Central and Peripheral Circulation Differ during Off-Pump Coronary Artery Bypass Grafting

Lars Saemann; Alina Zubarevich; Folker Wenzel; Jasmin Soethoff; Sevil Korkmaz-Icöz; Fabio Hoorn; Matthias Karck; Andreas Simm; Gábor Szabó; Gábor Veres

doi:10.31083/j.rcm2501030

Central and Peripheral Circulation Differ during Off-Pump Coronary Artery Bypass Grafting

Rev Cardiovasc Med. 2024 Jan 16;25(1):30. doi: 10.31083/j.rcm2501030. eCollection 2024 Jan.

Authors

Lars Saemann^{1

2}, Alina Zubarevich^{2

3}, Folker Wenzel⁴, Jasmin Soethoff², Sevil Korkmaz-Icöz^{1

2}, Fabio Hoorn^{2

3}, Matthias Karck², Andreas Simm¹, Gábor Szabó^{1

2}, Gábor Veres^{1

2}

Affiliations

¹ Department of Cardiac Surgery, University of Halle, 06120 Halle, Germany.
² Department of Cardiac Surgery, University of Heidelberg, 69120 Heidelberg, Germany.
³ Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, 30625 Hannover, Germany.
⁴ Faculty Medical and Life Sciences, Furtwangen University, 78054 Villingen-Schwenningen, Germany.

Abstract

Background: Off-pump coronary artery bypass grafting (OPCAB) is an alternative to on-pump coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). During OPCAB, the temporary use of an intracoronary shunt and inotropic medication or catecholamines should keep the central hemodynamics constant. Nevertheless, the need for conversion to on-pump CABG often occurs unexpectedly, most likely due to circulation instability. Circulation instability can appear first in peripheral body parts; therefore, peripheral microcirculation might serve as a predictor for the upcoming conversion to on-pump CABG. We investigated the impact of coronary artery ligation and shunt insertion during OPCAB on cutaneous microcirculation (cLDP) with Laser Doppler Perfusion Technology and transcutaneous oxygen partial pressure ( ${tcpO}_{2}$ ).

Methods: In a pig model of OPCAB, peripheral circulation was evaluated after cLDP (N = 17) and ${tcpO}_{2}$ (N = 6) monitoring. Systolic, diastolic, and mean arterial pressure were also observed to prove the independence of perfusion measurement results from hemodynamic parameters.

Results: Ligation time during cLDP and ${tcpO}_{2}$ monitoring were 101 $\pm$ 49 s and 83 $\pm$ 33 s, respectively. Shunt time was 11 $\pm$ 3 min during cLDP and 13 $\pm$ 2 min during ${tcpO}_{2}$ measurement. Ligation of the left anterior descending coronary artery (LAD) reduced cLDP significantly to 88 $\pm$ 14% (p = 0.007) and ${tcpO}_{2}$ to 71 $\pm$ 25% (p = 0.038). Inserting a temporary shunt into the LAD significantly improved cLDP (p = 0.006) and ${tcpO}_{2}$ (p = 0.015) compared to ligation. cLDP was restored to 99%, and ${tcpO}_{2}$ was restored to 91% of the baseline level before ligation. All hemodynamic parameters remained stable and did not change significantly during OPCAB.

Conclusions: Although hemodynamic parameters stayed constant, peripheral microcirculation was influenced markedly during OPCAB. Inserting a temporary shut into the LAD leads to a complete normalization of peripheral microcirculation, regarding evaluation by cLDP and ${tcpO}_{2}$ .

Keywords: CABG; OPCAB; cutaneous oxygen partial pressure; microcirculation; perfusion.