The Ottawa Heart Institute has led the first randomised trial showing that a less-invasive approach to multivessel coronary artery bypass surgery can accelerate early recovery while preserving safety and effectiveness compared with conventional open surgery.
Faster recovery, similar long-term results
One month after the operation, patients who underwent the minimally invasive procedure reported better physical recovery than those who had traditional surgery. They also required fewer blood transfusions and spent less time on mechanical ventilation, according to results from the MIST Trial, conceived, designed and led at the Ottawa Heart Institute.
At one year, outcomes were similar in both groups: there were no deaths or strokes reported and patients experienced comparable relief from chest pain, the study found.
What the research means for patients and centres
The trial's lead methodologist, George Wells, PhD, emphasised the practical takeaway for patients: in centres with experienced teams, the minimally invasive option can be safe and allow people to return to their daily lives sooner.
“The message for patients is simple: in centres with experienced teams, minimally invasive bypass surgery is a safe option that helps people return to their daily lives sooner.”
The minimally invasive multivessel bypass technique was developed at the Ottawa Heart Institute, and the study reflects the centre's role in cardiovascular innovation. The investigators describe the MIST Trial as an international effort that addresses a long-standing gap: until now, evidence comparing minimally invasive and conventional coronary bypass had been limited, largely observational and often single-centre.
By providing randomised data, the MIST Trial offers stronger evidence to inform surgical decision-making, training programs and the careful rollout of the technique at hospitals that possess the needed expertise.
- Early benefits: improved physical recovery at one month, fewer transfusions, reduced time on ventilation.
- Safety and effectiveness: comparable one-year outcomes with no deaths or strokes, and similar relief from chest pain.
- Implementation caveat: benefits observed when procedures are performed by experienced surgical teams.
Implications for Canadian cardiac care
The trial cements a milestone for Canadian cardiac surgery, demonstrating that a technique developed in Ottawa can stand up to rigorous, randomised comparison. For health systems and surgical centres, the findings point to potential gains in early patient recovery and resource use — such as blood products and ventilator time — but they also underline the importance of concentrated expertise before broader adoption.
The authors call for expanded training and further research to guide implementation. Centres considering the technique will need to ensure surgical teams have appropriate experience and institutional support to replicate the trial's results safely.
| Time point | Minimally invasive bypass | Conventional bypass |
|---|---|---|
| 1 month | Better physical recovery, fewer transfusions, less ventilation | Slower recovery, more transfusions, more ventilation |
| 1 year | No deaths or strokes; comparable chest pain relief | No deaths or strokes; comparable chest pain relief |
For patients and clinicians weighing surgical options for multivessel coronary disease, the MIST Trial provides timely evidence: where surgical teams have the requisite expertise, minimally invasive multivessel bypass appears to be a viable option that can shorten the early recovery period without sacrificing the outcomes patients and surgeons prioritise.
As the technique spreads, health authorities and training institutions in Canada will face decisions about investment in training, proctoring and case selection to ensure the trial's benefits are realised rather than diluted during broader implementation.
