The (dP/dt)max derived from arterial pulse waveforms during 24 h blood pressure oscillometric recording

BACKGROUND: The modern developments in engineering allow one to record the speed at which the blood pressure rises on the advancing pulse wave front. It was possible to obtain this through the conversion of a conventional pulse from a single suprasystolic oscillation to the oscillometric envelope into its first derivative with respect to time. OBJECTIVE: The aim of this study was to report a preliminary comparison between healthy subjects and patients with heart failure as a first step towards the clinical ujse of this first derivative of a time-dependent function (dP/dt).METHODS: For 10 normal healthy subjects (aged 37 +/- 5 yhears) and five subjects with ischaemic cardiomyopathy (aged 41 +/- 7 years), whose ejection fractions (invasively assessed) wee < 40%, we evaluated six sequential oscillometric measurements of blood pressure obtain by using a Dynapulse Ps5000 (Pulse Metric, San Diego, California, USA) device, which simultaneously records blood pressure and analyses every arterial waveform. The mean and SD of (dP/dt)max for each subject were calculated, together with the relative mean distribution and the significance of the differences. RESULTS: The data show that (dP/dt)max of subjects with an impairment of cardiac function is less than normal. The mean (dP/dt)max of normalk subjects was significantly different (P < 0.05) from that of patients with ischaemic cardiomyopathy and lower than normalk ejection fractions. CONCLUSION: These preliminary results allowed us to raise the hypothesis that this parameter, being representative of the cardiac function, because many data are obtained, is extremely useful for monitoring changes during daily activities or to outline the nycthoemeral rhythm. We have to test the hypotheses that the analyses of the correlations between (dP/dt)max and other haemodynamic parameters may be used in the pathphysiological study of cardiomyopathies and that the comparison of differences in (dP/dt)max can be used in the evaluation of the effects of the treatment.