The hexaxial reference system is a diagram that is used to determine the heart's electrical axis in the frontal plane.
In electrocardiography, left axis deviation (LAD) is a condition wherein the mean electrical axis of ventricular contraction of the heart lies in a frontal plane direction between −30° and −90°. This is reflected by a QRS complex positive in lead I and negative in leads aVF and II.[1]
There are several potential causes of LAD. Some of the causes include normal variation, thickened left ventricle, conduction defects, inferior wall myocardial infarction, pre-excitation syndrome, ventricular ectopic rhythms, congenital heart disease, high potassium levels, emphysema, mechanical shift, and paced rhythm.[2]
Symptoms and treatment of left axis deviation depend on the underlying cause.
^Jenkins, Dean (1996). "The electrical axis at a glance". www.ecglibrary.com. Retrieved 2016-11-12.
^Kashou, Anthony H.; Basit, Hajira; Chhabra, Lovely (2021), "Electrical Right and Left Axis Deviation", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 29262101, retrieved 2021-07-26
and 29 Related for: Left axis deviation information
In electrocardiography, leftaxisdeviation (LAD) is a condition wherein the mean electrical axis of ventricular contraction of the heart lies in a frontal...
this is considered left axisdeviation. If the electrical axis is between +90° and +180° this is considered right axisdeviation (RAD). RAD is an ECG finding...
by only the left anterior fascicle – one half of the left bundle branch being defective. It is manifested on the ECG by leftaxisdeviation. It is much...
complexes. The axis may be normal but may be deviated to the left or right. There are also partial blocks of the left bundle branch: "left anterior fascicular...
is right axisdeviation and beyond −30° is leftaxisdeviation (the third quadrant of −90° to −180° is very rare and is an indeterminate axis). A shortcut...
diameter. Average thickness of the left ventricle, with numbers given as 95% prediction interval for the short axis images at the mid-cavity level are:...
room exists for enlargement of the left atrium along the anteroposterior axis. By approximating the shape of the left atrium as an ellipsoid, its volume...
bundle branch block (RBBB) with left anterior fascicular block (LAFB), manifested as leftaxisdeviation (LAD). RBBB and left posterior fascicular block (LPFB)...
branch, leading to a right axisdeviation seen on the ECG. The American Heart Association has defined a LPFB as: Frontal plane axis between 90° and 180° in...
primum defects leftaxisdeviation is seen in most patients with an axis of > -30 degrees and very few patients have right axisdeviation. In contrast ostium...
electrical axis in the frontal plane will be approximately +60°. Normal axis: -30° to +90° Leftaxisdeviation: -30° to -90° Right axisdeviation: +90° to...
right heart, left-sided heart failure, which affects the left heart, and biventricular heart failure, which affects both sides of the heart. Left-sided heart...
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...
apex displacement. An ECG may show left ventricular hypertrophy and signs of left heart strain. Leftaxisdeviation can be a sign of advanced disease....
systolic blood pressure, or Killip class of two or greater), ST-segment deviation, diabetes, serum creatinine, peripheral vascular disease, and elevation...
arrest Other / ungrouped hexaxial reference system Right axisdeviationLeftaxisdeviation QT Short QT syndrome T T wave alternans ST J wave ST elevation...
arrest Other / ungrouped hexaxial reference system Right axisdeviationLeftaxisdeviation QT Short QT syndrome T T wave alternans ST J wave ST elevation...
However, the left bundle branch still normally activates the left ventricle. These impulses can then travel through the myocardium of the left ventricle...
depression will be seen because they are the opposing leads of the cardiac axis. PR segment depression is highly suggestive of pericarditis. R wave in most...
digoxin Hypokalemia Right or left ventricular hypertrophy Intraventricular conduction abnormalities (e.g., right or left bundle branch block, WPW, etc...
arrest Other / ungrouped hexaxial reference system Right axisdeviationLeftaxisdeviation QT Short QT syndrome T T wave alternans ST J wave ST elevation...
period of time, the left ventricle can experience hypertrophy (grow larger) in a way that decreases the heart's effectiveness. Left ventricular hypertrophy...
genes involved with making heart muscle proteins. Other inherited causes of left ventricular hypertrophy may include Fabry disease, Friedreich's ataxia, and...
Least absolute deviations, a mathematical optimization technique Left anterior descending artery, a coronary artery branch Leftaxisdeviation, a condition...
morphology. Positive or negative concordance. Extreme Axisdeviation or NORTH WEST axis (axis between -90 and +180 degrees) Ventricular tachycardia can...
arrest Other / ungrouped hexaxial reference system Right axisdeviationLeftaxisdeviation QT Short QT syndrome T T wave alternans ST J wave ST elevation...
dysfunction is also associated with AF, which increases left atrial pressure, left atrial volume, size, and left ventricular hypertrophy, characteristic of chronic...
axisdeviation (RAD), the rare combination is considered to be highly suggestive of dilated or congestive cardiomyopathy. Echocardiogram shows left ventricular...
Global Information