Narayan Om, Davies Justin E, Hughes Alun D, Dart Anthony M, Parker Kim H, Reid Christopher, Cameron James D
From the Monash Cardiovascular Research Centre, School of Clinical Sciences at Monash, Monash University, Melbourne Australia (O.N., J.D.C.); International Centre for Circulatory Health (J.E.D.), and Department of Bioengineering (K.H.P.), Imperial College, London, United Kingdom; UCL Institute of Cardiovascular Science, University College London, United Kingdom (A.D.H.); Baker IDI Heart and Diabetes Institute, Melbourne, Australia (A.M.D.); Department of Epidemiology & Preventative Medicine, Monash University, Melbourne, Australia (C.R.); and MonashHeart, Monash Health, Victoria, Australia (O.N., J.D.C.).
Hypertension. 2015 Mar;65(3):629-35. doi: 10.1161/HYPERTENSIONAHA.114.04824. Epub 2014 Dec 22.
Several morphological parameters based on the central aortic pressure waveform are proposed as cardiovascular risk markers, yet no study has definitively demonstrated the incremental value of any waveform parameter in addition to currently accepted biomarkers in elderly, hypertensive patients. The reservoir-wave concept combines elements of wave transmission and Windkessel models of arterial pressure generation, defining an excess pressure superimposed on a background reservoir pressure. The utility of pressure rate constants derived from reservoir-wave analysis in prediction of cardiovascular events is unknown. Carotid blood pressure waveforms were measured prerandomization in a subset of 838 patients in the Second Australian National Blood Pressure Study. Reservoir-wave analysis was performed and indices of arterial function, including the systolic and diastolic rate constants, were derived. Survival analysis was performed to determine the association between reservoir-wave parameters and cardiovascular events. The incremental utility of reservoir-wave parameters in addition to the Framingham Risk Score was assessed. Baseline values of the systolic rate constant were independently predictive of clinical outcome (hazard ratio, 0.33; 95% confidence interval, 0.13-0.82; P=0.016 for fatal and nonfatal stroke and myocardial infarction and hazard ratio, 0.38; 95% confidence interval, 0.20-0.74; P=0.004 for the composite end point, including all cardiovascular events). Addition of this parameter to the Framingham Risk Score was associated with an improvement in predictive accuracy for cardiovascular events as assessed by the integrated discrimination improvement and net reclassification improvement indices. This analysis demonstrates that baseline values of the systolic rate constant predict clinical outcomes in elderly patients with hypertension and incrementally improve prognostication of cardiovascular events.
基于中心主动脉压力波形的几个形态学参数被提议作为心血管风险标志物，但尚无研究明确证明在老年高血压患者中，除了目前已被认可的生物标志物外，任何波形参数的增量价值。弹性贮器波概念结合了动脉压力产生的波传播模型和Windkessel模型的要素，定义了叠加在背景贮器压力上的过剩压力。从弹性贮器波分析得出的压力速率常数在预测心血管事件中的效用尚不清楚。在第二次澳大利亚全国血压研究中，对838例患者的一个子集在随机分组前测量了颈动脉血压波形。进行了弹性贮器波分析，并得出了包括收缩期和舒张期速率常数在内的动脉功能指标。进行生存分析以确定弹性贮器波参数与心血管事件之间的关联。评估了除弗明汉姆风险评分外弹性贮器波参数的增量效用。收缩期速率常数的基线值可独立预测临床结局（风险比为0.33；95%置信区间为0.13 - 0.82；致命和非致命性卒中和心肌梗死的P = 0.016，包括所有心血管事件的复合终点的风险比为0.38；95%置信区间为0.20 - 0.74；P = 0.004）。将该参数添加到弗明汉姆风险评分中，根据综合判别改善和净重新分类改善指数评估，与心血管事件预测准确性的提高相关。该分析表明，收缩期速率常数的基线值可预测老年高血压患者的临床结局，并逐步改善心血管事件的预后。
