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At least 289 records · Page 16Linked to original sources
PubMed2002

Coronary risk stratification in patients with end-stage lung disease.

BACKGROUND: Significant coronary artery disease (CAD) has been a contraindication for listing patients for lung transplantation. We hypothesize that coronary risk stratification can help identify a sub-set of patients who need additional diagnostic tools and intervention. METHODS: We performed a retrospective review of 72 consecutive patients who underwent lung transplantation at our institution from 1995 to 2000. Further, a review of patients who are currently listed for transplantation yielded 48 patients. We then identified the various risk factors for CAD, the diagnostic tools used, and pre-operative intervention. Risk factors identified included smoking history, diabetes, hypertension, hypercholesterolemia, CAD, congestive heart failure, age >50, and arrhythmias. Based on these risk factors, the patients were then classified into 2 groups: low risk (< or =1 risk factors) and high risk (> or =2 risk factors). We identified the patients in each group who underwent coronary angiography (CA), those with angiographic evidence of CAD, and those who received pre-operative intervention. RESULTS: Of the 72 patients who underwent lung transplantation, 48 were identified as at high risk for CAD. Of these, 5 patients had CAD diagnosed before surgery using CA, and 1 patient received pre-operative intervention. Of the 48 patients currently on the lung transplant list, we identified 28 patients as high risk for CAD, 12 of whom were noted to have CA, and 2 of whom received pre-operative intervention. CONCLUSIONS: Although CAD was once a contraindication for lung transplantation, pre-operative risk stratification allows identification of CAD with CA in a high-risk group. We believe that by using appropriate pre-operative cardiac intervention, patients with severe CAD could successfully undergo lung transplantation.

Adolescent↗
PubMed2003

Vertical stratification of fatty acids in the blubber of southern elephant seals (Mirounga leonina): implications for diet analysis.

Fatty acid signature analysis (FASA) is a powerful ecological tool that uses essential fatty acids (FA) from the tissues of animals to indicate aspects of diet. However, the presence of vertical stratification in FA distribution throughout blubber complicates the application of FASA to marine mammals. Blubber biopsy samples were collected from adult female southern elephant seals (Mirounga leonina) from Macquarie Island (n=11), and blubber cores were divided into inner and outer sections to determine the degree to which the blubber layer was stratified in FA composition, we found 19 FA from both blubber layers in greater than trace amounts (>0.5%). The inner and outer blubber layers could be separated using principal components analysis based on the relative proportion of FA in each layer. Dietary polyunsaturated fatty acids (PUFA) were also observed in significantly higher proportions in the inner blubber layer. Due to the degree of FA stratification in southern elephant seals, we concur with other marine mammal studies that sampling only the outer blubber layer will result in a loss of recently accumulated information regarding diet structure (as indicated by 'surplus' PUFA from the diet). This finding suggests that differential mobilization/deposition of certain FA may result in a modified signature from prey to predator. Thus, sampling animals to recover the inner blubber layer is important for studies attempting to describe aspects of marine mammal diet. This can be achieved in animals such as pinnipeds where the whole blubber layer can be readily sampled.

Adipose Tissue↗
PubMed2004

Wall thickening assessment with tissue harmonic echocardiography results in improved risk stratification for patients with non-ST-segment elevation acute chest pain.

OBJECTIVES: To demonstrate whether the improved imaging quality gained by using tissue harmonic echocardiography in place of fundamental echocardiography results in the improved risk stratification of patients presenting with non-ST-elevation acute chest pain. METHODS AND RESULTS: Eighty patients with over 30 min of non-ST-elevation chest pain that had lasted less than 6 h were recruited. All patients underwent resting tissue harmonic and fundamental echocardiographic scans. Diagnosis for acute myocardial infarction was made on a 24 h creatine kinase-MB sample. Echocardiographic images were reported by two experienced blinded observers. Patients were followed up at least 4 months after admission. Endpoints included all-cause mortality, non-fatal myocardial infarction and revascularisation procedures. Tissue harmonic echocardiography allowed assessment of all myocardial segments in all patients compared to 43/78 patients ( p<0.001 ) with fundamental echocardiography. A wall thickening abnormality demonstrated on tissue harmonic echocardiography and not fundamental echocardiography was a significant predictor of index myocardial infarction on admission ( p<0.007 ) and for an adverse cardiac event during follow up ( p=0.002 ). CONCLUSIONS: Tissue harmonic echocardiography is superior to fundamental echocardiography for accurate assessment of systolic wall thickening and hence risk stratification for patients presenting with acute chest pain and non-diagnostic electrocardiogram changes.

Acute Disease↗
PubMed2003

Risk stratification for adverse outcome in cardiac surgery.

Risk-adjusted outcome prediction is mainly important in two separate fields. The first is quality monitoring: measuring actual versus predicted mortality in an institution allows assessment of the clinical surgical and anaesthesia performance while adjusting for the risk profile of the patients. Without risk stratification, surgeons and hospitals treating high-risk patients will appear to have worse results than others. This may prejudice referral patterns, affect the allocation of resources and even discourage the treatment of high-risk patients. The second field is that of informed consent and clinical decision-making. Risk-adjusted predicted mortality should form an important part of patient and surgeon decisions on whether or not to proceed with surgery. Clearly, no 'perfect' model can be produced as some aspects of mortality will always be related to risk factors not included in the model (e.g. the quality of the distal coronary artery vessels in coronary artery surgery) or due to chance happenings not related to preoperative patient characteristics (such as surgical error). An individual patient will either survive or die after cardiac surgery. Clearly, no scoring system will predict the specific outcome for every patient. However, risk stratification will inform patients and clinicians of the likely risk of death for a group of patients with a similar risk profile undergoing the proposed operation. This information is useful and should form part of the basis on which the patient and surgeon decide whether to proceed.

Cardiac Surgical Procedures↗
PubMedDate not supplied

Stratification of α ganglion cells and ON/OFF directionally selective ganglion cells in the rabbit retina.

The correlation between cholinergic sensitivity and the level of stratification for ganglion cells was examined in the rabbit retina. As examples, we have used ON or OFF alpha ganglion cells and ON/OFF directionally selective (DS) ganglion cells. Nicotine, a cholinergic agonist, depolarized ON/OFF DS ganglion cells and greatly enhanced their firing rates but it had modest excitatory effects on ON or OFF alpha ganglion cells. As previously reported, we conclude that DS ganglion cells are the most sensitive to cholinergic drugs. Confocal imaging showed that ON/OFF DS ganglion cells ramify precisely at the level of the cholinergic amacrine cell dendrites, and co-fasciculate with the cholinergic matrix of starburst amacrine cells. However, neither ON or OFF alpha ganglion cells have more than a chance association with the cholinergic matrix. Z -axis reconstruction showed that OFF alpha ganglion cells stratify just below the cholinergic band in sublamina a while ON alpha ganglion cells stratify just below cholinergic b . The latter is at the same level as the terminals of calbindin bipolar cells. Thus, the calbindin bipolar cell appears to be a prime candidate to provide the bipolar cell input to ON alpha ganglion cells in the rabbit retina. We conclude that the precise level of stratification is correlated with the strength of cholinergic input. Alpha ganglion cells receive a weak cholinergic input and they are narrowly stratified just below the cholinergic bands.

Action Potentials↗
PubMed2004

Pre-randomization decisions and group stratification in a randomized controlled trial to improve prescribing.

OBJECTIVE: To select and evaluate characteristics of primary care practice groups relevant for stratification prior to randomization. METHOD: Structured telephone interviews and pre- and post-intervention prescription data. SETTING: Additional study in an RCT to rationalize prescribing in primary care, addressing groups of pharmacists and doctors. Representatives of 61 primary care practice groups in the Netherlands. MAIN OUTCOME MEASURES: Identification and evaluation of primary care practice group characteristics related to changes in prescribing. These characteristics were evaluated by estimation of incidence rate ratios (Poisson regression). RESULTS: Of practice groups 40 representatives (66%) participated in our study. Three characteristics were found to be most relevant for stratification: the purpose of the practice groups (whether they participated in information exchange (n = 14) or binding consensus on pharmacotherapy (n = 26)), the use of a formulary (22 practice groups did and 18 groups did not) and the use of feedback data (22 groups did and 18 groups did not). These characteristics strongly modified the effect of the program on prescribing behaviour. While the overall effect of the program was to significantly reduce the prescribing of the targeted drugs, this change was not consistent in all strata. CONCLUSION: Assessment of the characteristics of practice groups made it possible to define factors to be used for a stratified randomization of practice groups which in retrospect indeed modified the effect of an educational intervention directed to change prescribing. Such pre-randomization assessments can be a useful tool in interventions designed to improve practice patterns in groups of physicians.

Communication↗
PubMed2002

[Diagnosis and risk stratification of acute coronary syndrome in general practice and in the hospital].

Acute coronary syndromes usually present as acute chest pain but a manifestation with atypical symptoms or entirely without symptoms makes rapid diagnosis of this potentially lethal syndrome difficult and may lead to delay of the appropriate therapy. The role of the practitioner in this situation is complex since early exclusion of an acute coronary syndrome may be very difficult with the means available in a private practice; on the other hand the early hours which are critical for early therapy may be lost in a private practice. In the early phase of an acute coronary syndrome, diagnoses and risk stratification are based primarily on history, clinical presentation, ECG and biological markers. In the hospital, the time course of these parameters, functional tests for diagnosis and risk stratification as well as determination of left ventricular function and coronary angiography have additional relevance. Recent developments are the availability of highly sensitive and specific biological markers (Troponins), the new classification in acute coronary syndrome with and without ST-elevation and the identification of inflammatory processes in the coronary artery, which have added importantly to our understanding of the acute coronary syndrome. The availability of very early therapy and the possibilities of telemedicine have the potential to influence the pre-hospital diagnostic strategy and management of acute coronary syndromes.

Angina, Unstable↗
PubMed2004

Population stratification in the candidate gene study: fatal threat or red herring?

Advances in molecular genetics have provided behavioral scientists with a means of investigating the influence of genetic factors on human behavior. Unfortunately, recent candidate gene studies have produced inconsistent results, and a frequent scapegoat for the lack of replication across studies is the threat of population stratification. This review of the literature on population stratification suggests that the threat may be a red herring. Reliable findings will require improved specification and measurement of the behavioral phenotypes in question, a renewed focus on internal validity, and the specification and testing of genetic factors in the context of longitudinal multivariate models. In this respect, behavioral scientists are well suited to investigating genetic factors that influence psychological mechanisms.

Case-Control Studies↗
PubMed2006

Principal components analysis corrects for stratification in genome-wide association studies.

Population stratification--allele frequency differences between cases and controls due to systematic ancestry differences-can cause spurious associations in disease studies. We describe a method that enables explicit detection and correction of population stratification on a genome-wide scale. Our method uses principal components analysis to explicitly model ancestry differences between cases and controls. The resulting correction is specific to a candidate marker's variation in frequency across ancestral populations, minimizing spurious associations while maximizing power to detect true associations. Our simple, efficient approach can easily be applied to disease studies with hundreds of thousands of markers.

Algorithms↗
PubMed1998

Use of dobutamine echocardiography for cardiac risk stratification of patients with chronic renal failure.

OBJECTIVES: This study sought to define the value of dobutamine echocardiography (DbE) for cardiac risk stratification in patients with chronic renal failure (CRF). DESIGN: Outcome study correlating results of DbE with late cardiac events in patients with CRF. SETTING: Academic medical centre. SUBJECTS: All patients with CRF (serum creatinine > 2.5 mg dL-1) undergoing DbE were studied; we analysed 193 consecutive patients (aged 63 +/- 13 years, 73 men). INTERVENTIONS: A standard dobutamine-atropine stress was administered until attainment of peak dose, or the development of severe ischaemia or side-effects. The electrocardiogram (ECG) and echocardiogram were obtained before, during and after stress. Ischaemia was identified by new or worsening wall-motion abnormalities with stress. OUTCOME MEASURES: Patients were followed up after 38 +/- 14 months for cardiac death, myocardial infarction or coronary disease progression requiring revascularization. RESULTS: DbE demonstrated ischaemia in 36 patients (19%), scar in 36 (19%) and a normal study in 121 patients. The heart-rate response to dobutamine was submaximal (< 85% age-predicted heart rate) in the absence of wall-motion abnormalities in 69 patients (36%), 54 of whom completed the protocol. Follow-up data were complete in 191 patients (99%); cardiac events occurred in 33 patients (17%), including 17 with cardiac death, 7 with infarction, and 9 requiring late revascularization. Spontaneous events occurred in 7 patients with ischaemia, 3 with scar (8%), 11 with a nondiagnostic study (16%) and 3 patients with a normal study (6%). Over the entire follow-up, the event-free survival in patients with ischaemia (66%) was markedly lower than those without ischaemia (84%, P = 0.006). However, the event rate in patients with nonischaemic responses increased from 8% to 16% between 24 and 40 months, and whilst ischaemia was an independent predictor of outcome at 24 months, it was not at 40 months. CONCLUSIONS: In patients with CRF, the identification of ischaemia at DbE is associated with a significant risk of adverse cardiac events. Patients with nonischaemic scans have a low frequency of events over short-term follow-up, but this increases at later follow-up. These later events may reflect progressive coronary disease, attributable to the atherogenic milieu of these patients, and imply that repeated testing may be required to maintain cardiac risk stratification in patients with CRF.

Adrenergic beta-Agonists↗
PubMed2000

Classification of discordant fetal growth may contribute to risk stratification in monochorionic twin pregnancies.

OBJECTIVES: To determine whether classification of discordant growth between fetal twins allows risk stratification in monochorionic twin pregnancies. METHODS: In 12 twin-to-twin transfusion syndrome (TTTS) pregnancies and 12 cases that were suspected of developing the syndrome, fetal growth was determined by serial standard sonography. Fetal growth was expressed as the difference-average-ratio (DAR), defined as the difference in estimated fetal weight between both twins divided by their average weight. In each case, we determined the maximum value of DAR and the rate of change of DAR using a least squares linear fit of the estimated fetal weights. RESULTS: For the TTTS cases the maximum value of DAR was 0.44 +/- 0.21 versus 0.52 +/- 0.13 for the suspected TTTS cases (P = 0.25). The rate of change of DAR was 0.052 +/- 0.034 per week for the TTTS versus 0.0055 +/- 0.0092 for the suspected TTTS cases (P = 0.0004). After laser therapy, DAR decreased in four successful cases, with a rate of change of -0.0146 +/- 0.0093 per week, but increased further in one unsuccessful case, due to patent anastomoses. In the seven TTTS cases treated with amnioreduction, DAR did not decrease; in one of two suspected TTTS cases the DAR decreased slightly. In the nine amnioreduction cases, the average rate of change of DAR was 0.067 +/- 0.083 per week. This was significantly different from the four successful laser cases (P = 0.01). CONCLUSIONS: The rate of change of DAR, but not DAR itself, has prognostic value for the development of suspected TTTS pregnancies, for the onset and severity of TTTS and for the efficacy of therapy. This parameter is derived from routine sonography examination and may contribute to risk stratification in monochorionic twin pregnancies.

Female↗
PubMed2000

Predicting acute renal failure after coronary bypass surgery: cross-validation of two risk-stratification algorithms.

BACKGROUND: Acute renal failure (ARF) requiring dialysis after coronary artery bypass grafting (CABG) occurs in 1 to 5% of patients and is independently associated with postoperative mortality, even after case-mix adjustment. A risk-stratification algorithm that could reliably identify patients at increased risk of ARF could help improve outcomes. METHODS: To assess the validity and generalizability of a previously published preoperative renal risk-stratification algorithm, we analyzed data from the Quality Measurement and Management Initiative (QMMI)1 patient cohort. The QMMI includes all adult patients (N = 9498) who underwent CABG at 1 of 12 academic tertiary care hospitals from August 1993 to October 1995. ARF requiring dialysis was the outcome of interest. Cross-validation of a recursive partitioning algorithm developed from the VA Continuous Improvement in Cardiac Surgery Program (CICSP) was performed on the QMMI. An additive severity score derived from logistic regression was also cross-validated on the QMMI. RESULTS: The CICSP recursive partitioning algorithm discriminated well (ARF vs. no ARF) in QMMI patients, even though the QMMI cohort was more diverse. Rates of ARF were similar among risk subgroups in the CICSP tree, as was the overall ranking of subgroups by risk. Using logistic regression, independent predictors of ARF in the QMMI cohort were similar to those found in the CICSP. The CICSP additive severity score performed well in the QMMI cohort, successfully stratifying patients into low-, medium-, high-, and very high-risk groups. CONCLUSIONS: The CICSP preoperative renal-risk algorithms are valid and generalizable across diverse populations.

Acute Kidney Injury↗
PubMedDate not supplied

Significance of cell cycle for wound stratification in clinical trials: analysis of a pressure ulcer clinical trial utilizing cyclin D/cdk4.

During the past 5 years, progress in the treatment of pressure ulcers appears to have reached a plateau. Several factors in the design of recent clinical studies may have contributed to this situation. These factors include the criteria chosen for patient selection, small sample size, and lack of a concisely defined final clinical outcome. Hunt noted that wound stratification according to a patient's physiological characteristics may be a key to quantifying differences among clinical treatments. To address this issue, we examined the expression of cyclin D/cdk4 in pressure ulcer fibroblasts taken from tissues during a recent clinical trial. The treatment groups included patients treated with the following regimens: placebo, granulocyte macrophage-colony stimulating factor alone, basic fibroblast growth factor alone, or granulocyte macrophage-colony stimulating factor and basic fibroblast growth factor given in sequence. Immunocytochemical colocalization of cyclin D and cdk4 showed that, before the initial treatment began, patients were distributed disproportionately among treatment subgroups in regards to the initial expression of these markers. For example, we found that compared with other subgroups, ulcer fibroblasts in the basic fibroblast growth factor treatment group showed a much lower expression of cyclin D/cdk4 at day 0. However, this group exhibited higher levels of expression of this complex after 35 days of treatment. This study shows that measurement of cyclin D/cdk4 expression permits more accurate stratification of patients within treatment subgroups, measurement of a cell's ability to detect the presence of functional cytokines, identification of area(s) of failure within the G1 of the cell cycle, and a basis for critical evaluation of various treatments.

Cell Cycle↗
PubMed1999

Using an outcomes-based approach to identify candidates for risk stratification after exercise treadmill testing.

OBJECTIVE: To develop a hierarchical approach to cardiac risk stratification after treadmill testing. PATIENTS: Clinical and treadmill test data were used to identify a patient population that may be candidates for further risk stratification with stress tomographic myocardial perfusion imaging. A prospective series of 3, 620 medically treated patients (42% female, mean age 63 years) with a 2.5% mortality was identified (follow-up 2.5 +/- SD 1.5 years). MEASUREMENTS AND MAIN RESULTS: A Cox proportional hazards model was used to estimate a patient's likelihood of cardiac death. Kaplan-Meier survival curves were used to estimate time to cardiac death by nuclear test results. Annual rates of cardiac death were 0. 4% (n = 921), 1% (n = 2,498), and 1% (n = 201) for patients with low, intermediate, and high Duke treadmill scores (DTS). For patients with an intermediate DTS, multivariate estimators of cardiac death included the number of ischemic vascular territories (relative risk per defect 1.4, p =.01), the number of infarcted vascular territories (relative risk per defect 2.4, p =.00001), and the DTS (relative risk per unit 0.97, p =.00001), following adjustment for a patient's pretest risk of coronary disease. For patients with an intermediate DTS, the presence of no, one or two, and three vascular territories with defects was associated with annual rates of cardiac death of 0.5%, 1.4%, and 2.5%, respectively (p <.0001). Kaplan-Meier survival curves exhibited a statistically worsening survival for patients with defects by 1 year after treadmill exercise. CONCLUSIONS: For symptomatic patients with an intermediate treadmill test score, the exercise myocardial perfusion scan may be used to stratify their risk of cardiac death over 3 years of follow-up. Patient management may be efficiently guided by further outcome assessment, with an exercise nuclear scan for patients whose treadmill test score is intermediate.

Aged↗
PubMed2003

Association of the heart rate turbulence with classic risk stratification parameters in postmyocardial infarction patients.

The heart rate turbulence (HRT) parameters were introduced for risk stratification of ventricular arrhythmias in postmyocardial infarction patients. However, the relationship of these parameters with other risk stratificators such as heart rate variability (HRV), repolarization parameters or left ventricular function is unknown. Furthermore, the influence of age and medication on HRT remains to be evaluated. Holter ECG's of 509 post-MI patients (1-10 years after MI) were screened for single ventricular extrasystole. In 196 patients the parameters' turbulence onset (TO) and turbulence slope (TS) could be computed. A pathological TO (>0%) and TS (<2.5 ms) was found in 58 and 54 patients, respectively. HRT was not related to gender, but was correlated with age (TS: r = 0.209, P < 0.01). No relationship was observed between QT interval, QTc interval or QT dispersion and HRT parameters. Individuals with a pathological HRT showed decreased HRV values (e.g., PNN50: 2.8 vs. 11.5; P < 0.001). Of all MI patients with systolic left ventricular dysfunction (EF < 45%, n = 46), 18 showed a pathological TO (39%) compared to 34 out of 142 patients (24%) with an EF > 45%. In contrast, the percentage of pathological HRT was not different between patients with left ventricular hypertrophy (16 out of 59, 27%) compared to patients without LVH (38 out of 133, 28%). The HRT was pathological in 14 out of 24 patients with diabetes mellitus (58%) compared to 40 out of 172 (23%) normoglycemic patients (TO: -0.6 +/- 3.1 vs. -2.5 +/- 5.5, P < 0.02). HRT was similar in patients with ss-blockers (n = 96) as in patients without ss-blockers (n = 100). In stable post-MI patients, HRT is influenced by age and left ventricular function and correlates with heart rate variability. Therapy with ss-blockers has no influence on HRT, while diabetic patients may have an increased likelihood of pathological HRT.

Age Distribution↗
PubMed2002

Do cytokines enable risk stratification to be improved in NYHA functional class III patients? Comparison with other potential predictors of prognosis.

AIMS: Elevated plasma levels of proinflammatory cytokines have been reported in patients with congestive heart failure. The purpose of this study was to assess whether cytokines improve risk stratification in a homogeneous group of NYHA class III patients with a left ventricular ejection fraction <40%. METHODS AND RESULTS: Plasma concentrations of big endothelin, tumour necrosis factor alpha, interleukins -1, -6, -10 and -12, sCD14 and GM-CSF were measured by ELISA in 91 NYHA III patients [mean (SD) age: 55 (10) years, 69% male, 34% coronary artery disease, 66% dilated cardiomyopathy] with a left ventricular ejection fraction and a peak oxygen uptake (peak VO2) of 19 (9)% and 12.1 (3.6) ml x min(-1) x kg(-1), respectively. During follow-up [22 (13) months], 31 patients (34%) died due to cardiovascular causes. In non-survivors, interleukin-6 was twice as high as in survivors [12.8 (16.9) pg x ml(-1)vs 5.6(5.3) pg x ml(-1), P<0.003], whereas plasma concentrations of the other cytokines showed no significant differences. Concerning long-term survival (> or =1 year), multivariate Cox regression analysis revealed an independent prognostic power for interleukin-6, which was further improved by combining with left ventricular ejection fraction and peak VO2, while for short-term survival (up to 6 months) interleukin-6 did not allow risk stratification. CONCLUSION: In NYHA class III patients, plasma concentrations of interleukin-6 are predictive of long-term survival. However, its value may be limited for clinical decision-making for cardiac transplantation (short-term survival).

Aged↗
PubMed2001

Risk stratification for training in cardiac surgery.

BACKGROUND: There is a potential conflict of interest in providing the best possible outcome for patients undergoing cardiac surgery and good training for junior cardiac surgeons. METHODS: We analysed training with reference to volume of work, risk stratification and outcome for consultant and trainee procedures. The Parsonnet system was used for risk stratification. A retrospective audit was performed for a 6-year period. RESULTS: During the study period, 6037 operations were performed, of which 2166 were carried out by trainees. Direct consultant assistance in a trainee operation varied between 17% and 51% and increased towards the end of the study period. Of the operations performed by trainees, 88% were CABG. The median Parsonnet score for consultant operations was 9 compared with 4 for trainees. Actual mortality was below predicted for all surgeons. Morbidity was also lowest for trainees (10%). CONCLUSIONS: With appropriate case selection, trainees in cardiac surgery can achieve good results. As training changes in the UK, trainees should receive increased supervised exposure to a wider range of procedure to compensate for a lower volume of workload.

Adult↗
PubMed2006

Risk stratification of acute pulmonary embolism.

Acute pulmonary embolism (PE) is a potentially life-threatening condition, with an overall 3-month mortality rate of 15% and with right ventricular failure as the most common cause of early death. Risk stratification facilitates identification of high-risk patients and may be helpful in guiding the initial and long-term management. In patients with massive PE and hemodynamic instability, rapid risk assessment is paramount and bedside echocardiography and multislice chest computed tomography (CT) are useful for identifying patients who may benefit from thrombolysis or embolectomy. Cardiac biomarkers, including troponin and the natriuretic peptides, are sensitive markers of right ventricular function. Low levels of troponin, B-type natriuretic peptide (BNP), and NT-terminal proBNP are all highly sensitive assays for identifying patients with an uneventful clinical course. Multislice chest CT is not only useful to diagnose or exclude PE; it also is useful for risk assessment. A right-to-left ventricular dimension ratio > 0.9 on the reconstructed CT four-chamber view identifies patients at increased risk of early death. This article focuses on risk stratification tools, including the clinical examination, electrocardiography, echocardiography, cardiac biomarkers, and chest CT.

Biomarkers↗