|Year : 2016 | Volume
| Issue : 3 | Page : 134-142
Central versus peripheral pulmonary embolism: Analysis of the impact on the physiological parameters and long-term survival
José Luis Alonso Martinez, Francisco Javier Anniccherico Sánchez, Miren Aranzazu Urbieta Echezarreta, Ione Villar García, Jorge Rojo Álvaro
Department of Internal Medicine, Section A, Hospital Complex of Navarra, Pamplona, Spain
|Date of Web Publication||21-Mar-2016|
José Luis Alonso Martinez
Department of Internal Medicine, Section A, Hospital Complex of Navarra, Irunlarrea 6, Pamplona -31008, Navarra
Source of Support: None, Conflict of Interest: None
Background: Studies aimed at assessing whether the emboli lodged in the central pulmonary arteries carry a worse prognosis than more peripheral emboli have yielded controversial results. Aims: To explore the impact on survival and long-term prognosis of central pulmonary embolism. Patients and Methods: Consecutive patients diagnosed with acute symptomatic pulmonary embolism by means of computed tomography (CT) angiography were evaluated at episode index and traced through the computed system of clinical recording and following-up. Central pulmonary embolism was diagnosed when thrombi were seen in the trunk or in the main pulmonary arteries and peripheral pulmonary embolism when segmental or subsegmental arteries were affected. Results: A total of 530 consecutive patients diagnosed with pulmonary embolism were evaluated; 255 patients had central pulmonary embolism and 275 patients had segmental or subsegmental pulmonary embolism. Patients with central pulmonary embolism were older, had higher plasma levels of N-terminal of the prohormone brain natriuretic peptide (NT-ProBNP), troponin I, D-dimer, alveolar-arterial gradient, and shock index (P < .001 for each one). Patients with central pulmonary embolism had an all-cause mortality of 40% while patients with segmental or subsegmental pulmonary embolism (PE) had an overall mortality of 27% and odds ratio of 1.81 [confidence interval (CI) 95% 1.16-1.9]. Survival was lower in patients with central PE than in patients with segmental or subsegmental pulmonary embolism, even after avoiding confounders (P = .018). Conclusions: Apart from a greater impact on hemodynamics, gas exchange, and right ventricular dysfunction, central pulmonary embolism associates a shorter survival and an increased long-term mortality.
Keywords: Cardiac peptides, central pulmonary embolism, pulmonary embolism, survival
|How to cite this article:|
Alonso Martinez JL, Anniccherico Sánchez FJ, Urbieta Echezarreta MA, García IV, Álvaro JR. Central versus peripheral pulmonary embolism: Analysis of the impact on the physiological parameters and long-term survival. North Am J Med Sci 2016;8:134-42
|How to cite this URL:|
Alonso Martinez JL, Anniccherico Sánchez FJ, Urbieta Echezarreta MA, García IV, Álvaro JR. Central versus peripheral pulmonary embolism: Analysis of the impact on the physiological parameters and long-term survival. North Am J Med Sci [serial online] 2016 [cited 2020 Oct 27];8:134-42. Available from: https://www.najms.org/text.asp?2016/8/3/134/179128
| Introduction|| |
With the increasing use of the computed tomography (CT) angiography as the main diagnostic method in pulmonary thromboembolism, new approaches for categorizing the severity of pulmonary embolism have been conducted mainly based on thrombus burden and its impact on the right ventricle. ,,,,,,,,,,,,,,,, Data from radiographic studies, which used CT angiography to evaluate the prognostic factors associated with pulmonary embolism (such as the relationship between the diameter of the right ventricle and the diameter of the left ventricle, the bowing of the interventricular septum, ,,, the thrombus burden, ,,, the reflux contrast to the cava,  and the diameter of the pulmonary artery regarding the azygos vein) have been studied as prognostic factors of morbidity and mortality in the context of acute pulmonary thromboembolism.
The impact of pulmonary embolism on the right ventricle measured by biomarkers and D-dimer has also been correlated with the thrombotic burden in several investigations, , and recently the European Society of Cardiology has included the right ventricular dysfunction in the risk assessment of pulmonary embolism  evaluated by echocardiography as well as measured by CT though in both cases the prediction of an adverse outcome has been difficult to standardize.
The location of the thrombi in the pulmonary arterial tree has received some attention as a prognostic factor. Prognosis is worse when the trunk or main pulmonary arteries are occupied by thrombi with either complete or incomplete occlusion ,,, although this has not been shown consistently in all studies since several of them have been unable to demonstrate an association between image scores and mortality. ,,
Although many radiologists consider a pulmonary embolism to be massive when thrombi are visualized in the main pulmonary arteries, the current criterion is the state of the blood pressure, categorizing the patients as normotensive or hypotensive patients, with the latter needing fibrinolysis. However, a number of normotensive patients develop clinical deterioration requiring subsequent thrombolysis. Therefore, this has contributed to the conclusion that size does not matter. 
A recent meta-analysis assessing the localization of emboli visualized at CT angiography was useful for the stratification of patients  though there was no correlation between the obstruction index and prognosis. Another meta-analysis has concluded that the strongest radiological predictive value for adverse outcome in patients with pulmonary embolism is the right to left ventricular ratio measured on CT. 
However, the analysis of the adverse outcomes using as predictive tools the CT angiography and echocardiography both have been estimated at short-term [i.e., in-hospital and 30-days mortality or intensive care unit (ICU) admission].
To our knowledge, there are no studies approaching the long-term prognosis of pulmonary embolism affecting the main pulmonary arteries. Therefore, our aim was to study the prognostic significance of pulmonary embolism affecting pulmonary arteries of different sizes and to check the survival in the long term differentiating central pulmonary embolism and peripheral pulmonary embolism.
| Patients and Methods|| |
In the period 2004-2013, all consecutive outpatients hospitalized in the Internal Medicine Service Department with a diagnosis of acute symptomatic hemodynamically stable pulmonary embolism, diagnosed by helical chest CT, and were evaluated within 24 h of admission. This study was approved by the local ethics committee. Because the study was observational and did not interfere with diagnostic or therapeutic work-ups, informed consents were not obtained. Each patient approved and signed the informed consent for radiologic contrast administration.
Study design and methods
Systematically, we recorded on admission the blood pressure, shock index (the ratio of heart rate to systolic blood pressure), heart and respiratory rates, blood gases value before supplementary oxygen administration, electrocardiographic recording, days of symptoms up to diagnosis, and calculated alveolar-arterial difference of oxygen. Alveolar-arterial oxygen gradient was calculated as:
FiO2 (Pb-47) _ PACO2/R _ F1O2/R (1-R) (PaCO2/R) _ PaO2
where FIO2 is the O 2 inspiratory fraction, Pb is the barometric pressure, and PACO 2 is alveolar CO 2 pressure, PaCO 2 is arterial CO 2 pressure, assumed to be equal to PCO 2 , and PaO 2 is arterial oxygen pressure. R is the respiratory exchange ratio, set to be 0.8.
Single-slice helical CT was used for diagnosis in 23% of the patients and multidetector scanner of 64 rows was used for diagnosis in the rest; both were general electric devices (Medical Systems, Milwaukee, WI, USA). One mm slices and standard sequential acquisition were obtained in every patient. Breath-hold acquisition was employed. After the intravenous injection of contrast material, the scanning area comprised the chest and upper abdomen, acquiring images in the craniocaudal direction. Central PE was diagnosed when thrombi were visualized in the main trunk of the pulmonary artery and/or in the right or left main pulmonary arteries. Peripheral PE was diagnosed when thrombi were seen exclusively in segmental or subsegmental pulmonary arteries. Each scan was read by a radiologist as in usual clinical practice. Radiologists were blinded to the clinical, laboratory outcomes and survival. Subsequently, the scans were also reviewed by investigators belonging to the Internal Medicine Service Department.
Thrombotic burden was calculated with the formula for the CT obstruction index  applied to the initial CT angiography, which was diagnostic of pulmonary embolism. Each lung is considered to have 10 arteries, 3 in the upper lobe, 2 in the middle lobe and lingula, and 5 in the lower lobe. The presence of embolus in a segmental artery was scored as 1 point, and emboli in the most proximal arterial level was scored as the value equal to the number of segmental arteries arising distally. A weight factor was assigned depending on the degree of vascular obstruction: 1 point when the thrombus was partially occlusive, and 2 points with total occlusion. Therefore, maximal CT obstruction index was 40 points. The percentage of vascular pulmonary obstruction was calculated as follows: n·d/40 × 100 where n is the value of the proximal thrombus in the pulmonary arterial tree equal to the number of segmental branches arising distally and d is the degree of obstruction.
The degree of pulmonary obstruction was calculated by the clinicians who were taking care of the patients and they were authors belonging to the Internal Medicine Department. We scored 2 points for the artery where the irrigated territory of a pulmonary infarction was seen and when contrast was not observed distal to the thrombus. The rest of the cases were scored 1 point.
In every patient, blood was drawn within 24 h of admission for pro-BNP and troponin I determination. Plasma D-dimer levels were measured previously in the emergency ward. Echocardiography was not routinely performed.
The coexistence of deep venous thrombosis was diagnosed when lower limb swelling was present and confirmed with venous Doppler ultrasound.
Standard therapy consisted of enoxaparin 1 mg/kg twice a day for 3-5 days, initiation of oral anticoagulants (coumarone) on the first day of hospitalization, overlap of enoxaparin and oral anticoagulants for a minimum of 3 days, and cessation of enoxaparin when international normalized ratio (INR) was greater than 2. During hospitalization fibrinolysis was subsequently indicated in three patients due to hemodynamic instability. After treatment with enoxaparin, secondary prophylaxis was made with direct action anticoagulants in seven patients: Apixaban-two patients, rivaroxaban-4 patients, and dabigatran-1 patient.
Death rate was defined as deaths by all causes during hospitalization and those occurring at follow-up. The cause of death by recurrent pulmonary embolism was considered when new thrombotic material in the pulmonary arterial tree was demonstrated either with angiography CT or lung scan and also when the patient had a sudden death with dyspnea.
Cardiovascular death included patients who died because of myocardial infarction, heart failure, or reported ventricular dysrrhytmias. Death by all causes was considered in the mortality rate. When the death occurred in the hospital, the cause was adjudicated by one of the researches involved in the study or taken from clinical reports by primary care physicians and death certificates.
All continuous variables were tested for normal distribution with the Kolmogorov-Smirnov test. Continuous variables are expressed as median and interquartile range (IQR) for variables without normal distribution and as mean ± standard deviation (SD) for variable with Gaussian distribution.
Comparison of the two means was performed with the t-test for normally distributed variables and with the Mann-Whitney U test for non-Gaussian variables. Fisher's exact test and χ2 test were used for proportional comparisons.
Survival analysis was made by using the Mantel-Haenszel test. We tested survival at several times after the index episode in order to see the short-, mid-, and long-term survivals.
The independence of significant variables obtained from bivariant statistical analysis for central pulmonary embolism was tested with logistic regression by means of a step-by-step process, eliminating those variables without a level of significance <.05 up to reach of the last useful model. We used standardized coefficient due to the wide variability in measurement units.
All statistical tests were two-tailed, and a P < 0.05 was considered to be statistically significant. P values greater than 0.05 were considered to be nonsignificant.
| Results|| |
In the period from January 2004 to December 2013, 530 consecutively hospitalized patients because of acute pulmonary embolism were analyzed. Patients were traced during a total time period of 12 years.
The median time of follow-up was 34 (IQR 52) months. The median age was 76 (IQR 16) years, and 45% were male. Demographic and baseline data are depicted in [Table 1].
|Table 1: Demographic, baseline characteristics, and differential characteristics between central and peripheral pulmonary embolism|
Click here to view
Central pulmonary embolism was diagnosed in 255 (48.5%) patients and segmental or subsegmental (peripheral) thromboembolism in 275 (51.5%) patients. The median age of central pulmonary embolism was 78 (IQR: 13) years while the median age of peripheral pulmonary embolism was 74 (IQR: 18) years (P < .001). The concordance between the readings of CT angiography by the radiologist and internist doctors was kappa 0.87.
Fifty-nine (23%) patients with central pulmonary embolism and 56 (20%) patients with peripheral pulmonary embolism had previous cardiac disease (P = .43). Twenty-five (10%) patients had central pulmonary embolism and 39 (14%) patients had chronic respiratory disease (P = .11).
Patients with central pulmonary embolism showed a smaller proportion of clinical deep venous thrombosis (28% versus 37% P < .05 CI 95% 0.019-0.17), higher burden of pulmonary thrombi and higher plasma levels of N-terminal of the prohormone brain natriuretic peptide (NT-ProBNP), troponin I, D-dimer, alveolar to arterial gradient of oxygen, shock index, and respiratory rate (P < .001 in each one of the above) while they showed lower arterial partial pressure of oxygen (P < .001), lower arterial partial pressure of carbon dioxide (P < .001), and systolic blood pressure (P < .05) than patients with peripheral pulmonary embolism [Table 1].
Bleeding occurred in 21 (4%) patients, brain hemorrhage in 10 patients (central pulmonary embolism in 6 and peripheral pulmonary embolism in 4 patients, P = .53), gastrointestinal hemorrhage in 6 patients (central pulmonary embolism in 1 patient and peripheral pulmonary embolism in 5 patients, P = .21), and one retroperitoneal hemorrhage, one muscle hemorrhage, and one hematuria requiring blood transfusion in central pulmonary embolism, and two hematurias in peripheral pulmonary embolism.
Continuous anticoagulant therapy was indicated in 217 (41%) patients with central pulmonary embolism and in 110 (43%) patients with peripheral pulmonary embolism (P = .32).
During follow-up, 102 (40%) patients with central pulmonary embolism at the index episode died while 74 (27%) patients who had a segmental or subsegmental pulmonary embolism died (P < .01 CI 95% 0.04-0.21); odds ratio was 1.81 (CI 95% 1.16-1.9).
The median time up to death of patients who had central pulmonary embolism was 19.5 (IQR 52) months after the episode of pulmonary embolism. The median time up to death in patients with segmental or subsegmental pulmonary embolism was 11.62 (IQR 31.9) months (P = .14). We show in [Table 2] mortality at different times from the initial episode.
|Table 2: Mortality at different times in patients with central or peripheral pulmonary embolism|
Click here to view
The analysis of survival curves showed a longer survival in patients with segmental and subsegmental pulmonary thrombi than in patients with central pulmonary thrombi at 10 months (P = .03), 26 months (P = .03), and 96 months (P = .0005). When we adjusted the survival curves for patients without previous cardiac and respiratory diseases and cancer, we observed that the survival continued to be better in segmental or subsegmental pulmonary embolism than in central pulmonary embolism (P = .018) [Figure 1].
|Figure 1: The curves of survival shown have been adjusted for confounders: Patients with cardiac, respiratory disease, or cancer have not been included in the analysis|
Click here to view
The thrombi burden of dead patients was 33.75% (IQR: 25) while the thrombi burden of survivors was 30% (IQR: 32.25) (P < .001).
Fifty-four patients died while they were on anticoagulant therapy, 34 (33%) belonging to the group of central pulmonary embolism and 21 (28%) belonging to the group of peripheral pulmonary embolism (P = .48). In 40 (39%) patients with central pulmonary embolism who died, anticoagulation had been withdrawn 7 ± 5 months after the initial episode and in 31 (42%) patients with peripheral pulmonary embolism (P = .72 and P = .21 respectively). [Table 3] shows the causes of death, globally and separated by groups of central or peripheral pulmonary embolism.
|Table 3: Causes of death classifi ed by central or segmental and subsegmental (peripheral) pulmonary embolisms|
Click here to view
At the follow-up, patients dead because of a recurrent pulmonary embolism were 18 (7%) belonging to the group of central pulmonary embolism and 9 (3%) belonging to the group of peripheral pulmonary embolism (P < .05 CI 95% 0.003-0.07).
When the initial episode was a central pulmonary embolism, the patients died because of a recurrent pulmonary embolism at a median time of 0.28 (IQR: 13) months while patients who had had peripheral pulmonary embolism died because of a recurrent pulmonary embolism 18 (IQR: 46) months later (P = .12).
Deaths caused by recurrent pulmonary embolism occurred in 12 (40%) patients with permanent anticoagulation, which had a median value of prothrombin in therapeutic range of between 2 and 3 of 61.5%, and in 15 (60%) patients in whom anticoagulation was withdrawn.
Twenty-nine patients (11%) with central pulmonary embolism and 10 (4%) patients with peripheral pulmonary embolism both at the index episode died because of different cancers (P < .001 CI 95% 0.02-0.12). Deaths by cancer in patients with central pulmonary embolism occurred 19 (IQR: 40) months after the initial episode and 6.6 (IQR: 33) months after the initial episode in those patients with peripheral pulmonary embolism (P nonsignificant).
In [Table 4], we show the results of logistic regression analysis. Independent variables predicting death were the age of the patient at the index episode (OR 2.89 CI 95% 1.04-1.10), the development of cancer during the follow-up of the patient (OR 1.48 CI 95% 1.64-7.71), the central thrombi at the index episode (OR 1.31 CI 95% 1.007-3), and the plasma level of NT-ProBNP measured at the index episode (OR 1.61 CI 95% 1.0001-1.0002). Respiratory rate at the index episode was not an independent predictive variable of death.
| Discussion|| |
Although the localization of pulmonary emboli within the pulmonary arterial tree is not currently considered a matter of severity, there are several studies supporting the fact that the closer to the right ventricle the pulmonary emboli are, the earlier and higher the sort-term mortality is  while emboli affecting small pulmonary arteries carry a better prognosis. However, not all studies have shown a direct relationship between the size of the occluded vessel and mortality, with several investigations including a moderate number of patients ,, unable to show a correlation between image and prognosis.
In the same way, the arterial obstruction index has shown to be useful in several investigations in order to predict right ventricular dysfunction and death although in a recent meta-analysis, despite the localization of pulmonary emboli assessed by CT angiography show usefulness for risk stratification, the obstruction index did not show a relation with prognosis. 
In our patients, the central localization of emboli with respect to segmental or subsegmental emboli was associated with more stress of the right ventricle measured with higher plasma levels of NT-ProBNP and troponin I and a more intense disorder in gas exchange and hemodynamic status.
The clot burden was also higher in central pulmonary embolism than in segmental and subsegmental pulmonary embolisms. However, this fact seems derived from the characteristic of the equation for calculating the clot burden since it could not demonstrate whether it is an independent factor in the prediction of death.
Patients with segmental and subsegmental pulmonary embolisms had more clinically overt signs of deep venous thrombosis than patients with central pulmonary embolism. This fact could be explained by migration of thrombi from the lower limbs to the pulmonary circulation in patients with central pulmonary embolism showing a higher thrombi burden. A defective fibrinolytic system joined to a higher degree of hypoxemia and activation of inflammatory pathways could also interact, favoring the greater size of emboli although in our patients a higher plasma level of D-dimer goes against quantitative defects in fibrinolysis.
On the other hand, our patients were mostly the elderly and the age of patients with central pulmonary embolism was higher than the age of patients with segmental and subsegmental pulmonary embolisms. In this way, defective fibrinolysis and endothelial function have been showed in the elderly, and so all these factors could contribute to the higher size of emboli,  which would cause the lodging of thrombi in the proximal pulmonary arteries.
In our study, patients with central lodged thrombi showed a higher overall mortality than patients with more peripheral pulmonary embolism, with more mortality rate specifically due to subsequent pulmonary embolism, cancer, and bleeding. However, neither the time of anticoagulant therapy of patients with central and more peripheral pulmonary embolism nor the proportion of patients dead while they were under anticoagulant therapy were different enough to explain the higher mortality of central pulmonary embolism. The number of patients with direct-action anticoagulants was too small to analyze and to draw valid conclusions.
Survival in patients with central pulmonary embolism was significantly lower than in patients with segmental or subsegmental thrombi. Subanalysis at different times from the initial episode also demonstrated an increased mortality for central pulmonary embolism at short- (i.e. ,10 months), mid- (i.e., 26 months), and long terms (i.e., 96 months).
In our patients, the in-hospital mortality rate measured at 15 days and 30 days was lower than the mortality reported in the literature, which has been estimated to range 9-11% at 30 days and 8.6-17% at 3 months. ,,, The high long-term mortality in our study (33%) may be explained in part by the advanced age of our patients.
Variables such as gas exchange data, hemodynamic values, the plasma level of troponin I, clot burden, and absence of overt signs of deep venous thrombosis disappeared from the model of logistic regression on losing significance.
In the final model, independent variables predicting death were the age of the patient and plasma level of NT-ProBNP, both measured at the index episode, and the development of cancer during the follow-up of the patients while the segmental or subsegmental pulmonary embolism was a protective factor. In the final model, the respiratory rate remained although it did not show any significance.
However, our study had several limitations. The patients were taken from a single center; therefore, our results should be tested in other studies or in meta-analysis. Although radiologists who interpreted the CT angiography were blinded for the study, different assessments of the localization of thrombi made by them could have been due to the fact that the radiologists on duty were not always specialized in thorax radiology. Thereafter, the review of the scans for the authors belonging to Internal Medicine Department produced a high level of concordance, playing down the potential bias. Another limitation of our study was that the death of a number of patients occurred because of unknown causes although the number was similar in both groups, minimizing the impact over the other causes of death.
Another potential limitation of our study could be due to an overestimation of deaths caused by recurrent pulmonary embolism since sudden deaths were included as recurrent pulmonary embolism and they might have occurred by other causes such as ventricular arrhythmia.
Patients of this study were mostly hemodynamically stable with a few patients needing subsequent fibrinolysis. Thereafter, our results cannot be extrapolated to patients with hemodynamic instability but only to patients who meet the criteria for submassive or nonmassive pulmonary embolism.
A potential strength of our study is the fact that it was conducted in a relatively closed community. This fact has allowed a close follow-up of the patients with no patient being lost.
| Conclusions|| |
Patients with hemodynamically stable acute pulmonary embolism, which show thrombi lodged in the main pulmonary arteries have a higher overall mortality and lower survival than patients with segmental or subsegmental pulmonary embolism.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Araoz PA, Gotway MB, Trowbridge RL, Bailey RA, Auerbach AD, Reddy GP, et al
. Helical CT pulmonary angiography predictors of in-hospital morbidity and mortality in patients with acute pulmonary embolism. J Thorac Imaging 2003;18:207-16.
van der Meer RW, Pattynama PM, van Strijen MJ, van den Berg-Huijsmans AA, Hartmann IJ, Putter H, et al
. Right ventricular dysfunction and pulmonary obstruction index at helical CT: Prediction of clinical outcome during 3-month follow-up in patients with acute pulmonary embolism. Radiology 2005;235:798-803.
Moroni AL, Bosson JL, Hohn N, Carpentier F, Pernord G, Ferretti GR. Non-severe pulmonary embolism: Prognostic CT findings. Eur J Radiol 2011;79:452-8.
Bazeed MF, Saad A, Sultan A, Ghanem MA, Khalil DM. Prediction of pulmonary embolism outcome and severity by computed tomography. Acta Radiol 2010;51:271-6.
Araoz PA, Gotway MB, Harrington JR, Harmsen WS, Mandrekar JN. Pulmonary embolism: Prognostic CT findings. Radiology 2007;242:889-97.
Díaz JC, Ladrón de Guevara D, Pereira G, Herrmann R, Silva C, Astorga E, et al
. Predictive values for mortality in pulmonary embolism, of embolic load and right/left ventricular diameter ratio, measured by computed tomography. Rev Med Chil 2007;135:1437-45.
Nural MS, Elmali M, Findik S, Yapici O, Unzun O, Sunter AT, et al
. Computed tomographic pulmonary angiography in the assessment of severity acute pulmonary embolism and right ventricular dysfunction. Acta Radiol 2009;50:629-37.
Engelke C, Rummeny E, Marten K. Acute pulmonary embolism: Prediction of cor pulmonale and short-term patient survival from assessment of cardiac dimensions in routine multidetector-row CT. Rofo 2006;178:999-1006.
Ghaye B, Ghuysen A, Willems V, Lambermont B, Gerard P, D'Orio V, et al
. Severe pulmonary embolism: Pulmonary artery clot load scores and cardiovascular parameters as predictors of mortality. Radiology 2006;239:884-91.
Becattini C, Agnelli G, Vedovati MC, Pruszczyk P, Casazza F, Grifoni S, et al
. Multidetector computed tomography for acute pulmonary embolism: Diagnosis and risk stratification in a single test. Eur Heart J 2011;32:1657-63.
Kang DK, Thilo C, Schoepf UJ, Barraza JM Jr, Nance JW Jr, Bastarrika G, et al
. CT signs of right ventricular dysfunction: Prognostic role in acute pulmonary embolism. JACC Cardiovasc Imaging 2011;4:841-9.
Baptista R, Santiago I, Jorge E, Teixeira R, Mendes P, Curvo-Semedo L, et al
. One-shot diagnostic and prognostic assessment in intermediate-to high-risk acute pulmonary embolism: The role of detector computed tomography. Rev Port Cardiol 2013;32:7-13.
Trujillo-Santos J, den Exter PL, Gómez V, Del Castillo H, Moreno C, van der Hulle T, et al
. Computed tomography- assessed right ventricular dysfunction and risk stratification of patients with acute non-massive pulmonary embolism: Systematic review and meta-analysis. J Thromb Haemost 2013;11:1823-32.
Wu AS, Pezzullo JA, Cronan JJ, Hou DD, Mayo-Smith WW. CT pulmonary angiography: Quantification of pulmonary embolus as a predictor of patient outcome - initial experience. Radiology 2004;230:831-5.
Rodrigues B, Correia H, Figueiredo A, Delgado A, Moreira D, Ferreira Dos Santos L, et al
. Clot burden score in the evaluation of right ventricular dysfunction in acute pulmonary embolism: Quantifying the cause and clarifying the consequences. Rev Port Cardiol 2012;31:687-95.
Zhou Y, Shi H, Wang Y, Kumar AR, Chi B, Han P. Assessment of correlation between CT angiographic clot load score, pulmonary perfusion defect score and global right ventricular function with dual-source CT for acute pulmonary embolism. Br J Radiol 2012;85:972-9.
Furlan A, Aghayev A, Chang CC, Patil A, Jeon NK, Park B, et al
. Short-term mortality in acute pulmonary embolism: Clot burden and signs of right heart dysfunction at CT pulmonary angiography. Radiology 2012;265:283-93.
Aviram G, Rosowski O, Gotler Y, Bendler A, Steinvil A, Goldin Y, et al
. Real-time risk stratification of patients with acute pulmonary embolism by grading the reflux of contrast into the inferior vena cava on computerized tomographic pulmonary angiography. J Thromb Haemost 2008;6:1488-93.
Coutance G, Cauderlier E, Ehtisham J, Hamon M, Hamon M. The prognostic value of markers of right ventricular dysfunction in pulmonary embolism: A meta-analysis. Crit Care 2011;15:R103.
Alonso-Martínez JL, Urbieta-Echezarreta M, Anniccherico-Sánchez FJ, Abínzano-Guillen ML, García-Sanchotena JL. N-terminal Pro-B-type natriuretic peptide predicts the burden of pulmonary embolism. Am J Med Sci 2009;337:88-92.
Konstantinidis SV, Torbicki A, Agnelli G, Danchin N, Fitzmaurice D, Galie N, et al
.; Task Force for the Diagnosis and Management of Acute Pulmonary Embolism of the European Society of Cardiology (ESC). 2014 ESC guidelines on the diagnosis and management of acute pulmonary embolism. Eur Heart J 2014;35:3033-69, 3069a-3069k.
Kolk FA, Djurabi RK, Nijkeuter M, Eikenboom HC, Leebeek FW, Kramer MH, et al
. High D-dimer level is associated with increased 15-d and 3-months mortality through a more central localization of pulmonary emboli and serious comorbidity. Br J Haematol 2008;140:218-22.
Venkatesh SK, Wang SC. Central clot score at computed tomography as a predictor of 30 day mortality after acute pulmonary embolism. Ann Acad Med Singapore 2010;39:442-7.
Donato AA, Khoche S, Santora J, Wagner B. Clinical outcomes in patients with isolated subsegmental pulmonary emboli diagnosed by multidetector CT pulmonary angiography. Thromb Res 2010;126:e266-70.
Vedovati MC, Becattini C, Agnelli G, Kamphuisen PW, Masotti L, Pruszczyk P, et al
. Multidetector CT scan for acute pulmonary embolism: Embolic burden and clinical outcome. Chest 2012;142:1407-24.
Nakada K, Okada T, Osada H, Honda N. Relation between pulmonary embolus volume quantified by multidetector computed tomography and clinical status and outcome for patients with acute pulmonary embolism. Jpn J Radiol 2010;28:34-42.
Ceylan N, Tasbakan S, Bayraktaroglu S, Cok G, Simsek T, Duman S, et al
. Predictors of clinical outcome in acute pulmonary embolism: Correlation of CT pulmonary angiography with clinical, echocardiography and laboratory findings. Acad Radiol 2011;18:47-53.
Soares TH, de Bastos M, de Carvalho BV, Moreira W, Cabral CP, de Paula LF, et al
. Prognostic value of computed tomographic pulmonary angiography and the pulmonary embolism severiti index in patients with acute pulmonary embolism. Blood Coagul Fibinolysis 2013;24:64-70.
Elliott CG. Fibrinolysis of pulmonary emboli - steer closer to Scylla. N Engl J Med 2014;370:1457-8.
Vedovati MC, Germin F, Agnelli G, Becattini C. Prognostic role of embolic burden assessed at computed tomography angiography in patients with acute pulmonary embolism: Systematic review and meta-analysis. J Thromb Haemost 2013;11:2092-102.
Meinell FG, Nance JW, Schoepf UJ, Hoffmann VS, Thierfelder KM, Costello P, et al
. Predictive value of computed tomography in acute pulmonary embolism: Systematic review and meta-analysis. Am J Med 2015;128:747-59.e2.
Qanadli SD, El Hajjam M, Vieillard-Baron A, Joseph T, Mesurolle B, Oliva VL, et al
. New CT index to quantify arterial obstruction in pulmonary embolism: Comparison with angiographic index and echocardiography. AJR Am J Roentgenol 2001;176:1415-20.
Leurs PB, Stolk RP, Hamulyak K, Van Oerle R, Grobbee DE, Wolffenbuttel BH. Tissue factor pathway inhibitor and other endothelium-dependent hemostatic factors in elderly individuals with normal or impaired glucose tolerance and type-2 diabetes. Diabetes Care 2002;25:1340-5.
Aujesky D, Obrosky DS, Stone RA, Auble TE, Perrier A, Cornuz J, et al
. A prediction rule to identify low-risk patients with pulmonary embolism. Arc Intern Med 2006;166:169-75.
Laporte S, Mismetti P, Décousus H, Uresandi F, Otero R, Lobo JL, et al
. Clinical predictors for fatal pulmonary embolism in 15,520 patients with venous thromboembolism: Findings from the Registro Informatizado de la Enfermedad Tromboembólica Venosa (RIETE) Registry. Circulation 2008;117:1711-6.
Goldhaber SZ, Visani L, De Rosa M. Acute pulmonary embolism: Clinical outcomes in the international Cooperative Pulmonary Embolism Registry (ICOPER). Lancet 1999;353:1386-9.
Carrier M, Le Gal G, Wells PS, Rodger MA. Systematic review: Case-fatality rates of recurrent venous thromboembolism and major bleeding events among patients treated for venous thromboembolism. Ann Intern Med 2010;152:578-89.
[Table 1], [Table 2], [Table 3], [Table 4]
|This article has been cited by|
||Risk Factor and Mortality in Patients with Pulmonary Embolism Combined with Infectious Disease
| ||Gi Dong Lee,Sunmi Ju,Ju-Young Kim,Tae Hoon Kim,Jung-Wan Yoo,Seung Jun Lee,Yu Ji Cho,Yi Yeong Jeong,Kyung Nyeo Jeon,Jong Deog Lee,Ho Cheol Kim |
| ||Tuberculosis and Respiratory Diseases. 2020; 83(2): 157 |
|[Pubmed] | [DOI]|
||To Use or Not Use Patient Shielding on Pregnant Women Undergoing CT Pulmonary Angiography: A Phantom Study
| ||Dino Begano,Marcus Söderberg,Anetta Bolejko |
| ||Radiation Protection Dosimetry. 2020; |
|[Pubmed] | [DOI]|
||Impact of concomitant deep or superficial venous thrombosis of the legs on survival of patients with pulmonary embolism
| ||Karsten Keller,Lukas Hobohm,Thomas Münzel,Mir A. Ostad |
| ||International Journal of Cardiology. 2020; |
|[Pubmed] | [DOI]|
||Pulmonary Vessel Obstruction Does Not Correlate with Severity of Pulmonary Embolism
| ||Marianne Lerche,Nikolaos Bailis,Mideia Akritidou,Hans Jonas Meyer,Alexey Surov |
| ||Journal of Clinical Medicine. 2019; 8(5): 584 |
|[Pubmed] | [DOI]|
||Diagnosis and treatment of subsegmental pulmonary embolism
| ||Michael Newnham,Alice M Turner |
| ||World Journal of Respirology. 2019; 9(3): 30 |
|[Pubmed] | [DOI]|
||Radiology report annotation using intelligent word embeddings: Applied to multi-institutional chest CT cohort
| ||Imon Banerjee,Matthew C. Chen,Matthew P. Lungren,Daniel L. Rubin |
| ||Journal of Biomedical Informatics. 2018; 77: 11 |
|[Pubmed] | [DOI]|
||D-Dimer and thrombus burden in acute pulmonary embolism
| ||Karsten Keller,Johannes Beule,Jörn Oliver Balzer,Wolfgang Dippold |
| ||The American Journal of Emergency Medicine. 2018; |
|[Pubmed] | [DOI]|
||Virtual Monoenergetic Imaging and Iodine Perfusion Maps Improve Diagnostic Accuracy of Dual-Energy Computed Tomography Pulmonary Angiography With Suboptimal Contrast Attenuation
| ||Doris Leithner,Julian L. Wichmann,Thomas J. Vogl,Jesko Trommer,Simon S. Martin,Jan-Erik Scholtz,Boris Bodelle,Carlo N. De Cecco,Taylor Duguay,John W. Nance,U. Joseph Schoepf,Moritz H. Albrecht |
| ||Investigative Radiology. 2017; 52(11): 659 |
|[Pubmed] | [DOI]|
||Thromboembolectomy combined with coronary artery bypass grafting in acute period of pulmonary embolism
| ||A. N. Kazantsev,R. S. Tarasov,M. G. Zinec,A. I. Anufriev,N. N. Burkov,E. V. Grigoriev |
| ||Kardiologiya i serdechno-sosudistaya khirurgiya. 2017; 10(6): 93 |
|[Pubmed] | [DOI]|
||The relation between international normalized ratio and mortality in acute pulmonary embolism: A retrospective study
| ||Tuncay Kiris,Selcuk Yazici,Gündüz Durmus,Yigit Çanga,Mustafa Karaca,Cem Nazli,Abdullah Dogan |
| ||Journal of Clinical Laboratory Analysis. 2017; : e22164 |
|[Pubmed] | [DOI]|