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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. [ABSTRACT FROM AUTHOR]

Objectives: Increased arterial stiffness is associated with left ventricular diastolic dysfunction (LVDD), but this association may be influenced by left ventricular (LV) performance. Left ventricular hypertrophy (LVH) is not only a significant determinant of LV performance, but is also correlated with LVDD. This study is designed to compare LV diastolic function among patients divided by brachial-ankle pulse wave velocity (baPWV) and electrocardiography (ECG)-determined LVH and to assess whether increased baPWV and ECG-determined LVH are independently associated with LVDD. Methods: This cross-sectional study enrolled 270 patients and classified them into four groups according to the median value of baPWV and with/without ECG-determined LVH. The baPWV was measured using an ABI-form device. ECG-determined LVH was defined by Sokolow-Lyon criterion. LVDD was defined as impaired relaxation, pseudonormal, and restrictive mitral inflow patterns. Groups 1, 2, 3, and 4 were patients with lower baPWV and without ECG-determined LVH, lower baPWV but with ECG-determined LVH, higher baPWV but without ECG-determined LVH, and higher baPWV and with ECG-determined LVH respectively. Results: Early diastolic mitral velocity (Ea) was gradually decreased from group 1 to group 4 (p≤0.027). Patients in group 4 had the highest prevalence of LVDD (all p<0.001). After multivariate analysis, both baPWV and ECG-determined LVH were independent determinants of Ea (β=20.02, P<0.001; β= -1.77, P<0.001 respectively) and LVDD (odds ratio = 1.02, P = 0.011 and odds ratio = 3.53, P = 0.013 respectively). Conclusion: Our study showed the group with higher baPWV and ECG-determined LVH had the lowest Ea and highest prevalence of LVDD. In addition, both baPWV and ECG-determined LVH were independently associated with Ea and LVDD. Hence, assessment of arterial stiffness by baPWV and LVH by ECG may be useful in identifying the high risk group of LVDD. [ABSTRACT FROM AUTHOR]

Inappropriate left ventricular mass index (LVM) may develop as a response to particular hemodynamic and metabolic alterations. Inappropriate LVM and peripheral artery disease (PAD) characterized by abnormally low or high ankle-brachial index (ABI) are common in chronic kidney disease (CKD) patients, in whom there may be a close and cause-effect relationship. The aim of this study is to assess whether CKD and abnormal ABI has an independent and additive association with inappropriate LVM. A total of 1110 patients were included in the study. Inappropriate LVM was defined as observed LVM more than 28% of the predicted value. The ABI was measured using an ABI-form device. PAD was defined as ABI <0.9 or ≥1.3 in either leg. Multivariate analysis showed that patients with estimated glomerular filtration rate (eGFR) <45 ml/min/1.73 m² (odds ratio [OR], 1.644; P = 0.011) and PAD (OR, 2.082; P = 0.002) were independently associated with inappropriate LVM. The interaction between eGFR <45 ml/min/1.73 m² and PAD on inappropriate LVM was statistically significant (P = 0.044). Besides, eGFR<45 ml/min/1.73 m² (change in observed/predicted LVM, 19.949; P,0.001) and PAD (change in observed/predicted LVM, 11.818; P = 0.003) were also significantly associated with observed/predicted LVM. Our findings show that eGFR <45 ml/min/1.73 m² and PAD are independently and additively associated with inappropriate LVM and observed/predicted LVM. Assessments of eGFR and ABI may be useful in identifying patients with inappropriate LVM. [ABSTRACT FROM AUTHOR]

Abnormally low and high ankle-brachial indices (ABIs) are associated with high cardiovascular morbidity and mortality in patients with chronic kidney disease (CKD), but the mechanisms responsible for the association are not fully known. This study is designed to assess whether there is a significant correlation between abnormal ABI and echocariographic parameters in patients with CKD stages 3-5. A total of 684 pre-dialysis CKD patients were included in the study. The ABI was measured using an ABI-form device. Patients were classified into ABI ≥0.9, ≥0.9 to ,1.3, and <1.3. Clinical and echocariographic parameters were compared and analyzed. Compared with patients with ABI of <0.9 to <1.3, the values of left ventricular mass index (LVMI) were higher in patients with ABI ≥0.9 and ABI ≥1.3 (P=0.004). After the multivariate analysis, patients with ABI ,0.9 (β99, P = 0.004) and ABI ≥1.3 (β = 0.143, P<0.001) were independently associated with increased LVMI. Besides, increased LVMI (odds ratio, 1.017; 95% confidence interval, 1.002 to 1.033; P = 0.031) was also significantly associated with ABI ,0.9 or ABI ≥1.3. Our study in patients of CKD stages 3-5 demonstrated abnormally low and high ABIs were positively associated with LVMI. Future studies are required to determine whether increased LVMI is a causal intermediary between abnormal ABI and adverse cardiovascular outcomes in CKD. [ABSTRACT FROM AUTHOR]

The P wave parameters measured by 12-lead electrocardiogram (ECG) are commonly used as noninvasive tools to assess for left atrial enlargement. There are limited studies to evaluate whether P wave parameters are independently associated with decline in renal function. Accordingly, the aim of this study is to assess whether P wave parameters are independently associated with progression to renal end point of ≥25% decline in estimated glomerular filtration rate (eGFR). This longitudinal study included 166 patients. The renal end point was defined as ≥25% decline in eGFR. We measured two ECG P wave parameters corrected by heart rate, i.e. corrected P wave dispersion (PWdisperC) and corrected P wave maximum duration (PWdurMaxC). Heart function and structure were measured from echocardiography. Clinical data, P wave parameters, and echocardiographic measurements were compared and analyzed. Forty-three patients (25.9%) reached renal end point. Kaplan-Meier curves for renal end point-free survival showed PWdisperC > median (63.0 ms) (log-rank P = 0.004) and PWdurMaxC > median (117.9 ms) (log-rank P,0.001) were associated with progression to renal end point. Multivariate forward Cox-regression analysis identified increased PWdisperC (hazard ratio [HR], 1.024; P = 0.001) and PWdurMaxC (HR, 1.029; P = 0.001) were independently associated with progression to renal end point. Our results demonstrate that increased PWdisperC and PWdurMaxC were independently associated with progression to renal end point. Screening patients by means of PWdisperC and PWdurMaxC on 12 lead ECG may help identify a high risk group of rapid renal function decline. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Coronary collateral circulation plays an important role to protect myocardium from ischemia, preserve myocardial contractility and reduce cardiovascular events. Chronic kidney disease (CKD) is associated with poor coronary collateral development and cardiovascular outcome. However, limited research investigates the predictors for collateral development in the CKD population. Methods: We evaluated 970 consecutive patients undergoing coronary angiography and 202 patients with CKD, defined as a glomerular filtration rate less than 60 ml/min/1.73 m2, were finally analyzed. The collateral scoring system developed by Rentrop was used to classify patients into poor (grades 0 and 1) or good (grades 2 and 3) collateral group. Results: The patients with poor collateral (n = 122) had a higher incidence of hypertension (82% vs 63.8%, p = 0.005), fewer diseased vessels numbers (2.1 ± 0.9 vs 2.6 ± 0.6, p < 0.001) and a trend to be diabetic (56.6% vs. 43.8%, p = 0.085) or female sex (37.7% vs. 25.0%, p = 0.067). Multivariate analysis showed hypertension (odd ratio (OR) 2.672, p = 0.006), diabetes (OR 1.956, p = 0.039) and diseased vessels numbers (OR 0.402, p < 0.001) were significant predictors of poor coronary collaterals development. Furthermore, hypertension and diabetes have a negative synergistic effect on collateral development (p = 0.004 for interaction). Conclusions: In the CKD population hypertension and diabetes might negatively influence the coronary collaterals development. [ABSTRACT FROM AUTHOR]

Nicorandil is an antianginal agent with nitrate-like and ATP-sensitive potassium channel activator properties. After activation of potassium channels, potassium ions are expelled out of the cells, which lead to membrane hyperpolarization, closure of voltage-gated calcium channels, and finally vasodilation. We present a uremic case suffering from repeated junctional bradycardia, especially before hemodialysis. After detailed evaluation, nicorandil was suspected to be the cause of hyperkalemia which induced bradycardia. This case reminds us that physicians should be aware of this potential complication in patients receiving ATP-sensitive potassium channel activator. [ABSTRACT FROM AUTHOR]

Functional coronary artery occlusion due to type A aortic dissection has rarely been reported in the literature. We report a case of aortic dissection presenting with anterior ST elevation. Coronary angiography revealed normal findings and chest computed tomography-confirmed type A aortic dissection. Emergent surgery was performed and dissection involving the right coronary artery orifice was found. An electrocardiogram after the operation revealed resolution of anterior ST elevation. The mechanism of initial anterior but not inferior ST elevation should be related to functional obstruction of the left main coronary artery by intimal flap and reciprocal ST-T change over inferior leads. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Previous studies which included patients with preserved left ventricular (LV) systolic function demonstrated that arterial stiffness progressively increased as LV diastolic function decreased. However, it was unknown whether this correlation was still present in a heterogeneous study population involving patients with a wide range of LV systolic function. Seventy-five patients with depressed LV systolic function were consecutively included and 192 patients with preserved LV systolic function were randomly selected from subjects arranged for echocardiography examination. Brachial-ankle pulse wave velocity (baPWV) was measured using an ABI-form device. Of the 267 subjects (mean age 58 ± 14 years) included in the study, 105 had normal diastolic function, 74 had impaired relaxation, and 60 had pseudonormal and 28 restrictive diastolic dysfunction. BaPWV was only lower in patients with normal diastolic function than in those with abnormal diastolic function ( p ≤ 0.001). It did not gradually rise as diastolic dysfunction grade increased. Multivariate analysis showed that increased age and systolic blood pressure and decreased LV ejection fraction, transmitral A velocity, and left atrial volume index ( p ≤ 0.039) were correlated with increased baPWV. Our study showed that there were no positive correlation between echocardiographic LV diastolic parameters and baPWV. BaPWV did not progressively rise with increasing LV diastolic dysfunction grade. Therefore, patients with advanced LV diastolic dysfunction may not have increased arterial stiffness. [ABSTRACT FROM AUTHOR]

BackgroundRight 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.MethodsA 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.ResultsAfter a multivariate analysis, diastolic blood pressure (β = 0.220, P < 0.001), LV ejection fraction (LVEF) (β = −0.291, P < 0.001), transmitral E wave velocity (E) (β = −0.106, P = 0.032), early diastolic mitral annular velocity (Ea) (β = −0.142, P = 0.009), and ET obtained by tissue Doppler echocardiography (β = −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.ConclusionsBaPWV-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.American Journal of Hypertension 2009; doi:10.1038/ajh.2009.94American Journal of Hypertension 2009; 22, 8, 871–876. doi:10.1038/ajh.2009.94 [ABSTRACT FROM AUTHOR]

BackgroundWall shear stress (WSS) has been shown to be a critical determinant of vessel diameter implicated in vascular remodeling and atherogenesis. Carotid intima-media thickness (IMT), resistive index (RI), and pulsatility index (PI) have been used as relevant indictors for carotid atherosclerosis. The study aimed to investigate the relationship between hemodynamic parameters in the common carotid artery (CCA) and the severity of carotid atherosclerosis in untreated hypertensive patients.MethodsDuplex ultrasound was performed in 64 untreated hypertensive patients and 16 age-matched normotensive control subjects. Morphologic and hemodynamic parameters of CCA, including peak and mean WSS, RI, PI, and IMT were calculated after measuring internal diameter (ID) and flow velocity of CCA.ResultsSubjects with hypertension had lower peak and mean WSS than did normotensive control subjects (P < 0.05). Both carotid RI and PI were found to correlate inversely with mean WSS in hypertensive subjects. There was no correlation between carotid IMT and WSS. Stepwise multiple regression analysis for carotid RI and PI after adjustment for age, carotid IMT, and high sensitivity C-reactive protein (hsCRP) showed that mean WSS was an independent determinant of RI and PI.ConclusionsHigh carotid atherosclerotic indexes as expressed by both RI and PI are associated with low WSS in CCA. These findings indicate that local shear stress is associated with altered vascular pulsatility and resistance. Consequent alteration in local vascular dynamics could be an underlying mechanism for the progression of atherosclerosis.American Journal of Hypertension 2009; doi:10.1038/ajh.2009.77American Journal of Hypertension 2009; 22, 7, 705–710. doi:10.1038/ajh.2009.77 [ABSTRACT FROM AUTHOR]

OBJECTIVES: To test the association between angiotensin-converting enzyme (ACE) insertion or deletion (I/D) polymorphism and decline of renal function in people aged 60 and older. DESIGN: Population-based prospective study with 4-year follow-up. SETTING: Department of Internal Medicine and Family Medicine, Kaohsiung Medical University (KMU) Hospital and Graduate Institute of Medicine and Public Health, KMU. PARTICIPANTS: Of 1,500 people screened, 193 subjects were enrolled, and 144 completed 4 years of follow-up, 112 non-diabetic normotensive elderly people were analyzed. MEASUREMENTS: Subjects received biochemistry examination at baseline and at 2- and 4-year follow-ups. Serum creatinine and calculated renal parameters, including the Cockroft-Gault (CG) formula, the Jelliffe formula, and the Modification of Diet in Renal Disease (MDRD) Study equation, were used. Genetic polymorphism was analyzed according to the polymerase chain reaction. RESULTS: The mean age±standard deviation of the subjects was 71.9±3.7 (range 60–81). Serum creatinine, CG creatinine clearance (CrCl), Jelliffe CrCl, and MDRD glomerular filtration rate (GFR) were significantly lower at the 2- and 4-year follow-ups (all P≤.001). At the 4-year follow-up, the magnitude of declines of the above four renal parameters was significantly higher in subjects with the ACE D allele than in the non-D-allele carriers ( P=.01, .01, .04, and .01 for creatinine, CG CrCl, Jelliffe CrCl, and MDRD GFR, respectively). This association was still significant in multivariate analyses ( P≤.02 for all parameters). CONCLUSION: This longitudinal study showed the ACE I/D gene polymorphism might modulate renal function decline in elderly Chinese. This provides further knowledge essential in the assessment of renal disease and determination of renal function in older Chinese. [ABSTRACT FROM AUTHOR]

Background. Cross-sectional studies investigated the impact of renin-angiotensin system (RAS) gene polymorphism on left ventricular mass index (LVMI) with conflicting results. We conducted a longitudinal study to investigate the influence of the angiotensin-converting enzyme (ACE) insertion/deletion (l/D) and angiotensinogen (AGT) M235T and angiotensin 11 type 1 receptor (ATI R) A1166C gene polymorphisms on the LVMI and geometry. Methods. Of 1500 people screened, 110 nondiabetic normotensive elderly Chinese persons were recruited and received echocardiography at baseline and at the 2nd and 4th year follow-up. No participants had a history of organic heart disease or chronic medication. The gene polymorphisms were analyzed by using polymerase chain reaction. Results. Participant age was 71.9 ± 3.9 years (range 60-81 years). The prevalence of concentric remodeling, eccentric hypertrophy, and concentric hypertrophy was significantly increased as well as LVMI after 4 years (all p < .05). These changes and the magnitude of LVMI increase were significantly higher in participants carrying the ACE D allele than non-D-allele carriers (all p < .05). This association was still significant in multivariate analyses (p < .02). A similar analysis showed a borderline significance in the ATI R but not in the AGT gene polymorphism. Conclusions. This longitudinal study showed that the aging process was associated with an increase of LVMI and changes of geometry. The RAS gene polymorphism, especially the ACE D allele, might modulale these changes in the Chinese population. This provides further knowledge that is essential in the assessment of cardiac disease and the determination of the left ventricular structure in older persons. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Statin therapy can reduce the biosynthesis of both cholesterol and coenzyme Q_{10} by blocking the common upstream mevalonate pathway. Coenzyme Q_{10} depletion has been speculated to play a potential role in statin-related adverse events, and withdrawal of statin is the choice in patients developing myotoxicity or liver toxicity. However, the effect of statin withdrawal on circulating levels of coenzyme Q_{10} remains unknown. Twenty-six patients with hypercholesterolemia received atorvastatin at 10 mg/day for 3 months. Serum lipid profiles and coenzyme Q_{10} were assessed before and immediately after 3 months and were also measured 2 and 3 days after the last day on the statin. After 3 months' atorvastatin therapy, serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and coenzyme Q_{10} (0.43 ± 0.23 to 0.16 ± 0.10 μg/mL) were all significantly reduced (all p < 0.001). On day 2 after the last atorvastatin, the coenzyme Q_{10} level was significantly elevated (0.37 ± 0.16 μg/mL) and maintained the same levels on day 3 (0.39 ± 0.18 μg/mL) compared with those on month 3 (both p< 0.001), while TC and LDL-C did not significantly change within the same 3 days. These results suggest that statin inhibition of coenzyme Q_{10} synthesis is less strict than inhibition of cholesterol biosynthesis. [ABSTRACT FROM AUTHOR]

To evaluate whether isovolumic relaxation flow propagation velocity (IRFPV) is independent of preload alterations, 41 healthy subjects (35 ± 7 years) were included for Doppler examinations at three different positions, i.e., supine, Trendelenburg, and reverse Trendelenburg. A positional difference was detected in the peak velocity of the transmitral early diastolic flow wave (P = 0.012) and the peak velocities of both early (P = 0.004) and late (P = 0.007) diastolic mitral annular velocity waves. In contrast, there was no positional difference in the early diastolic inflow propagation velocity or IRFPV. In conclusion, IRFPV is a preload-independent Doppler parameter. [ABSTRACT FROM AUTHOR]

Background: Tei index obtained from tissue Doppler echocardiography (TDE-Tei index) has an inherent advantage of recording its systolic and diastolic components simultaneously on the same cardiac cycle. The aims of this study are to evaluate whether TDE-Tei index also exerts a correlation with left ventricular (LV) systolic and diastolic function and filling pressure and to see whether it can effectively identify the pseudonormal/restrictive mitral filling pattern. Methods: Echocardiographic examination was performed in 243 consecutive patients. These patients were classified into three groups as normal, abnormal relaxation, and pseudonormal/restrictive groups according to the transmitral E/A-wave velocity (E/A), early diastolic velocity of lateral mitral annulus (Ea) and E/Ea. Results: Standard Doppler indices of LV filling such as E, A, E/A, and E-wave deceleration time had a bimodal distribution, but Ea decreased and E/Ea and TDE-Tei index increased progressively with worsening of LV diastolic function. The sensitivity and specificity of TDE-Tei index >0.51 in the discrimination of pseudonormal/restrictive filling pattern were 85% and 96%, respectively. After stepwise multiple linear regression analysis, TDE-Tei index had a significant negative correlation with Ea (β=−0.296, P < 0.001) and ejection fraction (β=−0.293, P < 0.001) and positive correlation with E/Ea (β= 0.235, P = 0.001). Conclusions: TDE-Tei index increased with worsening of LV diastolic function and can effectively identify the pseudonormal/restrictive mitral inflow pattern. It also correlated with the echocardiographic parameters of LV systolic and diastolic function and filling pressure. It suggests that TDE-Tei index is a simple and feasible marker in assessing global LV function. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background and objective: Hypertension is very prevalent in the Chinese population in Taiwan. Chinese people frequently experience bothersome cough when receiving angiotensin-converting enzyme (ACE) inhibitors, and angiotensin II (AT1) receptor antagonists are thus relatively more frequently used in this context. In this trial we studied the effectiveness of a new AT1 receptor antagonist, olmesartan, in the treatment of Chinese patients with mild-to-moderate essential hypertension. Patients and methods: The present study was a double-blind, randomised, multicentre trial to compare the efficacy and safety profiles of two AT1 receptor antagonists, olmesartan and losartan, in the treatment of Chinese patients with mild-to-moderate essential hypertension. 126 adults were randomised to receive either once-daily olmesartan 20mg or once-daily losartan 50mg for 12 weeks. There were 49 evaluable patients in the olmesartan group and 57 in the losartan group. Results: At baseline, neither diastolic (DBP) nor systolic (SBP) blood pressures were significantly different between the two study groups. Trough blood pressures were measured and recorded for the evaluation of treatment effect. After drug treatment for 4, 8 and 12 weeks, SBP and DBP values were significantly decreased in both groups of patients. However, both SBP and DBP were significantly lower in the olmesartan group than in the losartan group after treatment. At the end of treatment, DBP values were 87.0 ± 8.6mm Hg versus 91.6 ± 8.7mm Hg (p < 0.001) and SBP values were 129.5 ± 12.6mm Hg versus 135.4 ± 12.1mm Hg (p < 0.001) in the olmesartan and losartan groups, respectively. After 4 weeks of treatment, the reduction in BP values was larger in the olmesartan group than in the losartan group (decreases in DBP of 12.1 ± 8.4mm Hg vs 7.2 ± 6.8mm Hg [p < 0.005] and in SBP of 15.1 ± 13.0mm Hg vs 10.3 ± 10.1mm Hg [p < 0.05] for the olmesartan and losartan groups, respectively). Patients treated with either drug experienced only mild adverse reactions, such as dizziness, cough, headache and neck pain, all of which occurred at low frequencies. There were no significant changes in laboratory parameters. Conclusion: Both olmesartan and losartan are effective and safe in the treatment of Chinese patients with mild-to-moderate essential hypertension. Olmesartan 20mg once daily is more potent and has a more rapid antihypertensive effect than losartan 50mg once daily in the treatment of mild-to-moderate hypertension in Chinese patients. [ABSTRACT FROM AUTHOR]

Background: Inhomogenous left ventricular activation–inactivation has been suggested to play a role in the genesis of segmental early relaxation and in turn of isovolumic relaxation flow (IRF). The spatial distribution of conduction system in the left ventricle leads to heterogenous activation sequence even in healthy subjects. This study was conducted to evaluate our hypothesis that IRF should be ubiquitous in healthy subjects. Methods: This prospective study included 126 healthy subjects (aged 15–81 years) free of acute or chronic illness by history and physical examination. No significant abnormality appeared in the resting 12-lead electrocardiogram or transthoracic echocardiogram. With the pulsed-wave Doppler echocardiography, the sample volume was placed at the mid-ventricle to detect the IRF. Results: An apically directed IRF, with the velocity 17–101 cm/sec and the duration 57–145 ms, could be detected in all the study subjects. There was no inter-sex difference in such characteristics of IRF. However, its duration and velocity got longer and higher with aging. The fractional shortening of the left ventricle and the interventricular septal thickness were stepwisely selected as the determinants of the IRF velocity, and the transmitral E-to-A wave velocity ratio, the left ventricular inflow propagation velocity, and the interventricular septal thickness as the determinants of the IRF duration. Conclusions: IRF is ubiquitous in healthy subjects. Both the duration and the velocity of IRF present an aging trend and may be mainly related to left ventricular diastolic and systolic performance, respectively.(ECHOCARDIOGRAPHY, Volume 21, October 2004) [ABSTRACT FROM AUTHOR]

Adenosine has a potent negative dromotropic effect. However, comparative effects of adenosine on the three pathways of atrioventricular (AV) nodal reentry remain unclear. In this study, we sought to determine the effects of adenosine on the antegrade fast, antegrade slow, and retrograde fast pathway conduction in patients with AV nodal reentrant tachycardia (AVNRT). Twenty patients with common slow-fast AVNRT (mean cycle length 360 ± 49 ms) were studied. The effects of adenosine on the antegrade slow pathway and on the retrograde fast pathway conduction were determined during sustained AVNRT and constant right ventricular pacing at identical cycle lengths (mean 360 ± 49 ms), respectively. Incremental doses of adenosine were rapidly administered: initial dose of 0.5 mg, followed by stepwise increases of 0.5 or 1.0 mg given at 5-min intervals until termination of AVNRT or second-degree ventriculoatrial block occurred. After the antegrade slow pathway conduction was selectively and completely ablated by radiofrequency catheter ablation, the effect of adenosine on the antegrade fast pathway conduction was evaluated. The dose-response curve of adenosine and the dose of adenosine required to produce AV or ventriculoatrial block among the representative three conduction pathways were compared. The dose-response curve for the effect of adenosine on the antegrade fast pathway lies to the left and upward to that of the effect of adenosine on the antegrade slow pathway which in turn lies to the left and upward to that of the retrograde fast pathway. The mean dose of adenosine required to produce conduction block at antegrade fast, antegrade slow, and retrograde fast pathways were 1.4 ± 0.5, 4.2 ± 1.6, and 8.5 ± 2.6 mg, respectively (p < 0.01). Adenosine has a differential potency to depress antegrade fast, antegrade slow, and retrograde fast pathway conduction in patients with AVNRT. The depressant effect of adenosine on the antegrade fast pathway is more potent than that on the antegrade slow pathway which in turn is more potent than that on the retrograde fast pathway conduction.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Discusses the clinical and electrophysiologic mechanisms of exercise-induced ventricular tachyarrhythmia. Development of ventricular premature beats during exercise; Means of preventing the recurrence of ventricular tachycardia; Association of tachyarrhythmias with acute myocardial ischemia.