{"id":64412,"date":"2025-08-06T18:32:14","date_gmt":"2025-08-06T13:02:14","guid":{"rendered":"https:\/\/johnsonfrancis.org\/professional\/?p=64412"},"modified":"2025-08-06T18:32:18","modified_gmt":"2025-08-06T13:02:18","slug":"diagnostic-criteria-for-left-bundle-branch-block","status":"publish","type":"post","link":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/","title":{"rendered":"Diagnostic criteria for left bundle branch block"},"content":{"rendered":"<iframe loading=\"lazy\" width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/5E83fzql-Co?si=bA_fzsz2fBTZ-4yA\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n\n<p class=\"wp-block-paragraph\">Complete left bundle branch block has widening of the QRS complex to 120 ms or more. If LBBB pattern is seen with QRS width less than 120 ms, it may be called incomplete left bundle branch block, though that term is rarely used in practice.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Broad, notched or slurred R waves in lateral leads I, aVL, V5, V6.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Small or absent initial r waves in V1 and V2 followed by deep S wave. If the initial r is absent, then it is a QS complex without any subsequent R wave after the Q.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">No septal q waves in I, V5, V6. That is due to the absence of the initial left to right activation of the interventricular septum which occurs in the presence of normal conduction in the left bundle branch.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Prolonged time to peak R wave of >60 ms in V5, V6, indicating delayed completion of activation of left ventricle.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Complete left bundle branch block has widening of the QRS complex to 120 ms or more. If LBBB pattern is seen with QRS width less than 120 ms, it may be called incomplete left bundle branch block, though that term is rarely used in practice. Broad, notched or slurred R waves in lateral leads I, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":64413,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","footnotes":""},"categories":[9],"tags":[],"class_list":["post-64412","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-general"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Diagnostic criteria for left bundle branch block - All About Cardiovascular System and Disorders<\/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:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Diagnostic criteria for left bundle branch block - All About Cardiovascular System and Disorders\" \/>\n<meta property=\"og:description\" content=\"Complete left bundle branch block has widening of the QRS complex to 120 ms or more. If LBBB pattern is seen with QRS width less than 120 ms, it may be called incomplete left bundle branch block, though that term is rarely used in practice. Broad, notched or slurred R waves in lateral leads I, [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/\" \/>\n<meta property=\"og:site_name\" content=\"All About Cardiovascular System and Disorders\" \/>\n<meta property=\"article:published_time\" content=\"2025-08-06T13:02:14+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2025-08-06T13:02:18+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2025\/08\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1202\" \/>\n\t<meta property=\"og:image:height\" content=\"675\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Johnson Francis\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Johnson Francis\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/\"},\"author\":{\"name\":\"Johnson Francis\",\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/#\\\/schema\\\/person\\\/5441d907049b914770f4bd98fb57feec\"},\"headline\":\"Diagnostic criteria for left bundle branch block\",\"datePublished\":\"2025-08-06T13:02:14+00:00\",\"dateModified\":\"2025-08-06T13:02:18+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/\"},\"wordCount\":155,\"publisher\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/#\\\/schema\\\/person\\\/5441d907049b914770f4bd98fb57feec\"},\"image\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/wp-content\\\/uploads\\\/2025\\\/08\\\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg\",\"articleSection\":[\"General Cardiology\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/\",\"url\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/\",\"name\":\"Diagnostic criteria for left bundle branch block - All About Cardiovascular System and Disorders\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/wp-content\\\/uploads\\\/2025\\\/08\\\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg\",\"datePublished\":\"2025-08-06T13:02:14+00:00\",\"dateModified\":\"2025-08-06T13:02:18+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#primaryimage\",\"url\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/wp-content\\\/uploads\\\/2025\\\/08\\\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg\",\"contentUrl\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/wp-content\\\/uploads\\\/2025\\\/08\\\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg\",\"width\":1202,\"height\":675},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/diagnostic-criteria-for-left-bundle-branch-block\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Diagnostic criteria for left bundle branch block\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/#website\",\"url\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/\",\"name\":\"All About Cardiovascular System and Disorders\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/#\\\/schema\\\/person\\\/5441d907049b914770f4bd98fb57feec\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/#\\\/schema\\\/person\\\/5441d907049b914770f4bd98fb57feec\",\"name\":\"Johnson Francis\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g\",\"caption\":\"Johnson Francis\"},\"logo\":{\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g\"},\"description\":\"Former Professor of Cardiology, Calicut Govt. Medical Kozhikode, Kerala, India. Editor-in-Chief, BMH Medical Journal\",\"url\":\"https:\\\/\\\/johnsonfrancis.org\\\/professional\\\/author\\\/jf\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Diagnostic criteria for left bundle branch block - All About Cardiovascular System and Disorders","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:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/","og_locale":"en_US","og_type":"article","og_title":"Diagnostic criteria for left bundle branch block - All About Cardiovascular System and Disorders","og_description":"Complete left bundle branch block has widening of the QRS complex to 120 ms or more. If LBBB pattern is seen with QRS width less than 120 ms, it may be called incomplete left bundle branch block, though that term is rarely used in practice. Broad, notched or slurred R waves in lateral leads I, [&hellip;]","og_url":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/","og_site_name":"All About Cardiovascular System and Disorders","article_published_time":"2025-08-06T13:02:14+00:00","article_modified_time":"2025-08-06T13:02:18+00:00","og_image":[{"width":1202,"height":675,"url":"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2025\/08\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg","type":"image\/jpeg"}],"author":"Johnson Francis","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Johnson Francis","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#article","isPartOf":{"@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/"},"author":{"name":"Johnson Francis","@id":"https:\/\/johnsonfrancis.org\/professional\/#\/schema\/person\/5441d907049b914770f4bd98fb57feec"},"headline":"Diagnostic criteria for left bundle branch block","datePublished":"2025-08-06T13:02:14+00:00","dateModified":"2025-08-06T13:02:18+00:00","mainEntityOfPage":{"@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/"},"wordCount":155,"publisher":{"@id":"https:\/\/johnsonfrancis.org\/professional\/#\/schema\/person\/5441d907049b914770f4bd98fb57feec"},"image":{"@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#primaryimage"},"thumbnailUrl":"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2025\/08\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg","articleSection":["General Cardiology"],"inLanguage":"en-US"},{"@type":"WebPage","@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/","url":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/","name":"Diagnostic criteria for left bundle branch block - All About Cardiovascular System and Disorders","isPartOf":{"@id":"https:\/\/johnsonfrancis.org\/professional\/#website"},"primaryImageOfPage":{"@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#primaryimage"},"image":{"@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#primaryimage"},"thumbnailUrl":"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2025\/08\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg","datePublished":"2025-08-06T13:02:14+00:00","dateModified":"2025-08-06T13:02:18+00:00","breadcrumb":{"@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#primaryimage","url":"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2025\/08\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg","contentUrl":"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2025\/08\/Diagnostic-Criteria-for-Left-Bundle-Branch-Block.jpg","width":1202,"height":675},{"@type":"BreadcrumbList","@id":"https:\/\/johnsonfrancis.org\/professional\/diagnostic-criteria-for-left-bundle-branch-block\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/johnsonfrancis.org\/professional\/"},{"@type":"ListItem","position":2,"name":"Diagnostic criteria for left bundle branch block"}]},{"@type":"WebSite","@id":"https:\/\/johnsonfrancis.org\/professional\/#website","url":"https:\/\/johnsonfrancis.org\/professional\/","name":"All About Cardiovascular System and Disorders","description":"","publisher":{"@id":"https:\/\/johnsonfrancis.org\/professional\/#\/schema\/person\/5441d907049b914770f4bd98fb57feec"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/johnsonfrancis.org\/professional\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":["Person","Organization"],"@id":"https:\/\/johnsonfrancis.org\/professional\/#\/schema\/person\/5441d907049b914770f4bd98fb57feec","name":"Johnson Francis","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g","caption":"Johnson Francis"},"logo":{"@id":"https:\/\/secure.gravatar.com\/avatar\/80861b82c3f559be9e413245c5643b6c483c93495507facfe32cf96ccd8bcffd?s=96&d=mm&r=g"},"description":"Former Professor of Cardiology, Calicut Govt. Medical Kozhikode, Kerala, India. Editor-in-Chief, BMH Medical Journal","url":"https:\/\/johnsonfrancis.org\/professional\/author\/jf\/"}]}},"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/posts\/64412","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/comments?post=64412"}],"version-history":[{"count":1,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/posts\/64412\/revisions"}],"predecessor-version":[{"id":64414,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/posts\/64412\/revisions\/64414"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/media\/64413"}],"wp:attachment":[{"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/media?parent=64412"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/categories?post=64412"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/johnsonfrancis.org\/professional\/wp-json\/wp\/v2\/tags?post=64412"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}