Coronary artery bypass surgery (patient information)
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'Synonyms and keywords: Coronary artery bypass grafting, and colloquially heart bypass, bypass, bypass surgery, open heart surgery, or CABG (pronounced like cabbage), aortocoronary bypass (ACB). The term Coronary Artery Graft Surgery (CAGS) is often used outside the United States and should not be confused with Coronary Angiography (CAG).
Overview
Coronary Artery Bypass Graft (CABG) which is pronounced as "Cabbage", is a surgical procedure done to restore blood flow to the heart.The arteries of the heart get blocked due to calcium and fat deposits in the arteries which cause the blockage and eventually lead to a heart attack.CABG uses a vein from the legs,arm,chest or abdomen and forms a "bypass" over the blocked artery to restore blood flow to the heart which can prevent form further heart attacks.This surgery is usually performed with the heart stopped, necessitating the usage of cardiopulmonary bypass. However, recent advances allow the procedure to be performed with the heart beating and through smaller incisions.The first attempt to perform a CABG procedure was performed by Dr. Robert Goetz in 1960 in Albert Einstein College of Medicine, Bronx. But the first real successful procedure was performed in 1967 by Dr. Favaloro in the Cleveland Clinic by using a Saphenous Vein graft which is the most common method of performing the procedure today.
The decision to do a CABG procedure is made by the cardiologist,primary care doctor and the cardiac surgeon who jointly decide along with the patient whether it is beneficial to have a bypass procedure done or not.This decision is dependent on several factors like age,heart disease risk factors(cholesterol,smoking,hypertension, diabetes,arteries blocked) and current physical status of the patient.Approximately,448,000 cardiac CABG operations were done in the United States in 2006.
Terminology
CABG means Coronary Artery Bypass Graft.CAGS means Coronary Artery Graft surgery which is similar and should not be confused with Coronary Angiography.Similar Aortocoronary bypass (ACB) is also being used nowadays.[1]
The terms double bypass, triple bypass,quadruple bypass means only the number of arteries that are being bypassed or which are blocked in the heart.It does not imply to how sick a person is.That is totally dependent on the coronary angiogram which the doctor checks to see where are the blockages in the heart and makes the decision of bypass surgery accordingly.
Indications
Coronary Artery Bypass Graft surgery is usually performed for following conditions:
- Heart Attack (Stable Angina, Unstable Angina, Myocardial Infarction) .This is the most common and important reason for having a CABG procedure done and the reason for having Coronary Artery Bypass Graft depends upon the whole clinical status of the patient.
- To prevent future risk of heart attacks-Patients may be identified on having future risk of a heart attack depending on cardiac performance on Exercise test,Myocardial perfusion and blocked arteries on Coronary Angiography.
- After a heart attack-Patients may have CABG done if their heart attack was not relieved by Angioplasty or they are having a second heart attack.Again , the decision depends on the clinical status of the patient, picture of arteries on angiogram and cardiac risk factors.
The Coronary Artery Bypass Grafting Procedure (Simplified)
- The patient is brought to the operating room and moved onto the operating table.
- An anesthetist places a variety of intravenous lines, often including a pulmonary artery catheter and injects an induction agent (usually propofol) to render the patient unconscious and to anesthetize the patient.
- An endotracheal tube is inserted and secured by the anesthetist or a respiratory therapist and mechanical ventilation is started.
- The chest is opened via a median sternotomy and the heart is examined by the surgeon.
- The grafts are harvested - frequent conduits are the internal thoracic arteries, radial arteries and saphenous veins.
- The surgeon stops the heart and initiates cardiopulmonary bypass; or in the case of "off-pump" surgery, places devices to stabilize the heart.
- One end of each graft is sewn onto the coronary arteries beyond the blockages and the other end is attached to the aorta.
- The heart is restarted; or in "off-pump" surgery, the stabilizing devices are removed. In some cases, the aorta is partially occluded by a C shaped clamp, the heart is restarted and suturing of the grafts to the aorta is done in this partially occluded section of the aorta while the heart is beating. This reduces time spent on the heart lung machine.
- The sternum is wired together and the incisions are sutured closed.
- The patient is moved to the intensive care unit (ICU) to recover. After awakening and stabilizing in the ICU (approximately 1 day), the patient is transferred to the cardiac surgery unit until ready to go home (approximately 4 days)
Prognosis Following CABG
Prognosis following CABG depends on a variety of factors. Saphenous vein grafts remain open (patent) for approximately 8-15 years. In general, CABG improves the chances of survival of patients who are at high risk, such as those patients with left main disease. After approximately 5 years the difference in survival rate between those who have had surgery and those treated by drug therapy diminishes. Age at the time of CABG is critical to the prognosis, younger patients with no complicating diseases have a high probability of greater longevity.
Recovery after CABG
After the surgery, the patient spends 1-2 days in the ICU.Family members can meet the patient.The patient's heart rate, rhythm, blood pressure, pulse and breathing are monitored during this time.During the next 3-5 days,the breathing tube, tubes placed in chest to drain any accumulation of fluids,tube placed to drain bladder and other IV lines are slowly removed once the patient gets better.Patients are normally encouraged to walk 1-2 days after the procedure.It normally takes 3-6 weeks for complete recovery post-CABG.
Patient may complain of following things after bypass surgery is done
- Poor appetite and constipation
- Incision site on chest gets sore
- Swelling in the leg
- Decreased sleep after the procedure
- Depression
- Weakness of arms and legs
- Shortness of breath[2][3]
Complications after CABG
- Heart attack-A second heart attack can occur after CABG especially in high risk patients who had severe heart disease before.
- Heart Rhythm Disorders-Atrial Fibrillation and other heart rhtym disorders can occur after bypass operation.
- Pericarditis-Inflammation of the sac which covers the heart can occur which can also lead to chest pain.Also fluid accumulation can occur which is known as Pericardial Effusion.
- Neurological Complications like stroke,delirium,change in mental status and depression can occur.
- Bleeding post-operatively can occur and may cause massive blood transfusion.Also change in medication may be needed in consultation with the cardiologist and cardiac surgeon.
- Infections can occur at the incsion site on the chest and leg .Leg swelling can occur after the operation which may need surgical treatment.
- Kidney disease can develop in a small percentage of patients after bypass surgery
Self-Care
- Patient should have someone to look after the first 1-2 heals post-CABG
- Activity should be maintained but in consultation with the doctor
- Continue medications as prescribed
- Call doctor if having chest pain,cough, shortness of breath, dizziness, irregular pulse,changes in wound -color,becoming painful,changes in blood pressure, weight changes,increased temperature, headaches or difficulty in taking medications.
Guidelines and recommendations can be found at following links:
http://www.nlm.nih.gov/medlineplus/
http://www.americanheart.org/
http://www.sts.org/