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.
Freeform swimming pools are most often constructed of concrete or vinyl. After a hole shape is excavated in the ground and framework is in place, concrete is poured and can be filled to create any shape, size, or configuration. Vinyl-lined pools can be made into free-form designs that can feature a variety of designs.