Cardiovascular surgery . It is a surgical- type medical specialty that, by using the hand and the instrument, aims to solve or improve heart diseases that are not treatable with drugs, or with minor interventions such as catheterizations, stents, etc. In most cases, the objective is to decrease the magnitude of the symptoms and improve the patient’s quality of life, since complete resolution of the problem is atypical.
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- 1 History in synthesis
- 2 Extracorporeal circulation machine
- 3 Cooling techniques
- 1 The heart can cool in two ways:
- 4 Personnel who are in the operating room during the intervention
- 5 Types of cardiac and vascular interventions
- 1 Coronary bypass
- 2 Valve repair or replacement
- 3 Antiarrhythmic surgery
- 4 Aneurysm repair
- 5 Transmyocardial laser revascularization (RTML)
- 6 Carotid endarterectomy
- 7 Heart transplant
- 6 Virtual three-dimensional model
- 7 Sources
History in synthesis
Years ago, many doctors thought that cardiovascular surgery was a dream. During World War II , surgeons had learned to operate on the heart but were unable to put what they learned into practice because it was difficult to operate on a beating and moving heart. Furthermore, it was not possible to stop the heart for more than a few minutes without causing brain damage.
Two important advances in medicine made cardiovascular surgery possible :
- The extracorporeal circulation machine, which takes over the functions of the heart.
- Body cooling techniques, which allow the intervention time to be prolonged without causing brain damage.
Extracorporeal circulation machine
The extracorporeal circulation machine is also called a cardiopulmonary bypass machine. It assumes the functions of the heart by taking care of the pumping action and oxygenating the blood. In this way, the heart remains immobile during the operation, which is necessary to open the heart (open heart surgery). Because the extracorporeal circulation machine takes over the functions of the heart , surgeons can operate on a heart that neither moves nor is full of blood .
When the patient is connected to an extracorporeal circulation machine, it performs the same functions that the heart and lungs would do. The machine transports blood from the upper right chamber of the heart (the right atrium) to a special container called an “oxygenator.” Inside the oxygenator, oxygen bubbles mix with the blood and enter the red blood cells . This causes the blood to change from dark red (poor in oxygen) to bright red (rich in oxygen). Next, a filter removes air bubbles from the oxygen-rich blood, and the blood passes through a plastic tube to the body’s main blood line (the aorta). From the aorta, blood reaches the rest of the body.
The extracorporeal circulation machine can supply the functions of the heart and lungs for several hours. Trained technicians called “perfusionists” (blood flow specialists) make sure that the machine works correctly during surgery. Still, surgeons try to limit the time patients stay connected to the machine .
Cooling techniques allow the heart to be stopped for long periods without damaging the heart tissue. Low temperatures prevent heart tissue damage because they reduce the heart’s need for oxygen.
The heart can cool in two ways:
- The blood cools as it passes through the extracorporeal circulation machine. In turn, this cooled blood reduces body temperature as it enters the body .
- Bathe the heart in cold salty water (saline).
When the heart has cooled it slows down and stops. Injecting a special solution of potassium into the heart can speed up this process and stop the heart completely. In this way, the heart tissue is generally undamaged for about 2 to 4 hours.
Personnel who are in the operating room during the intervention
During cardiac surgery, a highly trained group works as a team. The following is a list of people who are in the operating room during cardiac surgery.
- The cardiovascular surgeon, who leads the surgical team and performs the key parts of the intervention.
- Assistant surgeons, who follow the instructions of the cardiovascular surgeon.
- The cardiovascular anesthesiologist, who administers medications that sleep the patient during the intervention (anesthesia). The anesthesiologist ensures that the patient receives the appropriate amount of medication during surgery and is responsible for monitoring the respirator, which is the device that replaces the patient’s breathing during the operation.
- The perfusionist, who operates the extracorporeal circulation machine.
Types of cardiac and vascular interventions
Today, many different interventions of the heart and blood vessels are performed .
This is the most common cardiac intervention. It is also called a graft aortocoronary bypass, aortocoronary bypass, aortocoronary bypass, surgical revascularization, or bypass surgery.
The operation involves sewing a section of a vein in the leg or an artery in the chest or other part of the body to circumvent a section of a damaged coronary artery . The procedure creates a new route for blood to pass, so that the heart muscle can receive the oxygen-rich blood it needs to function properly.
During a bypass procedure, the sternum is divided, the heart is stopped, and blood is diverted to an extracorporeal circulation machine. Unlike other types of cardiac procedures, the heart chambers are not opened during a bypass procedure.
When we talk about a single, double, triple or quadruple bypass, we are referring to the number of arteries that are circumvented. The number of referrals does not necessarily indicate the severity of cardiovascular disease.
Valve repair or replacement
The heart pumps the blood in one direction only. The heart valves play a key role in this way blood flow to the opened and closed with each heartbeat. Pressure changes behind and in front of the valves allow them to open their flap-like “gates” (called “leaflets”) precisely at the right time, and then close them tightly to prevent backflow of blood.
Two of the most common valve problems that require surgical intervention are:
- Stenosis, which means the leaflets don’t open enough and only a small amount of blood can pass through the valve. Stenosis occurs when the leaflets thicken, harden, or fuse. Surgery is required to open the existing valve or replace it with a new one.
- Regurgitation, which is also called “insufficiency” or “incompetence,” means that the valve does not close properly and allows retrograde blood leakage to occur instead of the blood flowing accordingly. Surgery is required to adjust or replace the valve.
Surgical valve repair involves rebuilding the valve by a surgeon to make it work properly. Valve replacement involves replacing an existing valve with a biological valve (made of animal or human tissue) or a mechanical valve (made of materials such as plastic, carbon, or metal).
Any irregularity in the heart’s natural rhythm is called “arrhythmia.” Arrhythmias are typically treated first with medications. Other treatments may include
- Electrical cardioversion, which is when the cardiologist or surgeon uses paddles to deliver an electrical shock to the heart to normalize the heart rhythm.
- Catheter ablation, which is when the cardiologist uses a special instrument to destroy the cells that cause the arrhythmia. The procedure is performed in the cardiac catheterization laboratory.
- Pacing and rhythm control devices, such as pacemakers and implantable cardioverter defibrillators (ICDs). These devices can be implanted in the operating room or catheterization laboratory.
When these treatments are not effective, surgical intervention may be necessary. One type of antiarrhythmic intervention is Cox surgery (labyrinth technique). In this procedure, surgeons create a “maze” of new pathways for electrical conduction so that electrical impulses can easily travel through the heart. Cox surgery is typically used to treat a type of arrhythmia called “atrial fibrillation.” Atrial fibrillation is the most common type of arrhythmia.
An aneurysm is a balloon-like dilation that occurs in a blood vessel or the wall of the heart. An aneurysm occurs when a wall of a blood vessel or heart weakens. The pressure of the blood pushes the wall out and forms what could be described as a blister. Aneurysms can often be repaired before they rupture.
Surgery to repair them involves replacing the weakened section of the blood vessel or heart with a synthetic patch or tube (a graft).
Aneurysms in the heart wall typically occur in the lower left cavity (left ventricle). These aneurysms are called “left ventricular aneurysms” and can form after a heart attack. (A heart attack can weaken the wall of the left ventricle.) If a left ventricular aneurysm causes an irregular heartbeat or heart failure, an open-heart procedure may need to be done to remove the damaged part of the wall.
Transmyocardial laser revascularization (RTML)
Angina pectoris is pain that occurs when one of the heart’s blood vessels (called “coronary arteries”) becomes damaged and cannot supply enough blood to part of the heart to meet its need for oxygen. The poor supply of oxygen-rich blood to the heart is called “ischemia.” Angina usually occurs when the heart has an increased need for oxygen-rich blood, for example, during physical exercise. Angina is almost always caused by coronary artery disease (CAD).
Transmyocardial laser revascularization (RTML) is a procedure that involves using a laser to create small channels in the heart muscle so that blood passes directly to the heart muscle from one of the chambers of the heart. By increasing blood flow , the heart receives more oxygen . This procedure is only done as a last resort. For example, it could be done in patients who have undergone many coronary bypass procedures and cannot undergo another.
Carotid artery disease is a disease that affects the blood vessels that lead to the head and brain. Like the heart, brain cells need a constant supply of oxygen-rich blood. This blood reaches the brain through the two large carotid arteries located at the front of the neck and the two smaller vertebral arteries located at the back of the neck. The right and left vertebral arteries join at the base of the brain and form the so-called basilar artery . A stroke (or stroke) most commonly occurs when the fatty plaque clogs the carotid arteries and the brain doesn’t get enough oxygen.
Carotid endarterectomy is the most common surgical treatment for carotid artery disease. An incision is first made in the neck where the obstruction is located. A tube is then inserted above and below the obstruction to divert blood flow so that the carotid artery can be opened and cleaned.
Carotid endarterectomy can also be performed using a technique with which it is not necessary to bypass blood flow. This procedure stops the flow of blood just long enough to clean the artery.
The first heart transplants were performed towards the end of the 1960s. But it was not until antirejection drugs (immunosuppressants) began to be used in the 1980s that the procedure became an accepted operation. Today, heart transplants give hope to a group of patients who would otherwise die of heart failure.
The need for a heart transplant may be due to one of several cardiovascular problems that damage the heart muscle. The two most common cardiovascular problems are idiopathic cardiomyopathy (heart muscle disease of unknown origin) and coronary artery disease (plaque buildup in the arteries of the heart).
As cardiovascular disease worsens, the heart weakens and loses the ability to pump oxygen-rich blood to the rest of the body. Since the heart must try harder to pump blood to the body, it tries to compensate by increasing in size (hypertrophy). Over time, the heart tries so hard to pump the blood that it can simply wear out due to disease and not be able to meet even the smallest blood needs of the body. Sometimes medications, cardiac assist devices, and other treatments can help and even improve a patient’s health. But when these treatments are not effective, transplantation is the only option.
Cardiovascular nurses, who have received special training to help during cardiac surgery.
Three-dimensional virtual model
The French company Dassault Systèmes has completed the development of the first three-dimensional virtual model of a complete human heart, which captures its electrical and mechanical behavior , which can be used in the diagnosis, treatment and prevention of heart disease and in the manufacture of devices doctors.
The finding is part of the ‘Living Heart’ project and for its creation they have used the ‘Simulia’ system, a realistic simulation software that is used in design, engineering and research processes and that has allowed capturing the electrical and mechanical behavior of the heart in full detail.
Cardiovascular surgery team
Using echocardiogram, MRI and CT scanner images, along with cardiac research data, personalized 3D heart simulations will allow “very soon” for medical professionals “to better understand a patient’s heart behavior without the need for additional invasive diagnostic procedures, “the researchers say.
“It is exciting how you can simulate the way in which a patient’s heart can respond to a wide variety of interventions, thus avoiding uncertainties about the result of a specific treatment,” said James Perry, director of Electrophysiology and Coronary Diseases Rady from San Diego (USA) ], who has collaborated on the project.
For this expert, the advance will be useful to improve therapies for patients with congenital heart defects, which require many treatments, but will also be applicable to a large percentage of the population suffering from heart failure, arrhythmias and other structural abnormalities.
“This technology will represent a breakthrough that will accelerate the materialization of our scientific advances in cardiac function in practical applications that promote better health and safety” This virtual heart is part of the ‘Living Heart’ project, launched last January , which brings together leading cardiovascular researchers and educators, heart device manufacturers, and regulatory agencies.
According to participants, this realistic simulation of a human heart will not only be a valuable educational tool and fostering innovation in research, but it will also speed up regulatory approval cycles, reduce development costs for new, more personalized devices, and enable early diagnosis and improvement of treatment results.