Acute Cardiovascular Effects of Caffeine: Hemodynamics and Heart Function
Barry D. Smith, Uma Gupta, B.S. Gupta in Caffeine and Activation Theory, 2006
Any increase in arterial stiffness elevates central arterial pressure, with a resulting increase in cardiac workload and myocardial demand. It is therefore not surprising that arterial stiffness is associated with left ventricular hypertrophy, decreased myocardial perfusion, and hypertension (Vlachopoulos, Aznaouridis, & Stefanadis, 2005). Confirming these observations, investigators in the Rotterdam Study assessed CHD risk factors in 2885 subjects. They found that aortic pulse wave velocity, a measure of arterial stiffness, was associated with increased risk for coronary heart disease (CHD) and stroke (Mattace–Raso et al., 2006). The question we raise here is whether or not caffeine consumption increases arterial stiffness or aortic pulse wave reflection. Methods for measurement of these cardiovascular parameters are mixed, and there has been a call for standardization of measurement (Van Bortel et al., 2002). However, results relating to caffeine have been quite consistent (Papaioannou, Karatzis, Papmichael, & Lekakis, 2005).
Heart Rate as a Cardiovascular Risk Factor in Hypertension
Giuseppe Mancia, Guido Grassi, Konstantinos P. Tsioufis, Anna F. Dominiczak, Enrico Agabiti Rosei in Manual of Hypertension of the European Society of Hypertension, 2019
However, several experimental data show that a low heart rate actually improves large artery distensibility. This was shown long ago by the Milan group in both rats and human beings (59). By increasing heart rate with pacing, these authors demonstrated that carotid distensibility as measured from echo Doppler progressively declined with increasing heart rate. Consistent results were obtained in human beings with measurement of pulse wave velocity. Using the same technique to increase heart rate, a French group (60) and an Australian group (61) found a progressive increase in large artery stiffness also when data were adjusted for changes in blood pressure. Recent data from the HARVEST study confirmed the negative relationship between heart rate and the augmentation index in acute studies (unpublished results). However, ambulatory heart rate showed a positive relationship with the augmentation index measured 7 years later.
Hypertension
Henry J. Woodford in Essential Geriatrics, 2022
Hypertension is a major risk factor for cardiovascular disease (CVD). It is associated with an increased risk of stroke, ischaemic heart disease, kidney disease, heart failure and death. Ageing of the vascular system increases arterial stiffness, which raises pulse wave velocity and systolic blood pressure (BP) (see page 10). Hypertension becomes increasingly common as we get older, yet is under-recognised and potentially undertreated. The Framingham Heart Study found the prevalence of hypertension to be 27% in those aged below 60, rising to 63% aged 60–79, and 74% of people aged over 80.1 At that time, only 32% of people with hypertension were on adequate treatment to lower their BP below 140/90 mmHg. However, more recent data suggest that detection and control have increased. Currently in the US, more than 30% of people aged over 80 with hypertension take three or more different antihypertensive medications each day, and 54% of people aged over 80 have a systolic BP < 140 mmHg.2 In addition, 19% have a systolic BP < 120 mmHg, raising the possibility of over-treatment in some people.
Comparison of cuff-based and cuffless continuous blood pressure measurements in children and adolescents
Published in Clinical and Experimental Hypertension, 2020
Jacek Zachwieja, Anna Neyman-Bartkowiak, Alina Rabiega, Marta Wojciechowska, Małgorzata Barabasz, Anna Musielak, Magdalena Silska-Dittmar, Danuta Ostalska-Nowicka
The cuffless, noninvasive Somnotouch-NIBP (Somnomedics GmbH, Randersacker, Germany) system estimates the BP based on the PTT technique, allowing continuous beat-to-beat BP monitoring. Because every single pulse wave is detected, a nonstop “beat-to-beat” recording and analysis is possible. Basic parts of the system are a finger photoplethysmograph, three ECG leads, and a watch-like device with integrated activity monitor. The system measures the transit time of a pulse wave from the corresponding ECG R-wave to the finger photoplethysmography signal. The pulse wave velocity is dependent on is the rigidity of arterial wall. Total blood vessel resistance is influenced by the vessel status, current, and previous disease, and of course, by the blood pressure. To include these factors in the calculation, the blood pressure is measured at least once with a blood pressure cuff, and this value is then calibrated to the simultaneously measured PTT-value. Using this one-point or two-point calibration, and the patient’s height, a precise systolic and diastolic blood pressure value can be calculated for each PTT-value. The principle is based on the assumption that high pulse wave propagation, resulting in shorter PTT, is associated with higher BP and vice versa. Pulse wave propagation and thus PTT depend on arterial wall stiffness and tension, both of which vary according to BP differences (15)
Pulse wave analysis using the Mobil-O-Graph, Arteriograph and Complior device: a comparative study
Published in Blood Pressure, 2019
Dimitrios Benas, Michalis Kornelakis, Helen Triantafyllidi, Gavriela Kostelli, George Pavlidis, Maria Varoudi, Dimitrios Vlastos, Vaia Lambadiari, John Parissis, Ignatios Ikonomidis
Increased arterial stiffness predicts cardiovascular morbidity and mortality [1]. Pulse wave analysis is used to measure pulse wave velocity, the most validated marker of arterial stiffness and central blood pressure. Complior and Arteriograph are validated devices for the measurement of pulse wave velocity (PWV) and central systolic blood pressure (cSBP) [2]. Complior (ALAM, Vincennes France) uses two non-invasive pressure sensors to simultaneously record pulse waves in the carotid and femoral arteries (piezoelectronic method). Arteriograph (TensioMed, Budapest, Hungary), on the other hand, uses an oscillometric method to detect signals from the upper arm cuff for PWV measurement after overinflation. Later-released Mobil-O-Graph (IEM Gmbm, Stolberg, Germany) also uses an oscillometric cuff. The agreement between Mobil-O-Graph and Sphygmocor device in terms of cSBP assessment was found very good [3]. Studies have compared Complior to Arteriograph, showing considerable agreement between these two for the measurement of PWV. However, the comparison of PWV and most importantly central blood pressure values derived from Mobil-O-Graph with the respective values derived by Arteriograph and Complior has not been fully investigated. The aim of our study was to compare PWV and cSBP values by the gold-standard Complior device with Arteriograph (which has been used in our previous studies) and later-released Mobil-O-Graph in the same subjects. We compared the values of PWV and cSBP derived from the 3 devices (Arteriograph, Mobil-O-Graph and Complior) among subjects with several cardiovascular risk factors.
The effect of exercise training interventions in adult kidney transplant recipients: a systematic review and meta-analysis of randomised control trials
Published in Physical Therapy Reviews, 2022
Thomas J. Wilkinson, Nicolette C. Bishop, Roseanne E. Billany, Courtney J. Lightfoot, Ellen M. Castle, Alice C. Smith, Sharlene A. Greenwood
Three studies measured pulse wave velocity (PWV), a marker of arterial stiffness. Due to the heterogeneity of data, a meta-analysis was not possible. Greenwood et al. [31]. found a significant reduction in PWV of 2.2 ± 0.4 m/s (95%CI: −23.1 to 21.3) between the aerobic training and usual care groups, and a significant reduction of 2.6 ± 0.4 m/s (95%CI: −23.4 to 21.7) between the resistance training and usual care groups, at 12-weeks. In a 9-month follow up, O’Connor et al. [37] reported there were no significant within-group changes in PWV in the follow-up period. As such, PWV remained significantly reduced in the resistance training arm vs. the usual care group (−1.30 m/sec, 95%CI: −2.44 to −0.17)). When comparing aerobic and usual care groups at 9-months, the mean difference was −1.05 m/sec (95%CI: −2.11 to 0.017). Tzvetanov et al. [44] found that mean PWV decreased substantially from 9.4 ± 6.3 m/s at baseline to 7.7 ± 1.7 m/s at 12-months in the exercise group (a reduction of 1.7 m/s) (PWV was not measured in the control group). Tzvetanov et al. [44] also measured carotid intima-media thickness and found a non-significant decrease from 0.64 ± 0.2 mm at baseline to 0.60 ± 0 at 12-months in the exercise group. Riess et al. [35]. used arterial pulse waveform analysis to measure artery compliance. They found small artery compliance and large artery compliance were not different between groups.