Clinical Trials Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Mar 26, 2016; 8(3): 283-292
Published online Mar 26, 2016. doi: 10.4330/wjc.v8.i3.283
Clinical outcomes of combined flow-pressure drop measurements using newly developed diagnostic endpoint: Pressure drop coefficient in patients with coronary artery dysfunction
Mohamed A Effat, Srikara Viswanath Peelukhana, Rupak K Banerjee
Mohamed A Effat, Division of Cardiovascular Health and Diseases, University of Cincinnati Medical Center, Veteran Affairs Medical Center, Cincinnati, OH 45221, United States
Srikara Viswanath Peelukhana, Rupak K Banerjee, Research Services, Veteran Affairs Medical Center, Cincinnati, OH 45220, United States
Srikara Viswanath Peelukhana, Rupak K Banerjee, Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, OH 45221, United States
Author contributions: Effat MA, Peelukhana SV, Banerjee RK designed the research and wrote the paper; Effat MA performed the interventions; Peelukhana SV performed the data analysis; Banerjee RK assimilated the data.
Supported by VA Merit Review Grant (I01CX000342-01), Department of Veteran Affairs.
Institutional review board statement: The study protocol was approved by the institutional review board at University of Cincinnati (UC) and the research and development committee at the Cincinnati Veteran Affairs Medical Center (CVAMC).
Clinical trial registration statement: The study was registered with Clinicaltrials.gov. The registration identification number is NCT01719016.
Informed consent statement: All study participants, provided informed written consent prior to the study enrolment.
Conflict-of-interest statement: The authors report no financial relationships or conflicts of interest regarding the content herein.
Data sharing statement: Technical details and statistical methods are available with the corresponding author at rupak.banerjee@uc.edu.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Rupak K Banerjee, PhD, PE, Department of Mechanical and Materials Engineering, University of Cincinnati, 598 Rhodes Hall, PO Box 0072, Cincinnati, OH 45221, United States. rupak.banerjee@uc.edu
Telephone: +1-513-5562124 Fax: +1-513-5563390
Received: July 31, 2015
Peer-review started: August 1, 2015
First decision: September 29, 2015
Revised: November 2, 2015
Accepted: December 29, 2015
Article in press: January 4, 2016
Published online: March 26, 2016
Processing time: 234 Days and 20.1 Hours
Abstract

AIM: To combine pressure and flow parameter, pressure drop coefficient (CDP) will result in better clinical outcomes in comparison to the fractional flow reserve (FFR) group.

METHODS: To test this hypothesis, a comparison was made between the FFR < 0.75 and CDP > 27.9 groups in this study, for the major adverse cardiac events [major adverse cardiac events (MACE): Primary outcome] and patients’ quality of life (secondary outcome). Further, a comparison was also made between the survival curves for the FFR < 0.75 and CDP > 27.9 groups. Two-tailed χ2 test proportions were performed for the comparison of primary and secondary outcomes. Kaplan-Meier survival analysis was performed to compare the survival curves of FFR < 0.75 and CDP > 27.9 groups (MedcalcV10.2, Mariakerke, Belgium). Results were considered statistically significant for P < 0.05.

RESULTS: The primary outcomes (%MACE) in the FFR < 0.75 group (20%, 4 out of 20) was not statistically different (P = 0.24) from the %MACE occurring in CDP > 27.9 group (8.57%, 2 out of 35). Noteworthy is the reduction in the %MACE in the CDP > 27.9 group, in comparison to the FFR < 0.75 group. Further, the secondary outcomes were not statistically significant between the FFR < 0.75 and CDP > 27.9 groups. Survival analysis results suggest that the survival time for the CDP > 27.9 group (n = 35) is significantly higher (P = 0.048) in comparison to the survival time for the FFR < 0.75 group (n = 20). The results remained similar for a FFR = 0.80 cut-off.

CONCLUSION: Based on the above, CDP could prove to be a better diagnostic end-point for clinical revascularization decision-making in the cardiac catheterization laboratories.

Keywords: Pressure drop coefficient; Interventional cardiology; Intermediate coronary stenosis

Core tip: In the case of intermediate coronary stenosis, fractional flow reserve (FFR) is traditionally used as a functional end-point for interventional decision making in a cardiac catheterization laboratory. In this outcomes study, it was purported that pressure drop coefficient could prove to be a better clinical end-point for decision-making in comparison to the FFR.