Clinical Suspicion Of Acute Pulmonary Embolism Research Articles

Comparison of Dual-Energy Computed Tomography Pulmonary Angiography-Derived Contrast Enhancement with Standard Dual-Energy Pulmonary Angiography in Diagnosing Subsegmental Pulmonary Embolism: A Prospective Study.

Objective In this study, we compare the diagnostic accuracy of dual-energy (DE) computed tomography pulmonary angiography (CTPA) derived contrast enhancement (DECTPA, CTPA images with iodine maps) with standard dual-energy pulmonary angiography (SCTPA) for diagnosis of subsegmental pulmonary embolism in the cases with clinical suspicion of acute pulmonary embolism (APE). Materials and Methods We included 50 cases with clinical suspicion of APE that were referred for CTPA. All the patients underwent CTPA in the dual-energy protocol. Two radiologists evaluated the images. The first radiologist interpreted the SCTPA images (vascular images) and the second radiologist interpreted the DECTPA (CTPA images with iodine maps) for findings of APE. We calculated the sensitivity, specificity, and negative predictive value of DECTPA vis-à-vis SCTPA images. Results The DECTPA with the advantage of iodine map utilization yielded higher detection of thrombi in peripheral subsegmental arteries (72 vs. 99; p = - 0.001) as compared to the SCTPA images by identification of 18 new perfusion defects (interquartile range [IQR]: 0-1) that were consistent with APE. Filling defects were identified in 27 (IQR: 0-4) more subsegmental arteries supplying these 18 areas, which were not detected on SCTPA alone. These 18 perfusion defects were identified in 13 cases. In these 13 cases, 4 new cases were diagnosed that were negative on CTPA ( p = -0.125). In the evaluation of the APE, sensitivity and specificity were calculated and it was found that DECTPA showed 100% sensitivity and 86% specificity with 100% negative predictive value in the detection of thrombi as compared to the routine CTPA. Conclusion DECTPA has higher sensitivity and negative predictive value in the detection of the subsegmental perfusion defect identification as compared to SCTPA.

Acute Pulmonary Embolism Severity Assessment Evaluated with Dual Energy CT Perfusion Compared to Conventional CT Angiographic Measurements

The purpose of the study was to investigate whether Dual Energy CT (DECT) can be used as a diagnostic tool to assess the severity of acute pulmonary embolism (PE) by correlating parenchymal perfusion defect volume, obstruction score and right ventricular-to-left ventricular (RV/LV) diameter ratio using CT angiography (CTA) and DECT perfusion imaging. A total of 43 patients who underwent CTA and DECT perfusion imaging with clinical suspicion of acute PE were retrospectively included in the study. In total, 25 of these patients had acute PE findings on CTA. DECT assessed perfusion defect volume (PDvol) were automatically and semiautomatically quantified. Overall, two CTA methods for risk assessment in patients with acute PE were assessed: the RV/LV diameter ratio and the Modified Miller obstruction score. Automatic PDvol had a weak correlation (r = 0.47, p = 0.02) and semiautomatic PDvol (r = 0.68, p < 0.001) had a moderate correlation to obstruction score in patients with confirmed acute PE, while only semiautomatic PDvol (r = 0.43, p = 0.03) had a weak correlation with the RV/LV diameter ratio. Our data indicate that PDvol assessed by DECT software technique may be a helpful tool to assess the severity of acute PE when compared to obstruction score and RV/LV diameter ratio.

Importance of computed tomography pulmonary angiography for predict 30-day mortality in acute pulmonary embolism patients

ObjectiveThe purpose of the present study was to assess the implications of different parameters of computed tomography pulmonary angiography (CTPA) to predict 30-day mortality in acute pulmonary embolism (APE) patients. Material and MethodPatients who had clinical suspicion of APE and underwent CTPA were recruited in a retrospective cohort study. The findings of the CTPA included the parameters of right ventricular dysfunction (RVD), the severity of obstruction to the pulmonary artery by CT obstruction index, and the ratio of pulmonary trunk diameter and aorta. The endpoint of the study was established as the 30-day mortality associated with APE. ResultsA total of 238 patients with a confirmed APE diagnosis with CTPA were included in the study; 26 (10.9 %) of those patients died within 30 days. In patients with cancer and the Pulmonary Embolism Severity Index (PESI) class 5, the mortality rate was significantly higher. Compared with survivors, the mean CT obstruction index in the non-survivor group was significantly higher (p < 0.001). Higher mortality was associated with all RVD parameters identified by CTPA, such as the RV/LV ratio (p < 0.001), interventricular septum deviation grade 3 (p < 0.001), increased RV diameter (p < 0.001), and IVC contrast reflux (p < 0.001). The highest adjusted odds ratio was RV diameter at 1.094, followed by PESI and the CT obstruction index at 1.040. ConclusionCTPA-detected RVD parameters and CT obstruction index can predict a 30-day mortality rate in APE patients and be used for risk stratification. In APE patients, the RV diameter of 53 mm or greater and the CT obstruction index >70% is associated with increased 30-day mortality.

A comparative analysis of the diagnostic performances of four clinical probability models for acute pulmonary embolism in a sub-Saharan African population: a cross-sectional study

BackgroundThe diagnosis of acute pulmonary embolism (PE) is one of the most challenging in emergency settings where prompt and accurate decisions need to be taken for life-saving purposes. Here, the assessment of the clinical probability of PE is a paramount step in its diagnosis. Although clinical probability models (CPM) for PE are routinely used in emergency departments (EDs) of low-resource settings, few studies have cited their diagnostic performances in sub-Saharan Africa (SSA). We aimed to comparatively assess the accuracy of four CPM in the diagnosis of acute PE in sub-Saharan Africans.MethodsWe carried out a cross-sectional study to compare the sensitivity, specificity, positive and negative predictive values and accuracy of four CPM namely; the Wells, simplified Wells, revised Geneva and the simplified revised Geneva (SRG) Scores to computed tomography pulmonary angiography (CTPA) in all adults patients with suspected PE admitted to the EDs of the Gynaeco-obstetric and Paediatric Hospital of Yaoundé and the Yaoundé Central Hospital in Cameroon between January 1, 2017 and April 30, 2018.ResultsIn total, we enrolled 30 patients with clinical suspicion of acute PE. PE was confirmed on CTPA in 16 (53.3%) cases. Their mean age was 53.7 ± 15.5 years and 36.7% were males. All four scores had a diagnostic performance superior to 50% in all criteria assessed. The simplified Wells score had the highest sensitivity (62.5%) followed by the Wells score (56.3%). The SRG score had the highest specificity (71.4%). The score with highest PPV was the SRG score (66.7%) and that with the highest NPV was the Wells score (56.3%). Overall the models with the highest accuracies were the Wells and SRG scores (60% for each).ConclusionAll CPM had a suboptimal diagnostic performance, perhaps highlighting the need of a more optimal CPM for acute PE in SSA. However, the Wells and the SRG scores appeared to be most accurate than the other two scores in the ED. Hence, both or either of them may be used in first intention to predict PE and guide which ED patients should undergo further investigations in an emergency SSA setting.

Rationale and design of three observational, prospective cohort studies including biobanking to evaluate and improve diagnostics, management strategies and risk stratification in venous thromboembolism: the VTEval Project

IntroductionVenous thromboembolism (VTE) with its two manifestations deep vein thrombosis (DVT) and pulmonary embolism (PE) is a major public health problem. The VTEval Project aims to investigate numerous research questions...

Right Ventricular Isovolumic Acceleration in Acute Pulmonary Embolism

In this study, we examined the role of isovolumic acceleration (IVA) measured with right ventricle (RV) tissue Doppler imaging (TDI) to predict the presence of acute pulmonary embolism (APE) in hemodynamically stable patients with clinical suspicion of APE. This study included 25 hemodynamically stable (systolic blood pressure >90 mmHg) patients diagnosed with APE for the first time. Twenty-five subjects with similar demographic characteristics in whom APE was excluded due to preexisting clinical suspicion were also enrolled as the control group. All control group subjects were enrolled after proved to have no evidence of APE on imaging. Both groups were compared with respect to RV-IVA measured with TDI in addition to conventional echocardiographic parameters. Among the echocardiography parameters, only RV-IVA was impaired in patients with hemodynamically stable APE compared to controls (2.85 [1.37-6.42] m/sec(2) vs. 3.32 [2.24-6.52] m/sec(2) , respectively; P = 0.02). A receiver operating characteristic (ROC) analysis was performed to determine the RV-IVA value to predict clinically suspected APE. A cutoff level of 3.22 m/sec(2) had a sensitivity of 64% and a specificity of 60%; a cutoff level of 3.17 m/sec(2) had a sensitivity of 64% and a specificity of 64%; and a cutoff level of 3.10 m/sec(2) had a sensitivity of 60% and specificity of 64% (ROC area under curve: 0.691, 95% CI: 0.543-0.839, P = 0.02). Results of our study suggest that RV-IVA may be a useful parameter to detect subtle alterations in RV and may predict the presence of APE in hemodynamically stable patients.

Acute pulmonary embolism in the era of multi-detector CT: a reality in sub-Saharan Africa

BackgroundThe advantages of multi-detector computed tomography (MDCT) have made it the imaging modality of choice for some patients with suspected cardiothoracic disease, of which pulmonary embolism (PE) is an exponent. The aim of this study was to assess the incidence of PE in patients with clinical suspicion of acute PE using MDCT in a sub-Saharan setting, and to describe the demographic characteristics of these patients.MethodsConsecutive records of patients who underwent MDCT pulmonary angiography for suspected acute PE over a two-year period at the Radiology Department of a university-affiliated hospital were systematically reviewed. All MDCT pulmonary angiograms were performed with a 16-detector computed tomography (CT) scanner using real-time bolus tracking technique. Authorization for the study was obtained from the institutional authorities.ResultsForty-one MDCT pulmonary angiograms were reviewed of which 37 were retained. Of the 4 excluded studies, 3 were repeat angiograms and 1 study was not technically adequate. Twelve of 37 patients (32.4%) had CT angiograms that were positive for PE, of which 7 were males. The mean age of these patients was 47.6±10.5 years (age range from 33 to 65 years). Twenty five patients out of 37 (67.6%) had CT angiograms that were negative for PE. Eleven PE-positive patients (91.7%) had at least 1 identifiable thromboembolic risk factor whilst 5 PE-negative patients (20%) also had at least a thromboembolic risk factor. The relative risk of the occurrence of PE in patients with at least a thromboembolic risk factor was estimated at 14.4.ConclusionAcute PE is a reality in sub-Saharan Africa, with an increased likelihood of MDCT evidence in patients with clinical suspicion of PE who have at least a thromboembolic risk factor. The increasing availability of MDCT will help provide more information on the occurrence of PE in these settings.

Lung Perfusion with Dual-energy Multidetector-row CT (MDCT): Feasibility for the Evaluation of Acute Pulmonary Embolism in 117 Consecutive Patients

To investigate the accuracy of dual-energy computed tomography in the depiction of perfusion defects in patients with acute pulmonary embolism (PE). One hundred seventeen consecutive patients with clinical suspicion of acute PE underwent dual-energy multidetector computed tomographic (CT) angiography of the chest with a standard injection protocol. Two radiologists evaluated, by consensus, the presence of endoluminal clots on (1) transverse "diagnostic" scans (contiguous 1-mm-thick averaged images from tubes A and B) and (2) lung perfusion scans. Seventeen patients showed CT features of acute PE, with the depiction of 75 clots within the lobar (n = 15), segmental (n = 43) and subsegmental (n = 17) pulmonary arteries. A total of 17 clots were identified as complete filling defects (ie, obstructive clots), located within segmental (12 of 17) and subsegmental (5 of 17) arteries. Fourteen of the 17 obstructive clots were seen with the concurrent presence of corresponding perfusion defects, whereas cardiac motion and/or contrast-induced artifacts precluded the confident recognition of perfusion abnormalities in the remaining two segments and one subsegment. Four subsegmental perfusion defects were depicted without the visualization of endoluminal thrombi within the corresponding arteries. Perfusion defects were identified beyond five nonobstructive clots. Simultaneous information on the presence of endoluminal thrombus and lung perfusion impairment can be obtained with dual-energy computed tomography.

Computed tomography pulmonary embolism index for the assessment of survival in patients with pulmonary embolism

This study was an analysis of the correlation between pulmonary embolism (PE) and patient survival. Among 694 consecutive patients referred to our institution with clinical suspicion of acute PE who underwent CT pulmonary angiography, 188 patients comprised the study group: 87 women (46.3%, median age: 60.7; age range: 19-88 years) and 101 men (53.7%, median age: 66.9; age range: 21-97 years). PE was assessed by two radiologist who were blinded to the results from the follow-up. A PE index was derived for each set of images on the basis of the embolus size and location. Results were analyzed using logistic regression, and correlation with risk factors and patient outcome (survival or death) was calculated. We observed no significant correlation between the CTPE index and patient outcome (p = 0.703). The test of logistic regression with the sum of heart and liver disease or presence of cancer was significantly (p< 0.05) correlated with PE and overall patient outcome. Interobserver agreement showed a significant correlation rate for the assessment of the PE index (0.993; p< 0.001). In our study the CT PE index did not translate into patient outcome. Prospective larger scale studies are needed to confirm the predictive value of the index and refine the index criteria.

Reproducibility of multi-detector spiral computed tomography in detection of sub-segmental acute pulmonary embolism

The aim of this study was to evaluate the inter-observer and intra-observer agreement of the diagnosis of sub-segmental acute pulmonary embolism (PE) in an inpatient population explored by 16 slice multi-detector spiral computed tomography (MDCT). Four hundred consecutive inpatients were referred for MDCT for the clinical suspicion of acute PE. One hundred and seventy seven (44.2%) had a known cardio-respiratory disease at the time of examination. Inter-observer and intra-observer agreements for the diagnosis of acute PE and of sub-segmental acute PE were assessed blind and independently by three experienced readers and by kappa statistics. Seventy-five patients were diagnosed as having acute PE findings (19.5%), and clots were located exclusively within sub-segmental arteries in nine patients (12%). When clots were limited to sub-segmental or more distal branches of the pulmonary arteries, kappa values were found to be moderate (0.56) to very good (0.85) for the diagnosis of sub-segmental acute PE, whereas for the diagnosis of acute PE in the whole population, kappa values ranged from 0.84 to 0.97. Intra-observer agreement was found to be perfect (kappa=1). MDCT is a reproducible technique for the diagnosis of sub-segmental acute PE as well as for acute PE. In this inpatient population, sub-segmental acute PE was not a rare event.

Disturbed right ventricular ejection pattern as a new Doppler echocardiographic sign of acute pulmonary embolism

Transthoracic echocardiography (TTE) is frequently performed in patients with suspected acute pulmonary embolism (APE) to search for right ventricular (RV) pressure overload. We prospectively assessed the diagnostic value of a new Doppler echocardiographic sign of APE based on the disturbed RV ejection pattern (“60/60 sign”) and compared its diagnostic performances with that of the presence of RV pressure overload, as well as with “McConnell sign” based on RV regional wall motion abnormalities. We assessed 100 consecutive patients with clinical suspicion of APE, including those with previous cardiorespiratory diseases. After TTE, all of the patients underwent reference diagnostic tests for APE. The 60/60 sign required RV acceleration time of ≤60 ms in presence of tricuspid insufficiency pressure gradient ≤60 mm Hg. APE was ultimately confirmed in 67 of 100 patients. In 17 of 67 patients, 60/60 sign correctly suggested APE, whereas 2 false-positive results were noted: in pulmonary fibrosis and in acute respiratory distress syndrome following lung resection. McConnell sign was fully specific but was noted in only 13 of 67 patients. Sensitivity and specificity were 81% and 45% for “RV-pressure overload” signs, 25% and 94% for 60/60 sign, and 19% and 100% for McConnell sign. When combined, the 2 latter signs were 94% specific and 36% sensitive in diagnosing APE. Thus, RV overload at echocardiography is not specific for APE. The 60/60 and McConnell signs are insensitive, but are reliable and helpful in bedside diagnosis of APE when direct visualization of the pulmonary arteries is impossible. Combining these 2 signs may increase the sensitivity without compromising the specificity of echocardiographic diagnosis of APE.

Pulmonary embolism: a follow-up study of the relation between the degree of right ventricle overload and the extent of perfusion defects.

To describe the course of changes in perfusion lung scintigraphy (LS) after acute pulmonary embolism (PE) and test the hypothesis that patients with persistent pulmonary hypertension (PH)/right ventricle (RV) dysfunction after acute PE can be differentiated from those without through larger perfusion defects (PDf) on LS. Design. Prospective, one-year follow-up study with repeated LS and echocardiography-Doppler investigations. Single centre, University Hospital. Patients with clinical suspicion of acute PE with a diagnosis confirmed by LS and/or pulmonary angiography and able to undergo repeated investigations. Of the 78 patients included, a six-week follow-up was completed in 67 and a one-year follow-up in 64. Time course of PDf in relation to time course of pulmonary artery systolic pressure (PAsP) and RV function. Initially, PDf decreased exponentially, until the beginning of a stable phase, which was achieved within 54 days for 90% of the patients and within 148 days for all. The temporal relation for the regress of PDf and decrease in PAsP was loose. Patients with persistent PDf suffered PH/RV dysfunction more often than those without. However, the variability in the degree of haemodynamic changes for a given extent of PDf was large. After acute PE, LS is of use for the identification of the group of patients that may have persistent PH/RV dysfunction. However. since the identification of individual patients is uncertain, LS cannot replace echocardiography-Doppler in the identification of persistent PH/RV dysfunction after acute PE.