When a coronary artery becomes significantly narrowed, the heart muscle may not receive enough blood to meet its oxygen requirements. Depending on the location and severity of the narrowing, treatment may involve medication, coronary angioplasty and stenting, or coronary artery bypass surgery.
Angioplasty and stenting are forms of percutaneous coronary intervention (PCI). Instead of opening the chest to create a bypass around a blocked artery, PCI uses a catheter introduced through an artery to reach the coronary circulation and treat the narrowed segment from inside the vessel.
The important question is not simply whether a coronary artery is narrowed. It is whether the narrowing is clinically significant, whether it is responsible for ischemia or symptoms, and whether the coronary anatomy is suitable for catheter-based treatment.
Table of Contents
What does angioplasty and stenting treat?
The procedure is primarily used to treat significant narrowing of the coronary arteries caused by coronary atherosclerosis.
Atherosclerotic plaques can progressively narrow the lumen of an epicardial coronary artery. As the narrowing becomes more severe, coronary blood flow may become inadequate, particularly when the heart’s demand for oxygen increases during exercise or other forms of stress. Plaque rupture can also trigger platelet activation and thrombus formation, potentially producing an acute coronary syndrome.
PCI can be used in different clinical settings, including selected patients with symptomatic coronary artery disease and patients with acute coronary syndromes. In the setting of an acute myocardial infarction, rapid restoration of blood flow to the affected coronary artery is particularly important. Harrison’s describes PCI with stenting as a major method of reperfusion in appropriate patients with acute coronary syndromes.
However, not every coronary narrowing needs a stent.
The decision depends on the patient’s symptoms, evidence of myocardial ischemia, coronary anatomy, overall cardiac function, other medical conditions and whether PCI is technically appropriate.
What is coronary angioplasty?
Coronary angioplasty is a catheter-based technique used to enlarge a narrowed section of a coronary artery.
During PCI, the cardiologist first obtains arterial access, traditionally through either the radial artery at the wrist or the femoral artery. A guiding catheter is then advanced toward the coronary arteries.
A flexible guidewire is passed through the coronary artery and across the narrowed area. The guidewire acts as a rail over which balloons, stents and other devices can be advanced.
A balloon catheter is positioned across the stenosis and inflated.
The balloon temporarily compresses and stretches the diseased segment, increasing the internal diameter of the artery. Balloon treatment can also produce small dissections within the arterial wall. These were an important limitation of early angioplasty because a severe dissection could obstruct blood flow or contribute to acute vessel closure.
This is one of the main reasons coronary stents became such an important part of PCI.
Why is a stent placed?
A coronary stent is a small expandable mesh scaffold that remains inside the artery after the balloon and catheter are removed.
The stent is initially mounted on a deflated balloon. Once positioned across the stenosis, the balloon is inflated, expanding the stent against the arterial wall. The balloon is then deflated and removed, while the stent remains in place.
The stent helps maintain the enlarged arterial lumen and prevents elastic recoil. It can also press small dissection flaps against the arterial wall, reducing the risk of acute closure after angioplasty.
Modern coronary stents are predominantly drug-eluting stents, which release an antiproliferative medication locally. Their purpose is to reduce excessive tissue growth inside the stent and therefore reduce restenosis. Harrison’s describes the major reduction in restenosis achieved with drug-eluting stents compared with earlier bare-metal technology.
The exact type of stent selected depends on the coronary anatomy and clinical circumstances.
What happens during PCI?
Although the details vary between patients, coronary angioplasty and stenting generally follow a sequence like this:
1. Arterial access
A small sheath is inserted into an artery, commonly the radial artery at the wrist or the femoral artery in the groin.
2. Coronary angiography
Contrast is injected through a catheter so the coronary arteries and areas of narrowing can be visualised under fluoroscopy.
3. Guidewire placement
A flexible guidewire is carefully passed through the coronary artery and across the target lesion.
4. Balloon angioplasty
A balloon catheter is advanced over the guidewire and inflated at the site of narrowing.
5. Stent deployment
A stent is positioned across the treated segment and expanded against the arterial wall.
6. Assessment of the result
The cardiologist assesses whether blood flow has been restored and whether the stent is adequately expanded and positioned.
In some cases, additional catheter-based imaging such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT) can be used to examine the artery and assess stent placement. Harrison’s also describes fractional flow reserve as a method of assessing whether an intermediate coronary stenosis is functionally significant.
The procedure is generally performed under local anaesthesia with sedation rather than general anaesthesia. Harrison’s describes PCI as usually requiring only a short hospital stay, although the actual length of admission depends on the patient’s condition, the indication for PCI and whether complications occur.
When might angioplasty and stenting be considered?
PCI is not simply a treatment for an abnormal-looking coronary angiogram.
In chronic coronary disease, revascularisation may be considered when symptoms remain troublesome despite appropriate medical treatment or when the coronary anatomy represents a sufficiently high-risk pattern in which revascularisation may provide prognostic benefit.
In acute coronary syndromes, the situation is different. PCI may be required urgently because restoring blood flow can limit myocardial injury.
The decision therefore depends heavily on the clinical setting.
Symptoms matter
Persistent angina or angina-equivalent symptoms despite appropriate medical therapy can be an important reason to consider revascularisation.
The coronary anatomy matters
The number of diseased vessels, location of the lesions, vessel size, degree of calcification, tortuosity and other anatomical characteristics affect whether PCI is technically appropriate.
Heart function matters
Left ventricular function is an important part of deciding how coronary disease should be treated.
The overall pattern of coronary disease matters
A patient with a relatively discrete lesion may be treated very differently from someone with extensive multivessel or left-main coronary disease.
This is where the distinction between PCI and CABG becomes important.
Angioplasty and stenting vs CABG
PCI and coronary artery bypass grafting both restore blood flow to areas of heart muscle supplied by diseased coronary arteries, but they do so differently.
PCI treats the coronary artery from inside the vessel.
CABG creates a new route around the obstructed coronary segment.
Harrison’s describes PCI as focusing on the culprit lesion, whereas a bypass graft provides a conduit around the diseased segment of the coronary artery.
PCI may therefore be particularly attractive when the coronary anatomy is suitable for catheter-based treatment and a less invasive approach is appropriate.
CABG may be considered when disease is more extensive or anatomically unsuitable for PCI. Diabetes, left ventricular function, left-main or multivessel disease, lesion complexity and other patient-specific factors can influence the decision.
The choice is therefore not simply:
stent versus surgery.
It is a decision about which form of revascularisation best fits the patient’s coronary anatomy and clinical circumstances.
Bailey & Love similarly describes the decision for coronary revascularisation as involving both the appropriateness of revascularisation itself and the relative merits of CABG versus PCI.
What medications are used around a stent?
Because a coronary stent is a foreign surface within the artery, preventing platelet-rich clot formation around the device is an important part of PCI care.
Antiplatelet medications are therefore used around coronary stenting. Harrison’s describes aspirin together with a P2Y12 inhibitor as part of antiplatelet treatment associated with PCI and stent implantation.
The exact medication combination and duration depend on factors such as:
- why the PCI was performed
- the type of coronary intervention
- bleeding risk
- risk of coronary thrombosis
- other medications and medical conditions
- whether the patient has an acute coronary syndrome
One of the most important practical points for patients is that antiplatelet medication should not be stopped independently after coronary stenting.
If another doctor recommends stopping one of these medicines—for example, before surgery or an invasive procedure—the decision should be coordinated with the cardiology team. Harrison’s specifically emphasises coordinated planning when temporary interruption of antiplatelet therapy is necessary because premature interruption can increase the risk of stent thrombosis.
What are the possible complications?
PCI is less invasive than open coronary bypass surgery, but it is still an invasive cardiovascular procedure.
Potential complications include:
- bleeding or complications at the arterial access site
- coronary artery dissection
- acute vessel closure
- myocardial infarction
- coronary thrombosis
- arrhythmias
- contrast-associated kidney injury
- stroke
- stent thrombosis
- restenosis
- rarely, emergency surgery or death
The risk varies considerably according to the clinical situation.
Elective PCI in a stable patient is different from emergency PCI during a large myocardial infarction or cardiogenic shock. Harrison’s notes that advanced age, chronic kidney disease, STEMI and shock are associated with higher procedural risk.
Bailey & Love notes that the development of intracoronary stents has substantially reduced the need for emergency CABG following complications of PCI.
What is stent thrombosis?
Stent thrombosis occurs when a blood clot forms within a coronary stent.
It is uncommon but potentially serious because sudden occlusion of the stented artery can cause myocardial infarction and, in severe cases, death.
Risk is influenced by factors including lesion complexity, stent characteristics, procedural factors and patient factors. Inadequate adherence to prescribed antiplatelet therapy is an important concern.
Symptoms suggesting acute coronary occlusion—such as new severe chest pressure, shortness of breath, sweating, collapse or other symptoms of a heart attack—require emergency medical assessment.
What is restenosis?
Restenosis means that the treated coronary segment becomes narrowed again.
The process historically occurred frequently after balloon angioplasty and bare-metal stenting. Drug-eluting stents substantially reduced this problem by limiting excessive tissue proliferation within the treated segment.
Restenosis can present with recurrence of angina or other evidence of myocardial ischemia. Harrison’s describes diabetes, myocardial infarction, long lesions, small coronary vessels and an initially suboptimal PCI result among factors associated with increased restenosis risk.
When clinically significant restenosis occurs, repeat PCI or another form of revascularisation may sometimes be required.
Importantly, recurrent symptoms after PCI do not automatically mean that the stent has failed. New disease elsewhere in the coronary circulation can also produce symptoms.
What is recovery like after angioplasty and stenting?
Recovery is generally shorter than after CABG because PCI does not require a chest incision or surgical bypass.
After the procedure, the access site is monitored for bleeding or other vascular complications. Patients may be encouraged to maintain appropriate fluid intake and avoid strenuous activity for a period determined by their treating team.
The length of hospitalisation depends on why the PCI was performed.
Someone undergoing planned PCI for stable coronary disease may have a relatively short admission, while a patient undergoing emergency PCI for myocardial infarction may require a substantially longer hospital stay because the underlying heart attack also needs treatment and monitoring.
Recovery from the procedure itself is only one part of treatment.
Long-term coronary care may include:
- antiplatelet therapy
- cholesterol management
- blood-pressure control
- diabetes management when applicable
- smoking cessation
- physical activity and cardiac rehabilitation when appropriate
- dietary and weight management
- treatment of other cardiovascular risk factors
A stent treats the specific coronary lesion. It does not remove the underlying tendency to develop atherosclerotic disease elsewhere in the coronary circulation.
Does having a stent mean the heart disease is cured?
No.
A stent can successfully reopen a narrowed coronary artery, but coronary artery disease is a chronic disease.
A patient can develop:
- disease in another coronary artery
- progression of atherosclerosis
- restenosis within a treated segment
- disease in a bypass graft if they have previously undergone CABG
- recurrent ischemic symptoms for reasons unrelated to the original stent
Successful PCI can provide substantial relief of angina, but long-term management of the underlying cardiovascular risk factors remains important.
Questions to ask the cardiologist before PCI
Before undergoing planned angioplasty and stenting, patients may want to understand:
- Which coronary artery is narrowed and how severe is the disease?
- Is the lesion suitable for PCI?
- What is the expected benefit of treating this lesion?
- Would medication alone be reasonable in my situation?
- Would CABG be a reasonable alternative?
- What type of stent is being considered?
- How long will I need antiplatelet treatment?
- What should I do if another doctor asks me to stop an antiplatelet medication?
- What complications are particularly relevant in my case?
- What follow-up and cardiac rehabilitation will I need afterward?
The key point
Angioplasty and stenting provide a way to treat selected coronary artery blockages from inside the artery rather than by creating a surgical bypass.
The procedure typically involves coronary angiography, passage of a guidewire across the narrowed segment, balloon dilation and deployment of a stent. Drug-eluting stents have significantly reduced restenosis compared with earlier stent technology.
But the presence of a coronary narrowing does not automatically mean that PCI is the right treatment.
The appropriate strategy depends on the patient’s symptoms, evidence of ischemia, coronary anatomy, ventricular function, urgency of treatment, associated medical conditions and the relative suitability of PCI and CABG.
For patients with complex or extensive coronary disease, the decision is best made through a multidisciplinary assessment involving the interventional cardiologist, cardiac surgeon and patient.
Written and Reviewed By Dr. Munaf Ahmad Ansari
Medical information note: This article is written for information purpose only. Individual treatment decisions should be based on contemporary clinical guidelines and assessment by an appropriately qualified medical team.