This combination of atrial fibrillation and WPW is considered dangerous, and most antiarrhythmic drugs are contraindicated.When an individual is in normal sinus rhythm, the ECG characteristics of WPW are a short PR interval (less than 120 milliseconds in duration), widened QRS complex (greater than 120 milliseconds in duration) with slurred upstroke of the QRS complex, and secondary repolarization changes (reflected in ST segment-T wave changes).In individuals with WPW, electrical activity that is initiated in the SA node travels through the accessory pathway, as well as through the AV node to activate the ventricles via both pathways. Since the accessory pathway does not have the impulse slowing properties of the AV node, the electrical impulse first activates the ventricles via the accessory pathway, and immediately afterwards via the AV node. This gives the short PR interval and slurred upstroke of the QRS complex known as the delta wave.In case of type A pre-excitation (left atrioventricular connections), a positive R wave is seen in V1 ("positive delta") on the precordial leads of the electrocardiogram, while in type B pre-excitation (right atrioventricular connections), a predominantly negative delta wave is seen in lead V1 ("negative delta").People with WPW may have more than one accessory pathway – in some cases, as many as eight abnormal pathways have been found. This has been seen in individuals with Ebsteins anomaly.Wolff–Parkinson–White syndrome is sometimes associated with Lebers hereditary optic neuropathy, a form of mitochondrial disease. Risk stratification
WPW carries a small risk of sudden death, presumably due to rapidly conducted atrial fibrillation causing ventricular fibrillation.
For snakes that are usually patterned in colours, they appear as a faint blue, peach or yellowish. In these cases, there has been a genetic mutation in the melanin and pigment delivery. The appearance comes from the inability for full colours to be present, such as black, red, brown and others. The eyes of an albino snake are typically red or pink. Albino snakes can remain in the sunlight for several hours with minimal harm. Corn snakes and snakes of larger types, such as a boa or diamondback snakes, are the most commonly affected by albinism often appearing to be a pinkish or yellowish colour.Albino tortoises and turtles are uncommon; Sulcata tortoises are the most likely type of turtle to express albinism. The shells have an almost yellow colouration and they have pink eyes. For turtles, a pure white colour is nearly impossible, even with albinism. Albino turtles can have a longer lifespan than many other albino animals; their hard shells help to prevent predation and other environmental challenges. Vision and sensory organs are slightly affected.In 2012, an albino anole was reported and photographed. In 2007, it was reported that an albino stumpy-tail lizard (possibly a shingleback lizard), approximately 12 cm (4.7 in) long and roughly 1 year old, had been found in Victoria, Australia.There are three known "albino" strains of leopard gecko, however, breeders state that albinos are generally recognized by their lack of black pigment and having red eyes is not a requirement to be considered an albino.