Wishwa N. Kapoor
University of Pittsburgh
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The New England Journal of Medicine | 1983
Wishwa N. Kapoor; Michael Karpf; Sam Wieand; Jacqueline Peterson; Gerald S. Levey
We prospectively evaluated and followed 204 patients with syncope to determine how often a cause of syncope could be established and to define the prognosis of such patients. A cardiovascular cause was established in 53 patients and a noncardiovascular cause in 54. The cause remained unknown in 97 patients. At 12 months, the overall mortality was 14 +/- 2.5 per cent. The mortality rate (30 +/- 6.7 per cent) in patients with a cardiovascular cause of syncope was significantly higher than the rate (12 +/- 4.4 per cent) in patients with a noncardiovascular cause (P = 0.02) and the rate (6.4 +/- 2.8 per cent) in patients with syncope of unknown origin (P less than 0.0001). The incidence of sudden death was 24 +/- 6.6 per cent in patients with a cardiovascular cause, as compared with 4 +/- 2.7 per cent in patients with a noncardiovascular cause (P = 0.005) and 3 +/- 1.8 per cent in patients with syncope of unknown origin (P = 0.0002). Patients with syncope can be separated into diagnostic categories that have prognostic importance. Patients with a cardiovascular cause have a strikingly higher incidence of sudden death than patients with a noncardiovascular or unknown cause.
Angiology | 1987
Michael J. Fine; Wishwa N. Kapoor; Vincent Falanga
Cholesterol crystal embolization (CCE) frequently presents with nonspecific manifestations that mimic other systemic diseases. The authors reviewed 221 cases of histologically proven CCE in the English literature to define the clinical, laboratory, and pathologic characteristics of this disorder. CCE affected predominantly elderly males (mean age sixty-six) with a frequent history of hypertension (61%), atherosclerotic cardiovascular disease (44%), renal failure (34%), and aortic aneurysms (25%) at presentation. At least one possible predisposing factor was present in 31 % and included operative and radiological vascular procedures and the use of anticoagulants. Cutaneous findings (34%) and renal failure (50%) were two of the most common clinical findings throughout the course of CCE. The nonspecific signs and symptoms included: fever (7%), weight loss (7%), myalgias (4%), and headache (3%). Premortem diagnoses were established in 31 % of patients most commonly by biopsy of the muscle, skin, and kidney. Mortality was high (81 %) and was most commonly due to multifactorial, cardiac, and renal etiologies. The authors conclude that CCE should be strongly considered in elderly patients with atherosclerotic vascular disease who have the onset of renal insufficiency and cutaneous manifestations. CCE may be confirmed by a skin or muscle biopsy.
Journal of the American Geriatrics Society | 1992
Joseph Francis; Wishwa N. Kapoor
To determine survival, functional independence, and cognitive performance of older patients 2 years after an episode of delirium.
Annals of Internal Medicine | 1997
Mark Linzer; N.A. Mark Estes; Paul J. Wang; Vicken R. Vorperian; Wishwa N. Kapoor
Syncope is a transient loss of consciousness that is accompanied by loss of postural tone. It is common [1] and can be dangerous [2], disabling [3], and difficult to diagnose [4]. Thousands of dollars can be spent evaluating a patient with syncope, only to result in a series of negative test results and a patient who continues to faint. Because the range of prognoses in syncope is wide, the physicians principal initial task is to distinguish between benign and life-threatening causes of syncope. We intend primarily to help clinicians maximize the diagnostic yield in the workup of syncope. Our secondary purpose is to summarize the literature that will aid clinicians in assessing risk to enable them to target hospitalization and invasive testing for the patient with syncope who is at high risk for an adverse outcome. The questions addressed by this two-part study are 1) Which diagnostic techniques are the most valuable for patients with syncope? 2) How can the clinical history help focus the workup for patients with syncope? and 3) When should patients with syncope be hospitalized? Methods We used the MEDLINE database to identify articles related to syncope and diagnostic testing. References that evaluated the diagnostic test in near syncope and dizziness were included if they also used the test in patients with syncope. When a medical subject heading did not identify a sufficient number of references about a particular diagnostic test (such as neurovascular testing or carotid Doppler ultrasonography), keyword searches (using such terms as transcranial Doppler) were done. To be included in the review, articles had to be published in the English language between 1980 and 1995. The studies had to be randomized trials, observational studies, cohort studies, or case series of more than 10 patients (review articles and case reports were excluded); had to focus on or include patients with syncope; and had to examine only patients 18 years of age or older (except for tilt-table studies, which often included adult and pediatric cases in the same articles). Articles that were candidates for review were evaluated in detail by one of the authors. Articles that met the selection criteria were used to prepare summary tables or paragraphs. Comparisons between groups (for example, the proportion of patients with and without heart disease who had tachyarrhythmias diagnosed by electrophysiologic testing) were made using the Fisher exact test. Selected national experts in cardiology and neurology were asked to review the findings in their area of expertise. The opinions of these experts were incorporated into the recommendations. Limitations of the Literature on Syncope In syncope, there is no diagnostic gold standard against which other diagnostic tests may be measured; thus, sensitivity and specificity may not be easily calculated. Moreover, the presence of a disease, such as coronary disease, in a patient who has fainted does not prove that the disease caused the syncope. Syncope is, at its core, a symptom and not a disease. Therefore, this review is not organized around a technology or a disease entity but focuses on the physiologic states that lead to a sudden, transient loss of consciousness. The literature that discusses syncope predominantly comprises case series or cohort studies based on referrals to tertiary care centers. We classified studies into three types: population-based studies (including unselected patients from the general population who were hospitalized or seen in emergency departments and other outpatient settings), referral-based studies (including patients referred to specialized centers for syncope workups), and small case series. To our knowledge, no randomized trials of the diagnostic workup or management strategies for patients with syncope have been done. A summary of the types of studies conducted in patients with syncope (Table 1) shows that most have been referral studies or case series. Table 1. Sample Characteristics of Studies of Diagnostic Tests and Syncope Definitions Organic Heart Disease Whenever possible, our definition of organic heart disease included coronary artery disease, congestive heart failure, valvular heart disease, cardiomyopathy, and congenital heart disease. Because conduction system disease is a separate predictor of the need for special diagnostic testing, it was kept apart except where indicated. Patients who had a history and physical examination that were negative for cardiovascular symptoms or signs and a normal electrocardiogram were considered to have normal hearts; however, we recognize that some investigators think that echocardiography should be done before patients are declared free of organic heart disease. Diagnostic Yield For most tests, the diagnostic yield reflects the number of patients with positive diagnostic test results divided by the number of tested patients. For Holter and loop monitoring, the numerator includes the sum of the true-positive test results (arrhythmias during fainting) plus the true-negative test results (normal rhythm during symptoms). This expanded definition reflects the prognostic importance of a negative result on electrocardiography during syncope. For certain tests, the absolute value of the diagnostic yield may not be as important as the ability of the test to exclude a serious diagnosis (for example, intracardiac electrophysiologic studies may be of considerable benefit when they exclude ventricular tachycardia in a patient in whom that diagnosis was strongly considered). Data Synthesis Differential Diagnosis The first category of syncope is neurally mediated syncope, which results from reflex mechanisms that are associated with inappropriate vasodilatation, bradycardia, or both (Table 2). This category includes vasovagal, vasodepressor, situational, and carotid sinus syncope. Neurocardiogenic mechanisms are also implicated in syncope associated with ventricular outflow obstruction (such as with aortic stenosis and pulmonary embolism) as well as supraventricular tachyarrhythmias [5-9]. The second category is orthostatic hypotension, which may result from age-related physiologic changes, volume depletion, medication, and autonomic insufficiency [10, 11]. Psychiatric disorders related to syncope (such as anxiety, depression, and conversion disorders) form a third category. The fourth category includes neurologic disorders, although these rarely cause syncope unless patients with seizures are included. Neurologic causes of syncope include transient ischemia (almost exclusively involving the vertebrobasilar territory), migraines (basilar artery), and seizures (atonic seizures, temporal lobe epilepsy, and unwitnessed grand mal seizures) [12]. Table 2. Causes of Syncope Cardiac causes of syncope include coronary disease, congenital and valvular heart disease, cardiomyopathy, arrhythmias, and conduction system disorders. Coronary disease, congestive heart failure, ventricular hypertrophy, and myocarditis may set the stage for arrhythmia and syncope. Exertional syncope results from heart disease characterized by a fixed cardiac output that does not increase with exercise. Exertional syncope may also reflect arrhythmic or neurocardiogenic disorders or an anomalous coronary artery. Syncope may be the presenting symptom in elderly patients with acute myocardial infarction [13]; it rarely occurs with coronary artery spasm and aortic dissection. We used five population-based studies of unselected patients to estimate the prevalence of various causes of syncope [14-18]; the summary of these studies is necessarily limited by the variability in diagnostic criteria. The most common causes of syncope were vasovagal episode, heart disease and arrhythmias, orthostatic hypotension, and seizures. The cause of syncope could not be determined in approximately 34% of patients. All of these studies were done several years ago, and the proportion of patients with unexplained syncope is probably lower now, given wider use of event monitoring, tilt testing, electrophysiologic studies, attention to psychiatric illnesses, and recognition that the cause of syncope in elderly patients may be multifactorial. Approach to Syncope The algorithm depicted in Figure 1 provides a diagnostic approach to syncope. It is intended to provide a framework for clinical judgment, not to replace it. Key points in the algorithm that will be discussed in the text include the following. Figure 1. Algorithm for diagnosing syncope. 1. History, physical examination, and electrocardiography are the core of the workup for patients with syncope. 2. Carotid sinus massage may be useful in elderly patients but should not be done by the generalist if bruits are present, if the patient has a history of ventricular tachycardia, or in the setting of a recent stroke or myocardial infarction. A false-positive test result should be suspected if carotid massage is positive but the history does not suggest carotid hypersensitivity. 3. Special issues for elderly patients include the multifactorial nature of syncope, polypharmacy, use of carotid sinus massage, and cardiac testing (exercise stress test and echocardiography) to exclude cardiac disease. 4. Nondiagnostic arrhythmias found on Holter monitor readings should not usually be treated. 5. Intracardiac electrophysiologic studies are most useful in patients who have organic heart disease and otherwise unexplained syncope. 6. In a patient with exertional syncope, echocardiography should precede exercise stress testing. 7. The assessment of patients with a normal heart who have frequent episodes of syncope should include a loop recorder and psychiatric evaluation. 8. The workup of patients with a normal heart who have infrequent episodes of syncope should include a tilt test and psychiatric evaluation. 9. Neurologic testing, including electroencephalography, computed tomography, and carotid and transcranial Doppler ultrasonography, should be resePURPOSE To review the literature on diagnostic testing in syncope and provide recommendations for a comprehensive, cost-effective approach to establishing its cause. DATA SOURCES Studies were identified through a MEDLINE search (1980 to present) and a manual review of bibliographies of identified articles. STUDY SELECTION Papers were eligible if they addressed diagnostic testing in syncope or near syncope and reported results for at least 10 patients. DATA EXTRACTION The usefulness of tests was assessed by calculating diagnostic yield: the number of patients with diagnostically positive test results divided by the number of patients tested or, in the case of monitoring studies, the sum of true-positive and true-negative test results divided by the number of patients tested. DATA SYNTHESIS Despite the absence of a diagnostic gold standard and the paucity of data from randomized trials, several points emerge. First, history, physical examination, and electrocardiography are the core of the syncope workup (combined diagnostic yield, 50%). Second, neurologic testing is rarely helpful unless additional neurologic signs or symptoms are present (diagnostic yield of electroencephalography, computed tomography, and Doppler ultrasonography, 2% to 6%). Third, patients in whom heart disease is known or suspected or those with exertional syncope are at higher risk for adverse outcomes and should have cardiac testing, including echocardiography, stress testing. Holter monitoring, or intracardiac electrophysiologic studies, alone or in combination (diagnostic yields, 5% to 35%). Fourth, syncope in the elderly often results from polypharmacy and abnormal physiologic responses to daily events. Fifth, long-term loop electrocardiography (diagnostic yield, 25% to 35%) and tilt testing (diagnostic yield < or = 60%) are most useful in patients with recurrent syncope in whom heart disease is not suspected. Sixth, psychiatric evaluation can detect mental disorders associated with syncope in up to 25% of cases. Seventh, hospitalization may be indicated for patients at high risk for cardiac syncope (those with an abnormal electrocardiogram, organic heart disease, chest pain, history of arrhythmia, age > 70 years) or with acute neurologic signs. CONCLUSIONS Many tests for syncope have a low diagnostic yield. A careful history, physical examination, and electrocardiography will provide a diagnosis or determine whether diagnostic testing is necessary in most patients.
The American Journal of Medicine | 1994
Wishwa N. Kapoor; Melanie A. Smith; Nancy L. Miller
BACKGROUND Upright tilt testing is widely utilized for the evaluation of syncope. Recently, there have been concerns about the specificity and the lack of standard methodology for this test. The purpose of this study was to summarize the methodologies of upright tilt testing in patients with syncope of unknown origin, the responses in control subjects, and the reproducibility and selection of therapy. METHODS We used MEDLINE to search English language articles from 1966 to June 30, 1992. Studies were included for content review if they met our inclusion criteria. Data were extracted from each article by two trained reviewers using a predesigned data collection instrument. RESULTS Thirty-three articles were included for review. There was considerable variability in the methodologies of tilt testing. Overall positive responses were reported in 49% of patients in passive-only studies as compared with 66% of patients in studies using isoproterenol with tilt testing. The percentage of positive responses increased with increasing angle of testing for studies using isoproterenol. There was no relationship between the percentage of positive responses and the maximum dose of isoproterenol. When we compared the results of passive studies that tested patients for 60 minutes at 60 degrees with the results of isoproterenol studies that tested patients at 60 degrees, the positive rate for passive-only studies was 54% as compared with 52% for the isoproterenol studies. The percentage of positive response in control subjects with passive studies was 8.9% (range 0% to 100%), and with isoproterenol 27% (range 0% to 65%). Other groups of patients showed a wide range of positive responses (range 0% to 83%). Reproducibility ranged from 71% to 87%. Upon retesting while the patient was receiving therapy, 90% of 115 positive patients were negative. Eighty-nine percent of 105 positive patients who were receiving therapy and followed for a mean time of 12 months were free of syncope. CONCLUSIONS This review strongly suggests that isoproterenol may not have an effect on stimulating vasovagal syncope during upright tilt testing. We recommend protocols of passive tilt testing procedures at 60 degrees for 45 to 60 minutes since the overall specificity is higher with this method. The use of isoproterenol during tilt testing adds to the cost and complexity of the test, is associated with a higher rate of false-positive responses, leads to potential complications, and, thus, should be avoided.
Annals of Emergency Medicine | 1997
Thomas P. Martin; Barbara H. Hanusa; Wishwa N. Kapoor
STUDY OBJECTIVE To develop and validate a risk classification system for patients presenting to emergency departments with syncope. METHODS Two prospective studies were carried out at a large urban teaching hospital ED. One cohort of 252 patients with syncope who reported to the ED was used to develop the risk classification system; a second cohort of 374 patients with syncope was used to validate the system. Data from the patients history, physical examination and ED ECG were used to identify predictors of arrhythmias or mortality within the first year. Arrhythmias were detected by cardiac monitoring or electrophysiologic studies. Logistic regression and Cox proportional hazards models were used to identify the important risk factors for the classification system. Performance of the system was measured by comparing the proportion of patients with arrhythmias or death at various levels of the risk and receiver operating characteristic curves. RESULTS Multivariate predictors of arrhythmia or 1-year mortality were an abnormal ED ECG (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.6 to 6.4); history of ventricular arrhythmia (OR, 4.8; 95% CI, 1.7 to 13.9); history of congestive heart failure (OR, 3.2; 95% Cl, 1.3 to 8.1). Arrhythmias or death within 1 year occurred in 7.3% (derivation cohort) to 4.4% (validation cohort) of patients without any risk factors and in 80.4% (derivation) to 57.6% (validation) of patients with three or four risk factors. CONCLUSION Historical and ECG factors available at the time of presentation can be used to stratify risk of arrhythmias or mortality within 1 year in ED patients presenting with syncope.
Annals of Internal Medicine | 1997
Mark Linzer; N.A. Mark Estes; Paul J. Wang; Vicken R. Vorperian; Wishwa N. Kapoor
In the first part of this two-part study [1], the differential diagnosis of syncope was examined with respect to the information provided by results of the history, physical examination, and electrocardiography; an algorithmic approach to the diagnosis of syncope was also introduced. A careful history and physical examination are mandatory in all patients with syncope because they are the keys to determining whether additional diagnostic testing is required. Electrocardiography is recommended for almost all patients with syncope, whereas specialized neurologic testing is suggested only in certain circumstances: for example, computed tomography for patients with focal neurologic signs, electroencephalography for patients with seizure activity, or carotid or transcranial Doppler ultrasonography for patients with carotid bruits or a history of neurovascular symptoms. This paper addresses the workup of patients with syncope that is unexplained by the results of history, physical examination, or surface 12-lead electrocardiography. Unexplained Syncope Syncope that remains unexplained after initial clinical assessment is of considerable concern to the practicing clinician. The algorithm that we developed provides three branches for unexplained syncope: one for patients known to have or suspected of having heart disease, one for elderly patients, and one for patients not known to have or suspected of having heart disease (Figure 1). Figure 1. Algorithm for diagnosing syncope. Branch 1: Unexplained Syncope with Clinical Organic Heart Disease or Abnormal Electrocardiogram Organic heart disease is often known, discovered, or suspected in patients who have sudden or exertional syncope. Evaluation of patients known to have or suspected of having heart disease often begins with echocardiography or an exercise stress test to determine and quantify the degree of heart disease. If the results of these tests are negative, further cardiac testing can often be avoided. If the results are positive, however, subsequent testing may include Holter monitoring or telemetry, signal-averaged electrocardiography, and intracardiac electrophysiologic studies. Echocardiography No studies have been specifically designed to assess the usefulness of echocardiography in syncope. In patients known to have or suspected of having heart disease, patients suspected of having arrhythmias, or patients with abnormal electrocardiograms, echocardiography is an important initial step in diagnostic testing. Unsuspected findings on echocardiography are reported in only 5% to 10% of unselected patients [2]. This yield is similar to that of 12-lead electrocardiography, but echocardiography is 7 times more expensive. The cost-effectiveness of echocardiography in diagnosing the cause of syncope has yet to be determined. Exercise Testing Exercise stress testing can be used for the evaluation of exertional syncope to diagnose ischemia or exercise-induced tachyarrhythmias or to reproduce exercise-associated or postexertional syncope. In one population study of patients with syncope, the yield of the exercise stress test was less than 1% [3]. No data are available to determine the yield for ischemia or exercise-induced tachyarrhythmias or to define the tests usefulness in diagnosing exercise-associated syncope. Tilt-table testing has been used to diagnose neurally mediated syncope, which may manifest as postexertional syncope [4, 5]. Exercise stress testing is recommended if patients have exercise-associated syncope and if the results of clinical evaluation suggest ischemic heart disease. In patients with exertional syncope, echocardiography should be done first to exclude hypertrophic cardiomyopathy. 24-Hour Holter Monitoring We summarize the results of ambulatory monitoring in syncope by determining the presence or absence of arrhythmias in patients who develop symptoms during monitoring [6]. In studies that evaluated syncope or presyncope with 12 or more hours of monitoring and reported on symptoms, 4% of patients had correlation of symptoms with arrhythmias (Table 1) [7-14]. In about 15% of patients, symptoms were not associated with arrhythmias; this finding excluded rhythm disturbance as a cause for syncope in these patients (overall diagnostic yield in 8 studies, 4% + 15% = 19%). No symptoms occurred in approximately 79% of patients, but arrhythmias were found in 14% [7-14]. The causal relation between most of these arrhythmias and syncope is uncertain, although certain uncommon asymptomatic arrhythmias (prolonged sinus pauses, Mobitz type II block, and sustained ventricular tachycardia during sleep) usually prompt appropriate treatment. If no arrhythmias are found and no symptoms occur during monitoring, arrhythmic syncope is not necessarily excluded; this is because of the episodic nature of arrhythmias. In patients with a high pretest likelihood of arrhythmias (for example, patients who have brief loss of consciousness with short or absent prodrome, an abnormal electrocardiogram, or organic heart disease), further evaluation for arrhythmias should be pursued by event monitoring or electrophysiologic studies. Table 1. Yield of Prolonged Electrocardiographic (Holter) Monitoring in Syncope Only one study evaluated the effect of duration of monitoring on diagnostic yield [7]. Extending monitoring to 72 hours increased the number of arrhythmias detected (14.7% on the first day, an additional 11.1% the second day, and an additional 4.2% the third day) but not the yield for arrhythmias associated with symptoms. A 24-hour Holter monitor or inpatient telemetry is recommended when symptoms suggest arrhythmic syncope (brief loss of consciousness, no prodrome, palpitations with syncope) and in patients who have syncope of unexplained cause, heart disease, or an abnormal electrocardiogram. Loop monitoring may be a reasonable alternative in patients with recurrent syncope and a normal heart. Intracardiac Electrophysiologic Studies Although they are relatively safe in patients with syncope [15], electrophysiologic studies are expensive and invasive. Such studies are associated with low risks for pulmonary embolism, cardiac perforation, arteriovenous fistulae, and myocardial infarction (cumulative risk < 3%) [16]. Electrophysiologic studies use electric stimulation and monitoring to discover conduction abnormalities that predispose patients to bradyarrhythmias and to determine a patients propensity for developing tachyarrhythmias (both ventricular and supraventricular). Most protocols for programmed stimulation include three extrastimuli at one or two ventricular sites. More aggressive protocols, including the use of isoproterenol, may increase the sensitivity but decrease the specificity of tests for detecting tachyarrhythmias. The most important outcome of electrophysiologic testing is the diagnosis of ventricular tachycardia. Other potentially important diagnostic outcomes include supraventricular tachycardias and bradyarrhythmias. Because only a few studies have used 24-hour Holter monitoring to confirm results of electrophysiologic studies [17, 18], the true diagnostic yield of this testing is generally unknown. Nevertheless, it is agreed that the results of an electrophysiologic test are considered positive if the test uncovers any of the following: 1) sustained monomorphic ventricular tachycardia [not including polymorphic ventricular tachycardia or ventricular fibrillation, which may be nonspecific responses], 2) a prolonged corrected sinus node recovery time longer than 1000 milliseconds, 3) markedly prolonged HV intervals longer than 90 milliseconds, 4) spontaneous or induced infra-Hisian block, and 5) supraventricular tachycardia with hypotension. For the accompanying analysis, we used the above definitions wherever possible, excluding supraventricular tachycardias (which are relatively uncommon outcomes of electrophysiologic testing in syncope and can be diagnosed by other means). Our primary purpose was to classify study results to determine predictors of positive results on electrophysiologic studies. Key predictors that we assessed were presence of organic heart disease and brady-arrhythmic abnormalities (such as conduction-system disease) found on 12-lead electrocardiography. Fourteen studies evaluating 1423 patients provided information on electrophysiologic outcomes but had insufficient detail to assess the importance of organic heart disease and baseline electrocardiography [19-32]. Heart disease was present in slightly more than half of the patients. Ventricular tachycardia was diagnosed in 14%, whereas a bradycardic outcome was observed in 21%. Because some patients (about 10%) had both tachycardic and bradycardic outcomes, the overall diagnostic yield in these studies (in which a high prevalence of patients had organic heart disease) was approximately 32% [14% ventricular tachycardia + 21% bradycardias 10% x (14 + 21)]. Table 2 summarizes eight additional studies in which the contribution of organic heart disease to a positive test result could be assessed [15, 17, 18, 33-37]. In these studies, 625 patients underwent electrophysiologic testing for syncope. Of the 406 patients with organic heart disease or an abnormal electrocardiogram, 21% had ventricular tachycardia and 34% had a bradycardia during the electrophysiologic study. Of the 219 patients with normal hearts, only 1% had ventricular tachycardia and 10% had a documented bradycardia (P < 0.001 for both comparisons). In these studies, approximately 14% of patients who could be given a diagnosis had both ventricular tachycardia and bradycardia. Thus, the diagnostic yield of electrophysiologic studies was almost 50% in patients with organic heart disease and about 10% in patients with a normal heart. Table 2. Diagnostic Yield of Intracardiac Electrophysiologic Studies in Syncope: Importance of Organic Heart Disease* These data are further elucidated by Table 3, which describes six referral stPURPOSE To review the literature on diagnostic testing in syncope that remains unexplained after initial clinical assessment. DATA SOURCES MEDLINE search. STUDY SELECTION Published papers were selected if they addressed diagnostic testing in syncope, near syncope, or dizziness. DATA EXTRACTION Studies were identified as population studies, referral studies, or case series. DATA SYNTHESIS After a thorough history, physical examination, and electrocardiography, the cause of syncope remains undiagnosed in 50% of patients. In such patients, information may be derived from the results of carefully selected diagnostic tests, especially 1) electrophysiologic studies in patients with organic heart disease, 2) Holter monitoring or telemetry in patients known to have or suspected of having heart disease, 3) loop monitoring in patients with frequent events and normal hearts, 4) psychiatric evaluation in patients with frequent events and no injury, and 5) tilt-table testing in patients who have infrequent events or in whom vasovagal syncope is suspected. Hospitalization is indicated for high-risk patients, especially those with known heart disease and elderly patients. CONCLUSIONS A flexible, focused approach is required to diagnose syncope. Features of the initial history and physical examination help guide diagnostic testing.
Annals of Internal Medicine | 1992
Wishwa N. Kapoor; Nancy Brant
OBJECTIVE To determine the proportion of patients with syncope of unknown etiology who have a positive response to upright tilt testing and to determine the specificity of this test as a marker for vasodepressor syncope. DESIGN Comparison of upright tilt testing with isoproterenol in patients with syncope of unknown etiology and in controls. SETTING Outpatient clinics of a tertiary care center. PATIENTS A total of 20 patients with syncope of unknown etiology and 40 controls matched by age, sex, and lack of underlying cardiovascular or other diseases had upright tilt testing with isoproterenol infusion. Controls consisted of two groups (groups I and II) who had slightly different methods of tilt testing in conjunction with isoproterenol. INTERVENTIONS Upright tilt testing at 80 degrees from horizontal was done for up to 15 minutes. If end points were not reached, infusion of isoproterenol was started at 1 microgram/min and increased with graded increments in infusion rates up to 5 micrograms/min. MEASUREMENTS The development of syncope or presyncope in association with hypotension, bradycardia, or both. MAIN RESULTS Positive response to tilt testing in patients with syncope was 75% (95% CI, 55% to 95%); it was 65% in control group I (CK, 44% to 86%) and 45% in control group II (CI, 20% to 70%). Case patients and controls with positive tilt-test responses were similar with respect to time to completion of the test, mean total isoproterenol dose, mean isoproterenol dose level at completion, average mean blood pressure at completion, mean heart rate at completion, mean decline in systolic blood pressure, and decline in mean blood pressure or heart rate (P greater than 0.05 for all comparisons). Further, symptoms during tilt testing in case patients with positive responses were similar to those in controls with positive tilt-test results. CONCLUSIONS The rate of positive tilt testing in patients with syncope is equivalent to that in controls without a history of syncope. The low specificity of this test makes its use as a marker for vasodepressor syncope questionable.
The American Journal of Medicine | 1986
Wishwa N. Kapoor; Diane Snustad; Jacqueline Peterson; Harry S. Wieand; Ruth Cha; Michael Karpf
This report describes the evaluation of syncope in 210 elderly patients as compared with 190 younger patients. The elderly group had a mean age of 71 years (range 60 to 90) and the younger group had a mean age of 39 years (range 15 to 59). A cardiovascular cause was found in 33.8 percent of the elderly and in 16.8 percent of the young (p = 0.0001), a noncardiovascular cause in 26.7 percent of the elderly and 37.9 percent of the young (p = 0.02), and unknown cause in 38.5 percent of the elderly and 45.3 percent of the young (NS). Prolonged electrocardiographic monitoring established the diagnosis in 17 percent of the elderly but in only 8 percent of the young (p = 0.008). Syncope resulted in trauma in 39 percent of the elderly and in 32 percent of the young, but the elderly more often had major trauma. The two-year overall mortality was 26.9 +/- 3.4 percent in the elderly and 8.3 +/- 2.1 percent in the young (p less than 0.0001). The overall mortality and incidence of sudden death in the elderly with a cardiovascular diagnosis were similar to those in the young; however, in the elderly with a noncardiovascular diagnosis and syncope of unknown cause, the mortality and incidence of sudden death were higher. Multivariate analyses using mortality and sudden death as endpoints revealed that a cardiovascular cause of syncope was a very strong risk factor. In patients with a noncardiovascular cause or unknown cause of syncope, a history of congestive heart failure, older age, and male sex are important prognostic factors.
The American Journal of Medicine | 1991
Wishwa N. Kapoor
Syncope is a common medical problem and is caused by a wide variety of diseases ranging from physiologic derangements with few consequences to conditions that may be immediately life-threatening. Because of the large differential diagnosis, many diagnostic tests are available for its evaluation. However, a cause of syncope is not established in 38% to 47% of patients despite these tests. In those patients in whom a diagnosis can be assigned, the history and physical examination identify a potential cause in 49% to 85%. Furthermore, in 8% of additional patients, history and physical examination are suggestive of causes that need confirmation by specific tests. Routine blood tests rarely yield diagnostically helpful information. In those patients in whom a potential cause for syncope is identified, arrhythmias are diagnosed by electrocardiogram in 2% to 11% of patients, cardiac monitoring in 3% to 27% (telemetry or Holter), stress test in less than 1%, carotid massage in less than 1%, and electrophysiologic studies in less than 3%. Diagnosis of arrhythmias as a cause of syncope is problematic because symptomatic correlation during electrocardiographic monitoring is rarely found (approximately 4%), and as a result, there is no uniform agreement on diagnostic criteria for abnormalities. Similar problems exist in the use of electrophysiologic studies. Upright tilt testing and psychiatric examination may be useful in evaluation of recurrent syncope of unknown cause in patients without organic heart disease. Based on the results of recent studies, strategies for evaluation of patients with syncope are possible that utilize selective and goal-directed diagnostic testing.