Wen-Chol Voon

Association of Interarm Systolic Blood Pressure Difference with Atherosclerosis and Left Ventricular Hypertrophy

An interarm systolic blood pressure (SBP) difference of 10 mmHg or more have been associated with peripheral artery disease and adverse cardiovascular outcomes. We investigated whether an association exists between this difference and ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and echocardiographic parameters. A total of 1120 patients were included in the study. The bilateral arm blood pressures were measured simultaneously by an ABI-form device. The values of ABI and baPWV were also obtained from the same device. Clinical data, ABI<0.9, baPWV, echocariographic parameters, and an interarm SBP difference ≥10 mmHg were compared and analyzed. We performed two multivariate forward analyses for determining the factors associated with an interarm SBP difference ≥10 mmHg [model 1: significant variables in univariate analysis except left ventricular mass index (LVMI); model 2: significant variables in univariate analysis except ABI<0.9 and baPWV]. The ABI<0.9 and high baPWV in model 1 and high LVMI in model 2 were independently associated with an interarm SBP difference ≥10 mmHg. Female, hypertension, and high body mass index were also associated with an interarm SBP difference ≥10 mmHg. Our study demonstrated that ABI<0.9, high baPWV, and high LVMI were independently associated with an interarm SBP difference of 10 mmHg or more. Detection of an interarm SBP difference may provide a simple method of detecting patients at increased risk of atherosclerosis and left ventricular hypertrophy.

Global left ventricular longitudinal systolic strain as a major predictor of cardiovascular events in patients with atrial fibrillation

Objective Although global left ventricular longitudinal systolic strain (GLS) is a sensitive measure of left ventricular mechanics, its relationship with adverse cardiovascular (CV) events in atrial fibrillation (AF) has not been evaluated. This study sought to examine the ability of GLS in predicting CV events in AF. Design Observational cohort study. Setting Department of cardiology in a university hospital. Patients 196 persistent AF patients referred for echocardiographic examination. Main outcome measures The risk of GLS measured by index beat method for CV events was assessed by Cox proportional hazards analyses. CV events were defined as CV death, non-fatal stroke and hospitalisation for heart failure. Results There were 19 CV deaths, 12 non-fatal stroke and 28 hospitalisations for heart failure during an average follow-up of 21±10 months. Multivariate analysis showed worsening GLS (HR 1.121; 95% CI 1.023 to 1.228, p=0.014) was independently associated with increased CV events. In direct comparison, GLS outperformed left ventricular ejection fraction (LVEF) and systolic mitral annulus velocity (Sa) in predicting adverse CV events both in univariate and multivariate models (p≤0.043). Besides, the addition of GLS to a Cox model containing chronic heart failure, hypertension, age ≥75 years, diabetes, prior stroke score, estimated glomerular filtration rate, LVEF and Sa provided an additional benefit in the prediction of adverse CV events (p=0.022). Conclusions GLS was a major parameter and stronger than LVEF and Sa in predicting adverse CV events and could offer an additional prognostic benefit over conventional clinical and echocardiographic systolic parameters in AF.

Left Ventricular Tei Index: Comparison between Flow and Tissue Doppler Analyses

Background: It is still unknown whether a correlation exists between left ventricular Tei index obtained by tissue Doppler imaging and that determined by flow Doppler waveforms. This study was conducted to evaluate their relationship and to assess the positional effect on them. Methods: Twenty‐six healthy subjects and 25 patients with essential hypertension were included. On the tissue Doppler images, the time interval from the end to the onset of the mitral annular velocity pattern during diastole and the duration of the S‐wave were used to calculate tissue Doppler Tei index. Results: The tissue Doppler Tei index correlated with the flow Doppler Tei index at sitting position (r = 0.406, P = 0.003), but not at left lateral decubitus position. The limits of agreement for the Tei index measured by both methods were −0.26 to 0.62 at left lateral decubitus position and −0.09 to 0.55 at sitting position. Preload reduction associated with sitting position with dangling feet raised the Tei index both in the healthy controls [0.54 (0.14) vs 0.42 (0.12), P < 0.001] and in the hypertensives [0.53 (0.15) vs 0.46 (0.12), P = 0.005]. There was a similar positional effect on the tissue Doppler Tei index in the control subjects [0.75 (0.12) vs 0.53 (0.10), P < 0.001]. Conclusions: Tissue Doppler Tei index does not seem to be a suitable substitute for flow Doppler Tei index. Flow Doppler Tei index is preload dependent and the loading status should be taken into consideration at the application of Tei index to the evaluation of myocardial performance.

Measuring Left Ventricular Peak Longitudinal Systolic Strain from a Single Beat in Atrial Fibrillation: Validation of the Index Beat Method

BACKGROUND It is traditionally difficult to estimate left ventricular (LV) systolic function in atrial fibrillation (AF). The aim of this study was to validate the use of an index beat, the beat after the nearly equal preceding (RR1) and pre-preceding (RR2) intervals, for the measurement of LV peak longitudinal systolic strain (PLSS). The difference between RR1 and RR2 intervals of the index beat must be <60 msec. LV PLSS measured from the index beat (PLSSindex) was compared with LV PLSS measured from the conventional but time-consuming method of averaging multiple cardiac cycles (PLSSavg). METHODS Ninety-eight patients with persistent or permanent AF and resting ventricular rates ≤ 105 beats/min were prospectively included. LV PLSSindex and LV PLSSavg were obtained from two-dimensional speckle-tracking echocardiography. RESULTS LV PLSSindex had a highly significant correlation with LV PLSSavg (r = 0.970, P < .001). Bland-Altman analysis showed only small bias of 0.01%, and the 95% limits of agreement were +1.64% to -1.62%. Compared with those with lower risk scores of stroke indicated by CHADS(2) scores < 2 or CHA(2)DS(2)-VASc scores < 2, patients with higher risk scores of stroke indicated by CHADS(2) scores ≥ 2 or CHA(2)DS(2)-VASc scores ≥ 2 had lower PLSSavg and PLSSindex (P ≤ .012). CONCLUSIONS LV PLSSindex was a good alternative to LV PLSSavg in patients with AF. Use of the index beat to measure LV longitudinal systolic strain in patients with AF was as accurate as the time-consuming method of averaging multiple cardiac cycles.

Influence of different measurement time points on brachial-ankle pulse wave velocity and ankle-brachial index in hemodialysis patients.

In order to ensure that they are reliable markers of atherosclerosis and suitable for repetitive follow-up of disease progression and management responses in hemodialysis (HD) patients, brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) should be tested to see whether they change with different measurement time points. The aim of this study was to assess whether baPWV and ABI vary according to whether they are measured before HD, after HD, or on the next dialysis-free day. Eighty-nine patients undergoing regular HD were enrolled. The baPWV and ABI were measured 10–30 min before and after HD, and if patients agreed, on the next dialysis-free day. The third measurement of baPWV and ABI, performed 22±2 h after HD, was taken in 72 patients (81%). The body weight reduction after HD was 2.5±0.9 kg (p<0.001). The brachial and ankle systolic and diastolic blood pressures before HD were significantly higher than those after HD and on the next dialysis-free day (p≤0.038). Right and left baPWV increased significantly after HD (p≤0.006), but returned to the pre-dialysis level on the next dialysis-free day. However, the right and left ABI remained constant before and after HD, or on the next dialysis-free day (p≥0.498). In conclusion, despite the significant decrease in body weight and blood pressures, baPWV increased significantly after HD. In addition, baPWV, but not ABI, may vary at different measurement time points. Therefore, baPWV, but not ABI, should be assessed in a timely manner in HD patients.

Effects of Heart Rate on Brachial-Ankle Pulse Wave Velocity and Ankle-Brachial Pressure Index in Patients Without Significant Organic Heart Disease

This study evaluated the effects of heart rate (HR) on brachial-ankle pulse wave velocity (baPWV) and ankle-brachial pressure index (ABI). Thirty-two patients without significant organic heart disease underwent elective cardiac catheterization or electrophysiologic study, and were then enrolled in right atrial pacing (RAP; 11 men, 9 women; aged 48 ∓15 years) or right ventricular pacing (RVP; 6 men, 6 women, aged 45 ∓13 years) studies. Three different HR levels (90, 100, and 110 beats per minute) were paced in random order. By stepwise, multiple linear regression analysis, age, systolic blood pressure (SBP), and pulse pressure (PP) correlated positively with baseline baPWV. In the RAP group, as HR increased, baPWV and left brachial diastolic blood pressure increased significantly (p ≤0.015), while ABI, left ankle SBP, left brachial PP, and left ankle PP decreased significantly (p ≤0.013). In the RVP group, as HR increased, baPWV also increased significantly (p=0.001), while ABI, left ankle SBP, and PP decreased significantly (p ≤ 0.034). Values of baPWV and ABI may be influenced by HR in young and middle-aged patients without significant organic heart disease. When these values are used to evaluate and follow up cardiovascular risk in patients, HR changes should be considered.

Effects of atorvastatin and atorvastatin withdrawal on soluble CD40L and adipocytokines in patients with hypercholesterolaemia.

Objective — Beyond lipid lowering, statins have pleiotropic effects with favourable benefits against atherogenesis.Withdrawal of statin therapy has been demonstrated to abrogate vascular protective activity and even increase the incidence of thrombotic vascular events.The purpose of this study is to investigate the serial changes of soluble CD40 ligand (sCD40L) and two adipocytokines, adiponectin and resistin, after short-term atorvastatin therapy and withdrawal in patients with hypercholesterolaemia. Methods and results — Thirty-two patients with hypercholesterolaemia received atorvastatin 10 mg/day for 3 months. Serum lipid profiles, and levels of sCD40L, adiponectin and resistin, were assessed before and immediately after 3 months’ statin therapy. Serum levels of sCD40L and adiponectin were also measured on the 3 consecutive days after statin withdrawal. After 3 months’ statin therapy, levels of sCD40L (1.93 ± 1.13 vs. 1.30 ± 0.97 ng/mL), total cholesterol and low-density lipoprotein cholesterol (LDL-C) were all reduced significantly (p < 0.05). However, sCD40L level tended to increase towards baseline on the first and second days after statin withdrawal, but was not significantly elevated until the third day after withdrawal (1.89 ± 1.28 vs. 1.30 ± 0.97 ng/mL, p < 0.05).Total cholesterol and LDL-C levels did not increase during the 3 days of statin withdrawal. No significant changes of adiponectin and resistin levels were shown after statin therapy. Conclusions — These results indicate that the effect of statin on sCD40L level was abrogated after therapy withdrawal, and was independent of serum cholesterol level. Statin therapy did not significantly alter levels of adiponectin and resistin.

Impaired left ventricular systolic function and increased brachial-ankle pulse-wave velocity are independently associated with rapid renal function progression

Heart failure and increased arterial stiffness are associated with declining renal function. Few studies have evaluated the association between left ventricular ejection fraction (LVEF) and brachial-ankle pulse-wave velocity (baPWV) and renal function progression. The aim of this study was to assess whether LVEF<40% and baPWV are associated with a decline in the estimated glomerular filtration rate (eGFR) and the progression to a renal end point of ⩾25% decline in eGFR. This longitudinal study included 167 patients. The baPWV was measured with an ankle-brachial index-form device. The change in renal function was estimated by eGFR slope. The renal end point was defined as ⩾25% decline in eGFR. Clinical and echocardiographic parameters were compared and analyzed. After a multivariate analysis, serum hematocrit was positively associated with eGFR slope, and diabetes mellitus, baPWV (P=0.031) and LVEF<40% (P=0.001) were negatively associated with eGFR slope. Forty patients reached the renal end point. Multivariate, forward Cox regression analysis found that lower serum albumin and hematocrit levels, higher triglyceride levels, higher baPWV (P=0.039) and LVEF<40% (P<0.001) were independently associated with progression to the renal end point. Our results show that LVEF<40% and increased baPWV are independently associated with renal function decline and progression to the renal end point.

Postchallenge responses of nitrotyrosine and TNF-alpha during 75-g oral glucose tolerance test are associated with the presence of coronary artery diseases in patients with prediabetes

BackgroundMeta-analysis has demonstrated an exponential relationship between 2-hr postchallenge hyperglycemia and coronary artery disease (CAD). Pulsatile hyperglycemia can acutely increase proinflammatory cytokines by oxidative stress. We hypothesized that postchallenge proinflammatory and nitrosative responses after 75 g oral glucose tolerance tests (75 g-OGTT) might be associated with CAD in patients without previously recognized type 2 diabetes mellitus (T2DM).MethodsSerial changes of plasma glucose (PG), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and nitrotyrosine levels were analyzed during 75 g-OGTT in 120 patients (81 male; age 62 ± 11 years) before coronary angiography. Patients were classified as normal (NGT; 42%), impaired (IGT; 34%) and diabetic (T2DM; 24%) glucose tolerance by 75 g-OGTT.ResultsPostchallenge hyperglycemia elicited TNF-α, IL-6 and nitrotyrosine levels time-dependently, and 2-hr median levels of TNF-α (7.1 versus 6.4 pg/ml; P < 0.05) and nitrotyrosine (1.01 versus 0.83 μ mol/l; P < 0.05), but not IL-6 or PG, were significantly higher in patients with CAD in either IGT or T2DM groups. After adjusting risk factors and glucose tolerance status, 2-hr nitrotyrosine in highest quartiles (OR: 3.1, P < 0.05) remained an independent predictor of CAD by logistic regression analysis.ConclusionsThese results highlight postchallenge proinflammatory and nitrosative responses by 75 g-OGTT, rather than hyperglycemia per se, are associated with CAD in patients without previous recognized diabetes.

Myocardial performance index derived from brachial-ankle pulse wave velocity: a novel and feasible parameter in evaluation of cardiac performance.

BACKGROUND Right brachial pre-ejection period (rbPEP), brachial-ankle pulse wave velocity (baPWV), and right brachial ejection time (rbET) can be automatically determined from an ABI-form device. The aims of this study are to test the applicability of baPWV-derived myocardial performance index (MPI) (defined as the ratio of rbPEP divided by its own s.d. + baPWV divided by its own s.d. to rbET divided by its own s.d.) as an indicator of combined left ventricular (LV) systolic and diastolic functions. METHODS A sum of 215 patients were consecutively included. The rbPEP, baPWV, and rbET were measured using an ABI-form device and LV function was determined by echocardiography. RESULTS After a multivariate analysis, diastolic blood pressure (beta = 0.220, P < 0.001), LV ejection fraction (LVEF) (beta = -0.291, P < 0.001), transmitral E wave velocity (E) (beta = -0.106, P = 0.032), early diastolic mitral annular velocity (Ea) (beta = -0.142, P = 0.009), and ET obtained by tissue Doppler echocardiography (beta = -0.397, P < 0.001) were the major determinants of baPWV-derived MPI. The area under the curve for rbPEP, baPWV, rbET, rbPEP/rbET, and baPWV-derived MPI in prediction of Ea <8 cm/s, E/Ea >10, or LVEF <50% were 0.69, 0.76, 0.67, 0.73, and 0.83, respectively. CONCLUSIONS BaPWV-derived MPI had a significant correlation with echocardiographic LV diastolic and systolic function. It may be a novel and feasible indicator in assessment of global LV function.