Kevin McCusker Ph.D., MSc, CCP, Chief Research Scientist

Professor Serdar Gunaydin M.D, Ph.D.

Traditionally, scientists have bridged the gap between the clinic and the laboratory. Scientist-Perfusionists now hold professional degrees related to clinical care (i.e., Ph.D., CCP, RN, RRT, and MT) but spend most of their time in the clinical arena. Through our unique combination of clinical and research experience, we look for insight into the molecular discordance that underlies disease etiology. Scientists-Perfusionist convert scientific findings into clinically relevant applications and elucidate the mechanisms that cause clinical problems. A relative decline in the scientist-perfusionist population threatens cross-talk between the laboratory and clinic. Researchers are less aware of potential clinical implications for molecular discoveries and are not privy to the clinical observations and needs that fuel clinically relevant research. The flow of information between the lab and clinic slows. Professor Gunaydin and I worry that perfusionist-scientists will become scarcer in the future, restricting this information stream to a trickle. With fewer perfusionist-scientists to intercede, cultural and professional differences between perfusionists and researchers may compromise the flow of information between these worlds, widening the current rift. With these thoughts in mind, we would like to present another of our recent studies; please feel free to comment directly to us with any additional ideas or thoughts towards furthering our studies.

Protective Efficacy of Minimally Invasive Techniques on Endothelial Glycocalyx In Aortic Valve Surgery”

The endothelial glycocalyx (EG) is fundamentally involved in numerous physiologic and pathophysiologic actions in the circulatory system. The present study aimed to compare plasma levels of syndecan-1, a biomarker of EG integrity, in patients undergoing minimally invasive aortic valve surgery compared to conventional techniques verified by cell culture.

Methods: This prospective cohort study included high-risk patients (Euroscore II >5) undergoing aortic valve surgery between January 2016 and November 2018: Group 1: Minimally Invasive Technique (N=85) and Group 2 (control) N=89. The approach was hemi-median sternotomy and single-dose cardioplegia in Group 1 and full sternotomy with intermittent crystalloid cardioplegia in control. Serum Syndecan-1 levels were measured by ELISA via arterial line before (T1) and via coronary sinus sample at the end of the cardiopulmonary bypass (CPB) (T2). A right atrial specimen is collected before and at the end of CPB in each case and processed. Cells were incubated with LPS in culture medium with 2% FCS until 24 h and were routinely grown to 80%-90% confluence.

Results: There was not a significant difference between the groups with respect to demographic data, BMI, and the change in the troponin-I levels at T1 and T2 (p = 0.162). Post­operative hemorrhage (Group 1: 260 ± 30 and 895 ± 50 mL in control; p=0.032), respiratory support duration (9.5 ± 2 /18 ± 2 h- p=0.041) and ICU stay (1.2±1 vs 2.4±1 days, p=0.045) were significantly better in the Group 1 vs control. No difference in mortality and major complications was noted. Cross clamp time was 71.4±10 in Group 1 and 85±10 min for control (p=0.042). Serum Syndecan-1 concentration is summarized in Table. Microscopic imaging confirmed the quantitative results of Syndecan-1 dying with significantly better confluences in a minimally invasive group vs. control (11650± 3400 vs16450± 3200 RFU, p=0.028).

Conclusion: Given its importance, the protection of the EG is undoubtedly a promising future target in cardiac operations. Our data underline the impact of minimally invasive techniques verified by cellular function. A possible association between elevated syndecan-1 levels and postoperative complications needs to be clarified in more extensive studies. LEGEND: Quantitative Assessment of EG shedding in groups.

Please feel free to contact Professor Gunaydin and me at any time.


Kevin McCusker Ph.D., MSc., CCP
Assistant Professor of Surgery
New York Medical College
Valhalla, New York 10575

Serdar Gunaydin M.D., Ph.D.
Professor of Surgery
University of Health Sciences
Ankara, Turkey