A Red Flag ECG
2020; Lippincott Williams & Wilkins; Volume: 142; Issue: 19 Linguagem: Galês
10.1161/circulationaha.120.050249
ISSN1524-4539
AutoresMonica Monaghan, Shiva Sreenivasan,
Tópico(s)Cardiac electrophysiology and arrhythmias
ResumoHomeCirculationVol. 142, No. 19A Red Flag ECG Free AccessCase ReportPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissionsDownload Articles + Supplements ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toSupplemental MaterialFree AccessCase ReportPDF/EPUBA Red Flag ECG Monica Monaghan, PhD, MBBCh and Shiva Sreenivasan, MBBS Monica MonaghanMonica Monaghan Division of Cardiology (M.M.), Department of Medicine, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen, United Kingdom. Royal College of Surgeons in Ireland, St Stephen's Green, Dublin, Ireland (M.M.). and Shiva SreenivasanShiva Sreenivasan Shiva Sreenivasan, MBBS, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen BT74 6DN, United Kingdom. Email E-mail Address: [email protected] https://orcid.org/0000-0001-5066-8488 Division of Acute Medicine (S.S.), Department of Medicine, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen, United Kingdom. School of Medicine, Dentistry, and Biomedical Sciences, Queen's University, Belfast, United Kingdom (S.S.). Originally published9 Nov 2020https://doi.org/10.1161/CIRCULATIONAHA.120.050249Circulation. 2020;142:1871–1874ECG ChallengeA 72-year-old woman with essential hypertension, peripheral vascular disease, and previously undiagnosed type 2 diabetes mellitus presented to the emergency department with a 1-hour history of dyspnea, central chest discomfort, and diaphoresis. Clinical observations were normal apart from a sinus tachycardia. Chest auscultation revealed normal breath sounds and normal heart sounds with no murmurs. Initial serum high-sensitivity troponin T measurement was elevated at 57 ng/L (normal <15). A 12-lead ECG was performed (Figure 1).Download figureDownload PowerPointFigure 1. Twelve-lead ECG on admission.What does the ECG show? Can you predict which epicardial coronary artery is compromised and causing myocardial ischemia?Please turn the page to read the diagnosis.Response to ECG challengeThe 12-lead ECG shows sinus rhythm with first-degree heart block and a normal frontal QRS axis at approximately 0°. There is subtle ST-segment elevation in precordial lead V2, as well as in limb leads I and aVL. There is ST-segment depression in limb leads II, III, and aVF. There are small Q waves in leads V2, I, and aVL. This characteristic and often subtle noncontiguous pattern of ST-segment elevation in I, aVL, and V2, with ST-segment depression in III, is considered to be a reliable sign of acute occlusion of the first diagonal (D1) branch of the left anterior descending (LAD) coronary artery—or a "high lateral" myocardial infarction.1,2 It has also memorably been referred to as the South African Flag pattern.3This subtle ECG pattern was not appreciated at the initial assessment but was recognized when reviewed by a senior clinician 6 hours later. A repeat 12-lead ECG (Figure 2) at this time showed interval new anteroseptal Q waves suggestive of an evolving anterior transmural myocardial infarction. The patient complained of ongoing chest pain and was transferred to the interventional cardiology service situated at a separate hospital. On arrival, the patient was pain-free and hemodynamically stable with established Q waves and no further dynamic ECG changes. Subsequent cardiac catheterization revealed extensive thrombus of the proximal LAD vessel with Thrombolysis In Myocardial Infarction (TIMI) grade 2 flow and occlusion of the first diagonal vessel (D1) (Movie in the Data Supplement). Left ventriculogram reported anterior segment hypokinesis and subsequent viability studies reported no viability in the territory supplied by the LAD or its epicardial branches. Transthoracic echocardiography (Movie in the Data Supplement) confirmed severe left ventricular systolic dysfunction with regional wall motion abnormalities, hypokinesia, and wall thinning of the myocardial segments supplied by the LAD. The patient was treated with evidence-based preventative and heart failure pharmacotherapy.Download figureDownload PowerPointFigure 2. Twelve-lead ECG 6 hours following admission."High lateral" myocardial infarction caused by D1 occlusion projects the ST-segment vector toward I, aVL, and V2, and away from III (Figure 3). With the 12-lead ECG displayed in the conventional 3×4 landscape format, this subsequent characteristic pattern of ST-deviation in I, aVL, III, and V2 follows the pattern of the green stripe of the South African flag (Figure 4).Download figureDownload PowerPointFigure 3. Illustration of ST-segment vector projection toward leads I, aVL, and V2, and away from III and aVF in first diagonal branch (D1) coronary artery occlusion. LAD indicates left anterior descending coronary artery. Modified from https://commons.wikimedia.org/wiki/File:Coronary_arteries.svg, under the CC BY-SA license: https://creativecommons.org/licenses/by-sa/3.0/deed.en.Download figureDownload PowerPointFigure 4. Flag of South Africa superimposed onto 12-lead ECG showing characteristic ST-deviation pattern seen in first diagonal branch coronary artery occlusion. STD indicates ST-segment depression; and STE, ST-segment elevation.This case highlights the importance of recognizing subtle but important ischemic ECG changes. Early recognition of ST-elevation leads to timely revascularization and limits left ventricular systolic dysfunction. We propose that this patient presented with the symptoms and ECG characteristics of diagonal plaque rupture and high lateral myocardial infarction with thrombus formation that propagated retrogradely to the LAD/D1 bifurcation.We concur with the author of the original description of the South African Flag pattern that this mnemonic for ECG recognition of myocardial infarction caused by D1 occlusion is both easily understood and enjoyable to learn and teach.DisclosuresNone.Supplemental MaterialsData Supplement MovieFootnoteshttps://www.ahajournals.org/journal/circThe Data Supplement is available with this article at https://www.ahajournals.org/doi/suppl/10.1161/CIRCULATIONAHA.120.050249.Shiva Sreenivasan, MBBS, South West Acute Hospital, Western Health and Social Care Trust, Enniskillen BT74 6DN, United Kingdom. Email [email protected]netReferences1. Sclarovsky S, Birnbaum Y, Solodky A, Zafrir N, Wurzel M, Rechavia E. Isolated mid-anterior myocardial infarction: a special electrocardiographic sub-type of acute myocardial infarction consisting of ST-elevation in non-consecutive leads and two different morphologic types of ST-depression.Int J Cardiol. 1994; 46:37–47. doi: 10.1016/0167-5273(94)90115-5CrossrefMedlineGoogle Scholar2. Iwasaki K, Kusachi S, Kita T, Taniguchi G. Prediction of isolated first diagonal branch occlusion by 12-lead electrocardiography: ST segment shift in leads I and aVL.J Am Coll Cardiol. 1994; 23:1557–1561. doi: 10.1016/0735-1097(94)90656-4CrossrefMedlineGoogle Scholar3. Littmann L. South African flag sign: a teaching tool for easier ECG recognition of high lateral infarct.Am J Emerg Med. 2016; 34:107–109. doi: 10.1016/j.ajem.2015.10.022CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetailsCited By Littmann L (2021) A new electrocardiographic concept: V1-V2-V3 are not only horizontal, but also frontal plane leads, Journal of Electrocardiology, 10.1016/j.jelectrocard.2021.02.014, 66, (62-68), Online publication date: 1-May-2021. November 10, 2020Vol 142, Issue 19 Advertisement Article InformationMetrics © 2020 American Heart Association, Inc.https://doi.org/10.1161/CIRCULATIONAHA.120.050249PMID: 33166216 Originally publishedNovember 9, 2020 PDF download Advertisement SubjectsAcute Coronary SyndromesCoronary Artery Disease
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