> [!check] Objectives
> - Describe the indications for operation (CABG) and review the surgical techniques
> - Explain postoperative medical management
The risk of experiencing a cardiac event drastically increases with the number of locations in the body where [[atherosclerosis]] is present.
#### Coronary Artery Disease Treatment with CABG
The following types of [[coronary artery disease]] can be treated with [[coronary artery bypass|CABG]] to improve both quality of life, and survival.
###### Left Main Coronary Artery Disease
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>> In [[left main coronary artery disease]], there is > 50% stenosis/occlusion in the [[anterior interventricular artery|LAD]], particularly in the proximal portion. This restricts blood flow to pretty much the entire [[left ventricle]].
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>> ***Patients with left main CAD benefit from [[coronary artery bypass|CABG]] the most.***
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>>![[left main coronary artery disease.png|200]]
###### Left Main Equivalent
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>> In [[left main equivalent coronary artery disease|left main equivalent CAD]], there is > 70% stenosis in the proximal [[anterior interventricular artery|LAD]] and the [[left circumflex coronary artery|circumflex artery]], combined. It is relatively rare, and not as serious as a left main CAD, but still requires prompt treatment.
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>> ![[left main equivalent CAD.png|200]]
###### Triple Vessel Disease
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>> In [[triple vessel disease]], there is > 70% occlusion in all three of the major coronary arteries - the [[anterior interventricular artery|LAD]], the [[right coronary artery|RCA]], and the [[left circumflex coronary artery|circumflex artery]].
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>> ![[triple vessel disease.png|200]]
###### Double Vessel Disease
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>> In [[double vessel disease]], there is > 70% occlusion of two major coronary arteries - one of which **must** be the [[anterior interventricular artery|LAD]].
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>> ![[double vessel disease.png|500]]
# CABG Surgery
The surgery begins with harvesting the one of the <mark class="hltr-yellow">saphenous veins</mark> (either the [[great saphenous vein]] or the [[small saphenous vein]]).
- in the past, this involved a super long incision in the leg, accompanied by significant edema and pain that would sometimes last for years
- now, this part of the surgery can be done **endoscopically**, which only involves one or two small incisions, and virtually no infection, pain, or edema post-surgery
As an alternative to the saphenous vein, the [[radial artery]] in the patient's non-dominant arm can be harvested. The arm is relatively less resistant to infection, compared to the leg (less fat and more highly vascularized).
- this can also be done endoscopically
![[coronary artery bypass#Predictors of Mortality]]
#### Complications of CABG
![[coronary artery bypass#Complications]]
#### Outcomes:
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>> ###### Survival
>> - 92% at 5 years
>> - 81% at 10 years
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>> ###### Freedom from Angina
>> - 83% at 5 years
>> - 63% at 10 years
# Other Types of Surgery
#### Beating Heart Surgery
In patients who have atherosclerotic plaque formation in the aorta, clamping it can increase the risk of post-operative stroke, as the plaque can become broken up and travel to smaller vessels in the body.
To avoid this, **beating heart surgery** can be done, in which the heart is not paralyzed with potassium. Vaccuum devices are used to lift and immobilize parts of the heart to provide access and stabilization so that the surgery can be performed.
#### Robotic Heart Surgery
The most recent advances of heart surgery involve using robots. The surgeon is able to sit at a computer and use joysticks to control the robotic arms that have various instruments attached.
The robotic arms minimize the tremor that is naturally present in the hands, and allows for very precise surgical technique.
A huge benefit of robotic surgery is that it is minimally invasive.
One of the downsides is that there is no haptic or tactile feedback in the robots, so you can't be sure when you are getting resistance from the tissues.
# Post-Operative Risk Management
**CABG is not a curative procedure!** After the surgery, patients should engage in lifestyle changes and medical management to prevent [[coronary artery disease]] from causing more problems for them.
###### Lifestyle Changes
- weight loss
- smoking cessation
###### Medical Management
- [[asprin|ASA]] - patients should get on ASA within 6 hours of a vessel graft surgery and stay on it for life
- [[clopidogrel]] / [[ticagrelor]] - anti-platelet agents that help reduce the risk of thrombosis post-surgery
- [[statins]] - controls cholesterol
- [[beta-blockers]]
- [[ACE inhibitors]] (at a cardio-protective dose for life)
# How to Choose a Treatment
How do you determine whether your patient should get [[coronary artery bypass|CABG]], [[angioplasty|PCI]], or medical management?
It depends on the individual patient, of course.
> [!ECG] PCI vs CABG
> At 10 years, no significant difference exists in all-cause death between [[angioplasty|PCI]] and [[coronary artery bypass|CABG]]. However, [[coronary artery bypass|CABG]] provides a significant survival benefit in patients with [[triple vessel disease]], but not in patients with [[left main coronary artery disease|left main CAD]].
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> Diabetics tend to do much better with [[coronary artery bypass|CABG]].