Echocardiographic evaluation of pulmonary embolism and its response to therapeutic interventions

Intraoperative Transesophageal Echocardiography to Monitor for Pulmonary Emboli in a Pediatric Patient Undergoing Undifferentiated Embryonal Sarcoma of the Liver Resection

A minimally invasive monitoring technique, intraoperative transesophageal echocardiography (TEE), has been utilized to provide real-time data on volume status and ventricular function in patients undergoing liver transplantation. In this case, TEE was utilized in an 8-year-old female undergoing undifferentiated embryonal sarcoma of the liver resection to monitor for pulmonary emboli, particularly a saddle embolus. In addition to visualization of cardiac structures, TEE can also be utilized to monitor the liver, lungs, spleen, and kidneys. Monitoring for echocardiographic findings of pulmonary embolism in this high-risk patient was an integral part of effective intraoperative management.

Successful Point-Of-Care Ultrasound-Guided Treatment of Submassive Pulmonary Embolism

Pulmonary embolism is associated with significant mortality and impaired long-term functional outcomes. Timely identification and treatment is crucial for successful management. Unfortunately, prompt diagnosis can be challenging in patients without overt signs of cardiovascular compromise. Point-of-care cardiac ultrasound (POCCUS) can be used to identify signs of acute pulmonary embolism, risk stratify patients for adverse outcomes and assess response to therapy. This report describes a patient with submassive pulmonary embolism and evidence of acute right ventricular strain on POCCUS successfully treated with thrombolytic therapy. The dynamic changes observed on point-of-care ultrasound are presented.

Pulmonary embolism with cardiac arrest: a STEMI patient's unexpected course

We describe the successful use and complications of bolus-dose alteplase to treat strongly suspected pulmonary embolism (PE) with cardiac arrest in a patient initially presenting as ST-elevation myocardial infarcation (MI). Case description is followed by a review of the indications, safety, and dosing of systemic thrombolytic therapy for high-risk PE in the emergency department (ED). Diagnostic and therapeutic approach to PE in critically ill patients is also considered, including the potential utility of point-of-care ultrasound (PoCUS) in the ED.

Practical echocardiographic approach for risk stratification of patients with acute pulmonary embolism

Acute pulmonary embolism remains a common cause of mortality. Early diagnosis and appropriate risk stratification is necessary to individualize treatment strategy. Computed tomography scan of the pulmonary arteries is routinely used to diagnose acute pulmonary embolism and in some cases is useful to assess right ventricular dilation. In patients with acute pulmonary embolism, right ventricular dilation and dysfunction indicates a high-risk situation where immediate administration of thrombolytic agent, catheter-directed thrombolysis, or surgical embolectomy could be considered. A bedside 2D echocardiogram at the time of presentation could provide additional morphological, functional, and hemodynamic parameters including right ventricular dilation, McConnell's sign, reduced tricuspid annular plane systolic excursion (TAPSE), interventricular septal flattening, abnormal right ventricular hemodynamics and in rare cases thrombi in the inferior vena cava, right atrium or ventricle en route to pulmonary arteries may also be visualized. This additional information is useful for selection of appropriate treatment modality. Thus, our objective is to provide a practical echocardiographic approach for risk stratification of patients with acute pulmonary embolism.

Thrombolysis for Right Atrial Thrombus-in-Transit in a Patient With Massive Pulmonary Embolism

Right atrial thrombus is a rare entity frequently encountered in patients with pulmonary embolism. Although the existing guidelines do not offer a clear statement for the management of right atrial thrombus and pulmonary embolism, this condition is associated with worse outcomes. We present a case of a 79-year-old patient presenting with signs suggestive of massive pulmonary embolism who was found to have a right atrial thrombus on transthoracic echocardiogram and was successfully treated with systemic thrombolysis. Despite the lack of data from randomized studies, right atrial thombi in transit should be considered a severe form of thromboembolic disease often requiring aggressive treatment, particularly in patients with severe right ventricular dysfunction.

Importance of clinical and echocardiographic hemodynamic assessment in chronic pulmonary embolism

We describe a 42-year-old man presenting to the emergency department with cardiogenic shock. He had a prior history of acute pulmonary embolism (PE), and had been on anticoagulation for 2 years. Although computed tomographic pulmonary angiography performed at the emergency department showed no change in the extent of PE and did not support a role of surgical treatment, pulmonary embolectomy was recommended by attending physician based on clinical and echocardiographic hemodynamic findings like unstable vital sign and markedly enlarged right ventricle with severely depressed systolic function. Surgery confirmed the presence of fresh thrombi. After surgery, hemodynamic status was progressively improved, but the patient died due to pneumonia and pulmonary hemorrhage.

Successful Treatment of Peripartum Massive Pulmonary Embolism with Extracorporeal Membrane Oxygenation and Catheter-Directed Pulmonary Thrombolytic Therapy

Chronic thromboembolic pulmonary hypertension during pregnancy is uncommon but is associated with maternal mortality in excess of 35%. We report a case of decompensated thromboembolic pulmonary hypertension requiring emergency caesarean section and postpartum treatment with extracorporeal membrane oxygenation and thrombolytic therapy with urokinase. The use of extracorporeal membrane oxygenation, catheter-directed pulmonary thrombolytic therapy and other pulmonary vasodilators for management of this life-threatening disease is discussed.

Critical appraisal on the utility of echocardiography in the management of acute pulmonary embolism

Echocardiography can be used for rapid and accurate risk stratification of patients with pulmonary embolism to appropriately direct the therapeutic strategies for those at high risk. Echocardiography is an ideal risk stratification tool in this regard because of its easy portability to the emergency room or to the bed side. It can be performed at a relatively low cost and at no risk to the patient. Furthermore, echocardiography allows repetitive noninvasive assessment of the cardiovascular and hemodynamic status of the patient and the response to the therapeutic interventions. Right ventricular hypokinesis, persistent pulmonary hypertension, a patent foramen ovale, and a free floating right heart thrombus are echocardiographic markers that identify patients at a higher risk for morbidity and mortality. Such patients warrant special consideration for thrombolysis or embolectomy.

Risk Factors for Mortality in Patients With Cardiac Device-Related Infection

Background— Because of the increased use of pacemakers and implantable cardioverter defibrillators, infection has become a complication with significant morbidity and mortality. Data on risk factors for mortality in patients with cardiac-device related infection are limited. We evaluated the prognostic significance of key clinical and echocardiographic variables in a large retrospective population of patients with cardiac-device related infection.

Methods and Results— Two hundred ten patients with cardiac-device related infection were identified at the University of Michigan between 1995 and 2006. Data were abstracted on key clinical and echocardiographic variables, treatment strategy, and 6-month outcomes. We used multivariable Cox proportional hazards models to examine clinical and echocardiographic variables that were associated with 6-month mortality. Mean age for our study population was 63�17 years, and 72 (44%) were women. All-cause 6-month mortality was 18% (n=37). Independent variables associated with death were systemic embolization (hazard ratio 7.11; 95% CI 2.74 to 18.48), moderate or severe tricuspid regurgitation (hazard ratio 4.24; 95% CI 1.84 to 9.75), abnormal right ventricular function (hazard ratio 3.59; 95% CI 1.57 to 8.24), and abnormal renal function (hazard ratio 2.98; 95% CI 1.17 to 7.59). Size and mobility of cardiac device vegetations were not independently associated with mortality.

Conclusions— We identified several clinical and echocardiographic variables that identify patients with cardiac-device related infection who are at high-risk for mortality and may benefit from more aggressive evaluation.

Echocardiography practice, training and accreditation in the intensive care: document for the World Interactive Network Focused on Critical Ultrasound (WINFOCUS)

Echocardiography is increasingly used in the management of the critically ill patient as a non-invasive diagnostic and monitoring tool. Whilst in few countries specialized national training schemes for intensive care unit (ICU) echocardiography have been developed, specific guidelines for ICU physicians wishing to incorporate echocardiography into their clinical practice are lacking. Further, existing echocardiography accreditation does not reflect the requirements of the ICU practitioner. The WINFOCUS (World Interactive Network Focused On Critical UltraSound) ECHO-ICU Group drew up a document aimed at providing guidance to individual physicians, trainers and the relevant societies of the requirements for the development of skills in echocardiography in the ICU setting. The document is based on recommendations published by the Royal College of Radiologists, British Society of Echocardiography, European Association of Echocardiography and American Society of Echocardiography, together with international input from established practitioners of ICU echocardiography. The recommendations contained in this document are concerned with theoretical basis of ultrasonography, the practical aspects of building an ICU-based echocardiography service as well as the key components of standard adult TTE and TEE studies to be performed on the ICU. Specific issues regarding echocardiography in different ICU clinical scenarios are then described. Obtaining competence in ICU echocardiography may be achieved in different ways - either through completion of an appropriate fellowship/training scheme, or, where not available, via a staged approach designed to train the practitioner to a level at which they can achieve accreditation. Here, peri-resuscitation focused echocardiography represents the entry level--obtainable through established courses followed by mentored practice. Next, a competence-based modular training programme is proposed: theoretical elements delivered through blended-learning and practical elements acquired in parallel through proctored practice. These all linked with existing national/international echocardiography courses. When completed, it is anticipated that the practitioner will have performed the prerequisite number of studies, and achieved the competency to undertake accreditation (leading to Level 2 competence) via a recognized National or European examination and provide the appropriate required evidence of competency (logbook). Thus, even where appropriate fellowships are not available, with support from the relevant echocardiography bodies, training and subsequently accreditation in ICU echocardiography becomes achievable within the existing framework of current critical care and cardiological practice, and is adaptable to each countrie's needs.

Thromboembolism in pregnancy

Venous thromboembolism in pregnancy is a clinical emergency that has been associated with significant risk for maternal and fetal morbidity and mortality. The adaptation of the maternal hemostatic system to pregnancy predisposes women to an increased risk of thromboembolism. A timely diagnosis of deep venous thrombosis is crucial because up to 24% of patients with untreated deep venous thrombosis develop a pulmonary embolism. Recent clinical guidelines identify compression venous ultrasound as the best way to diagnose deep venous thrombosis in pregnancy and CT pulmonary angiography as the best way to diagnose pulmonary embolism in pregnancy. Therapy involves supportive care and anticoagulation with unfractionated or low molecular weight heparin, depending on the clinical scenario.

Lungenembolie

In the population the annual incidence of pulmonary embolism amounts to 1.3-2.8 per 1000 at the age of 65-89 years. Mortality reaches about 17% within the first 3 months. Acute pulmonary embolism is characterized by an increase in pulmonary arterial pressure and an impairment of the pulmonary gas exchange. Elevation of the right cardiac pressure up to right heart decompensation may follow. In addition, hypoxemia, hyperventilation, dead space ventilation, right to left shunting, bronchoconstriction, and vasoconstriction may occur. Clinical examination, ECG, laboratory findings such as elevated D-dimer, blood gas analysis, ultrasound examination of the veins of the lower extremities, and transthoracic echocardiography are acutely available diagnostic methods of an emergency department. In addition, extensive diagnostic procedures like pulmonary scintigraphy and pulmonary angiography may be required. The aim is to get a definite diagnosis as quickly as possible to direct therapy. In acute pulmonary embolism with cardiac shock, monitoring and stabilization of the circulatory function as well as an appropriate anticoagulant therapy are essential. In some cases surgery or a local fibrinolytic intervention is indicated.

Intractable intraoperative hypoxemia secondary to pulmonary embolism in the presence of undiagnosed patent foramen ovale

The management of a patient with hip fracture during general anesthesia, who developed severe intractable hypoxemia caused by intraoperative pulmonary embolism in the presence of undiagnosed patent foramen ovale, is described. The role of urgent intraoperative transesophageal echocardiography in situations where acute perioperative pulmonary embolism/patent foramen ovale is suspected is emphasized.

Natural History of Right Ventricular Dysfunction After Acute Pulmonary Embolism

BACKGROUND

Acute pulmonary embolism (PE) associated with right ventricular (RV) dysfunction has an adverse prognosis. We investigated individual parameters of RV dysfunction after acute PE, assessing their correlation with the PE extent and recovery during 6 months.

METHODS

In all, 35 patients (age 63 +/- 18 years) with acute PE were prospectively investigated for 6 months with serial echocardiography, incorporating longitudinal myocardial-velocity and strain imaging. The extent of PE was quantified on day 1 by ventilation/perfusion pulmonary scintigraphy with PE defined as large when there was greater than 30% lung involvement.

RESULTS

PE extent correlated strongly with a number of parameters of RV function, and the strongest univariate correlates were tricuspid annular motion (TAM) (r = -0.65, P < .0001) and the ratio of RV apical to RV basal systolic velocity (r = 0.66, P < .0001). Multivariate analysis identified TAM (P < .0001) and RV basal late-diastolic velocity (P = .01) as independently predicting PE extent, with a combined correlation (R2 = 0.52, P < .0001). A TAM of less than 2.0 cm had sensitivity, specificity, and positive- and negative-predictive values of 75%, 84%, 75%, and 79%, respectively, in predicting large PE. Prospective follow-up identified that RV:left ventricular end-diastolic area ratio returned to normal within 6 weeks, whereas TAM and ratio of RV apical to RV basal systolic velocity normalized after 3 to 6 months.

CONCLUSION

TAM and ratio of RV apical to RV basal systolic velocity are useful indicators of the extent of PE, and provide unique insights into the recovery of RV function after acute PE.

Acute Pulmonary Embolism on MDCT of the Chest: Prediction of Cor Pulmonale and Short-Term Patient Survival from Morphologic Embolus Burden

OBJECTIVE

To predict cor pulmonale and short-term outcome in patients with pulmonary embolism (PE), we retrospectively investigated three morphology-based MDCT systems for scoring pulmonary artery obstruction.

MATERIALS AND METHODS

Eighty-nine consecutive patients (51 men and 38 women; age range, 23-83 years; median, 63.3 years) with an MDCT diagnosis of acute PE were included in the study. Sixty-four patients had a coexisting malignancy. PE severity was assessed by two masked observers using three percentage arterial obstruction indexes: two severity scores adapted from conventional angiography (excluding and including arterial branch obstruction grading: scores A and B, respectively) and a CT-derived severity score (index C). Echocardiographic reports were reviewed for elevation of right ventricular pressure. Obstruction index results were analyzed for correlation with pulmonary artery pressures and for prediction of cor pulmonale and 30-day survival. Statistical analysis included kappa, analysis of variance, linear correlation, chi-square, and logistic regression tests.

RESULTS

Kappa values of 0.89, 0.82, and 0.78 were obtained for interobserver agreement on PE severity for indexes A, B, and C, respectively. PE severity was moderate but varied significantly between the scores (for index A: median, 25.0%; range, 6.3-100; for index B: median, 12.5%; range, 3.1-65.6; for index C: median, 7.1%; range, 0.65-65.8; p < 0.0001 [analysis of variance]). Index C correlated best with pulmonary artery pressures (r = 0.69; p < 0.0016) and the presence of cor pulmonale (p = 0.0051; odds ratio [OR], 1.20/percentage increase [95% confidence interval, 1.05-1.35]; for an index C cutoff of 21.3%: p = 0.0001; positive predictive value, 1; negative predictive value, 0.87). Eight patients died within 30 days after CT. The PE severity of indexes A and B was not associated with patient outcome (p > 0.05). With score C, PE severity was a significant predictor of early death (p = 0.018; OR, 1.03/percentage increase [95% confidence interval, 1.00-1.06]; for an index C cutoff of 21.3%: p = 0.018; overall OR, 6.77; positive predictive value, 0.24; negative predictive value, 0.96).

CONCLUSION

Mastora score was a significant predictor of cor pulmonale and short-term outcome and may therefore allow therapy and risk stratification in patients with acute PE.

An unusual clinical presentation resembling superior vena cava syndrome post heart surgery

Background

An unusual sequence of post operative events heralded by hemodynamic deterioration followed by dyspnea and rapidly progressive dilatation of superficial neck and facial veins, resembling a superior vena cava syndrome, two days post surgical resection of filamentous aortic valve masses, closure of a patent foramen ovale, and performance of a modified Maze procedure for atrial fibrillation in a patient that presented with transient neurologic findings is presented.

Case Presentation

Although both clinical findings and hemodynamic derangements completely resolved following tricuspid valve repair aimed to correct the new onset severe tricuspid regurgitation noted post operatively; a clear mechanism was not readily obvious and diagnostic testing data somewhat conflictive. We present a careful retrospective examination of all clinical data and review possible clinical entities that could have been implicated in this particular case and recognize that transesophageal echocardiographic findings were most useful in identifying the best course of action.

Conclusion

After reviewing all clinical data and despite the inconclusive nature of test results; the retrospective examination of transesophageal echocardiographic findings proved to be most useful in identifying the best course of action. We postulate that in our case, resolution of the suspected pulmonary embolism with anticoagulation and reestablishment of a normal right ventricular geometry with tricuspid valve repair worked in unison in restoring normal hemodynamics and resolving both dyspnea and venous dilatation.

Elevated Brain Natriuretic Peptide and Troponin I in a Woman with Generalized Weakness and Chest Pain

We report the case of a female patient emergently transferred to our institution with the presumptive diagnosis of myocardial infarction in heart failure given the constellation of symptoms and abnormal laboratory cardiac markers on presentation. However, on closer examination, prior to instituting an invasive cardiac work-up, pulmonary embolism was instead strongly considered to explain a common etiology. Therefore, an echocardiogram was promptly obtained, which revealed the presence of McConnell's sign. This noninvasive imaging modality proved to be critical in the prompt recognition and management of this patient. We reviewed the literature regarding the use of echocardiography and the clinical significance of abnormal cardiac markers in patients presenting pulmonary embolism.

CT imaging in acute pulmonary embolism: diagnostic strategies

Computed tomography pulmonary angiography (CTA) has increasingly become accepted as a widely available, safe, cost-effective, and accurate method for a quick and comprehensive diagnosis of acute pulmonary embolism (PE). Pulmonary catheter angiography is still considered the gold standard and final imaging method in many diagnostic algorithms. However, spiral CTA has become established as the first imaging test in clinical routine due to its high negative predictive value for clinically relevant PE. Despite the direct visualization of clot material, depiction of cardiac and pulmonary function in combination with the quantification of pulmonary obstruction helps to grade the severity of PE for further risk stratification and to monitor the effect of thrombolytic therapy. Because PE and deep venous thrombosis are two different aspects of the same disease, additional indirect CT venography may be a valuable addition to the initial diagnostic algorithm-if this was positive for PE-and demonstration of the extent and localization of deep venous thrombosis has an impact on clinical management. Additional and alternate diagnoses add to the usefulness of this method. Using advanced multislice spiral CT technology, some practitioners have advocated CTA as the sole imaging tool for routine clinical assessment in suspected acute PE. This will simplify standards of practice in the near future.

Severity assessment of acute pulmonary embolism: Role of CT angiography

Helical CT has gained wide acceptance in the noninvasive diagnosis of acute pulmonary embolism (APE) and has therefore largely replaced conventional pulmonary angiography as well as ventilation perfusion scan in the work-up of patients suspected of nonsevere pulmonary embolism (PE). Massive PE is life-threatening; its occurrence may require aggressive treatment such as thrombolysis or embolectomy. Identification of patients suffering from major thromboembolic events based solely on clinical grounds may, however, be difficult. Acute right heart failure is the principal cause of circulatory collapse and death for patients with massive PE, and rapid and specific diagnosis and therapy are required in such patients. Bedside echocardiography, a commonly performed first-line examination, demonstrates signs of cor pulmonale, if present, and can identify large central thrombi. However, echocardiography has limitations. In this review, our goal is to discuss the potential role of CT in assessing patients with severe APE. CT evaluation is based on the direct quantification of pulmonary arterial bed obstruction using various scores and the evaluation of morphological heart changes indicating acute cor pulmonale.

Acute pulmonary embolism

Deep vein thrombosis (DVT) and, therefore, pulmonary embolism (PE) are often preventable. Because of the lack of specificity of symptoms and signs, DVT and PE are frequently clinically unsuspected, leading to substantial diagnostic and therapeutic delays and resulting in considerable morbidity and mortality. Furthermore, prophylaxis continues to be dramatically underused. The incidence of venous thromboembolism is high in hospitalized patients, and both surgical as well as medical patients are at risk.

Echocardiography in pulmonary vascular disease

The assessment of pulmonary artery pressure, right ventricular function, right ventricular filling pressure, and tricuspid regurgitation provides invaluable information in the care of patients with pulmonary vascular disease. Echocardiography provides a rapid, noninvasive, portable, and accurate method to evaluate these parameters and also provides information on left ventricular and valvular function. Echocardiography has therefore become one of the most commonly performed diagnostic studies in patients with pulmonary vascular disease, and the technique's applications in this area are likely to grow. This article presents an overview of the current uses of echocardiography in pulmonary vascular disease and pulmonary hypertension.

Patients with acute pulmonary embolism should have an echocardiogram to guide treatment decisions

A 62-year-old man with a past medical history notable for hypertension, osteoarthritis, and calf deep vein thrombosis at age 55 following a total hip arthroplasty presents to the emergency department with acute-onset dyspnea and right-sided pleuritic chest pains. His medications consist of a calcium channel blocker and a COX-2 inhibitor. Pretest clinical suspicion for pulmonary embolism (PE) is high. Ventilation and perfusion lung scintigraphy are interpreted as being high-probability for PE. The nurse asks if a stat transthoracic echocardiogram should be ordered.

Severity assessment of acute pulmonary embolism: evaluation using helical CT

The objective was to evaluate the helical CT (HCT) criteria that could indicate severe pulmonary embolism (PE). In a retrospective study, 81 patients (mean age 62 years) with clinical suspicion of PE explored by HCT were studied. The patients were separated into three different groups according to clinical severity and treatment decisions: group SPE included patients with severe PE based on clinical data who were treated by fibrinolysis or embolectomy ( n=20); group NSPE included patients with non-severe PE who received heparin ( n=30); and group WPE included patients without PE ( n=31). For each patient we calculated a vascular obstruction index based on the site of obstruction and the degree of occlusion in the pulmonary artery. We noted the HCT signs, i.e., cardiac and pulmonary artery dimensions, that could indicate acute cor pulmonale. According to multivariate analysis, factors significantly correlated with the severity of PE were: the vascular obstruction index (group SPE: 54%; group NSPE: 24%; p<0.001); the maximum minor axis of the left ventricle (group SPE: 30.2 mm; group NSPE: 40.4 mm; p<0.001); the diameter of the central pulmonary artery (group SPE: 32.4 mm; group NSPE: 28.3 mm; p<0.001); the maximum minor axis of the right ventricle (group SPE: 47.5 mm; group NSPE: 42.7 mm; p=0.029); the right ventricle/left ventricle minor axis ratio (group SPE: 1.63; group NSPE: 1.09; p<0.0001). Our data suggest that hemodynamic severity of PE can be assessed on HCT scans by measuring four main criteria: the vascular obstruction index; the minimum diameter of the left ventricle; the RV:LV ratio; and the diameter of the central pulmonary artery.

Diagnostic utility of echocardiography in patients with suspected pulmonary embolism

The aim of this study was to investigate the clinical utility of echocardiography in the diagnosis of pulmonary embolism (PE). For this, we enrolled 162 patients with suspected PE in a prospective study. We evaluated the sensitivity and specificity of right ventricular dilatation, the Doppler evidence of pulmonary hypertension, and their possible associations. We also calculated the number of lung-scan angiography procedures avoided and the number of patients unnecessarily treated when echocardiography was included in the diagnostic work-up. The sensitivity and specificity of echocardiography ranged between 29 and 52% and between 96% and 87%, respectively. Adding echocardiography to the diagnostic strategy for PE would avoid about 12 to 28% of lung-scan angiography procedures, but would cause inappropriate treatment of 4 to 14% of all treated patients. The clinical utility of echocardiography in the diagnosis of PE is limited. The reduction in the number of standard diagnostic procedures obtained through its use would be counterbalanced by an excess of patients inappropriately treated.

Venous thromboembolism in intensive care patients

Venous thromboembolism frequently complicates the management of patients with severe medical and surgical illnesses. Because the diagnosis of VTE is especially challenging in critically ill patients, the focus of intensivists should be on characterization of risk factors and the appropriate choice of VTE prophylaxis. LDUH or LMHW is the preferred choice for VTE prophylaxis in ICU patients. Mechanical methods of prophylaxis should be reserved for patients with a high risk for bleeding. The effectiveness of mechanical methods and of combined strategies of prevention and the clinically important outcomes of therapy need to be explored further in critically ill patients. Few diagnostic strategies have been assessed in ICU patients with suspected PE. Ventilation-perfusion lung scans remain a pivotal diagnostic test but retain the same limitations in critically ill patients as seen in other patient populations. Newer noninvasive techniques, such as spiral CT associated with imaging of the extremities, are gaining more wide-spread use, but, thus far, pulmonary angiography remains the most reliable technique to confirm or exclude PE in patients with respiratory failure. A consensus must be reached regarding the most appropriate combination of tests for adequate and cost-effective diagnosis of VTE. Further investigation of diagnostic strategies that include adequate consideration of clinical diagnosis using standardized models and noninvasive imaging are warranted.

Major pulmonary embolism: review of a pathophysiologic approach to the golden hour of hemodynamically significant pulmonary embolism

Major pulmonary embolism (PE) results whenever the combination of embolism size and underlying cardiopulmonary status interact to produce hemodynamic instability. Physical findings and standard data crudely estimate the severity of the embolic event in patients without prior cardiopulmonary disease (CPD) but are unreliable indicators in patients with prior CPD. In either case, the presence of shock defines a threefold to sevenfold increase in mortality, with a majority of deaths occurring within 1 h of presentation. A rapid integration of historical information and physical findings with readily available laboratory data and a structured physiologic approach to diagnosis and resuscitation are necessary for optimal therapeutics in this "golden hour." Echocardiography is ideal because it is transportable, and is capable of differentiating shock states and recognizing the characteristic features of PE. Spiral CT scanning is evolving to replace angiography as a confirmatory study in this population. Thrombolytic therapy is acknowledged as the treatment of choice, with embolectomy reserved for those in whom thrombolysis is contraindicated.

New CT index to quantify arterial obstruction in pulmonary embolism: comparison with angiographic index and echocardiography

OBJECTIVE

This study was designed to define and evaluate a specific index to quantify arterial obstruction with helical CT in acute pulmonary embolism.

MATERIALS AND METHODS

Fifty-four patients (mean age, 56 years) with proven pulmonary emboli among 158 consecutive patients, who had undergone both CT and pulmonary angiography for clinically suspected pulmonary embolism, were eligible for the study. The CT obstruction index was defined as (n. d) (n, value of the proximal clot site, equal to the number of segmental branches arising distally; d, degree of obstruction scored as partial obstruction [value of 1] or total obstruction [value of 2]). We compared the CT obstruction index with pulmonary arterial obstruction on angiography (assessed by the Miller index), using linear regression, and correlated it with findings on echocardiography. Interobserver variability was determined for both CT and pulmonary angiography indexes.

RESULTS

The CT obstruction index (29% +/- 17%) and the Miller index (43% +/- 25%) were well correlated (r = 0.867, p < 0.0001) with an excellent concordance between investigators for both the CT index (r = 0.944, p < 0.0001) and the Miller index (r = 0.904, p < 0.0001). A CT obstruction index greater than 40% identified more than 90% of patients with right ventricular dilatation.

CONCLUSION

The degree of arterial obstruction in pulmonary embolism may be quantified by a specific CT index that appears reproducible and highly correlated to the previously described index with pulmonary angiography. Further evaluations are needed to investigate the usefulness of the CT obstruction index for stratification of patient risk and determining therapeutic options.

Thrombolysis or heparin therapy in massive pulmonary embolism with right ventricular dilation: results from a 128-patient monocenter registry

STUDY OBJECTIVES

To assess the potential benefit of thrombolysis in patients with massive pulmonary embolism (PE) with stable hemodynamics and right ventricular dysfunction.

DESIGN

Retrospective, cohort study.

SETTING

University-based, tertiary referral medical center.

PATIENTS

One hundred fifty-three consecutive patients with massive PE from January 1992 to December 1997 treated with heparin or thrombolysis.

MEASUREMENTS AND RESULTS

Massive PE was confirmed by perfusion lung scan or pulmonary angiography. Right ventricular dysfunction was assessed by echocardiography (right ventricular/left ventricular [RV/LV] diastolic diameter ratio > 0.6) in all patients. In order to study a homogeneous population, 64 patients treated with thrombolysis (group 1) were matched on baseline RV/LV diameter ratio to 64 patients treated with heparin (group 2). Perfusion lung scan was repeated at day 7 to day 10. Mean relative improvement in perfusion lung scans was higher in group 1 than group 2 (54% vs 42%, respectively). PE recurrences were the same in both groups (4.7%; n = 3). There were no bleeding complications and no deaths in group 2. Conversely, in group 1, 15.6% (n = 10) of patients suffered from bleeding (4.7%; n = 3 with intracranial bleeding) and 6.25% (n = 4) of them died.

CONCLUSIONS

The results of this monocenter registry do not support the indication for thrombolysis in patients suffering from massive PE with stable hemodynamics and right ventricular dysfunction. Appropriate therapy in such patients still remains unknown. Further prospective randomized trials should be performed.

Transthoracic echocardiographic demonstration of massive pulmonary thrombus caused by protein C deficiency

Few cases of pulmonary embolism detected by transthoracic echocardiography (TTE) have been reported. We present a case of a patient affected by pulmonary embolism caused by protein C deficiency. Transthoracic echocardiography showed a thrombus in transit (ie, visualization of a thrombus within the pulmonary artery). A hypercoagulable state caused by deficiency of protein C is a rare cause of pulmonary thromboembolism. Our experience demonstrates a massive pulmonary thrombus resulting from such a deficiency. Transthoracic echocardiography should be considered as the first diagnostic method for patients with suspected pulmonary embolism.

Streptokinase and Heparin versus Heparin Alone in Massive Pulmonary Embolism: A Randomized Controlled Trial

To test the efficacy of thrombolytic therapy in massive pulmonary embolism, we conducted a prospective randomized controlled trial. Eight patients were randomized to receive either 1,500,000 IU of streptokinase in 1 hour through a peripheral vein followed by heparin or heparin alone. All patients had major risk factors for deep vein thrombosis (DVT) and were considered to have high clinical suspicion for pulmonary embolism (PE). At baseline all patients had a similar degree of systemic arterial hypotension, pulmonary arterial hypertension, and right ventricular dysfunction. The time of onset of cardiogenic shock in both groups was comparable (2.25 +/- 0.5 hours in the streptokinase group and 1.75 +/- 0.96 hours in the heparin group). The four patients who were randomized to streptokinase improved in the first hour after treatment, survived, and in 2 years of follow-up are without pulmonary arterial hypertension. All four patients treated with heparin alone died from 1 to 3 hours after arrival at the emergency room (p = 0.02). Post-thrombolytic therapy the diagnosis of PE was sustained in the streptokinase group by high probability V/Q lung scans and proven DVT. A necropsy study performed in three patients in the heparin group showed massive pulmonary embolism and right ventricular myocardial infarction, without significant coronary arterial obstruction. The results indicate that thrombolytic therapy reduces the mortality rate of massive acute pulmonary embolism.

Thrombolytic therapy of pulmonary embolism: a comprehensive review of current evidence

Pulmonary embolism (PE) is a common disorder that is accompanied by significant morbidity and mortality. Although anticoagulation is the standard treatment for PE, thrombolytic therapy, with its ability to produce rapid clot lysis, has long been considered an attractive alternative. Although many studies have been performed over the past three decades, however, the indications for the use of thrombolytic agents in patients with PE remain controversial. In this article, we review the medical literature and provide evidence-based guidelines for the use of thrombolytic therapy. We will also discuss the practical aspects of PE thrombolysis.

Tricuspid valve disease. Clinical evaluation, physiopathology, and management

The tricuspid and mitral valves are homologous whose function depends on coordination among components. Isolated tricuspid valve abnormalities are relatively uncommon. Rheumatic disease, chemicals, immunologic and degenerative disorders alter leaflet anatomy and may result in either stenosis, insufficiency or a combination. More often, tricuspid disorders present as a component of congenital syndromes or secondary to pulmonary vascular or let heart disease which alter geometry and function of nonleaflet components.

Diagnostic accuracy of Doppler-echocardiography in unselected patients with suspected pulmonary embolism

This study investigates the diagnostic value of echocardiography in patients with suspected pulmonary embolism. Doppler-echocardiography was performed in fifty consecutive patients, predominantly presenting in the emergency ward, with clinically suspected pulmonary embolism. Patients were classified as having or not pulmonary embolism by a sequential non-invasive strategy including lung scan, D-dimer measurement and lower limb venous compression ultrasonography, pulmonary angiography being performed in case of an inconclusive non-invasive work-up. The prevalence of pulmonary embolism was 36% (18 of 50 patients). Right ventricular dilatation on 2-D echocardiography associated to a tricuspid regurgitation velocity > or =2.7 m/s, corresponding to a pulmonary systolic pressure > or =39 mmHg, were present in 12 of the 18 patients (67%) with and in two of the 32 patients (6.3%) without pulmonary embolism. They were, however, absent in five of the 18 patients (28%), in whom the definite diagnosis of pulmonary embolism was made. The combination of these both echocardiographic criteria yielded a sensitivity of 67% and a specificity of 94%, positive predictive value was 86% and negative predictive value was 83%. The diagnostic performance of these two combined echocardiographic criteria, when present, permitted to reach in patients with a high clinical pre-test probability of pulmonary embolism the post-test probability values above 90%. On the other hand, the absence of these two Doppler-echocardiographic criteria did not allow to exclude pulmonary embolism, except in presence of a low pre-test probability. The findings of our study show that Doppler-echocardiography in patients with high clinical suspicion of pulmonary embolism may represent a potentially useful screening technique for the diagnosis of the disease permitting prompt initiation of treatment. However, the method does not allow to exclude pulmonary embolism in all patients with intermediate or high clinical suspicion of the disease.

Pulmonary embolism: relation between the degree of right ventricle overload and the extent of perfusion defects

BACKGROUND

Inasmuch as the presence of right ventricle (RV) overload in patients with pulmonary embolism (PE) is associated with a bad prognosis, evaluation of RV function in PE is of importance. This study was done to establish if the degree of RV overload can be predicted from the extent of perfusion defects (PDf).

METHODS

One hundred twenty-one consecutive patients with PE diagnosed by lung scintigraphy (LS) were examined by echocardiography Doppler (ED) immediately after diagnosis. PDf were graded visually in categories (LS score 1 = < or =20%, 2 = >20% of total lung area) and on a continuous scale (normal perfusion = 0, no perfusion = 1). The reproducibility of both methods was tested. RV wall motion was assessed on a four-point scale (0 = normal to 3 = severely hypokinetic). The distance from LV posterior wall to RV anterior wall and dimensions of RV and LV were measured. Pulmonary artery systolic pressure (PAsP) was calculated by using the maximum velocity of tricuspid regurgitation.

RESULTS

There were 51 patients with LS score 1 and 70 (58%) with score 2. In comparison with patients with LS score 1, those with score 2 more often had RV hypokinesis 2+ or 3+ (n = 49 vs n = 16) (p < 0.001), larger RV (34 +/- 6 mm [22 to 48] vs 29 +/- 5 [17 to 38]) (SD [range]) (p < 0.001) and higher PAsP (51 +/- 13 mm Hg [21 to 83] vs 42 +/- 14 [20 to 81]) (p < 0.001). The variability in both groups was large. With continuous scaling, PDf averaged 0.3. This was also the value that best discriminated RV hypokinesis 2+ or 3+ in a receiver operating characteristic curve. However, the variability for this scan scoring method was SD 0.073, giving a 95% confidence limit of +/-0.15.

CONCLUSION

There is a significant correlation between RV overload and PDf, but the variability is large; therefore, an estimate of the size of perfusion defects in LS cannot replace ED in the assessment of PAsP and the degree of RV overload in PE.

Association between right ventricular function and perfusion abnormalities in hemodynamically stable patients with acute pulmonary embolism

BACKGROUND/OBJECTIVES

Patients presenting with acute pulmonary embolism associated with hemodynamic compromise exhibit right ventricular enlargement and dysfunction on transthoracic echocardiogram. However, the degree of echocardiographic abnormalities among hemodynamically stable patients without preexisting cardiopulmonary disease during the acute stage of pulmonary embolism, and following treatment, is unknown. Therefore, this study was designed to assess the extent of right ventricular abnormalities detected on transthoracic echocardiogram in patients following acute pulmonary embolism and during treatment with anticoagulation or vena caval interruption. The extent of pulmonary vascular obstruction and complication rate on follow-up were also assessed.

DESIGN/INTERVENTIONS

Sixty-four consecutive hemodynamically stable patients without preexisting known cardiopulmonary disorder presenting with acute pulmonary embolism and undergoing treatment with anticoagulation or inferior vena caval interruption were studied. All subjects underwent a two-dimensional transthoracic echocardiogram within 24 h of diagnosis. The degree of perfusion abnormality on lung scan was quantified. Twenty-six patients underwent follow-up echocardiogram and lung scan at 6 weeks. The echocardiographic findings were compared with those obtained from a group of normal control subjects matched for gender and age.

RESULTS

Although the mean right ventricular end-diastolic areas did not differ (21.9+/-5.2 cm2 vs 20.1+/-2.9 cm2 for control subjects; p=not significant), the right ventricular end-systolic area was larger in comparison to our series of control subjects (14.6+/-5.1 cm2 vs 11.7+/-2.0 cm2; p=0.025). Fractional right ventricular area change was reduced in the patient group compared with the control subjects (34.3+/-9.0% vs 41.3+/-7.0%; p=0.003). The extent of right ventricular end-systolic area enlargement and decrease in fractional area change did not correlate with the degree of pulmonary vascular obstruction. Patients who were restudied at 6 weeks showed minimal improvement in echocardiographic findings, despite almost complete resolution of perfusion defects on lung scan.

CONCLUSIONS

The extent of right ventricular dysfunction in hemodynamically stable, previously normal patients with acute pulmonary embolism does not reflect the extent of the perfusion abnormalities. Further, right ventricular enlargement and systolic dysfunction are present and persistent despite treatment with heparin and warfarin therapy or vena caval interruption.

Use of two-dimensional echocardiography for the diagnosis of pulmonary embolus

We investigated the diagnostic utility of transthoracic echocardiogram (2-D ECHO) in identifying acute right heart strain in patients with suspected pulmonary embolus (PE) undergoing a pulmonary angiogram during their hospitalization. A retrospective case control study was conducted over a 3-year period at a tertiary, community teaching hospital. Patients were eligible if they had a pulmonary angiogram and a transthoracic echocardiogram. Cases were defined as an angiogram positive for PE and controls were defined as an angiogram negative for PE. We excluded cases in which the time interval between 2-D ECHO and angiogram was greater than 2 days. The 2-D ECHO was considered positive for right heart strain if two of the following were present: enlarged right ventricle, moderate or severe tricuspid regurgitation, increased right ventricular pressures, or paradoxical septal wall motion. We were able to identify 71 patients, of whom 24 met our criteria for PE. Of these, 13 had an echocardiogram consistent with our definition of acute right heart strain, for a sensitivity of 0.54. Forty-six of the 47 patients without PE did not have findings of acute right heart strain. The echocardiogram was positive in 14 patients, for a positive predictive value of 0.93. In seven patients with systolic blood pressures of less than 100 mmHg, five had a PE, all of whom met our criteria for acute right heart strain. We conclude that 2-D ECHOs show promise in identifying PE and hemodynamic compromise as a result of PE, and that further studies are warranted.