Left anterior fascicular block (LAFB) is an abnormal condition of the left ventricle of the heart, related to, but distinguished from, left bundle branch block (LBBB). It is caused by only the left anterior fascicle – one half of the left bundle branch being defective. It is manifested on the ECG by left axis deviation. It is much more common than left posterior fascicular block. Mechanism
Normal activation of the left ventricle (LV) proceeds down the left bundle branch, which consist of three fascicles, the left anterior fascicle, the left posterior fascicle, and the septal fascicle. The posterior fascicle supplies the posterior and inferoposterior walls of the LV, the anterior fascicle supplies the upper and anterior parts of the LV and the septal fascicle supplies the septal wall with innervation. LAFB — which is also known as left anterior hemiblock (LAHB) — occurs when a cardiac impulse spreads first through the left posterior fascicle, causing a delay in activation of the anterior and upper parts of the LV. Although there is a delay or block in activation of the left anterior fascicle there is still preservation of initial left to right septal activation as well as preservation of the inferior activation of the LV (preservation, on the EKG, of septal Q waves in I and aVL and predominantly negative QRS complex in leads II, III, and aVF). The delayed and unopposed activation of the remainder of the LV now results in a shift in the QRS axis leftward and superiorly, causing marked left axis deviation.
Diagnosis
Types
Granuloma annulare may be divided into the following types:: 703–5 
Localized granuloma annulare
Generalized granuloma annulare
Patch-type granuloma annulare
Subcutaneous granuloma annulare
Perforating granuloma annulare

Treatment
Because granuloma annulare is usually asymptomatic and self-limiting with a course of about 2 years, initial treatment is generally topical steroids or calcineurin inhibitors; if unimproved with topical treatments, it may be treated with intradermal injections of steroids. If local treatment fails it may be treated with systemic corticosteroids. Treatment success varies widely, with most patients finding only brief success with the above-mentioned treatments. Most lesions of granuloma annulare disappear in pre-pubertal patients with no treatment within two years while older patients (50+) have rings for upwards of 20 years. The appearance of new rings years later is not uncommon. History
The disease was first described in 1895 by Thomas Colcott Fox as a "ringed eruption of the fingers", and it was named granuloma annulare by Henry Radcliffe Crocker in 1902. See also
Granuloma
Necrobiosis lipoidica

References
External links
DermNet dermal-infiltrative/granuloma-annulare