Coronary revascularization

Overview

Coronary revascularization encompasses a range of medical interventions aimed at reinstating adequate blood flow to areas of the heart experiencing ischemia, a condition where blood supply is insufficient to meet the heart’s demands. These interventions serve to address the aftermath of a heart attack or to proactively prevent heart attacks in individuals at elevated risk.

Coronary revascularization generally involves two distinct approaches:

• Percutaneous coronary intervention (PCI): This is a minimally-invasive procedure designed to restore blood flow by addressing blockages from the inside of the arteries.
• Coronary artery bypass grafting (CABG): This surgical procedure involves the creation of a bypass route around a blocked segment of a coronary artery to facilitate improved blood circulation.

Reasons for undergoing the procedure

Coronary revascularization is a vital procedure with the potential to benefit individuals suffering from restricted blood flow to specific regions of their heart, primarily caused by coronary artery disease, which becomes more prevalent as people age and are exposed to certain risk factors. This condition, closely associated with aging, results from atherosclerosis, the gradual accumulation of plaque, a fatty substance, within the heart’s arteries, akin to grease buildup in a clogged drainpipe. If a segment of this plaque ruptures, it can trigger the formation of a blood clot, ultimately leading to partial or complete artery blockage and ensuing ischemia—a condition characterized by cellular damage due to insufficient blood supply. Ischemia in the heart muscle poses a significant threat, as the resulting cell damage is irreversible, making timely restoration of blood flow imperative to mitigate or prevent permanent harm.

Any condition associated with acute coronary syndrome might result in heart ischemia. These consist of:

• Stable angina
• Unstable angina
• Heart attack

Risks

The risks of coronary revascularization depend strongly on the procedure itself. The general risks are as follows:

• Percutaneous coronary intervention (PCI): The risks mostly include damage to your heart or nearby blood vessels from the inside. This can cause irregular heart rhythms (arrhythmias), blood clots, stroke, or bleeding.
• Coronary artery bypass grafting (CABG): Surgery has additional risks, especially pain, bleeding, and a chance of infection.

Overall, the risks and complications depend not only on the procedure but also on your health. That includes any other conditions you might have, your age, medical history, and personal circumstances. Your healthcare provider is the best person to tell you about what to expect with this procedure, especially the risks and possible complications.

Before the procedure

Before you undergo any coronary revascularization procedure, you will likely undergo several medical tests that will help healthcare providers plan the best ways to treat your condition. These tests can include, but are not limited to, one or more of the following:

• Electrocardiogram (ECG) or Electrocardiography.
• Echocardiogram.
• Cardiac catheterization.
• X-ray angiography or Computed Tomography (CT) scan angiography.
• Coronary calcium scan.
• Complete blood count.
• Cardiac enzyme tests.

If you are having a coronary revascularization procedure in a nonemergency situation, your healthcare provider will also instruct you to fast before it starts. This typically involves abstaining from all foods except clear liquids for at least eight hours before the procedure and refraining from all liquids for at least two hours before.

Right before the procedure begins, a healthcare provider will also insert an intravenous (IV) line into one of your veins, usually in one of your arms. IV lines enable providers to administer fluids and medications quickly and easily. For percutaneous coronary intervention (PCI), you will likely receive a sedative medication to help you relax. For coronary artery bypass grafting (CABG), you will receive general anesthesia, which will induce a deep sleep throughout the procedure.

During the procedure

Percutaneous coronary intervention (PCI)

Percutaneous Coronary Intervention (PCI) is a medical procedure that involves inserting a catheter (a hollow, tube-like device) into a major blood vessel in your body, typically in your wrist or upper thigh. Once the catheter is in place, a healthcare provider guides it to your heart and uses various tools and methods to restore blood flow. They may also inject a special contrast dye to enhance visibility on X-ray imaging for precise localization of blockages.

Depending on your condition, the provider may use one or both of the following tools and techniques:

• Balloon angioplasty: This technique uses a balloon attached to the catheter’s tip. After positioning the catheter at the site of the blocked or narrowed artery, the balloon is inflated to widen the artery.
• Stenting: Stenting involves placing a stent, a supportive framework, to keep the narrowed section of the artery open. Stents can be made of bare metal or have a medication-coated surface that gradually releases medicine to prevent further narrowing around the stent.
• Brachytherapy: Brachytherapy involves delivering radiation from within the blood vessels to prevent the recurrence of stenosis (narrowing) after procedures like stenting. While brachytherapy is primarily used in cancer treatment, it can also prevent vascular stenosis.

After widening the artery (and possibly placing a stent), the provider removes the catheter and closes the access site with stitches to complete the procedure.

Coronary artery bypass grafting (CABG)

Coronary Artery Bypass Grafting (CABG) is a surgical procedure that restores blood flow to the heart. The procedure starts with the surgeon identifying and harvesting a blood vessel from another part of your body, such as a leg, arm, or back. The surgeon then accesses the heart through one of two methods:

• Open surgery: Open surgery involves a chest incision, usually several inches long, down the center of the chest. This incision allows the surgeon to open the chest cavity by splitting the sternum (breastbone) and separating the rib cage, providing direct access to the heart.
• Minimally-invasive and/or robot-assisted surgery: In this method, one or more small incisions are made, allowing the surgeon to access the heart using specialized surgical instruments through the spaces between the ribs. Robotic surgery employs robotic arms controlled by the surgeon, along with a small robotic camera, to perform the procedure.

Depending on the chosen method, the surgeon may temporarily stop your heart and use a heart-lung bypass machine to oxygenate your blood and maintain circulation. However, some patients may undergo off-pump bypass surgery, where the heart continues to beat.

Once access to the heart is established, the surgeon uses the harvested blood vessel to create a bypass around the blocked section of the artery. This bypass restores or maintains blood flow to areas of the heart with restricted or no blood supply.

After completing the bypass, the surgeon closes the chest and, if the heart was stopped, restarts it. In open surgery, the ribs are realigned, and the sternum is wired together for healing before closing the incision. In minimally-invasive or robot-assisted procedures, the instruments are withdrawn through the smaller incisions, which are then stitched closed.

Specialized Approaches

Additional techniques may be employed alongside the procedures mentioned above or as standalone options to enhance the chances of a successful revascularization procedure. These include:

• Total arterial revascularization: This approach involves using an artery, rather than a vein, as the bypass vessel. Arteries tend to provide better durability and are less prone to complications compared to vein-based grafts.
• Transmyocardial revascularization (TMR): TMR involves directing a specific type of laser into the heart muscle. This laser improves blood flow to affected areas of the heart muscle and stimulates the formation of new blood vessels. TMR may be considered when other procedures are not viable or have proven ineffective. It is sometimes used in conjunction with CABG to improve overall success.

After the procedure

After undergoing the procedure, your recovery period varies based on the nature of the procedure, your overall health, and whether it was performed as an emergency. Generally, better health results in a shorter hospital stay and a smoother recovery. During this phase, your healthcare provider may recommend cardiac rehabilitation, staffed by a team of experts including doctors, nurses, exercise physiologists, nutritionists, and more. They will guide you in exercise and heart care to improve your condition and ensure you regain the strength and knowledge needed for your daily routine post-coronary revascularization. Scheduled follow-up appointments and tests will monitor your heart’s function, and adhering to your provider’s advice regarding diet, exercise, and medications is crucial. Don’t hesitate to ask questions to better understand your care and enhance your well-being.

Outcome

In general, percutaneous coronary intervention (PCI) has much shorter recovery times because it isn’t major surgery. PCI is sometimes an outpatient procedure, especially in nonemergency situations, and recovery usually takes days. The hospital stay for coronary artery bypass grafting (CABG) may be several days, and recovery can take weeks or even months. Your healthcare provider is the best person to tell you how long your recovery should take, what to expect, and how you can help yourself along the road to recovery.

After a coronary revascularization procedure, your healthcare provider can provide guidance regarding potential signs and symptoms that may serve as early warnings of potential issues. In broad terms, the symptoms to remain vigilant for are those typically associated with a heart attack or similar conditions. These include:

• Chest pain (referred to as angina).
• Shortness of breath (referred to as dyspnea).
• Dizziness or a sensation of lightheadedness.
• Fainting or loss of consciousness.