Positron emission tomography (PET) has demonstrated utility for diagnostic and prognostic assessment of cardiac allograft vasculopathy (CAV) but has not been evaluated in the first year after transplant. The authors sought to evaluate CAV at 1 year by PET myocardial blood flow (MBF) quantification. Adults at 2 institutions enrolled between January 2018 and March 2021 underwent prospective 3-month (baseline) and 12-month (follow-up) post-transplant PET, endomyocardial biopsy, and intravascular ultrasound examination. Epicardial CAV was assessed by intravascular ultrasound percent intimal volume (PIV) and microvascular CAV by endomyocardial biopsy. A total of 136 PET studies from 74 patients were analyzed. At 12 months, median PIV increased 5.6% (95% CI: 3.6%-7.1%) with no change in microvascular CAV incidence (baseline: 31% vs follow-up: 38%; 0.406) and persistent microvascular disease in 13% of patients. Median capillary density increased 30 capillaries/mm (95% CI: −6 to 79 capillaries/mm). PET myocardial flow reserve (2.5 ± 0.7 vs 2.9 ± 0.8; 0.001) and stress MBF (2.7 ± 0.6 vs 2.9 ± 0.6; 0.008) increased, and coronary vascular resistance (CVR) (49 ± 13 vs 47 ± 11; 0.214) was unchanged. At 12 months, PET and PIV had modest correlation (stress MBF: = −0.35; CVR: = 0.33), with lower stress MBF and higher CVR across increasing PIV tertiles (all 0.05). Receiver-operating characteristic curves for CAV defined by upper-tertile PIV showed areas under the curve of 0.74 for stress MBF and 0.73 for CVR. The 1-year post-transplant PET MBF is associated with epicardial CAV, supporting potential use for early noninvasive CAV assessment. (Early Post Transplant Cardiac Allograft Vasculopahty [ECAV]; )

中文翻译：

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心脏 PET 心肌血流定量评估早期心脏同种异体移植血管病变


正电子发射断层扫描 (PET) 已被证明可用于心脏同种异体移植血管病变 (CAV) 的诊断和预后评估，但尚未在移植后第一年进行评估。作者试图通过 PET 心肌血流 (MBF) 定量来评估 1 年时的 CAV。 2018 年 1 月至 2021 年 3 月期间入组的 2 家机构的成年人接受了前瞻性 3 个月（基线）和 12 个月（随访）移植后 PET、心内膜心肌活检和血管内超声检查。心外膜 CAV 通过血管内超声内膜体积百分比 (PIV) 评估，微血管 CAV 通过心内膜心肌活检评估。总共分析了 74 名患者的 136 项 PET 研究。 12 个月时，中位 PIV 增加了 5.6%（95% CI：3.6%-7.1%），而微血管 CAV 发生率没有变化（基线：31% vs 随访：38%；0.406），13% 的患者存在持续性微血管疾病患者。中位毛细血管密度增加了 30 根毛细血管/毫米（95% CI：-6 至 79 根毛细血管/毫米）。 PET 心肌血流储备 (2.5 ± 0.7 vs 2.9 ± 0.8; 0.001) 和应激 MBF (2.7 ± 0.6 vs 2.9 ± 0.6; 0.008) 增加，冠状血管阻力 (CVR) (49 ± 13 vs 47 ± 11; 0.214)不变。 12 个月时，PET 和 PIV 具有适度的相关性（压力 MBF：= −0.35；CVR：= 0.33），随着 PIV 三分位数的增加，压力 MBF 较低，CVR 较高（均为 0.05）。由上三分位数 PIV 定义的 CAV 接受者操作特征曲线显示，应力 MBF 的曲线下面积为 0.74，CVR 的曲线下面积为 0.73。移植后 1 年 PET MBF 与心外膜 CAV 相关，支持早期无创 CAV 评估的潜在用途。 （移植后早期心脏同种异体移植血管病变 [ECAV]；）