Ramamurthy Muralidharan Thoddi, Balakrishnan Vinod Kumar, Vallivedu Mano Vikash, Senguttuvan Nagendra Boopathy, Manokar Panchanatham, Sankaran Ramesh, Sadhanandham Shanmugasundaram, Balasubramaniyan Jayanthi Venkata, Rathinasamy Jebaraj, Krishnamurthy Preetam, Sundaram Sandhya, Murthy Jayanthi Sri Sathiyanarayana, Thanikachalam Sadagopan, Pogwizd Steven, Hoidal John R, Namakkal-Soorappan Rajasekaran
Department of Cardiology, Sri Ramachandra Medical University & Research Institute, Chennai, India.
Comprehensive Cardiovascular Center, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
Cardiol Cardiovasc Med. 2023;7(2):108-116. Epub 2023 Apr 4.
To compare the fractional flow reserve (FFR) and diastolic hyperemia-free ratio (DFR) measurements in a population with intermediate coronary artery stenosis and improve the diagnosis.
Visual assessment of coronary artery stenosis severity, particularly in intermediate lesions, is prone to errors in decision-making. FFR provides a reliable assessment of functional severity in these cases but requires hyperemia induction by adenosine, which has side effects and increased cost. DFR is a novel hyperemia-independent index, which could be used as an alternative to adenosine-based hyperemia induction.
Between September 2019 to March 2020, 25 patients with 38 intermediate coronary stenotic lesions were included in the study. All patients underwent assessment of whole cycle Pd/Pa (ratio of distal coronary pressure to proximal aortic pressure), DFR and FFR. Mean whole cycle Pd/Pa, DFR and FFR were 0.93±0.06, 0.88±0.09, and 0.85±0.08, respectively. A significant positive correlation between DFR and FFR [r = 0.74; p<0.001] was observed. Receiver operating characteristic analysis showed an area under the curve of 0.90. DFR-only strategy with a treatment cut-off of ≤0.89 showed a diagnostic agreement with the FFR-only strategy in 74% of lesions, with a sensitivity of 54%, specificity of 82%, a positive predictive value of 60%, and a negative predictive value of 79%.
Real-time DFR measurements show a clinically reliable correlation with FFR. Hence, using DFR is likely to avoid adenosine administration as well as reduce the cost and procedural time. Further studies with a larger sample size would be ideal to evaluate specific cut-off values and endpoints.
比较中度冠状动脉狭窄人群的血流储备分数（FFR）和无舒张期充血比率（DFR）测量值，以改善诊断。
冠状动脉狭窄严重程度的视觉评估，尤其是在中度病变中，在决策时容易出错。FFR可对这些病例的功能严重程度进行可靠评估，但需要通过腺苷诱发充血，这有副作用且成本增加。DFR是一种新型的非充血依赖性指标，可作为基于腺苷的充血诱发方法的替代方法。
2019年9月至2020年3月期间，25例患有38处中度冠状动脉狭窄病变的患者纳入研究。所有患者均接受了全周期Pd/Pa（冠状动脉远端压力与主动脉近端压力之比）、DFR和FFR评估。全周期Pd/Pa、DFR和FFR的平均值分别为0.93±0.06、0.88±0.09和0.85±0.08。观察到DFR与FFR之间存在显著正相关[r = 0.74；p<0.001]。受试者工作特征分析显示曲线下面积为0.90。治疗截断值≤0.89的仅DFR策略与仅FFR策略在74%的病变中显示出诊断一致性，敏感性为54%，特异性为82%，阳性预测值为60%，阴性预测值为79%。
实时DFR测量显示与FFR具有临床可靠的相关性。因此，使用DFR可能避免腺苷给药，同时降低成本和操作时间。进行更大样本量的进一步研究以评估特定的截断值和终点将是理想的。
