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

Abstract

Objective: To study the role of echocardiography in the stepwise evaluation of syncope. Design: A prospective observational study with an 18 month follow up. Setting: University teaching hospital providing primary and tertiary care. Subjects: 650 consecutive patients with syncope and clinical suspicion of an obstructive valvar lesion, or with syncope not explained by history, physical examination, or a 12 lead ECG, who underwent bidimensional Doppler transthoracic echocardiography. Main outcome measures: The causes of syncope were assigned using published diagnostic criteria. Echocardiography was considered diagnostic when confirming a suspected diagnosis, or when revealing occult cardiac disease explaining the syncope. Results: A systolic murmur was identified in 61 of the 650 patients (9%). Severe aortic stenosis was suspected in 20 of these and was confirmed by echocardiography in eight. Follow up excluded further cases of aortic stenosis. In patients with unexplained syncope (n = 155), routine echocardiography showed no abnormalities that established the cause of the syncope. Echocardiography was normal or non-relevant in all patients with a negative cardiac history and a normal ECG (n = 67). In patients with a positive cardiac history or an abnormal ECG (n = 88), echocardiography showed systolic dysfunction (left ventricular ejection fraction < 40%) in 24 (27%) and minor non-relevant findings in the remaining 64. Arrhythmias were diagnosed in 12 of the 24 patients with systolic dysfunction (50%), and in 12 of the 64 remaining patients (19%) (p < 0.01). Conclusions: Echocardiography was most useful for assessing the severity of the underlying cardiac disease and for risk stratification in patients with unexplained syncope but with a positive cardiac history or an abnormal ECG.

Prevalence of cardiac arrhythmias in pre-hospital tele-cardiology electrocardiograms of emergency medical service patients referred for syncope

“…In one study, none of the patients with syncope who had a negative cardiac history and a normal ECG had an abnormal echocardiogram. 16 For patients with isolated or rare syncopal episodes, who have no evidence of structural heart disease and a normal baseline ECG, the probability is high that the event was of a neurally mediated origin. These patients have a low mortality risk (although recurrences and physical injury are possible), and generally their evaluation can be completed entirely on an out-patient basis.…”

Can Echocardiographic Findings Predict Falls in Older Persons?

“…The level of risk increased according to the severity of the regurgitation. Valvular disease is known to cause syncope, the main evidence being for aortic valve stenosis and mitral valve prolapse [5], [6], [30], [31]. The guidelines on syncope state that structural heart disease can cause syncope when circulatory demands outweigh the impaired ability of the heart to increase its output.…”

Syncope in Patients with Organic Heart Disease

“…In many instances, other clinical circumstances indicate concomitant conditions, such as a myocardial infarction, which, though rare in the syncopal patient, is a marker of high risk. 23 For the patient who presents with syncope and no other cardiac diagnosis (but a suspected cardiac cause), the clinical history, coupled with the ECG and the echocardiogram, which may show structural and functional abnormalities, 64 are a useful beginning before tailoring the approach based on other clinical findings and risk markers manifest in the patient. Cardiac magnetic resonance imaging may be valuable for select patients.…”