European guidelines for the management of acute coronary syndromes highlight the importance of using multiple arterial grafts due to their superior patency and better long-term clinical outcomes. However, they acknowledge that the need for emergent surgical revascularization may influence graft selection, as harvesting arterial conduits extends operative time. Consequently, coronary artery bypass grafting (CABG) based on total venous grafting or the use of a single left internal mammary artery (LIMA) combined with additional venous grafts is widely accepted in this context. Given the well-documented advantages of multiple arterial grafts, should we settle for the conventional approach?

This study, published in the Brazilian Journal of Cardiovascular Surgery, analyzed the short- and mid-term clinical outcomes of patients with acute myocardial infarction (AMI) undergoing CABG with either a single arterial graft (SAG) or multiple arterial grafts (MAGs). A retrospective cohort analysis was performed using the REPLICCAR II database, a prospective, observational, multicenter registry including data from patients who consecutively underwent CABG at five hospitals in São Paulo, Brazil, between July 2017 and June 2019. A total of 4,053 patients were included, with CABG considered within the AMI context when performed between one and seven days after diagnosis (n = 238).

A total of 36 patients underwent revascularization with multiple arterial grafts. One patient died intraoperatively and was therefore excluded from the mid-term outcome analysis. Propensity score matching (PSM) was used to compare these patients with 35 individuals who underwent revascularization with a single arterial graft. Mid-term follow-up was conducted through a structured telephone survey between October and December 2022.

The groups exhibited no significant differences in baseline characteristics. Although there was a statistically significant difference in operative duration between the groups (MAG: 4.78 hours, SAG: 4.11 hours, p = .040), no significant differences were observed in cardiopulmonary bypass (CPB) time or aortic cross-clamp time. In the MAG group, the most commonly used grafting strategy involved bilateral internal thoracic arteries (62.86%), followed by the radial artery combined with the left internal thoracic artery (28.57%), and a combination of all three grafts (8.57%). No significant differences were noted in in-hospital outcomes, and the use of multiple arterial grafts in AMI was not associated with worse clinical outcomes in mid-term follow-up. The Kaplan-Meier survival curve demonstrated a trend toward improved survival in the MAG group, although this difference was not statistically significant (p = .63).

The authors concluded that the use of multiple arterial grafts in patients with acute myocardial infarction is not associated with worse short- or mid-term clinical outcomes. Although surgery is prolonged, in-hospital outcomes are comparable to those of patients receiving a single arterial graft. The authors suggest that, despite the challenges of emergency settings, multiple arterial grafts remain a viable option for selected patients, provided that careful preoperative assessment is performed.

The study has some limitations, including its retrospective design and the potential influence of uncontrolled variables. Additionally, the relatively small MAG group size may limit the generalizability of the findings.

COMMENTARY:

For a long time, the prevailing belief has been that in emergency situations, where time is critical, the use of venous grafts or a combination of arterial and venous grafts is more practical due to the rapidity of their harvesting and the immediate hemodynamic performance of venous grafts compared to multiple arterial grafts. This perspective has limited the development of studies supporting total arterial revascularization, and the lack of scientific evidence has restricted the recommendation of this strategy.

However, in recent years, studies have emerged suggesting that the use of multiple arterial grafts in acute myocardial infarction is safe in the short and mid-term and could improve long-term survival by not increasing the risk of complications in the AMI setting. This brings a new perspective to urgent surgical revascularization, enabling the provision of a safe, effective, and durable approach for patients.

As with other surgical techniques, continuous training leads to improvement. Therefore, it seems reasonable to think that if we were to adopt this strategy as a standard approach in the acute phase of myocardial infarction, it could eventually become the technique of choice without an unmanageable increase in surgical time. Moreover, it is noteworthy that even with prolonged operative times, as reflected in the study by Lacava et al., this does not have a negative prognostic impact on the patient.

Other studies, such as the one published by Grieshaber et al. in 2018, have already pointed to these outcomes regarding total arterial revascularization in AMI, showing that it does not excessively prolong surgical times and advocating for the feasibility of this strategy.

The success of this approach relies heavily on the appropriate selection of patients, taking into account factors such as hemodynamic stability, the extent and anatomical characteristics of coronary artery disease, pre-existing glycemic control, and other comorbidities. Although in daily practice and critical situations, venous grafting remains the preferred choice, multiple arterial grafts can be a viable option for selected AMI patients, provided that the decision is based on a comprehensive risk-benefit assessment.

REFERENCE:

Lacava L, Borgomoni GB, Lopes L de M, Freitas LP de, Freitas FL, Dallan LRP, et al. Is it safe to use arterial grafts in patients with acute myocardial infarction? Short-mid-term propensity analysis. Braz J Cardiovasc Surg. 2024;e20230384(e20230384). http://dx.doi.org/10.21470/1678-9741-2023-0384

Grieshaber P, Oster L, Schneider T, Johnson V, Orhan C, Roth P, et al. Total arterial revascularization in patients with acute myocardial infarction – feasibility and outcomes. J Cardiothorac Surg. 2018;13(1):2. http://dx.doi.org/10.1186/s13019-017-0691-4

Byrne RA, Rossello X, Coughlan JJ, Barbato E, Berry C, Chieffo A, et al. 2023 ESC Guidelines for the management of acute coronary syndromes. Eur Heart J Acute Cardiovasc Care. 2024;13(1):55–161. http://dx.doi.org/10.1093/ehjacc/zuad107