Today, we had practical class in the central medical library. We managed to listen to few heart sounds with and without murmurs and some lung sounds too through the simulator.
At first, it looked very interesting to me.. listening from machines!! Never used such things before.. first time leh.. Then when class started, everything was like.. err.. everyone was so quiet, no one answered the doctor's questions... and he started.. THIS IS VERY BAD.. VERY BAD...
What causes split S2? Fixed split S2?
| 1) | Physiological split during inspiration |
| -During inspiration, negative intrathoracic pressure causes increased blood return into the right side of the heart, yet some slowing of emptying from the left side. The increased blood volume in the right ventricle causes the pulmonary valve to stay open longer during ventricular systole. This causes an increased delay in the P2 component of S2 relative to the A2 component. -During expiration, the positive intrathoracic pressure causes decreased blood return to the right side of the heart. The reduced volume in the right ventricle allows the pulmonary valve to close earlier at the end of ventricular systole, causing P2 to occur earlier, and "closer" to A2. | |
| 2) | Fixed split S2 |
| -Usually due to an atrial septal defect(ASD) or ventricular septal defect(VSD). -The ASD or VSD creates a left to right shunt that increases the blood flow to the right side of the heart, thereby causing the pulmonic valve to close later than the aortic valve independent of inspiration/expiration. | |
| 3) | Reverse splitting |
| -aortic stenosis (decreased LV outflow) -hypertrophic cardiomyopathy - left bundle branch block (delayed depolarization) | |
| 4) | Persistent splitting |
| - Right bundle branch block (from delayed pulmonic closure) |
Finally, just before leaving the library, the doctor reminded us that it's always good to start from the basics, that is, listen to more normal heart sounds. Practise on your friends! Practise Practise Practise!
Some sites for practising:
| 3M Littmann |
| Blaufuss Multimedia |
| Texas Heart Institute |
| Ausculatation Assistant |
4 comments:
i am really bad at listening to sounds, thanks for sharing.
i m not any better either.. lol.. nvm.. let's practise more!
Practise practise practise!!! let me auscultate!!!hohohoho!!!
davai..
ya zhdu
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