the intention to treat principle. Secondary outcomes were major bleeding, all cause mortality and a composite outcome of major thromboembolism and major bleeding. Results Starting in October 2006 we randomized a total of 1471 patients of whom 1167 had atrial fibrillation (without mechanical heart valves) and 304 had mechanical valves (99 also had atrial fibrillation). Last follow up was completed in May 2016. Baseline characteristics were similar between the LMWH and the placebo groups (see Table 1). Due to a randomization program system error at two centres more atrial fibrillation patients were randomized to dalteparin rather than to placebo. Major thromboembolism occurred in 6/820 (0.71%) dalteparin patients and 7/650 (1.11%) placebo patients. Major post-procedure bleeding occurred in 12 (1.46%) dalteparin patients and 16 (2.46%) placebo patients. Findings were similar in patients with atrial fibrillation alone and in patients with mechanical heart valves (with or without atrial fibrillation) (Table 2). Conclusions In patients with atrial fibrillation and/or mechanical heart valves who had warfarin interrupted for a procedure there was no benefit from post-procedure LMWH bridging. Disclosures Kovacs: Bayer: Research Funding; Daiichi Sankyo Pharma Development: Research Funding. Wells:Janssen: Honoraria; Sanofi: Honoraria; BMS: Honoraria, Research Funding; Bayer: Honoraria. Schulman:Boehringer-Ingelheim: Honoraria, Research Funding; Daiichi-Sankyo: Honoraria; Sanofi: Honoraria; Bayer: Honoraria.

Background Management of venous thromboembolism (VTE), encompassing both deep vein thrombosis (DVT) and pulmonary embolism (PE), varies worldwide. Methods The Global Anticoagulant Registry in the FIELD - Venous Thromboembolism (GARFIELD-VTE) is a prospective, observational study of 10,685 patients with objectively diagnosed VTE recruited from May 2014 to January 2017 at 417 sites in 28 countries. All patients are followed for at least 3 years. We describe the baseline characteristics of the study population and their management within 30 days of diagnosis. Results The median age was 60.2 years; 50.4% were male; 61.7% had DVT and 38.3% had PE +/- DVT; and 32.3% were obese (body mass index >= 30 kg/m(2)). The most common risk factors were surgery (12.5%), hospitalization (12.0%) and trauma to the lower limbs (7.8%). At the time of VTE diagnosis, 10.1% had active cancer and 5.7% were chronically immobilized. Treatment for VTE was anticoagulant (AC) therapy alone in 90.9% of patients; 5.1% received thrombolytic and/or surgical/mechanical therapy +/- AC and 4.0% received no therapy. Pre-diagnosis, 12.8% received AC therapy alone and 0.2% received thrombolytic and/or surgical/mechanical therapy +/- AC. After diagnosis, parenteral AC therapy alone was administered in 17.6% of patients, and it was followed by a direct oral AC (DOAC) in 16.4% or a vitamin K antagonist (VKA) in 26.8%. DOACs alone were prescribed to 32.3% of patients, while 5.9% received VKA alone. Conclusion The initial findings from this global registry highlight the heterogeneity in characteristics and management of VTE patients. Prospective follow-up will reveal the impact of this heterogeneity on outcomes.

Background The perioperative management of patients who take a direct oral anticoagulant (DOAC) for atrial fibrillation and require treatment interruption for an elective surgery/procedure is a common clinical scenario for which best practices are uncertain. The Perioperative Anticoagulant Use for Surgery Evaluation (PAUSE) study is designed to address this unmet clinical need. We discuss the rationale for the PAUSE design and analysis plan as well as the rationale supporting the perioperative DOAC protocol. Methods PAUSE is a prospective study with three parallel cohorts, one for each DOAC, to assess a standardized but patient-specific perioperative management protocol for DOAC-treated patients with atrial fibrillation. The perioperative protocol accounts for DOAC type, patient's renal function and surgery/procedure-related bleeding risk. The primary study aim is to demonstrate the safety of the PAUSE protocol for the perioperative management of each DOAC. The secondary aim is to determine the effect of the pre-procedure interruption on residual anticoagulation when measured by the dilute thrombin time for dabigatran and anti-factor Xa levels for rivaroxaban and apixaban. The study hypothesis is that the perioperative management protocol for each DOAC is safe for patient care, defined by expected risks for major bleeding of 1% (80% power to exclude 2%), and for arterial thromboembolism of 0.5% (80% power to exclude 1.5%) in each DOAC group. Conclusion The PAUSE study has the potential to establish a standard-of-care approach for the perioperative management of DOAC-treated patients. The PAUSE management protocol is designed to be easily applied in clinical practice, as it is standardized and also patient specific.

Pulmonary embolism (PE) is the most serious form of venous thromboembolism (VTE). While the incidence of PE has increased over time, its case fatality has declined, with estimates as low as 1.8% reported in the literature [1]. Indeed, hemodynamically stable PE patients are increasingly successfully treated as out-patients [2]. Despite improved diagnosis and treatment of PE, a subset of patients develops long-term sequelae such as chronic thromboembolic pulmonary hypertension [3] or more frequently, exercise limitation [4].

BACKGROUND: We aimed to determine the frequency and predictors of exercise limitation after pulmonary embolism (PE) and to assess its association with health-related quality of life (HRQoL) and dyspnea.METHODS: One hundred patients with acute PE were recruited at five Canadian hospitals from 2010 to 2013. Cardiopulmonary exercise testing (CPET) was performed at 1 and 12 months. Quality of life (QoL), dyspnea, 6-min walk distance (6MWD), residual clot burden (perfusion scan, CT pulmonary angiography), cardiac function (echocardiography), and pulmonary function tests (PFTs) were measured during follow-up. The prespecified primary outcome was percent predicted peak oxygen uptake (Vo(2) peak) < 80% at 1-year CPET.RESULTS: At 1 year, 40 of 86 patients (46.5%) had percent predicted Vo2 peak < 80% on CPET, which was associated with significantly worse generic health-related QoL (HRQoL), PE-specific HRQoL and dyspnea scores, and significantly reduced 6MWD at 1 year. Predictors of the primary outcome included male sex (relative risk [RR], 3.2; 95% CI, 1.3-8.1), age (RR, 0.98; 95% CI, 0.96-0.99 per 1-year age increase), BMI (RR 1.1; 95% CI, 1.01-1.2 per 1 kg/m(2) BMI increase), and smoking history (RR, 1.8; 95% CI, 1.1-2.9), as well as percent predicted Vo2 peak < 80% on CPET at 1 month (RR, 3.8; 95% CI, 1.9-7.2), and 6MWD at 1 month (RR, 0.82; 95% CI, 0.7-0.9 per 30-m increased walking distance). Baseline or residual clot burden was not associated with the primary outcome. Mean PFT and echocardiographic results (pulmonary artery pressure, right and left ventricular systolic function) at 1 year were similarly within normal limits in both patients with exercise limitations and those without such limitations.CONCLUSIONS: Almost half of patients with PE have exercise limitation at 1 year that adversely influences HRQoL, dyspnea, and walking distance. CPET or 6MWD testing at 1 month may help to identify patients with a higher risk of exercise limitation at 1 year after PE. Based on our results, we believe that the deconditioning that occurs after acute PE could underlie this exercise limitation, but we cannot exclude the fact that this may have been present before PE.

BACKGROUND: We aimed to evaluate health-related quality of life (QOL), dyspnea, and functional exercise capacity during the year following the diagnosis of a first episode of pulmonary embolism.METHODS: This was a prospective multicenter cohort study of 100 patients with acute pulmonary embolism recruited at 5 Canadian hospitals from 2010-2013. We measured the outcomes QOL (by Short-Form Health Survey-36 [SF-36] and Pulmonary Embolism Quality of Life [PEmb-QoL] measures), dyspnea (by the University of California San Diego Shortness of Breath Questionnaire [SOBQ]) and 6-minute walk distance at baseline and 1, 3, 6, and 12 months after acute pulmonary embolism. Computed tomography pulmonary angiography was performed at baseline, echocardiogram was performed within 10 days, and cardiopulmonary exercise testing was performed at 1 and 12 months. Predictors of change in QOL, dyspnea, and 6-minute walk distance were assessed by repeated-measures mixed-effects models analysis.RESULTS: Mean age was 50.0 years; 57% were male and 80% were treated as outpatients. Mean scores for all outcomes improved during 1-year follow-up: from baseline to 12 months, mean SF-36 physical component score improved by 8.8 points, SF-36 mental component score by 5.3 points, PEmb-QoL by -32.1 points, and SOBQ by -16.3 points, and 6-minute walk distance improved by 40 m. Independent predictors of reduced improvement over time were female sex, higher body mass index, and percent-predicted VO2 peak < 80% on 1 month cardiopulmonary exercise test for all outcomes; prior lung disease and higher pulmonary artery systolic pressure on 10-day echocardiogram for the outcomes SF-36 physical component score and dyspnea score; and higher main pulmonary artery diameter on baseline computed tomography pulmonary angiography for the outcome PEmb-QoL score.CONCLUSIONS: On average, QOL, dyspnea, and walking distance improve during the year after pulmonary embolism. However, a number of clinical and physiological predictors of reduced improvement over time were identified, most notably female sex, higher body mass index, and exercise limitation on 1-month cardiopulmonary exercise test. Our results provide new information on patient-relevant prognosis after pulmonary embolism. (C) 2017 Elsevier Inc. All rights reserved.