An angiogram and angioplasty are two distinct procedures used in cardiovascular care, despite their similar names. An angiogram is a diagnostic tool used to visualize blood vessels and identify problems. In contrast, an angioplasty is an interventional, therapeutic procedure designed to treat those problems. Both are minimally invasive procedures typically performed in a hospital’s catheterization laboratory to address blockages caused by coronary artery disease.
The Angiogram: A Diagnostic Tool
The angiogram is a specialized X-ray imaging procedure that maps the body’s blood vessels, particularly the coronary arteries. Its purpose is to locate narrowing, obstruction, or abnormalities caused by plaque buildup in Coronary Artery Disease (CAD). The procedure begins with the insertion of a thin, flexible catheter into an artery, usually in the wrist or groin.
The catheter is guided through the vascular system toward the area of interest. Once positioned, a contrast agent, typically iodine-based, is injected through the catheter. This agent fills the blood vessels, making them temporarily visible under fluoroscopy, a real-time X-ray imaging technique.
The healthcare team observes the contrast agent’s flow through the arteries on a monitor. Blockages or restrictions caused by plaque appear as areas where the dye flow is slowed or stopped, allowing for precise determination of the disease’s location and severity. This diagnostic information is then used to plan the appropriate course of treatment.
The Angioplasty: An Interventional Treatment
In contrast to the angiogram, angioplasty is a procedure focused on actively restoring proper blood flow through a narrowed or blocked artery. This therapeutic intervention is often referred to as Percutaneous Coronary Intervention (PCI) when performed on the arteries of the heart. The goal of angioplasty is to physically compress the atherosclerotic plaque against the artery wall, thereby widening the vessel’s internal diameter.
The angioplasty procedure utilizes the same entry points and catheter-based approach as the angiogram, with a specialized catheter being threaded to the site of the blockage. This catheter is equipped with a small, inflatable balloon at its tip, known as a balloon catheter. Once the balloon catheter is positioned precisely within the narrowed segment, the balloon is inflated to a high pressure for a brief period.
Inflation of the balloon physically pushes the obstructing plaque outward, which restores the vessel’s patency and improves blood flow to the heart muscle. Following the initial widening, the procedure often includes stent placement to maintain the newly opened vessel. A stent is a small, mesh tube that is mounted onto the balloon catheter, expanded simultaneously with the final balloon inflation, and then left in place to act as a scaffold. Stents are frequently coated with medication, known as drug-eluting stents, to help prevent the artery from narrowing again, a process called restenosis.
The Sequential Relationship Between Procedures
The difference between the two procedures dictates their clinical sequence, as the diagnostic step must precede the therapeutic one. An angiogram is performed first to gain visual confirmation of a blockage, its exact location, and its severity. This information is required before any treatment can be planned. The resulting image from the angiogram guides the physician’s decision to proceed with an angioplasty or consider other options.
A treatment, such as angioplasty, cannot be performed effectively without the precise mapping and assessment provided by the initial diagnostic angiogram. In many cases, if a significant and treatable blockage is identified during the angiogram, the physician may elect to proceed immediately to angioplasty during the same session. However, the angiogram may also reveal that the blockages are too widespread, numerous, or complex for a catheter-based intervention.
When the disease is particularly extensive, the diagnostic results might instead lead to a recommendation for a more involved surgical treatment, such as Coronary Artery Bypass Grafting (CABG) surgery. The angiogram serves as the informational precursor, determining if, where, and how an angioplasty or another form of revascularization is required.