In: Nursing
What is Tetralogy of fallot, give full pathophysiology for this condition
DEFINITION Tetralogy of fallot is a combination of four heart defects that are present at birth.The 4 congenital abnormalities are VENTRICULAR SEPTAL DEFECT,PULMONARY STENOSIS,MISPLACED OR OVER RIDING AORTA AND RIGHT VENTRICULAR HYPERTROPHY.
PATHOPHYSIOLOGY:Pulmonary stenosis can be classified according to the location.The common site is infudibular septum.This results in the impaired flow of deoxygenated blood into pulmonary artery,which leads to hypoxic episodes called as TET SPELLS.The ventricular septal defect is typically large;thus systolic pressures in the right and left ventricle are same.pathophysiology depends on degree of hyper trophy of right ventricle.RIGHT VENTRICULAR HYPERTROPHY occurs in response to high pressure that must overcome to pump blood through the RVOTO.This usually develops in utero and seen in xray as boot shape.OVERRIDING AORTA : When compared with normal heart ,the aorta in TOF is dilated and displaced .The aortic dilation is caused by an increase in blood flow through the aorta as it receives blood from both ventricles via VSD.
AORTA TOO LARGE (OA) leads to stealing space from pulmonary artery(cause PS)leads to prevents ventricular closure (VSD) leads to mixing of oxygenated blood with deoxygenated blood which results in decreased O2 supply to systemic circulation which gradually leads to (RVH).