Heart Flashcards
Where does coronary circulation begin?
Sinus of valsalva, where the RCA and LCA arise.
What are the coronary arteries?
Left main branches into LAD and LCX
RCA- usu goes to PDA (90% are right-dom)
but PDA can also come from LCX
What do the LAD and LCX supply?
LAD- anterior of LV, apex, IV septum, and the part of the RV that borders the IV septum
LCX is in groove that separates LA and LV, gives of marginal branches that supply LV.
What do RCA and PDA supply?
RCA is between RA and RV- supplies lateral portion of RV
PDA supplies AV node.
What are the Ao and mitral valves and where are they located?
Aortic valve- bt LV and Ao. 3 leaflets, 3 sinuses (one for RCA, one for LCA, on non-coronary sinus)
Mitral valve- bt LA and LV. 2 leaflets (anterior goes farther across the valve). Chordae tendenae attach leaflets to papillary muscles in LV.
What is the most common cause of mortality in the US?
Atherosclerosis of coronary arteries.
When does coronary artery stenosis become hemodynamically significant?
When the lumen decreases to 75% of the native area.
HPE for ischemic heart dz
Substernal chest pain/prs that radiates down arms, to jaw, teeth, back.
Usually happens during activity/emotional stress.
Evidence of PVD- diminished pulses,
Signs of ventricular failure- cardiomegaly, congestive heart failure, S3 or S4, MR murmur
Stable vs unstable angina
Stable- pain is reproducible and resolves with rest
Unstable- pain occurs at rest, does not improve with rest, is new and severe, is progressive. Suggests impending infarct.
Dx Eval for ischemic heart dz
EKG- signs of ischemia or old infarct
CXR- enlarged heart, pulm congestion
Exercise stress test- tells if myocardium is at risk
Nuclear med scans (thallium)- use to localize ischemic areas
Echo- myocardial fn and valve fn
Angiography- gold standard. shows lesions in coronary arteries.
RX for ischemic heart dz- who gets surgery?
Surgery for severe dz of LM or severe dz in the 3 mjr coronary arteries. Do coronary bypass.
What vessels are used during coronary bypass?
IMA (preferred)
Saphenous vein
Causes of Ao Stenosis (AS)
Bicuspid valve- px’s by 70yo.
Rheumatic fever- causes fusion and calcification
Degenerative stenosis- causes calcification.
Unicuspid valve (px’s early in life)
What is the physiologic response to AS?
LVH- this preserves stroke volume and cardiac output.
But, LVH and the increasing resistance of the valve result in decreased CO, pulm HTN, and myocardial ischemia
HPE
Pts have angina, syncope, dyspnea (dyspnea means it’s bad)
Hear a mid-systolic ejection murmur
Cardiomegaly, signs of CHF
Pulsus tardus et parvus
What is pulsus tardus et parvus
delayed/diminished pulse at the carotid