Technique of bilateral internal thoracic artery minimally invasive coronary artery bypass grafting with double-lung ventilation

From the Departments of Cardiac Surgery and Anaesthesiology, Heinrich Heine University, Duesseldorf, Germany. Disclosures: The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest. Received for publication April 19, 2023; revisions receivedMay 16, 2023; accepted for publicationMay 19, 2023. Address for reprints: Alexander Assmann, MD, PhD, Department of Cardiac Surgery, Heinrich Heine University, Moorenstr. 5, 40225 Duesseldorf, Germany (E-mail: alexander.assmann@med.uni-duesseldorf.de). JTCVS Techniques 2023;-:1-5 2666-2507 Copyright 2023 The Author(s). Published by Elsevier Inc. on behalf of The American Association for Thoracic Surgery. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1016/j.xjtc.2023.05.008 Bilateral internal thoracic arteries off-pump MICSCABG with double-lung ventilation. Georg Thieme Verlag KG.


CENTRAL MESSAGE
Anaortic off-pump MICS-CABG allows for minimally invasive revascularization with both internal thoracic arteries by means of double-lung ventilation even in patients with impaired lung function.

Anastomoses
After LITA-RITA T-graft construction, the LITA is typically sutured to the left anterior descending artery and the RITA to coronaries of the (postero) lateral wall (Video 2). For cardiac positioning and target vessel exposure, suctioning positioner devices and stabilizers are utilized. Afterward, a transit-time-flow measurement confirms adequate blood flow to the coronary targets.

RESULTS
So far, 16 patients have undergone BITA-MICS-CABG in our department (baseline characteristics are presented in Table E1). All patients received a LITA-to-left anterior descending artery bypass and an RITA T-graft to either a diagonal (n ¼ 11) or an obtuse marginal branch (n ¼ 5). During the whole operation (cut-suture time 347.3 AE 59.6 minutes), patients showed adequate pulmonary gas exchange and aerobic metabolism ( Figure E1). All patients were extubated on the day of surgery and showed regular postoperative cardiac enzymes and in-hospital outcome (Table E2).

DISCUSSION
BITA-MICS-CABG allows for totally arterial revascularization without aortic manipulation via anterolateral minithoracotomy. Anaortic coronary surgery decreases the risk of intraoperative stroke, 4 and the long-term patency of arterial grafts should be considered superior to venous bypasses. 5 Compared with OPCAB via sternotomy, MICS-CABG results in fewer wound infections, more rapid recovery, and reduced length of hospital stay. 1 Our pulmonary fan technique guarantees continuous double-lung ventilation and adequate gas exchange without impairing the surgeon's view and working space. Thereby, even patients with impaired lung function can benefit from MICS-CABG. Furthermore, inherent issues of single-lung ventilation (ie, hypoxemia, pulmonary hypertension, and acute lung injury) may be avoided. Left lung ventilation is all the more important for BITA-MICS-CABG because right lung extension frequently has to be partially restricted during RITA preparation. Moreover, compared with minimally invasive direct CABG with only 1 anastomosis, multivessel MICS-CABG requires substantially more time so that adverse cascades triggered by single-lung ventilation have greater influence on the patient. Thus, continuous double-lung ventilation has the potential to avoid conversions to cardiopulmonary bypass and sternotomy. Actually, the usefulness of left lung ventilation to make sternal sparing coronary surgery accessible to a larger group of coronary artery disease patients has been previously shown in the context of robotic totally endoscopic bypass grafting. 6 MICS-CABG is a complex microsurgical procedure, particularly when combined with BITA use. To guarantee a safe procedure and optimal long-term graft patency, an expert team is required, including trained cardioanesthetists. The specialization process of a MICS-CABG team should start from profound expertise in OPCAB, including complications management. Further learning steps comprise basic elements of MICS, adoption of minimally invasive direct CABG with a single anastomosis, evolution toward multivessel MICS, and finally integration of BITA preparation.

CONCLUSIONS
BITA-MICS-CABG is an excellent, innovative approach that combines the advantages of off-pump surgery without aortic manipulation, totally arterial revascularization, and minimal invasiveness. Thus, multivessel arterial bypass grafting is realized in conjunction with reduction of surgical trauma and operative risk. The presented double-lung ventila-tion technique counteracts pathomechanisms inherent to MICS under single-lung ventilation and expands the spectrum of eligible patients toward those with concomitant lung diseases.   Values are presented as mean AE SD or n. CPR, Cardiopulmonary resuscitation; CK, creatine kinase; CK-MB, creatine kinase-cardiac isoenzyme; Ths, T high sensitive; LVEF, left ventricular ejection fraction; CVVHDF, chronic veno-venous hemodiafiltration. *postoperative bleeding from severe pleural adhesions prepared during MICS-CABG.