Comparative Analysis of the Microcirculation During Cardiac Surgery With Minimal Invasive Versus Conventional Extracorporeal Circulation

The aim of the proposed study is to evaluate microcirculatory alterations in patients undergoing open heart surgery with minimal invasive versus conventional extracorporeal circulation.

Study Overview

• Status: Completed
• Conditions: Coronary Artery Disease; Aortic Valve Stenosis; Mitral Disease
• Intervention / Treatment: Device: Sublingual microscopy

Detailed Description

Background: Cardiac surgery is performed with the use of extracorporeal circulation which triggers a systemic inflammatory response leading to end-organ dysfunction. Contemporary minimal invasive extracorporeal circulation represents an evolution of the conventional extracorporeal circulation that reduces systemic inflammatory response and improves clinical outcome in large studies. A potential explanation includes preservation of tissue microcirculation with minimal invasive extracorporeal circulation as the underlying pathophysiologic mechanism.

Aim: The aim of the present study is to detect differences in tissue microcirculation during cardiopulmonary bypass with minimal (study group) versus conventional (control group) in patients undergoing open heart surgery.

Study type: This is a randomized comparative study. Patients: The study group consists of sixty patients scheduled for elective open-heart surgery (coronary artery bypass grafting, aortic valve replacement of combined procedure) at the Cardiothoracic Department School of Medicine Aristotle University of Thessaloniki.

Intervention: Patients included in the study will be randomly assigned in two groups with a computer-generated algorithm. Study group will undergo cardiac surgery with minimal invasive extracorporeal circulation while control group will be operated with the use of conventional extracorporeal circulation.

Protocol: In both groups tissue microcirculation will be assessed with the use of a specifically designed second generation hand-held video monitoring device which uses sidestream dark field (SDF) imaging placed at the sublingual mucosa. Microcirculatory assessments will be performed at the following time-points: before induction of anesthesia (baseline - T0), after induction of general anesthesia (T1), after initiation of cardiopulmonary bypass (T2) and immediately after weaning cardiopulmonary bypass (T3).

Outcomes: The composite primary outcome of the study consists of obtained differences in the main microcirculatory quantitative variables (Proportion of Perfused Vessels, Microvascular Flow Index, Total Vascular Density, Perfused Vessel Density) during defined time points. Secondary outcomes consist of differences in postoperative 30-days morbidity and mortality.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Greece
  • Thessaloniki, Greece, 54636
    • Cardiothoracic Department, AHEPA University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• patients undergoing undergoing open heart surgery with accepted indications under extracorporeal circulation

Exclusion Criteria:

• patients undergoing emergency surgery
• patients in preoperative cardiogenic shock with evidence of tissue malperfusion
• patients with severe peripheral vascular disease
• patients unable to give informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Minimal Invasive Extracorporeal Circulation (MiECC); Patients undergoing cardiac surgery with Minimal Invasive Extracorporeal Circulation.	Device: Sublingual microscopy; Evaluation of microcirculation with sublingual microscopy.
Active Comparator: Conventional cardiopulmonary Bypass (cCPB); Patients undergoing cardiac surgery with conventional cardiopulmonary bypass.	Device: Sublingual microscopy; Evaluation of microcirculation with sublingual microscopy.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of perfused vessels assessed with sublingual microscopy	Proportion of perfused vessels (PPV) assessed with sublingual microscopy.	During surgery, from induction of anesthesia to weaning of extracorporeal circulation
Perfused vessel density assessed with sublingual microscopy	Perfused vessel density (PVD) assessed with sublingual microscopy.	During surgery, from induction of anesthesia to weaning of extracorporeal circulation
Total vascular density assessed with sublingual microscopy	Total vascular density (TVD) assessed with sublingual microscopy.	During surgery, from induction of anesthesia to weaning of extracorporeal circulation
Microvascular Flow Index (MFI)	Microvascular Flow Index (MFI) assessed with sublingual microscopy	During surgery, from induction of anesthesia to weaning of extracorporeal circulation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peak lactate levels	Peak lactate levels during cardiopulmonary bypass in mmol/l	During surgery from induction to weaning of cardiopulmonary bypass
Mean arterial pressure	Mean arterial pressure during cardiopulmonary bypass	During surgery from induction to weaning of cardiopulmonary bypass
Overall mortality rate	Incidence of death from any cause	From surgery to 30 days postoperatively
Rate of preoperative myocardial infarction	Incidence of perioperative myocardial infarction	From surgery to 30 days postoperatively
Rate of postoperative stroke	Incidence of patients that experience a postperative stroke verified with CT brain scan	From surgery to 30 days postoperatively
Rate of postoperative revascularization	Incidence of patients who require postoperative revascularization	From surgery to 30 days postoperatively
Rate of postoperative renal failure	Incidence of patients that experience postoperative acute kidney injury according too AKIN criteria	From surgery to 30 days postoperatively
Rate of re-intubation	Incidence of patients that required re-intubation	From surgery to 30 days postoperatively
Rate of re-operation	Incidence of patients that required a re-operation	From surgery to 30 days postoperatively
Volume of postoperative bleeding	Volume of postoperative bleeding (ml)	From ICU admission to 12 hours postoperatively
Rate of blood product transfusion	Incidence of any blood product transfusion	Postoperatively up to 30 days
Length of ICU stay	Total length of ICU stay in hours	Perioperatively, up to 4 weeks after surgery
Length of hospital stay	Length of hospital stay in days	Perioperatively, from the day of operation up to 4 weeks after surgery

Collaborators and Investigators

• Sponsor: Aristotle University Of Thessaloniki
• Investigators: Study Director: Kyriakos Anastasiadis, Prof., Aristotle University Of Thessaloniki; Principal Investigator: Helena Argiriadou, Assoc. Prof., Aristotle University Of Thessaloniki

Publications and helpful links

General Publications

• Anastasiadis K, Antonitsis P, Deliopoulos A, Argiriadou H. A multidisciplinary perioperative strategy for attaining "more physiologic" cardiac surgery. Perfusion. 2017 Sep;32(6):446-453. doi: 10.1177/0267659117700488. Epub 2017 Mar 10.
• Koning NJ, Vonk AB, Meesters MI, Oomens T, Verkaik M, Jansen EK, Baufreton C, Boer C. Microcirculatory perfusion is preserved during off-pump but not on-pump cardiac surgery. J Cardiothorac Vasc Anesth. 2014 Apr;28(2):336-41. doi: 10.1053/j.jvca.2013.05.026. Epub 2013 Oct 23.
• Kara A, Akin S, Ince C. The response of the microcirculation to cardiac surgery. Curr Opin Anaesthesiol. 2016 Feb;29(1):85-93. doi: 10.1097/ACO.0000000000000280.
• Yuruk K, Bezemer R, Euser M, Milstein DM, de Geus HH, Scholten EW, de Mol BA, Ince C. The effects of conventional extracorporeal circulation versus miniaturized extracorporeal circulation on microcirculation during cardiopulmonary bypass-assisted coronary artery bypass graft surgery. Interact Cardiovasc Thorac Surg. 2012 Sep;15(3):364-70. doi: 10.1093/icvts/ivs271. Epub 2012 Jun 14.
• Donndorf P, Kuhn F, Vollmar B, Rosner J, Liebold A, Gierer P, Steinhoff G, Kaminski A. Comparing microvascular alterations during minimal extracorporeal circulation and conventional cardiopulmonary bypass in coronary artery bypass graft surgery: a prospective, randomized study. J Thorac Cardiovasc Surg. 2012 Sep;144(3):677-83. doi: 10.1016/j.jtcvs.2012.05.037. Epub 2012 Jun 12.

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2021
• Primary Completion (Actual): December 31, 2023
• Study Completion (Actual): December 31, 2023

Study Registration Dates

• First Submitted: July 22, 2022
• First Submitted That Met QC Criteria: July 26, 2022
• First Posted (Actual): July 29, 2022

Study Record Updates

• Last Update Posted (Actual): April 7, 2026
• Last Update Submitted That Met QC Criteria: April 4, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: microcirculation; cardiopulmonary bypass; near-infrared spectroscopy; extracorporeal circulation; cerebral oximetry; Minimal Invasive Extracorporeal Circulation
• Additional Relevant MeSH Terms: Aortic Valve Disease; Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Heart Valve Diseases; Ventricular Outflow Obstruction; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Myocardial Ischemia; Pathological Conditions, Signs and Symptoms; Aortic Valve Stenosis; Disease; Coronary Artery Disease
• Other Study ID Numbers: AUS_CTS

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No