CARDIOVASCULAR JOURNAL OF AFRICA • Volume 34, No 4, September/October 2023 246 AFRICA Nevertheless, the presence of lower PI values in the patients who underwent surgery through induced cardiac arrest may suggest that more ideal conditions can be provided for anastomosis with this method. Although no statistically significant differences were identified, lower anastomosis-related technical problems in patients who underwent on-pump surgery without induced cardiac arrest may indicate that surgeons felt safer with this method than with off-pump surgeries. Th study by Kieser et al. showed that graft revisions are not always required in patients with a measured PI value of ≥ 5.22 In these patients, the PI value can be reduced to less than 5 with simple interventions, including corrections of the position of the graft. A PI value of ≥ 5 indicates that a graft has been revised. Of the patients with a PI value of ≥ 5, four showed sufficient improvement in their PI values with position changes, and three showed sufficient improvement with local papaverine administration but no graft revisions. As in the results of the study by Kieser et al., mechanical problems were eliminated, and the flows were improved prior to graft revision in cases of high PI values and in accordance with our data.22 Many factors affect graft flow, such as graft length and diameter, structure of the native vessel, mean arterial pressure, heart rate, competitive flow with the native vessel, and viscosity of the blood. As in the study by Kieser et al., because all conditions could not be standardised, we performed TTFMs after all the patients’ anastomoses were surgically completed and haemodynamic stabilisation had been achieved.22 Although arterial grafts used in coronary bypass surgery can remain in patients for longer periods of time than venous grafts, venous grafts are considered to provide better flow when the myocardium requires high levels of blood.23 In our study, we compared all grafts with the same grafts in the other groups. Therefore, the flow differences between arterial and venous grafts did not affect our results. Conclusion The quality of anastomosis is the most important factor in coronary artery bypass surgery. Assessing anastomosis quality is an increasingly popular method for evaluating flow in grafts with TTFM and for performing additional surgical interventions based on these values. Studies that compare classical on-pump surgery, on-pump surgery without cardiac arrest, and off-pump surgery, which surgeons avoid since it may reduce anastomosis quality, are quite important. Because the results were similar for the three different methods used by the same surgical team, it is probable that all three methods can safely be used in the presence of sufficient surgical experience. References 1. Tan ES, Jessurun G, Deurholt W, van der Vleuten P, van der Heuvel A, Ebels T, et al. Differences between early, intermediate, and late angioplasty after coronary artery bypass grafting, Crit Pathw Cardiol 2008; 7(4): 239–244. 2. Weman SM, Salminen US, Penthhilä A, Männikkö A, Karhunen PJ. Post-mortem cast angiography in the diagnostics of graft comlications in patient with fatal outcome following coronary artery bypass grafting (CABG). Int J Legal Med 1999; 112: 107–114. 3. Di Giammarco G, Pano M, Cirmeni S, Pelini P, Vitolla G, Di Mauro M. Predictive value of intraoperative transit-time flow measurement for short-term graft patency in coronary surgery. J Thorac Cardiovasc Surg 2006; 132(3): 468–474. 4. Tokuda Y, Song MH, Oshima H, Usui A, Ueda Y. Predicting midterm coronary artery bypass graft failure by intraoperative transit time flow measurement. Ann Thorac Surg 2008; 86(2): 532–536. 5. Windecker S, Kolh P, Alfonso F, Collet JP, Cremer J, Davies J. 2014 ESC/EACTS guidelines on myocardial revascularization: the Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS) developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI). Eur Heart J 2014; 35(37): 2541–2619. 6. Evidence-based recommendations on MiraQ for assessing graft flow during coronary artery bypass graft surgery. NICE medical technologies guidance. Published November 2011. Last updated February 2018. Available at https://www.nice.org.uk/Search?q=the+VeriQ+system. Accessed April 29, 2018. 7. Cooley DA. Beating-heart surgery for coronary revascularization: is it the most important development since the introduction of the heartlung machine? Ann Thorac Surg 2000; 70: 1779–1781. 8. Jegaden O, Mikaeloff P. Off-pump coronary artery bypass surgery. The beginning of the end? Eur J Cardiothorac Surg 2001; 19: 237–238. 9. Kjaergard HK. Baseline flow in coronary bypass grafts. J Card Surg 2005; 20: 205–207. 10. Gwozdziewicz M. Cardiomed coronary flow meter for prevention of early occlusion in aortocoronary bypass grafting. Biomed Pap Fac Univ Palacky Olomouc Czech Repub 2004; 148: 59–61. 11. Di Giammarco G, Pano M, Cirmeni S, Pelini P, Vitolla G, Di Mauro M. Predictive value of intraoperative transit-time flow measurement for short-term graft patency in coronary surgery. J Thorac Cardiovasc Surg 2006; 132: 468–474. 12. Hirotani T, Kameda T, Shirota S, Nakao Y. An evaluation of the intraoprative transit time measurements of coronary bypass flow. Eur J Cardiothorac Surg 2001; 20: 1075–1077. 13. Jokinen JJ, Werkkala K, Vainikka T, Peraklya T, Simpanen J, Ihlberg L. Clinical value of intraoperative transit-time flow measurement for coronary artery bypass grafting: a prospective angiography-controlled study. Eur J Cardiothorac Surg 2011; 39: 918–923. 14. Kaya U, Çolak A, Becit N, Ceviz M, Koçak H. Intraoperative transittime flow measurement in on-pump coronary artery bypass graft surgery: Single center experience. Turkish J Cardiovasc Surg 2018; 2: 167–176. 15. Becit N, Erkut B, Ceviz M, Unlu Y, Colak A, Kocak H. The impact of intraoperative transit time flow measurement on the results of on-pump coronary surgery. Eur J Cardiothorac Surg 2007; 32: 313–318. 16. Canver CC, Cooler SD, Murray EL, Nichols RD, Heisey DM. Clinical importance of measuring coronary graft flows in the revascularized heart. Ultrasonic or electromagnetic? J Cardiovasc Surg 1998; 38: 211–215. 17. Lougaie YA, Haxhe JP, Jamart J, Buche M, Schoevaerdts JC. Doppler flow measurement in coronary artery bypass grafts and early postoperative clinical outcome. Thorac Cardiovasc Surg 1994; 42: 175–181. 18. Jaber SF, Koenig SC, BhaskerRao B, VanHimbergen DJ, Cerrito PB, Ewert DJ. Role of graft flow measurement technique in anastomotic quality assesment in minimally invasive CABG. Ann Thorac Surg 1998; 66: 1087–1092. 19. Schmitz C, Ashraf O, Schiller W, Preusse CJ, Esmalizadeh B, Likungu JA. Transit time flow measurement in on-pump and off-pump coronary artery surgery. J Thorac Cardiovasc Surg 2003; 126: 645–650.
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