Characteristic Electrocardiogram Changes Research Articles

Acute Gastric Perforation Mimicking ST-Elevation Myocardial Infarction

An ST-elevation myocardial infarction (STEMI) is a medical emergency with an electrocardiogram (ECG) as the primary tool for rapid identification. Although STEMIs are known to produce characteristic ECG changes, several life-threatening conditions may mimic classic ECG patterns. In this article, we report a case of a 68-year-old male with a pneumoperitoneum secondary to gastric perforation with symptoms and ECG changes consistent with an inferior STEMI.

Improving the diagnostic accuracy of apical hypertrophic cardiomyopathy using machine learning

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Dr Hughes is supported by the British Heart Foundation (grant number FS/17/82/33222). Introduction The imaging criteria for diagnosis of apical hypertrophic cardiomyopathy (ApHCM) is a maximum wall thickness (MWT) ≥15mm. CMR enables detection of subtle phenotypic features (e.g. loss of apical tapering, cavity obliteration) and coupled with characteristic electrocardiogram changes, ApHCM can be diagnosed without overt hypertrophy. However, these patients are not captured by current diagnostic criteria. Purpose We sought to use a machine learning tool to quantify wall thickness and identify patients with ‘relative’ ApHCM that do not reach current diagnostic thresholds. Methods CMR images from 4118 healthy participants from the UK Biobank were segmented automatically with a clinically validated machine learning algorithm and wall thickness measured at all point in the myocardium by solving a solution to Laplace’s equation. MWT were pooled into 16 AHA segments and indexed to body surface area (BSA). The non-indexed and indexed segmental upper limit of normal was calculated as the mean + 3 standard deviations (the equivalent of 95% confidence interval after correcting for multiple [16] comparisons using the Bonferroni method). Results 73 overt ApHCM subjects (MWT>15mm) and 31 relative ApHCM subjects underwent CMR scanning. In healthy controls, the non-indexed (and indexed) upper limits were calculated for the apical-anterior 10.2mm (5.2 mm/m2), apical-septal 11.1mm (5.6 mm/m2), apical-inferior 10.5mm (5.3 mm/m2) and apical-lateral 10.1mm (5.2 mm/m2) segments. With a non-indexed cut-off, all (73 of 73) overt ApHCM and 84% (26 of 31) relative ApHCM were classified as having an abnormally thick apex. 3% (127 of 4118) of the healthy UK Biobank cohort were classified as abnormal, as expected. Using an indexed cut-off, all overt ApHCM and 87% (27/31) relative ApHCM were classified as abnormal, and 3% (123 of 4118) of the healthy UK Biobank cohort were misclassified. Conclusion We can successfully classify 87% of relative ApHCM patients from a normative reference range derived from a large cohort of healthy patients – a significant improvement on existing methods. We show that the specificity and sensitivity is increased when MWT is indexed to BSA. For practical clinical application, we recommend a cut-off of 10mm or an indexed cut-off of 5mm/m2 in any apical segment to diagnose apical LVH. Overt and relative apical HCM examplesHealthy controls AHA maps (non-indexed)

Accidental Consumption of Distinguished Substance in Disguise- A Rare Case of Minoxidil Poisoning

Minoxidil is a powerful direct acting vasodilator that was used clinically as an oral antihypertensive drug in combination with beta blockers and diuretics in cases of hypertension refractory to other antihypertensives. A 58-year-old male presented to the Emergency Department with an alleged history of accidental consumption of around 10 mL of 5% topical minoxidil solution. He had developed tachycardia, severe hypotension, and characteristic Electrocardiogram (ECG) changes with no obvious chest pain. He was treated with continuous intravenous (i.v.) crystalloids, dual inotropes and other supportive measures. The patient also developed acute pulmonary oedema and acute kidney injury. He responded to treatment and gradually improved haemodynamically with resolution of ECG changes and acute kidney injury. He was discharged seven days after admission. The patient showed resolution of characteristic ECG changes and improvement in haemodynamic condition of patient with supportive management in hospital.

Electrocardiogram changes and wall motion abnormalities in the acute phase of Tako-Tsubo syndrome.

The Tako-Tsubo syndrome is still rarely diagnosed in patients presenting with symptoms of acute myocardial ischaemia. It is accompanied by wall motion abnormalities of the left ventricle but significant narrowings or occlusions of epicardial coronary arteries are absent. We investigated a potential relationship between electrocardiogram (ECG) changes, wall motion abnormalities and gender influence of Tako-Tsubo syndrome in an Austrian cohort of Tako-Tsubo syndrome patients. We were recently able to describe four different anatomical types of Tako-Tsubo syndrome in 153 patients of the Austrian Tako-Tsubo syndrome registry. In the present retrospective analysis we investigated ischaemia-related changes in the first diagnostic ECG for the different types of Tako-Tsubo syndrome: the apical and the combined apical-midventricular type showed most frequently a ST elevation (41.1% and 35.3%), whereas the midventricular type of Tako-Tsubo syndrome was more often accompanied by T wave inversion (60%). ECG changes in relation to the Tako-Tsubo syndrome type were similar in women and men. There was no difference in the prevalence of clinical complications among patients presenting with ST elevation or left bundle branch block (14.5%) compared with patients without ST elevation (10.4%) (p=0.476). Patients with Tako-Tsubo syndrome show characteristic ECG changes in the first diagnostic ECG which are associated to some extent with the anatomical type of Tako-Tsubo syndrome, but these ECG changes were not related to clinical outcome.

Identification of the STEMI-equivalent de Winter Electrocardiogram Pattern After Ventricular Fibrillation Cardiac Arrest: A Case Report

BackgroundPatients with chest pain who have ST elevations on electrocardiogram (ECG) are at high risk for ST-elevation myocardial infarction (STEMI). Recent literature has reported various STEMI equivalents, which may be equally threatening. One STEMI equivalent, previously named the de Winter pattern, describes ECG changes where there are ST-segment depressions in the precordial leads in association with tall, symmetrical, hyperacute T-waves. These changes have been connected with proximal left anterior descending coronary artery occlusion. Case ReportWe have identified a case of the de Winter ECG pattern immediately after ventricular fibrillation cardiac arrest. A 33-year-old man presented with waxing and waning severe substernal chest pain. The patient was on no prior medications, and had no risk factors for acute coronary syndrome. The initial ECG showed ST depression, which was followed by normalization in a repeat ECG only minutes later. The patient then developed ventricular fibrillation cardiac arrest. After defibrillation, return of spontaneous circulation was achieved and subsequent ECGs demonstrated the de Winter ECG pattern. Why Should an Emergency Physician Be Aware of This?The characteristic ECG changes within the de Winter ECG pattern may be missed or misdiagnosed as nonspecific, reversible ischemia. This can significantly lengthen the transportation to a center equipped with a percutaneous coronary intervention laboratory, and thus the start of reperfusion therapy. It is imperative that all practitioners learn to identify this novel ECG pattern as a STEMI equivalent to ensure appropriate intervention in the cardiac catheterization laboratory.

An Atypical Familial Presentation of Brugada Syndrome: Can this be Considered as an Overlap Syndrome of the Long QT and Brugada Syndromes?

Long QT syndrome (LQTS) and Brugada syndrome (BrS) are well-known congenital channelopathies that can cause sudden cardiac death (SCD). Although various genetic mutations are associated with LQTS and BrS, an electrocardiogram (ECG) is typically preferred to genetic analysis as a diagnostic tool in clinical practice. However, care must be taken when using ECG in the diagnosis of LQTS or BrS, because the characteristic ECG changes of these syndromes are not observed consistently. The ECG pattern can be altered by various factors such as an aborted SCD, the autonomic nervous system, medication, circadian rhythms, and electrolyte imbalance. Here, we report our experience with a family in which the proband displayed an ECG pattern that initially suggested the presence of LQTS but was ultimately diagnosed as BrS, based on the findings of serial ECG follow-up, a drug provocation test, and genetic analysis. CASE REPORTS

Evaluation and management of wolff-Parkinson-white in athletes.

Context:Wolff-Parkinson-White (WPW) is a cardiac conduction system disorder characterized by abnormal accessory conduction pathways between the atria and the ventricles. Symptomatic patients classically present with palpitations, presyncope, or syncope that results from supraventricular tachycardia. While rare, sudden cardiac death may be the first manifestation of underlying disease and occurs more frequently in exercising individuals.Evidence Acquisition:Medline and PubMed databases were evaluated through 2012, with the following keywords: WPW, Wolff-Parkinson-White, pre-excitation, sudden cardiac death, risk stratification, and athletes. Selected articles identified through the primary search, along with relevant references from those articles, were reviewed for pertinent clinical information regarding the identification, evaluation, risk stratification, and management of WPW as they pertained to the care of athletes.Study Design:Systematic review.Level of Evidence:Level 1.Results:Diagnosis of WPW is confirmed by characteristic electrocardiogram changes, which include a delta wave, short PR interval, and widened QRS complex. Utilization of the electrocardiogram as part of the preparticipation physical evaluation may allow for early identification of asymptomatic individuals with a WPW pattern. Risk stratification techniques identify individuals at risk for malignant arrhythmias who may be candidates for curative therapy through transcatheter ablation.Conclusion:WPW accounts for at least 1% of sudden death in athletes and has a prevalence of at least 1 to 4.5 per 1000 children and adults. The risk of lethal arrhythmia appears to be higher in asymptomatic children than in adults, and sudden cardiac death is often the sentinel event. The athlete with WPW should be evaluated for symptoms and the presence of intermittent or persistent pre-excitation, which dictates further consultation, treatment, and monitoring strategies as well as return to play.

Electrocardiographic features and prognosis in acute diagonal or marginal branch occlusion

The aim of our study was to analyze electrocadiographic changes in patients with acute myocardial infarction related to the occlusion of diagonal (DG) or marginal (MG) branch. We selected 13 cases with DG and 12 with MG occlusion on angiography and evaluated their electrocardiogram (ECG) patterns on admission obtained in emergency department (ED) of university hospital with catheterization laboratory serving everyday interventional cardiology duty for ACS. Most characteristic ECG changes in acute occlusion of DG observed in 12 patients (92.3%) included ST-segment elevation in leads V 2 and V 3 (mean, 1.2 ± 0.5 mm; maximum, 1.7 mm) and ST-segment depression in leads II and III (mean, 0.9 ± 0.4 mm; maximum, 1.5 mm). Most characteristic ECG changes for acute occlusion of MG were ST-segment depression in leads V 5 and V 6 (mean, 0.9 ± 0.4 mm; maximal, 1 mm) observed in 11 (91.7%) patients, ST-segment depression in lead II (mean, 0.7 ± 0.2 mm; maximal, 0.8 mm) in 10 (83.3%,) and in leads V 2 and V 3, and aVF in 8 (66.7%) of cases. Risk of complications including cardiogenic shock and death was high in both groups especially during acute phase of myocardial infarction. Prevalence of borderline ECG changes in patients with acute coronary occlusion confirms how important is precise ECG interpretation usually initially done by ED physician.

The Full Stomach Test as a Novel Diagnostic Technique for Identifying Patients at Risk of Brugada Syndrome

Autonomic modulation, particularly high vagal tone, plays an important role in the occurrence of ventricular tachyarrhythmias in the Brugada syndrome. Food intake modulates vagal activity. We assessed the usefulness of a novel diagnostic technique, the "full stomach test," for identifying a high-risk group in patients with a Brugada-type electrocardiogram (ECG). In 35 patients with a Brugada-type ECG, we assessed 12-lead ECGs before and after a large meal, a pilsicainide pharmacological test, spontaneous ST-segment change, late potentials by signal-averaged ECG, microvolt T-wave alternans, and four other ECG parameters. These patients were divided into two groups (i.e., high-risk group [n = 17] and indeterminate risk group [n = 18]). The full stomach test was defined as positive when augmentation of characteristic ECG abnormalities was observed after meals. Thirteen patients had a prior history of life-threatening events such as aborted sudden death and syncope, with a total of 30 episodes. These episodes had a circadian pattern, at night and after meals. The full stomach test was positive in 17 of the study patients (49%). A positive test outcome was characterized by a higher incidence of a history of life-threatening events than a negative test outcome (P = 0.015, odds ratio = 7.1). In comparison between the two groups, the incidence (82%) of positive outcomes in the high-risk group was significantly higher than that (17%) in the indeterminate risk group (P = 0.0002). Characteristic ECG changes diagnostic of Brugada syndrome are augmented by a large meal. These data are associated with a history of life-threatening events in Brugada syndrome.

Electrocardiographic Changes Associated with Hypothermia Due to Acute Barbiturate Intoxication

Summary: A patient with hypothermia due to acute barbiturate intoxication is presented. Features not usually present in the electrocardiograms of hypothermic patients suggested myocardial infarction. Hypothermia in temperate climates is uncommon but this diagnosis should be suspected when the characteristic electrocardiogram changes are seen.

Hemodynamic reactions to angiographic media. A survey and commentary.

For some time it has been known that alterations in blood pressure, heart rate, cardiac output, and other body functions occur after the introduction of contrast media into the vascular system. The full nature and extent of the hemodynamic changes, however, are often not well appreciated, nor has there been general realization of their significance. It is the purpose of this paper to describe these changes, relate their mechanisms so far as they are known, gauge their importance, and indicate avenues available to the radiologist for minimizing them. The morbidity and mortality which still accompany several types of angiography are not a small concern, and we should endeavor to improve our present practices. Basic to this approach are the assumptions that any deviation from the patient's pre-examination hemodynamic status is undesirable and that the propensity of a contrast material to cause deviations from the prior hemodynamic status is a measure of its toxicity. The consequences of the surgical events by which a vessel is entered or the mechanical and electrical events due to the catheter and the injector apparatus will not be considered at this time. The Hemodynamic Responses The hemodynamic reactions to contrast media can be conveniently considered first on the basis of the type and site of injection. In general, introduction methods are of two main types: the slow injection of a compound into a peripheral vein for its excretion by the kidney or liver to visualize the collecting systems of those organs and the rapid injection of a more concentrated solution to visualize the vasculature of an organ or a region of the body. Intravenous Injection The relatively slow intravenous injection of urographic and Cholangiographie agents results in a degree of systemic hypotension due to a lowering of peripheral vascular resistance (38). Hypertonic solutions of many kinds have long been known to cause similar responses, and it is likely that the hemodynamic responses secondary to the urographic and Cholangiographic agents are in part due to their hypertonicity. Tachycardia is probably compensatory, as is the increase in venous pressure and pulmonary artery pressure which occurs concomitantly. Although there may be accompanying subjective responses, these hemodynamic reactions are not often serious. We are excluding from the present discussion patients who respond with abnormal intensity to the chemical nature of the material, the so-called drug idiosyncrasy reactions. Rapid peripheral intravenous injection of concentrated contrast media for angiocardiography produces a brief rise in arterial blood pressure followed by a prolonged fall. The diastolic pressure decreases more than the systolic, causing a rise in pulse pressure. The pulse rate also falls, and there are marked changes in the contour of the pulse. Venous pressure rises characteristic electrocardiogram changes consist of flattening, splitting, or inversion of T waves.