Institute for Advanced Biomedical Technologies, "G. d'Annunzio" University, Via Luigi Polacchi, 11 - 66100 Chieti, Italy.
Department of Neuroscience, Imaging and Clinical Sciences, "G. d'Annunzio" University, Via dei Vestini. 31 - 66100 Chieti, Italy.
Eur Heart J Cardiovasc Imaging. 2018 Aug 1;19(8):896-904. doi: 10.1093/ehjci/jex214.
Pulmonary blood volume (PBV) is a novel clinical application of cardiovascular magnetic resonance (CMR) imaging for the quantitative grading of haemodynamic congestion. In this study, we aimed to assess the prognostic value of PBV in a cohort of outpatients with chronic heart failure (HF).
One hundred and twelve consecutive patients (91 men, 67 ± 12 years) and 53 age- and sex-matched healthy controls underwent echocardiography and contrast-enhanced CMR. PBV was calculated as the product of stroke volume and the number of cardiac cycles for an intravenous bolus of gadolinium contrast to pass through the pulmonary circulation determined by first-pass perfusion imaging. Compared with healthy controls, HF outpatients showed significantly higher PBV index (PBVI, 308 ± 92 vs. 373 ± 175, mL/m2, P = 0.012) and pulmonary transit time (6.8 ± 1.8 vs. 9.5 ± 4 s, P ≤0.001). During a median follow-up of 26 ± 17 months, 27 patients (24%) reached the composite end point of cardiovascular death, HF hospitalization, or sustained ventricular arrhythmias/appropriate implantable cardioverter-defibrillator intervention. Using a cut-off point of PBVI >492 mL/m2, corresponding to two standard deviations above the mean of healthy controls, event-free survival was significantly lower in patients with higher PBVI (P < 0.001). At multivariable-adjusted Cox regression analysis, PBVI was an independent predictor of the composite cardiovascular end point (per 10% increase hazard ratio 1.31, 95% confidence interval: 1.02-1.69, P = 0.03).
PBVI is a novel application of perfusion CMR potentially useful to quantitatively determine haemodynamic congestion as a surrogate marker of left ventricular diastolic dysfunction. PBVI might prove to be helpful in stratifying the prognosis of asymptomatic or mildly symptomatic patients with left ventricular dysfunction.
肺血容量（PBV）是心血管磁共振成像（CMR）在定量评估血流动力学充血方面的一项新的临床应用。本研究旨在评估 PBV 在慢性心力衰竭（HF）门诊患者队列中的预后价值。
112 例连续患者（91 名男性，67±12 岁）和 53 名年龄和性别匹配的健康对照者接受了超声心动图和对比增强 CMR 检查。通过首过灌注成像确定静脉注射钆对比剂通过肺循环的心脏周期数，将 PBV 计算为每搏量与该数的乘积。与健康对照组相比，HF 门诊患者的 PBV 指数（PBVI，308±92 比 373±175，mL/m2，P=0.012）和肺通过时间（6.8±1.8 比 9.5±4 s，P≤0.001）明显更高。在中位随访 26±17 个月期间，27 名患者（24%）达到心血管死亡、HF 住院或持续性室性心律失常/适当植入式心脏复律除颤器干预的复合终点。使用 PBVI>492 mL/m2 的截止点，对应于健康对照组平均值的两个标准差以上，PBVI 较高的患者的无事件生存显著降低（P<0.001）。在多变量调整的 Cox 回归分析中，PBVI 是复合心血管终点的独立预测因子（每增加 10%，危险比 1.31，95%置信区间：1.02-1.69，P=0.03）。
PBVI 是灌注 CMR 的一种新应用，可能有助于定量确定血流动力学充血，作为左心室舒张功能障碍的替代标志物。PBVI 可能有助于对无症状或轻度症状的左心室功能障碍患者进行预后分层。
