- How does hand-grip increase blood in the heart? à hand-grip increases afterload à LV cannot eject
blood as readily à greater volume of blood left in the LV; it should be pointed out, however, that it
would be incorrect to say hand-grip increases preload, as this effect is indirect. - How does respiration relate to left- vs right-sided murmurs à inspiration makes right-sided murmurs
worse; exhalation makes left-sided murmurs worse. - Why does inspiration make right-sided murmurs worse? à inspiration à decreased intrathoracic
pressure à easier for blood to return to the RA à increased venous return à more preload in right
heart à worsening of TR, TS, PR, PS. - Why does inspiration soften left-sided murmurs? à decreased intrathoracic pressure à increased
pulmonary vascular compliance à transient decrease in pulmonary venous return to the LA à
decreased LA preload; it should be noted that although RA preload increases, this effect does not
carry over to the LA because of pulmonary vascular pooling. - Why does expiration soften right-sided murmurs? à expiration à increased intrathoracic pressure
à harder for blood to return to the RA à decreased venous return à less preload in right heart à
softening of TR, TS, PR, PS. - Why does expiration intensify left-sided murmurs? à expiration à increased intrathoracic pressure
à decreased pulmonary vascular compliance à transient increase in pulmonary venous return to the
LA à increased LA preload; it should be noted that although RA preload decreases, this effect does
not carry over to the LA because of pulmonary vascular compression. - What does VSD sound like? à USMLE will describe it two ways: 1) holosystolic murmur (aka
pansystolic) at the left sternal border (or lower left sternal border) with a parasternal heave or thrill;
- holosystolic murmur at the left sternal border with a diastolic rumble (weird, but in NBME Qs and
possibly an effect from movement across the valve even during the diastolic filling stage).
- Most common congenital heart defect? à VSD.
- If you patch/repair a VSD, what will happen to pressure in the LV, RV, and LA? (up or down arrows) à
repairing a VSD will cause up LV, down RV, down LA à the down always confuses people à repair of
VSD means less blood entering RV à less blood going back through the lungs to the LA.