Microvascular Integrity가 심근 분획 혈류예비력 및관동맥 협착 저항지수에 미치는 영향 = Effects of Microvascular Integrity on the Evaluation of Fractional Flow Reserve and Epicardial Stenosis Resistance Index

다국어 초록 (Multilingual Abstract)

Background and Objectives：The fractional flow reserve (FFR) and the hyperemic epicardial stenosis resistanceindex (hESRI) are known to be useful indexes for evaluating the hemodynamic severity of an epicardial coronarystenosis. However, the influence of the microvascular integrity of the distal segment of the lesion on the FFRand hESRI has not been clearly defined. Subjects and Methods：A total of fifty-nine intermediate lesions of 51patients (mean age: 58±11, 13 infarct-related arteries (IRA)) were studied. The area of stenosis (r-AS%) on theIVUS, the FFR, the coronary flow reserve (CFR) and the hESRI were measured before and after PCI. The hyperemicmicrovascular resistance index (hMVRI) of the distal site of the lesion was measured after PCI. Thestudied lesions were divided into two groups (Group 1, post-stent hMVRI≤2.09 mmHgㆍcm-1ㆍsec, n=38;Group 2, post-stent hMVRI>2.09 mmHgㆍcm-1ㆍsec, n=21; 2.09 is the best cutoff value (BCV) for a CFR of2.5). Results：The FFR and hESRI had excellent correlation with the r-AS% (group 1: r=0.767, p<0.001; r=0.740, p<0.001; group 2: r=0.680, p=0.004; r=0.713, p=0.002, respectively). Although no significant differencewas found in the r-AS% between the two groups, the FFR was significantly lower in group 1 (0.69±0.14 vs.0.79±0.10, p=0.004). In group 1, the BCV of the FFR and hESRI for a r-%AS of 75% were 0.75 and 0.64,respectively, and the concordance rates were 86.8% (κ=0.721, p<0.001) and 81.6% (κ=0.627, p<0.001), respectively.However, in group 2, the BCV of the FFR and hESRI for an r-%AS of 75% were 0.83 and 0.50, respectively,and the concordance rates were 61.9% (κ=0.282, p=0.125) and 66.7% (κ=0.364, p=0.061), respectively.Conclusion：The FFR and hESRI were significantly affected by the microvascular integrity of the distal segmentof the lesion and the anatomic severity of the coronary stenosis was underestimated in the cases with microvasculardysfunction.

국문 초록 (Abstract)

배경 및 목적：FFR(myocardial fractional flow reserve)과 hESRI(hyperemicepicardial stenosis resistance index)는 관동맥 협착의 정도를 기능적으로 평가하는 지수로서 잘 알려져 있으나 이러한 지수들에 대한 microvascular integrity의 영향에 잘 알려져 있지 않다. 본 연구에서는 microvascularintegrity와 관련이 있는 병변 원위부의 hMVRI(hyperemicmicrovascular resistance index)가 FFR과 hESRI로 관동맥 협착의 정도를 평가하는데 어떠한 영향을 주는지 알아보고자 하였다.방 법：허혈성 심질환으로 IVUS에서 r-AS%가 50~90% 사이의환자를 대상으로 중재시술 전ㆍ후 도플러 유도철선 및 압력철선을 이용하여 CFR(coronary flow reserve), FFR 및hESRI를 측정한 51명의 환자, 59 병변을 대상으로 하였다.중재시술 후 hMVRI가 2.09 이하인 군(n=38)과 2.09보다 큰군(n=21)으로 나누어서 FFR, hESRI를 비교하고 양 군에서r-AS% 75%를 예측할 수 있는 임계수치 및 일치율 구하였다. 결 과：전체 병변에서 FFR 및 hESRI는 r-AS%와 의미있는 상관관계를 보였다(r=0.700, p<0.001, r=0.680, p<0.001). Group 1에서 FFR 및 hESRI와 r-AS%와의 상관관계는 각각 r=0.767(p<0.001), 0.740(p<0.001)이었으며 group 2에서는 각각 r=0.680(p=0.004), 0.713(p=0.002)였다. 양 군에서의 r-AS%에서 차이는 없었으나(75.5±9.7% vs. 75.2±9.2%, p=0.882) group 2에서 병변 전ㆍ후의 압력차가 작았고 FFR이 높았다(21.0±11.0 mmHg vs. 31.7±14.5 mmHg,p=0.005; 0.79±0.10 vs. 0.69±0.14, p=0.004, respectively).75%의 r-AS%에 대한 FFR의 임계수치는 group 2에서 0.83로 group 1의 0.75보다 높았고 hESRI의 임계수치는group 2에서 0.50으로 group 1의 0.63보다 낮았다. Group 1에서 75%의 r-AS%에 대한 FFR 및 hESRI의 임계수치에 따른 일치율은 86.8%(κ=0.721, p<0.001), 81.6%(κ=0.627,p<0.001)였으나 group 2에서는 일치율은 각각 61.9%(κ= 0.282, p=0.125), 66.7%(κ=0.364, p=0.061)였다.결 론：관동맥의 협착을 평가할 때 FFR과 hESRI는 hMVRI가 2.09 mmHgㆍcm-1ㆍsec 보다 증가하여 microvascular dysfunction이 있는 경우에는 관동맥 협착의 정도를 저평가 함을
보였다.

참고문헌 (Reference)

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