A game-changer for people diagnosed with stable coronary heart disease

My friend, your columnist and the much lamented fount of medical wisdom, the late Maurice Neligan, must be having a wry smile at heaven's 19th hole as he reflects on the recently published results of a major trial that looked at the relative merits of coronary artery bypass graft (CABG) surgery and stenting (percutaneous coronary intervention – PCI) in patients with stable coronary heart disease.

Having pioneered heart bypass surgery in Ireland and, along with his fellow cardiac surgeons, given a new lease of life to many people, Maurice witnessed the rise of the non-surgical practice of balloon angioplasty and stenting as an effective means of treating blocked coronary arteries.

It must be said that he had nothing but praise for the new technique; but I wonder if he ever thought surgical treatment had been ever so slightly marginalised?

Until the publication last month of the Syntax trial in the medical journal The Lancet, the general consensus was that inserting a stent via an incision in the groin offered the same survival benefits as open heart bypass surgery.

The Syntax results suggest otherwise: it found that CABG results in half the death rate and one- third the heart attack rate of PCI some five years after either procedure has been carried out.

Randomly assigned
Syntax followed up 1,800 patients with severe coronary artery disease: one group of patients was randomly assigned to surgical treatment in the form of CABG; the second group was treated with stenting (PCI).

After five years, surgery was found to have limited major adverse cardiac and cerebrovascular events to 27 per cent of participants in the CABG group compared with a complication rate of 37.3 per cent in the PCI group.

While almost 10 per cent of those who underwent a stenting procedure had had a heart attack at follow-up, just under 4 per cent of those who had a CABG suffered a heart attack.

Deaths from a cardiac cause were at 5 per cent of those who went down the bypass route, compared with 9 per cent of participants who had a stent inserted.

And when it came to the need for a repeat procedure over the five years, some 14 per cent of the CABG group required one as against 26 per cent of those who underwent a PCI.

Heart team
Away from the figures, the researchers found those who had been looked after using a team approach did better. In other words, rather than cardiac surgeons and cardiologists working in isolation, being treated by a "heart team" – consisting of a core minimum of an interventional cardiologist and cardiac surgeon, and recruiting additional expertise as necessary – produced the best outcomes.

Number of variables
Which seems logical when you consider the number of variables that may apply to each individual patient.

Older patients, in general, pose a greater surgical risk while those with diabetes tend to have different patterns of heart disease compared with the rest of the population.

In a related paper, the authors describe a new scoring system, an attempt to quantify the risks and probable outcome of CABG or PCI in individual patients by combining the purely anatomical Syntax score with clinical factors.

Although yet to be proven to be effective, this approach to decision-making makes intuitive sense.

What is not in doubt is that having a stent inserted is the treatment of choice for someone who develops chest pain out of the blue and is found to have an acute coronary blockage.

But this latest research is a game-changer for people diagnosed with stable coronary artery disease.

Depending on the exact location and number of blockages in the coronary system, bypass surgery may well be a better long-term option.

The most important point to emerge from this research for anyone faced with coronary artery disease is to ask for their case to be discussed at a multidisciplinary meeting at which both a cardiac surgeon and cardiologist are present.

mhouston@irishtimes.com
muirishouston.com