New coronary artery disease dilemma: Surgically treat all diseased arteries, or just the main offender?

This study involved heart attack patients who had more than one heart artery blocked and investigated whether is was safer to surgically treat all of the blocked arteries or only treat the main artery causing the heart attack. 

A heart attack occurs when blood flow to the heart is blocked. This mostly occurs when there is a build up of cholesterol in the walls of arteries that supply the heart muscle (coronary arteries) with blood, oxygen and nutrients it needs to survive.

A heart attack can damage part of the heart muscle and immediate treatment is needed to prevent this. A type of heart attack, called an ST segment elevation myocardial infarction (STEMI), is caused by a prolonged period of blocked blood supply that affects a large area of the heart muscle. A STEMI is so called because in an electrocardiogram (ECG), which is used to measure the heart's electrical activity and function, the ST segment on the graph is elevated and is thus used to diagnose this particular type of heart attack. 

A procedure used to treat heart attack is heart angioplasty and stenting (also called percutaneous coronary intervention (PCI)). This involves the insertion of a small flexible tube (catheter) into an artery, normally in the groin area. The tube is moved along the blood system until it reaches the blocked artery and a small balloon within the tube is then inflated within the artery to dilate it and improve the blood flow. A mesh stent is then placed in the artery to keep it open.

Sometimes more than one coronary (heart) artery is narrowed or blocked. In this case, the patient is said to have multi-vessel coronary artery disease. However, it is not clear whether it is safer to treat all blocked coronary arteries (known as multi-vessel PCI) or to only treat the main artery (culprit artery) causing the heart attack (known as culprit-only PCI). Multi-vessel PCI may help prevent the risk of the other narrowed or blocked arteries causing a heart attack in the future but it also may put stress on the heart during and shortly after the surgical proedure. 

This article carried out a review of 26 past studies to compare the safety of multi-vessel PCI with culprit-only PCI in patients with STEMI. 

The study found that there was no signifiant difference in the number of patients who died in hospital after multivessel PCI and culprit-only PCI. When multivessel PCI was performed as a staged procedure (not performed on the same day as STEMI diagnosis), however, there was 65% reduced odds of hospital mortality compared to an immediate multivessel PCI following diagnosis. Multivessel PCI was associated with a reduction in the risk of mortality in the long-term and reduced the need for repeat PCI surgery, when compared to culprit-only PCI. 

The study concluded that when multivessel PCI was carried out as a staged procedure, it improved short- and long-term survival and reduced the need for repeat PCI surgery. 

Multi-vessel PCI also has disadvantages including an increased risk of surgical complications, such as an increased risk of a blood vessel rupturing during surgery, and temporarily slowing blood flow during balloon inflation when the blood flow to the heart is already compromised. Also this study is a review of different studies so it provides a clear insight into multi-vessel PCI but may not be strong enough to change clinical practice. 

If you or someone you know have a heart attack, or, are at risk of having a heart attack, and have more than one coronary artery blocked, talk to a doctor about the safety and benefits of multi-vessel PCI.