MEDLINE Abstracts: Acute Pulmonary Embolism: Diagnostic Strategies
MEDLINE Abstracts: Acute Pulmonary Embolism: Diagnostic Strategies
What's new concerning the diagnostic approach to acute pulmonary embolism? Find out in this easy-to-navigate collection of recent MEDLINE abstracts compiled by the editors at Medscape Pulmonary Medicine.
Anonymous
Chest 113(2):499-504, 1998 Feb
Purpose: The purpose of this consensus report was to address clinically relevant questions related to the diagnosis and management of acute pulmonary embolism and deep venous thrombosis.
Background: Physicians are often forced to make decisions about the diagnosis and management of pulmonary thromboembolism even though there are only limited data to guide them.
Methods: We assessed the relevant literature regarding clinical trials according to levels of evidence. The data on which the opinions of the committee were made were sparse. The consensus opinions, therefore, were often based on experience or intuition, rather than firm data.
Results: Consensus opinions were given in regard to eight clinically relevant questions.
Conclusion: We hope that the consensus opinions of this committee will assist others in making clinical decisions while we all await prospective investigations.
Corris PA
Hospital Medicine 59(5):369-71, 1998 May
Pulmonary embolism (PE) is both under- and over-diagnosed, which leads to patients either failing to receive treatment or receiving unnecessary potentially life-threatening treatment. Rational diagnosis and management of suspected PE is now possible, but much current practice is unsatisfactory. This article gives practical, evidence-based guidelines for the clinical diagnosis of PE.
Rubboli A, Leonardi G, de Castro U, Bracchetti D
Giornale Italiano di Cardiologia 28(2):123-30, 1998 Feb
Background: Several approaches have been proposed for the diagnosis of acute pulmonary embolism (PE), but little is known about the strategies effectively used in daily clinical practice.
Methods: Retrospective evaluation of the diagnostic strategy used in our institution in the patients (pts) discharged between January 1st 1995 and December 31st 1996 with diagnostic code 415.1, corresponding to acute PE in the International Classification of Disease.
Results: One-hundred-twenty-seven patients (49 M; 78 F; mean age: 71.5 +/- 15 years; range: 25-95) were identified. Electrocardiogram, chest X-ray, blood gas analysis and plasma D-dimer measurement were performed in 122 (96%), 121 (95%), 114 (90%) and 86 (68%) pts, respectively. Out of the 102 pts surviving the initial phase (early mortality: 20%), 83 (81%) underwent lung scintigraphy, 10 (10%) spiral CT scanning and 2 (2%) pulmonary angiography, while 7 (7%) were treated directly. Thirty of the 83 pts undergoing lung scintigraphy had non-diagnostic results, but only 8 of them underwent further investigation (with spiral CT in 6 cases and pulmonary angiography in 2 cases). Transthoracic echocardiography and ultrasonography of the lower limbs were used in 49 (48%) and 74 (73%) pts respectively, for diagnostic confirmation and to search for the embolic source.
Conclusions: At our institution, where multiple and modern diagnostic facilities are available, ventilation/perfusion lung scanning still represents the most frequently used imaging technique. Spiral CT is employed quite often as an alternative to either lung scintigraphy or pulmonary angiography which, in turn, is used very seldom. Ultrasonography of the lower-limbs is widely utilized (although not in a serial manner and only as a second-line test), while the role of echocardiography appears to be marginal. Spiral CT, pulmonary angiography and lower-limb ultrasonography showed high diagnostic accuracy, while the accuracy of lung scintigraphy and echocardiography was confirmed as being suboptimal. However, due to the retrospective design of our study and the characteristics of our population, these results cannot be extrapolated to pts referred for suspected acute PE, in whom further investigations are thus warranted in order to identify the most cost-effective diagnostic approach.
Jones JS, Neff TL, Carlson SA
American Journal of Emergency Medicine 16(4):333-7, 1998 Jul
To evaluate the utility of the alveolar-arterial (A-a) oxygen gradient in the diagnosis of acute pulmonary embolism (PE), a retrospective analysis was done of consecutive emergency department patients who underwent pulmonary angiography for the presumed diagnosis of acute PE. Patients were categorized into two groups depending on the presence or absence of prior cardiopulmonary disease. Arterial blood gas samples were chosen for analysis only if obtained when the PE first was suspected clinically (before lung scans or angiograms) and the patient was breathing room air. A total of 152 patients met all study criteria; 59 patients (39%) had angiographically documented emboli. In comparison with the study patients in whom PE was excluded, there was no significant difference in mean PaO2 (64 v 67 mm Hg) or A-a gradient (39 v 36 mm Hg). Various combinations of the A-a gradient and blood gas levels failed to exclude PE in more than 35% of patients with no prior cardiovascular disease and in 25% of patients with prior cardiovascular disease. The A-a gradient did show a linear correlation with the severity of the PE, as assessed by the PaO2 (r = -0.87) and pulmonary artery mean pressure (r = 0.63). These results indicate that the A-a oxygen gradient, in combination with blood gas levels, may contribute to the formulation of a clinical assessment. However, these laboratory parameters are of insufficient discriminant value to permit exclusion of the diagnosis of PE.
Coche EE, Muller NL, Kim KI, Wiggs BR, Mayo JR
Radiology 207(3):753-8, 1998 Jun
Purpose: To determine the value of parenchymal findings at contrast material-enhanced spiral computed tomography (CT) in patients suspected to have pulmonary embolism (PE).
Materials and Methods: Eighty-eight patients suspected to have PE underwent contrast-enhanced spiral CT and ventilation-perfusion scintigraphy. Concordance between CT and scintigraphic results was used to diagnose or exclude PE. Pulmonary angiography was attempted in all patients with discordant CT and scintigraphic results or indeterminate scans. Parenchymal CT scans were assessed by two radiologists who were not aware of the diagnosis and who had access only to lung window images.
Results: Twenty-six patients had PE; 62 did not. Wedge-shaped pleural-based consolidation was seen in 16 patients with PE (62%) and 17 patients without PE (27%) (P < .05) (sensitivity, 62%; specificity, 73%). Linear bands were seen in 12 patients with PE (46%) and 13 patients without PE (21%) (P < .05) (sensitivity, 46%; specificity, 79%). There was no statistically significant difference in the frequency of non-wedge-shaped consolidation, areas of decreased attenuation, or atelectasis. Central and lower-lobe segmental pulmonary arteries that contained emboli were enlarged (P < .05).
Conclusion: Parenchymal findings may suggest further investigations when results of spiral CT are inconclusive in diagnosis of PE.
Bankier A, Herold CJ, Fleischmann D, Janata-Schwatczek K
Radiologe 38(4):248-55, 1998 Apr
Purpose: Debate about the potential implementation of Spiral-CT in diagnostic algorithms of pulmonary embolism are often focussed on sensitivity and specificity in the context of comparative methodologic studies. We intend to investigate whether additional factors might influence this debate.
Materials and Methods: On the basis of the current literature and of own experience we study the influence of factors such as availability, acceptance, patient-outcome, and cost effectiveness-studies on the potential implementation of Spiral-CT in diagnostic algorithms of pulmonary embolism. This information is analyzed together with data from comparative methodologic studies.
Results: The factors availability, acceptance, patient-outcome, and cost-effectiveness-studies do have substantial influence on the implementation of Spiral-CT in the diagnostic algorithms of pulmonary embolism. Incorporation of these factors into the discussion might lead to more flexible and more patient-oriented algorithms for the diagnosis of pulmonary embolism.
Conclusion: Availability of equipment, acceptance among clinicians, patient-outcome, and cost-effectiveness evaluations should be implemented into the debate about potential implementation of Spiral-CT in routine diagnostic imaging algorithms of pulmonary embolism.
Roberts HC, Kauczor HU, Pitton MB, Schweden F, Thelen M
Rofo. Fortschritte auf dem Gebiete der Rontgenstrahlen und der Neuen Bildgebenden Verfahren 166(6):463-74, 1997 Jun
Acute pulmonary embolism (PE) is an increasing and underdiagnosed cause of mortality and morbidity in hospitalised patients: pulmonary hypertension based on chronic pulmonary embolism is an uncommon, but severe and surgically curable complication. Since clinical signs might be silent or unspecific, both acute and chronic PE require imaging methods for diagnosis and treatment planning. Chest radiographic findings are usually non-specific. Scintigraphy provides a high sensitivity for PE, but lacks anatomic resolution and sufficient specificity. Pulmonary angiography, albeit accurate, is an invasive procedure associated with low but still not negligible morbidity and mortality. Hence, non-invasive methods offer advantages. Spiral CT, for example, is most reliable in the diagnosis of acute and chronic PE: Such fast CT techniques provide a non-invasive means to detect and differentiate acute emboli and organised thrombi, as well as perfusion abnormalities and other concomitant findings. MRI offers both morphological and functional information on lung perfusion and right heart function, but its image quality still needs improvement to be comparable with CT. Thus, while MRI must still be tested in clinical studies. CT is recommended as a screening method in acute and chronic pulmonary embolism.
Miller RL, Das S, Anandarangam T, Leibowitz DW, Alderson PO, Thomashow B, Homma S
Chest 113(3):665-70, 1998 Mar
Background/Objectives: Patients presenting with acute pulmonary embolism associated with hemodynamic compromise exhibit right ventricular enlargement and dysfunction on transthoracic echocardiogram. However, the degree of echocardiographic abnormalities among hemodynamically stable patients without preexisting cardiopulmonary disease during the acute stage of pulmonary embolism, and following treatment, is unknown. Therefore, this study was designed to assess the extent of right ventricular abnormalities detected on transthoracic echocardiogram in patients following acute pulmonary embolism and during treatment with anticoagulation or vena caval interruption. The extent of pulmonary vascular obstruction and complication rate on follow-up were also assessed.
Design/Interventions: Sixty-four consecutive hemodynamically stable patients without preexisting known cardiopulmonary disorder presenting with acute pulmonary embolism and undergoing treatment with anticoagulation or inferior vena caval interruption were studied. All subjects underwent a two-dimensional transthoracic echocardiogram within 24 h of diagnosis. The degree of perfusion abnormality on lung scan was quantified. Twenty-six patients underwent follow-up echocardiogram and lung scan at 6 weeks. The echocardiographic findings were compared with those obtained from a group of normal control subjects matched for gender and age.
Results: Although the mean right ventricular end-diastolic areas did not differ (21.9+/-5.2 cm2 vs 20.1+/-2.9 cm2 for control subjects; p=not significant), the right ventricular end-systolic area was larger in comparison to our series of control subjects (14.6+/-5.1 cm2 vs 11.7+/-2.0 cm2; p=0.025). Fractional right ventricular area change was reduced in the patient group compared with the control subjects (34.3+/-9.0% vs 41.3+/-7.0%; p=0.003). The extent of right ventricular end-systolic area enlargement and decrease in fractional area change did not correlate with the degree of pulmonary vascular obstruction. Patients who were restudied at 6 weeks showed minimal improvement in echocardiographic findings, despite almost complete resolution of perfusion defects on lung scan.
Conclusions: The extent of right ventricular dysfunction in hemodynamically stable, previously normal patients with acute pulmonary embolism does not reflect the extent of the perfusion abnormalities. Further, right ventricular enlargement and systolic dysfunction are present and persistent despite treatment with heparin and warfarin therapy or vena caval interruption.
What's new concerning the diagnostic approach to acute pulmonary embolism? Find out in this easy-to-navigate collection of recent MEDLINE abstracts compiled by the editors at Medscape Pulmonary Medicine.
Anonymous
Chest 113(2):499-504, 1998 Feb
Purpose: The purpose of this consensus report was to address clinically relevant questions related to the diagnosis and management of acute pulmonary embolism and deep venous thrombosis.
Background: Physicians are often forced to make decisions about the diagnosis and management of pulmonary thromboembolism even though there are only limited data to guide them.
Methods: We assessed the relevant literature regarding clinical trials according to levels of evidence. The data on which the opinions of the committee were made were sparse. The consensus opinions, therefore, were often based on experience or intuition, rather than firm data.
Results: Consensus opinions were given in regard to eight clinically relevant questions.
Conclusion: We hope that the consensus opinions of this committee will assist others in making clinical decisions while we all await prospective investigations.
Corris PA
Hospital Medicine 59(5):369-71, 1998 May
Pulmonary embolism (PE) is both under- and over-diagnosed, which leads to patients either failing to receive treatment or receiving unnecessary potentially life-threatening treatment. Rational diagnosis and management of suspected PE is now possible, but much current practice is unsatisfactory. This article gives practical, evidence-based guidelines for the clinical diagnosis of PE.
Rubboli A, Leonardi G, de Castro U, Bracchetti D
Giornale Italiano di Cardiologia 28(2):123-30, 1998 Feb
Background: Several approaches have been proposed for the diagnosis of acute pulmonary embolism (PE), but little is known about the strategies effectively used in daily clinical practice.
Methods: Retrospective evaluation of the diagnostic strategy used in our institution in the patients (pts) discharged between January 1st 1995 and December 31st 1996 with diagnostic code 415.1, corresponding to acute PE in the International Classification of Disease.
Results: One-hundred-twenty-seven patients (49 M; 78 F; mean age: 71.5 +/- 15 years; range: 25-95) were identified. Electrocardiogram, chest X-ray, blood gas analysis and plasma D-dimer measurement were performed in 122 (96%), 121 (95%), 114 (90%) and 86 (68%) pts, respectively. Out of the 102 pts surviving the initial phase (early mortality: 20%), 83 (81%) underwent lung scintigraphy, 10 (10%) spiral CT scanning and 2 (2%) pulmonary angiography, while 7 (7%) were treated directly. Thirty of the 83 pts undergoing lung scintigraphy had non-diagnostic results, but only 8 of them underwent further investigation (with spiral CT in 6 cases and pulmonary angiography in 2 cases). Transthoracic echocardiography and ultrasonography of the lower limbs were used in 49 (48%) and 74 (73%) pts respectively, for diagnostic confirmation and to search for the embolic source.
Conclusions: At our institution, where multiple and modern diagnostic facilities are available, ventilation/perfusion lung scanning still represents the most frequently used imaging technique. Spiral CT is employed quite often as an alternative to either lung scintigraphy or pulmonary angiography which, in turn, is used very seldom. Ultrasonography of the lower-limbs is widely utilized (although not in a serial manner and only as a second-line test), while the role of echocardiography appears to be marginal. Spiral CT, pulmonary angiography and lower-limb ultrasonography showed high diagnostic accuracy, while the accuracy of lung scintigraphy and echocardiography was confirmed as being suboptimal. However, due to the retrospective design of our study and the characteristics of our population, these results cannot be extrapolated to pts referred for suspected acute PE, in whom further investigations are thus warranted in order to identify the most cost-effective diagnostic approach.
Jones JS, Neff TL, Carlson SA
American Journal of Emergency Medicine 16(4):333-7, 1998 Jul
To evaluate the utility of the alveolar-arterial (A-a) oxygen gradient in the diagnosis of acute pulmonary embolism (PE), a retrospective analysis was done of consecutive emergency department patients who underwent pulmonary angiography for the presumed diagnosis of acute PE. Patients were categorized into two groups depending on the presence or absence of prior cardiopulmonary disease. Arterial blood gas samples were chosen for analysis only if obtained when the PE first was suspected clinically (before lung scans or angiograms) and the patient was breathing room air. A total of 152 patients met all study criteria; 59 patients (39%) had angiographically documented emboli. In comparison with the study patients in whom PE was excluded, there was no significant difference in mean PaO2 (64 v 67 mm Hg) or A-a gradient (39 v 36 mm Hg). Various combinations of the A-a gradient and blood gas levels failed to exclude PE in more than 35% of patients with no prior cardiovascular disease and in 25% of patients with prior cardiovascular disease. The A-a gradient did show a linear correlation with the severity of the PE, as assessed by the PaO2 (r = -0.87) and pulmonary artery mean pressure (r = 0.63). These results indicate that the A-a oxygen gradient, in combination with blood gas levels, may contribute to the formulation of a clinical assessment. However, these laboratory parameters are of insufficient discriminant value to permit exclusion of the diagnosis of PE.
Coche EE, Muller NL, Kim KI, Wiggs BR, Mayo JR
Radiology 207(3):753-8, 1998 Jun
Purpose: To determine the value of parenchymal findings at contrast material-enhanced spiral computed tomography (CT) in patients suspected to have pulmonary embolism (PE).
Materials and Methods: Eighty-eight patients suspected to have PE underwent contrast-enhanced spiral CT and ventilation-perfusion scintigraphy. Concordance between CT and scintigraphic results was used to diagnose or exclude PE. Pulmonary angiography was attempted in all patients with discordant CT and scintigraphic results or indeterminate scans. Parenchymal CT scans were assessed by two radiologists who were not aware of the diagnosis and who had access only to lung window images.
Results: Twenty-six patients had PE; 62 did not. Wedge-shaped pleural-based consolidation was seen in 16 patients with PE (62%) and 17 patients without PE (27%) (P < .05) (sensitivity, 62%; specificity, 73%). Linear bands were seen in 12 patients with PE (46%) and 13 patients without PE (21%) (P < .05) (sensitivity, 46%; specificity, 79%). There was no statistically significant difference in the frequency of non-wedge-shaped consolidation, areas of decreased attenuation, or atelectasis. Central and lower-lobe segmental pulmonary arteries that contained emboli were enlarged (P < .05).
Conclusion: Parenchymal findings may suggest further investigations when results of spiral CT are inconclusive in diagnosis of PE.
Bankier A, Herold CJ, Fleischmann D, Janata-Schwatczek K
Radiologe 38(4):248-55, 1998 Apr
Purpose: Debate about the potential implementation of Spiral-CT in diagnostic algorithms of pulmonary embolism are often focussed on sensitivity and specificity in the context of comparative methodologic studies. We intend to investigate whether additional factors might influence this debate.
Materials and Methods: On the basis of the current literature and of own experience we study the influence of factors such as availability, acceptance, patient-outcome, and cost effectiveness-studies on the potential implementation of Spiral-CT in diagnostic algorithms of pulmonary embolism. This information is analyzed together with data from comparative methodologic studies.
Results: The factors availability, acceptance, patient-outcome, and cost-effectiveness-studies do have substantial influence on the implementation of Spiral-CT in the diagnostic algorithms of pulmonary embolism. Incorporation of these factors into the discussion might lead to more flexible and more patient-oriented algorithms for the diagnosis of pulmonary embolism.
Conclusion: Availability of equipment, acceptance among clinicians, patient-outcome, and cost-effectiveness evaluations should be implemented into the debate about potential implementation of Spiral-CT in routine diagnostic imaging algorithms of pulmonary embolism.
Roberts HC, Kauczor HU, Pitton MB, Schweden F, Thelen M
Rofo. Fortschritte auf dem Gebiete der Rontgenstrahlen und der Neuen Bildgebenden Verfahren 166(6):463-74, 1997 Jun
Acute pulmonary embolism (PE) is an increasing and underdiagnosed cause of mortality and morbidity in hospitalised patients: pulmonary hypertension based on chronic pulmonary embolism is an uncommon, but severe and surgically curable complication. Since clinical signs might be silent or unspecific, both acute and chronic PE require imaging methods for diagnosis and treatment planning. Chest radiographic findings are usually non-specific. Scintigraphy provides a high sensitivity for PE, but lacks anatomic resolution and sufficient specificity. Pulmonary angiography, albeit accurate, is an invasive procedure associated with low but still not negligible morbidity and mortality. Hence, non-invasive methods offer advantages. Spiral CT, for example, is most reliable in the diagnosis of acute and chronic PE: Such fast CT techniques provide a non-invasive means to detect and differentiate acute emboli and organised thrombi, as well as perfusion abnormalities and other concomitant findings. MRI offers both morphological and functional information on lung perfusion and right heart function, but its image quality still needs improvement to be comparable with CT. Thus, while MRI must still be tested in clinical studies. CT is recommended as a screening method in acute and chronic pulmonary embolism.
Miller RL, Das S, Anandarangam T, Leibowitz DW, Alderson PO, Thomashow B, Homma S
Chest 113(3):665-70, 1998 Mar
Background/Objectives: Patients presenting with acute pulmonary embolism associated with hemodynamic compromise exhibit right ventricular enlargement and dysfunction on transthoracic echocardiogram. However, the degree of echocardiographic abnormalities among hemodynamically stable patients without preexisting cardiopulmonary disease during the acute stage of pulmonary embolism, and following treatment, is unknown. Therefore, this study was designed to assess the extent of right ventricular abnormalities detected on transthoracic echocardiogram in patients following acute pulmonary embolism and during treatment with anticoagulation or vena caval interruption. The extent of pulmonary vascular obstruction and complication rate on follow-up were also assessed.
Design/Interventions: Sixty-four consecutive hemodynamically stable patients without preexisting known cardiopulmonary disorder presenting with acute pulmonary embolism and undergoing treatment with anticoagulation or inferior vena caval interruption were studied. All subjects underwent a two-dimensional transthoracic echocardiogram within 24 h of diagnosis. The degree of perfusion abnormality on lung scan was quantified. Twenty-six patients underwent follow-up echocardiogram and lung scan at 6 weeks. The echocardiographic findings were compared with those obtained from a group of normal control subjects matched for gender and age.
Results: Although the mean right ventricular end-diastolic areas did not differ (21.9+/-5.2 cm2 vs 20.1+/-2.9 cm2 for control subjects; p=not significant), the right ventricular end-systolic area was larger in comparison to our series of control subjects (14.6+/-5.1 cm2 vs 11.7+/-2.0 cm2; p=0.025). Fractional right ventricular area change was reduced in the patient group compared with the control subjects (34.3+/-9.0% vs 41.3+/-7.0%; p=0.003). The extent of right ventricular end-systolic area enlargement and decrease in fractional area change did not correlate with the degree of pulmonary vascular obstruction. Patients who were restudied at 6 weeks showed minimal improvement in echocardiographic findings, despite almost complete resolution of perfusion defects on lung scan.
Conclusions: The extent of right ventricular dysfunction in hemodynamically stable, previously normal patients with acute pulmonary embolism does not reflect the extent of the perfusion abnormalities. Further, right ventricular enlargement and systolic dysfunction are present and persistent despite treatment with heparin and warfarin therapy or vena caval interruption.