Caused by arteriosclerosis, ischemic heart disease prevents the heart from receiving the necessary blood. It is usually asymptomatic and can be prevented. When it produces symptoms, it does so as recurrent and oppressive pain in the sternum area and generally after physical exercise or emotions. In addition to the symptoms, the diagnosis is supported by the electrocardiogram, the stress test and finally the cardiac catheterization.
Treatment includes hygienic-dietary measures, drugs, coronary angioplasty, and coronary artery bypass surgery or "aorto-coronary bypass."
For patients with coronary artery disease that includes three or more affected vessels, diabetic patients with involvement of the internal mammary artery and some other vessel, involvement of the main trunk of the left coronary artery or in cases where coronary angioplasty is not possible (vascular tortuosity, bifurcation areas, very long lesions, generalized disease ...), coronary bypass surgery is indicated.
What is a bypass?
Aortocoronary bypass (also called aortocoronary bypass with graft, aortocoronary bypass, aortocoronary bypass, surgical revascularization or bypass intervention is the most common cardiac intervention.
The operation consists of suturing a vein in the leg or an artery in the chest to the heart in order to bypass the blocked area. Thus, a new path is created by which blood can reach the affected heart muscle and thus contract (beat) correctly.
During the procedure, it is not necessary to open the heart chambers, since the coronary arteries run along the surface of the heart.
When we talk about a single, double, triple or quadruple bypass, we refer to the number of arteries that are bypassed. The number of referrals does not necessarily indicate the severity of cardiovascular disease.
Who is in the operating room during the intervention?
During a cardiac intervention, a highly trained group works as a team. The following is a list of the people who are in the operating room during a heart procedure.
The cardiovascular surgeon, who leads the surgical team and performs the intervention.
The assistant cardiovascular surgeons.
The cardiovascular anesthesiologist, who administers the medications that make the patient sleep during the intervention (anesthesia). It ensures that the patient receives the correct amount of drug during surgery and is in charge of controlling the monitors that monitor the patient's condition during the operation.
The perfusionist, who controls the heart-lung machine.
Cardiovascular nurses, who have received specific training to help during a cardiac intervention.
What is the cardiopulmonary bypass machine?
The cardiopulmonary bypass machine is also called a heart-lung machine or cardiopulmonary bypass machine as it performs the main functions of both the heart and the lung: pumping and oxygenate the blood. Thus, it is possible to operate on the heart by opening its cavities and finding them immobile and empty of blood.
Blood is transported from the right atrium or vena cavae of the heart to the reservoir of the machine, from where it passes through an oxygenator where oxygen-poor blood mixes with bubbles of this gas that are introduced into the red blood cells. The oxygenated blood ("red blood") passes through a filter that eliminates air bubbles and is returned to the heart through a cannula located in the aorta, the main artery of the body. From there it is distributed to the rest of the body, reaching the right atrium again through the vena cavae and repeating the cycle for as long as necessary until the end of the intervention. Perfusionists are specialized technicians in the management of the extracorporeal pump, ensuring its correct operation during the intervention.
Before the intervention
Except in urgent cases, the intervention will be carried out on a date suitable for you and with the availability of an operating room by the surgeon. You should inform him of your recent health status including if you have had a cold, tooth decay, or fever. Remember to bring the medications you are taking or have taken in recent days to the Hospital. You will probably enter the day before or the morning of the intervention.
You will need to bathe with an antiseptic solution and the area near the surgical field will be shaved. With this we avoid future infections. You will be fasting from midnight before the intervention, in order not to suffer anesthetic complications. For this same reason, it is advisable that in case of smoking, do not do so for at least two weeks prior to the intervention.
After admission, an electrocardiogram, a blood test and a chest X-ray will be performed (if not already done).
As part of your pre-anesthetic medication, you will likely be given a sedative to help you relax before going to the operating room. Once in the operating room, you will be given a route through which to administer anesthetic drugs. You probably do not remember this after the intervention.
During the intervention
Once you are asleep, a series of tubes and probes will be inserted:
Endotracheal tube: allows connection to a respirator during surgery
Nasogastric tube: it is inserted through the nose and reaches the stomach, so that fluids and air do not accumulate and you do not suffer nausea or vomiting when you wake up.
Bladder catheter: it is introduced through the urethra and reaches the urinary bladder, which allows urine to be collected during the intervention, preventing the bladder from filling up and making it possible to know the functioning of the kidneys.
During the procedure, you will be given heparin, an anticoagulant that prevents the blood from clotting while you are having surgery. Before ending the intervention, an "antidote" is administered, protamine, which reverses this action.
It may be necessary to remove a piece of a vein in the leg (internal saphenous vein) to be used as a vein graft. An artery running through the chest (internal mammary artery) will almost certainly be removed to be used as an arterial graft.
You will be left between 1 and 3 drainage tubes, which serve to evacuate the normal initial bleeding that occurs after the intervention. Cardiac surgery can lead to increased initial excitability of the heart tissue, so you will be implanted between 1 and 5 epicardial pacemaker electrodes, connected to the heart and protruding from the lower edge of the ribs. These electrodes allow the placement of a temporary pacemaker in case of rhythm disturbances during the initial postoperative period.
The operation can last between 2 and 6 hours on average, depending on the number of grafts that are needed. A longer duration of the intervention does not necessarily imply greater severity or difficulty.
Initially, you will be admitted to the intensive care unit (ICU) where you will wake up between 3 and 9 hours after the end of the operation. When you are able to breathe on your own, the endotracheal tube will be removed. When the drainage tubes stop draining (generally the next day) they will be removed and after 24-72 hours on average, they will be discharged to the plant, where they will remain between 3 and 7 days on average.
What is off-pump surgery?
Off-pump coronary artery surgery (also called off-pump, off-pump, or no CPB) is the performance of coronary artery bypass grafting without the use of a cardiopulmonary bypass pump.
How is surgery performed without a heart-lung machine?
The preparation is the same as a patient who is going to undergo open heart surgery with a cardiopulmonary bypass pump; You will only need more hydration, a little more serum than is normally required in heart-lung machine surgery.
What benefits can come from off-pump surgery?
The off-pump procedure allows you to:
Avoid making a hole in the ascending aorta to introduce a cannula through which the blood from the pump returns.
Avoid making another hole in the heart at the level of the right atrium where we insert the cannula that will suck all the blood that was going to reach the heart to send it to be oxygenated.
Avoid lowering the patient's temperature.
Avoid using an oxygenator and haemoconcentrators.
There is no need for an electric shock because the heart did not stop.
There is no need to rewarm the patient since they never got cold.
There is no need for the use of some medications known as inotropics, which cause the heart to contract harder, because you may be "groggy" after standing for half an hour or an hour while using the heart-lung machine.
The extracorporeal circulation pump damages the cells that pass into the machine. When not used, there is no hemolysis (death of these cells) and there is less anemia, postoperative bleeding is less and this implies less need for blood transfusions that can translate into a lower risk of contracting an infection.
Decrease recovery time, hospitalization time is shorter, patient recovery requires less medication, patients walk out of the hospital in half the time, 3 to 5 days instead of 8 or 10 that are required when using the extracorporeal circulation pump.
What characteristics must a patient meet to be a candidate for off-pump surgery?
Your surgeon will indicate to you, evaluating the anatomy of the affected vessels and the associated diseases that you present, whether or not you are a candidate for off-pump surgery.
When there are two or more vessels on the back face of the heart, which we call the posterior, inferior face of the heart, it is probably more comfortable to do it at a stopped heart. If the patient is young and has not had heart attacks, it can be done with a stopped heart with very similar results. However, in very deteriorated patients, who have for example damaged kidney or lungs, it is convenient to try to spare them the damage suffered by the kidney or lung, when the patient is on the extracorporeal circulation pump. In those cases, it is worth doing the surgery or trying to do it with a beating heart, without stopping the heart and without using the extracorporeal circulation pump.
There are certain situations during surgery (hypotension, arrhythmias ...) that make it advisable to reconvert surgery without a pump to traditional surgery. In that case, your surgeon will judiciously assess each specific case and decide the best option.
Life after bypass
After this intervention, you should reduce the consumption of animal fats and cholesterol. You can walk or swim slowly and a cardiac rehabilitation program that includes a specific balanced diet, smoking cessation and stress management would be appropriate.
In addition, you must continue taking drugs that prevent the progression of the disease and limit the work that the heart must do. This reduces oxygen consumption and therefore prevents the appearance of angina. You will also need to take an antiplatelet drug and a cholesterol-lowering drug (statin), unless you are allergic to them.
In 4 to 6 weeks you will be able to return to an office job. In case your job requires physical exercise or significant stress, this time may be extended or even require a leave or change of employment in extreme cases.