Usefulness of cardiac biomarkers in the prediction of right ventricular dysfunction before echocardiography in acute pulmonary embolism

The prognostic significance of pro-BNP and heart failure in acute pulmonary embolism: A systematic review

Pulmonary embolism (PE) is the third most common type of cardiovascular disease and carries a high mortality rate of 30% if left untreated. Although it is commonly known that individuals who suffer heart failure (HF) are more likely to experience a pulmonary embolism, little is known concerning the prognostic relationship between acute PE and HF. This study aims to evaluate the prognostic usefulness of heart failure and pro-BNP in pulmonary embolism cases. A scientific literature search, including PubMed, Medline, and Cochrane reviews, was used to assess and evaluate the most pertinent research that has been published. The findings showed that increased N-terminal brain natriuretic peptide (NT-proBNP) levels could potentially identify pulmonary embolism patients with worse immediate prognoses and were highly predictive of all-cause death. Important prognostic information can be obtained from NT-proBNP and Heart-type Fatty Acid Binding Proteins (H-FABP) when examining individuals with PE. The heart, distal tubular cells of the renal system, and skeletal muscle are where H-FABP is primarily found, with myocardial cells having the highest concentration. Recent studies have indicated that these biomarkers may also help assess the severity of PE and its long-term risk.

Risk factors for hospital outcomes in pulmonary embolism: A retrospective cohort study

Background

Pulmonary embolism (PE) is not only a life-threatening disease but also a public health issue with significant economic burden. The aim of the study was to identify factors-including the role of primary care-that predict length of hospital stay (LOHS), mortality and re-hospitalization within 6 months of patients admitted for PE.

Method

A retrospective cohort study was conducted with patients presenting to a Swiss public hospital with PE diagnosed at the hospital between November 2018 and October 2020. Multivariable logistic and zero-truncated negative binomial regression analyses were performed to assess risk factors for mortality, re-hospitalization and LOHS. Primary care variables encompassed whether patients were sent by their general practitioner (GP) to the emergency department and whether a GP follow-up assessment after discharge was recommended. Further analyzed variables were pulmonary embolism severity index (PESI) score, laboratory values, comorbidities, and medical history.

Results

A total of 248 patients were analyzed (median 73 years and 51.6% females). On average patients were hospitalized for 5 days (IQR 3-8). Altogether, 5.6% of these patients died in hospital, and 1.6% died within 30 days (all-cause mortality), 21.8% were re-hospitalized within 6 months. In addition to high PESI scores, we detected that, patients with an elevated serum troponin, as well as with diabetes had a significantly longer hospital stay. Significant risk factors for mortality were elevated NT-proBNP and PESI scores. Further, high PESI score and LOHS were associated with re-hospitalization within 6 months. PE patients who were sent to the emergency department by their GPs did not show improved outcomes. Follow-up with GPs did not have a significant effect on re-hospitalization.

Conclusion

Defining the factors that are associated with LOHS in patients with PE has clinical implications and may help clinicians to allocate adequate resources in the management of these patients. Serum troponin and diabetes in addition to PESI score might be of prognostic use for LOHS. In this single-center cohort study, PESI score was not only a valid predictive tool for mortality but also for long-term outcomes such as re-hospitalization within 6 months.

Biomarkers and Right Ventricular Dysfunction

Right ventricular failure is common in critically ill patients, as it frequently results from pulmonary embolism or pulmonary hypertension, and can complicate sepsis and the acute respiratory distress syndrome. Right ventricular dysfunction can be challenging to manage and is associated with poor outcomes in this wide array of disease. Laboratory biomarkers are rapid, noninvasive, accurate, and widely available and thus are useful in the diagnosis and management of right ventricular dysfunction in the critically ill patient. This article discusses the pathophysiology of right ventricular failure and reviews the applications of commonly used biomarkers in right ventricular dysfunction in critical care.

Differential impact of syncope on the prognosis of patients with acute pulmonary embolism: a systematic review and meta-analysis

Aims

Controversial reports exist in the literature regarding the prognostic role and therapeutic implications of syncope in patients with acute pulmonary embolism (PE). We conducted a systematic review and meta-analysis to investigate the association between syncope and short-term adverse outcomes, taking into account the presence or absence of haemodynamic compromise at acute PE presentation.

Methods and results

The literature search identified 1664 studies, 29 of which were included for a total of 21 956 patients with PE (n = 3706 with syncope). Syncope was associated with higher prevalence of haemodynamic instability [odds ratio (OR) 3.50; 95% confidence interval (CI) 2.67-4.58], as well as with echocardiographic signs of right ventricular (RV) dysfunction (OR 2.10; CI 1.60-2.77) at presentation. Patients with syncope had a higher risks of all-cause early (either in-hospital or within 30 days) death (OR 1.73; CI 1.22-2.47) and PE-related 30-day adverse outcomes (OR 2.00; CI 1.11-3.60). The absolute risk difference (95% CI) for all-cause death was +6% (+1% to +10%) in studies including unselected patients, but it was -1% (-2% to +1%) in studies restricted to normotensive patients. We observed no prognostic impact of syncope in studies with a lower score at formal quality assessment and in those conducted retrospectively.

Conclusion

Syncope as a manifestation of acute PE was associated with a higher prevalence of haemodynamic instability and RV dysfunction at presentation, and an elevated risk for early PE-related adverse outcomes. The association with an increased risk of early death appeared more prominent in studies including unselected patients, when compared with those focusing on normotensive patients only.

D-dimer/troponin ratio in the differential diagnosis of acute pulmonary embolism from non-ST elevation myocardial infarction

BACKGROUND/AIMS

The aim of this study was to investigate useful cardiac biomarkers in the differential diagnosis of acute pulmonary embolism (APE) with troponin elevation from acute non-ST elevation myocardial infarction (NSTEMI).

METHODS

A total of 771 consecutive NSTEMI patients with D-dimer measurements and 90 patients with troponin-I (TnI) elevation out of 233 APE patients were enrolled, and cardiac biomarkers were compared.

RESULTS

D-dimer elevation was noted in 382 patients with NSTEMI (49.5%), and TnI elevation was noted 90 out of 233 APE patients (38.6%). Unnecessary coronary angiography was performed in 10 patients (11.1%) among 90 APE patients with TnI elevation. D-dimer was significantly elevated in APE than in NSTEMI (9.9 ± 11.6 mg/L vs. 1.8 ± 4.3 mg/L, p < 0.001), whereas TnI was significantly elevated in NSTEMI (22.4 ± 41.5 ng/mL vs. 0.7 ± 1.4 ng/mL, p < 0.001). D-dimer/TnI ratio was significantly higher in APE than in NSTEMI (50.6 ± 85.3 vs. 1.6 ± 5.7, p < 0.001). On receiver operation characteristic curve analysis, the optimal cut-off value for differentiating APE from NSTEMI was 1.12 mg/L for D-dimer (sensitivity 81.1%, specificity 70.2%), 0.72 ng/mL for TnI (sensitivity 80.6%, specificity 78.9%), and 1.82 for D-dimer/TnI ratio (sensitivity 93.3%, specificity 86.6%).

CONCLUSION

D-dimer/TnI ratio would be a simple and useful parameter for differentiating APE with cardiac troponin elevation from NSTEMI. Optimal cardiovascular imaging to identify APE should be considered in patients with D-dimer/ TnI ratio > 1.82 before performing coronary angiography to avoid unnecessary invasive procedure.

Implications of elevated cardiac troponin in patients presenting with acute pulmonary embolism: an observational study

Background

To evaluate the implications of elevated cardiac troponin (cTn) in patients presenting with pulmonary embolism (PE).

Methods

We conducted a retrospective analysis for patients with PE between 2011 and 2015 with an average of 3 years follow-up. Patients were categorized into two groups based on the cTn status on admission (negative vs. positive) and RV/LV ratio (≤1.2 vs. >1.2). PE diagnosis was made by computed tomography pulmonary angiography (CTPA) examinations.

Results

Among 220 patients with PE, 52.7% had positive cTn and 31.7% had RV dysfunction. Protein S and C deficiency were significantly higher in patients with negative cTn. Patients with positive cTn were more likely to have high-risk simplified pulmonary embolism severity index (sPESI), RV dilation, RV/LV ratio >1.2, severe inferior vena cava reflux and high Qanadli score (QS >18 points). Thrombolytic therapy was used in 15 patients; 9 (60%) of them had elevated troponin. Combined cTn and sPESI had higher sensitivity, negative predictive value and negative likelihood ratio to predict in-hospital mortality. Overall 30-day and 3 years morality were 10.0% and 22.3%; that were significantly higher in patients with positive troponin. Cox regression analysis showed that mortality increased 2.5 times with positive cTn after adjusting for age, sex, and RV dysfunction (adjusted HR 2.5; 95% CI: 1.25-5.01), P=0.009.

Conclusions

Elevated cTn is independent predictor of short and long-term mortality. The predictive power of cTn increases when combined with the clinical probability score. Further, larger prospective studies are needed to confirm the findings of the present study.

Pressure overload induced right ventricular remodeling is not attenuated by the anti-fibrotic agent pirfenidone

Cardiac fibrosis contributes to the development of heart failure in pulmonary hypertension. We aimed to assess the development of fibrosis and the effects of treatment with the anti-fibrotic agent pirfenidone in pressure overload induced right ventricular (RV) failure. Wistar rat weanlings were randomized to pulmonary trunk banding (PTB) or sham surgery. One week after the procedure, PTB rats were randomized into two groups with either six weeks on standard chow or treatment with pirfenidone mixed in chow (700 mg/kg/day). RV hemodynamic effects were evaluated by echocardiography, cardiac magnetic resonance imaging (MRI), and pressure-volume measurements. Sections from the isolated RV, left ventricle, and septum were sampled systematically; stereological point grids and the nucleator were used to estimate volume of fibrosis and cardiac hypertrophy, respectively. PTB caused RV failure in all rats subjected to the procedure. The volume fraction of fibrosis in the RV increased threefold in PTB rats corresponding to a sixfold increase in total volume of RV fibrosis. Volume fraction of fibrosis and total volume of fibrosis also increased in the septum and in the left ventricle. Pirfenidone reduced body weight but did not improve RV hemodynamics or reduce cardiac fibrosis. RV cardiomyocyte profile area was increased twofold in PTB rats without any effect of pirfenidone. RV pressure overload after PTB induced not only RV but also septal and left ventricular fibrosis assessed by stereology. Treatment with pirfenidone reduced body weight but did not reduce the development of cardiac fibrosis or delay the progression of RV failure.

Hospital and intensive care unit management of decompensated pulmonary hypertension and right ventricular failure

Pulmonary hypertension and concomitant right ventricular failure present a diagnostic and therapeutic challenge in the intensive care unit and have been associated with a high mortality. Significant co-morbidities and hemodynamic instability are often present, and routine critical care unit resuscitation may worsen hemodynamics and limit the chances of survival in patients with an already underlying poor prognosis. Right ventricular failure results from structural or functional processes that limit the right ventricle’s ability to maintain adequate cardiac output. It is commonly seen as the result of left heart failure, acute pulmonary embolism, progression or decompensation of pulmonary hypertension, sepsis, acute lung injury, or in the perioperative setting. Prompt recognition of the underlying cause and institution of treatment with a thorough understanding of the elements necessary to optimize preload, cardiac contractility, enhance systemic arterial perfusion, and reduce right ventricular afterload are of paramount importance. Moreover, the emergence of previously uncommon entities in patients with pulmonary hypertension (pregnancy, sepsis, liver disease, etc.) and the availability of modern devices to provide support pose additional challenges that must be addressed with an in-depth knowledge of this disease.

Rapid on-site evaluation of routine biochemical parameters to predict right ventricular dysfunction in and the prognosis of patients with acute pulmonary embolism upon admission to the emergency room

INTRODUCTION

Patients with acute pulmonary embolism(APE)who present with right ventricular dysfunction (RVD) have a worse prognosis. This study aimed to evaluate the value of routine biochemical parameters in predicting RVD and 30-day mortality in patients with APE.

METHODS

We retrospectively collected the clinical data for 154 enrolled patients, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), D-dimer, cardiac troponin I (cTnI), and N-terminal pro-brain natriuretic peptide (NT-proBNP). We analyzed the correlation between RVD and the parameters and conducted a receiver operating characteristic (ROC) curve to confirm the cut-off values for predicting RVD and 30-day mortality. Formulas were built with relevant parameters to predict RVD and 30-day mortality.

RESULTS

Age, NLR, PLR, D-dimer, the ratio of cTnI (+), and NT-proBNP (+) were significantly higher in RVD (+) patients. The ratio of cTnI (+) and NT-proBNP (+) in 30-day mortality (+) patients was significantly higher than that in 30-day mortality (-) patients. According to the logistic regression analysis, NLR, cTnI (+), and NT-proBNP (+) correlated with RVD. The formula for the RVD risk score is 0.072 × NLR+1.460 × NT-proBNP (+)+2.113 × cTnI (+), and the area under the curve (AUC) = 0.890 (95% CI: 0.839-0.941, P = .001). The formula for the 30-day mortality risk score is 0.115 × NLR + 2.046 × NT-proBNP (+) + 1.946 × cTnI (+) -0.016 × PLR, and the AUC = 0.903 (95% CI: 0.829-0.976, P = .001).

CONCLUSIONS

The rapid on-site evaluation of routine biochemical parameters, including NLR, cTnI, and NT-proBNP levels, and the formula developed using these parameters are valuable for predicting RVD and 30-day mortality in patients with APE.

High-sensitivity troponin and right ventricular function in acute pulmonary embolism

INTRODUCTION

Right ventricular (RV) dysfunction has proved to be an important predictor of morbidity and mortality in patients with pulmonary embolism (PE). Tricuspid annular plane systolic excursion (TAPSE) is one of the parameters that have been validated as predictor of outcomes. The aim of our study was to evaluate the performance (sensitivity and specificity) of high-sensitivity cardiac troponin T (hs-cTnT) to predict RV dysfunction defined as TAPSE <16 mm.

METHODS

We conducted a single-center retrospective analysis of 40 patients prospectively included. Median age was 66 years (59-76) and PESI score was 81 (67-100).

RESULTS

Right ventricular dysfunction was present in 30% of the patients and was associated with higher median troponin values (33.5 ng/L vs 16 ng/L; P= .03). A logarithmic relation was observed between hs-cTnT and lower TAPSE values (r(2)= 0.36; P< .0001). The area under the ROC curve of hs-cTnT to predict RV dysfunction was 0.77 (0.63-0.92).

CONCLUSION

hs-cTnT is a biomarker with good performance to identify RV dysfunction in PE.

Plasma Levels of High Sensitivity Cardiac Troponin T in Adults with Repaired Tetralogy of Fallot

Detectable low circulating level of cardiac troponin T (cTnT) may reflect subclinical myocardial injury. We tested the hypothesis that circulating levels of hs-cTnT are altered in adults with repaired tetralogy of Fallot (TOF) and associated with ventricular volume load and function. Eighty-eight TOF patients and 48 controls were studied. Plasma hs-cTnT levels were determined using a highly sensitive assay (hs-cTnT). The right (RV) and left ventricular (LV) volumes and ejection fraction (EF) were measured using 3D echocardiography and, in 52 patients, cardiac magnetic resonance (CMR). The median (interquartile range) for male and female patients were 4.87 (3.83-6.62) ng/L and 3.11 (1.00-3.87) ng/L, respectively. Thirty percent of female but none of the male patients had increased hs-cTnT levels. Female patients with elevated hs-cTnT levels, compared to those without, had greater RV end-diastolic and end-systolic volumes and LV systolic dyssynchrony index (all p < 0.05). For patient cohort only, hs-cTnT levels correlated positively with CMR-derived RV end-diastolic volume and negatively with echocardiography-derived LV and RV EF (all p < 0.05). Multiple linear regression identified sex and RV EF as significant correlates of log-transformed hs-cTnT levels. Increased hs-cTnT levels occur in 30% of female patients after TOF repair, and are associated with greater RV volumes and worse RV EF.

Postoperative Acute Pulmonary Embolism Following Pulmonary Resections

Postoperative acute pulmonary embolism after pulmonary resections is highly fatal complication. Many literatures have documented cancer to be the highest risk factor for acute pulmonary embolism after pulmonary resections. Early diagnosis of acute pulmonary embolism is highly recommended and computed tomographic pulmonary angiography is the gold standard in diagnosis of acute pulmonary embolism. Anticoagulants and thrombolytic therapy have shown a great success in treatment of acute pulmonary embolism. Surgical therapies (embolectomy and inferior vena cava filter replacement) proved to be lifesaving but many literatures favored medical therapy as the first choice. Prophylaxis pre and post operation is highly recommended, because there were statistical significant results in different studies which supported the use of prophylaxis in prevention of acute pulmonary embolism. Having reviewed satisfactory number of literatures, it is suggested that thoroughly preoperative assessment of patient conditions, determining their risk factors complicating to pulmonary embolism and the use of appropriate prophylaxis measures are the key options to the successful minimization or eradication of acute pulmonary embolism after lung resections.

Predictive value of biomarkers for the prognosis of acute pulmonary embolism in Japanese patients: Results of the Tokyo CCU Network registry

BACKGROUND

Several studies from Western countries have reported associations between cardiac troponin and B-type natriuretic peptide (BNP) levels and acute pulmonary embolism prognosis; however, the number of such reports from Asian countries, including Japan, is limited. Thus, we evaluated the relationship between blood biochemical findings and acute-phase pulmonary embolism prognosis in Japanese patients.

METHODS

The subjects included 441 patients with acute pulmonary embolism (191 men, 250 women; average age, 65.8±16.0 years) treated at Tokyo CCU Network Institutions from 2009 to 2011 and registered via survey forms. The association between blood biochemical findings at admission and 30-day mortality was investigated.

RESULTS

The median BNP value was 186.5pg/mL (25th to 75th interquartile range: 49.8-500pg/mL) of 210 cases. No deaths were recorded among those with BNP levels <90pg/mL (n=70), whereas significantly higher mortality (10 deaths/140 cases, 7.1%; p=0.033) was observed among those with BNP levels ≥90pg/mL. A qualitative cardiac troponin test was positive in 58 of the 204 cases (28.4%), with a significantly higher mortality incidence (p=0.017) among the troponin-positive cases [6 (10.3%) versus 3 (2.1%) deaths among the 146 troponin-negative cases]. The overall mean blood glucose level at admission of 331 cases was 152.0±74.0mg/dL, and 30-day mortality significantly increased with blood glucose values (p=0.048).

CONCLUSIONS

Troponin, BNP, and blood glucose levels are useful prognostic biomarkers for acute pulmonary embolism in Japanese patients.

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.

Relationship between N-terminal pro-brain natriuretic peptide, obesity and the risk of heart failure in middle-aged German adults

Background

Both high concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) and obesity are related to higher heart failure risk. However, inverse relationships between NT-proBNP and obesity have been reported. Therefore, it was investigated whether the association between NT-proBNP and the risk of heart failure differed according to obesity status.

Methods

A case-cohort study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam, comprising a random sub-cohort (non-cases = 1,150, cases = 13, mean age: 50.5±9.0 years) and heart failure cases outside the sub-cohort (n = 197). Weighted Cox proportional hazards regression was used to examine the association between NT-proBNP and heart failure risk during a mean follow-up time of 8 years. Stratified analyses were performed according to obesity status as defined by body mass index (<30 kg/m² versus ≥30 kg/m²).

Results

Overall, NT-proBNP was associated with higher risk of heart failure after multivariable adjustment (hazard ratio (HR) and 95% confidence interval (CI): 2.56 (1.49–4.41) for the top versus bottom tertile of NT-proBNP, p_trend:<0.01). In stratified analyses, the shape of association was linear in non-obese and U-shaped in obese participants: HRs (95%CI) from the first to the third tertile of NT-proBNP for non-obese: reference, 1.72 (0.85–3.49), 2.72 (1.42–5.22), and for obese: 3.29 (1.04–10.40), reference, 3.74 (1.52–9.21).

Conclusions

Although high circulating concentrations of NT-proBNP were positively associated with incident heart failure in the entire sample, the association differed according to obesity status. In obese, an increased risk of heart failure was also observed in those with low NT-proBNP concentrations. If confirmed, this observation warrants further investigation to understand underlying pathophysiological mechanisms.

Biohumoral markers as predictor of right ventricular dysfunction in AL Amyloidosis

AIM

In AL amyloidosis, the importance of right ventricle (RV) involvement has recently been underlined and its role in predicting prognosis has been emphasized. Little is known about the relationship between RV involvement, N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin levels. Aim of our study was to clarify the relationship between NT-proBNP and troponin and RV involvement and analyze their independent value as predictors of RV dysfunction.

METHODS AND RESULTS

We examined 76 consecutive patients with biopsy-proven AL amyloidosis. Each patient received complete clinical evaluation, troponin I, NT-proBNP assay and comprehensive echocardiographic evaluation. Considering a tricuspidal annulus plane systolic excursion (TAPSE) value <16 mm, 23 patients (30%) presented RV systolic dysfunction, whereas 53 (70%) did not. Patient with reduced TAPSE had thicker left ventricle (LV) walls and RV free walls, reduced LV fractional shortening, impaired LV diastolic function and worse LV and RV myocardial performance index. For RV dysfunction the best predictive value for NT-proBNP was identified as 2977 ng/l with sensitivity and specificity of 87% and 84%, respectively; best cut-off for troponin I was identified as 0.085 ng/l, with sensitivity and specificity of 85% and 90% respectively. At multivariable logistic regression analysis, both NT-proBNP and troponin I emerged as independent predictors of RV dysfunction presence but troponin appears to have a higher predictive power.

CONCLUSION

Our study demonstrated that cut-off values of 2977 ng/ml for NT-proBNP and 0.085 ng/l for troponin were able to identify a subgroup of AL patients with RV dysfunction. Troponin I is more accurate and seems to be the best biohumoral marker of RV dysfunction.

Current status of the use of inferior vena cava filters in cases of pulmonary embolism in CCUs: From the Tokyo CCU Network

OBJECTIVE

To elucidate the current status of use of inferior vena cava filters (IVCFs) in cases of pulmonary embolism at institutions belonging to the Tokyo CCU Network.

METHODS

We conducted a retrospective investigation of 832 consecutive cases of pulmonary embolism reported on survey forms to the Tokyo CCU Network between 2005 and 2010.

RESULTS

Of 832 cases of pulmonary embolism, IVCFs were used in 338 (40.6%) and not used in 415 (49.9%). Their use was unclear in 79 (9.5%) cases. The use rate gradually increased each year from 2005 until 2008 but decreased from 2009 onward. Moreover, 68.9% of the IVCFs used in cases were non-permanent types. In terms of pulmonary embolism severity, the rate of use was 37.2% in non-massive cases, 49.4% in sub-massive cases, 46.9% in massive cases, and 31.9% in collapse cases. Thirty-day mortality in cases of collapse in which IVCFs were not used was extremely high at 75.8%, suggesting that in many cases, rapid deterioration may occur with insufficient time for IVCF insertion. The differences in IVCF usage rate among institutions were large in the range of 12.5-90% from 2005 to 2008, which slightly declined to the range of 25.0-72.2% from 2009 to 2010.

CONCLUSIONS

We elucidated the current IVCF use status in cases of pulmonary embolism at institutions belonging to the Tokyo CCU Network. Since the status of use differed among institutions, future studies of effective methods of use are required.

Evaluation factors of pulmonary embolism severity and prognosis

Management of pulmonary embolism (PE) is still unclear. We summarized 16 kinds of evaluation factors of PE severity and prognosis, and we analyzed the single and joint value for short-term and long-term prognosis. Among them, biomarkers such as brain natriuretic peptide or N-terminal probrain natriuretic peptide, troponin, and heart-type fatty acid-binding protein are the best indicators of PE severity and short-term prognosis. They might replace imaging detections in evaluating PE severity. But the positive predictive value of all the biomarkers is low, and we need to improve each value through joint detection. The PE severity index and simplified PE severity index are more suitable for evaluating the overall risk and long-term prognosis. They could be used as complements of indicators of the PE severity, especially in identifying low-risk group. Integrated risk stratification and strategies of management should be established based on the 2 aspects mentioned previously.