Technical features and best practice of using transit-time flow for intraoperative bypass grafts assessment in variable clinical scenarios

Authors: Sigaev I.Yu., Keren M.A., Kazaryan A.V., Starostin M.V., Nazarov A.A., Morchadze B.D.

Company: Bakoulev National Medical Research Center for Cardiovascular Surgery, Moscow, Russian Federation

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Type:  Reviews


For citation: Sigaev I.Yu., Keren M.A., Kazaryan A.V., Starostin M.V., Nazarov A.A., Morchadze B.D. Technical features and best practice of using transit-time flow for intraoperative bypass grafts assessment in variable clinical scenarios. Creative Cardiology. 2023; 17 (1): 25–33 (in Russ.). DOI: 10.24022/1997-3187-2023-17-1-25-33

Received / Accepted:  30.01.2023 / 29.03.2023

Keywords: transit time flowmetry coronary bypass surgery

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Early graft dysfunction during coronary bypass surgery (CABG) is associated with serious clinical consequences, such as acute ischemia or myocardial infarction, which significantly worsens the patient's prognosis. Effective methods of assessing the quality of coronary grafts are important to achieve optimal results of CABG. Preferably, these methods should be available and applied directly during the operation in order to be able to eliminate a technical error. Transit time flowmetry (TTFM) is the most common intraoperative method of graft function assessment. TTFM is technically simple in execution and convenient for making clinical decisions. However, the correct interpretation of the obtained TTFM results is the subject of controversy due to the lack of generally accepted thresholds indicating graft dysfunction. This article presents the practice of optimal use of TTFM in order to identify graft dysfunction, as well as our own experience of using TTFM with a focus on various clinical scenarios accompanied by ambiguous changes in TTFM indicators. Also, the results of the consensus of experts on the problem of intraoperative application of TTFM in performing CABG are presented, which is of great importance for optimizing postoperative outcomes and improving the long-term prognosis.


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About Authors

  • Igor Yu. Sigaev, Dr. Med. Sci., Professor, Head of the Department; ORCID
  • Milena A. Keren, Dr. Med. Sci., Senior Researcher; ORCID
  • Artak V. Kazaryan, Dr. Med. Sci., Senior Researcher; ORCID
  • Maxim V. Starostin, Cand. Med. Sci., Senior Researcher; ORCID
  • Afanasy A. Nazarov, Cand. Med. Sci., Cardiovascular Surgeon; ORCID
  • Beka D. Morchadze, Cand. Med. Sci., Researcher, Cardiovascular Surgeon; ORCID

Chief Editor

Leo A. Bockeria, MD, PhD, DSc, Professor, Academician of Russian Academy of Sciences, President of Bakoulev National Medical Research Center for Cardiovascular Surgery