Published online Mar 26, 2016. doi: 10.4330/wjc.v8.i3.283
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
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.
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.