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Pulse pressure is not constant throughout the arterial tree increasing centrifugally. Therefore, use of pulse pressure at one arterial site, such as brachial artery, as surrogate for pulse pressure at another arterial site may be erroneous. Applanation tonometry allows the non invasive determination of arterial pulse pressure in both central and peripheral arteries. However it cannot be applied to all subjects (such as obese) and at all arterial sites. In contrast, B-mode echographic derived arterial diameter waveforms can be obtained at more arterial sites and also in a majority of obese subjects. The aim of this study was to investigate the accuracy of the pulse pressure assessed by calibration of echographic arterial diameter waveforms. The left common carotid artery of 49 normotensive subjects (NT) and 45 hypertensive (HT) patients were measured non invasively by using tonometry and automatic analysis of B-mode echographic images, to obtain instantaneous pressure (P) and diameter (D) signals. Calibration of carotid D and P was assessed from tonometer brachial artery waves and sphygmomanometer, assuming mean minus diastolic pressure constant throughout the arterial tree. Pulse pressure from calibrated diameter waves was 4±2 mmHg (NT vs. HT not significant) lower than pulse pressure from tonometer calibrated pressure waves (used as reference method), with a correlation coefficient of r=0.99 (p<0.05). In conclusion, pulse pressure obtained from alternatively calibrated B-mode derived arterial diameter waveforms demonstrates good accuracy within the acceptability limits of the AAMI criteria. [ABSTRACT FROM AUTHOR]

The left ventricle (LV) torsion is an important feature of the ventricle's biomechanics. Using speckle-tracking echography (STE) the assessment of LV torsion dynamics would be more available in clinical and research cardiology Particular features of the LV torsion have been described during exercise and in some sportsmen, but up to now the LV torsion dynamics has not been studied in soccer players. The aims were to characterize the LV systolic and diastolic torsion dynamic in professional soccer players using STE, and to analyze the main differences in torsion dynamics between soccer players and age-matched non-trained individuals. To this end the LV apical and basal rotation were quantified, and the systolic and diastolic torsion dynamic was characterized using a time and frequency-domain approach. The STE allowed characterizing the LV torsion level in both groups. The LV torsion level was lesser in soccer players than in non-trained individuals. Soccer players showed lesser amplitudes in the low frequency components of the LV torsion Fourier spectrum. [ABSTRACT FROM AUTHOR]

Several factors have been implicated in the circadian pattern of cardiovascular vulnerability. However, the exact mechanisms involved in the peak incidence of cardiovascular events occurring during the early morning hours and in the afternoon are not completely identified. Arterial stiffness (AS) is a risk factor for cardiovascular morbidity and mortality. The purpose of our study was to investigate the circadian variation of AS in healthy individuals and to test the hypothesis that there was a circadian pattern in the AS coincident with the circadian variation in the cardiovascular susceptibility. Additionally, a night-daytime comparison of AS was performed. Method: 24-hrs of ambulatory blood pressure, heart rate and aortic-brachial pulse transit time (PTTAB) recordings were obtained in sixteen healthy individuals. AS surrogates, derived from the PTTAB and systolic and diastolic pressure were calculated. The myocardial oxygen consumption (MVO2) was quantified. The AS and MVO2 shows a circadian pattern with the highest and lowest levels, respectively, in the night. The greater reductions in the AS were temporally coincident with the morning increase in the arterial pressure, heart rate, and MVO2. The lesser AS found during the day-time, could be considered a physiological adaptation to minimize the oxygen consumption during the period of maximal physical activity. [ABSTRACT FROM AUTHOR]