Availability of a baseline Electrocardiogram changes the application of the Sclarovsky-Birnbaum Myocardial Ischemia
Esben A Carlsen1, Lia E Bang2, Lars Køber2
1Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
Background And Aims:
The electrocardiogram (ECG) based Sclarovsky-Birnbaum Ischemia Grade may be used to determine the prognosis of patients with ST-elevation myocardial infarction (STEMI). However, application of the method is based on assumption of the baseline QRS morphology. Thus, the aims of this study were to determine if the baseline QRS morphology was correctly assumed based on an ECG recorded during induced ischemia, and if reference to the baseline ECG altered the designated Ischemia Grade.
Methods:
Sixty-three patients with chronic ischemic heart disease that underwent elective percutaneous transluminal coronary angioplasty were included. Baseline ECG and ECG during the procedure were recorded. In the latter, Ischemia Grade was classified according to assumed baseline QRS morphology. Then the baseline ECG was used as reference and Ischemia Grade was determined based on change from the baseline ECG.
Results:
In 66.6% (42/63) of patients the criteria for STEMI were fulfilled; the incidence was similar between left anterior descending (LAD) and right coronary artery (RCA) occlusion. In LAD patients who fulfilled STEMI criteria, assumption of baseline QRS morphology in involved leads was accurate in only 35% (7/20) and this altered the Ischemia Grade in 10% (2/20) of patients. In RCA patients who fulfilled STEMI criteria, assumption of baseline QRS morphology in involved leads was accurate in 77.3% (17/22) and this altered the Ischemia Grade in 9.1% (2/22) of patients.
Conclusion:
Application of the Sclarovsky-Birnbaum Ischemia Grade with reference to a baseline ECG altered Ischemia Grade in approximately 10% of patients. All patients that were reclassified were assigned a higher Ischemia Grade. Future research is needed to determine the impact of availability of the baseline ECG on the clinical diagnostic and prognostic performances of the Sclarovsky-Birnbaum Ischemia Grade.
Related Concept Videos
01:29Electrocardiogram
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
01:28Electrocardiogram Fundamentals
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin...
01:24ECG Interpretation of Rhythms
Components of the Electrocardiogram
The primary components of a normal ECG waveform in Normal sinus rhythm(NSR) include the P wave, PR interval, QRS complex, ST segment, T wave, and occasionally a U wave.
ECG waveforms are divided by vertical and horizontal lines at standard intervals.
The horizontal axis measures time and rate, and the vertical axis measures amplitude or voltage....
01:19Acute Coronary Syndrome II: Pathophysiology and Clinical Manifestations
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
01:30Acute Coronary Syndrome III: Diagnostic Studies