Search results
Results from the WOW.Com Content Network
Pseudo-ST-depression, which is a wandering baseline due to poor skin contact of the electrode [3] Physiologic J-junctional depression with sinus tachycardia [3] Hyperventilation [3] Horizontal ST depression in V4, V5, V6 leads during a cardiac stress ECG. Other, non-ischemic, causes include: Side effect of digoxin [4] [3] Hypokalemia [4] [3]
Diagnosis is based on an ECG showing ST-segment depression at the J-point of 1 to 3 mm in leads V1 to V6, with tall and symmetrical T waves. [1] The ST-segment is upsloping and there is also often ST-segment elevation of 0.5 to 2 mm in lead aVR. [1] [2] The QRS complex is either normal or slightly wide. [1]
In electrocardiography, a strain pattern is a well-recognized marker for the presence of anatomic left ventricular hypertrophy (LVH) in the form of ST depression and T wave inversion on a resting ECG. [1] It is an abnormality of repolarization and it has been associated with an adverse prognosis in a variety heart disease patients.
The presentation and symptoms a patient can present with are varied and often dependent on the underlying cause of the junctional rhythm. Patient's can be asymptomatic for example, or experience difficulty breathing and chest pain if they have underlying congestive heart failure.
Schematic representation of normal ECG. In electrocardiography, the ST segment connects the QRS complex and the T wave and has a duration of 0.005 to 0.150 sec (5 to 150 ms). It starts at the J point (junction between the QRS complex and ST segment) and ends at the beginning of the T wave.
ECG would be abnormal in 75 to 95% of the patients. Characteristic ECG changes would be large QRS complex associated with giant T wave inversion [4] in lateral leads I, aVL, V5, and V6, together with ST segment depression in left ventricular thickening. For right ventricular thickening, T waves are inverted from V2 to V3 leads.
It is represented on the surface ECG by a so-called Ta wave. The clinical relevance of this is that, although a normal phenomenon, the nadir of the Ta wave can occur just after the QRS complex and cause ST depression similar to (and easily mistaken with) that occurring with disease states such as cardiac ischaemia. [9]
Under these criteria, an ECG is positive for an AMI in the presence of LBBB if any of the following criteria are present: ST deviation ≥1 mm (0.1 mV) concordant with QRS polarity in any ECG lead, thus including either: ST depression ≥1 mm (0.1 mV) concordant with QRS polarity, in any ECG lead.