Echocardiography in the evaluation of patients with syncope

An unusual cause of syncope: Inferior vena cava compression by a massive renal cyst

Syncope is a commonly encountered symptom that accounts for up to 3% of all emergency department visits in the United States [1]. The differential diagnosis for patients presenting with syncope is often broad and can involve multiple distinct organ systems. This case details the hospital course of an 83-year-old male with a complicated past medical history who initially presented for syncope. Following an extensive work up it was eventually elicited that this patient had an unusual etiology of syncope, a 19 cm x 24 cm renal cyst that was compressing the inferior vena cava (IVC).

Role of Artificial Intelligence in Improving Syncope Management

Syncope is common in the general population and a common presenting symptom in acute care settings. Substantial costs are attributed to the care of patients with syncope. Current challenges include differentiating syncope from its mimickers, identifying serious underlying conditions that caused the syncope, and wide variations in current management. Although validated risk tools exist, especially for short-term prognosis, there is inconsistent application, and the current approach does not meet patient needs and expectations. Artificial intelligence (AI) techniques, such as machine learning methods including natural language processing, can potentially address the current challenges in syncope management. Preliminary evidence from published studies indicates that it is possible to accurately differentiate syncope from its mimickers and predict short-term prognosis and hospitalisation. More recently, AI analysis of electrocardiograms has shown promise in detection of serious structural and functional cardiac abnormalities, which has the potential to improve syncope care. Future AI studies have the potential to address current issues in syncope management. AI can automatically prognosticate risk in real time by accessing traditional and nontraditional data. However, steps to mitigate known problems such as generalisability, patient privacy, data protection, and liability will be needed. In the past AI has had limited impact due to underdeveloped analytical methods, lack of computing power, poor access to powerful computing systems, and availability of reliable high-quality data. All impediments except data have been solved. AI will live up to its promise to transform syncope care if the health care system can satisfy AI requirement of large scale, robust, accurate, and reliable data.

Development and Validation of a Novel Predictive Model for the Early Differentiation of Cardiac and Non-Cardiac Syncope

Background

The diagnosis of cardiac syncope remains a challenge. This study sought to develop and validate a diagnostic model for the early identification of individuals likely to have a cardiac cause.

Methods

877 syncope patients with a determined cause were retrospectively enrolled at a tertiary heart center. They were randomly divided into the training set and validation set at a 7:3 ratio. We analyzed the demographic information, medical history, laboratory tests, electrocardiogram, and echocardiogram by the least absolute shrinkage and selection operator (LASSO) regression for selection of key features. Then a multivariable logistic regression analysis was performed to identify independent predictors and construct a diagnostic model. The receiver operating characteristic curves, area under the curve (AUC), calibration curves, and decision curve analysis were used to evaluate the predictive accuracy and clinical value of this nomogram.

Results

Five independent predictors for cardiac syncope were selected: BMI (OR 1.088; 95% CI 1.022-1.158; P =0.008), chest symptoms preceding syncope (OR 5.251; 95% CI 3.326-8.288; P <0.001), logarithmic NT-proBNP (OR 1.463; 95% CI 1.240-1.727; P <0.001), left ventricular ejection fraction (OR 0.940; 95% CI 0.908-0.973; P <0.001), and abnormal electrocardiogram (OR 6.171; 95% CI 3.966-9.600; P <0.001). Subsequently, a nomogram based on a multivariate logistic regression model was developed and validated, yielding AUC of 0.873 (95% CI 0.845-0.902) and 0.856 (95% CI 0.809-0.903), respectively. The calibration curves showcased the nomogram's reasonable calibration, and the decision curve analysis demonstrated good clinical utility.

Conclusion

A diagnostic tool providing individualized probability predictions for cardiac syncope was developed and validated, which may potentially serve as an effective tool to facilitate early identification of such patients.

Diagnostic approaches to syncope in Internal Medicine Departments and their effect on mortality

Most data on mortality and investigational approaches to syncope comes from patients presented to emergency departments (ED). The aim of this study is to report intermediate term mortality in syncope patients admitted to Internal Medicine Departments and whether different diagnostic approaches to syncope affect mortality. Methods and results A single-center retrospective-observational study conducted at the Tel Aviv "Sourasky" Medical Center. Data was collected from electronic medical records (EMRs), from January 2010 to December 2020. We identified 24,021 patients, using ICD-9-CM codes. Only 7967 syncope patients were admitted to Internal Medicine Departments and evaluated. Logistic regression models were used to determine the effects of diagnostic testing per patient in each department on 30-day mortality and readmission rates. All-cause 30-day mortality rate was 4.1%. There was a significant difference in the number of diagnostic tests performed per patient between the different departments, without affecting 30-day mortality. The 30-day readmission rate was 11.4%, of which 4.4% were a result of syncope. Conclusion Syncope patients admitted to Internal Medicine Departments show a 30-day all-cause mortality rate of ∼4%. Despite the heterogeneity in the approach to the diagnosis of syncope, mortality is not affected. This novel information about syncope patients in large Internal Medicine Departments is further proof that the diagnosis of syncope requires a logic, personalized approach that focuses on medical history and a few tailored, diagnostic tests.

The effect of age and sex on the diagnostic yield of the echocardiogram in patients with syncope

INTRODUCTION

Syncope is the motivation for numerous diagnostic tests, among them transthoracic echocardiography (TTE); however, previous evidence suggests there is little utility in this test. Our objective was to assess its diagnostic yield in syncope, analysing the effect of age and sex.

MATERIAL AND METHODS

We conducted an observational study that included patients with syncope and who underwent TTE between 1990-2015. We defined diagnostic findings related to syncope and performed a descriptive analysis, assessing the diagnostic yield (overall and according to age and sex).

RESULTS

The study included 3,302 patients and measured a diagnostic yield of 8.8%; the most common finding was ventricular dysfunction (4.5%). The probability of a diagnostic TTE significantly increased with age (p<.001) but was low for patients younger than 50 years (2.3%). The male sex was significantly related with a diagnostic TTE (p<.001), mostly due to the higher rate of ventricular dysfunction.

CONCLUSIONS

The diagnostic yield of TTE in patients with syncope is moderate, low in patients younger than 50 years and lower in women than in men. These factors should be considered when conducting a diagnostic study of patients with syncope.

The effect of age and sex on the diagnostic yield of the echocardiogram in patients with syncope

INTRODUCTION

Syncope is the motivation for numerous diagnostic tests, among them transthoracic echocardiography (TTE); however, previous evidence suggests there is little utility in this test. Our objective was to assess its diagnostic yield in syncope, analysing the effect of age and sex.

MATERIAL AND METHODS

We conducted an observational study that included patients with syncope and who underwent TTE between 1990 and 2015. We defined diagnostic findings related to syncope and performed a descriptive analysis, assessing the diagnostic yield (overall and according to age and sex).

RESULTS

The study included 3302 patients and measured a diagnostic yield of 8.8%; the most common finding was ventricular dysfunction (4.5%). The probability of a diagnostic TTE significantly increased with age (p<.001) but was low for patients younger than 50 years (2.3%). The male sex was significantly related with a diagnostic TTE (p<.001), mostly due to the higher rate of ventricular dysfunction.

CONCLUSIONS

The diagnostic yield of TTE in patients with syncope is moderate, low in patients younger than 50 years and lower in women than in men. These factors should be considered when conducting a diagnostic study of patients with syncope.

When Is Syncope Arrhythmic?

Cardiac arrhythmia is a common cause of syncope. The prompt identification of arrhythmic syncope has diagnostic and prognostic implications. In this article, an approach to identifying and managing arrhythmic syncope is discussed, including key findings from the history, physical examination, electrocardiogram, role of risk stratification, use of supplemental investigations, and treatment.

Predictors of Clinically Significant Echocardiography Findings in Older Adults with Syncope: A Secondary Analysis

BACKGROUND

Syncope is a common reason for visiting the emergency department (ED) and is associated with significant healthcare resource utilization.

OBJECTIVE

To develop a risk-stratification tool for clinically significant findings on echocardiography among older adults presenting to the ED with syncope or nearsyncope.

DESIGN

Prospective, observational cohort study from April 2013 to September 2016.

SETTING

Eleven EDs in the United States.

PATIENTS

We enrolled adults (=60 years) who presented to the ED with syncope or near-syncope who underwent transthoracic echocardiography (TTE).

MEASUREMENTS

The primary outcome was a clinically significant finding on TTE. Clinical, electrocardiogram, and laboratory variables were also collected. Multivariable logistic regression analysis was used to identify predictors of significant findings on echocardiography.

RESULTS

A total of 3,686 patients were enrolled. Of these, 995 (27%) received echocardiography, and 215 (22%) had a significant finding on echocardiography. Regression analysis identified five predictors of significant finding: (1) history of congestive heart failure, (2) history of coronary artery disease, (3) abnormal electrocardiogram, (4) high-sensitivity troponin-T >14 pg/mL, and 5) N-terminal pro B-type natriuretic peptide >125 pg/mL. These five variables make up the ROMEO (Risk Of Major Echocardiography findings in Older adults with syncope) criteria. The sensitivity of a ROMEO score of zero for excluding significant findings on echocardiography was 99.5% (95% CI: 97.4%-99.9%) with a specificity of 15.4% (95% CI: 13.0%-18.1%).

CONCLUSIONS

If validated, this risk-stratification tool could help clinicians determine which syncope patients are at very low risk of having clinically significant findings on echocardiography.

REGISTRATION

ClinicalTrials.gov Identifier NCT01802398.

Trends in use of echocardiography in hospitalized patients with syncope

PURPOSE

We sought to assess the trends in use, predictors of echocardiography, and its impact on in-hospital mortality in patients admitted with syncope using a large national database.

METHODS

Utilizing the Nationwide Inpatient Sample (NIS) database from 2001 to 2014, we identified adult patients (>18 years) with a primary discharge diagnosis of syncope and use of echocardiogram was ascertained.

RESULTS

A total of 3 174 619 patients with a primary discharge diagnosis of syncope were identified, of which 184 167 (5.8%) underwent an echocardiogram. The rate of syncope hospitalization remained constant between 2001 and 2009 (1.1/1000 US population) but has since decreased steadily to about 0.5/1000 US population in 2014. After adjusting for patient and hospital characteristics, the rate of echocardiogram use increased significantly from 5.1% in 2001 to 6.8% in 2014 (2.7% relative increase per year [P_trend  = 0.024]). Predictors of use were cardiac disorders, hypertension, diabetes, peripheral vascular disease, and renal failure. After adjusting for baseline risk, use of echocardiography was not associated with in-hospital mortality (OR = 0.827, P = 0.155), but was associated with a 14.6% increase in adjusted length of stay and a 22.6% increase in adjusted hospital cost compared to no echocardiography use (both P < 0.001).

CONCLUSIONS

The admission rates for syncope are decreasing and use of echocardiography in hospitalized patients with syncope is appropriately low. Given the lack of any favorable impact on mortality and the association with increased costs, there is a continued need to emphasize evidence-based use of echocardiography in patients presenting with syncope.

Utilization of Echocardiogram, Carotid Ultrasound, and Cranial Imaging in the Inpatient Investigation of Syncope: Its Impact on the Diagnosis and the Patient's Length of Hospitalization

Background

Although guidelines suggest that the best strategy for evaluating syncope is clinical history and physical examination, the inappropriate utilization of diagnostic imaging is common.

Methods

A single center retrospective analysis conducted in adult patients admitted for evaluation and management of syncope for a period of 12 months. Charts were reviewed to abstract demographic data, admitting and discharge diagnosis, diagnostic investigatory tests including imaging modalities (echocardiogram, carotid ultrasound, and cranial computed tomography (CT)) ordered, subspecialty consultation requested, treatment rendered and hospital length of stay (LOS).

Results

A total of 109 patients were admitted for syncope, mean age was 68.74 ± 21.04 years and 39.44% were men. Echocardiogram, carotid ultrasound, and cranial CT were ordered in 69.72%, 33.02%, and 76.14% respectively. The mean hospital LOS was 2.6 days. Patients with no imaging test, one imaging test, two imaging tests, and three imaging tests ordered have an average hospital LOS of 2.22 days, 2.44 days, 2.58 days, and 3.07 days respectively. The number of imaging test and its relation to the admitting (Chi-square (chi-sq) P = 0.4165, nominal logistic regression (LR) P = 0.939) and discharge (chi-sq P = 0.1507, nominal LR P = 0.782) diagnosis as well as the LOS in relation to the number of imaging test ordered (analysis of variance (ANOVA) P = 0.368, Kruskal Wallis (KW) P = 0.352) were not statistically significant although there was a trend of prolonged hospital LOS the more imaging diagnostic test had been ordered. Syncope was the admitting and discharge diagnosis in 89.9% and 91.74% respectively.

Conclusions

Choosing the appropriate diagnostic tests as dictated by the patient’s clinical manifestation and utilizing less expensive test would be appropriate and cost-effective approach in appraising patients with syncope.

Variation in diagnostic testing for older patients with syncope in the emergency department

BACKGROUND

Older adults presenting with syncope often undergo intensive diagnostic testing with unclear benefit. We determined the variation, frequency, yield, and costs of tests obtained to evaluate older persons with syncope.

METHODS

We conducted a prospective, multicenter observational cohort study in 11 academic emergency departments in the United States of 3686 patients aged ≥60 years presenting with syncope or presyncope. We measured the frequency, variation, yield, and costs (based on Medicare payment tables) of diagnostic tests performed at the index visit.

RESULTS

While most study rates were similar across sites, some were notably discordant (e.g., carotid ultrasound: mean 9.5%, range 1.1% to 49.3%). The most frequently-obtained diagnostic tests were initial troponin (88.6%), chest x-ray (75.1%), head CT (42.5%) and echocardiogram (35.5%). The yield or proportion of abnormal findings by diagnostic test ranged from 1.9% (electrocardiogram) to 42.0% (coronary angiography). Among the most common tests, echocardiogram had the highest proportion of abnormal results at 22.1%. Echocardiogram was an outlier in total cost at $672,648, and had a cost per abnormal test of $3129.

CONCLUSION

Variation in diagnostic testing in older patients presenting with syncope exists. The yield and cost per abnormal result for common tests obtained to evaluate syncope are also highly variable. Selecting tests based on history and examination while also prioritizing less resource intensive and higher yield tests may ensure a more informed and cost-effective approach to evaluating older patients with syncope.

Things We Do For No Reason: Echocardiogram in Unselected Patients with Syncope

Syncope is a common cause of emergency department visits and hospitalizations. Echocardiogram is frequently used as a diagnostic tool in the evaluation of syncope, performed in 39% to 91% of patients. The diagnostic yield of echocardiogram for detecting clinically important abnormalities in patients with a normal history, physical examination, and electrocardiogram (ECG), however, is extremely low. In contrast, echocardiograms performed on patients with syncope with a positive cardiac history, abnormal examination, and/or ECG identify an abnormality in up to 29% of cases, though these abnormalities are not always defi nitively the cause of symptoms. Recently updated clinical guidelines for syncope management from the American College of Cardiology now recommend echocardiogram only if initial history or examination suggests a cardiac etiology, or ECG is abnormal. Universal echocardiography in patients with syncope exposes a signifi cant number of patients to unnecessary testing and cost and does not represent evidence-based or high-value patient care.

Diagnostic Yield of Echocardiography in Syncope Patients with Normal ECG

Aim. This study aimed to assess the role of echocardiography as a diagnostic tool in evaluating syncope patients with normal versus abnormal electrocardiogram. Methods. We conducted a retrospective study of 468 patients who were admitted with syncope in 2011 at St. Joseph's Regional Medical Center, Paterson, NJ. Hospital records and patient charts, including initial emergency room history and physical, were carefully reviewed. Patients were separated into normal versus abnormal electrocardiogram groups and then further divided as normal versus abnormal echocardiogram groups. Causes of syncope were extrapolated after reviewing all test results and records of consultations. Results. Three hundred twelve of the total patients (68.6%) had normal ECG. Two-thirds of those patients had echocardiograms; 11 patients (5.7%) had abnormal echo results. Of the aforementioned patients, three patients had previous documented history of severe aortic stenosis on prior echocardiograms. The remaining eight had abnormal but nondiagnostic echocardiographic findings. Echocardiography was done in 93 of 147 patients with abnormal ECG (63.2%). Echo was abnormal in 27 patients (29%), and the findings were diagnostic in 6.5% patients. Conclusions. This study demonstrates that echocardiogram was not helpful in establishing a diagnosis of syncope in patients with normal ECG and normal physical examination.

Recommendations for the evaluation and management of observation services: a consensus white paper: the Society of Cardiovascular Patient Care

Observation Services (OS) was founded by emergency physicians in an attempt to manage "boarding" issues faced by emergency departments throughout the United States. As a result, OS have proven to be an effective strategy in reducing costs and decreasing lengths of stay while improving patient outcomes. When OS are appropriately leveraged for maximum efficiency, patients presenting to emergency departments with common disease processes can be effectively treated in a timely manner. A well-structured observation program will help hospitals reduce the number of inappropriate, costly inpatient admissions while avoiding the potential of inappropriate discharges. Observation medicine is a complicated multidimensional issue that has generated much confusion. This service is designed to provide the best possible patient care in a value-based purchasing environment where quality, cost, and patient satisfaction must continually be addressed. Observation medicine is a service not a status. Therefore, patients are admitted to the service as outpatients no matter whether they are placed in a virtual or dedicated observation unit. The key to a successful observation program is to determine how to maximize efficiencies. This white paper provides the reader with the foundational guidance for observational services. It defines how to set up an observational service program, which diagnoses are most appropriate for admission, and what the future holds. The goal is to help care providers from any hospital deliver the most appropriate level of treatment, to the most appropriate patient, in the most appropriate location while controlling costs.

Syncope: diagnosis and management

Syncope is defined as transient loss of consciousness due to global cerebral hypoperfusion. It is characterized by having a relatively rapid onset, brief duration with spontaneous and full recovery. The major challenge in the evaluation of patients with syncope is that most patients are asymptomatic at the time of their presentation. A thorough history and physical examination including orthostatic assessment are crucial for making the diagnosis. After initial evaluation, short-term risk assessment should be performed to determine the need for admission. If the short-term risk is high, inpatient evaluation is needed. If the short-term risk is low, outpatient evaluation is recommended. In patients with suspected cardiac syncope, monitoring is indicated until a diagnosis is made. In patients with suspected reflex syncope or orthostatic hypotension, outpatient evaluation with tilt-table testing is appropriate. Syncope units have been shown to improve the rate of diagnosis while reducing cost and thus are highly recommended.

Priorities for emergency department syncope research

STUDY OBJECTIVES

There is limited evidence to guide the emergency department (ED) evaluation and management of syncope. The First International Workshop on Syncope Risk Stratification in the Emergency Department identified key research questions and methodological standards essential to advancing the science of ED-based syncope research.

METHODS

We recruited a multinational panel of syncope experts. A preconference survey identified research priorities, which were refined during and after the conference through an iterative review process.

RESULTS

There were 31 participants from 7 countries who represented 10 clinical and methodological specialties. High-priority research recommendations were organized around a conceptual model of ED decisionmaking for syncope, and they address definition, cohort selection, risk stratification, and management.

CONCLUSION

We convened a multispecialty group of syncope experts to identify the most pressing knowledge gaps and defined a high-priority research agenda to improve the care of patients with syncope in the ED.

Recognizing life-threatening causes of syncope

While the overall prognosis of syncope is favorable, the identification of individuals with a potentially life-threatening cause is of paramount importance. Cardiac syncope is associated with an elevated risk of mortality, and includes both primary arrhythmic and obstructive etiologies. Identification of these individuals is contingent on careful clinical assessment and judicious use of diagnostic investigations. This article focuses on life-threatening causes of syncope and a diagnostic approach to facilitate their identification.

[Syncope and epileptic seizures]

Syncope is one of the most common symptoms leading to hospital admission. Thereby syncope can be induced by several diseases. It is crucial to detect underlying structural heart disease or high grade arrhythmias, as these are associated with an increased mortality. The careful history and physical examination can often give sufficient evidence to evaluate the origin of syncope. Additional examinations should only be applied selectively. In patients with structural heart disease the specific treatment should be initiated, in patients with cardiac arrhythmias the implantation of a pacemaker or ICD might be indicated. The most common neurally-mediated and orthostatic syncopes can often be treated successfully by physical training. Beside syncope epilepsy might be responsible for a transient loss of consciousness. Again careful history taking helps to differentiate between these two entities.

Role of echocardiography in the evaluation of syncope: a prospective study

OBJECTIVE

To study the role of echocardiography in the stepwise evaluation of syncope.

DESIGN

A prospective observational study with an 18 month follow up.

SETTING

University teaching hospital providing primary and tertiary care.

SUBJECTS

650 consecutive patients with syncope and clinical suspicion of an obstructive valvar lesion, or with syncope not explained by history, physical examination, or a 12 lead ECG, who underwent bidimensional Doppler transthoracic echocardiography.

MAIN OUTCOME MEASURES

The causes of syncope were assigned using published diagnostic criteria. Echocardiography was considered diagnostic when confirming a suspected diagnosis, or when revealing occult cardiac disease explaining the syncope.

RESULTS

A systolic murmur was identified in 61 of the 650 patients (9%). Severe aortic stenosis was suspected in 20 of these and was confirmed by echocardiography in eight. Follow up excluded further cases of aortic stenosis. In patients with unexplained syncope (n = 155), routine echocardiography showed no abnormalities that established the cause of the syncope. Echocardiography was normal or non-relevant in all patients with a negative cardiac history and a normal ECG (n = 67). In patients with a positive cardiac history or an abnormal ECG (n = 88), echocardiography showed systolic dysfunction (left ventricular ejection fraction < or = 40%) in 24 (27%) and minor non-relevant findings in the remaining 64. Arrhythmias were diagnosed in 12 of the 24 patients with systolic dysfunction (50%), and in 12 of the 64 remaining patients (19%) (p < 0.01).

CONCLUSIONS

Echocardiography was most useful for assessing the severity of the underlying cardiac disease and for risk stratification in patients with unexplained syncope but with a positive cardiac history or an abnormal ECG.

Syncope: investigation and treatment

Syncope is a common condition that can be both disabling and expensive to treat. Although investigative modalities are sometimes required, a diagnosis can often be made with a good history and physical exam. Recent reports have identified specific historic features that are more suggestive of cardiac syncope as compared with vasovagal syncope and seizures. Advances in ambulatory electrocardiography (in particular the implantable loop recorder) have proven invaluable in both difficult-to-diagnose syncope, and in advancing our knowledge of its mechanisms. When clear dysrhythmias are manifest, appropriate therapies are self-evident. However, recurrent vasovagal syncope continues to be a condition that can be difficult to treat. Fortunately, there are well-conducted trials of both pharmacologic therapies (b-blockers, alpha agonists, and selective serotonin reuptake inhibitors) and nonpharmacologic treatments (orthostatic physical training and dual-chamber pacemakers) that should provide more guidance in the near future.

Costs and utility of tests in the evaluation of the pediatric patients with syncope

New diagnostic tests have markedly improved the ability to establish a cause of syncope in pediatric patients, but at a substantial cost. The goal of syncope evaluation should be to diagnose treatable causes and identify patients at high risk for sudden death. The diagnostic utility of commonly used tests is reviewed. Although there are limited data on the application of specific diagnostic tests in the child with syncope, most tests have a low yield in unselected patients. A more directed approach to testing, based on the results of history, physical examination and the electrocardiogram is likely to result in significant cost reduction while still identifying patients with life threatening disorders. Validation of such an approach awaits prospective evaluation.

Diagnostic evaluation and management of patients with syncope

This article focuses on the evaluation of patients with syncope, a symptom not a disease. Syncope is a transient loss of consciousness associated with loss of postural tone with spontaneous recovery. The authors discuss the utility of an indications for different diagnostic tests, the indications for hospital admission, and the management of patients with certain known causes of syncope, including vasovagal and arrhythmic.

Syncope

Syncope is a common clinical presentation. Although most commonly benign, it may herald a pathology with a poor prognosis. The work-up of syncope includes a careful history, physical examination, electrocardiogram, risk stratification, and appropriately directed testing. The key factor in the investigation of syncope is the presence (or absence) of structural heart disease or an abnormal electrocardiogram. The most useful investigation in unexplained syncope with a normal heart is the tilt table test for evaluating predisposition to neurocardiogenic (vasovagal) syncope. In the setting of structural heart disease or an abnormal electrocardiogram, electrophysiologic studies play a more important role. The utility of noninvasive cardiac monitoring for symptom-rhythm correlation may be limited by infrequent symptoms. The availability of external and implantable loop recorders allows prolonged periods of monitoring to increase diagnostic yield. The management of patients with syncope may be complex. Early referral to a cardiac electrophysiologist is warranted in patients who are at high risk.

What is the yield of screening echocardiography in pediatric syncope?

OBJECTIVE

To determine the yield of screening echocardiography in the evaluation of pediatric syncope.

DESIGN

All patients diagnosed with syncope from January 1993 to January 1999 were identified and their records were reviewed for age, weight, sex, year of presentation, personal and family history, physical examination, and cardiac diagnostic testing. Cardiac defects were identified by reviewing echocardiograms and reports.

RESULTS

The 480 patients (268 females) ranged in age from 1.5 to 18.0 years old and ranged in weight from 10.3 to 113.6 kg. Final diagnoses included noncardiac causes in 458, long QT syndrome in 14, arrhythmias in 6, and cardiomyopathy in 2. An abnormal history, physical examination, or electrocardiogram identified 21 of the 22 patients with a cardiac cause of syncope. Of the 322 (67%) echocardiograms performed, abnormalities were detected in 37. These abnormalities included 26 minor valve anomalies, 7 hemodynamically insignificant shunt lesions, 2 mildly decreased left ventricular shortening fractions, and 2 cardiomyopathies. Only the 2 cardiomyopathies were considered to be potential causes of syncope, and in both cases, the electrocardiogram was markedly abnormal. A similar percentage of echocardiograms were ordered during the first and last 3 years of the study (61% vs 71%).

CONCLUSION

History, physical examination, and electrocardiography provide a screening protocol that allows the identification of a cardiac cause of syncope in the overwhelming majority of pediatric patients. In the absence of a positive screen result, the echocardiogram does not contribute to the evaluation of syncope in children. We speculate that primary care providers and pediatric cardiologists continue to use echocardiography because of the paucity of data regarding its value in pediatric syncope. However, this study shows little benefit of screening echocardiography and should discourage its routine use.

Pediatric echocardiography: applications and limitations

Echocardiography is an extraordinarily useful imaging technique in fetuses, infants, children, and adolescents. Recent technologic innovations have expanded its versatility in the pediatric population. However, limited societal resources, limitations inherent to ultrasound imaging, and numerous imaging options even within the field of pediatric echocardiography necessitate the discriminate and thoughtful use of echocardiography in children. The clinical assessment remains a critical prelude to echocardiographic examination of the pediatric cardiovascular system.

The high cost of syncope: cost implications of a new insertable loop recorder in the investigation of recurrent syncope

BACKGROUND

Patients with recurrent syncope frequently undergo extensive investigations that consume significant health care resources. Recent advances in long-term monitoring techniques have enhanced diagnostic yield in patients with infrequent symptoms. There is little information on the relative cost-effective profile of the investigative tools used in patients with syncope.

METHODS

Two methods to determine health care costs in patients with syncope were used. In the first, health care resource utilization was determined in 24 patients with recurrent unexplained syncope and negative investigations who underwent insertion of the implantable loop recorder (ILR) during a pilot study of the feasibility of the device. The costs of investigations before, during, and after ILR implantation in each patient were calculated on the basis of median charges for an index investigation and a regression analysis of 1018 US Medicare hospital claims for syncope from 1993. Charges were converted to costs using a cost-to-charge ratio of 0.64. The second method was based on estimated costs per diagnosis and published diagnostic yields of 6 commonly applied tests in patients with syncope. A cohort simulation using theoretic models of 100 patients undergoing investigation for syncope was created to compare the diagnostic yield and cost per diagnosis of various diagnostic cascades.

RESULTS

In the pilot study, the cost of investigation of syncope in the 2 years before ILR insertion was $7584 per patient. After the ILR was inserted, a diagnosis was obtained in 21 of 24 patients (diagnostic yield 88%). The cost of therapy was $2452, followed by a reduction in cost of care to $596 over 30 +/- 10 months of follow-up. In the second method, the diagnostic yield of individual tests ranged from 3% for echocardiography to 88% for the ILR. The cost per diagnosis obtained ranged from $529 for the external loop recorder to $73,260 for electrophysiologic testing in patients without structural heart disease. An approach to syncope similar to that of the ILR pilot study resulted in a cost per diagnosis of $3193 and a diagnostic yield of 98%. Performance of echocardiography in half of the patients and electrophysiologic testing only in the presence of structural heart disease reduced the cost to $2494 and retained a diagnostic yield of 98%.

CONCLUSIONS

The cost of investigation of syncope is high. The ILR may reduce health care resource utilization by providing a diagnosis permitting definitive therapy. The cost per diagnosis profile of current diagnostic tests commonly used in patients with syncope is highly variable. A cost-effective approach to diagnosing this disorder can retain a high diagnostic yield with a reduction in resource utilization compared with a conventional approach.

Syncope: current diagnosis and treatment

The patient with syncope often poses a formidable diagnostic challenge. A large number of underlying causes must be considered, ranging in severity from benign to life-threatening. A careful, systematic clinical evaluation beginning with a history, physical examination, and ECG will establish the diagnosis in most patients, and the judicious use of specialized testing will confirm or uncover the cause in many of the remaining cases. Further basic and clinical research into the pathogenesis and treatment of neurocardiogenic syncope, the role of HUT testing in neurally mediated syncope, and the optimal use of EPS in patients with cardiac disease will markedly improve our management of these patients in the future.