What Is Multivessel Disease and How Is It Treated?

Multivessel disease means fatty buildup has narrowed two or more of the main arteries that feed the heart muscle. It is a more widespread form of ordinary coronary artery disease, not a separate illness. For many people with multivessel disease, stents and bypass surgery lead to similar long-term survival, so the choice often turns on repeat procedures, recovery, and specific risk factors such as diabetes or a weak heart.

What Multivessel Disease Looks Like Inside Your Heart

The heart has three main arteries: one running down the front, one wrapping around the left side, and one on the right. Doctors call it multivessel disease when two or more of these, each wider than about 2 mm, have significant narrowing.¹ Having all three narrowed is often called three-vessel disease.

The standard test is a coronary angiogram, in which dye is injected through a thin tube while X-rays film the arteries.² The picture is flat and two-dimensional, so even experienced doctors can struggle to judge narrowings of about 50 to 70%.³ That is why they often add a pressure-wire test, called FFR, which measures whether a narrowing actually starves the heart of blood.⁴ Blockages that look worrying but don’t restrict flow can be left alone, and fewer stents may be needed.⁵

On your cath report, “70% stenosis” means the artery’s opening is narrowed by about seven-tenths of its width. You may see the arteries named LAD, circumflex, and RCA, which are the front, side, and right arteries. It is fair to ask which arteries are involved and whether any pressure measurements were taken.

Symptoms can’t tell you how many arteries are affected. Chest pressure, breathlessness, or tiredness with exertion can happen with one blocked artery or with three. Some people, especially those with diabetes, feel little despite extensive disease.

A CT scan with contrast dye can also picture the heart arteries without threading a tube through a blood vessel. Computer analysis of the images can estimate blood-flow pressure much as a wire test does. A traditional angiogram is still usually needed if stents are placed.

The Three Main Treatment Options

Medicines are part of every treatment plan: cholesterol, blood pressure, and blood-thinning drugs. Cholesterol-lowering statins have been shown to slow the growth of artery plaque and reduce new heart events in men with significant coronary disease.⁶ Adding a stronger cholesterol drug, evolocumab, to a statin after stenting for a heart attack was linked to fewer later events in one study.⁷ For many people with one or two narrowed arteries, procedures add little survival benefit over medicines alone.⁸

Stenting means a doctor threads a catheter from the wrist or groin, inflates a balloon at the narrowing, and leaves a mesh tube called a stent. Modern stents are coated with a drug that slows scar regrowth inside the artery.⁹ Using at least one drug-coated stent lowered the need to reopen the same artery by about a third compared with bare-metal stents.¹⁰

Bypass surgery, formally coronary artery bypass grafting (CABG), is open-heart surgery that uses a blood vessel from the chest, arm, or leg to route blood past the blockages. It has been performed since 1962 and is the long-standing benchmark against which stents are compared.¹¹ Using more than one artery, rather than leg veins, as grafts was linked to lower 10-year death rates, 15.1% vs 17.3%.¹²

The experiences differ a lot. A stent procedure is usually done awake with sedation, and many people go home within a day or two. Several arteries can sometimes be stented in one sitting or across staged procedures. Bypass needs general anesthesia, a chest incision, and usually several days in the hospital. Full recovery typically takes six to twelve weeks, compared with about a week after stenting.

Neither procedure cures the disease. Both treat specific narrowings but don’t stop plaque from forming elsewhere, which is why medicines and lifestyle changes continue for life. Stopping blood thinners early after a stent can risk a clot inside it, so never stop them without your cardiologist’s advice.

Stents Versus Bypass Surgery Over the Long Run

Across ten trials and nearly 8,000 patients followed about six years, 15% of bypass patients and 16% of stent patients died, a difference too small to be sure of.¹³ An earlier five-year trial found nearly identical death rates, 7.6% with bypass and 8.0% with stents.¹⁴ Some long-term analyses with modern stents still find a survival edge for bypass, especially when several arterial grafts are used.¹⁵ Because the overall gap in deaths is small and uncertain, the other outcomes are usually what separate the two options for an average patient.

Repeat procedures are the clearest difference. Over five years, about 30% of stent patients needed another procedure to reopen arteries, compared with about 9% after bypass.¹⁶ With modern stents, repeat procedures ran about 7 per 100 people per year, compared with about 3 per 100 after bypass.¹⁷ Heart attacks were also more common after stents, about 1.9 vs 1.1 per 100 people per year.¹⁸ A repeat procedure is usually another catheter visit to place or reopen a stent, not an emergency.

Stroke risk runs the other way. Bypass carries a somewhat higher stroke risk, about 1.0 vs 0.7 per 100 people per year in one large comparison.¹⁹ In another five-year study, 7.3% of bypass patients had a stroke, compared with 3.1% of stent patients.²⁰

To weigh this for yourself, ask your doctors how your age, other illnesses, and the pattern of your blockages shift these averages. It also helps to ask the surgeon what their own team’s stroke and complication rates are.

How Doctors Decide Which Treatment Fits You

For complex multivessel disease, guidelines favor a Heart Team: an interventional cardiologist and a cardiac surgeon reviewing the case together.²¹ Their choice is often guided by the SYNTAX score II, which combines the complexity of the blockages with factors such as age and kidney function to predict four-year survival with each option.²² Some patients are clearly better suited to one option, while others are judged a toss-up where either is reasonable.²³

Newer CT-based flow testing can change plans. When CT-based flow estimates were added to the team’s review, the overall treatment recommendation changed for 7% of patients.²⁴ The choice of which arteries to treat changed for 12%.²⁵ About 14% of patients were moved to a lower-complexity score, which can tip the balance toward stents.²⁶

Useful questions for the heart team: Have both a surgeon and an interventional cardiologist reviewed your images? What is your SYNTAX score, or how complex are your blockages judged to be? Was pressure testing done on borderline narrowings? What would recovery and the risk of repeat procedures look like with each option?

When the team sees a toss-up, your priorities, such as avoiding surgery or avoiding repeat procedures, can decide. Factors like frailty or lung disease can make surgery riskier regardless of the score.

When Bypass Has a Clearer Advantage

In people with diabetes and multivessel disease, serious events over five years occurred in 26.6% after stents vs 18.7% after bypass.²⁷ Bypass patients had fewer heart attacks and fewer deaths.²⁸ Strokes were more frequent after bypass, though, 5.2% vs 2.4%.²⁹ Among people with type 2 diabetes, bypass outperformed stenting most clearly in those with three narrowed arteries.³⁰

Diabetes tends to cause long, diffuse narrowing that is harder to stent well. A bypass graft skips the whole diseased stretch rather than treating one spot.

A weak heart also favors surgery. Ejection fraction, the share of blood the heart pumps with each beat, is listed on echo reports, and a low value means a weakened heart. In people with a weak heart, 55% were alive ten years after bypass vs 37% after stents in one matched comparison.³¹ Bypass added to medicines also lowered deaths over about ten years compared with medicines alone, 58.9% vs 66.1%.³²

That advantage may not apply to everyone. Very frail people may not tolerate surgery well enough to gain from it, and early risks within the first month were similar for both options in weak hearts. Discuss with your team whether your heart muscle is still alive enough to benefit from restored blood flow.

Left main disease is different. For classic multivessel disease, bypass led to fewer heart-related deaths than stents over ten years.³³ But for narrowing of the left main artery, the short trunk feeding the left side of the heart, outcomes were similar with either approach.³⁴

Does Every Blockage Need Fixing

Many, though not all, studies find better survival when all significant blockages are treated rather than only some.³⁵ Experts suggest complete treatment should be the goal whenever possible.³⁶

In a heart attack, the artery causing it is opened first, and other narrowings are often found at the same time. Treating those other narrowings reduces repeat heart attacks and urgent procedures.³⁷ The benefit came mainly in narrowings of 60% or more; for milder ones, the main outcome didn’t improve.³⁸ These can be treated during the same procedure or at a later, planned visit.³⁹ Ask whether your remaining narrowings will be checked with a pressure test first.

Leaving a blockage alone is not neglect. Mild narrowings that don’t limit blood flow can be safely managed with medicines, and each extra stent carries its own small risks.

Who Gets Multivessel Disease

People 65 and older were nearly twice as likely as those under 45 to need stents in several arteries.⁴⁰ People with obesity were more than two and a half times as likely to have multivessel disease as those of normal weight.⁴¹ Type 2 diabetes roughly doubled the odds, and high blood pressure and abnormal cholesterol also raised them.⁴² Kidney function below 60 on a lab report’s eGFR, a history of heart failure, and family history of heart disease were also linked to multivessel disease in heart-attack patients.⁴³

Many of these risks can be changed, which makes them targets after treatment as well. Blood pressure and blood sugar control protect both your own arteries and your grafts or stents. Quitting smoking is one of the strongest steps after any heart procedure, and weight loss and activity improve several risk factors at once. Family history can’t be changed, but it is a reason to treat other risks sooner.

Recovery, Rehabilitation, and Life Afterward

After stents or bypass for multivessel disease, people who completed cardiac rehabilitation walked farther in a six-minute walk test than those who didn’t.⁴⁴ Their heart pumping strength improved more, too.⁴⁵ Among people in rehab after a heart attack or stent, poorly controlled diabetes and low fitness were the strongest predictors of death.⁴⁶ So ask for a rehab referral, and treat blood sugar control and building stamina as priorities.

Rehab usually means supervised exercise sessions two to three times a week for about 12 weeks. Staff monitor your heart rate and blood pressure while you build activity safely, and you get education on diet, medicines, and stress. Many insurers cover it after stents or bypass, but you often need a referral.

Quality of life over five years was similar after stents and bypass, though it improved faster after stents.⁴⁷ Among people under 65, 56% of stent patients vs 47% of bypass patients were working at five years.⁴⁸ Over five years, bypass cost about 30% more than stenting.⁴⁹

Call your cardiologist if chest pain or breathlessness with exertion returns. Sudden severe chest pain, fainting, or stroke symptoms need emergency care. After bypass, fever, wound redness, or leg swelling at the graft site need prompt review.