Relatively young adults with heart disease will have to consider both the risk of complications and the long-term outcomes

If you have severe narrowing of the main heart arteries which compromises the blood flow to a large part of the heart muscle, you will often have to make a decision between opting for a coronary (heart) artery bypass graft surgery (CABG) or undergo percutaneous coronary intervention (PCI) – opening of the heart arteries with minimally invasive techniques using balloons and stents (small cylindrical meshes which are used to open heart arteries).  If you are 50 years or below, the decision becomes more critical as you will have to look at both the risk of complications and the long term outcomes.

Complications after heart bypass graft surgery

In a study published in Heart journal in 2003, an analysis of more than 200 000 patients who had undergone CABG showed for every 1000 patients who have undergone CABG, 21  died within the first month, 24 had non-fatal heart attacks, 13 had non-fatal stroke, 15 had  bleeding from stomach or gut and 8 developed kidney failure.

The data showed that about 8% of patients undergoing CABG have serious major fatal and non-fatal complications. This does not include less serious complications such as abnormal heart rhythms, infections and cognitive impairment.

The National Health Service (NHS) in United Kingdom states that up to 1 in 3 people who have a CABG will develop an irregular heart rhythm problem called atrial fibrillation. In most patients, this can be treated with medication but it can become persistent and cause swelling of heart chambers, reduce heart pump function, and predispose to stroke. The NHS advisory states that the infection of the chest or leg wounds occurs in about 1 in 25, and up to one in every 20 people experience memory and cognitive impairment after a CABG and although it usually improves, it can be permanent.

Long term outcomes

There is very limited data on the long term outcomes of CABG in young adults aged 50 years or younger. A recent publication in the Circulation journal on more than 4000 adults, 50 years or younger, who underwent CABG from 1997 to 2013 provided some insights on the outcomes of young adults who undergo CABG.  The study examined real world data from the SWEDEHEART registry which was linked to the national Swedish health register. During the period of follow-up (maximum  16 years, median about 11 years), 1 in 8 died, 1 in 7 had to undergo another procedure to open the heart arteries, and 1 in 3 had a major complication (heart attack, stroke or death). Following 5, 10, and 15 years after CABG, the patient survival was 96%, 90% and 82%, respectively, and the percentage of “well” patients (those who had no major complications, repeat heart surgeries or repeat hospitalisation) was 83%, 68%, and 51% of patients, respectively. Hence, 15 years after CABG, although the patients were only in their fifties or sixties, almost 1 in 5 had died and only half were well without complications or rehospitalisation.

The inevitable degeneration of vein grafts over time will contribute to the increasing incidence of complications for those with CABG. For those who have had CABG, a small percentage will experience closure of vein grafts within the first 2 weeks and by 18 months more than 40% of vein grafts will be occluded. By 15 years, about 85 percent of heart bypass vein grafts become narrowed or occluded. While graft narrowing can be treated by PCI, total graft occlusion cannot be treated with PCI. The degeneration of vein grafts is often accompanied by increased narrowing and often occlusion of the grafted native heart artery.  This may eventually lead to the need for a second CABG. The risk of death within the first month of a repeat second CABG was reported to be 4.8% by Australian surgeons in the Annals of Thoracic Surgery in 2009.

Comparing CABG and PCI

It is not infrequent for the young patients to want to consider PCI as an alternative option to CABG. The CRAGS (The Coronary aRterydiseAse in younGadultS) study, published in the American Journal of Cardiology in 2014, retrospectively studied more than 2200 consecutive patients of 50 years or less who underwent CABG or PCI between 2002 and 2012. The study reported that PCI was associated with a trend toward better 5-year survival than CABG but PCI was associated with higher rates of heart attacks and repeat procedures. In this study, the 5 years survival was similar for diabetics in both PCI and CABG groups.

Often when a patient has multiple heart artery blockages involving more than one major heart artery, the heart specialist may only open one heart artery with stents and hence, it is not surprising that the PCI patients have more risks of recurrent procedures and heart attacks. More recent data from centres with highly experienced PCI operators where the doctors are able to perform complete opening of all the major heart artery blockages with stents show that patients who undergo PCI in these centres do not have an increased rate of repeat procedures or heart attacks during long term follow-up when compared to CABG. For those with a major heart attack, those who underwent PCI had a better 5 year survival than those who underwent CABG.

Making the final decision

Almost all studies which compare CABG to PCI routinely track major complications such as heart attacks, stroke, deaths, and repeat heart surgeries to make a comparison. Other adverse outcomes associated with CABG such as wound infection, memory loss, decrease in concentration, numbness over skin, leg swelling where the vein graft was removed, irregular heart rhythms, decreased lung capacity (due to injury to nerve to diaphragm muscle or chronic accumulation of liquid in the chest), and impaired kidney function are not routinely considered when making the comparison between CABG and PCI. This is an important point to remember when you read reports comparing CABG and PCI.

When comparing the major and minor complications of PCI and CABG in the young, the recent study showed that if early outcomes were considered, the data favoured PCI as CABG was associated with complications not seen with PCI, such as stroke, wound infection, cognitive impairment, procedure related atrial fibrillation and damage to the nerves that control the diaphragm muscle. CABG was also associated with a higher risk of death. In addition, 15 years after CABG,  although these patients were still relatively young, almost 1 in 5 had died, only half remained well without complications or rehospitalisation, and about 85% of the vein grafts would be narrowed or occluded.

Finally, a few points to remember before making the final decision:

1) Whether a patient with blocked heart artery ends up with CABG or PCI is not only dependent on his medical condition and the severity of his heart artery disease, but also the skill and experience of the heart specialist;

2) Complex disease and chronic total occlusions (CTO) of the heart arteries cannot be routinely opened by heart specialists and require highly experienced heart specialists. Hence for those who want to opt for PCI, before making a final decision, it will be useful to understand the current experience of the doctor, the success rate for  complex CTO procedures , safety record and follow-up outcomes;

3) Opening of all the significant blockages in the major heart arteries is an important consideration to prevent future heart attacks and repeat procedures for those undergoing PCI during long term follow up;

4) In hospitals where expertise for complex PCI procedures are not available, and the surgeons are highly skilled in CABG, CABG remains a good option for complex heart artery disease;

5) Last but not least, optimal medical treatment including control of all major risk factors is extremely important for ensuring good long term outcomes after PCI or CABG.