St Goar F G, Masuyama T, Alderman E L, Popp R L
Division of Cardiology, Stanford University School of Medicine, CA 94305.
J Am Soc Echocardiogr. 1991 Jul-Aug;4(4):349-60. doi: 10.1016/s0894-7317(14)80445-8.
Left ventricular diastolic dysfunction is an integral component of end-stage dilated cardiomyopathy. To better characterize this disorder we studied 15 patients undergoing catheterization during cardiac transplant screening evaluation. Pulsed-wave Doppler echocardiographic recordings of mitral inflow were obtained with simultaneous high-fidelity left ventricular and phase-corrected pulmonary capillary wedge pressures. Doppler-derived isovolumic relaxation times were within normal limits, despite a prolonged coefficient of relaxation (tau), and correlated with pulmonary capillary wedge--left ventricular crossover pressure. Peak velocity of early diastolic filling was similar to that reported in normal subjects and did not correlate with crossover pressure or tau. Early diastolic acceleration and deceleration times were shortened compared with reported normal values. Acceleration time correlated with mean negative dP/dt from mitral valve opening to left ventricular minimum pressure and with crossover pressure, and deceleration time correlated with mean dP/dt from left ventricular minimum pressure to the peak of the rapid filling wave. Late diastolic filling at atrial contraction was absent in 12 patients, all of whom had a significant early diastolic rapid filling wave and an elevated end-diastolic pressure. Despite an increase in pulmonary capillary wedge pressure during atrial contraction, the failing ventricles were unable to generate detectable forward transmitral flow. Poor cardiac pump function was shown by low left ventricular stroke volume, which correlated with the diastolic flow velocity integral. Thus, in end-stage cardiomyopathy, the transmitral flow velocity pattern is characterized by normal peak early filling velocity, low normal isovolumic relaxation time, shortened acceleration and deceleration times of early diastolic flow, decreased early flow velocity integral, and absent or decreased filling during atrial contraction. This pattern reflects interaction between elevated transmitral driving pressure and the compromised relaxation and compliance of a left ventricle functioning on an elevated pressure-volume curve.
左心室舒张功能障碍是终末期扩张型心肌病的一个重要组成部分。为了更好地描述这种疾病，我们研究了15例在心脏移植筛查评估期间接受心导管检查的患者。在同步记录高保真左心室压力和相位校正的肺毛细血管楔压的情况下，获得二尖瓣血流的脉冲波多普勒超声心动图记录。尽管舒张系数（tau）延长，但多普勒衍生的等容舒张时间仍在正常范围内，且与肺毛细血管楔压-左心室交叉压相关。舒张早期充盈峰值速度与正常受试者报道的相似，且与交叉压或tau无关。与报道的正常值相比，舒张早期加速和减速时间缩短。加速时间与二尖瓣开放至左心室最小压力的平均负dP/dt以及交叉压相关，减速时间与左心室最小压力至快速充盈波峰值的平均dP/dt相关。12例患者心房收缩期无舒张晚期充盈，所有这些患者均有明显的舒张早期快速充盈波和舒张末期压力升高。尽管心房收缩期肺毛细血管楔压升高，但衰竭的心室无法产生可检测到的前向二尖瓣血流。左心室每搏量低表明心脏泵功能差，这与舒张期血流速度积分相关。因此，在终末期心肌病中，二尖瓣血流速度模式的特征为舒张早期充盈峰值速度正常、等容舒张时间正常偏低、舒张早期血流加速和减速时间缩短、舒张早期血流速度积分降低以及心房收缩期充盈缺失或减少。这种模式反映了升高的二尖瓣驱动压力与在升高的压力-容积曲线上功能的左心室舒张和顺应性受损之间的相互作用。
