Search results
Results from the WOW.Com Content Network
Schematic representation of a normal sinus rhythm ECG wave. Diagram showing how the polarity of the QRS complex in leads I, II, and III can be used to estimate the heart's electrical axis in the frontal plane. The QRS complex is the combination of three of the graphical deflections seen on a typical electrocardiogram (ECG or EKG). It is usually ...
A right bundle branch block typically causes prolongation of the last part of the QRS complex and may shift the heart's electrical axis slightly to the right. The ECG will show a terminal R wave in lead V1 and a slurred S wave in lead I. Left bundle branch block widens the entire QRS, and in most cases shifts the heart's electrical axis to the ...
The electrical axis of the heart is the net direction in which the wave of depolarization travels. It is measured using an electrocardiogram (ECG).Normally, this begins at the sinoatrial node (SA node); from here the wave of depolarisation travels down to the apex of the heart.
In the electrocardiogram, the intrinsicoid deflection is the downstroke of the QRS complex, from its highest amplitude until it reaches the baseline or lower. [1] Since the ventricles normally depolarize from inside to outside, this deflection reflects the depolarization vector from the endocardium to the epicardium.
There are several methods to determining the ECG axis. The easiest method is the quadrant method, where one looks at lead I and lead aVF. First, examine the QRS complex in both leads I and avF and determine if the QRS complex is positive (height of R wave > S wave), equiphasic (R wave = S wave), or negative (R wave < S wave).
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.
ECG beat. The Pan–Tompkins algorithm [1] is commonly used to detect QRS complexes in electrocardiographic signals ().The QRS complex represents the ventricular depolarization and the main spike visible in an ECG signal (see figure).
Cardiac aberrancy is a type of disruption in the shape of the electrocardiogram signal, representing abnormal activation of the ventricular heart muscle via the electrical conduction system of the heart. Normal activation utilizes the bundle of His and Purkinje fibers to produce a narrow (QRS) electrical