肥厚型心肌病患者的微血管功能障碍、心肌缺血和心力衰竭进展。
Microvascular dysfunction, myocardial ischemia, and progression to heart failure in patients with hypertrophic cardiomyopathy.
机构信息
Regional Referral Center for Myocardial Diseases, Department of Cardiology, Azienda Ospedaliera Universitaria Careggi, Florence, Italy.
出版信息
J Cardiovasc Transl Res. 2009 Dec;2(4):452-61. doi: 10.1007/s12265-009-9142-5. Epub 2009 Nov 3.
Microvascular dysfunction can be demonstrated in most patients with hypertrophic cardiomyopathy (HCM), both in the hypertrophied and nonhypertrophied myocardial walls, mostly due to intimal and medial hyperplasia of the intramural coronary arteries and subsequent lumen reduction. As a consequence, regional myocardial ischemia may be triggered by exercise, increased heart rate, or arrhythmias, in areas which are unable to increase myocardial blood flow. In patients with HCM, microvascular dysfunction leading to severe myocardial hypoperfusion during maximal hyperemia represents a strong predictor of unfavorable outcome, left ventricular remodeling with progressive wall thinning, left ventricular dysfunction, and heart failure. Accurate quantitative assessment of microvascular dysfunction and myocardial ischemia is not easily feasible in clinical practice. Although signs of inducible myocardial ischemia may be detected by electrocardiogram, echocardiography, or myocardial scintigraphy, the vasodilator response to dipyridamole by positron emission tomography is considered the method of choice for the assessment of maximal regional and global flow. Cardiac magnetic resonance provides further information, by late gadolinium enhancement (LGE), which may show areas where replacement fibrosis has occurred following microvascular ischemia and focal necrosis. LGE areas colocalize with severe regional microvascular dysfunction, are associated with increased prevalence of ventricular arrhythmias, and show more extensive distribution in the late stages of the disease, when heart failure is the dominant feature. The present review aims to provide a concise overview of the available evidence of microvascular dysfunction and ischemia eventually leading to disease progression and heart failure in HCM patients.
微血管功能障碍可在大多数肥厚型心肌病(HCM)患者中得到证实,无论是在心肌肥厚和非肥厚的壁中,主要是由于心肌内冠状动脉的内膜和中膜增生以及随后的管腔缩小。因此,在无法增加心肌血流量的区域,运动、心率增加或心律失常可能引发局部心肌缺血。在 HCM 患者中,导致最大充血时严重心肌灌注不足的微血管功能障碍是不良预后的强烈预测因素,表现为左心室重构伴进行性壁变薄、左心室功能障碍和心力衰竭。微血管功能障碍和心肌缺血的准确定量评估在临床实践中并不容易实现。尽管心电图、超声心动图或心肌闪烁显像术可能检测到可诱导性心肌缺血的迹象,但正电子发射断层扫描(PET)下双嘧达莫的血管扩张反应被认为是评估最大区域和整体血流的首选方法。心脏磁共振(CMR)通过晚期钆增强(LGE)提供了进一步的信息,它可能显示出在微血管缺血和局灶性坏死发生后替代纤维化的区域。LGE 区域与严重的局部微血管功能障碍共存,与室性心律失常的发生率增加相关,并在疾病的晚期(当心力衰竭是主要特征时)更广泛地分布。本综述旨在提供微血管功能障碍和缺血最终导致 HCM 患者疾病进展和心力衰竭的现有证据的简要概述。