Cardiac Rehab Can Be Safely Started 2 Weeks After Surgery: SCAR

Getting patients physically active as early as 2 weeks after a sternotomy for CABG or valve surgery appears to be just as safe and effective as waiting the standard month and a half, according to results of a new randomized trial.

A structured, supervised exercise program started 2 weeks after the procedure should be the norm in the majority of patients, say researchers, who are optimistic their findings will swiftly be absorbed into practice.  

“We’re involved in a lot of the UK’s professional government bodies that write the guidelines and we know that this will be adopted,” senior investigator Gordon McGregor, PhD (University of Warwick/University Hospital Coventry and Warwickshire National Health Service Trust, England), told TCTMD. “There are many clinicians around the UK that have already contacted us and have said they started to do this on the back of these findings. It will certainly be adopted into guidelines in the UK and we hope that it will be adopted elsewhere as well.”

Exactly when cardiac rehabilitation is started after surgery requiring a median sternotomy differs around the world, but it generally doesn’t happen until about 6 weeks after the procedure. However, as McGregor pointed out, starting then is not based on any empiric data and this delay is a missed opportunity for structured rehabilitation and a potentially faster recovery, he said. In fact, researchers point out that many patients even deteriorate while they’re waiting around to start rehab.

They were in a much bigger hole than they needed to be before they started rehab. Stuart Ennis

“Six weeks is quite a long time,” lead investigator Stuart Ennis, PhD (University of Warwick/University Hospital Coventry and Warwickshire National Health Service Trust), told TCTMD. “The reason we decided to do this is that we were seeing patients who had followed the advice literally—they hadn’t even left the house for 6 or 7 weeks—and we were seeing a lot of atrophy. They were in a much bigger hole than they needed to be before they started rehab. It was making everybody’s job harder.”

After a median sternotomy, said Ennis, patients are advised to lift no more than a few pounds, such as a kettle, so that the wound has time to heal. Yet the intrathoracic pressures generated from coughing or sneezing are higher than from many of the daily activities that surgical patients are told to avoid, leading some to believe that the postsurgical recommendations are overly restrictive.     

Careful About Imposing Loads on the Chest

The Early Initiation of Poststernotomy Cardiac Rehabilitation Exercise Training Study (SCAR), published June 22, 2022, in JAMA Cardiology, was a randomized trial testing two different rehab protocols in 158 patients who underwent cardiac surgery. For the usual-care group, participants (mean age 64.0 years; 11.3% female) completed 8 weeks of twice-weekly, 1-hour cardiac rehabilitation started 6 weeks after surgery. In the early-intervention group (mean age 61.6 years; 20.5% female), cardiac rehabilitation started at 2 weeks, with the exercises modified in the first 2 to 3 weeks based on participants’ fitness, symptoms, and limitations.

After 8 weeks of cardiac rehabilitation, which was approximately 10 and 14 weeks after surgery in the two study arms, the mean 6-minute walk test (6MWT) distance for early and usual-care rehab was similar in the two groups. The difference in the mean change from baseline was 27.5 m, which favored early rehab (P = 0.16) and met the study’s primary noninferiority endpoint (noninferiority margin, 35 m). The early-intervention group had a lower baseline 6MWT and had a greater increase in distance over the 8 weeks. The functional improvement with early rehab was achieved 4 weeks earlier in the patients’ recovery time lines.  

The key thing here is the cardiac surgeon, the physician. They need to get on board and speak with patients right at the initial consultation. Gordon McGregor

For other secondary endpoints, such as leg strength, anxiety and depression scores, and health-related quality of life, the early rehabilitation program was noninferior to one started 6 weeks out from surgery.

“We didn’t need to show that starting earlier was superior,” said McGregor. “We just needed to show that it was no worse. Our data clearly supported that.”

To TCTMD, Ennis said it was “eye-opening” to be working with patients so soon after cardiac surgery, and it became evident quite early that many were physically capable of participating in the program. “As long as we’re careful about the loads we’re imposing on the chest, there’s no reason why patients couldn’t perform cardiovascular exercise,” he said. “That was well demonstrated with our 6-minute walk test.”

Overall, there were 18 serious adverse events with the early intervention and 14 with usual care. There was more “sternal instability” with the early intervention (four events versus one with usual care), but this was a quirk of when patients were randomized after surgery. In all cases, the instability occurred and resolved before the patient started the exercise program. Adverse events, in general, were higher when starting rehab at 2 weeks, but McGregor said this is likely because patients had closer and earlier contact with health professionals.

Primary Concern Was Safety

McGregor stressed that their main concern in SCAR was safety, but to definitively prove the earlier intervention was as safe as starting at 6 weeks would require a much larger trial. Nonetheless, based on their data, the researchers believe early rehab doesn’t pose any risks to patients. “We generally believe from our data, having scrutinized it, that [early cardiac rehabilitation] is likely to be safe,” said McGregor.   

Nearly 500 patients were screened and met the inclusion criteria, but 200 declined to participate in the study. The researchers believe this might be because there is some fear around exercising so soon after surgery. To help get patients moving earlier after a sternotomy, it’ll be important to manage patient expectations.

“The key thing here is the cardiac surgeon, the physician,” said McGregor. “They need to get on board and speak with patients right at the initial consultation. They need to say, ‘Alright, I’m going to list you for some serious surgery, it’s going to change your life, but in order to get the most from it, we want to see you in our rehab program within 2 weeks.’ Those patients in the future won’t know any different.”  

Ennis said that moving forward, there will be a need for education programs to help inform healthcare professionals about the safety of starting cardiac rehabilitation so soon after surgery. Like McGregor, Ennis said the key will be the preoperative consultation so that patients are prepared to start moving and lifting just a couple of weeks after sternotomy.

“There will be some patients who have complications—there will be a proportion of patients who can’t start at 2 weeks—but where we can, we get them started within 2 or 3 weeks after surgery,” said Ennis.