{"id":10784,"date":"2026-06-28T03:05:20","date_gmt":"2026-06-28T03:05:20","guid":{"rendered":"https:\/\/cardiocases.com\/?post_type=ecg_case&p=10784"},"modified":"2026-07-02T11:40:20","modified_gmt":"2026-07-02T11:40:20","slug":"trace-1-3-av-block-with-trifascicular-block","status":"publish","type":"ecg_case","link":"https:\/\/cardiocases.com\/fr\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/","title":{"rendered":"Trace 1.3: AV block with trifascicular block"},"content":{"rendered":"","protected":false},"featured_media":9547,"template":"","ecg_case_type":[250],"language_ecgcase":[258],"class_list":["post-10784","ecg_case","type-ecg_case","status-publish","has-post-thumbnail","hentry","ecg_case_type-atrioventricular-block","language_ecgcase-english"],"acf":{"ecg_case_title":"Trace 1.3: AV block with trifascicular block","patient_description":"77-year-old man with dilated cardiomyopathy, admitted for syncope","quiz_question":"Regarding this ECG, which answer(s) is(are) true?","quiz_answer_1":"the rhythm is sinus","quiz_answer_2":"there is left atrial enlargement","quiz_answer_3":"there is right bundle branch block","quiz_answer_4":"there is first-degree AV block","quiz_answer_5":"there is left anterior fascicular block","correct_answer":["A","B","C","D","E"],"ecg_image":9547,"ecg_description":"Sinus rhythm (positive P waves in leads I, II, V5, V6, negative in aVR); left atrial enlargement (wide P wave, bifid in leads II, III, V4-V6, with wide negative component in V1); fixed and prolonged PR interval (240 ms): first-degree AV block; wide QRS (160 ms) with right bundle branch block pattern (large amplitude R wave in V1, wide S wave in V6) and left anterior fascicular block (left axis, rS pattern in inferior leads);","ecg_info_box":"Most often, the electrocardiographic pattern can only suggest the location of the block or the slowing of atrioventricular conduction. For example, an association on the electrocardiogram between right bundle branch block, left anterior fascicular block and prolonged PR interval does not necessarily reflect the presence of a trifascicular block. Demonstration of a long HV interval during an electrophysiological study confirms the diagnosis of trifascicular block with conduction delay in the remaining fascicule (left posterior hemibranch).","commentary_ecg":"This electrocardiogram shows a bifascicular block pattern (right bundle branch block + left anterior fascicular block) and a moderately prolonged PR. This combination is sometimes erroneously considered as a trifascicular block. This electrocardiogram alone does not confirm the presence of a trifascicular block, since the long PR may be the result of a slowing of conduction in the atrioventricular node (bifascicular block) instead of the left posterior hemibranch, the remaining fascicule. It is not solely an issue of semantics, since the prognosis differs according to the degree of progression of the conduction disorders. An electrophysiological study allows defining the site of the slowing explaining the prolongation of the PR interval by differentiating between a delay in the atrium or atrioventricular node (prolonged AH interval), a delay in the bundle of His (prolonged or split His potential) and a distal conduction delay in the branches and Purkinje network (prolonged HV interval). In this patient, there was a pathological HV interval at 90 ms, indicative of conduction slowing in the \u201cfunctional\u201d hemibranch confirming the presence of a trifascicular block.\r\n\r\nCertain electrocardiographic abnormalities reveal the presence of a trifascicular block: alternating left and right bundle branch block, alternating right bundle branch block\/left anterior fascicular block and right bundle branch block\/left posterior fascicular block.\r\n\r\nIn this patient, the probability of a complete atrioventricular block responsible for syncope was very high, justifying the implantation of a pacemaker.","ecg_info_post_answer":"\"\""},"yoast_head":"\nTrace 1.3: AV block with trifascicular block - Cardiocases<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/cardiocases.com\/fr\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Trace 1.3: AV block with trifascicular block - Cardiocases\" \/>\n<meta property=\"og:url\" content=\"https:\/\/cardiocases.com\/fr\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/\" \/>\n<meta property=\"og:site_name\" content=\"Cardiocases\" \/>\n<meta property=\"article:modified_time\" content=\"2026-07-02T11:40:20+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/cardiocases.com\/wp-content\/uploads\/2026\/03\/trace-1-3-ecg-scaled.png\" \/>\n\t<meta property=\"og:image:width\" content=\"2560\" \/>\n\t<meta property=\"og:image:height\" content=\"1263\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Dur\u00e9e de lecture estim\u00e9e\" \/>\n\t<meta name=\"twitter:data1\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/\",\"url\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/\",\"name\":\"Trace 1.3: AV block with trifascicular block - Cardiocases\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/cardiocases.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/cardiocases.com\\\/wp-content\\\/uploads\\\/2026\\\/03\\\/trace-1-3-ecg-scaled.png\",\"datePublished\":\"2026-06-28T03:05:20+00:00\",\"dateModified\":\"2026-07-02T11:40:20+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/#breadcrumb\"},\"inLanguage\":\"fr-FR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/#primaryimage\",\"url\":\"https:\\\/\\\/cardiocases.com\\\/wp-content\\\/uploads\\\/2026\\\/03\\\/trace-1-3-ecg-scaled.png\",\"contentUrl\":\"https:\\\/\\\/cardiocases.com\\\/wp-content\\\/uploads\\\/2026\\\/03\\\/trace-1-3-ecg-scaled.png\",\"width\":2560,\"height\":1263},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/cardiocases.com\\\/ecg_case\\\/trace-1-3-av-block-with-trifascicular-block\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/cardiocases.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Trace 1.3: AV block with trifascicular block\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/cardiocases.com\\\/#website\",\"url\":\"https:\\\/\\\/cardiocases.com\\\/\",\"name\":\"Cardiocases\",\"description\":\"Real cardiac device traces, pacemaker & ICD learning \u2014 built by electrophysiologists\",\"publisher\":{\"@id\":\"https:\\\/\\\/cardiocases.com\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/cardiocases.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"fr-FR\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/cardiocases.com\\\/#organization\",\"name\":\"Cardiocases\",\"url\":\"https:\\\/\\\/cardiocases.com\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/cardiocases.com\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/cardiocases.com\\\/wp-content\\\/uploads\\\/2025\\\/07\\\/cardiocases_logo.png\",\"contentUrl\":\"https:\\\/\\\/cardiocases.com\\\/wp-content\\\/uploads\\\/2025\\\/07\\\/cardiocases_logo.png\",\"width\":1755,\"height\":499,\"caption\":\"Cardiocases\"},\"image\":{\"@id\":\"https:\\\/\\\/cardiocases.com\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.linkedin.com\\\/company\\\/cardiocases\\\/\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Trace 1.3: AV block with trifascicular block - Cardiocases","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/cardiocases.com\/fr\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/","og_locale":"fr_FR","og_type":"article","og_title":"Trace 1.3: AV block with trifascicular block - Cardiocases","og_url":"https:\/\/cardiocases.com\/fr\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/","og_site_name":"Cardiocases","article_modified_time":"2026-07-02T11:40:20+00:00","og_image":[{"width":2560,"height":1263,"url":"https:\/\/cardiocases.com\/wp-content\/uploads\/2026\/03\/trace-1-3-ecg-scaled.png","type":"image\/png"}],"twitter_card":"summary_large_image","twitter_misc":{"Dur\u00e9e de lecture estim\u00e9e":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/","url":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/","name":"Trace 1.3: AV block with trifascicular block - Cardiocases","isPartOf":{"@id":"https:\/\/cardiocases.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/#primaryimage"},"image":{"@id":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/#primaryimage"},"thumbnailUrl":"https:\/\/cardiocases.com\/wp-content\/uploads\/2026\/03\/trace-1-3-ecg-scaled.png","datePublished":"2026-06-28T03:05:20+00:00","dateModified":"2026-07-02T11:40:20+00:00","breadcrumb":{"@id":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/#breadcrumb"},"inLanguage":"fr-FR","potentialAction":[{"@type":"ReadAction","target":["https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/"]}]},{"@type":"ImageObject","inLanguage":"fr-FR","@id":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/#primaryimage","url":"https:\/\/cardiocases.com\/wp-content\/uploads\/2026\/03\/trace-1-3-ecg-scaled.png","contentUrl":"https:\/\/cardiocases.com\/wp-content\/uploads\/2026\/03\/trace-1-3-ecg-scaled.png","width":2560,"height":1263},{"@type":"BreadcrumbList","@id":"https:\/\/cardiocases.com\/ecg_case\/trace-1-3-av-block-with-trifascicular-block\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/cardiocases.com\/"},{"@type":"ListItem","position":2,"name":"Trace 1.3: AV block with trifascicular block"}]},{"@type":"WebSite","@id":"https:\/\/cardiocases.com\/#website","url":"https:\/\/cardiocases.com\/","name":"Cardiocases","description":"Real cardiac device traces, pacemaker & ICD learning \u2014 built by electrophysiologists","publisher":{"@id":"https:\/\/cardiocases.com\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/cardiocases.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"fr-FR"},{"@type":"Organization","@id":"https:\/\/cardiocases.com\/#organization","name":"Cardiocases","url":"https:\/\/cardiocases.com\/","logo":{"@type":"ImageObject","inLanguage":"fr-FR","@id":"https:\/\/cardiocases.com\/#\/schema\/logo\/image\/","url":"https:\/\/cardiocases.com\/wp-content\/uploads\/2025\/07\/cardiocases_logo.png","contentUrl":"https:\/\/cardiocases.com\/wp-content\/uploads\/2025\/07\/cardiocases_logo.png","width":1755,"height":499,"caption":"Cardiocases"},"image":{"@id":"https:\/\/cardiocases.com\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.linkedin.com\/company\/cardiocases\/"]}]}},"_links":{"self":[{"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/ecg_case\/10784","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/ecg_case"}],"about":[{"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/types\/ecg_case"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/media\/9547"}],"wp:attachment":[{"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/media?parent=10784"}],"wp:term":[{"taxonomy":"ecg_case_type","embeddable":true,"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/ecg_case_type?post=10784"},{"taxonomy":"language_ecgcase","embeddable":true,"href":"https:\/\/cardiocases.com\/fr\/wp-json\/wp\/v2\/language_ecgcase?post=10784"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}