â¢ One plate is pushed beneath the other, or equivalent description. â¢ A trench may be formed at the subduction zone. (ii) Explain how subduction leads to volcanic activity. (2 points: 1 point for a correct explanation of one plate being pushed down and melted and 1. point for a correct explanation of molten material /magma rising to the surface near the zone)
Symptoms of atrial fibrillation occur when the upper chambers of the heart (atria) beat in a disorganized fashion. Atrial fibrillation is a type of arrhythmia. Characteristic symptoms include shortness of breath, palpitations, and lightheadedness.
What are the dangers of atrial fibrillation? Stroke; Why does atrial fibrillation cause stroke? What are the symptoms and signs of stroke? Heart failure; What are the symptoms and signs of atrial fibrillation? Some patients with atrial fibrillation may have no symptoms. The commonest symptoms are palpitations (a fluttering sensation in the chest). Other commonly reported symptoms of atrial fibrillation are shortness of breath, tiredness, chest pain, fatigue, dizziness and even loss of consciousness (syncope). The reasons why some people with atrial fibrillation experience symptoms, while others do not, are not completely known.