Ventricular septal defect

A ventricular septal defect (VSD) is a hole in the ventricular septum, the wall dividing the left and right ventricles of the heart. It is a common congenital heart defect, although restrictive muscular VSDs are not true pathological defects; they are typically just a delayed closure of the ventricular septum. They have an extremely high prevalence in newborns. The extent of the opening may vary from pin size to complete absence of the ventricular septum, creating one common ventricle. The ventricular septum consists of an inferior muscular and superior membranous portion and is extensively innervated with conducting cardiomyocytes.

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