Ciró E, Maron B J, Bonow R O, Cannon R O, Epstein S E
Am J Cardiol. 1984 Apr 1;53(8):1103-9. doi: 10.1016/0002-9149(84)90645-3.
Spontaneous and persistent changes in left ventricular (LV) outflow gradient have been observed occasionally in patients with hypertrophic cardiomyopathy (HC). However, the significance and frequency of such hemodynamic alterations have not been established. In this study, the serial preoperative hemodynamic status of 409 patients with HC was analyzed. Basal LV outflow tract obstruction either spontaneously appeared (or increased) or disappeared (or decreased) in 19 nonoperated patients (about 5%). Changes in hemodynamic state were shown by serial cardiac catheterization in 17 patients and by catheterization and M-mode echocardiography in 2 patients. In most patients (12 of 19), subaortic obstruction under basal conditions appeared or increased; 8 became more symptomatic and in 4 the condition remained stable. Reduction or loss of LV outflow gradient occurred in 7 patients; in 5 of these the condition deteriorated clinically and in 2 it did not change. Hence, in 13 of the 19 patients (70%), spontaneous changes in the magnitude of the basal LV outflow gradient were associated with symptomatic progression. The mechanism of the decrease or disappearance of subaortic obstruction in those patients who deteriorated clinically appeared to be related in 4 patients to impaired global and/or segmental LV function. Chronic atrial fibrillation probably contributed to the worsening clinical condition in 2 of these patients as well as in 2 others. In conclusion, substantial changes in the magnitude of basal subaortic obstruction may occur in a small proportion of patients with HC as part of the natural history of their disease, and such hemodynamic alterations are usually associated with clinical deterioration. It is exceedingly rare for the hemodynamic state of a patient with HC to change from totally nonobstructive to obstructive or vice versa, because such patients usually retain the capacity to generate gradients with provocative maneuvers.
肥厚型心肌病（HC）患者偶尔会出现左心室（LV）流出道梯度的自发且持续变化。然而，这种血流动力学改变的意义和频率尚未明确。在本研究中，分析了409例HC患者术前的连续血流动力学状态。19例未接受手术的患者（约5%）出现基础LV流出道梗阻自发出现（或加重）或消失（或减轻）。17例患者通过连续心脏导管检查显示血流动力学状态变化，2例患者通过导管检查和M型超声心动图显示。在大多数患者（19例中的12例）中，基础状态下主动脉下梗阻出现或加重；8例症状加重，4例病情保持稳定。7例患者LV流出道梯度降低或消失；其中5例临床病情恶化，2例未改变。因此，19例患者中有13例（70%）基础LV流出道梯度大小的自发变化与症状进展相关。临床病情恶化的患者中，主动脉下梗阻减轻或消失的机制在4例患者中似乎与整体和/或节段性LV功能受损有关。慢性心房颤动可能导致其中2例患者以及另外2例患者临床病情恶化。总之，一小部分HC患者可能会出现基础主动脉下梗阻大小的显著变化，这是其疾病自然史的一部分，且这种血流动力学改变通常与临床恶化相关。HC患者的血流动力学状态从完全无梗阻变为梗阻或反之的情况极为罕见，因为这类患者通常保留通过激发动作产生梯度的能力。
