Minimally invasive cardiac surgery more beneficial than median sternotomy in Asians

A minimally invasive cardiac surgery (MICS) is both safe and effective in a carefully selected group of cardiac patients in Singapore, producing better outcomes when compared with conventional median sternotomy (MS), according to a study.

“[O]ur study demonstrates that it is possible to establish a Singapore-based MICS program comparable with other leading MICS programs that is able to confer a high standard of care without compromising safety,” said the researchers, led by Zhi Xian Ong from the Department of Cardiac, Thoracic and Vascular Surgery, National University Heart Centre Singapore.

Ong and colleagues included patients who had undergone cardiac procedures, such as heart valve replacement or repair, coronary artery bypass grafting, or atrial septal defect repair. They analysed a total of 4,063 and 390 patients who were treated with MS and MICS, respectively, between January 2009 and February 2020.

The number of MICS procedures performed increased over the years. MICS operations with two or more concomitant cardiac procedures also increased, while postoperative length of stay decreased. [Singapore Med J 2022;63:641-648]

Patients who underwent MICS had shorter length of postoperative hospital stay than those who underwent MS (p<0.001). In addition, multivariate analysis revealed that MICS was associated with lower rates of atrial fibrillation (p=0.021), reoperation (p=0.028), and prolonged ventilation (p<0.001).

On the other hand, the rates of other postoperative complications were similar between patients in the MICS and MS groups.

“The results of this study provide further evidence and support towards adopting the minimally invasive approach to cardiac surgery in a carefully selected group of cardiac patients in Singapore,” the researchers said.

The finding on shorter hospital stay among MICS patients is supported by previous studies, but the overall postoperative length of stay of patients who underwent MICS in the Singapore institution was slightly longer than that reported in other MICS series. [Ann Surg 1997;225:805-811; Eur J Cardiothorac Surg 2012;42:648-652]

“The longer duration in our cohort is likely attributable to a variety of medical and social factors,” the researchers said. “Medical factors include that of anticoagulation to achieve therapeutic levels and strict institutional discharge protocols centring on rehabilitation progress, which pose a challenge to discharging patients earlier into the community.”

In terms of social factors, the availability of caregivers and step-down care facilities usually lead to additional postoperative length of stay.

“Hence, while we offer a less invasive patient experience, we are often faced with artificial delays, which offset the anticipated impact of our MICS program on the length of stay,” the researchers said. “Nevertheless, increased experience with MICS and focus towards a fast-track recovery program likely contributed to the improved length of stay in the patients after 2017.”

The MICS program in Singapore is supported by educational, research, and innovation outputs, along with strong organizational support and industry liaisons.

“This study provides convincing evidence that MICS is beneficial for our patients, while retaining surgical safety and efficacy. With continued growth in this program, MICS can become a new gold standard for selected patients scheduled to undergo cardiac surgery and selected conditions, if provided appropriate in-situ and in-silico training,” the researchers said.

“More data in matched populations is required to provide further evidence regarding the benefits of MICS in our mixed-ethnic population,” they noted.