Late Systolic Pressure Research Articles

Abstract Mo105: End Systolic Pressure and Ejection Timing Correlate with Impaired Relaxation

Impaired relaxation is a common feature in most cases of diastolic dysfunction, including heart failure with preserved ejection fraction. Isovolumetric relaxation is typically characterized by τ, an exponential time constant, but may be broken into relaxation and stiffness-like parameters (µ and Ek). Recent in vitro work suggests that strain during late systole (protodiastolic period) modifies relaxation. We hypothesize that late systolic pressure and time indexes correlate with myocardial relaxation. Thirty-four (34) simultaneous aortic and left ventricular micromanometric (Millar) pressure traces were obtained from a comprehensive database of clinical cardiac catheterization patients. These patients underwent coronary artery disease screening and presented but did not have arterial blockages. Pressure and time parameters were calculated over a five-minute interval. Relaxation rate (1/τ), and stiffness (Ek) correlated to end systolic parameters in an orthogonal pattern to relaxation (µ). 1/τ showed strong correlations with time from peak pressure to aortic valve divided by ejection time (t54/t52, r = .675, p < .01) and moderate correlation to the pressure decline after peak pressure to aortic valve pressure divided by the pulse pressure (P45/P42, r = .577, p < .01). In parallel Ek showed moderate correlation with t54/t52 (r = .592, p < .01), and a moderate correlation with P45/P42 (r = .470, p < .01), the pressure at aortic valve closure (r = -.420, p < .05), and aortic augmentation index (AIx, r = -.360, p < .05). Finally, µ presented a moderate correlation to P45/P42 (r = .501, p < .05), the pressure at aortic valve closure (r = .404, p < .05), and AIx (r = -.357, p < .05). As predicted, ventricular relaxation in patients correlates with late systolic hemodynamics. Parameters or combinations of parameters may predict relaxation rates or correlate to in vivo late systolic strain. Prospective studies evaluating end systolic strain and relaxation merit consideration. Overall, these observations are consistent with in vitro studies that suggest that impaired cessation of contraction is a regulator of relaxation.

The effect of isometric exercise training on arterial stiffness: A randomized crossover controlled study.

Isometric exercise training (IET) is an effective intervention for the management of resting blood pressure (BP). However, the effects of IET on arterial stiffness remain largely unknown. Eighteen unmedicated physically inactive participants were recruited. Participants were randomly allocated in a cross-over design to 4 weeks of home-based wall squat IET and control period, separated by a 3-week washout period. Continuous beat-to-beat hemodynamics, including early and late systolic (sBP 1 and sBP 2, respectively) and diastolic blood pressure (dBP) were recorded for a period of 5 min and waveforms were extracted and analyzed to acquire the augmentation index (AIx) as a measure of arterial stiffness. sBP 1 (-7.7 ± 12.8 mmHg, p = 0.024), sBP 2 (-5.9 ± 9.9 mmHg, p = 0.042) and dBP (-4.4 ± 7.2 mmHg, p = 0.037) all significantly decreased following IET compared to the control period. Importantly, there was a significant reduction in AIx following IET (-6.6 ± 14.5%, p = 0.02) compared to the control period. There were also adjacent significant reductions in total peripheral resistance (-140.7 ± 65.8 dynes·cm-5, p = 0.042) and pulse pressure (-3.8 ± 4.2, p = 0.003) compared to the control period. This study demonstrates an improvement in arterial stiffness following a short-term IET intervention. These findings have important clinical implications regarding cardiovascular risk. Mechanistically, these results suggest that reductions in resting BP following IET are induced via favorable vascular adaptations, although the intricate details of such adaptations are not yet clear.

Toll-like receptor 4 activation contributes to systemic vascular dysfunction in pregnant rats fed a high cholesterol diet during pregnancy

Background: Hypercholesterolemia is a hallmark clinical feature of cardiovascular diseases. Vascular adaptations to pregnancy include withstanding pregnancy-induced hypercholesterolemia, a physiological process required for fetus development. However, excessive (pathological) hypercholesterolemia during pregnancy has been linked to an increased risk of complications (e.g., preeclampsia); still, the underlying mechanisms are unclear. Toll-like receptor 4 (TLR4) is an innate immune receptor modulated by high cholesterol levels (in non-pregnant animals), but whether TLR4 activation also plays a role in vascular dysfunction in pregnancies complicated with hypercholesterolemia is unknown. Hypothesis: Pathological hypercholesterolemia during pregnancy causes maternal vascular dysfunction via activation of TLR4. Methods: Sprague Dawley rats were fed a standard (CD) or high cholesterol diet (HCD; 2% cholesterol and 0.5% cholic acid) from gestational day (GD) 6 to GD20 (term=22 days; n=9-10). Blood pressure was assessed before pregnancy and on GD19, and the results are presented as delta change. On GD20, body weight and pregnancy outcomes were recorded, and mesenteric arteries (systemic resistance arteries) were assessed using wire myography to evaluate vasoconstriction capacity to phenylephrine and endothelial-dependent vasodilation responses to methacholine. Experiments were conducted in the presence or absence of L-NAME (a pan-NOS inhibitor, 100 mmol/l) and/or CLI-095 (a TLR4 inhibitor, 10 mmol/l). Functional data were summarized as Emax (maximum response) or pEC50 (concentration required to produce 50% of Emax). Statistics: Student’s t-test or two-way ANOVA with Sidak post hoc test (significance: p<0.05). Results: The HCD prevented the late gestation systolic (p=0.0004) and diastolic (p=0.0066) blood pressure reduction observed in the CD group, and impaired male (p=0.0062) and female (p=0.0352) fetoplacental efficiency. Total body weight gain during pregnancy was not different between CD and HCD dams (p>0.05). In mesenteric arteries, vasoconstriction responses to phenylephrine (Emax) were increased in HCD dams (p=0.0056), and TLR4 inhibition with CLI-095 reduced the sensitivity (pEC50) of phenylephrine in these vessels (p=0.0147). Additionally, HCD dams presented higher sensitivity (pEC50) to methacholine (p=0.0169), which was not modified by the TLR4 inhibitor (p>0.05). Incubation of arteries with L-NAME abolished the increased sensitivity to methacholine (p>0.05), which was not further altered by CLI-095 (p>0.05). Conclusion: Inhibition of TLR4 ( ex vivo) reduced the enhanced vasoconstriction observed in HCD dams but did not alter endothelial-dependent vasodilation responses. Thus, if inhibiting TLR4 could block the vasoconstrictor effects of excessive hypercholesterolemia during pregnancy, this may be a target for future therapy development. This work was supported by a foundation grant from CIHR (FS154313) and by the generosity of the Stollery Children's Hospital Foundation and the Alberta Women's Health Foundation through the Women and Children's Health Research Institute (WCHRI). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Advancing High-Resolution Imaging of Scalp EEG and Mobile Brain/Body Imaging

Radial augmentation index (rAI), a marker of aortic wave reflection, is usually lower in patients with diabetes (DM) than in non-DM subjects, even though atherosclerotic change is advanced in DM.We sought to explore why rAI in DM is lower than in non-DM.We performed radial applanation tonometry in 1787 subjects who had at least one cardiovascular risk factor. The rAI was defined as [late systolic shoulder pressure amplitude (PP2)]/[radial pulse pressure (rPP)]. The late systolic shoulder blood pressure (SBP2) and PP2 of a radial pressure wave were used as estimates of the central SBP and PP (cPP), respectively.The age (65.8 ± 9.8 vs. 65.8 ± 12.1 yrs) and mean brachial SBP (141 ± 16 vs. 141 ± 17 mmHg) were similar between the DM and non-DM groups. The rAI was significantly lower in the DM group (83.3 ± 14.1 vs. 87.3 ± 15.7%, p < 0.001), but clinic PP (62 ± 14 vs. 59 ± 14 mmHg, p < 0.001) and cPP (51 ± 15 vs. 49 ± 15 mmHg, p = 0.019) were significantly greater in the DM group than in the non-DM group. In multivariable analyses adjusting for covariates, the significant determinants of rAI were the estimated glomerular filtration rate (eGFR) (β = 0.17, p < 0.001) in the DM group, and the log-transformed homeostatic model assessment of insulin resistance (HOMA-IR) (β = −0.15, p < 0.001) in the non-DM group. The same trends were also seen for central SBP and cPP.The lower rAI in DM associated with higher cPP compared to non-DM suggests proximal conduit–predominant arterial stiffening causing reduced reflection coefficients at systemic reflection sites. As renal function decreases, a cPP increase may overcome the increase of augmentation pressure in the DM group.

Features and implications of higher systolic central than peripheral blood pressure in patients at very high risk of atherosclerotic cardiovascular disease.

Peripheral blood pressure (PBP) is usually higher than central blood pressure (CBP) due to pulse amplification; however, it is not well understood why cuff-measured PBP can be lower than CBP estimated by the late systolic pressure of radial pulse waves. We explored the implications of systolic PBP-CBP (P-CBP) differences for cardiovascular (CV) prognosis. In total, 335 patients at very high risk of atherosclerotic cardiovascular disease (ASCVD) underwent automated applanation tonometry and brachial-ankle pulse wave velocity (baPWV), and they were classified into groups according to positive or negative systolic P-CBP differences. Between-group characteristics and clinical outcomes (the composite of coronary revascularization, stroke, heart failure hospitalization, and CV death) were evaluated. Patients with negative differences had significantly higher frequency of hypertension, coronary artery disease, higher ASCVD risk burden, and elevated N-terminal pro b-type natriuretic peptide. They had higher left atrial volume index (LAVI) and lower systolic mitral septal tissue velocity (TVI-s') than those with a positive difference. These patients showed higher systolic PBP and CBP, and a higher baPWV. Multivariable analysis indicated that TVI-s', LAVI, and ASCVD risk burden were independent determinants of such systolic P-CBP differences. During a median follow-up of 12.6 months, clinical outcomes were significantly related to a negative difference (11.5% vs. 3.4%, p = 0.014), and a systolic P-CBP difference ≤ -8 mmHg was associated with a threefold higher likelihood of poor prognosis. In patients at very high risk of ASCVD, systolic P-CBP difference was associated with cardiac dysfunction and ASCVD risk burden, allowing further risk stratification.

Associations of DASH Diet in Pregnancy With Blood Pressure Patterns, Placental Hemodynamics, and Gestational Hypertensive Disorders.

BackgroundThe Dietary Approaches to Stop Hypertension (DASH) diet improves blood pressure in nonpregnant populations. We hypothesized that adherence to the DASH diet during pregnancy improves hemodynamic adaptations, leading to a lower risk of gestational hypertensive disorders.Methods and ResultsWe examined whether the DASH diet score was associated with blood pressure, placental hemodynamics, and gestational hypertensive disorders in a population‐based cohort study among 3414 Dutch women. We assessed DASH score using food‐frequency questionnaires. We measured blood pressure in early‐, mid‐, and late pregnancy (medians, 95% range: 12.9 [9.8–17.9], 20.4 [16.6–23.2], 30.2 [28.6–32.6] weeks gestation, respectively), and placental hemodynamics in mid‐ and late pregnancy (medians, 95% range: 20.5 [18.7–23.1], 30.4 [28.5–32.8] weeks gestation, respectively). Information on gestational hypertensive disorders was obtained from medical records. Lower DASH score quartiles were associated with a higher mid pregnancy diastolic blood pressure, compared with the highest quartile (P<0.05). No associations were present for early‐ and late pregnancy diastolic blood pressure and systolic blood pressure throughout pregnancy. Compared with the highest DASH score quartile, the lower DASH score quartiles were associated with a higher mid‐ and late pregnancy umbilical artery pulsatility index (P≤0.05) but not with uterine artery resistance index. No associations with gestational hypertensive disorders were present.ConclusionsA higher DASH diet score is associated with lower mid pregnancy diastolic blood pressure and mid‐ and late pregnancy fetoplacental vascular function but not with uteroplacental vascular function or gestational hypertensive disorders within a low‐risk population. Further studies need to assess whether the effects of the DASH diet on gestational hemodynamic adaptations are more pronounced among higher‐risk populations.

Association Between Post-Transplant Visit-to-Visit Pulse Pressure Variability and Late Transplant Systolic Blood Pressure in Non-Elderly Kidney Transplant Recipients

Association Between Post-Transplant Visit-to-Visit Pulse Pressure Variability and Late Transplant Systolic Blood Pressure in Non-Elderly Kidney Transplant Recipients

P1674High intensity interval exercise program in heart failure patients seems to benefit cardiac power along with aorto-ventricular mechanical pump capacity and cardiorespiratory indices

Abstract Background Cardiac power has been suggested as the most power predictor of mortality in heart failure (HF) patients. In those patients aorta elastic properties and compensation is lost, systolic (and pulse) pressure are therefore reduced and associated with a decrease in ejection duration and pump efficiency. Cardiac rehabilitation programs have showed enhancement in cardiac performance and quality of life in HF patients. Aim Aim of this work was to evaluate the effect of high-intensity interval exercise (i.e., 30 sec at 100% of max workload, followed by 30 sec at rest, on a day-by-day 30 minutes working-out schedule for 12 weeks), on cardiac power, diastolic function indices, right ventricle performance and cardiorespiratory parameters among chronic HF patients. Methods 72 consecutive HF patients (NYHA class II-IV, ejection fraction &lt;50%) who completed the study (exercise training group, n=33, 63±9 years, 88% men, and control group, n=39, 56±11 years, 82% men), underwent cardiopulmonary stress test, non-invasive high-fidelity tonometry of the radial artery, pulse wave velocity measurement using a SphygmoCor device, and echocardiography before and after completion of the training program. Cardiac power output (CPO) (W) was calculated as mean arterial pressure × CO/451, where mean arterial pressure = [(systolic blood pressure − diastolic blood pressure)/3] + diastolic blood pressure. Results Both groups reported similar medical characteristics and physical activity status. General mixed effects models revealed that the intervention group increased 6MWT (by 13%, p&lt;0.05); increased cycle ergometry WRpeak (by 25%, p&lt;0.01), showed higher O2max by 31% (p&lt;0.001) and lower VE/VCO2 (p=0.05), whereas patients in the control group showed nosignificant changes in the aforementioned indices. Also, in the intervention group Emv/Vp was decreased by 14% (p=0.06); E to A ratio by 24% (p=0.004) and E to Emv ratio by 8% (p=0.05); while Stv increased by 25% (p=0.01). Most importantly, the intervention group reduced pulse wave velocity by 9% (p=0.05) and increased augmentation index by 26%; and VTI by 4% (p=0.05); Those parameters were not significantly changed on control group (all p&gt;0.05). Conclusion Hight intensity exercise rehabilitation program revealed beneficial effect on left ventricular diastolic indices and right ventricle performance. As, in those patients compensation of the aorta is also lost and the LV cannot generate the extra force necessary to completely overcome the late systolic augmented pressure, the increase in the augmented pressure (AIa) observed in the intervention group reflects the benefit in aorto-ventricular coupling and cardiac power that boosts systolic pressure and restores a positive influence in pressure, like in early stages of HF. Acknowledgement/Funding None

A New Blood Pulsation Simulator Platform Incorporating Cardiovascular Physiology for Evaluating Radial Pulse Waveform.

To meet the need for “standard” testing system for wearable blood pressure sensors, this study intends to develop a new radial pulsation simulator that can generate age-dependent reference radial artery pressure waveforms reflecting the physiological characteristics of human cardiovascular system. To closely duplicate a human cardiovascular system, the proposed simulator consists of a left ventricle simulation module, an aorta simulation module, a peripheral resistance simulation module, and a positive/negative pressure control reservoir module. Simulating physiologies of blood pressure, the compliance chamber in the simulator can control arterial stiffness to produce age-dependent pressure waveforms. The augmentation index was used to assess the pressure waveforms generated by the simulator. The test results show that the simulator can generate and control radial pressure waveforms similar to human pulse signals consisting of early systolic pressure, late systolic pressure, and dicrotic notch. Furthermore, the simulator's left ventricular pressure-volume loop results demonstrate that the simulator exhibits mechanical characteristics of the human cardiovascular system. The proposed device can be effectively used as a “standard” radial artery pressure simulator to calibrate the wearable sensor's measurement characteristics and to develop more advanced sensors. The simulator is intended to serve as a platform for the development, performance verification, and calibration of wearable blood pressure sensors. It will contribute to the advancement of the wearable blood pressure sensor technology, which enables real-time monitoring of users' radial artery pressure waveforms and eventually predicting cardiovascular diseases.

Analysis of aortic pressure fields from 4D flow MRI in healthy volunteers: Associations with age and left ventricular remodeling.

Aging-related arterial stiffness is associated with substantial changes in global and local arterial pressures. The subsequent early return of reflected pressure waves leads to an elevated left ventricular (LV) afterload and ultimately to a deleterious concentric LV remodeling. To compute aortic time-resolved pressure fields of healthy subjects from 4D flow MRI and to define relevant pressure-based markers while investigating their relationship with age, LV remodeling, as well as tonometric augmentation index (AIx) and pulse wave velocity (PWV). Retrospective. Forty-seven healthy subjects (age: 49.5 ± 18 years, 24 women). 3 T/4D flow MRI. Spatiotemporal pressure fields were computed by integrating velocity-derived pressure gradients using Navier-Stokes equations, while assuming zero pressure at the sino-tubular junction. To quantify aortic pressure spatiotemporal variations, we defined the following markers: 1) volumetric aortic pressure propagation rates ΔP E1 /ΔV and ΔP E2 /ΔV, representing variations of early and late systolic relative pressure peaks along the aorta, respectively, according to the cumulated aortic volume; 2) ΔA PE1-PE2 defined in four aortic regions as the absolute difference between early and late systolic relative pressure peaks amplitude. Linear regression, Wilcoxon rank sum test, Bland-Altman analysis, and intraclass correlation coefficients (ICC). Spatiotemporal variations of aortic pressure peaks were moderately to highly reproducible (ICC ≥0.50) and decreased significantly with age, in terms of absolute magnitude: ΔP E1 /ΔV (r = 0.70, P < 0.005), ΔP E2 /ΔV (r = -0.45, P < 0.005) and ΔA PE1-PE2 (|r| > 0.39, P < 0.005). ΔP E1 /ΔV was associated with LV remodeling (r = 0.53, P < 0.001) and ascending aorta ΔA PE1-PE2 was associated with AIx (r = -0.59, P < 0.001). Both associations were independent of age and systolic blood pressures. Only weak associations were found between pressure indices and PWV (r ≤ 0.40). 4D flow MRI relative aortic pressures were consistent with physiological knowledge as demonstrated by their significant volumetric and temporal variations with age and their independent association with LV remodeling and augmentation index. Level of Evidence 2 Technical Efficacy Stage 3 J. Magn. Reson. Imaging 2019;50:982-993.

Exercise Training and Weight Gain in Obese Pregnant Women: A Randomized Controlled Trial (ETIP Trial).

BackgroundThe effectiveness of exercise training for preventing excessive gestational weight gain (GWG) and gestational diabetes mellitus (GDM) is still uncertain. As maternal obesity is associated with both GWG and GDM, there is a special need to assess whether prenatal exercise training programs provided to obese women reduce the risk of adverse pregnancy outcomes. Our primary aim was to assess whether regular supervised exercise training in pregnancy could reduce GWG in women with prepregnancy overweight/obesity. Secondary aims were to examine the effects of exercise in pregnancy on 30 outcomes including GDM incidence, blood pressure, blood measurements, skinfold thickness, and body composition.Methods and FindingsThis was a single-center study where we randomized (1:1) 91 pregnant women with a prepregnancy body mass index (BMI) ≥ 28 kg/m2 to exercise training (n = 46) or control (standard maternity care) (n = 45). Assessments were done at baseline (pregnancy week 12–18) and in late pregnancy (week 34–37), as well as at delivery. The exercise group was offered thrice weekly supervised sessions of 35 min of moderate intensity endurance exercise and 25 min of strength training. Seventeen women were lost to follow-up (eight in the exercise group and nine in the control group). Our primary endpoint was GWG from baseline testing to delivery. The principal analyses were done as intention-to-treat analyses, with supplementary per protocol analyses where we assessed outcomes in the women who adhered to the exercise program (n = 19) compared to the control group. Mean GWG from baseline to delivery was 10.5 kg in the exercise group and 9.2 kg in the control group, with a mean difference of 0.92 kg (95% CI −1.35, 3.18; p = 0.43). Among the 30 secondary outcomes in late pregnancy, an apparent reduction was recorded in the incidence of GDM (2009 WHO definition) in the exercise group (2 cases; 6.1%) compared to the control group (9 cases; 27.3%), with an odds ratio of 0.1 (95% CI 0.02, 0.95; p = 0.04). Systolic blood pressure was significantly lower in the exercise group (mean 120.4 mm Hg) compared to the control group (mean 128.1 mm Hg), with a mean difference of −7.73 mm Hg (95% CI −13.23, −2.22; p = 0.006). No significant between-group differences were seen in diastolic blood pressure, blood measurements, skinfold thickness, or body composition in late pregnancy. In per protocol analyses, late pregnancy systolic blood pressure was 115.7 (95% CI 110.0, 121.5) mm Hg in the exercise group (significant between-group difference, p = 0.001), and diastolic blood pressure was 75.1 (95% CI 71.6, 78.7) mm Hg (significant between-group difference, p = 0.02). We had planned to recruit 150 women into the trial; hence, under-recruitment represents a major limitation of our results. Another limitation to our study was the low adherence to the exercise program, with only 50% of the women included in the intention-to-treat analysis adhering as described in the study protocol.ConclusionsIn this trial we did not observe a reduction in GWG among overweight/obese women who received a supervised exercise training program during their pregnancy. The incidence of GDM in late pregnancy seemed to be lower in the women randomized to exercise training than in the women receiving standard maternity care only. Systolic blood pressure in late pregnancy was also apparently lower in the exercise group than in the control group. These results indicate that supervised exercise training might be beneficial as a part of standard pregnancy care for overweight/obese women.Trial RegistrationClinicalTrials.gov NCT01243554

Novel, single-beat approach for determining both end-systolic pressure–dimension relationship and preload recruitable stroke work

ObjectiveThe end-systolic pressure–dimension relationship (ESPDR) and the preload recruitable stroke work (PRSW) relationship are load-insensitive measures of contractility, but their clinical application has been limited by the need to record...

Why the radial augmentation index is low in patients with diabetes: The J-HOP study

BackgroundRadial augmentation index (rAI), a marker of aortic wave reflection, is usually lower in patients with diabetes (DM) than in non-DM subjects, even though atherosclerotic change is advanced in DM. ObjectiveWe sought to explore why rAI in DM is lower than in non-DM. MethodsWe performed radial applanation tonometry in 1787 subjects who had at least one cardiovascular risk factor. The rAI was defined as [late systolic shoulder pressure amplitude (PP2)]/[radial pulse pressure (rPP)]. The late systolic shoulder blood pressure (SBP2) and PP2 of a radial pressure wave were used as estimates of the central SBP and PP (cPP), respectively. ResultsThe age (65.8 ± 9.8 vs. 65.8 ± 12.1 yrs) and mean brachial SBP (141 ± 16 vs. 141 ± 17 mmHg) were similar between the DM and non-DM groups. The rAI was significantly lower in the DM group (83.3 ± 14.1 vs. 87.3 ± 15.7%, p < 0.001), but clinic PP (62 ± 14 vs. 59 ± 14 mmHg, p < 0.001) and cPP (51 ± 15 vs. 49 ± 15 mmHg, p = 0.019) were significantly greater in the DM group than in the non-DM group. In multivariable analyses adjusting for covariates, the significant determinants of rAI were the estimated glomerular filtration rate (eGFR) (β = 0.17, p < 0.001) in the DM group, and the log-transformed homeostatic model assessment of insulin resistance (HOMA-IR) (β = −0.15, p < 0.001) in the non-DM group. The same trends were also seen for central SBP and cPP. ConclusionsThe lower rAI in DM associated with higher cPP compared to non-DM suggests proximal conduit–predominant arterial stiffening causing reduced reflection coefficients at systemic reflection sites. As renal function decreases, a cPP increase may overcome the increase of augmentation pressure in the DM group.

The Relationships Between the Arterial Stiffness Index Measured at the Radial Artery and Left Ventricular Diastolic Dysfunction in Asymptomatic High Risk Patients Without Atherosclerotic Cardiovascular Disease.

Arterial stiffness is associated with atherosclerosis and left ventricular (LV) diastolic function in general or hypertensive patients. However, the relationships between the arterial stiffness index measured at the radial artery and LV diastolic dysfunction in asymptomatic high-risk patients without atherosclerotic cardiovascular disease (ASCVD) have not been fully established.A total 532 statin-naïve patients (male:female ratio, 230:302, mean age, 56.0 ± 9.2 years) without ASCVD were enrolled from among subjects who simultaneously underwent transthoracic echocardiography and noninvasive semiautomated radial artery applanation tonometry from July 2011 to May 2014. Of these patients, 213 were categorized as the statin benefit group (Benefit) according to guidelines for blood cholesterol treatment, and the rest were placed in the nonbenefit control group (NoBenefit). Each group was subdivided into two groups (Y or N) according to antihypertensive medication administration. Thus, there were 4 groups: BenefitN (n = 80), BenefitY (n = 133), NoBenefitN (n = 251), and NoBenefitY (n = 68). There were significant differences in echocardiographic parameters of LV function and indices of arterial stiffness between the Benefit and NoBenefit groups. After adjusting for several risk factors, independent significant associations between echocardiographic parameters of LV diastolic function and arterial indices were identified with multivariate linear regression analysis in the Benefit patients.Parameters of arterial stiffness measured at the radial artery are associated with echocardiographic indices of LV diastolic function in asymptomatic high-risk patients without ASCVD. Therapies that prevent progression of arterial stiffness and reduce late-systolic pressure overload may help to reduce the prevalence of LV diastolic dysfunction in this population.

Effect of transcutaneous electrical nerve stimulation on peripheral to central blood pressure ratio in healthy subjects.

To investigate the effect of transcutaneous electrical nerve stimulation (TENS) on the arterial stiffness in healthy young adult and middle-aged men using the augmentation index (AI-x) and hemodynamic measures. Twenty-four men (12 aged 27·25±5·53years and 12 aged 54·83±5·10years) were randomly allocated to two subgroups: TENS or placebo in ganglion region for 45min. The AI-x and hemodynamic measures [late systolic blood pressure (SBP), central blood pressure (CBP), difference between P1 and P2 (ΔP) and tension time index (TTI)] were determined before and after protocols. TENS resulted in reduction of SBP in younger adults (TENSpre: 111±2; post: 105±2·2mm Hg; PLACEBOpre: 113±1·8; post: 114±2·5mm Hg; GEE, P<0·01), whereas no difference was found in middle-aged group. TENS also resulted in reduction of AI-x younger adults group (TENSpre: 56±2·8; post: 53±2%; PLACEBOpre: 55±3; post: 58±2·5%; GEE, P<0·01). ΔP and TTI were significantly decreased after the application of TENS in both groups, but significantly greater reductions in TTI and the SBP/CBP ratio were found in the group of younger adults. The acute application of ganglion TENS attenuated arterial stiffness in younger adults as well as hemodynamic measures in the middle-aged group. This method could emerge as effective therapy for the management of arterial blood pressure.

Prospective risk factors for increased central augmentation index in men and women.

Arterial wave reflections are important determinants of central pressure pulsatility and left ventricular afterload. The augmentation index (AIx) is the most widely used surrogate of arterial wave reflections. Despite multiple cross-sectional studies assessing the correlates of AIx, little prospective data exist regarding changes in AIx over time. We aimed to assess the predictors of changes in AIx over time in adults from the general population. We performed radial arterial tonometry assessments a median of 3.18 ± 0.4 years apart on 143 nondiabetic adult participants in the population-based PREVENCION study. Central AIx was obtained using the generalized transfer function of the Sphygmocor device. Predictors of the change in AIx over time were investigated. Among men (n = 67), the change in AIx was predicted by abdominal obesity (standardized β for waist circumference = 0.34; P = 0.002), impaired fasting glucose (standardized β = 0.24; P = 0.009), and the change in heart rate (standardized β = -0.78; P < 0.001). Among women (n = 76), the change in AIx was predicted by non-high-density lipoprotein cholesterol (standardized β = 0.33; P = 0.001), C-reactive protein levels (standardized β = 0.24; P = 0.02), change in mean arterial pressure (standardized β = 0.33; P = 0.001), and change in heart rate (standardized β = -0.52; P < 0.001). Metabolic and inflammatory factors predicted changes in AIx over time, with important sex differences. Metabolic factors, such as abdominal obesity and impaired fasting glucose, predicted changes in AIx in men, whereas C-reactive protein and non-high-density lipoprotein cholesterol levels predicted changes in women. Our findings highlight the impact of sex on arterial properties and may guide the design of interventions to favorably impact changes in late systolic pressure augmentation.

Pulmonary hypertension after pneumonectomy for lung cancer

We aimed to consolidate our clinical observations regarding the development of pulmonary hypertension following pneumonectomy for lung cancer. Sixty-nine of 82 initially selected patients without pulmonary or cardiac comorbidities, who underwent pneumonectomy for lung cancer between October 2009 and October 2011, accomplished our protocol. Mean patient age was 60.6 years (range 44-78 years) and 10.1% were women. Postoperative complications occurred in 16 (23.2%) patients. Mortality at 1, 12, and 18 months postoperatively was 4.3%, 15.9%, and 29%, respectively. One year postoperatively, 37.9% of patients developed mild to moderate pulmonary hypertension and 3.4% had severe pulmonary hypertension. The calculated mean pulmonary artery systolic pressure at 1, 6, and 12 months postoperatively was 21.9 ± 6.6, 27.3 ± 9.3, and 34.1 ± 14 mm Hg, respectively (p < 0.001). Receiver operating characteristic curve analysis showed a cutoff point at 35.5 mm Hg for late postoperative (at 12 months) pulmonary artery systolic pressure (sensitivity 80%, specificity 82%; p < 0.001) related to suboptimal clinical outcomes (decreased performance status or death), with a detected 18-fold risk for these patients (p < 0.001). Pulmonary hypertension may occur after pneumonectomy with its known adverse effects. Patients with late postoperative pulmonary artery systolic pressure > 35.5 mm Hg are at higher risk of a suboptimal clinical outcome.

The clinical usefulness of central hemodynamics to evaluate diastolic dysfunction in subjects without hypertension.

ObjectiveDiastolic dysfunction is associated with increased arterial stiffness in patients with hypertension. However, the role of arterial stiffness in diastolic dysfunction in subjects without hypertension has not been fully established.Materials and methodsA total of 287 subjects (male:female ratio 121:166, mean age 53.0±14.4 years) without hypertension or any heart disease who simultaneously received transthoracic echocardiography and noninvasively semiautomated radial artery applanation tonometry (with an Omron HEM-9000AI) in the Department of Internal Medicine, St Vincent’s Hospital, from July 2011 to September 2012, were enrolled in this study.ResultsA total of 147 subjects (male:female ratio 59:88, mean age 61.7±9.9 years), representing 51.2% of the 287 subjects, had diastolic dysfunction (defined as abnormal relaxation pattern of mitral inflow). There were significant differences in systolic blood pressure (BP), pulse pressure, late systolic peak pressure (SBP2), and radial augmentation index (RaAIx) between normal diastolic function and diastolic dysfunction. ΔBP was defined as systolic BP minus SBP2, because of the difference in systolic BP between the two groups. ΔBP (odds ratio [OR] 1.059, 95% confidence interval [CI] 1.005–1.115; P=0.032) and RaAIx (odds ratio 1.027, 95% CI 1.009–1.044, P=0.003) were associated with diastolic dysfunction. A receiver operating-characteristic curve showed that ΔBP (area under the curve 0.875, 95% CI 0.832–0.911) and RaAIx (area under the curve 0.878, 95% CI 0.835–0.914) were associated with diastolic dysfunction.ConclusionWe found that ΔBP and increased RaAIx were associated with diastolic dysfunction in subjects without hypertension after adjustment for age and sex. Therefore, it is suggested that noninvasive estimation of central BP may be useful to reflect diastolic dysfunction in subjects with normal peripheral BP.

Left Ventricular Responses to Acute Changes in Late Systolic Pressure Augmentation in Older Adults

Changes in the cardiovascular system with age may predispose older persons to development of heart failure with preserved ejection fraction. Vascular stiffening, aortic pressure augmentation, and ventricular-vascular coupling have been implicated. We explored the potential for acute reductions in late systolic pressure augmentation to impact left ventricular relaxation in older persons without heart failure. Sixteen older persons free of known cardiovascular disease with the exception of hypertension had noninvasive tonometry and cardiac ultrasound to evaluate central augmentation index (AI) and diastolic function at baseline and after randomized, blinded administration of intravenous B-type natriuretic peptide (BNP) and hydralazine in a crossover design. AI was significantly reduced after BNP (11.4±8.9 to -0.2±14.7%; P = 0.02) and nonsignificantly reduced after hydralazine (14.7±8.4% to 11.5±8.8%; P = 0.39). With decreased AI during BNP, a trend toward worsened myocardial relaxation by tissue Doppler imaging occurred (E' velocity pre- and post-BNP: 10.0±2.5 and 8.8±2.0cm/s, respectively; P = 0.06). There was a significant fall in stroke volume with BNP (68.5±18.3 to 60.9±18.1ml; P = 0.02), suggesting that changes in preload overwhelmed effects of afterload reduction on ventricular performance. With hydralazine, neither relaxation nor stroke volume changed. Acute changes in late systolic aortic pressure augmentation do not necessarily lead to improved systolic or diastolic function in older people. Preload may be a more important determinant of cardiac performance than afterload in older people with compensated ventricular function. The potential for changes in preload to impair rather than enhance left ventricular systolic and diastolic function in older people warrants further study. This study is registered at clinicaltrials.gov as NCT00204984.

Relationship between left ventricular diastolic function and arterial stiffness in asymptomatic patients with diabetes mellitus

Left ventricular (LV) diastolic dysfunction and increased arterial stiffness are common in patients with diabetes mellitus (DM). However, the relation between these two pathophysiological factors remains unclear. The aim of this study was to investigate the relationship between LV diastolic function and arterial stiffness as assessed with applanation tonometry. In 142 asymptomatic patients with DM (mean age 48 years, 75 (53 %) men, 72 (51 %) patients with type 2 DM) LV diastolic function was assessed with echocardiography. Arterial stiffness was evaluated measuring the aortic pulse wave velocity (PWV) whereas wave reflection was assessed measuring central systolic blood pressure (cSBP), central pulse pressure (cPP), and augmentation index (AIx) with applanation tonometry. Mean E/A ratio, E' and E/E' ratio were 1.1 ± 0.3, 8.1 ± 2.3 and 9.2 ± 3.3 cm/s, respectively. Mean PWV, mean cSBP, median cPP and mean AIx were 7.9 ± 2.4 m/s, 122 ± 17 mmHg, 40 [35-51] mmHg and 17.9 ± 12.1 %, respectively. PWV was independently associated with LV diastolic dysfunction grade (β = 0.76, p = 0.03). In contrast, measures of wave reflection, cPP, cSBP and AIx were independently related with E/A ratio, but not with the LV diastolic dysfunction grade. Parameters of arterial stiffness and wave reflection are associated with echocardiographic indices of LV diastolic function in asymptomatic patients with DM. Therapies that prevent progression of arterial stiffness and reduce late-systolic pressure overload may help to reduce the prevalence of LV diastolic dysfunction in this population.