Erbel Christian, Mukhammadaminova Nodira, Gleissner Christian A, Osman Nael F, Hofmann Nina P, Steuer Christian, Akhavanpoor Mohammadreza, Wangler Susanne, Celik Sultan, Doesch Andreas O, Voss Andreas, Buss Sebastian J, Schnabel Philipp A, Katus Hugo A, Korosoglou Grigorios
Department of Cardiology, University Hospital Heidelberg, Heidelberg, Germany.
Myocardial Solutions, Inc., Morrisville, North Carolina.
JACC Cardiovasc Imaging. 2016 Mar;9(3):255-66. doi: 10.1016/j.jcmg.2015.10.012.
This study sought to evaluate myocardial perfusion reserve index (MPRI) and diastolic strain rate, both assessed by cardiac magnetic resonance (CMR) as a noninvasive tool for the detection of microvasculopathy.
Long-term survival of cardiac allograft recipients is limited primarily by cancer and cardiac allograft vasculopathy (CAV). Besides epicardial CAV, diagnosed by coronary angiography, stenotic microvasculopathy was found to be an additional independent risk factor for survival after heart transplantation.
Sixty-three consecutive heart transplant recipients who underwent CMR, coronary angiography, and myocardial biopsy were enrolled. Stenotic vasculopathy in microvessels was considered in myocardial biopsies by immunohistochemistry and CAV was graded during coronary angiography according to International Society of Heart and Lung Transplantation criteria. In addition, by CMR microvasculopathy was assessed by myocardial perfusion reserve during pharmacologic hyperemia with adenosine and strain-encoded magnetic resonance using a modified spatial modulation of magnetization tagging pulse sequence in all patients.
Decreasing MPRI and diastolic strain rates were observed in patients with decreasing microvessel luminal radius to wall thickness ratio and decreasing capillary density (r = 0.45 and r = 0.61 for MPRI and r = 0.50 and r = 0.38 for diastolic strain rate, respectively; p < 0.005 for all). Using multivariable analysis, both MPRI and diastolic strain rate were robust predictors of stenotic microvasculopathy, independent of age, organ age, and CAV by International Society of Heart and Lung Transplantation criteria (hazard ratio: 0.07, p = 0.006 for MPRI; hazard ratio: 0.91, p = 0.002 for diastolic strain rate). Patients without stenotic microvasculopathy in the presence of no or mild CAV (n = 36) exhibited significantly higher median survival free of events, compared with patients with stenotic microvasculopathy in the presence of no or mild CAV (n = 18; p = 0.04 by log rank).
CMR represents a valuable noninvasive diagnostic tool, which may be used for the early detection of transplant microvasculopathy before the manifestation of CAV during surveillance coronary angiographic procedures.
本研究旨在评估心肌灌注储备指数（MPRI）和舒张期应变率，二者均通过心脏磁共振成像（CMR）进行评估，作为检测微血管病变的一种非侵入性工具。
心脏移植受者的长期生存主要受癌症和心脏移植血管病变（CAV）的限制。除了通过冠状动脉造影诊断的心外膜CAV外，狭窄性微血管病变被发现是心脏移植后生存的另一个独立危险因素。
纳入63例连续接受CMR、冠状动脉造影和心肌活检的心脏移植受者。通过免疫组织化学在心肌活检中评估微血管的狭窄性血管病变，并根据国际心肺移植学会标准在冠状动脉造影期间对CAV进行分级。此外，在所有患者中，通过CMR在使用腺苷进行药物性充血期间通过心肌灌注储备评估微血管病变，并使用改良的磁化标记脉冲序列的空间调制进行应变编码磁共振成像。
在微血管腔半径与壁厚比值降低和毛细血管密度降低的患者中，观察到MPRI和舒张期应变率降低（MPRI的r分别为0.45和0.61，舒张期应变率的r分别为0.50和0.38；所有p<0.005）。使用多变量分析，根据国际心肺移植学会标准，MPRI和舒张期应变率均是狭窄性微血管病变的有力预测指标，独立于年龄、器官年龄和CAV（风险比：MPRI为0.07，p=0.006；舒张期应变率为0.91，p=0.002）。与无或轻度CAV且存在狭窄性微血管病变的患者（n=18）相比，无或轻度CAV且无狭窄性微血管病变的患者（n=36）的无事件中位生存期显著更长（对数秩检验p=0.04）。
CMR是一种有价值的非侵入性诊断工具，可用于在监测冠状动脉造影过程中CAV出现之前早期检测移植微血管病变。
