Diagnosing syncope. Part 1: Value of history, physical examination, and electrocardiography. Clinical Efficacy Assessment Project of the American College of Physicians

PURPOSE: 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.     

Retrospective evaluation of urea and creatinine blood levels in calves with diarrhea

Heart myxoma is the most common cardiac neoplasm in adult, even if its biologic profile remains uncertain. The clinicopathologic features of 6 cardiac myxomas in patients ranging in age from 42 to 58 years are described: 5 cases were located in atria, 1 occurred in the right ventricular wall, attached by a thin pedicle to the wall next to the pulmonary artery. Grossly myxomas are generally pedunculated and average 2 to 8 cm in diameter. They appear gelatinous and polypoid, sometimes with areas of hemorrhage. Microscopic examination of specimens of myxomas removed at operation reveals the myxomatous nature of the stroma composed of abundant mucopolysaccharidic matrix, containing stellate or polyhedral cells, singly or in small clusters, and occasional blood vessels. In other cases, the matrix stains more deeply and reticulin fibers and occasional strands of collagen are evident. Immunohistochemical study reveals tumoral positivity for smooth muscle actin cells and for vimentin. In addition, endothelial cells in intramyxomatous vascular channels are positive for factor VIII and CD-34 endothelial markers. Myxomas were diagnosed in patients in whom the symptoms and signs of cardiac tumor may have been attributed to other causes. The clinical pictures produced by cardiac myxomas include non specific manifestations and mechanical interference with cardiac function. The symptoms may simulate a wide variety of other cardiac conditions (mitral valve disease, embolic phemomena, tricuspid valve disease, sudden unexpected death). A wide local excision is needed to assure that the myxoma does not recur.     

Neurologic manifestations in trichinosis]

Neurologic manifestations are present in about 10-20 percent of patients with trichinosis. They could be a serious diagnostic problem in the absence of corresponding epidemiological data and typical symptoms and signs of the disease. In untreated patients the mortality rate is about 50%. Several pathogenic mechanisms are responsible for the neurological complications in trichinosis: obstruction of brain blood vessels by larvae, cysts or granulomas, toxic vasculitis with secondary thrombosis and haemorrhages, granulomatous inflammation of the brain parenchyma and allergic reaction. Neurotrichinosis is manifested with clinical symptoms and signs of meningitis, encephalitis, polyradiculoneuritis, poliomyelitis, myastenia gravis, paresis and paralysis, with the clinical picture of systemic disease of the connective tissue involving the nervous system and, extremely rare, as a sinus thrombosis. Thus, the broad spectrum of neurological lesions in trichinosis is, probably, the results of the fact that Trichinella spiralis larvae, during haematogenic dissemination has no special affinity for particular parts of the nervous system. We present five patients with encephalitis and focal cerebral lesions in trichinosis. In one patient the neurologic manifestations were the only sign of the disease. We believe that all pathogenic mechanisms mentioned above, were involved in the onset of neurological manifestations in our patients. The diagnosis of the disease was based on the clinical picture, epidemiological data, microscopic identification of larvae in the muscular tissue, the presence of antibodies against Trichinella spiralis in cerebrospinal fluid (with preserved blood brain barrier) and in serum confirmed by IIF method, computerised tomography and magnetic resonance imaging of the brain, eosinophilia in the peripheral blood picture. One patient died, and in the remaining patients the course of the disease was favourable; they were discharged from the hospital with minimal neurologic sequelae.     

Partial congenital defect of the left pericardium: angiographic diagnosis and treatment by thoracoscopic pericardiectomy: case report

Twenty-six patients with an intracardiac myxoma underwent surgical resection at our institution from 1977 through 1992. Left atrial myxoma was diagnosed in 22 patients, left ventricular in 1, right atrial in 2, and right ventricular in 1. Six patients were asymptomatic; preoperative symptoms included dyspnea, arrhythmias, embolic episodes, and syncope. The diagnosis was established with transthoracic echocardiography in all cases but one. Surgery was performed in all cases with the aid of cardiopulmonary bypass with moderate hypothermia and cold crystalloid cardioplegia. One patient with a left ventricular myxoma died in a comatose state during the immediate postoperative period. Long-term clinical and echocardiographic evaluation was performed in 19 patients; results were excellent (all the patients were in New York Heart Association functional class I or II), and no recurrences were documented. The clinical characteristics, diagnostic methods, and surgical approach are presented and discussed.     

Nonpharmacologic treatment for heart arrhythmia]

Between 1990-1993 6 patients (4 females and 2 males) underwent the excision of the left atrial myxoma at The II Dept. of Cardiothoracic Surgery in Katowice. With the age range varying from 23 to 59 years. 3 patients presented symptoms of congestive heart failure with exertional dyspnoea, atrial fibrillation and syncope. 3 patients showed cerebral embolism. Every time the diagnosis was confirmed by the 2 D echocardiography. 4 patients were submitted the operation on the urgent basis because of occurring life threatening symptoms. All the patients were operated under cardiopulmonary bypass by the left atrial access, or in one case by the left and right atrial access simultaneously. The myxomas were removed and additionally the underlying endocardium or the full thickness of the interatrial septum, were excised. The surgical excision of the myxoma is the only acceptable therapy to cure. Without surgical treatment long term prognosis is fatal.     

The cardiovascular effects of lithium in man. A review of the literature

The medical literature since 1900 has been reviewed to determine the nature of lithium's cardiovascular effects. In therapeutic doses, lithium produces reversible T wave flattening and inversion in the electrocardiogram: rarely, it may cause sinus node dysfunction or ventricular arrhythmias. Patients with lithium toxicity almost always present with neurologic signs and symptoms. "Hypotension and cardiovascular collapse," alleged cardiotoxic manifestations of lithium, invariably follow days of coma. Given the possible cardiotoxic effect other psychopharmacologic agents and the hazards of withholding effective therapy in mania, it is concluded that lithium may be used safely in patients with cardiac disease if the dose is adjusted to the rate of lithium excretion and if serum levels of lithium are followed carefully. When used in patients with cardiac arrhythmias, frequent electrocardiographic monitoring is advised.     

Holter monitoring in the diagnosis and management of cardiac rhythm disturbances

Dynamic, long-term electrocardiography by the Holter technique has gained a definite and important role in cardiac diagnosis. Indications for its application include the diagnosis of ischemic heart disease, the assessment of antiarrhythmic therapy, the evaluation of function of artificial pacemakers, the investigation of physiologic correlates of known arrhythmias, the evaluation of the efficacy of antianginal therapy, and the assessment of the natural history of cardiac arrhythmias in various conditions. In our hands, the technique has proved most fruitful in the uncovering of arrhythmic correlates of transient neurologic disturbances or syncope, and in the precise characterization of patients suspected of having the sick sinus syndrome.     

Correlation of interleukin-6 gene expression to immunologic features in patients with cardiac myxomas

Cardiac myxomas, the most common primary heart tumors in adults, show a variety of clinical manifestations and laboratory findings correlated with elevated interleukin-6 (IL-6) serum concentration. The aim of this study was to determine the expression of IL-6 mRNA in myxoma tissue as a cause to frequent immunologic abnormalities in patients with such tumors. In our centers, we analyzed 17 surgically resected myxomas using the polymerase chain reaction (PCR) and found increased IL-6 mRNA expression in 14 of 17 cases. The serum IL-6 levels of the 14 patients, detected by enzyme-linked immunosorbent assay (ELISA) with mouse antihuman monoclonal antibody (mAb), were high preoperatively (> 6 pg/ml) and decreased to normal postoperatively (< or = 6 pg/ml). These same 14 patients exhibited significant autoimmune disorders preoperatively. The other 3 patients had normal serum levels of IL-6 (< or = 6 pg/ml) and did not present any serious signs and symptoms, and molecular analysis did not show overexpression of IL-6 mRNA in neoplasmic tissue. These results suggest that IL-6 is overproduced in myxoma tissue and secreted into the systemic circulation as a stimulator of the immunoregulatory system. Furthermore, this study indicates the promising role of molecular biology techniques in the research of pathophysiologic mechanisms of cardiac myxomas.     

Use of an extended monitoring strategy in patients with problematic syncope. Reveal Investigators

BACKGROUND: The conventional investigation of patients who present with syncope involves short-term ECG monitoring or provocative testing with head-up tilt and electrophysiological testing. A symptom-rhythm correlation is often difficult to obtain during spontaneous syncope because of its sporadic, infrequent, and unpredictable nature. METHODS AND RESULTS: We used a prolonged monitoring strategy to determine the cause of syncope in 85 patients (age, 59+/-18 years; 44 men) with recurrent undiagnosed syncope with an implantable loop recorder capable of cardiac monitoring for up to 18 months. During a mean of 10.5+/-4.0 months of follow-up, symptoms recurred in 58 patients (68%) 71+/-79 days (2.3+/-2.6 months) after implantable loop recorder insertion. An arrhythmia was detected in 42% of patients who recorded a rhythm during recurrent symptoms, with bradycardia present in 18 and tachycardia in 3. Five of the 18 bradycardic patients and 2 additional sinus rhythm patients received a clinical diagnosis of neurally mediated syncope. Patients who experienced presyncope were much less likely to record an arrhythmia during symptoms compared with recurrence of syncope (24% versus 70%, P=0.0005). There were no adverse events associated with recurrent symptoms, and there were no sudden deaths. Inability to freeze after an event occurred in 8 patients, and pocket infection occurred in 3. CONCLUSIONS: The strategy of prolonged monitoring is effective and safe in patients with problematic syncope.     

Prospective evaluation of unexplained syncope, dizziness, and falls among community-dwelling elderly adults

BACKGROUND: Unexplained syncope, dizziness, and falls may present a difficult diagnostic challenge to primary care and emergency room physicians. The aim of this study was to evaluate a diagnostic algorithm in the assessment of a cohort of community-dwelling elderly people with symptoms of unexplained syncope, falls, or dizziness. METHODS: Fifty-four consecutive elderly patients (mean age + SD = 76.4 + 8.0 years, range 61-91) were assessed over a 12-month period. Presenting symptoms were syncope in 33 patients (61.1%), unexplained falls without loss of consciousness in 10 patients (18.5%), and dizziness without loss of consciousness in 11 (20.4%), and true vertigo in 2 patients (3.7%). Patients were assessed systematically using the algorithm, followed up until a diagnosis was made, and appropriate preventive therapy or advice given. RESULTS: Diagnoses were obtained in 41 patients (75.9%). Of the 33 patients with syncope, the cause was identified in 23 (69.7%) as follows: vasovagal in 12, arrhythmia in 5, hypotensive drugs in 3, orthostatic hypotension in 2, and major anxiety with hyperventilation in 1. The cause of syncope remained uncertain in 10 patients. Among the 10 patients with nonsyncopal falls, the cause was identified in 9 as follows: drop attacks with associated knee osteoarthritis or quadriceps muscle weakness in 3, orthostatic hypotension in 2, and single cases of cerebellar ataxia, Parkinson's disease, otologic vertigo, and vertebrobasilar insufficiency. Of 11 patients with dizziness, 4 had vasovagal syncope, 2 had orthostatic hypotension, 2 had otologic vertigo, one had carotid sinus syndrome, and the cause remained obscure in 2. Nineteen of the 41 patients (46.3%) had at least one other abnormality that was possibly contributory to their symptoms. Five of the 13 patients without a clearcut diagnosis had abnormalities of possible significance, including first-degree heart block with fascicular block in 2 patients and individual patients with severe hypertension, aortic valve disease, and vasodepressor carotid sinus hypersensitivity. CONCLUSION: A targeted, problem-oriented algorithm indicates the diagnosis in three quarters of elderly patients with unexplained syncope, falls, and dizziness.     

Autonomic nervous system activity in essential hypertension: a comparison between dippers and non-dippers

This study examines whether race is a significant determinant of the diagnoses of acute myocardial infarction or angina pectoris in patients with symptoms suggestive of acute cardiac ischemia. The study population was comprised of 3401 (34%) African-American and 6600 (66%) white patients who presented to emergency departments with symptoms suggestive of acute cardiac ischemia. The main outcome measure was a diagnosis of acute myocardial infarction or angina pectoris. African Americans were younger, predominantly female, and more often had hypertension, diabetes mellitus, or smoked. The diagnosis of acute myocardial infarction was confirmed in 6% of African-American and 12% of white men, and in 4% of African-American and 8% of white women. After adjusting for age, gender, medical history, signs and symptoms, and hospital, African Americans were half as likely to develop acute myocardial infarction and were 60% as likely to have acute cardiac ischemia. Despite having less acute cardiac ischemia, African Americans in this study had high risk levels for coronary artery disease.     

Preclinical evaluation of radiopharmaceutical toxicological prerequisites

Right ventricular myxoma in elderly is very rare and this is the 36th case report of right ventricular myxoma in Japan. A healthy 71-year-old female with no symptoms or constitutional signs except heart murmur was hospitalized. Findings of transthoracic echocardiogram, CT scan, MRI and angiocardiogram demonstrated a mobile tumor in the right ventricular outflow tract. Transesophageal echocardiogram clearly revealed that the stalk was arising from the right ventricular free wall. Under cardiac arrest, right atriotomy was made and a gelatinous tumor (4.5 x 2 x 2 cm in size, 7.3 g in weight) was excised with 5 mm of surrounding endocardium and a few millimeters of underlying myocardium through the tricuspid valve. Histopathologically, the tumor was diagnosed as a myxoma. Her postoperative course was uneventful.     

Cardiac involvement in Becker muscular dystrophy

OBJECTIVES: The purpose of this study was to assess the incidence of myocardial involvement and the relation of cardiac disease to the molecular defect at the deoxyribonucleic acid (DNA) or protein level in Becker muscular dystrophy. BACKGROUND: Dystrophin gene mutations produce clinical manifestations of disease in the heart and skeletal muscle of patients with Becker muscular dystrophy. METHODS: Thirty-one patients underwent electrocardiographic and echocardiographic examination and 24-h Holter monitoring. The diagnosis was established by neurologic examination, dystrophin immunohistochemical assays or Western blot on muscle biopsy, or both, and DNA analysis. RESULTS: Electrocardiographic and echocardiographic findings were abnormal in 68% and 62% of the patients, respectively. Right ventricular involvement was detected in 52%. Left ventricular impairment was observed either as an isolated phenomenon (10%) or in association with right ventricular dysfunction (29%). Right ventricular disease was manifested in the teenagers, and an impairment of the left ventricle was observed in older patients. Right ventricular end-diastolic volumes were significantly increased compared with those in a control group. The left ventricular ejection fraction was significantly lower in older patients than in control subjects or younger patients. Life-threatening ventricular arrhythmias were detected in four patients. No correlations were found between skeletal muscle disease, cardiac involvement and dystrophin abnormalities. In our patients, exon 49 deletion was invariably associated with cardiac involvement. Exon 48 deletion was associated with cardiac disease in all but two patients. CONCLUSIONS: The cardiac manifestation of Becker muscular dystrophy is characterized by early right ventricular involvement associated or not with left ventricular impairment. Exon 49 deletion is associated with cardiac disease.     

Some new concepts of cardiac myxoma

The surgical treatment of cardiac myxoma in 211 consecutive cases (single tumor in 204 cases, multiple in 7, and recurrent in 3) from Dec. 1975 through Dec. 1993 was reviewed. Totally 228 myxomas were found and 215 operations performed. Data from this series and literature show that there were some complicated cases so that cardiac myxoma can not be simply regarded as a benign tumor only, but may be classified into two kinds: simple (or sporadic) cardiac myxoma and complicated cardiac myxoma. The latter includes myxoma complex, familial myxoma, and myxoma from multicenters. The clinical features, main points of diagnosis and surgery are concisely summarized.     

Myxoma of the left atrium (author's transl)

Clinical picture, course and routine cardiological diagnostic methods may give important clues indicating the presence of myxoma of the left atrium, but a definite diagnosis can only be made using echocardiography or cineangiography. The former is free of risk and thus should always precede the latter. Three patients were observed with a stalked myxoma of the left atrium which could be demonstrated echocardiographically. Every proven myxoma should be operated on as soon as possible as otherwise sudden unexpected complications leading to death may occur. In patients with changing cardiological signs and changing clinical symptoms this tumour should be excluded promptly by echocardiography. Necropsy statistics do not accurately reflect the incidence.     

Chronic active hepatitis and cirrhosis in Wilson's disease

A 32-year-old woman was found to have chronic active hepatitis and cirrhosis after exploratory celiotomy resulted in hepatic decompensation. Subsequent investigation confirmed the diagnosis of Wilson's disease. This case demonstrates that Wilson's disease may manifest itself as chronic active hepatitis as late as the fourth decade of life without neurologic symptoms or findings. Wilson's disease should be actively considered in patients with chronic active hepatitis or cirrhosis, even in older age groups and despite the absence of central nervous system manifestations.     

Syncope in bradycardic cardiac arrhythmias

Bradyarrhythmias, depending on the patient population, are the cause of syncope in 3 to 10%. Marked bradycardia or asystole can be due to impaired function of the sinus node (sinus node syndrome) or high-grade AV-conduction block as well as carotid sinus syndrome and pathologic vasodepressor reactions. In particular, in the presence of high-grade AV-block, the diagnosis of bradyarrhythmia-induced syncope can frequently be established on the basis of a standard ECG. One of the most common causes of syncope is functional impairment of the sinus node, in particular, an inadequate permanent sinus bradycardia, sinus node arrest or SA-block and paroxysmal atrial tachycardia alternating with atrial bradycardia. The method of choice for detecting suspected paroxysmal arrthythmias is ambulatory ECG monitoring but interpretation may be encumbered by the absence of concomitant symptoms during the registration. Frequently, the use of non-invasive methods alone, such as detailed history, ambulatory ECG and ECG exercise testing, will not render confirmatory findings to document the cause of syncope, that is, > 3 s pause in sinus rhythm or high-grade AV-block. In this situation, the question arises which patients should undergo electrophysiologic examination. Several studies have shown that in patients with a pathologic resting ECG (first degree AV-block, bundle branch block, inadequate sinus bradycardia) and cardiac disease, electrophysiologic studies will document a cause of syncope in more than 30%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Right atrial myxoma presenting as nonresolving pulmonary emboli: case report

A case of right atrial myxoma causing extensive pulmonary embolization is described. Five years elapsed between the initial consultation and the correct diagnosis. The patient has been free of symptoms for 3 years following surgical removal of the tumor. The clinical manifestations of right atrial myxoma, the differential diagnosis, and the atypical lung-scan features are discussed.     

The effectiveness of computer-assisted cognitive rehabilitation for persons with traumatic brain injury

Electroencephalographic (EEG) findings in syncope are reviewed. There are four major categories of syncope: neurally mediated (neurocardiogenic), neurologic, decreased cardiac output, and orthostatic hypotension. However, regardless of cause, whether the syncope is due to a vasovagal effect, a cardiac arrhythmia, an epileptic seizure, or hypotension, EEG findings are similar and reflect cerebral hypoperfusion. Initially there may be a slowing of background rhythms. This is followed by high amplitude delta activity, maximal anteriorly. If the hypoperfusion persists there is subsequent flattening of the EEG. The EEG returns to normal in the reverse sequence. In cases with severe and prolonged ischemia, convulsive syncope may occur at the time of the EEG flattening. Although not an epileptic phenomena, clinically this is often mistaken for epilepsy. Conversely, epileptic disorders, such as the ictal bradycardia syndrome, may occasionally mimic syncope. Therefore, in patients in whom EEGs are performed for the evaluation of an episode of loss of consciousness, simultaneous ECG should be used.     

Hypersensitivity pneumonitis due to humidifier disease: seek and ye shall find

A rare case of "complex" cardiac myxoma is reported. Complex cardiac myxoma manifests with more constitutional signs than the sporadic type. These constitutional signs are known to be associated with the overproduction of interleukin-6 by cardiac myxomas. In our study, immunohistochemical staining of the myxoma for interleukin-6 was strongly positive. The serum interleukin-6 level decreased after surgical removal of the tumor and has remained undetectable for the past 2 years.