Changes

[[Image:VSD1.jpg|right|thumb|200px|<small><center>'''Ventricular septal defect'''. Courtesy of A. Jefferies</center></small>]]

[[Image:VSD1.jpg|right|thumb|200px|<small><center>'''Ventricular septal defect'''. Courtesy of A. Jefferies</center></small>]]

Often associated with other conditions E.g. [[Heart and Great Vessels Development - Pathology#Tetralogy_of_Fallot|Tetralogy of Fallot]].

Often associated with other conditions E.g. [[Tetralogy_of_Fallot|Tetralogy of Fallot]].

Usually occur high in the membranous region of the interventricular septum.  Blood flows from left to right ventricle during systole resulting in right ventricular overload, increased central venous pressure and pulmonary overcirculation.<br>

Usually occur high in the membranous region of the interventricular septum.  Blood flows from left to right ventricle during systole resulting in right ventricular overload, increased central venous pressure and pulmonary overcirculation.<br>

'''''Eisenmenger's Syndrome''''': chronic pulmonary overcirculation results in pulmonary hypertension and increased right-sided pressure.  This facilitates right to left shunting and reduced lung perfusion, leading on to cyanosis.

'''''Eisenmenger's Syndrome''''': chronic pulmonary overcirculation results in pulmonary hypertension and increased right-sided pressure.  This facilitates right to left shunting and reduced lung perfusion, leading on to cyanosis.