Pulmonary Thromboembolism Group Research Articles

Quantification of lung perfusion blood volume with dual-energy CT: assessment of the severity of acute pulmonary thromboembolism.

The purpose of this study was to evaluate the usefulness of quantification of lung perfused blood volume (PBV) with dual-energy CT (DECT) for assessment of the severity of acute pulmonary thromboembolism (PTE). We retrospectively analyzed the records of 72 patients with PTE and 168 without PTE who underwent DECT. The PTE patients were divided into high-, intermediate-, and low-risk groups based on clinical symptoms and right ventricular dysfunction. Correlations between quantification of whole-lung PBV and clinical severity were evaluated. Also evaluated was the relation between quantification of whole-lung PBV and right-to-left ventricular diameter ratio on CT images, which was used as an indicator of right ventricular dysfunction. In the PTE and control groups, the whole-lung PBVs were 27.6 ± 7.9 and 29.9 ± 6.8 HU with a significant difference between them (p < 0.0281). In the high-, intermediate-, and low-risk PTE groups, the whole-lung PBVs were 16.0 ± 2.9, 21.0 ± 4.2, and 31.4 ± 5.8 HU with a significant difference between them (p < 0.05). There was no significant difference in whole-lung PBV between the control group and the low-risk PTE group, but there was a significant difference between the control group and the other two PTE groups. In PTE patients, whole-lung PBV had negative correlation with right-to-left ventricular diameter ratio (R = -0.567, p < 0.001). Quantification of lung PBV with DECT is useful for assessment of the clinical severity of PTE and can be used as an indicator of right ventricular dysfunction.

Clinical characteristic and outcomes of lung cancer patients with venous thromboembolism

To explore the clinical characteristics and outcomes of lung cancer patients with venous thromboembolism (VTE). The clinical data of 80 lung cancer patients with VTE hospitalized from January 2003 to April 2013 at our hospital were reviewed. The clinical factors of age, gender, clinical manifestations, pathological type, clinical stage, performance status and therapeutic regimen were recorded and analyzed. And the pulmonary thromboembolism (PTE) patients with deep venous thrombosis (DVT) were enrolled into PTE group. The occurrences, clinical manifestations and prognosis of VTE were evaluated. A total of 80 patients were enrolled. There were 40 males and 40 females with a mean age of (65.8 ± 11.3) years. Adenocarcimoma was identified in 58 (72.5%) patients and advanced lung cancer in 71 (88.8%) patients. Among 37 (46.3%) patients with histodifferentiation results, 89.2% (33/37) of them were moderately and/or poorly differentiated. In 32 (40.0%) patients on chemotherapy, 71.9% (23/32) of them received a platinum-based regimen. There were 35 (43.8%) pulmonary thromboembolism embolism (PTE) and 45 (56.2%) DVT patients. Among PTE patents, 14 (40.0%) were identified incidentally. Dyspnea and swollen of limb were the most common symptoms. Only 20.0% (16/80) patients received VTE prophylaxis. After a definite diagnosis of cancer, 73.8%, 77.5%, 82.5% and 85.0% of patients experienced an event within 3, 6, 9 and 12 months respectively. Up to April 2014, among 53 deceased patients, 77.4% (41/53) died from lung cancer, 9.3% (5/53) PTE while 13.2% (7/53) due to other causes. The cumulative mortality rates within 3, 6, 9 and 12 months after VTE event were 49.1%, 67.9%, 77.4% and 79.2% respectively. Adenocarcimoma, advanced lung cancer, poor histodifferentiation and platinum-based chemotherapy regimen are the risk factors of VTE in lung cancer patients. Most events of VTE occur within 3-6 months after a diagnosis of lung cancer while most mortality cases within 1 year after VTE events.

Evaluation of serum endothelial cell specific molecule-1 (endocan) levels as a biomarker in patients with pulmonary thromboembolism

The aim of this study was to investigate the relationship between pulmonary thromboembolism (PTE) and serum endocan levels. The study included 46 patients with a diagnosis of PTE and control group (25 healthy individuals). Serum endocan levels in all participants' blood samples were measured. The average age of the individuals was 61.76 ± 16.39 years. There was a significant difference in the serum endocan levels between the patients and those of the control group [321.93 ng/l (111.35-2511.33) and 192.77 ng/l (118.30-309.02), respectively; P < 0.030]. The serum endocan levels in the submassive [469.41 ng/l (258.13-800.54)] and the massive PTE groups [719.18 ng/l (319.84-2511.33)] were statistically higher than those in the control group [192.77 ng/l (118.30-309.02)] (P < 0.001 and P < 0.001, respectively). In addition, there was a statistically significant difference between the serum endocan levels of the nonmassive PTE group [188.57 ng/l (111.35-685.56)] and the submassive PTE group (P < 0.01). The serum endocan levels correlated with the international normalization ratio (INR), right ventricular dilatation (RVD) and SBP (r = 0.418, P = 0.004; r = 0.659, P < 0.001; r = -0.425, P = 0.003, respectively). In conclusion, serum endocan levels can be considered a practicable biomarker to determine the severity of PTEs and follow-up thrombolytic therapy.

Clinical features in 23 lung cancer patients complicated with pulmonary thromboembolism

背景与目的已有研究结果表明肺栓塞是恶性肿瘤的常见并发症，并以肺癌多见，本研究探讨肺癌并发肺栓塞患者的临床特点、危险因素及对生存期的影响。方法回顾性分析2009年6月-2013年7月在天津医科大学总医院肿瘤内科就诊明确为肺癌并确诊为合并肺栓塞的23例患者的临床资料，对照组为随机选取同期在总医院肿瘤内科确诊为肺癌患者46例，采用Kaplan-Meier分析总生存时间。结果共确诊肺癌1, 128例，其中23例明确诊断肺栓塞，肺癌合并肺栓塞患者腺癌16例（69.6%），不明原因呼吸困难16例（69.6%），较肺癌组高（P < 0.01），肺癌合并肺栓塞组的血红蛋白、白蛋白、血氧分压较肺癌组低（P < 0.05），白细胞、D-Dimer较肺癌组高（P < 0.05），两组血小板、谷丙转氨酶、谷草转氨酶无统计学差异。肺癌合并肺栓塞同时合并下肢深静脉血栓患者10例（43.48%），急性肺栓塞高危患者6例（26.09%）。单因素分析显示，血红蛋白 < 100 g/L、白细胞 > 11×109/L、D-Dimer > 500 ng/mL、血氧分压 < 80 mmHg、白蛋白 < 30 g/L是肺癌发生肺栓塞的危险因素（OR值分别为5.50、11.03、4.83、4.68、9.63）。16例（69.6%）肺栓塞分布于肺癌确诊前后5个月内，肺栓塞发生于确诊肺癌的时间中位数为3.05个月。截止到2013年7月29日，肺癌合并肺栓塞组患者的中位生存时间为7.77个月，明显低于肺癌组患者的19.27个月（P=0.02），肺癌合并肺栓塞患者化疗组生存时间高于非化疗组。结论肺癌合并肺栓塞患者的常见病理类型为腺癌，其临床表现常见不明原因呼吸困难、咳嗽，肺癌确诊后前5个月为肺栓塞高发时期，肺癌患者发生肺栓塞会降低其生存时间。化疗对于肺癌合并肺栓塞患者的生存有益。

Is Serum Cystatin C a Predictor of Acute Pulmonary Thromboembolism in Patients With Normal Renal Function?

Early diagnosis is the key point in the management of acute pulmonary thromboembolism (PTE). There are no reports in the literature comparing the serum cystatin C levels in patients with acute PTE and normal volunteers. Therefore, in this study, we analyzed 50 patients with acute PTE and 45 healthy volunteers with normal renal function. The serum cystatin C level was significantly higher in the PTE group than in the non-PTE group (1.08 mg/dL [interquantile range (IQR) 0.79-1.56] and 0.85 mg/dL [IQR 0.77-1.03], respectively, P = .017). When determining the presence of PTE, the highest value of sensitivity and specificity was set at a cutoff value of 1.15 mg/dL with 93.3% specificity, 46.0% sensitivity, 88.5% positive predictive value, and 60.9% negative predictive value. In the multivariate model, cystatin C was significantly associated with the presence of PTE (odds ratio: 12.34, 95% CI 2.64-57.75). In conclusion, cystatin C may be an indicator of acute PTE in patients with normal renal function.

Serum Eicosapentaenoic Acid/Arachidonic Acid Ratio Is Low in Patients with Pulmonary Thromboembolism

Recently n-3 polyunsaturated fatty acids (PUFAs) have been reported to play protective roles against cardiovascular diseases. Pulmonary thromboembolism (PTE) is one of the critical diseases in the circulatory system. However the relationship between n-3 PUFAs and PTE has not been reported. A total of 144 outpatients of the division of cardiology, including 12 of PTE cases, were enrolled in the present study and serum levels of eicosapentaenoic acid (EPA) and arachidonic acid (AA) were analyzed. We found that the EPA/AA ratio of the patients with PTE (the PTE group) was significantly lower than that of the patients without PTE (the non-PTE group) (p=0.007 for log EPA/log AA ratio). Next, the PTE group was divided into two groups by the presence or absence of malignant carcinoma. The PTE without carcinoma group showed significantly lower EPA/AA ratio than that of the non-PTE group (p=0.002 for log EPA/log AA ratio). However, the PTE with carcinoma group did not show the statistical difference in EPA/AA ratio compared with the non-PTE group (p=0.39). These data indicate that PTE may be associated with a low EPA/AA ratio, although the presence of malignant carcinoma should be taken into account.

Plasma viscosity levels in pulmonary thromboembolism

Genetic and acquired thrombophilic risk factors may play role on developing venous thromboembolism (VTE). In many cases of pulmonary thromboembolism (PE) it can not be defined any explicit risk factor. In this study we aimed to identify the role of plasma viscosity level on PE. The investigation was planned prospectively and 33 patients with PE and 36 apparently healthy and nonsmoker volunteers as control group were enrolled in the study. The mean plasma viscosity levels were determined in patients with PE and in healthy volunteers as 1.42±0.30 cP and 1.29±0.22 cP respectively. The mean plasma viscosity levels was found to be different between PE and healthy group (p=0.009). The mean levels of triglyceride, fibrinogen and hematocrit were found different between patients with PE and control group (p<0.05). Variables including sex, age, smoking habits, levels of hematocrit, fibrinogen, total cholesterol and triglyceride were not associated with plasma viscosity values in patients with PE. Plasma viscosity levels were found higher in patients with PE compared with healthy indivudials. But it is needed to further studies to define the interactions between factors effecting blood rheology and development of thrombosis.

Protein C polymorphism and susceptibility to PTE in China

Pulmonary thromboembolism (PTE) is a common clinical problem that is associated with substantial morbidity and mortality. We investigated the role of protein C polymorphism in patients with PTE in order to find out the correlation between its polymorphism and the susceptibility of the Chinese population to develop PTE. We used a case-control study design. Sixty-three consecutive patients with PTE were enrolled as the investigated group and 86 healthy people as the control group. Two novel polymorphisms, C/T at the position of 2405 and A/G at the position of 2418in the protein C gene promoter region were detected through PCR-restriction fragment length polymorphism analysis. The results suggested that the genotype frequencies of the two single-nucleotide polymorphisms (SNPs) when combined together were not significantly different between the case and control group (P > 0.05). However, the allele frequency of the C2405T SNP was significantly different between the case and control group. The frequency of T allele in the PTE group was higher when compared to the control, whereas the frequency of C allele was lower (P < 0.05). These results suggested that there were six different kinds of genotype distribution (TA-TA, TA-CA, TA-CG, CG-CG, CA-CG, CA-CA) and three different kinds of haplotype (TA, CG, CA). Our result showed that the frequency of the TA haplotype was significantly higher in the patients suffering from PTE (P < 0.05). These results suggest that the two polymorphisms present in the control region of the protein C gene are associated with an increased susceptibility to PTE in the Chinese population. The 2405T allele may be a possible risk factor for the development of PTE, whereas the C allele may probably be a protective factor of PTE Moreover, the TA haplotype may also be associated with an increased risk for developing PTE.

The Role of Electrocardiography in Follow up of Pulmonary Thromboembolism

ObjectiveElectrocardiography (ECG) is a simple, valuable and easily applicable test that can be used in supporting the diagnosis and assessing the severity of pulmonary thromboembolism (PTE). In this study, it was aimed to identify the role of ECG scoring in diagnosis and follow up of PTE in comparison with community acquired pneumonia (CAP).MethodsPatients with the diagnosis of PTE and CAP were included in the study prospectively between January 2007 and January 2009. ECG scorings were evaluated by two different cardiologists by the method described by Daniel et al at admission (day 0) and day 3, 10 and one month of treatment. Median values of ECG scorings were compared between days and between groups.ResultsForty‐five patients with PTE, 35 patients with CAP were included in the study. Although no statistically significant difference was identified between the ECG scorings of the two groups in each measurement point, ECG scores decreased more rapidly in PTE group within days. Within the PTE group, day 0 ECG score was identified higher in submassive patients than nonmassive ones (p=0.001).ConclusionsAlthough ECG score did not differentiate PTE from CAP, depending on its rapid decrease in PTE, it can be used in the follow up. For submassive PTE patients that must be diagnosed and treated immediately, ECG scorings can be used to support the diagnosis and to assess the clinical severity.

Pulmonary thromboembolism during adult liver transplantation: incidence, clinical presentation, outcome, risk factors, and diagnostic predictors

Intraoperative pulmonary thromboembolism (PTE) is an often overlooked cause of mortality during adult liver transplantation (LT) with diagnostic challenge. The goals of this study were to investigate the incidence, clinical presentation, and outcome of PTE and to identify risk factors or diagnostic predictors for PTE. Four hundred and ninety-five consecutive, isolated, deceased donor LTs performed in an institution for a 3 yr period (2004-6) were analysed. The standard technique was a piggyback method with veno-venous bypass without prophylactic anti-fibrinolytics. The clinical diagnosis of PTE was made with (i) acute cor pulmonale, and (ii) identification of blood clots in the pulmonary artery or observation of acute right heart pressure overload with or without intracardiac clots with transoesophageal echocardiography. The incidence of PTE was 4.0% (20 cases); cardiac arrest preceded the diagnosis of PTE [75% (15)] and PTE occurred during the neo-hepatic phase [85% (17)], especially within 30 min after graft reperfusion [70% (14)]. Operative and 60 day mortalities of patients with PTE were higher (P<0.001) than those without PTE (30% vs 0.8% and 45% vs 6.5%). Comparison of perioperative data between the PTE group (n=20) and the non-PTE group (n=475) revealed cardiac arrest and flat-line thromboelastography in three channels (natural, amicar, and protamine) at 5 min after graft reperfusion as the most significant risk factors or diagnostic predictors for PTE with an odds ratio of 154.32 [95% confidence interval (CI): 44.82-531.4] and 49.44 (CI: 15.6-156.57), respectively. These findings confirmed clinical significance of PTE during adult LT and suggested the possibility of predicting this devastating complication.

The role of quantitative D-dimer levels in the follow-up and differential diagnosis of pulmonary thromboembolism and community-acquired pneumonia

Aim: To identify the quantitative D-dimer levels in pulmonary thromboembolism (PTE) and hospitalized-community acquired pneumonia (CAP) patients, and to determine the alteration of D-dimer levels with anticoagulant or antibacterial therapy. It is not well known that the quantitative analysis of D-dimer has a role in the differential diagnosis of PTE from other diseases. Materials and methods: Serum D-dimer levels were measured and compared prospectively with a latex-enhanced immunoturbidimetric method at admission, before initiating any antibiotic or anticoagulant therapy and then at days 3, 10, and 30 of treatment in PTE and CAP patients. Results: A total of 80 patients (45 PTE and 35 CAP), with a mean age of 61 ± 16 years, were included in the study. Mean D-dimer levels at admission were significantly higher in the PTE group than in the CAP group (3388 ± 2080 vs. 1190 ± 1089 µ/L, P = 0.001). After initiating the anticoagulant therapy, a significant decrease in D-dimer levels was identified in the PTE group, but not in the CAP group, on day 3 (678 ± 652 µ/L vs. 724 ± 907 µ/L). In the receiver operating characteristic curve analysis, D-dimer levels of >1700 µ/L were statistically significant as a cut-off value for the diagnosis of PTE (AUC: 0.820; 95% CI: 0.73-0.92). Conclusion: Although serum quantitative D-dimer levels cannot be used solely for the differential diagnosis of CAP and PTE, they might be helpful in making the decision to perform further diagnostic methods. Since D-dimer levels decreased more rapidly and significantly in PTE than CAP cases, they might be used as a marker for monitoring the treatment response in patients with PTE, but this must be proven with more comprehensive studies.

Tenascin-C May Be a Predictor of Acute Pulmonary Thromboembolism

Numerous studies have shown an increase in NT-pro BNP, troponin I and D-dimer levels with right ventricular dysfunction on echocardiography in patients with acute pulmonary thromboembolism (PTE). We found no data about the relation between tenascin-C and acute PTE in the litera-ture. The aim of this study was to evaluate tenascin-C levels in acute PTE and correlate them with NT-pro BNP, troponin I and D-dimer. Thirty-four patients who have massive or submassive PTE on spiral thorax CT (PTE group) and twenty healthy volunteers (non-PTE group) were evaluated. In all patients, right ventricular functions were obtained on transthoracic echocardiography and plasma tenascin-C, NT-pro BNP, troponin I, and D-dimer levels were measured. The left ventricular systolic diameter, left ventricular diastolic diameter and left ventricular ejection fraction were similar in the two groups. The right heart chamber sizes and main pulmonary artery diameter were significantly larger in the PTE group and systolic pulmonary artery pressures were also significantly higher in this group. Tenascin-C, NT-pro BNP, and D-dimer levels were also significantly higher in the PTE group than in the non-PTE group (p< 0.001). The troponin I levels did not differ between the two groups (p=0.4). Tenascin-C was found to be highly correlated with sPAP and NT-pro BNP and correlated with D-dimer; however, troponin I was not correlated with tenascin-C. This study demonstrates that tenascin-C may be an indicator of acute PTE.

Cut-off value of D-dimer in pulmonary thromboembolism and pneumonia

Aim: The differential diagnosis of pulmonary thromboembolism (PTE) and pneumonia remains difficult in emergency rooms. High D-dimer levels in the pneumonia may be misdiagnosed as PTE on the basis of similar clinical, radiological, and laboratory findings. Since D-dimer elevation may also be seen in pneumonia cases, the comparison of D-dimer values in patients diagnosed as pneumonia and PTE, in order to determine a cut-off value between the 2 diseases, was aimed in this study. Materials and methods: Patients in the community acquired pneumonia (CAP) group were classified according to the American Thoracic Society (ATS) 2001 criteria. Groups III and IV patients, who were hospitalized, were included in the study. The final CAP group consisted of 52 patients (30 in Group IIIa, 15 in Group IIIb, 2 in Group IVa, and 5 in Group IVb) and 68 patients with a diagnosis of PTE. All patients’ D-dimer levels in the first day were recorded. Results: Mean D-dimer levels of the PTE and pneumonia group were 4868 ng/mL and 2068 ng/mL, respectively (P < 0.001). Cut-off value was 4374 ng/mL. Mean levels of D-dimer in the massive PTE group and sub-massive PTE group were 5438 ng/mL and 4175 ng/mL,respectively, (P = 0.04). Conclusion: Elevation of D-dimer is more significant in PTE than pneumonia. As a result, if D-dimer level is higher than 4374 ng/mL, the patient should be evaluated for the diagnosis of PTE. A cut-off value of 4374 ng/mL will help the discrimination of PTE and pneumonia.

Usefulness of the 12-Lead Electrocardiography in the Diagnosis and Evaluation of Severity of Pulmonary Thromboembolism

Background and Objectives:Aggressive medical management, such as thrombolytic therapy, is necessary to save the lives of patients with acute severe pulmonary thromboembolism (PTE). The ECG changes associated with PTE are usually nonspecific, but severe PTE can produce some specific ECG findings. The purpose of this study was to determine the role of 12-lead ECG in the diagnosis of PTE, as well as the evaluation of its severity in therapeutic decision making. Subjects and Methosds:We analyzed 42 patients (60.5±14.9 years, 17 men), in whom PTE had been confirmed by chest CT angiography or radionuclide ventilation-perfusion scan, and 63 control patients (60.3±16.5 years, 21 men), who had various cardiovascular diseases, with the exception of PTE. The systolic pulmonary artery pressure (sPAP) was estimated by Doppler echocardiography. Results:Among the finding derived from the 12-lead ECG, the sinus tachycardia (35.7 vs. 12.7%, p=0.005), a QRS axis over 90 degree (28.5 vs. 7.9%, p=0.005), the S1Q3T3 sign (45.2 vs. 23.8%, p=0.021) and T-wave inversion at V2-4 (31.0 vs. 14.3%, p=0.040) were more common in the PTE than the control group. There were no significant ECG changes in 3 patients (7.1%) in the PTE group. In the PTE group, the T-wave amplitudes at leads II and aVF showed correlation with the sPAP (r=-0.400, p=0.009; r=-0.321, p=0.038, respectively). A T-wave amplitude greater than 0.5 mm at lead II was predictive of severe pulmonary hypertension (50 mmHg) in patients with PTE, with a sensitivity , specificity, positive predictive value and negative predictive value of 59.3, 86.7, 88.9 and 54.2%, respectively (OR=6.532, 95% CI, 1.592 to 26.785). Conclusion:The use of common ECG abnormalities as diagnostic tools of PTE was limited, due to their low sensitivity, despite the high specificity. However, the T-wave amplitude (cut-off value=0.5 mm) at lead II was very simple and useful in distinguishing patients with severe pulmonary thromboembolism from those without. (Korean Circulation J 2005;35:389-395)

Assessment of Right Ventricular Diastolic Function by Pulsed Doppler Echocardiography in Chronic Pulmonary Disease and Pulmonary Thromboembolism

We evaluated right ventricular (RV) diastolic performance in 12 healthy subjects (control), 25 patients with chronic pulmonary diseases (CPD) and 6 patients with chronic pulmonary thromboembolism (PTE). Flow velocity patterns were determined by the pulsed Doppler technique. The values determined included acceleration time (AT), deceleration time (DT), and the ratio of the atrial contraction wave (A) to the rapid filling wave (R) (A/R ratio) from flow velocity patterns in the RV inflow tract. DT was significantly prolonged in the CPD and PTE groups compared with the control group, indicating dysfunction during the early (middle) filling period. The prolongation was marked in those patients with pulmonary hypertension. The A/R ratio was significantly higher in the CPD and PTE groups than in the control group, indicating a decrease in RV compliance. The A/R ratio increased slightly with the increase in the end-diastolic volume index. These results suggested that the pressure overload plays an important role in RV diastolic dysfunction in patients with pulmonary disease, and that preload contributes to the dysfunction.

Pulmonary thromboembolism

To improve the available techniques, diagnostic and therapeutical policies were analyzed in patients with angiographically documented pulmonary thromboembolism (PTE). The investigation included 151 patients with suspected PTE. Angiopulmonography from the pulmonary trunk and great branches provided data on the pulmonary vessels. The diagnosis of PTE was verified in 138 patients: acute massive and submassive types in 44 patients, mild and chronic PTE in 22 and 72 patients, respectively. Fibrinolytic therapy was performed in 34 patients with acute PTE, the others were treated with heparin. In the massive and submassive PTE group, the Miller index was 23.7 +/- 0.86 scores, pulmonary systolic pressure was 56.2 +/- 2.7 mm Hg. The mortality rates were 29.5%, the Miller residual index was 9.9 +/- 1.1 scores. In the mild PTE group, the Miller index averaged 5.2 +/- 0.88 scores, pulmonary pressure was in the upper normal range. All patients with this type recovered after treatment, the residual index was 1.4 +/- 0.5 scores. Fibrinolysis is the method of choice in the treatment of massive pulmonary embolism: however, the administration of large-dose heparin may be rather effective. Heparin therapy ensures blood flow recovery in mild PTE. The severity of pulmonary circulatory and hemodynamic disorders and the time of therapy initiation determine the efficiency of treatment in acute PTE.