Hieda Michinari, Parker Joshua, Rajabi Tanya, Fujimoto Naoki, Bhella Paul S, Prasad Anand, Hastings Jeffrey L, Sarma Satyam, Levine Benjamin D
Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center, Texas.
Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center, Texas.
Am J Cardiol. 2018 Mar 1;121(5):609-614. doi: 10.1016/j.amjcard.2017.11.033. Epub 2017 Dec 11.
Elevated left ventricular (LV) filling pressures are commonly reported in patients with heart failure with preserved ejection fraction (HFpEF) and are associated with impaired relaxation in diastole. Relaxation has been assessed by Doppler, but the methods for doing so are indirect and heavily influenced by loading conditions. The aim of this study is to assess LV volume-time relation in patients with HFpEF, when correcting for left atrial driving pressure and chamber size, using cardiac magnetic resonance imaging (cMRI). Cine short-axis views by cMRI (1.5T-magnet) at 26 Hz were used for measurement of LV volume. We compared the following diastolic parameters: peak filling rate/end-diastolic volume (PFR/EDV); PFR/EDV/pulmonary capillary wedge pressure (PFR/EDV/PCWP); time to PFR (TPFR); and %TPFR for cardiac cycle calculated by cMRI between patients with HFpEF (n = 10, 73 ± 7 years) and age-matched controls (n = 12, 70 ± 3 years). PCWP was significantly greater in the HFpEF group than in controls (HFpEF vs controls: 15.6 ± 5.2 vs 11.2 ± 1.3 mmHg, p = 0.0092). PFR/EDV was significantly slower in the HFpEF group than in controls (2.68 ± 0.85 vs 3.59 ± 0.87/s, p = 0.03), and was nearly 50% slower when corrected for left atrial driving pressure: PFR/EDV/PCWP (0.18 ± 0.07 vs 0.33 ± 0.10/s/mmHg, p = 0.002). In addition, TPFR (246 ± 17.2 vs 188 ± 15.7 ms, p = 0.04) and %TPFR of cardiac cycle (36.4 ± 10.4 vs 25.6 ± 5.9%, p = 0.012) were significantly longer in the HFpEF group than in controls. Patients with HFpEF have an abnormal volume-time relation, including lower PFR/EDV (PFR/EDV/PCWP) and prolonged TPFR, due to the impairment of active relaxation during early diastole.
射血分数保留的心力衰竭（HFpEF）患者中，左心室（LV）充盈压升高较为常见，且与舒张期松弛受损有关。舒张功能已通过多普勒进行评估，但评估方法是间接的，且受负荷条件影响较大。本研究的目的是使用心脏磁共振成像（cMRI），在校正左心房驱动压力和心室大小的情况下，评估HFpEF患者的左心室容积-时间关系。通过cMRI（1.5T磁体）以26Hz采集的电影短轴视图用于测量左心室容积。我们比较了以下舒张期参数：峰值充盈率/舒张末期容积（PFR/EDV）；PFR/EDV/肺毛细血管楔压（PFR/EDV/PCWP）；达到PFR的时间（TPFR）；以及通过cMRI计算的HFpEF患者（n = 10，73±7岁）和年龄匹配对照组（n = 12，70±3岁）心动周期的%TPFR。HFpEF组的PCWP显著高于对照组（HFpEF组与对照组：15.6±5.2 vs 11.2±1.3mmHg，p = 0.0092）。HFpEF组的PFR/EDV显著慢于对照组（2.68±0.85 vs 3.59±0.87/s，p = 0.03），在校正左心房驱动压力后慢近50%：PFR/EDV/PCWP（0.18±0.07 vs 0.33±0.10/s/mmHg，p = 0.002）。此外，HFpEF组的TPFR（246±17.2 vs 188±15.7ms，p = 0.04）和心动周期的%TPFR（36.4±10.4 vs 25.6±5.9%，p = 0.012）显著长于对照组。HFpEF患者存在异常的容积-时间关系，包括较低的PFR/EDV（PFR/EDV/PCWP）和延长的TPFR，这是由于舒张早期主动松弛功能受损所致。
