Ganau A, Devereux R B, Pickering T G, Roman M J, Schnall P L, Santucci S, Spitzer M C, Laragh J H
Cardiovascular and Hypertension Center, New York Hospital-Cornell Medical Center, NY 10021.
Circulation. 1990 Jan;81(1):25-36. doi: 10.1161/01.cir.81.1.25.
The weak relation of systolic blood pressure to left ventricular mass in hypertensive patients is often interpreted as evidence of nonhemodynamic stimuli to muscle growth. To test the hypothesis that left ventricular chamber size, reflecting hemodynamic volume load and myocardial contractility, influences the development of left ventricular hypertrophy in hypertension, we studied actual and theoretic relations of left ventricular mass to left ventricular diastolic chamber volume, pressure and volume load, and an index of contractility. Data were obtained from independently measured M-mode and two-dimensional echocardiograms in 50 normal subjects and 50 untreated patients with essential hypertension. Two indices of overall left ventricular load were assessed: total load (systolic blood pressure x left ventricular endocardial surface area) and peak meridional force (systolic blood pressure x left ventricular cross sectional area). A theoretically optimal left ventricular mass, allowing each subject to achieve mean normal peak stress, was calculated as a function of systolic blood pressure and M-mode left ventricular end-diastolic diameter. Left ventricular mass measured by M-mode echo correlated better with two-dimensional echocardiogram derived left ventricular end-diastolic volume (r = 0.56, p less than 0.001) than with systolic blood pressure (r = 0.45, p less than 0.001) and best with total load or peak meridional force (r = 0.68 and 0.70, p less than 0.001). In multivariate analysis both end-diastolic volume and blood pressure were independent predictors of systolic mass (p less than 0.001) and explained most of its variability (R = 0.75, p less than 0.001). Theoretically optimal left ventricular mass was more closely related to end-diastolic volume (r = 0.72, p less than 0.001) than to systolic blood pressure (r = 0.46, p less than 0.001); thus, the relatively weak correlation between blood pressure and optimal mass reflected the influence of left ventricular cavity size, rather than a lack of proportionality between load and hypertrophy. Actual and theoretically optimal left ventricular mass were closely related (r = 0.76, p less than 0.001), indicating that left ventricular hypertrophy in most cases paralleled hemodynamic load. Left ventricular mass was positively related to stroke index and inversely to contractility (as estimated by the end-systolic stress/volume index ratio), the main determinants of left ventricular chamber volume. In multivariate analysis, systolic blood pressure, stroke index, and the end-systolic stress/volume index ratio were each independently related to left ventricular mass index (all p less than 0.001, multiple R = 0.81) and accounted for 66% of its overall variability.(ABSTRACT TRUNCATED AT 400 WORDS)
高血压患者收缩压与左心室质量之间的弱关联常被解释为对肌肉生长存在非血液动力学刺激的证据。为了验证这一假说，即反映血液动力学容量负荷和心肌收缩力的左心室腔大小会影响高血压患者左心室肥厚的发展，我们研究了左心室质量与左心室舒张末期腔容积、压力、容量负荷以及收缩力指标之间的实际关系和理论关系。数据来自对50名正常受试者和50名未经治疗的原发性高血压患者独立测量的M型和二维超声心动图。评估了两个总体左心室负荷指标：总负荷（收缩压×左心室内膜表面积）和最大子午线力（收缩压×左心室横截面积）。根据收缩压和M型左心室舒张末期直径计算出理论上的最佳左心室质量，使每个受试者达到平均正常的峰值应力。通过M型超声心动图测量的左心室质量与二维超声心动图得出的左心室舒张末期容积相关性更好（r = 0.56，p < 0.001），而与收缩压的相关性较差（r = 0.45，p < 0.001），与总负荷或最大子午线力的相关性最佳（r = 0.68和0.70，p < 0.001）。在多变量分析中，舒张末期容积和血压都是收缩期质量的独立预测因素（p < 0.001），并解释了其大部分变异性（R = 0.75，p < 0.001）。理论上的最佳左心室质量与舒张末期容积的相关性比与收缩压的相关性更紧密（r = 0.72，p < 0.001）；因此，血压与最佳质量之间相对较弱的相关性反映了左心室腔大小的影响，而非负荷与肥厚之间缺乏比例关系。实际左心室质量与理论上的最佳左心室质量密切相关（r = 0.76，p < 0.001），表明在大多数情况下左心室肥厚与血液动力学负荷平行。左心室质量与每搏输出指数呈正相关，与收缩力呈负相关（通过收缩末期应力/容积指数比值估算），这是左心室腔容积的主要决定因素。在多变量分析中，收缩压、每搏输出指数和收缩末期应力/容积指数比值各自独立与左心室质量指数相关（所有p < 0.001，复相关系数R = 0.81），并占其总体变异性的66%。（摘要截选至400词）
