Residual Pulmonary Vascular Obstruction Research Articles

Impact of reperfusion therapies on clot resolution and long-term outcomes in patients with pulmonary embolism

ObjectiveMajor progress in reperfusion strategies has substantially improved the short-term outcomes of patients with pulmonary embolism (PE), however, up to 50% of patients report persistent dyspnea after acute PE. MethodsA retrospective study of the PE response team registry and included patients with repeat imaging at 3 to 12 months. The primary outcome was to determine the incidence of residual pulmonary vascular obstruction following acute PE. Secondary outcomes included the development of PE recurrence, right ventricular (RV) dysfunction, chronic thromboembolic pulmonary hypertension, readmission, and mortality at 12 months. ResultsA total of 382 patients were included, and 107 patients received reperfusion therapies followed by anticoagulation. Patients who received reperfusion therapies including systemic thrombolysis, catheter-directed thrombolysis, and mechanical thrombectomy presented with a higher vascular obstructive index (47% vs 28%; P < .001) and signs of right heart strain on echocardiogram (81% vs 43%; P < .001) at the time of diagnosis. A higher absolute reduction in vascular obstructive index (45% vs 26%; 95% confidence interval, 14.0-25.6; P < .001), greater improvement in RV function (82% vs 65%; P = .021), and lower 12-month mortality rate (2% vs 7%; P = .038) and readmission rate (33% vs 46%; P = .031) were observed in the reperfusion group. No statistically significant differences were found between groups in the development of chronic thromboembolic pulmonary hypertension (8% vs 5%; P = .488) and PE recurrence (8% vs 6%; P = .646). ConclusionsWe observed a favorable survival and greater improvement in clot resolution and RV function in patients treated with reperfusion therapies.

Residual Pulmonary Vascular Obstruction Following Mechanical Thrombectomy for Submassive Pulmonary Embolism: A Single-Center Analysis

BackgroundResidual pulmonary vascular obstruction (RPVO) following pulmonary embolism (PE) is associated with residual dyspnea, recurrent venous thromboembolism, and chronic thromboembolic pulmonary hypertension. Historically, acute PE treated with anticoagulation alone results in high rates of significant RPVO. Contemporary treatment of submassive PE often involves catheter-based interventions, including mechanical thrombectomy (MT), although their relation to RPVO is not characterized. In this study, we aimed to evaluate the rate of ≥10% RPVO in patients treated with MT. MethodsTwenty consecutive patients with submassive PE in a single center underwent MT and subsequent planar ventilation/perfusion scintigraphy scan at a median of 4 months after thrombectomy. A quantitative perfusion score was calculated for each planar ventilation/perfusion scintigraphy study to provide a % perfusion defect. Complete hemodynamic data were collected during the procedure and Miller score was calculated using prepulmonary and postpulmonary angiography. Echocardiographic data were collected prior to, 24 to 48 hours after, and 30 days after the procedure. ResultsFour of 20 patients (20%) had ≥10% RPVO at a median of 4 months follow-up. Following MT, the mean Miller score decreased from 24.5 ± 2.9 to 15.8 ± 3.3 (P < .001) and mean pulmonary artery pressure decreased from 36.1 ± 4.8 mm Hg to 26.8 ± 5.4 mm Hg (P < .001). Right ventricle–to–left ventricle ratio decreased from 1.44 ± 0.2 to 1.05 ± 0.24 by 24 to 48 hours (P < .001) and 0.85 ± 0.1 at 30 days (P < .001) and right ventricular systolic pressure decreased from 63.2 ± 10 mm Hg to 42.1 ± 9.8 mm Hg at 24 to 48 hours (P < .001) and 31.9 ± 10.4 at 30 days (P < .001). ConclusionsIn this prospective study of patients with submassive PE treated with MT, favorable rates of RPVO were noted in comparison to prior studies of anticoagulation alone along with expected acute hemodynamic and echocardiographic improvements. While this study was small in scope, the results suggest the potential for long-term benefits of MT in acute PE in addition to the acute benefits previously described.

Reduced fibrin clot permeability on admission and elevated E-selectin at 3 months as novel risk factors of residual pulmonary vascular obstruction in patients with acute pulmonary embolism

BackgroundResidual pulmonary vascular obstruction (RPVO) is common following pulmonary embolism (PE) but its association with fibrin clot properties is poorly understood. We investigated whether prothrombotic state and hypofibrinolysis markers can identify patients with RPVO.MethodsIn 79 normotensive noncancer patients (aged 56 ± 13.3 years) with acute PE, we determined fibrin clot permeability (Ks), clot lysis time (CLT), endogenous thrombin potential (ETP), fibrinolysis proteins, oxidative stress markers, and E-selectin on admission before initiation of anticoagulant therapy, after 5–7 days, and 3 months of anticoagulation. RPVO was diagnosed using computed tomography angiography 3–6 months since PE.ResultsPatients with RPVO (n = 23, 29.1%) had at baseline higher simplified Pulmonary Embolism Severity Index (sPESI) (P = 0.004), higher N-terminal brain natriuretic propeptide (P = 0.006) and higher D-dimer (P = 0.044). Patients with versus without RPVO had lower Ks (P < 0.001) and longer CLT (P < 0.05), both at baseline and 5–7 days since admission, but not at 3 months. Patients with RPVO showed 40.6% higher E-selectin (P < 0.001) solely at 3 months. By multivariable logistic regression, baseline Ks (odds ratio [OR] 0.010, 95% confidence interval [CI] 0.001–0.837, P = 0.042, per 10− 9 cm2), baseline D-dimer (OR 1.105, 95% CI 1.000-1.221, P = 0.049, per 100 ng/ml), and E-selectin levels after 3 months (OR 3.874, 95% CI 1.239–12.116, P = 0.020, per 1 ng/ml) were associated with RPVO.ConclusionsRPVO patients despite anticoagulation characterize with the formation of denser fibrin clots on admission and higher E-selectin at 3 months. Those parameters could be the potential novel RPVO risk factors that warrant further evaluation in an independent cohort.Graphical

PB0444 Residual Pulmonary Vascular Obstruction is Associated with Prothrombotic Fibrin Clot Phenotype in Patients Following Pulmonary Embolism

PB0444 Residual Pulmonary Vascular Obstruction is Associated with Prothrombotic Fibrin Clot Phenotype in Patients Following Pulmonary Embolism

Residual pulmonary vascular obstruction and recurrence after acute pulmonary embolism: a systematic review and meta-analysis of individual participant data

We aimed to assess the relationship between residual pulmonary vascular obstruction (RPVO) on planar lung scan after completion of at least 3 months of anticoagulant therapy for acute pulmonary embolism (PE) and the risk of recurrent venous thromboembolism (VTE) or death due to PE one year after treatment discontinuation. The systematic review was registered with the International Prospective Registry of Systematic Reviews (PROSPERO: CRD42017081080). The primary outcome measure was to generate a pooled estimate of the rate of recurrent VTE at one year in patient with RPVO diagnosed on planar lung scan after discontinuation of at least 3 months of anticoagulant treatment for an acute PE. Individual data were obtained for 809 patients. RPVO (ie, obstruction >0%) was found in 407 patients (50.3%) after a median of 6.6 months of anticoagulant therapy for a first acute PE. Recurrent VTE or death due to PE occurred in 114 patients (14.1%), for an annual risk of 6.4% (95% confidence interval, 4.7%-8.6%). Out of the 114 recurrent events, 63 occurred within one year after discontinuation of anticoagulant therapy corresponding to a risk of 8.1% (6.4%-9.8%) at 1 year. The risk of recurrent VTE at one year was 5.8% (4.4-7.2) in participants with RPVO <5%, vs 11.7% (9.5-13.8) in participants with RPVO ≥5%. RPVO is a significant predictor of the risk of recurrent venous thromboembolism. However, the risk of recurrent events remains too high in patients without residual perfusion defect for it to be used as a stand-alone test to decide on anticoagulation discontinuation.

PH Roundtable: Tailoring CTEPH Imaging for Evaluation and Postintervention Assessment—What Works and What’s New?

PH Roundtable: Tailoring CTEPH Imaging for Evaluation and Postintervention Assessment—What Works and What’s New?

Changes in Lung Perfusion in Patients Treated with Percutaneous Mechanical Thrombectomy for Intermediate-Risk Pulmonary Embolism

BackgroundCurrent pulmonary embolism treatment options rely heavily on anatomical clot location. However, anatomical location does not necessarily determine adverse outcomes; rather, clinical severity is secondary to the degree of perfusion impairment. Dual-energy computed tomography pulmonary angiogram (DE-CTPA) can map perfusion at the time of pulmonary embolism diagnosis. Single-photon emission computed tomography ventilation-perfusion scans allow for perfusion tracking similar to DE-CTPA. MethodsWe present 3 patients with intermediate-risk pulmonary embolism treated with mechanical thrombectomy using the Inari FlowTriever System (Inari Medical, Irvine, Calif). Lung perfusion scoring was applied to pre-procedure and post-procedure imaging. We graded perfusion of each lobe in 3 planes. If the entire lobe was perfused, a score of 3 was assigned. If lung perfusion is normal, total perfusion score is 15. All patients had pre-procedure and follow-up transthoracic echocardiograms. ResultsAll 3 patients were diagnosed with pulmonary embolism via DE-CTPA that showed right ventricle strain and had deep venous thrombosis. Following mechanical thrombectomy, patients immediately experienced improvement in perfusion score; scores continued to improve at follow-up. All patients also had improvement in right ventricle size or function on follow-up echocardiogram. DiscussionIntermediate-risk pulmonary embolism often has large initial clot burden that predicts residual pulmonary vascular obstruction. Residual pulmonary vascular obstruction is associated with increased risk of death, recurrent thrombus, and chronic thromboembolic pulmonary hypertension. Clot removal via thrombectomy may decrease the prevalence of residual pulmonary vascular obstruction by improving lung perfusion. We found that mechanical thrombectomy increased lung perfusion immediately and at follow-up assessments.

Predictors of residual pulmonary vascular obstruction after anticoagulation monotherapy in patients with intermediate-risk pulmonary embolism.

BackgroundPatients with intermediate-risk pulmonary embolism (PE) can be treated with anticoagulation monotherapy. However, clinicians are concerned as to whether anticoagulation monotherapy is sufficient to reduce mortality in patients with a large embolic burden, and to resolve vascular obstruction. We investigated whether anticoagulation monotherapy was appropriate in patients with intermediate risk PE in terms of the occurrence of residual pulmonary vascular obstruction (RPVO), and the factors that independently predict the occurrence of RPVO.MethodsThis was a multicenter retrospective observational study of patients at intermediate risk of PE who were admitted to three hospitals between January 2012 and December 2017.ResultsOf total 91 patients, the median age was 72 years and 37 (40.7%) were male. Twenty-five patients (27.5%) were diagnosed with RPVO during follow-up. Multivariate logistic regression revealed chronic lung disease [odds ratio (OR), 4.14; 95% confidence interval (CI), 1.243–13.797; P=0.021] and the ratio of the diameters of the main pulmonary artery and ascending aorta ratio (P/A ratio) >1.0 documented on a chest computed tomography (CT) at presentation (OR, 3.46; 95% CI, 1.113–10.770; P=0.032) were significant independent predictors of RPVO occurrence. The incidence of RPVO in patients without these two factors was only 9.7%, but in those with the two factors it was 60% (P=0.004).ConclusionsAnticoagulation monotherapy did not seem to be a sufficient treatment to reduce RPVO, but the outcome was similar to that of patients treated with other therapies. Therefore, considering the risk-benefit ratio, we do not need to change the initial treatment as systemic thrombolytic therapy or catheter-based therapy in patient with intermediate risk PE. Underlying chronic lung disease and a P/A ratio >1 on the initial chest CT predicted the occurrence of RPVO. Therefore, we should carefully assess persistent of dyspnea and exercise limitations using various methods in patients with these risk factors, to detect the occurrence of chronic thromboembolic pulmonary disease (CTEPD) earlier.

Association between initial and residual pulmonary vascular obstruction and pulmonary embolism recurrence, a pooled analysis

Introduction The best treatment option (short-term or extended anticoagulant treatment) after a first unprovoked pulmonary embolism (PE) is debated. Pulmonary vascular obstruction, measured by the pulmonary vascular obstruction index (PVOI) at diagnosis or during the follow-up, has been associated with an increased risk of venous thromboembolism (VTE) recurrence when anticoagulants are stopped [1] . But results are not entirely consistent [2] , and PVOI classification cut-offs vary among studies. We therefore conducted a pooled analysis of 3 studies of the F-CRIN INNOVTE network. The primary objective of this work is to assess if elevated PVOI at the time of PE diagnosis and after months of anticoagulation are independent risk factors of VTE recurrence after a first episode of PE, and if so, to estimate which PVOI cut-off values would be the most discriminating for predicting VTE recurrence. Method We performed a pooled analysis of individual data from 3 French studies conducted within the F-CRIN INNOVTE network: a randomised double-blind controlled clinical trial and two observational longitudinal cohort studies. PVOI was measured by ventilation/perfusion lung scan during two periods; one at the time of index PE (initial PVOI), and one several months later, after anticoagulation treatment of the acute phase (post-treatment PVOI). PVOI was expressed in percentage of vascular obstruction. VTE recurrence was defined as objectively confirmed PE episode or deep vein thrombosis. The associations between PVOI (both initial and post-treatment) and VTE recurrence were jointly estimated using a multivariate Cox proportional hazards regression model. To manage confounding, the model was further stratified on the study, as well as adjusted on anticoagulant treatment duration, which could have been affected by PVOI measurement in the two observational cohort studies. By this means, the direct effect of PVOI on VTE recurrence may be estimated. Optimal PVOI thresholds were estimated by 10-fold cross-validation, using areas under curve (AUC) computed from time-dependant receiver-operating characteristic (ROC) curves. Results The total number of patients was 922. The median duration of follow-up was 42 months (IQR: 38–60). Mean age was 60 ± 18 years, 56% of patients were female. VTE recurrences occurred in 149 patients (4.2 events per 100 person-years). The most discriminating cut-offs were > 35% for initial PVOI (AUC: 0.71, 95% CI: 0.71–0.71), and > 5% for post-treatment PVOI (AUC: 0.69, 95% CI: 0.68–0.69). Initial PVOI > 35% and post-treatment PVOI > 5% were significantly associated with the risk of VTE recurrences (HR 1.61, 95% CI: 1.07–2.43 and HR 1.63, 95% CI: 1.06–2.50, respectively). Conclusion After a first episode of PE, initial PVOI > 35% and post-treatment PVOI > 5% were found to be independent predictors of VTE recurrence. Those results could in the future help detect more accurately patients with high-risk of VTE recurrence, and thus provide help in clinical decision-making for adapting anticoagulation therapy.

Predictors of residual pulmonary vascular obstruction after pulmonary embolism: Results from a prospective cohort study

BackgroundWe aimed to determine the prevalence of residual pulmonary vascular obstruction (RPVO) after symptomatic pulmonary embolism (PE) and to identify risk factors for RPVO. MethodsOn the basis of a prospective cohort of patients with a documented symptomatic venous thromboembolism, we included patients who had an acute PE and underwent a ventilation/perfusion lung scan at 3 to 24 months during the follow-up after PE. RPVO score was assessed for each patient. Initial pulmonary vascular obstruction at PE diagnosis was also assessed when available. Univariable and multivariable analyses were performed with preselected data to identify predictors for persistent defect defined as RPVO ≥ 5%. ResultsAmong the 537 included patients, 278 (51.8%) had RPVO ≥ 5%, and 191 (35.6%) had RPVO ≥ 10%. In primary multivariate analysis on overall population, age ≥ 65 years (odds ratio [OR] 2.25, 95% CI, 1.45–3.52) and chronic respiratory failure (OR 3.19, 95% CI, 1.22–10.04) were independent predictors of RPVO ≥ 5%. In secondary multivariate analysis restricted to 256 patients with available initial pulmonary vascular obstruction score at index PE (IPVO), age ≥ 65 years (OR 2.78, 95% CI, 1.41–5.53), unprovoked PE (OR 2.11, 95% CI, 1.11–4.07) and IPVO ≥ 20% (OR 2.94, 95% CI, 1.68–5.20) were found to be independent risk factors for RVPO ≥5%. ConclusionIn this selected population of patients with an acute PE, age ≥ 65 years, unprovoked PE and IPVO ≥ 20% at PE diagnosis appeared to be risk factors for residual pulmonary vascular obstruction measured at three to 24 months.

Predictors for Residual Pulmonary Vascular Obstruction after Unprovoked Pulmonary Embolism: Implications for Clinical Practice-The PADIS-PE Trial.

We aimed to identify risk factors for residual pulmonary vascular obstruction after a first unprovoked pulmonary embolism (PE). Analyses were based on data from the double-blind randomized "PADIS-PE" trial that included 371 patients with a first unprovoked PE initially treated during 6 uninterrupted months; all patients underwent baseline ventilation-perfusion lung scanning at inclusion (i.e., after 6 months of anticoagulation). Each patient's pulmonary vascular obstruction indexes (PVOIs) at PE diagnosis and at inclusion were centrally assessed. Among the 371 included patients, residual PVOI was available in 356 patients, and 150 (42.1%) patients had PVOI ≥ 5%. At multivariable analysis, age > 65 years (odds ratio [OR], 2.81, 95% confidence interval [CI], 1.58-5.00), PVOI ≥ 25% at PE diagnosis (OR, 3.53, 95% CI, 1.94-6.41), elevated factor VIII (OR, 3.89, 95% CI, 1.41-10.8), and chronic respiratory disease (OR, 2.18, 95% CI, 1.11-4.26) were independent predictors for residual PVOI ≥ 5%. Patients with ≥ 1 of these factors represented 94.5% (123 patients) of all patients with residual PVOI ≥ 5%. Six months after a first unprovoked PE, age > 65 years, PVOI ≥ 25% at PE diagnosis, elevated factor VIII, or chronic respiratory disease were found to be independent predictors for residual pulmonary vascular obstruction. URL: http://www.controlled-trials.com. Unique identifier: NCT00740883.

Residual pulmonary vascular obstruction and recurrence after acute pulmonary embolism: protocol for a systematic review and meta-analysis of individual participant data

BackgroundIn patients with a first, unprovoked venous thromboembolism (VTE), the optimal duration of anticoagulant therapy (AT) is controversial due to tightly balanced risks and benefits of indefinite anticoagulation. The objective...

Fibrinogen and the prediction of residual obstruction manifested after pulmonary embolism treatment

Residual pulmonary vascular obstruction (RPVO) and chronic thromboembolic pulmonary hypertension (CTEPH) are both long-term complications of acute pulmonary embolism, but it is unknown whether RPVO can be predicted by variants of fibrinogen associated with CTEPH.We used the Akaike information criterion to select the best predictive models for RPVO in two prospectively followed cohorts of acute pulmonary embolism patients, using as candidate variables the extent of the initial obstruction, clinical characteristics and fibrinogen-related data. We measured the selected models' goodness of fit by analysis of deviance and compared models using the Chi-squared test.RPVO occurred in 29 (28.4%) out of 102 subjects in the first cohort and 46 (25.3%) out of 182 subjects in the second. The best-fit predictive model derived in the first cohort (p=0.0002) and validated in the second cohort (p=0.0005) implicated fibrinogen Bβ-chain monosialylation in the development of RPVO. When the derivation procedure excluded clinical characteristics, fibrinogen Bβ-chain monosialylation remained a predictor of RPVO in the best-fit predictive model (p=0.00003). Excluding fibrinogen characteristics worsened the predictive model (p=0.03).Fibrinogen Bβ-chain monosialylation, a common structural attribute of fibrin, helped predict RPVO after acute pulmonary embolism. Fibrin structure may contribute to the risk of developing RPVO.

Detection of Residual Pulmonary Vascular Obstruction by Ventilation-Perfusion Lung Scan Late After a First Pulmonary Embolism

The long-term impact of persistent pulmonary vascular obstruction after pulmonary embolism (PE) remains unknown. Based on ventilation-perfusion lung scan performed at discharge and 3months after a first PE, we aimed to investigate the prognostic value on 5-year adverse events of (1) residual pulmonary vascular obstruction (RPVO) at discharge (DIS-RPVO), (2) RPVO at 3months (3M-RPVO), and (3) relative change in RPVO between the 2 scans (RC-RPVO). We performed a prospective, multicenter cohort study from January 2007 to December 2009 including patients who survived at least 3months after a PE. RC-RPVO was defined as (DIS-RPVO- 3M-RPVO)/DIS-RPVO. The primary end point was a combined end point at 5years, composed of all-cause death, recurrent venous thromboembolism, chronic thromboembolic pulmonary hypertension, heart failure, and rehospitalization for cardiac causes. Receiver-operating characteristic curves were computed to define thresholds of DIS-RPVO, 3M-RPVO, and RC-RPVO predictive of the primary combined end point at 5years. Overall, 241 patients were included (high-risk PE: 11.2%, intermediate-risk PE: 51.8%, low-risk PE: 37%). Mean DIS-RPVO was 27.9 ± 15.1%, mean 3M-RPVO was 10.3 ± 10.8%, and mean RC-RPVO was 61.7 ± 33.4%. At 5years, 112 patients (46.5%) experienced the combined end point. Both 3M-RPVO ≥15% and RC-RPVO ≤37.5% were independently related to the occurrence of the combined end point at 5years (p= 0.01 and p= 0.02, respectively). DIS-RPVO did not predict long-term adverse events. In conclusion, RC-RPVO ≤37.5% and 3M-RPVO ≥15% were independently related to the occurrence of adverse events 5years after a first PE.

Residual pulmonary vascular obstruction and recurrence after acute pulmonary embolism. A single center cohort study

IntroductionUp to 50% of patients with pulmonary embolism (PE) present lung perfusion defects after six months of anticoagulant treatment, suggesting residual pulmonary vascular obstruction (RPVO). The risk of recurrence in patients with RPVO remains unknown. The present study aims to assess the risk of recurrent venous thromboembolism (VTE) in patients with RPVO after a first symptomatic episode of PE. MethodsConsecutive patients who survived a first objectively proven acute PE, treated for at least three months with anticoagulants, were included and followed prospectively. RPVO was defined as a pulmonary vascular obstruction of >10% on ventilation/perfusion lung scan performed at inclusion. Objectively proven VTE recurrences were registered and confirmed by an investigator unaware of the result of the ventilation/perfusion lung scan. ResultsAmong the 310 patients (median age: 61years) included in the study, 60 (19%) had RPVO. During a median follow-up of 51.3months, 66 patients (21.2%, 95% CI [17.5–26.7]) experienced recurrent VTE. In an adjusted cox proportional hazards analysis, we identified RPVO (HR 1.94; 95% CI [1.11–3.39]; p=0.026) and unprovoked PE (HR 3.56; 95% CI [1.79–7.07]; p=0.00051) as independent risk factors for recurrent VTE whereas extended anticoagulation therapy (HR 0.19; 95% CI [0.07–0.55]; p=0.00014) was associated with a low risk of recurrence. ConclusionThe results suggest that RPVO is an independent risk factor of recurrent VTE after a first PE.

LONG-TERM CLINICAL IMPLICATIONS OF RESIDUAL PULMONARY VASCULAR OBSTRUCTION AFTER PULMONARY EMBOLISM: A VENTILATION-PERFUSION LUNG SCAN FOLLOW-UP STUDY AT TWO TIMEPOINTS

Little is known about the clinical implications of residual pulmonary vascular obstruction(RPVO) on long-term outcomes and about the optimal timing of V-Q scan control during patient follow-up. We aimed to investigate the prognostic value on 5-year adverse events of RPVO, measured by two ventilation

0300: Course of vascular obstruction after pulmonary embolism as assessed by ventilation-perfusion lung scan follow-up

We investigated the course of residual pulmonary vascular obstruction (RPVO) from discharge up to 3 – 6 months after pulmonary embolism (PE). Prospective registry including 202 consecutive patients with PE who survived the acute phase (high risk PE: 12.4%, intermediate-risk: 65.8%, and low- risk: 21.8%). Patients with a prior history of chronic pulmonary disease were excluded. Ventilation-perfusion (V/Q) lung scan was performed in all patients before discharge, and again at follow-up (between 3 and 6 months after discharge). Treatment was in accordance with current guidelines. Evolution of RPVO was determined as the relative change in lung perfusion (in %) between discharge and follow-up V/Q scans. Between both lung scans, RPVO decreased from 29.1±15% to 10.9±11.4%, with an average relative change of 61.7±33.4%. Overall, 49 patients (24.2%) presented a full resolution of lung perfusion. Relative change in RPVO was <50% in57 (28%), including 18 (8.9%) patients who showed no modification on lung scan. The relative change in RPVO was constant, regardless of the level of RPVO at discharge (p=0.07). Patients who presented full resolution on the second lung scan (n=49) had significantly lower RPVO at discharge as compared to those without full resolution (21.7±10.1% vs. 31.4±16.0% respectively, p<0.001), and almost 75% of those with full resolution had RPVO<30% at discharge. Multivariate logistic regression showed that high-risk PE and right ventricle (RV) to left ventricle (LV) ratio (by quartiles) at discharge were independently related to unfavorable course of RPVO during follow-up (high-risk PE: OR 3.6, 95% CI 1.54-8.43, p<0.001; RV/LV ratio: OR 3.42, 95% CI 1.12-9.45, p=0.03). Our findings suggest that systematic lung scan follow-up should not be considered after PE, except in patients with high-risk PE or those with echocardiographic signs of RV pressure overload at discharge.

214: Interpreting troponin elevation in relation to symptom onset in intermediate-risk pulmonary embolism

Troponin elevation in the setting of acute pulmonary embolism (PE) is of small magnitude and short duration and can go unnoticed in pts referred late after symptom onset. Prospective, single-center registry of pts with confirmed intermediate-risk PE, defined as at least 1 echocardiographic finding of right ventricular (RV) dysfunction (endo-diastolic (EDRV)/left ventricular (EDLV) end-diastolic diameter ratio >=1 in the 4-chamber view, paradoxical septal systolic motion or pulmonary hypertension defined as RV/atrial gradient >30mmHg), or positive troponin test. Combined in-hospital endpoint was defined as death, non-fatal recurrent PE, or residual pulmonary vascular obstruction (RPVO) ≥35%. 282 pts were included, age 66±14 years, 59% women, 174 (62%) referred ≤5 days after symptom onset, 108 (38%) after >5 days. Troponin elevation was observed in 126 (72%) treated within ≤5 days, in 60 (56%) treated after >5 days (p=0.004). A significant interaction was observed between time since symptom onset and both troponin elevation and persistence of EDRV/EDLV diameter ratio>1 at 48h. The negative predictive value of troponin elevation was 85% in patients treated within 5 days of symptoms, but fell to 70% in those admitted >5 days after symptom onset (p=0.002). Positive troponin was an independent predictor of adverse outcome (OR=1.43 [1.08-5.56]). ROC curves show that prognostic value of positive troponin test was higher in pts referred ≤5 days than in pts referred >5 days after symptom onset (p=0.01). There is a significant relation between troponin elevation and time since symptom onset in patients with intermediate-risk PE. Negative predictive value of troponin elevation is adequate in pts treated early (≤5 days) but is suboptimal in pts treated >5 days after symptom onset. Table Results <=5 days since symptom onset >5 days since symptom onset p Sensitivity 72% (61.3-82.7) 51% (42.4-59.6) 0.005 Specificity 42% (44.5-49.5) 47% (39.1-54.9) 0.33 PPV 26% (18.4-33.6) 30% (22.2-37.8) 0.81 NPV 85% (78.4-91.6) 70% (63-77) 0.002

Long-term prognostic value of residual pulmonary vascular obstruction at discharge in patients with intermediate- to high-risk pulmonary embolism

We evaluated prognostic value at 6 months of residual pulmonary vascular obstruction (RPVO) measured before discharge in patients with intermediate- or high-risk pulmonary embolism (PE). Prospective registry including 416 consecutive patients with intermediate- or high-risk PE who survived the acute phase. Patients with previous cardiopulmonary disease were excluded. Perfusion lung scans were performed within 6-8 days after the onset of treatment. Residual pulmonary vascular obstruction was graded as the proportion of the lung not perfused. Primary objective was a combined endpoint at 6 months, including death, recurrent PE, and appearance of signs of heart failure. At 6 months, 32 patients (7.7%) had at least one adverse event: 12 deaths (2.9%), 12 recurrent PE (2.9%), and 14 (3.4%) heart failure. Independent predictors of combined endpoint were: cancer [odds ratio (OR) 3.07 (1.22-7.85)]; renal insufficiency at admission [OR: 2.53 (1.17-5.8)]; persistent signs of right ventricular dysfunction at 48 h echography [OR: 3.99 (1.36-11.3)]. The severity of RPVO at discharge was significantly associated with an unfavourable outcome [OR: 2.66 (1.58-3.93)]. The incremental prognostic value of RPVO information was confirmed by significantly improved goodness-of-fit. Threshold RPVO for predicting adverse events was estimated at 35% [area under the curve = 0.76 (0.73-0.82)]. Patients with RPVO greater than threshold at discharge had a significantly higher risk of death at 6 months (P = 0.01). Residual pulmonary vascular obstruction evaluated before hospital discharge in patients with intermediate- to high-risk PE is a powerful prognostic factor for a 6-month outcome. RPVO ≥35% is associated with an increased risk of adverse events at 6 months.

Long-term outcome of patients with persistent vascular obstruction on computed tomography pulmonary angiography 6 months after acute pulmonary embolism

The incidence and clinical significance of pulmonary residual thrombosis 6 months after an acute pulmonary embolism (PE) are still not well-known. To evaluate the association between residual vascular obstruction and the risk of venous thromboembolism (VTE) recurrence or death. Computed tomography pulmonary angiography (CTPA) was repeated in 97 consecutive patients 6 months after an acute episode of hemodynamically stable pulmonary embolism. We assessed the long-term consequences of residual thrombosis on vital status and incidence of recurrent VTE. Six patients were lost for follow-up. The remaining 91 patients were classified according to the presence (Group 1: 18 cases) or absence (Group 2: 73 cases) of residual pulmonary vascular obstruction. After a mean ± SD of 2.91 ± 0.99 years, there were eight (8.8%) deaths and 11 (12.1%) VTE recurrences. Groups 1 and 2 did not differ in the incidence of death or VTE recurrence. Persistent pulmonary vascular obstruction on 6-month CTPA did not predict long-term adverse outcome events.