Why is there diffuse ST elevation in pericarditis?
The electrocardiographic changes accompanying pericarditis consist of ST elevation in most of the leads of the 12-lead electrocardiogram. The source of this ST elevation is thought to be local inflammatory changes in the epicardium underlying the inflamed pericardium.
What are the ECG hallmarks of pericarditis?
Stage 1 accompanies the onset of acute pain and is the hallmark of acute pericarditis. ECG changes include diffuse concave upward ST elevation, except in leads aVR and V1 (usually depressed). T waves are upright in the leads with ST elevation, and the PR segment deviates opposite to P-wave polarity.
How does pericarditis cause ECG changes?
ECG of a patient with acute pericarditis. Diffuse concave-upward ST-segment elevation, ST-segment depression in aVR, and PR-segment depression is best demonstrated in leads II and V3. Note lack of reciprocal ST-segment changes, an important feature differentiating acute pericarditis from acute myocardial infarction.
What is PR depression?
Abstract. P-R segment depression is an early ECG change in the evolution of acute pericarditis. This is widely recognized in the USA and appears in several major emergency medicine texts. A telephone survey was conducted to gain an overview of the knowledge of accident and emergency career doctors in the UK.
What is diffuse ST depression?
Diffuse ST-segment depression with ST-segment elevation in the lead augmented vector right (aVR) in 12-lead electrocardiography may indicate the possibility of coronary artery disease involving the left main coronary artery or proximal left anterior descending artery, pulmonary embolism or takotsubo cardiomyopathy.
What is diffuse ST elevation?
ST elevation only occurs in full thickness infarction. Prinzmetal’s angina. Acute pericarditis ST elevation in all leads (diffuse ST elevation) is more common with acute pericarditis. Left ventricular aneurysm. Blunt trauma to the chest resulting in a cardiac contusion.
What causes PR depression?
PR segment elevation or depression in patients with myocardial infarction indicates concomitant atrial ischaemia or infarction. This finding has been associated with poor outcomes following MI, increased risk for the development of atrioventricular block, supraventricular arrhythmias and cardiac free-wall rupture.
What is normal PR interval?
The P-R Interval The first measurement is known as the “P-R interval” and is measured from the beginning of the upslope of the P wave to the beginning of the QRS wave. This measurement should be 0.12-0.20 seconds, or 3-5 small squares in duration.
How serious is ST depression?
Conclusions: In unstable coronary artery disease, ST-segment depression is associated with a 100% increase in the occurrence of three-vessel/left main disease and to an increased risk of subsequent cardiac events. In these patients an early invasive strategy substantially decreases death/myocardial infarction.