Coronary Angiography – An invasive radiographic imaging method of the coronary arteries of the heart after selective intracoronary injection of a radiopaque contrast medium. Angiography can be performed for all the blood vessels in the body. The vessels of the eyes, brain, heart, and legs are typically the most studied vascular systems.
Conditions for which cardiac catheterization is used for diagnosis and treatment:
• Diseases of the coronary arteries, heart valves, or aorta.
• Assessment of myocardial activity.
• Determination of advanced treatment methods such as coronary balloon angioplasty and stenting, coronary artery bypass grafting (CABG), invasive or surgical interventions on heart valves.
How is coronary angiography performed?
During coronary angiography, a thin, flexible plastic introducer is placed into an artery in the groin or arm. Through this introducer, soft and thin hollow plastic catheters are advanced toward the coronary arteries. The catheter is directed into the coronary arteries using a special X-ray machine.
Contrast dye (angiographic dye) is injected through the catheter, and moving X-ray images are recorded digitally. This part of the procedure is called coronary angiography. In addition to these images, in some special cases, advanced imaging and evaluation methods such as intravascular ultrasound (IVUS), optical coherence tomography (OCT), or fractional flow reserve (FFR) measurements may be required.
What is an invasive coronary procedure?
An invasive coronary procedure is a non-surgical treatment for opening narrowed coronary arteries to increase blood flow to the heart. If narrowed or blocked coronary arteries are detected during coronary angiography, they may be treated with angioplasty and stenting in a single session or in a planned separate session, depending on the joint decision of the physician and patient. The decision may vary based on the patient's clinical condition. The coronary invasive procedure begins the same way as coronary angiography. Balloon angioplasty and stenting are performed to open the coronary arteries after the catheter is positioned at the coronary artery outlet.
What is balloon angioplasty?
A liquid at the tip of a thin catheter is used to inflate an expandable balloon to open a narrowed heart vessel. Balloon angioplasty is technically called percutaneous coronary angioplasty (PCTA) or percutaneous coronary intervention (PCI). When the balloon is inflated, the fatty plaque is pressed against the blocked artery walls, and blood flow is restored.
How is balloon angioplasty performed?
In most cases, stent placement is performed in combination with balloon angioplasty. A stent is a small metal mesh tube that acts as a scaffold to support the coronary artery. A balloon catheter, advanced over a guidewire, is used to position the stent into the narrowed artery. When the stent reaches the narrowed area, the balloon is inflated, causing the stent to expand according to the artery’s diameter and adhere to the vessel wall. After the balloon is deflated, the stent remains in place. Over several weeks, the stent is covered with normal vascular cells (endothelium). Stent angioplasty is typically used for patients with narrowing or blockage in 1-2 coronary arteries. If more than two coronary arteries are blocked, coronary artery bypass grafting may be considered.
Does chest pain always warrant angiography?
Complaints of chest pain or shortness of breath are not always of cardiac origin. Most chest pains in individuals are not heart-related. Such a patient should be thoroughly examined, with careful attention to their complaints and a detailed review of cardiovascular risk factors. If coronary artery narrowing is suspected following a detailed examination and several tests (e.g., stress test, electrocardiogram, echocardiography), angiography should be performed. Only a cardiologist can determine whether it is necessary or not.
Not every narrowed artery can be stented. The main coronary arteries supplying the heart are vessels with diameters of 2-4 mm. Smaller vessels gradually thin (i.e., decrease in diameter), resembling branches of a tree. Stents are generally not placed in vessels that are less than 2 mm in diameter and narrowed on angiography because these thin vessels are more likely to block again within a few months of stent placement. As the heart tissue supplied by these smaller vessels is limited, the blockage of these vessels does not pose a major problem. Therefore, for the narrowing of these small vessels, medication therapy is preferred over stenting.
What is the difference between a drug-eluting and a non-drug-eluting (bare-metal) stent?
A stent is a cylindrical mesh tube with two open ends, made of special metals or polymers. Drug-eluting stents are coated with drugs that suppress cell proliferation compared to bare-metal stents. These drugs reduce the likelihood of stent restenosis (narrowing) in the medium and long term after implantation. Drug-eluting stents are less likely to become blocked than bare-metal stents, which is why they are more commonly used to open narrowed heart vessels. However, drug-eluting stents are more expensive than bare-metal stents.
Stenting or bypass surgery?
The decision regarding which treatment method to use depends on the degree of narrowing of the patient's coronary vessels and their overall health. If one or two of the three coronary arteries that supply the heart are narrowed and can be opened with a stent, stenting is recommended first. If there is significant narrowing in all three coronary arteries or the left main coronary artery, coronary artery bypass grafting (CABG) surgery should be considered. This is because such patients may benefit more from bypass surgery, but this is not always the case.
Is there a guarantee that the stented artery will not become blocked again?
No doctor can guarantee that a stented artery will not become blocked again, whether the stent is drug-eluting or not. Generally, if the stent does not become blocked within the first year after placement, the likelihood of subsequent blockages is lower. However, the problem does not disappear after the stent is placed. Stent blockage can occur due to several factors, including smoking (or resuming smoking), uncontrolled blood sugar levels in diabetic patients, or uncontrolled hypertension over time. Another factor is stress.
Should medication be stopped after stent placement?
Even after stenting or bypass surgery, patients must take prescribed medications for life. We address the narrowing or blockage, but it's essential to continue medication to prevent further blockages in other parts of the stent or vessel.
Can a blocked stent be replaced with a new one?
Once a stent is implanted, it cannot be removed or replaced. Stents do not wear out but can become blocked. If an implanted stent becomes blocked, the inner part of the stent can be cleared with special balloons, or no intervention may be performed, or bypass surgery may be recommended, which is another treatment method considering narrowing in other vessels.
Should all patients undergo follow-up angiography after stenting or bypass surgery?
Patients who have undergone stenting or bypass surgery should undergo regular follow-ups for a certain period, even if they do not have complaints. However, patients without complaints and issues in follow-up exams or tests (e.g., stress test, electrocardiogram, echocardiography) do not necessarily need repeat angiography, even after several years.
At OKI Hospital, angiography is performed by experienced doctors using state-of-the-art equipment. Our specialists are available to assist you 24 hours a day, 7 days a week.
OKI Hospital serves both private patients and those covered by Mandatory Health Insurance and Voluntary Health Insurance.