{"id":9832,"date":"2008-11-27T01:55:25","date_gmt":"2008-11-27T01:55:25","guid":{"rendered":"http:\/\/cardiophile.org\/?p=652"},"modified":"2024-01-14T10:50:32","modified_gmt":"2024-01-14T05:20:32","slug":"formulae-for-correction-of-qt-interval-qtc","status":"publish","type":"post","link":"https:\/\/johnsonfrancis.org\/professional\/formulae-for-correction-of-qt-interval-qtc\/","title":{"rendered":"Formulae for correction of QT interval: Calculation of QTc"},"content":{"rendered":"<p><iframe loading=\"lazy\" width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/UIIi_7HYOcw?si=mdNGBN-oRfZmGoGE\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" allowfullscreen><\/iframe><\/p>\n<h2><span style=\"color: #008000;\">Formulae for correction of QT interval: Calculation of QTc<\/span><\/h2>\n<p style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-22328 size-full aligncenter\" src=\"https:\/\/johnsonfrancis.org\/professional\/wp-content\/uploads\/2014\/12\/QT-Interval.png\" alt=\"QT interval on ECG\" width=\"600\" height=\"258\" \/><\/p>\n<p style=\"text-align: center;\"><span style=\"color: #0000ff;\"><em><strong>QT interval on ECG<\/strong><\/em><\/span><\/p>\n<p>Various formulae have been used for the correction of QT interval\u00a0with respect to the heart rate, even though the most popular one is the Bazett&#8217;s formula. Generally the QT intervals are corrected for a heart rate of 60 per minute. Some formulae use logarithmic parameters while others are linear.<\/p>\n<p><strong><span style=\"color: #0000ff;\">Logarithmic formulae for correction of QT interval (Log-linear)<\/span><\/strong><\/p>\n<p>Bazett&#8217;s formula: QT \/ (RR)<sup>0.5<\/sup><br \/>\n[Observed QT interval divided by root of RR interval, in seconds]<\/p>\n<p>Fridericia&#8217;s formula: QT \/ (RR)<sup>0.33<\/sup><br \/>\n[Observed QT interval divided by cube root of RR interval, in seconds]<\/p>\n<p>Baseline correction: QT \/ (RR)<sup>0.37<\/sup><br \/>\n[Observed QT interval divided by RR interval, in seconds raised to the power of 0.37]<\/p>\n<p><strong><span style=\"color: #0000ff;\">Linear formulae for correction of QT interval<\/span><\/strong><\/p>\n<p>Framingham formula: QT + 0.154 (1 \u2013 RR)<\/p>\n<p>Hodges formula: QT + 1.75 (HR \u2013 60)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Formulae for correction of QT interval: Calculation of QTc<\/p>\n","protected":false},"author":1,"featured_media":37971,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","footnotes":""},"categories":[6],"tags":[],"class_list":["post-9832","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-ecg-electrophysiology"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Formulae for correction of QT interval<\/title>\n<meta name=\"description\" content=\"Formulae for correction of QT interval: Calculation of QTc\" \/>\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\/formulae-for-correction-of-qt-interval-qtc\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" 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