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What is The fouh hea sound is caused by? and explain in detail?
A fouh hea sound is common in persons who derive benefit from atrial contraction for ventricular filling as a result of decreased ventricular wall compliance and increased resistance to ventricular filling. For example, a fouh hea sound is often heard in older patients with left ventricular hyperophy.Ref: Guyton and Hall textbook of medical physiology 13th edition. Page:284