Diagnostic yield of pulmonary embolism testing in patients presenting to the emergency department with syncope

Diagnostic utility and outcomes of inpatient investigations for syncope in a regional setting

BACKGROUND

Syncope is a common presentation to the emergency department with a wide spectrum of aetiology. The identification of the underlying cause can be diagnostically challenging, as are the choice of investigations and the decision for inpatient versus outpatient disposition.

AIMS

This study aimed to evaluate the aetiology of syncope as documented, the diagnostic yield of inpatient investigations and outcomes for adult patients admitted for syncope.

METHODS

A single-centred, retrospective cohort study was conducted in adult patients admitted for syncope within a 2-year period. A total of 386 patients were identified after exclusion. Information regarding syncope aetiology, investigations and outcomes were established via chart review of electronic records.

RESULTS

The most common cause of syncope was neural-mediated (43%), followed by orthostatic (36.5%) and cardiogenic (20.5%). The investigations performed in order of frequency included: telemetry electrocardiogram (ECG) (75.4%), computed tomography head non-contrast (58.8%), transthoracic echocardiogram (TTE) (20.2%), computed tomography pulmonary angiogram (CTPA) (6.5%), MR brain (3.9%), electroencephalogram (1.3%) and carotid ultrasound (0.3%). Telemetry ECG, TTE and CTPA led to the diagnosis of syncope in a minority of patients only. As a result, 17.5% of patients had a new intervention on discharge, 5.4% were readmitted for syncope and 9.6% of patients died.

CONCLUSIONS

In the context of the inpatient evaluation of syncope, this study supports the use of telemetry ECG and TTE. Neuroimaging demonstrates a low diagnostic yield for the cause of syncope, but it may have a role to play in excluding other pathologies. Our study does not support the routine use of CTPA, EEG or carotid ultrasound in the evaluation of syncope.

Trauma and syncope: looking beyond the injury

Background

42% of the population experience syncope by the age of 70, accounting for up to 6% of hospital admissions that frequently present as falls. The etiologies of some falls are benign, and others, such as cardiac syncope, are associated with a greater mortality and must be identified.

Methods

This review article aims to bridge the literature gap by providing a comprehensive practice review and critical summary of the current syncope guidance relating to the trauma patient.

Results

The National Institute for Health and Care Excellence, the American College of Cardiology, and European Society of Cardiology published syncope risk stratification guidance. The inclusion of certain high-risk features represented in all three guidelines suggests their significance to identify cardiac syncope including heart failure, abnormal vital signs, syncope during exercise with little to no prodrome, family history of sudden cardiac death, and ECG abnormalities. Of 11 syncope risk stratification scoring systems based on these guidelines, only 2 are externally validated in the emergency department, neither of which are validated for major trauma use. Adherence to thorough history-taking, examination, orthostatic blood pressure recording, and an ECG can diagnose the cause of syncope in up to 50% of patients. ECG findings are 95% to 98% sensitive in the detection of serious adverse outcomes after cardiac syncope and should form part of a standardized syncope trauma assessment. Routine blood testing in trauma is often performed despite evidence that it is neither useful nor cost effective, where the screening of cardiac enzymes and D-dimer rarely influences management.

Discussion

In the absence of a gold-standard clinical test to identify the cause of a syncopal episode, standardized syncope guidelines as described in this review could be incorporated into trauma protocols to analyze high-risk etiologies, improve diagnostic accuracy, reduce unnecessary investigations, and develop an effective and safer management strategy.

The Characteristics of Syncope-Related Emergency Department Visits: Resource Utilization and Admission Rate Patterns in Emergency Departments

Background and objective

Decision-making about syncope patients presenting to the emergency department (ED) is challenging since physicians must balance the minimal risks of life-threatening conditions with the unessential use of expensive imaging or unnecessary hospitalizations. This study aimed to determine the characteristics of ED visits, resource utilization, and admission rate patterns related to syncope in the United States (US) during the period 2005-2015.

Methods

Data from the National Hospital Ambulatory Medical Care Survey (NHAMCS) on ED visits during the 11-year period from 2005 to 2015 were retrieved. ED visits for syncope were identified and compared against non-syncope ED visits. The demographic and clinical characteristics of patients, as well data on resource allocation and admission trends were captured and described for the syncope and the non-syncope groups.

Results

Syncope accounted for 1.11% of the total ED visits during the study period from 2005 to 2015. The incidence of syncope-related ED visits was higher among elderly females, whites, and non-Hispanics. The trend of admission rates showed a decline from about 30% in 2005-2010 to less than 20% in 2014 and 2015. Advanced imaging (CT or MRI) was ordered for 34% of syncope patients.

Conclusion

The percentage of syncope-related ED visits remained stable during the study period, but the admission rates declined while the use of advanced imaging in syncope-related ED visits remained substantially high despite the advances in research and availability of clinical guidelines. Future research is needed to rationalize healthcare utilization in syncope-related ED visits and precisely identify the high-risk population.

Thirty-day readmissions due to Venous thromboembolism in patients discharged with syncope

A recent study found that approximately 1 in every 6 patients hospitalized for the 1st episode of syncope had an underlying pulmonary embolism (PE). As current guidelines do not strongly emphasize evaluation for PE in the workup of syncope, we hypothesize that there might be a higher rate of 30-day readmission due to untreated venous thromboembolism (VTE). The objective of this study is to measure the 30-day readmission rate due to VTE and identify predictors of 30-day readmission with VTE among syncope patients. We identified patients admitted with syncope with ICD9 diagnoses code 780.2 in the Nationwide Readmission Database (NRD-2013), Healthcare Cost and Utilization Project (HCUP). The 30-day readmission rate was calculated using methods described by HCUP. Logistic-regression was used to identify predictors of 30-day readmission with VTE. Discharge weights provided by HCUP were used to generate national estimates. In 2013, NRD included 207,339 eligible patients admitted with syncope. The prevalence rates of PE and DVT were 1.1% and 1.4%, respectively. At least one syncope associated condition was present in 60.9% of the patients. Among the patients who were not diagnosed with VTE during index admission for syncope (N = 188,015), 30-day readmission rate with VTE was 0.5% (0.2% with PE and 0.4% with DVT). In conclusion, low prevalence of VTE in patients with syncope and extremely low 30-day readmission rate with VTE argues against missed diagnoses of VTE in index admission for syncope. These results warrant further studies to determine clinical impact of work up for PE in syncope patients without risk factors.