Bilateral internal thoracic artery grafting: time to reconsider our strategy?

Le résumé fourni par la source

We read with great interest the article by Ogawa et al. [1] dealing with the issue of bilateral internal thoracic artery (BITA) grafting and the results of a propensity analysis indicating the superiority of the right internal thoracic artery (RITA) over its left counterpart as a bypass graft to the left anterior descending (LAD) artery. Despite the proven positive effect on the survival of internal thoracic artery (ITA) grafting in coronary artery bypass grafting surgery through the gold standard approach of in situ left ITA (LITA) to LAD grafting [2], the benefits of BITA grafting over single ITA (SITA) grafting have been widely reported as well [3, 4]. The series by Ogawa and co-authors with its key findings and especially the take-home message may ‘rock the boat’. We would like to take the chance to add some comments on the topic. From the technical point of view, the authors advocate for a certain length of the in situ RITA graft to enable more distal anastomoses on the LAD. This is in our eyes not entirely reproducible. An appropriate length of the in situ RITA graft targeting the peripheral LAD has been among cardiac surgeons one of the major concerns throughout the years. Could the authors illustrate more precise insights and pitfalls regarding either harvesting or guidance techniques to the target vessel (including the positioning in relation to the lung, the way of penetration into the pericardial cavity, etc.)? Furthermore, looking at the baseline characteristics, the unmatched and matched cases presented a significantly higher frequency with 12.5% of ‘sequential anastomosis of the LAD graft in the LITA to LAD group’. As sequential anastomoses carry a potential risk of steal syndrome, it appears reasonable to analyse a possible correlation between this factor and graft patency. Notably, 82.7% out of the 877 cases included in the analysis underwent at least one angiography at a mean duration of 2.2 years after surgery. Especially in the matched population, the rate increased by up to 89%, 50% of which were within the first postoperative year. Nevertheless, a loss of 11% to follow-up may influence the evaluation of mid-term graft patency, on the one hand, and on the other hand, the implementation of two different angiography techniques with varying sensitivities and specificities may bias the results as well. According to our experience in performing BITA grafting, preferring predominant the same, as by the authors proposed, cross arrangement of in situ RITA to LAD and in situ LITA to left lateral wall, with favourable long-term results and acceptable complication rates, we overcame or minimized the risk of RITA damage during resternotomy by covering the vessel graft with a PTFE sleeve [4, 5]. Others propose securing the graft under the pericardial fat and thymic remnants before chest closure [6]. Although in situ RITA to LAD grafting in the setting of BITA configuration seems reasonable with excellent mid- and long-term outcomes, results from prospective randomized trials are still awaited to prove the superiority of the graft over its left counterpart, which may justify a reconsideration of the currently widely adopted surgical strategy.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.