Coronary Artery Bypass Surgery.

Coronary Artery Bypass Surgery.

Coronary Artery Bypass Surgery.

Module 4: Discussion Mrs. K is a 60-year-old white female who presented to the ER with complaints of her heart “beating out of my chest.” She is complaining that she is having increased episodes of shortness of breath over the last month and in fact has to sleep on 4 pillows. She also notes that the typical swelling she’s had in her ankles for years has started to get worse over the past two months, making it especially difficult to get her shoes on toward the end of the day. In the past week, she’s been experiencing fatigue and decreased urine output. Her past history is positive for an acute anterior wall myocardial infarction and coronary artery bypass surgery. She was a 2 pack a day smoker, but quit 8 years ago. On physical examination, auscultation of the heart revealed a rumbling S3 gallop and inspiratory crackles. She has +3 edema of the lower extremities. 1. Discuss the pathophysiology of an S3 heart sound and include causes for an S3 gallop?

Coronary artery bypass surgery, also known as coronary artery bypass graft (CABG, pronounced “cabbage”) surgery, and colloquially heart bypass or bypass surgery, is a surgical procedure to  to an obstructed . A normal coronary artery transports  to and from the  itself, not through the main .

There are two main approaches. In one, the left , LITA (also called left internal mammary artery, LIMA) is diverted to the  of the . In this method, the artery is “” which means it is not detached from the origin. In the other, a  is removed from a leg; one end is attached to the  or one of its major branches, and the other end is attached to the obstructed artery immediately after the obstruction to restore blood flow.

CABG is performed to relieve  unsatisfactorily controlled by maximum tolerated anti-ischemic medication, prevent or relieve , and/or reduce the risk of death. CABG does not prevent  (heart attack). This surgery is usually performed with the heart stopped, necessitating the usage of . However, two alternative techniques are also available, allowing CABG to be performed on a beating heart either without using the cardiopulmonary bypass, a procedure referred to as “off-pump” surgery, or performing beating surgery using partial assistance of the cardiopulmonary bypass, a procedure referred to as “on-pump beating” surgery. The latter procedure offers the advantages of the on-pump stopped and off-pump while minimizing their respective side-effects.

CABG is often indicated when coronary arteries have a 50 to 99 percent obstruction. The obstruction being bypassed is typically due to , , or both. Arteriosclerosis is characterized by thickening, loss of elasticity, and calcification of the arterial wall, most often resulting in a generalized narrowing in the affected coronary artery. Atherosclerosis is characterized by yellowish plaques of , , and cellular debris deposited into the inner layer of the wall of a large or medium-sized coronary artery, most often resulting in a partial obstruction in the affected artery. Either condition can limit blood flow if it causes a cross-sectional narrowing of at least 50%.