Cloud Geoffrey C, Rajkumar Chakravarthi, Kooner Jaspal, Cooke Jonathan, Bulpitt Christopher J
Section of Geriatric Medicine, Imperial College School of Medicine, Hammersmith Hospital, DuCane Road, London W12 ONN, UK.
Clin Sci (Lond). 2003 Aug;105(2):219-25. doi: 10.1042/CS20030012.
Central arterial pressure, measured close to the heart, may be of more patho-physiological importance than conventional non-invasive cuff blood pressure. The technique of applanation tonometry using SphygmoCor has been proposed as a non-invasive method of estimating central pressure. This relies on mathematically derived generalized transfer functions, which have been previously validated using invasive peripheral pressure measurements. We compared simultaneous estimates of central aortic pressure using this technique with those measured directly during the routine diagnostic cardiac catheterization of 30 subjects (age range 27-84 years), half of whom were aged 65 years or more. This was done by applanating the left radial artery and recording the non-invasive brachial cuff blood pressure to generate a central aortic pressure estimate, using the SphygmoCor radial transfer function. The comparative results were analysed using Bland-Altman plots of mean difference. SphygmoCor, on average, underestimated systolic central arterial pressure by 13.3 mmHg and overestimated diastolic pressure by 11.5 mmHg. The results were similar in patients aged under and above 65 years. Furthermore, non-invasively measured brachial pressures were seen to give an overall closer estimate of the central arterial pressure than the SphygmoCor system. The transfer function has been validated from invasively measured arterial pressures and the current use by the system of non-invasive measures may explain the discrepancies. However, age, drugs and arterial disease would also be expected to play a role.
在心脏附近测量的中心动脉压可能比传统的无创袖带血压具有更大的病理生理学重要性。已提出使用SphygmoCor的压平眼压测量技术作为估计中心压力的一种无创方法。这依赖于通过数学推导得出的广义传递函数，该函数先前已通过有创外周压力测量得到验证。我们将使用该技术对30名受试者（年龄范围27 - 84岁）进行常规诊断性心脏导管插入术时直接测量的中心主动脉压估计值与同时使用该技术得到的估计值进行了比较，其中一半受试者年龄在65岁及以上。通过压平左桡动脉并记录无创肱动脉袖带血压，使用SphygmoCor桡动脉传递函数来生成中心主动脉压估计值。使用平均差异的Bland - Altman图分析比较结果。平均而言，SphygmoCor低估收缩期中心动脉压13.3 mmHg，高估舒张压11.5 mmHg。65岁以下和65岁以上患者的结果相似。此外，与SphygmoCor系统相比，无创测量的肱动脉压总体上能更接近地估计中心动脉压。传递函数已通过有创测量的动脉压得到验证，该系统目前使用无创测量方法可能解释了这些差异。然而，年龄、药物和动脉疾病预计也会起作用。
