Section of Cardiology, Department of Medicine, University of Chicago Pritzker School of Medicine , Chicago, Illinois.
Advocate Healthcare, Chicago, Illinois.
Am J Physiol Heart Circ Physiol. 2018 May 1;314(5):H1033-H1042. doi: 10.1152/ajpheart.00680.2017. Epub 2018 Feb 9.
There are multiple proposed mechanisms for the pathophysiology of heart failure (HF) with preserved ejection fraction (HFpEF). We hypothesized that coronary microvascular dysfunction is common in these patients. In a prospective, observational study, patients undergoing cardiac catheterization with HFpEF [left ventricular (LV) ejection fraction ≥ 50% and with clinical HF] were compared with similar patients without HFpEF. Patients with ≥50% stenosis were excluded, and coronary flow reserve (CFR) and the index of microvascular resistance (IMR) were measured after adenosine administration using a guidewire, with CFR ≤ 2 and IMR ≥ 23 being abnormal. Baseline characteristics and CFR and IMR were compared in 30 HFpEF patients and 14 control subjects. Compared with control subjects, HFpEF patients were older (65.4 ± 9.6 vs. 55.1 ± 3.1 yr, P < 0.01), had higher numbers of comorbidities (4.4 ± 1.5 vs. 2.6 ± 1.9, P = 0.002), had higher median B-type natriuretic peptide [161 (interquartile range: 75-511) pg/dl vs. 37 (interquartile range: 18.5-111) pg/dl, P < 0.01], and had higher LV end-diastolic pressure (17.8 ± 4.2 vs. 8.4 ± 4.2, P < 0.01). HFpEF patients had lower CFR (2.55 ± 1.60 vs. 3.84 ± 1.89, P = 0.024) and higher IMR (26.7 ± 10.3 vs. 19.7 ± 9.7 units, P = 0.037) than control subjects. Most (71.4%) control subjects had normal coronary physiology, whereas 36.7% of HFpEF patients had both abnormal CFR and IMR and another 36.7% had either abnormal CFR or IMR. In conclusion, this is the first study that has reported invasively determined CFR and IMR in HFpEF patients. We demonstrated the presence of four distinct coronary physiology groups in HFpEF patients. Investigation into the potential mechanisms for these findings is needed. NEW & NOTEWORTHY In this prospective observational study of patients with heart failure with preserved ejection fraction (HFpEF), we found that patients with HFpEF had more abnormalities of coronary flow and resistance than asymptomatic control patients, indicating that coronary microvascular dysfunction may play a role in the HFpEF disease process.
存在多种提出的机制用于射血分数保留的心力衰竭（HFpEF）的病理生理学。我们假设冠状动脉微血管功能障碍在这些患者中很常见。在一项前瞻性观察性研究中，接受 HFpEF 心导管检查的患者（左心室 [LV] 射血分数≥50% 且有临床 HF）与无 HFpEF 的类似患者进行比较。排除≥50%狭窄的患者，并在给予腺苷后使用导丝测量冠状动脉血流储备（CFR）和微血管阻力指数（IMR），CFR≤2 和 IMR≥23 为异常。比较 30 例 HFpEF 患者和 14 例对照者的基线特征和 CFR 和 IMR。与对照组相比，HFpEF 患者年龄更大（65.4±9.6 岁 vs. 55.1±3.1 岁，P<0.01），合并症更多（4.4±1.5 例 vs. 2.6±1.9 例，P=0.002），中位 B 型利钠肽水平更高[161（四分位距：75-511）pg/dl vs. 37（四分位距：18.5-111）pg/dl，P<0.01]，LV 舒张末期压更高（17.8±4.2mmHg vs. 8.4±4.2mmHg，P<0.01）。HFpEF 患者的 CFR（2.55±1.60 vs. 3.84±1.89，P=0.024）和 IMR（26.7±10.3 vs. 19.7±9.7 单位，P=0.037）均低于对照组。大多数（71.4%）对照组患者的冠状动脉生理正常，而 36.7%的 HFpEF 患者同时存在 CFR 和 IMR 异常，另外 36.7%的患者存在 CFR 或 IMR 异常。总之，这是第一项报告 HFpEF 患者有创性测定 CFR 和 IMR 的研究。我们在 HFpEF 患者中发现了四个不同的冠状动脉生理组。需要研究这些发现的潜在机制。 新的和值得注意的 在这项对射血分数保留的心力衰竭（HFpEF）患者的前瞻性观察性研究中，我们发现 HFpEF 患者的冠状动脉血流和阻力异常比无症状对照患者更常见，这表明冠状动脉微血管功能障碍可能在 HFpEF 发病机制中起作用。
