232. Graft Flow Evaluation with Intraoperative Transit-Time Flow Measurement in Off- Pump versus On-Pump CABG – A propensity score analysis

Graft Flow Evaluation with Intraoperative Transit-Time Flow Measurement in Off- Pump versus On-Pump CABG – a propensity score analysis

Dror B. Leviner, Carlo Maria Rosati, Miriam von Mücke Similon, Andrea Amabile, Naama Schwartz, David P. Taggart, John D. Puskas, on behalf of the "REQUEST" group
*Dror Leviner, MD and Carlo Maria Rosati, MD contributed equally to this work.

Objective: Quality control during coronary artery bypass surgery is imperative for early detection of technical issues. We compared transit-time flow measurement (TTFM) parameters between on pump coronary artery bypass (ONCAB) and off pump (OPCAB) procedures. This was performed with the intention of determining TTFM parameters specific for each type of procedure.

Methods: The database of the multicenter REQUEST study was retrospectively reviewed to compare TTFM parameters between on and off-pump procedures. Only single grafts were included (i.e., no sequential grafts or Y/T grafts). Primary endpoints were mean graft flow (MGF), pulsatility-index (PI), diastolic filling (DF), and backflow (BF) variations for each between-group comparison. To control for between group differences we used propensity score matching (PSM).

Results: Of 1016 patients in the REQUEST registry, 847 had at least a single graft for which TTFM was performed. Of these, 513 patients (60.6%) underwent ONCAB and 334 (39.4%) OPCAB, corresponding to 1050 ONCAB grafts (61.1%) and 669 OPCAB grafts (38.9%). Mean arterial pressure (MAP) during measurements was higher in the OPCAB group. After PSM, we were left with 312 well balanced pairs. In these matched patients, MGF was higher for ONCAB vs. OPCAB (32mL/min vs. 28mL/min, respectively, for all grafts, P<0.001). This trend was true for arterial grafts (ONCAB 30mL/min, OPCAB 27mL/min, P=0.002) as for venous grafts (ONCAB 35mL/min, OPCAB 31mL/min, P=0.0057). PI was lower in the ONCAB group (2.1 vs. 2.3, for all grafts, P<0.001). The BF was also lower in ONCAB than in OPCAB (0.6 vs. 1.3, respectively, for all grafts, P<0.001).

Conclusion: In this retrospective analysis of the REQUEST study, ONCAB MGF was higher than OPCAB MGF and ONCAB PI and BF were lower than OPCAB PI and BF, even though MAP was consistently higher during measurements in the OPCAB patients. This might be attributed to coronary vasodilation caused by global myocardial ischemia during cardioplegic arrest in patients undergoing ONCAB. These data may have clinical implications and raise the question whether specific benchmark TTFM values should be set for ONCAB vs OPACB procedures.

Dror Leviner (1), Carlo Maria Rosati (2), Miriam von Mücke Similon (3), Andrea Amabile (4), Naama Schwartz (5), David Taggart (6), John Puskas (7), (1) Carmel medical center, Haifa, Israel, (2) Mount Sinai Morningside, New York, NY, (3) Sackler School of Medicine New York State/American Program, Tel Aviv University, Tel Aviv, Israel, Tel-Aviv, Israel, (4) Yale New Haven Hospital, Colazza, Novara, (5) Department of Biostatistics, Carmel Medical Center, Haifa, Israel, Haifa, Israel, (6) Oxford University Hospitals, Oxford, Oxfordshire, (7) Mount SInai Morningside (St. Luke's), New York, NY

George Tolis

Invited Discussant

George Tolis, M.D., was born in Chicago, Illinois. He graduated from Yale University summa cum laude with a Bachelor's and a Master's degree in Molecular Biophysics and Biochemistry. Following graduation from Harvard Medical School in 1995, he completed an internship and residency in general surgery at Massachusetts General Hospital and a fellowship in cardiothoracic surgery at Yale-New Haven Hospital. Dr. Tolis then completed an advanced aortic fellowship at Mount Sinai Hospital in New York City under the direction of Dr. Randall Griepp. 

Dr. Tolis worked at Lenox Hill Hospital in New York City as chief of aortic surgery, at St. Elizabeth's Medical Center as chief of the Division of Cardiothoracic Surgery and at Massachusetts General Hospital as surgical director of coronary bypass surgery.  He joined Brigham and Women’s Hospital in 2021 as Section Chief of Coronary and General Cardiac Surgery as well as Network Director of Cardiac Surgery.

His clinical interests include surgical education, multi-arterial coronary artery bypass grafting and coronary endarterectomy, surgery for endocarditis, aortic root and arch surgery, complex reoperations and surgery to address complications from percutaneous devices (coronary stents, percutaneous valves and implants).

He is an amateur woodworker and a concert pianist.

Dror Leviner

Abstract Presenter

 

Studied medicine in the Hebrew university in Jerusalem. Underwent 6 years of dedicated cardiac surgery training in Rabin Medical center. Then underwent a two-year clinical fellowship at Mount Sinai hospital in New York city, under the supervision of Dr. David Adams and Dr. John Puskas, among others.

For the past three years, since returning from fellowship, Dr. Leviner is an attending cardiac surgeon at Carmel Medical Center in Haifa, Israel. His focus is coronary artery bypass grafting, including use of multiple arterial grafts and complex grafting, and mitral valve surgery. He is also highly active in the peri-operative care of patients with the aim of improving operative results and reducing post-operative complications.

He is involved in clinical research with a growing number of publications in recent years in peer reviewed journals.

Specialties: Adult Cardiac, Coronary, Treatment/Procedure/Operation/Surgery, Coronary Disease, CABG