Atrial fibrillation and a corresponding enlargement of the left atrium may cause an increase in size of the mitral valve annulus. With a sinus rhythm, the mitral annulus undergoes dynamic changes during the cardiac cycle. For example, at the end of diastole the annular area is smaller than at the end of systole.
To determine who can perform aquatic therapy, we must define what aquatic therapy is. First, notice that aquatic therapy is considered a therapeutic procedure, not a modality. There are many technical and practical distinctions between the practice of aquatic therapy and the application of therapeutic modalities.
Swimming pool chemicals may also be used in hot tubs, spas, wading pools, and whirlpools. Various kinds of disinfectants and sanitizers are used but the chlorine type is the most common. The chlorine usually comes from chlorinating agents that release chlorine when they are dissolved in the water. Chlorine gas may be used in large pools.