11. Cardiac Surgery Concepts Flashcards
CABG
coronary artery bypass
procedure where normal blood flow is restored to an area of the heart that has an obstructed coronary artery
3 steps for CABG
1- blood vessels are harvested
2- grafts are sewn proximal and distal to blockage
3- blood flows through graft and bypasses the blockage
what are the 3 vessels that can be harvested for CABG?
radial artery (not common) saphenous vein left internal mammary artery (LIMA) right internal mammary artery (RIMA)
where is proximal anastomosis
on the aorta
where is distal anastomosis
on the coronary artery distal to obstruction
In what case would you have 1 proximal anastomosis and 3 distal anastomosis’?
triple bypass using the LIMA
Which anastomosis’ usually get sewn on first?
the distals
What is the most commonly used graft?
left internal mammary artery LIMA
what is the LIMA usually anastomosed to?
LAD
Are arterial or venous grafts preferred for CABG?
arterial because they have to carry arterial blood
10 year rate of reocculsion for saphenous (%)
60% rate of reocculsion
10 year patency rate for LIMA (%)
90%
which is more patent the LIMA or radial artery?
LIMA
what is the most likely reason for the high patency of the LIMA?
it is a “live graft” meaning that the proximal origin from the subclavina is left intact
which is less invasive PCI or CABG?
PCI- percutaneous coronary intervention
balloon angioplasty or stenting (alternative to CABG)
better 5 year survival and patency? CABG or PCI?
CABG
lower risk of stroke at 5 years? CABG or PCI?
PCI
drug eluting stents
newer stents that slowly release a drug in order to slow the narrowing process
cardiopulmonary bypass machine
“heart lung machine”
functions as heart and lungs bc drains deox blood and oxygenates and removes CO2 then pumps back into body
purpose of CPB machine
keep the pt alive while the surgeon:
1. stop the heart
2. drain the blood
does the heart have to be arrested for cardiac surgery?
it is not mandatory but it is common and sometimes the surgeon will do it anyway
does the heart have to be arrested when the patient goes on cardiopulmonary bypass?
no, it is possible for the heart to remain beating while on bypass
however, it is most common to be arrested for bypass
how is the heart arrested?
surgeons inject cardioplegia into heart
how does cardioplegia stop the heart?
it alters transmembrane electrical potential in cardiac myocytes