{"id":3940,"date":"2026-02-13T10:20:32","date_gmt":"2026-02-13T16:20:32","guid":{"rendered":"https:\/\/drakarlacastolo.com\/?p=3940"},"modified":"2026-02-13T10:20:34","modified_gmt":"2026-02-13T16:20:34","slug":"dizziness-and-fainting-syncope-causes-and-cardiology-study","status":"publish","type":"post","link":"https:\/\/drakarlacastolo.com\/en\/blog\/diagnostic-evaluation\/dizziness-and-fainting-syncope-causes-and-cardiology-study\/","title":{"rendered":"Dizziness and fainting (syncope): causes and cardiologic workup"},"content":{"rendered":"<p>Severe dizziness or fainting can occur from relatively common things like dehydration, a sudden change in position, or a vasovagal episode. But in some cases, it can also be a sign of a heart problem (e.g., an arrhythmia). The difference is in the context, the accompanying symptoms and certain alarm data.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">The most important<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A fainting spell is not always serious, but if it is <strong>new<\/strong>, is repeated, occurs with <strong>effort<\/strong> or comes with <strong>chest pain, shortness of breath or palpitations<\/strong>, medical evaluation is required.<\/li>\n\n\n\n<li>It is <strong>urgency<\/strong> if fainting occurs during exercise, if there is significant injury, if there is prolonged confusion, or if accompanied by chest pain\/pressure, shortness of breath, severe palpitations or marked weakness.<\/li>\n\n\n\n<li>There is no single test that \u201csays it all\u201d: the study is decided based on your history, vital signs and a <strong>electrocardiogram (ECG)<\/strong>.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">What is syncope?<\/h2>\n\n\n\n<p>The <strong>syncope<\/strong> is a brief loss of consciousness (fainting) due to a temporary decrease in blood flow to the brain. It usually lasts seconds or a few minutes and the person usually recovers relatively quickly.<\/p>\n\n\n\n<p>Not everything that looks like fainting is syncope. There can also be:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Presyncope<\/strong> (feeling of \u201cI'm going to faint\u201d without losing consciousness)<\/li>\n\n\n\n<li>Vertigo dizziness (sensation of everything spinning around)<\/li>\n\n\n\n<li>Sugar crashes or other metabolic causes<\/li>\n\n\n\n<li>Seizures (have different characteristics)<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">When to go to the emergency room<\/h2>\n\n\n\n<p>Seek immediate attention if fainting or severe dizziness occurs in any of these scenarios:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>During the <strong>exercise<\/strong> or right at the end (not \u201cby heat\u201d clearly identifiable)<\/li>\n\n\n\n<li>With <strong>chest pain or pressure<\/strong> or lack of air<\/li>\n\n\n\n<li>With <strong>palpitations<\/strong> very fast or irregular before fainting<\/li>\n\n\n\n<li>With fainting at rest without warning (no \u201cI felt sick before\u201d)<\/li>\n\n\n\n<li>With <strong>confusion<\/strong> prolonged after the event<\/li>\n\n\n\n<li>With <strong>severe weakness<\/strong>, very altered vision or slurred speech<\/li>\n\n\n\n<li>If there was a fall with a severe blow to the head, bleeding or major injury<\/li>\n<\/ul>\n\n\n\n<p>If there is also chest pain, refer to the article by <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/emergencies\/acute-myocardial-infarction\/\">acute myocardial infarction<\/a> and, if applicable, in <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/emergencies\/chest-pain-in-an-emergency\/\">chest pain: common causes and when is it an emergency?<\/a> (if it is already published in your blog).<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Frequent causes (and how to distinguish them)<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Common non-cardiac causes<\/h3>\n\n\n\n<p><strong>Vasovagal syncope (most common)<\/strong><br>It usually occurs by a reflex of the body lowering the pressure and\/or pulse. Typical clues:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Occurs with heat, prolonged standing, pain, stress or the sight of blood.<\/li>\n\n\n\n<li>Before fainting there may be nausea, sweating, pallor, \u201cI got cloudy\u201d or tinnitus.<\/li>\n<\/ul>\n\n\n\n<p><strong>Orthostatic hypotension (due to change of position)<\/strong><br>Happens when you get out of bed or out of a chair quickly. May be associated with dehydration, diarrhea\/vomiting, low intake or some medications.<\/p>\n\n\n\n<p><strong>Dehydration and heat stress<\/strong><br>More frequent with high temperatures, exercise, low water, alcohol or illness with fever.<\/p>\n\n\n\n<p><strong>Anemia or other systemic causes<\/strong><br>They can cause dizziness, fatigue and shortness of breath on exertion. Not always detected \u201cwith the naked eye\u201d.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Cardiac causes (to be carefully ruled out)<\/h3>\n\n\n\n<p><strong>Arrhythmias<\/strong><br>Beats that are too fast, too slow or irregular can lower cardiac output and cause fainting. If you notice heart \u201cskipping,\u201d check for <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/diagnostic-evaluation\/palpitations-common-causes-and-when-to-worry\/\">palpitations: common causes and when to worry about them<\/a> and, if applicable, <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/cardiac-conditions\/atrial-fibrillation-arrhythmias\/\">arrhythmias and atrial fibrillation<\/a>.<\/p>\n\n\n\n<p><strong>Structural or pumping problems<\/strong><br>Some heart conditions may be associated with fainting, especially if it occurs with exertion or is accompanied by shortness of breath. If you already have a diagnosis, check <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/cardiac-conditions\/cardiac-insufficiency\/\">cardiac insufficiency<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What may be included in the cardiological study of syncope?<\/h2>\n\n\n\n<p>The evaluation usually goes in this order (from the most basic to the most specific):<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Directed clinical history<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>What were you doing (resting, standing, exercising)?<\/li>\n\n\n\n<li>If there was prior warning (nausea, cold sweat, blurred vision)<\/li>\n\n\n\n<li>Medications (for blood pressure, diuretics, etc.)<\/li>\n\n\n\n<li>History (hypertension, diabetes, cholesterol, arrhythmias) and family history<\/li>\n<\/ul>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>Examination and vital signs<br>It includes checking blood pressure and pulse, sometimes in different positions (lying down and standing).<\/li>\n\n\n\n<li>Electrocardiogram (ECG)<br>It is the basic study to check the heart rhythm. You can see what it consists of here: <a href=\"https:\/\/drakarlacastolo.com\/en\/studies\/electrocardiogram-echocardiogram\/\">electrocardiogram (ECG)<\/a>.<\/li>\n\n\n\n<li>Studies on a case-by-case basis<br>Depending on the suspicion, the cardiologist may consider rhythm monitoring (if the symptom is intermittent), echocardiogram or other studies. If your episodes appear with activity, it may make sense to assess a <a href=\"https:\/\/drakarlacastolo.com\/en\/studies\/stress-test\/\">stress test<\/a>.<br>If there is also suspicion of poorly controlled pressure or significant variations, the following should be checked <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/diagnostic-evaluation\/blood-pressure-goals-home-blood-pressure-measurement\/\">blood pressure: goals and measurement at home<\/a> and, if applicable, the article of <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/diagnostic-evaluation\/hypertension\/\">hypertension<\/a>.<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">What to do before the consultation (to take advantage of it)<\/h2>\n\n\n\n<p>Carry this information (even if it is in cell phone notes):<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Date and time of the event<\/li>\n\n\n\n<li>What you were doing and what position you were in (standing, sitting, lying down).<\/li>\n\n\n\n<li>If there was previous warning (nausea, sweating, blurred vision, palpitations)<\/li>\n\n\n\n<li>Approximate duration and recovery<\/li>\n\n\n\n<li>If there was a blow or injury<\/li>\n\n\n\n<li>List of medications and dosages<\/li>\n\n\n\n<li>Recent pressure readings (if available)<\/li>\n<\/ul>\n\n\n\n<p>If you want a general preparation guide, you may also find the article by <a href=\"https:\/\/drakarlacastolo.com\/en\/blog\/diagnostic-evaluation\/blood-pressure-goals-home-blood-pressure-measurement\/\">blood pressure: goals and measurement at home<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">When to schedule a consultation (even if it is not an emergency)<\/h2>\n\n\n\n<p>Schedule cardiologic evaluation if:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>It was your <strong>first fainting spell<\/strong> without clear cause<\/li>\n\n\n\n<li>Repeats (more than one episode)<\/li>\n\n\n\n<li>Happens with effort or limits your activities<\/li>\n\n\n\n<li>Accompanied by palpitations, shortness of breath or chest pain\/pressure<\/li>\n\n\n\n<li>Have risk factors (hypertension, diabetes, high cholesterol) or relevant family history<\/li>\n<\/ul>\n\n\n\n<p>For a complete review you can review the <a href=\"https:\/\/drakarlacastolo.com\/en\/cardiac-checkup\/\">cardiological check up<\/a> o <a href=\"https:\/\/drakarlacastolo.com\/en\/contact\/\">schedule an appointment<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">References<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>European Society of Cardiology (ESC). <em>2018 ESC Guidelines for the diagnosis and management of syncope.<\/em>. <a href=\"https:\/\/academic.oup.com\/eurheartj\/article\/39\/21\/1883\/4939241\" target=\"_blank\" rel=\"noopener\">See source<\/a><\/li>\n\n\n\n<li>ACC\/AHA\/HRS. <em>2017 Guideline for the Evaluation and Management of Patients With Syncope.<\/em>. <a href=\"https:\/\/www.ahajournals.org\/doi\/10.1161\/CIR.0000000000000499\" target=\"_blank\" rel=\"noopener\">See source<\/a><\/li>\n\n\n\n<li>Mayo Clinic. <em>Fainting (syncope)<\/em>. <a>See source<\/a><\/li>\n\n\n\n<li>NHS. <em>Fainting<\/em>. <a href=\"https:\/\/www.nhs.uk\/conditions\/fainting\/\" target=\"_blank\" rel=\"noopener\">See source<\/a><\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Un mareo fuerte o un desmayo puede ocurrir por cosas relativamente comunes como deshidrataci\u00f3n, un cambio brusco de posici\u00f3n o un episodio vasovagal. Pero en algunos casos, tambi\u00e9n puede ser se\u00f1al de un problema del coraz\u00f3n (por ejemplo, una arritmia). La diferencia est\u00e1 en el contexto, los s\u00edntomas acompa\u00f1antes y ciertos datos de alarma. Lo [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3940","post","type-post","status-publish","format-standard","hentry","category-evaluacion-diagnostico"],"acf":[],"_links":{"self":[{"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/posts\/3940","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/comments?post=3940"}],"version-history":[{"count":1,"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/posts\/3940\/revisions"}],"predecessor-version":[{"id":3941,"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/posts\/3940\/revisions\/3941"}],"wp:attachment":[{"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/media?parent=3940"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/categories?post=3940"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/drakarlacastolo.com\/en\/wp-json\/wp\/v2\/tags?post=3940"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}