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Loud S1 and Fixed Splitting!

10K views 4 replies 5 participants last post by  tazreeakter240 
#1 ·
During a regular checkup of an 8-year-old child, you note a loud first heart sound with a fixed and widely split second heart sound at the upper left sternal border that does not change with respirations. The patient is otherwise active and healthy. Which of the following heart lesions most likely explains these findings?

A) Atrial septal defect
B) Ventricular septal defect
C) Isolated tricuspid regurgitation
D) Tetralogy of Fallot
E) Mitral valve prolapsed
 
#2 ·
a atrial septal defect
Second heart sound is widely split because the pulmonary hangout interval* is wide
Fixed because , the RV stroke volume does not show the normal respiratory changes.
This is due to dynamic phasic shunting across the IAS ( For example : During inspiration , if RA,RV volume gets augmented by 50ml from IVC inflow , in expiration this IVC augumentation is removed but a 50 ml augmentation from left atrium takes place , this keeps the RV diastolic , as well as systolic volume relatively constant.) This makes the 2nd heart sound fixed .
 
#3 ·
A.) Atrial Septal Defect: fixed splitting, pulmonary flow, diastolic rumbling.

During a regular checkup of an 8-year-old child, you note a loud first heart sound with a fixed and widely split second heart sound at the upper left sternal border that does not change with respirations. The patient is otherwise active and healthy. Which of the following heart lesions most likely explains these findings?

A) Atrial septal defect
B) Ventricular septal defect
C) Isolated tricuspid regurgitation
D) Tetralogy of Fallot
E) Mitral valve prolapsed
 
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