Department of Cardiology, Leiden University Medical Centre, PO Box 9600, 2300RC, Leiden, The Netherlands.
Heart. 2010 Feb;96(3):213-9. doi: 10.1136/hrt.2009.176248. Epub 2009 Oct 28.
To test a method to predict the end-diastolic pressure-volume relationship (EDPVR) from a single beat in patients with heart failure.
Patients (New York Heart Association class III-IV) scheduled for mitral annuloplasty (n=9) or ventricular restoration (n=10) and patients with normal left ventricular function undergoing coronary artery bypass grafting (n=12) were instrumented with pressure-conductance catheters to measure pressure-volume loops before and after surgery. Data obtained during vena cava occlusion provided directly measured EDPVRs. Baseline end-diastolic pressure (P(m)) and volume (V(m)) were used for single-beat prediction of EDPVRs. Root-mean-squared error (RMSE) between measured and predicted EDPVRs, was 2.79+/-0.21 mm Hg. Measured versus predicted end-diastolic volumes at pressure levels 5, 10, 15 and 20 mm Hg showed tight correlations (R(2)=0.69-0.97). Bland-Altman analyses indicated overestimation at 5 mm Hg (bias: pre-surgery 44 ml (95% CI 29 to 58 ml); post-surgery 35 ml (23 to 47 ml)) and underestimation at 20 mm Hg (bias: pre-surgery -57 ml (-80 to -34 ml); post-surgery -13 ml (-20 to -7.0 ml)). End-diastolic volumes were significantly different between groups and between conditions, but these differences were not dependent on the method (ie, measured versus predicted). RMSEs were not different between groups or conditions, nor dependent on V(m) or P(m), indicating that EDPVR prediction was equally accurate over a wide volume range.
Single-beat EDPVRs obtained from hearts spanning a wide range of sizes and conditions accurately predicted directly measured EDPVRs with low RMSE. Single-beat EDPVR indices correlated well with directly measured values, but systematic biases were present at low and high pressures. The single-beat method facilitates less invasive EDPVR estimation, particularly when coupled with emerging non-invasive techniques to measure pressures and volumes.
测试一种从心力衰竭患者单次心跳中预测舒张末期压力-容积关系（EDPVR）的方法。
接受二尖瓣环成形术（n=9）或心室修复术（n=10）的患者以及接受冠状动脉旁路移植术（n=12）的左心室功能正常的患者均接受压力-传导导管置管术，以在术前和术后测量压力-容积环。腔静脉闭塞期间获得的数据提供了直接测量的 EDPVR。基线舒张末期压力（P（m））和容积（V（m））用于单次心跳预测 EDPVR。测量和预测 EDPVR 之间的均方根误差（RMSE）为 2.79+/-0.21mmHg。在压力水平 5、10、15 和 20mmHg 时，测量与预测的舒张末期容积之间存在紧密相关性（R（2）=0.69-0.97）。Bland-Altman 分析表明在 5mmHg 时存在高估（偏差：术前 44ml（95%CI 29 至 58ml）；术后 35ml（23 至 47ml）），在 20mmHg 时存在低估（偏差：术前 -57ml（-80 至 -34ml）；术后 -13ml（-20 至 -7.0ml））。各组之间以及各组内的舒张末期容积存在显著差异，但这些差异不依赖于方法（即，测量值与预测值）。RMSE 在各组或条件之间没有差异，也不依赖于 V（m）或 P（m），这表明 EDPVR 预测在广泛的容积范围内同样准确。
从大小和条件范围广泛的心脏中获得的单次心跳 EDPVR 能够准确预测直接测量的 EDPVR，具有较低的 RMSE。单次心跳 EDPVR 指数与直接测量值相关性良好，但在低压力和高压力下存在系统偏差。单次心跳法有利于更具侵入性的 EDPVR 估计，特别是当与新兴的非侵入性技术相结合以测量压力和容积时。
