Diagnostic Yield of head Computed Tomography in Patients with Syncope: Sex Differences

BACKGROUND

Syncope is responsible for approximately 1-3% of all emergency department (ED) visits and up to 6% of all hospital admissions in the United States. Although often of no long-term consequence, syncope can be the first presentation of a range of serious conditions such as strokes, tumors, or subarachnoid hemorrhages. Head computed tomography (CT) scanning is therefore commonly ordered in the ED for patients presenting with syncope to rule out any of these conditions, which may present without other associated physical or neurological findings on initial examination. However, the diagnostic yield of head CTs in patients presenting with syncope is unclear.

OBJECTIVES

To determine the diagnostic yield of head CT in the ED in patients with syncope.

METHODS

We conducted an observational analytical retrospective cross-sectional study on 360 patients diagnosed with syncope who underwent a head CT to determine the diagnostic yield of syncope to determine whether head CT is necessary for every patient presenting with syncope to the ED.

RESULTS

The total of new CT findings was 11.4%. Percentages varied between men (12.8%) and women (9.7%), P = 0.353. There were no significant differences between sexes regarding the findings in head CT, yet the incidence increased, especially among elderly males.

CONCLUSIONS

Age had a more significant impact on diagnostic yield of syncope than head CT. The use of a head CT scan as a routine diagnosis tool in patients with syncope is unjustifiable unless there is an indication based on medical history or physical examination.

[CT scan in syncope : diagnostic yield and prescription habits]

Syncope is a frequent reason for emergency department admission. Brain imaging is theoretically not recommended. After exclusion of features orienting towards non-syncopal events, we retrospectively included 206 patients who underwent head CT scans in the University Hospital of Liège for transient loss of consciousness between December 2020 and July 2021. We surveyed physicians involved in the emergency department concerning their imaging prescription habits and motivations. CT diagnostic yield is 1 %. The oncologic background is associated with pathological findings (odds ratio 84,1, p = 0,005). Cervical angio-CT scans only lead to incidental findings and increased dose exposure. Only a minority (6.6 %) of physicians systematically prescribe brain imaging. Radioprotection is an important notion for only 10 % of the less experimented physicians. Obligation of means is an occasional justification for resort to imaging. A prospective decisional rule based on the exclusion of features orienting towards non-syncopal loss of cousciousness, old age and oncologic history might reduce the number of useless scans. Radioprotection is too often neglected by less experimented physicians. Obligation of means should not be mingled with reassurance behaviors as part of defensive medicine.

Comparison between standard and ultrasound-integrated approach for risk stratification of syncope in the emergency department

This prospective cohort enrolled all patients above 16 years of age presenting to the in the emergency department (ED) for a reported syncope was designed to test the accuracy of a point-of-care ultrasound (POCUS) integrated approach in risk stratification. The emergency physician responsible for the patient care was asked to classify the syncope risk after the initial clinical assessment and after performing POCUS evaluation. All risk group definitions were based on the 2018 European Society of Cardiology guidelines. Thirty days after the index event, all participants were followed up to assess the frequency of short-term serious outcomes as defined in the San Francisco Syncope Rule (SFSR) cohorts. We estimated the accuracy of clinical and POCUS-integrated evaluation in predicting SFSR outcomes. Between February 2016 and January 2018, 196 patients were enrolled [109 women (55.6%)]. Median age was 64 years (interquartile range 31 years). After a follow-up of 30 days, 19 patients experienced 20 SFSR outcomes. Positive and negative likelihood ratios were 1.73 (95% CI 0.87-3.44) and 0.84 (95% CI 0.62-1.12) for the clinical evaluation, and 5.93 (95% CI 2.83-12.5) and 0.63 (95% CI 0.45-0.9) for the POCUS-integrated evaluation. The POCUS-integrated approach would reduce the diagnostic error of the clinical evaluation by 4.5 cases/100 patients. This cohort study suggested that the integration of the clinical assessment with POCUS results in patients presenting to the ED for non-high-risk syncope may increase the accuracy of predicting the risk of SFSR outcomes and the usefulness of the clinical assessment alone.

The blood-brain barrier disruption after syncope: a dynamic contrast-enhanced magnetic resonance imaging study: A case report

RATIONALE

Using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), we demonstrated blood-brain barrier (BBB) disruption following syncope.

PATIENT CONCERNS

A 45-year-old man experienced syncope with a chief complaint of syncope (duration: 1 minutes), 1 day before visiting a university hospital for examination. He had no history of medical problems and was not taking any medications. This episode was the first in his lifetime.

DIAGNOSES

After syncope, the patient did not have any illnesses or symptoms, such as headache, cognitive deficits, or somnolence.

INTERVENTIONS

Cardiac evaluation did not reveal any abnormal findings. In addition, in conventional brain and chest computed tomography and brain MRI, no abnormal lesions were observed.

OUTCOMES

DCE-MRI of the patient showed bright blue colored lines within the sulci throughout the cerebral cortex. The regions of interest, including bright blue colored lines, had significantly higher Ktrans values (6.86 times higher) than those in healthy control participants. These findings are indicative of BBB disruption of the vessels in the sulci.

LESSONS

Using DCE-MRI, we demonstrated BBB disruption following syncope. DCE-MRI is a useful tool for the detection of BBB disruption following syncope.

Stress myocardial perfusion imaging in patients presenting with syncope: Comparison of PET vs. SPECT

BACKGROUND

The role of myocardial perfusion imaging (MPI) in patients with suspected coronary artery disease (CAD) presenting with syncope is controversial. We aimed to determine diagnostic yield of MPI for evaluation of syncope in patients without known CAD, as a function of pre-test patient risk and test modality (PET vs SPECT).

METHODS

Between 1/2010 and 12/2016, 1324 consecutive patients presenting with syncope without known CAD underwent MPI with PET (n = 640) or SPECT (n = 684). Rates of abnormal MPI (summed difference score (SDS) > 2 or left ventricular ejection fraction (LVEF) reserve ≤ 0 for PET and SDS > 2 or post-stress LVEF ≤ 45% for SPECT) were determined among patients stratified by pre-test risk. In patients who were referred for coronary angiography, diagnostic yield of obstructive CAD was calculated in the overall cohort as well as in a propensity-matched cohort compared to patients without syncope.

RESULTS

Abnormal MPI was noted in 36.5% (201/551) of patients who had PET compared with 13.0% (87/671) who had SPECT (P < 0.001), which is largely related to higher comorbidity burden and greater pre-test CAD risk in the PET population. Among patients who had an abnormal MPI, 8.5% (47/551) with PET and 0.7% (5/671) with SPECT were found to have obstructive CAD if referred for coronary angiography. Patients at intermediate-high pre-test risk had a higher proportion of abnormal MPIs and obstructive CAD as compared to those at low risk in both the PET and SPECT cohorts. The rate of abnormal testing and diagnostic yield of PET MPI was similar and proportionate to pre-test likelihood among matched patients with and without syncope.

CONCLUSIONS

Among patients referred for PET MPI with syncope at an intermediate-high pre-test CAD risk, 1 in 3 had an abnormal MPI and 1 in 10 had obstructive CAD. The value of MPI was related to pre-test risk as opposed to the presence of syncope, and MPI testing with PET or SPECT in the low-risk population was low value.

ACR Appropriateness Criteria® Syncope

Syncope and presyncope lead to well over one million emergency room visits in the United States each year. Elucidating the cause of syncope or presyncope, which are grouped together given similar etiologies and outcomes, can be exceedingly difficult given the diverse etiologies. This becomes more challenging as some causes, such as vasovagal syncope, are relatively innocuous while others, such as cardiac-related syncope, carry a significant increased risk of death. While the mainstay of syncope and presyncope assessment is a detailed history and physical examination, imaging can play a role in certain situations. In patients where a cardiovascular etiology is suspected based on the appropriate history, physical examination, and ECG findings, resting transthoracic echocardiography is usually considered appropriate for the initial imaging. While no imaging studies are considered usually appropriate when there is a low probability of cardiac or neurologic pathology, chest radiography may be appropriate in certain clinical situations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Evaluation of Low-Value Diagnostic Testing for 4 Common Conditions in the Veterans Health Administration

IMPORTANCE

Low-value care is associated with harm among patients and with wasteful health care spending but has not been well characterized in the Veterans Health Administration.

OBJECTIVES

To characterize the frequency of and variation in low-value diagnostic testing for 4 common conditions at Veterans Affairs medical centers (VAMCs) and to examine the correlation between receipt of low-value testing for each condition.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used Veterans Health Administration data from 127 VAMCs from fiscal years 2014 to 2015. Data were analyzed from April 2018 to March 2020.

EXPOSURES

Continuous enrollment in Veterans Health Administration during fiscal year 2015.

MAIN OUTCOMES AND MEASURES

Receipt of low-value testing for low back pain, headache, syncope, and sinusitis. For each condition, sensitive and specific criteria were used to evaluate the overall frequency and range of low-value testing, adjusting for sociodemographic and VAMC characteristics. VAMC-level variation was calculated using median adjusted odds ratios. The Pearson correlation coefficient was used to evaluate the degree of correlation between low-value testing for each condition at the VAMC level.

RESULTS

Among 1 022 987 veterans, the mean (SD) age was 60 (16) years, 1 008 336 (92.4%) were male, and 761 485 (69.8%) were non-Hispanic White. A total of 343 024 veterans (31.4%) were diagnosed with low back pain, 79 176 (7.3%) with headache, 23 776 (2.2%) with syncope, and 52 889 (4.8%) with sinusitis. With the sensitive criteria, overall and VAMC-level low-value testing frequency varied substantially across conditions: 4.6% (range, 2.7%-10.1%) for sinusitis, 12.8% (range, 8.6%-22.6%) for headache, 18.2% (range, 10.9%-24.6%) for low back pain, and 20.1% (range, 16.3%-27.7%) for syncope. With the specific criteria, the overall frequency of low-value testing across VAMCs was 2.4% (range, 1.3%-5.1%) for sinusitis, 8.6% (range, 6.2%-14.6%) for headache, 5.6% (range, 3.6%-7.7%) for low back pain, and 13.3% (range, 11.3%-16.8%) for syncope. The median adjusted odds ratio ranged from 1.21 for low back pain to 1.40 for sinusitis. At the VAMC level, low-value testing was most strongly correlated for syncope and headache (ρ = 0.56; P < .001) and low back pain and headache (ρ = 0.48; P < .001).

CONCLUSIONS AND RELEVANCE

In this cohort study, low-value diagnostic testing was common, varied substantially across VAMCs, and was correlated between veterans' receipt of different low-value tests at the VAMC level. The findings suggest a need to address low-value diagnostic testing, even in integrated health systems, with robust utilization management practices.

Near-infrared spectroscopy in evaluating psychogenic pseudosyncope-a novel diagnostic approach

BACKGROUND

Psychogenic pseudosyncope (PPS), a conversion disorder and syncope mimic, accounts for a large proportion of 'unexplained syncope'. PPS is diagnosed by reproduction of patients' symptoms during head-up tilt (HUT). Electroencephalogram (EEG), a time consuming and resource intensive technology, is used during HUT to demonstrate absence of cerebral hypoperfusion during transient loss of consciousness (TLOC). Near-infrared spectroscopy (NIRS) is a simple, non-invasive technology for continuous monitoring of cerebral perfusion. We present a series of patients for whom PPS diagnosis was supported by NIRS during HUT.

METHODS

Eight consecutive patients with suspected PPS referred to a syncope unit underwent evaluation. During HUT, continuous beat-to-beat blood pressure (BP), heart rate (HR) and NIRS-derived tissue saturation index (TSI) were measured. BP, HR and TSI at baseline, time of first symptom, presyncope and apparent TLOC were measured. Patients were given feedback and followed for symptom recurrence.

RESULTS

Eight predominantly female patients (6/8, 75%) aged 31 years (16-54) were studied with (5/8, 63%) having comorbid psychiatric diagnoses, and (5/8, 63%) presenting with frequent episodes of prolonged TLOC with eyes closed (6/8, 75%). All patients experienced reproduction of typical events during HUT. Systolic BP (mmHg) increased from baseline (129.7 (interquartile range [IQR] 124.9-133.4)) at TLOC (153.0 (IQR 146.7-159.0)) (P-value = 0.012). HR (bpm) increased from baseline 78 (IQR 68.6-90.0) to 115.7 (IQR 93.5-127.9) (P-value = 0.012). TSI (%) remained stable throughout, 71.4 (IQR 67.5-72.9) at baseline vs. 71.0 (IQR 68.2-73.0) at TLOC (P-value = 0.484).

CONCLUSIONS

NIRS provides a non-invasive surrogate of cerebral perfusion during HUT. We propose HUT incorporating NIRS monitoring in the diagnostic algorithm for patients with suspected PPS.

Syncope in a Child with Pulmonary Hypertension and Positive Gene Tests for Hereditary Hemorrhagic Telangiectasia and Long QT Syndrome

We present a 10-year-old boy with syncope who was found to have long-QT syndrome and severe Pulmonary Hypertension (PH) both in the absence of a secondary cause; to our knowledge, this is the first report with this unusual coexistence. His genetic tests were positive for hereditary hemorrhagic telangiectasia and Long QT Syndrome (LQTS) without any family history of PH or LQTS. We demonstrated that digital subtraction pulmonary angiography was more useful compared to CT angiogram to demonstrate pulmonary vascular changes which correlated with a noresponse to acute vasoreactivity testing during right heart catheterization. He has been stable for the last 2 years on Ambrisentan, Sildenafil, and Nadolol without recurrence of symptoms.

Exercise-induced Atrioventricular Block with Coronary Artery Stenosis that Appeared Five Years after Bypass Surgery

A 68-year-old man with a history of coronary artery bypass surgery was referred to our hospital because of pre-syncope on effort. During a treadmill exercise electrocardiogram test, the patient developed advanced atrioventricular block associated with dizziness. Coronary angiography revealed significant stenosis of the right coronary artery, which had not existed at the time of the bypass surgery. We implanted drug-eluting stents in the stenotic lesion, and an exercise test showed resolution of the atrioventricular block. Exercise-induced atrioventricular block is rare, and it is necessary to distinguish it from ischemic heart disease, especially in patients with a history of coronary artery disease.

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 device interrogation in the evaluation of syncope in an elderly population

BACKGROUND

Device interrogation has become a standard part of the syncope evaluation for patients admitted with permanent pacemakers (PPM) or implantable cardiac defibrillators (ICD), although few studies have shown interrogation yields clinically useful data. The purpose of this study is to determine the diagnostic yield of device interrogation as well as other commonly performed tests in the workup of unexplained syncope in patients with previously implanted PPMs or ICDs.

METHODS

We retrospectively reviewed records of 88 patients admitted to our medical center for syncope with previously implanted pacemakers between January 1, 2005 and January 1, 2015 using ICD-9 billing data.

RESULTS

Pacemaker interrogation demonstrated an arrhythmia as the cause for syncope in 4 patients (4%) and evidence of device failure secondary to perforation in 1 patient (1%). The cause of syncope was unknown in 34 patients (39%). Orthostatic hypotension was the most commonly identified cause of syncope (26%), followed by vasovagal syncope (13%), autonomic dysfunction (5%), ventricular arrhythmia (3%), atrial arrhythmia (2%), congestive heart failure (2%), stroke (2%), and other less common causes (8%). History was the most important determinant of syncope (36%), followed by orthostatic vital signs (14%), device interrogations (4%), head CT (2%), and transthoracic echocardiogram (1%).

CONCLUSIONS

Device interrogation is rarely useful for elucidating a cause of syncope without concerning physical exam, telemetry, or EKG findings. Interrogation may occasionally yield paroxysmal arrhythmias responsible for syncopal episode, but these rarely alter clinical outcomes. Interrogation appears to be more useful in patients with syncope after recent device placement.

A case report of painless type A aortic dissection with intermittent convulsive syncope as initial presentation

RATIONALE

The initial presenting symptoms and signs of acute aortic dissection are so diverse that it makes early and accurate diagnosis arduous. Painless and convulsive syncope due to cardiac arrhythmia were not typical presentations of acute aortic dissection.

PATIENT CONCERNS

A 61-year-old male presenting with transient consciousness loss and suspected seizure attack was sent to emergency room (ER) by ambulance. Consciousness loss accompanying with upward gaze and limb convulsion was noted in ER, and electrocardiogram monitor recorded a transient cardiac asystole then spontaneous recovery of sinus rhythm.

DIAGNOSES

Chest X-ray revealed widening of the mediastinum. Subsequently, contrast-enhanced chest computed tomography demonstrated Stanford type A aortic dissection.

LESSONS

To the authors' knowledge, this is the first reported case that cardiac asystole may be related to painless type A aortic dissection and then leading to convulsive syncope as presenting symptoms.

Importance of arterial distensibility in patients with vasovagal syncope

OBJECTIVE

Vasovagal syncope (VS) has a significant place in the etiology of syncope; tilt table (TT) test is used for identification of patients with vasovagal syncope (VS); however, the repeatability of the TT test is low. Upon repeated administration of TT test to patients with a positive result, the test may reveal a negative result. This feature of the test renders it inadequate particularly in evaluating therapeutical efficacy in patients receiving treatment. The left ventricular (LV) volume changes are important in the pathology of VS; in addition, LV volume changes are directly affected by the changes in the arterial system and therefore, the present study investigated arterial distensibility (AD) in this patient population.

PATIENTS AND METHODS

A total of 142 VS patients with a positive TT test result (A group) and 93 healthy individuals (B group) were enrolled in the study. The patients received tilt training treatment for 6 months. VS patients were further classified into two: syncope (+) or syncope (-) subgroup according to having at least one or more syncope episode during the 6 months of training program. All patients and controls underwent Doppler echocardiography and AD measurement which were repeated at the end of 6th month in syncope (+) and (-) subgroups.

RESULTS

The mean AD value of patients in group A was significantly lower than that of participants in group B (0.39 ± 0.1 vs. 0.42 ± 0.1, p = 0.025). In Group A, AD was significantly correlated with left ventricular diastolic filling time (DFT), isovolumetric relaxation time and right ventricular DFT (r = 0.38, p < 0.05; r = -0.42, p < 0.05; r = 0.35, p < 0.05, respectively). Syncope (+) subgroup had lower mean AD value compared to syncope (-) subgroup (0.38 ± 0.1 vs. 0.44 ± 0.1, p < 0.001).

CONCLUSIONS

AD may have valuable contribution to understanding the pathophysiology underlying VS and AD may be used in evaluating therapeutical efficacy for vasovagal syncope.

Diagnostic utility of carotid artery duplex ultrasonography in the evaluation of syncope: a good test ordered for the wrong reason

AIMS

Syncope refers to a transient loss of consciousness and postural tone secondary to cerebral hypoperfusion. Guidelines recommend against neurovascular testing in cases of syncope without neurologic symptoms; however, many pursue carotid artery duplex ultrasonography (CUS) due to the prognostic implications of identified cerebrovascular disease. Our objective was to determine the diagnostic utility of CUS in the evaluation of syncope and the identification of new or severe atherosclerosis with the potential to change patient management.

METHODS AND RESULTS

We reviewed records of 569 patients with CUS ordered for the primary indication of syncope through an accredited vascular laboratory at an academic, urban medical centre. Findings on CUS, patient demographic, clinical and laboratory information, and medications within 6 months of the CUS exam were reviewed. Bivariate relationships between key medical history characteristics and atherosclerosis status (known vs. new disease) were examined. Among 495 patients with complete information, cerebrovascular findings could potentially explain syncope in 2% (10 patients). Optimization of cardiovascular risk factors would benefit patients with known (56.6%) and new atherosclerosis (33.5%) with suboptimal lipid control, (LDL > 70 in 42.2 and 34.9% respectively; LDL > 100 in 15.7 and 20.4%), and those not on high-intensity statin therapy (80 and 87.5%) or antiplatelet medications (13.2 and 50.6%).

CONCLUSION

CUS is a low-yield diagnostic test in the evaluation of syncope, but it is useful in the diagnosis of atherosclerosis and identification of subjects who would benefit from optimal medical therapy.

[Signification of NT-proBNP in the differential diagnosis of syncope in adults]

Syncope is a transient loss of consciousness, which is the result of global brain hypoperfusion, characterized by rapid onset, short duration, and spontaneous complete resolution. Syncope is a common clinical problem due to its complex, multi-causal etiology, not completely understood pathogenesis and potential complications. Diagnosis of syncope is often associated with the implementation of many medical tests. In the recent years, the role of determining the concentration of NT-proBNP in the differential diagnosis of syncope has been highlighted. Aims of the study was analysis of NT-proBNP concentrations in patients with cardiogenic syncope in comparison to patients with neurogenic syncope and determination of the threshold value of NT-proBNP to differentiate cardiac and neurogenic syncope and to determine its sensitivity and specificity. The study included 160 pts (64 man, 96 women), aged 18 - 77 yrs (mean age 50,6) with a reflex syncope (group I) or cardiac syncope (group II). To determine the etiology of syncope, collected were: medical history for symptoms and circumstances of the syncope, measurements of blood pressure, resting ECG recording, cardiac echocardiography, and the concentration of NT-proBNP levels. Results: the group I included 80 pts (29 men, 51 women), aged 18 - 72 yrs (mean age 41.2). Group II included 80 pts (35 man, 45 women), aged 38 - 77 yrs (mean age 62.1). The assessment of concentrations of NT-proBNP showed significantly higher levels in group II than group I (467.6 +/- 227.4 vs 64.1 +/- 59.1; p <0.0001). In patients with arrhythmias and conduction abnormalities, the levels of NT-proBNP were higher in comparison to those without such disorders (364 +/- 249 vs. 171 +/- 209 pg/ml, p < 0.001). It was found that the concentration of NT-proBNP at 230.6 pg/ml might be a cut-off point that allows the prediction of cardiogenic cause of syncope with 96% specificity, 92% sensitivity and 93% negative predictive value. Conclusions: 1. The concentration of peptide NT-proBNP patients with reflex syncope. 2. It was shown that the cut off concentration of the NT-proBNP equal 230.6 pg/ml is characterized by the high sensitivity, specificity, and negative predictive value in determining the etiology of syncope.

Percutaneous atrial septostomy with modified butterfly stent and intracardiac echocardiographic guidance in a patient with syncope and refractory pulmonary arterial hypertension

PURPOSE

Syncope is associated with poor prognosis in patients with pulmonary hypertension. Atrial septostomy improves cardiac index and functional class in appropriately selected patients with pulmonary hypertension, and has been shown to improve syncope. One of the major challenges to its effectiveness is maintaining septostomy patency. We report the case of percutaneous deployment of a modified peripheral stent to create an atrial septostomy in a man with severe pulmonary hypertension and syncope, initially intolerant of medical therapy.

PROCEDURES

Percutaneous butterfly stent deployment across the interatrial septum using intracardiac echocardiography and fluoroscopy.

FINDINGS

The patient improved in all clinical parameters (BNP, six-minute walk test, dyspnoea score), and was subsequently able to tolerate targeted pulmonary hypertension therapies.

PRINCIPAL CONCLUSIONS

Atrial septostomy using butterfly stents to maintain patency may play a role in the treatment of patients with advanced pulmonary hypertension who do not respond to targeted therapy.

Vasomotor reactivity as a predictor for syncope in patients with orthostatism

OBJECTIVES

Syncope in patients with orthostatic hypotension (OH) may be the result of impaired cerebral autoregulation. Cerebral autoregulation status can be determined by assessing cerebral vasomotor reactivity (VMR). We assessed and compared VMR in patients with OH with and without syncope.

MATERIAL AND METHODS

Twenty-nine patients with OH underwent transcranial Doppler (TCD) and the Diamox test (1 g acetazolamide IV) for assessing VMR during elaboration of their OH syndrome. The percent difference between cerebral blood flow velocities (BFV) in the middle cerebral (MCA) and vertebral (VA) arteries before and after acetazolamide was defined as VMR%. We considered increases of BFV of ≥ 40% as being indicative of good VMR and classified our study patients as having good or impaired VMRs accordingly.

RESULTS

Mean VMR% values of the MCA and VA in patients with OH with syncope (n = 12) were significantly lower as compared with patients with OH without syncope (n = 17): 25.2 ± 20.5% and 42.5 ± 18.6%; 20.9 ± 15.5% and 40.8 ± 28.5%, respectively (P < 0.05).

CONCLUSIONS

Among patients with OH, we found an association between the presence of syncope and impaired VMR. Assessment of VMR among patients with OH may predict those who are at higher risk to faint and fall and to support more aggressive intervention.

Brain computed tomography in patients with syncope

OBJECTIVE

To determine the use of brain CT as a routine diagnostic tool in patients presenting with syncope.

METHODS

From March 2006 to April 2008, 292 patients presented with a history of transient loss of consciousness to the emergency department at the King Hussein Medical Center, Amman, Jordan. A neurologist examined all investigated patients and brain scans were obtained. Patients were classified into 4 groups according to brain scan findings and their neurological examination.

RESULTS

Out of the 292 patients, 254 (86.9%) patients underwent brain scan, 38 (13%) patients were excluded. The first group included 203 (79.9%) patients, who had normal brain scan, and normal neurological examination. The second group included 10 (3.9%) patients all of which had abnormal brain CT scan findings related to their syncope, and also had abnormal neurological examination. The abnormal neurological findings can be attributed to their syncopal episode and abnormal brain CT findings. Classified into 3 groups based on their brain CT findings and their neurological examination on presentation. The third group included 39 (15.3%) patients who had abnormal brain scan with findings not related to their syncope and either normal or abnormal neurological examination not related and cannot be attributed to the abnormal head CT findings and their syncopal episode. The last group had 2 patients (0.7%) with abnormal scan and normal neurological examination.

CONCLUSION

The use of brain scan as a routine diagnostic tool in patients with syncope is unjustifiable, unless there is an indication in the history or physical examination.

[Evaluation of "complex syncope: what are the indications for second-level investigations?]

Syncope is a common symptom accounting for 1.1% of all admissions to the emergency department in Italy. Diagnostic and therapeutic management of patients with syncope may be complex and with a major impact on health expenditure. A standardized approach to syncope may reduce diagnostic tests, hospitalizations and health costs. After the initial "gold standard" evaluation, which includes history, physical examination, orthostatic hypotension test and ECG, several diagnostic pathways can be followed. It has been shown that a correct initial evaluation and a thorough knowledge of syncope can reduce needless testing and increase diagnostic yield, optimizing resource management. In this review we aim to underscore the key points of the management of patients with syncope and the main indications for specific second-level examinations, such as those for neuroautonomic evaluation (tilt table test, carotid sinus massage) and implantable loop recorder. The role of Syncope Units in the management of patients with temporary loss of consciousness is also described.

Syncope from dynamic left ventricular outflow tract obstruction simulating hypertrophic cardiomyopathy in a patient with primary AL-type amyloid heart disease

Dynamic left ventricular outflow tract (LVOT) obstruction is seen classically in hypertrophic cardiomyopathy. Cardiac amyloidosis can present with asymmetric hypertrophy that resembles hypertrophic cardiomyopathy, and, in some cases, with dynamic LVOT obstruction. The occurrence of syncope in such patients is not uncommon. The syncope is usually thought to be related to mechanisms other than LVOT obstruction, such as arrhythmias, conduction disturbances, orthostatic hypotension, or vasovagal effects associated with neuropathy.Herein, we report the case of a patient who had immunocyte-derived (primary AL-type) cardiac amyloidosis with the echocardiographic appearance of hypertrophic cardiomyopathy and evidence of LVOT obstruction that caused syncope. We were able to provoke and identify dynamic LVOT obstruction that produced presyncopal symptoms similar to those that typically occur in such patients spontaneously. Dynamic LVOT obstruction as a cause of syncope should be considered in patients who have cardiac amyloidosis and echocardiographic evidence of hypertrophic cardiomyopathy.

Echocardiographic findings in a contemporary Afro-Caribbean Population referred for evaluation of unexplained syncope

Echocardiographic findings were reviewed for 106 patients (mean age 41.3 +/- 23.0 years, range 3 to 90 years, 61% female) referred for evaluation of unexplained syncope. Abnormal echocardiographic findings were seen in 36/106 (34%) patients, of which 12/106 (11%) may have an abnormality that contributed to symptoms. Abnormal echocardiographic findings (64 vs 6%, p < 0.01) and those possibly causing syncope (22 vs 0%, p < 0.05) were significantly more likely in the oldest tercile of patients compared with the youngest. No patient less than 35 years old had a possibly diagnostic abnormality.

Intracavitary pressure wire and intravascular ultrasound for the evaluation of combined symmetric hypertrophic cardiomyopathy and aortic stenosis in a patient with dyspnea and syncope: treatment with ethanol septal ablation

Among the aging population, hypertrophic cardiomyopathy and aortic stenosis often coexist. Distinguishing the contributions of these two pathologies to the patient's symptoms of congestive heart failure, chest pain and syncope is often challenging. Furthermore, the appropriate treatment is highly dependent on a clear determination of pathophysiology. Here, we present a novel application of quantitative pressure-wire measurements and qualitative intravascular ultrasound assessment of the left ventricular outflow tract and aortic valve in determining the contributions of aortic stenosis and symmetric hypertrophic cardiomyopathy to the overall left ventricular-aortic gradient. After establishing that the majority of outflow obstruction was dynamic and related to the hypertrophic cardiomyopathy, the patient underwent successful ethanol septal ablation.

Can echocardiographic findings predict falls in older persons?

Background

The European and American guidelines state the need for echocardiography in patients with syncope. 50% of older adults with syncope present with a fall. Nonetheless, up to now no data have been published addressing echocardiographic abnormalities in older fallers.

Method and Findings

In order to determine the association between echocardiographic abnormalities and falls in older adults, we performed a prospective cohort study, in which 215 new consecutive referrals (age 77.4, SD 6.0) of a geriatric outpatient clinic of a Dutch university hospital were included. During the previous year, 139 had experienced a fall. At baseline, all patients underwent routine two-dimensional and Doppler echocardiography. Falls were recorded during a three-month follow-up. Multivariate adjustment for confounders was performed with a Cox proportional hazards model. 55 patients (26%) fell at least once during follow-up. The adjusted hazard ratio of a fall during follow-up was 1.35 (95% CI, 1.08–1.71) for pulmonary hypertension, 1.66 (95% CI, 1.01 to 2.89) for mitral regurgitation, 2.41 (95% CI, 1.32 to 4.37) for tricuspid regurgitation and 1.76 (95% CI, 1.03 to 3.01) for pulmonary regurgitation. For aortic regurgitation the risk of a fall was also increased, but non-significantly (hazard ratio, 1.57 [95% CI, 0.85 to 2.92]). Trend analysis of the severity of the different regurgitations showed a significant relationship for mitral, tricuspid and pulmonary valve regurgitation and pulmonary hypertension.

Conclusions

Echo(Doppler)cardiography can be useful in order to identify risk indicators for falling. Presence of pulmonary hypertension or regurgitation of mitral, tricuspid or pulmonary valves was associated with a higher fall risk. Our study indicates that the diagnostic work-up for falls in older adults might be improved by adding an echo(Doppler)cardiogram in selected groups.

Arterial and venous response to Tilt with LBNP test after a 60 day HDT bedrest (WISE study)

The objective was to quantify the Cerebral, and Femoral arterial hemodynamics as well as the calf vein section changes induced by a Tilt up test continuing with a Tilt plus LBNP after a 60 day HDT (WISE).

METHOD

24 healthy volunteers (25-40 y) underwent a 60 day HDT (-6 degree) bedrest: 8 as Control (Co), 8 with Exercise (Ex: treadmill under LBNP and flywheel), 8 with Nutrition (Nut: daily protein supplement). At R+0 all of them underwent a 10 min 80 degree Tilt up test, to which several LBNP period of 3 min were added (from -10 to -50 mmHg by steps of 10 mmHg) until presyncopal stage. Cerebral and Femoral flow changes were assessed by Doppler. Posterior Tibial, and Gastrocnemian vein were investigated by echography.

RESULTS

At Post HDT 10 min Tilt: cerebral flow decreased similarly in the 3 groups, but more in the non finishers than in the finishers, while the femoral decreased similarly in all groups. Leg vascular resistance and cerebral/femoral flow ratio increased less in the Co and Nut gr than in the Ex gr, and also in the non finishers than in the finishers. Percent increase in Gastrocnemian and Tibial section was higher in Co and Nut gr than in Ex gr, and in non finishers than in finishers.

CONCLUSION

Non exercise and non finisher subjects showed a lack of leg vasoconstriction, and a higher calf vein distensibility at post HDT Tilt test.

Safety of and tolerance to adenosine infusion for myocardial perfusion single-photon emission computed tomography in a Japanese population

BACKGROUND

Adenosine has been available for use in myocardial perfusion single-photon emission computed tomography (SPECT) in Japan since 2005. The purpose of this study was to evaluate the safety of and tolerance to thallium-201 myocardial perfusion SPECT with intravenous adenosine infusion in Japanese patients with suspected coronary artery disease.

METHODS AND RESULTS

Two hundred and six consecutive patients who underwent an adenosine infusion (120 mug . kg(-1) . min(-1)) SPECT at Sumitomo Besshi Hospital (Niihama, Japan) were investigated. The effects of adenosine infusion were monitored for each patient. A coronary angiography was performed in 81 patients. Adenosine infusion significantly decreased blood pressure and increased heart rate. Adverse reactions were observed in 161 patients (78.2%). Most reactions were transient, disappearing soon after the termination of adenosine infusion. No serious adverse reactions, such as acute myocardial infarction or death, occurred. Adenosine infusion was terminated in 3 patients (1.5%) because of near syncope or sustained 2:1 atrioventricular block. Electrocardiographic changes occurred in 15 patients (7.3%). Self-assessed scoring after SPECT showed that the patients were very tolerant (74.6% of 177 patients) of adenosine infusion myocardial SPECT. The sensitivity and specificity were 75.0% and 69.7%, respectively.

CONCLUSIONS

Adenosine infusion myocardial SPECT is safe and well tolerated in the Japanese population, despite the frequent occurrence of minor adverse reactions.

The yield of head CT in syncope: a pilot study

Although head CT is often routinely performed in emergency department (ED) patients with syncope, few studies have assessed its value.

OBJECTIVES

To determine the yield of routine head CT in ED patients with syncope and analyse the factors associated with a positive CT.

METHODS

Prospective, observational, cohort study of consecutive patients presenting with syncope to an urban tertiary-care ED (48,000 annual visits).

INCLUSION CRITERIA

age >or=18 and loss of consciousness (LOC). Exclusion criteria included persistent altered mental status, drug-related or post-trauma LOC, seizure or hypoglycaemia. Primary outcome was abnormal head CT including subarachnoid, subdural or parenchymal haemorrhage, infarction, signs of acute stroke and newly diagnosed brain mass.

RESULTS

Of 293 eligible patients, 113 (39%) underwent head CT and comprise the study cohort. Ninety-five patients (84%) were admitted to the hospital. Five patients, 5% (95% CI=0.8%-8%), had an abnormal head CT: 2 subarachnoid haemorrhage, 2 cerebral haemorrhage and 1 stroke. Post hoc examination of patients with an abnormal head CT revealed focal neurologic findings in 2 and a new headache in 1. The remaining 2 patients had no new neurologic findings but physical findings of trauma (head lacerations with periorbital ecchymoses suggestive of orbital fractures). All patients with positive findings on CT were >65 years of age. Of the 108 remaining patients who had head CT, 45 (32%-51%) had signs or symptoms of neurologic disease including headache, trauma above the clavicles or took coumadin. Limiting head CT to this population would potentially reduce scans by 56% (47%-65%). If age >60 were an additional criteria, scans would be reduced by 24% (16%-32%). Of the patients who did not have head CT, none were found to have new neurologic disease during hospitalisation or 30-day follow-up.

CONCLUSIONS

Our data suggest that the derivation of a prospectively derived decision rule has the potential to decrease the routine use of head CT in patients presenting to the ED with syncope.

Association of takotsubo cardiomyopathy and long QT syndrome

A young woman presented with takotsubo cardiomyopathy after a syncopal attack caused by torsades de pointes. Two-dimensional echocardiography on admission showed left ventricular apical akinesis (ballooning) and basal hyperkinesis, compatible with takotsubo cardiomyopathy. This gradually normalized in 2 months. ECG on admission showed remarkable QT prolongation, U waves, and negative T waves, which also gradually normalized. Coronary angiography revealed no organic stenosis; however, acetylcholine provocation test caused the QT interval to again become prolonged. During treadmill exercise stress testing, the QT interval shortened as heart rate increased. Therefore, without genetic analysis, this patient was considered to have sporadic long QT syndrome in which takotsubo cardiomyopathy developed after the syncopal attack caused by torsades de pointes.

Syncope

Syncope is defined as an acute, brief and transient loss of consciousness and postural tone with spontaneous and complete recovery. Neurovascular ultrasound has contributed to elucidate the underlying mechanism of different types of syncope. In routine diagnostic work-up of patients with syncope, however, neurovascular ultrasound is not among the first line tools. In particular, an ultrasound search for occlusive cerebro-vascular disease is of limited value because cerebral artery obstruction is a very rare and questionable cause of syncope. Transcranial Doppler sonography monitoring of the cerebral arteries is useful in the diagnostic work-up of patients with suspicion of postural related, cerebrovascular, cough and psychogenic syncope, and in some cases for differentiating focal epileptic seizures from transient ischemic attacks and migraine with aura.

The utility of head computed tomography in the emergency department evaluation of syncope

OBJECTIVE

Current guidelines for evaluation of syncope recommend that in the absence of objective focal neurologic findings, head computed tomography (HCT) may not be necessary. Compliance with this recommendation is highly variable, which may be due in part to the lack of currently available evidence. We undertook the following investigation to determine whether HCT aids in the diagnostic investigation of syncope.

METHODS

This study was a retrospective chart review of all adult patients who presented to an urban emergency department, and who had a HCT ordered for syncope, during a 6-month period in 2001. Patients with competing indications for HCT, or those with a presentation consistent with seizures were excluded. Charts were assigned to the "positive" or "negative" HCT group depending on whether the treating physician considered HCT findings relevant to the syncopal event.

RESULTS

A total of 202 patients had a HCT performed for syncope. Eighty-five patients met one or more of the exclusion criteria. HCT of the remaining 117 patients were analyzed. None of the 117 patients had a HCT finding that was clinically related to the syncopal event.

CONCLUSIONS

HCT yielded no relevant clinical findings in our entire sample of patients with syncope. Our findings combined with previous studies add to the growing body of evidence that HCT for syncope in the absence of focal neurologic findings may not be necessary.