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Wave intensity (WI) is a novel hemodynamic index, which is defined as (d P/d t) x (d U/d t) at any site of the circulation, where d P/d t and d U/d t are the derivatives of blood pressure and velocity with respect to time, respectively. However, the pathophysiological meanings of this index have not been fully elucidated in the clinical setting. Accordingly, we investigated this issue in 64 patients who underwent invasive evaluation of left ventricular (LV) function. WI was obtained at the right carotid artery using a color Doppler system for blood velocity measurement combined with an echo-tracking method for detecting vessel diameter changes. The vessel diameter changes were automatically converted to pressure waveforms by calibrating its peak and minimum values by systolic and diastolic brachial blood pressures. The WI of the patients showed two sharp positive peaks. The first peak was found at the very early phase of LV ejection, while the second peak was observed near end-ejection. The magnitude of the first peak of WI significantly correlated with the maximum rate of LV pressure rise (LV max. d P/d t) (r = 0.74, P << 0.001). The amplitude of the second peak of WI significantly correlated with the time constant of LV relaxation (r = -0.77, P << 0.001). The amplitude of the second peak was significantly greater in patients with the inertia force of late systolic aortic flow than in those without the inertia force (3,080 +/- 1,741 vs 1,890 +/- 1,291 mmHg m s(-3), P << 0.01). These findings demonstrate that the magnitude of the first peak of WI reflects LV contractile performance, and the amplitude of the second peak of WI is determined by LV behavior during the period from late systole to isovolumic relaxation. WI is a noninvasively obtained, clinically useful parameter for the evaluation of LV systolic and early diastolic performance at the same time.

The Japanese Coronary-prone Behavior Scale (JCBS) is a questionnaire developed by the Eastern Collaborative Group Study (ECGS), a multi-center study of coronary-prone behavior among Japanese men in Japan. From the JCBS, a subscale was extracted consisting of 9 items that were independently associated with the presence of coronary artery disease (CAD) in patients undergoing coronary angiography (CAG). The subscale, named Scale C, represents job-centered lifestyle, social dominance, and suppressed overt type A behavior. To further validate the association of Scale C with CAD among Japanese men, the present study examined if such an association would be observed in a newly sampled population. The JCBS was carried out by 311 men undergoing CAG. The association between Scale C score and the presence of CAD was evaluated with logistic regression analysis that included established coronary risk factors. The Scale C score was significantly higher in subjects with CAD than in those without and stepwise multivariate logistic regression showed that the Scale C score was associated with the presence of CAD independent of age, low-density lipoprotein cholesterol, diabetes mellitus, and obesity. These results indicate that the Scale C score is independently associated with the presence of CAD even among a newly sampled population of Japanese men undergoing CAG. Scale C may reflect an important feature of coronary-prone behavior among Japanese men.

The mechanism of emergence and the clinical significance of apically directed intraventricular flow during isovolumic relaxation were investigated. The relation between the spatial distribution of the flow and left ventricular (LV) apical wall motion abnormality, as well as LV performance, was studied in 97 patients who underwent cardiac catheterization for evaluation of chest pain. According to the distribution of the flow, the patients were classified into the following 3 groups: flow observed in the whole area between the tip of the papillary muscle and the apex (spread flow) (n = 38), flow observed in the same area that did not fill the whole area (localized flow) (n = 15), and no apparent flow observed in the area (without flow) (n = 44). An absence of flow disclosed apical asynergy with a sensitivity of 97% and specificity of 87%. The time constant of LV relaxation was significantly shorter in patients with spread flow than in those without flow. A significant difference was also observed in end-systolic volume index (18.8 +/- 6.8 vs 30.9 +/- 7.7 vs 42.3 +/- 20.2 mL/m(2), spread flow < localized flow < without flow, P <.05) among the 3 groups. The propagation velocity of LV early diastolic filling flow was significantly greater in patients with spread flow (47.0 +/- 8.3 cm/s) than in those with localized flow (30.7 +/- 7.8 cm/s) or without flow (28.6 +/- 7.8 cm/s) (P <.001). These findings indicate that the greater magnitude of LV elastic recoil and the faster LV relaxation in patients without LV apical asynergy produce apically directed intraventricular flow during isovolumic relaxation, enhancing the speed of LV early diastolic filling. Apically directed intraventricular flow during isovolumic relaxation may play an important role as a mediator of better LV systolic performance and LV relaxation to LV early diastolic filling. Absence of apically directed intraventricular flow during isovolumic relaxation is a manifestation of LV apical asynergy and global LV dysfunction from end systole to early diastole.

Study Objectives: We examined whether autonomic functions assessed by heart rate variability (HRV) during standardized head-up tilt testing (HUTT) predict risk for death in stable patients with coronary artery disease (CAD)., Design and Setting: Retrospective cohort study in medium-sized university general hospital., Measurements and Results: In a cohort of 250 patients with CAD who were undergoing elective coronary angiography, we analyzed HRV during standardized HUTT under paced breathing with discontinuation of treatment with all medications. During a subsequent mean follow-up period of 99 months, there were 13 cardiac deaths and 12 noncardiac deaths. Cox regression analysis adjusted for cardiovascular risks revealed that increased postural change (supine to upright) in the power of low-frequency component (LF) power predicted an increased risk for cardiac death (relative risk [per 1-ln ms(2) increment], 4.36; 95% confidence interval, 1.64 to 11.6), while neither the high-frequency component nor its response to HUTT predicted any form of death. When the patients were trichotomized by the level of postural LF change (large drop, < or = - 0.6 ln[ms(2)]; small drop and rise, > 0 ln[ms(2)]), the three groups did not differ in terms of clinical features or CAD severity at baseline or coronary interventions during the follow-up period; however, the 8-year cardiac mortality rates were 0%, 6%, and 12%, respectively (p = 0.008 [log rank test]). Additionally, the difference was enhanced when analyzed excluding 64 patients who had been treated with a beta-blocker during the follow-up period (0%, 7%, and 15%, respectively; p = 0.006 [log rank test])., Conclusions: The postural response of HRV predicts the risk for death in patients with CAD. Postural LF increase (LF rise), in particular, is an independent risk factor for cardiac death.

An abnormal relaxation pattern in transmitral flow velocity waveforms has been observed in older healthy subjects as well as in patients with heart disease. Accordingly, we investigated whether the hemodynamic differences between patients with coronary artery disease (CAD) with an abnormal relaxation pattern in transmitral flow (ratio of E-wave to A-wave velocities < 1.0) and healthy older subjects with an abnormal relaxation pattern can be distinguished with the use of mitral annular velocity (MAV) during early diastole. We measured MAV in the longitudinal direction of the heart during early diastole by M-mode color tissue Doppler imaging in 24 patients with atypical chest pain (defined as healthy subjects in this study) and 70 patients with CAD who underwent cardiac catheterization. In all patients a time constant of left ventricular pressure decay (tau) and the left ventricular (LV) end-systolic volume index were also measured. Twenty-one healthy subjects and 59 patients with CAD had an abnormal relaxation pattern in their transmitral flow. The age, heart rate, mean blood pressure, and ratio of E-wave to A-wave velocities were not different between the two groups. However, the tau was longer and the LV end-systolic volume index was greater in patients who had an abnormal relaxation pattern with CAD than in healthy subjects with an abnormal relaxation pattern. The MAV during early diastole was lower in the former than in the latter (5.8 +/- 1. 9 vs 9.8 +/- 1.9 cm/s, P <.001). Mitral annular velocity during early diastole by M-mode color tissue Doppler imaging can detect the differences in LV relaxation and LV systolic performance between the abnormal relaxation pattern with CAD and the physiologically abnormal relaxation pattern with aging, providing further information regarding the meaning of an LV abnormal relaxation pattern.

In Japan the type A behavior pattern, particularly its component of hostility, is known to have less value as a risk for coronary artery disease (CAD) than in the United States. We developed a questionnaire (Japanese Coronary-prone Behavior Scale [JCBS]) to investigate the behavioral correlates with CAD among contemporary Japanese persons. The JCBS was administered to 419 Japanese men undergoing coronary angiography; 310 of them had angiographic or clinical evidence or both of CAD, and 109 had no evidence of CAD. The group with CAD had more coronary risk factors than the group without CAD, but the two groups did not differ in type A behavior pattern as assessed with the Jenkins Activity Survey. Stepwise discriminant analysis, in which standard coronary risk factors were forced into the model, revealed that inclusion of nine JCBS items (scale C) in the model resulted in the best discrimination between the two groups. Cross-validation results showed that the error-rate estimates for the discriminant models that consisted only of standard coronary risk factors, only of scale C items, and of their combination were 34.7, 32.4, and 27.0%, respectively. The scale C items represented a job-centered lifestyle, social dominance, and suppressed overt type A behaviors. These results indicate that an independent behavior pattern prone to CAD is discernible among Japanese men and suggest that the behavior pattern may contain characteristics that can be differentiated from those that constitute the type A behavior pattern.

Reproducibility of circadian rhythm of variability in heart rate was studied in 40 patients with stable coronary artery disease who underwent 48-hour ambulatory electrocardiographic recordings at baseline (time 1) and after 4 months (time 2). The standard deviation of the R-R interval and the low-frequency (0.04 to 0.15 Hz) and high-frequency (0.15 to 0.45 Hz) components of variability in heart rate were assessed every 5 minutes. In 35 patients a significant circadian rhythm was observed at both time 1 and time 2 in the standard deviation of the R-R interval, with the acrophase occurring at around 5:00 AM, in the high-frequency amplitude with the acrophase around 3:00 AM, and in the low-frequency/high-frequency ratio with the acrophase around noon. In these patients, parameters of circadian rhythm (mesor, amplitude, and acrophase) showed good within-individual reproducibility with an intraclass correlation coefficient of 0.63 to 0.95 (p < 0.001 for all). In the patients who showed inconsistency about the significance of circadian rhythm between time 1 or time 2, the amplitude of circadian rhythm, even if significant, was found in the lowest five values in the distribution. We conclude that the circadian rhythms of cardiac autonomic activity are stable over time within individual patients with stable coronary artery disease.

Forty-six patients with documented coronary artery disease were studied to examine the relation of cardiovascular reactivity to mental stress and cardiac vagal activity. Cardiac vagal activity was measured by means of frequency-domain analysis of heart rate variability with 48-hour out-of-hospital Holter monitoring. The amplitude of the high-frequency component (0.16 to 0.40 Hz) of heart rate variability is considered to be an index of cardiac vagal activity. Cardiovascular reactivity was measured in the laboratory during a 3-minute public speaking task. Results revealed that (1) the amplitude of the high-frequency component was significantly higher during sleep (24.6 +/- 11.3 ms) than during waking (18.2 +/- 8.0 ms) (p = 0.002); (2) compared to subjects with low diastolic blood pressure reactivity, those who displayed high diastolic blood pressure reactivity exhibited a significantly lower amplitude of the high-frequency component (19.2 +/- 6.9 vs 23.4 +/- 9.6 ms, p = 0.03). These results indicate that decreased cardiac vagal activity may contribute to the exaggerated diastolic blood pressure reactivity to mental stress in patients with coronary artery disease.

Coronary risk factors were assessed in 186 consecutive patients who received coronary angiography. The severity of coronary luminal narrowing was scored as the coronary sclerosis index (CSI). Patients were divided into normal coronary arteries (N, n = 72), coronary sclerosis without infarction (C, n = 73) and previous myocardial infarction (MI, n = 41). The CSI increased with age. A significant difference in serum triglycerides, HDL cholesterol and atherogenic index was observed between Groups C or MI and N. Multivariate analysis revealed that CSI had correlated with total- and HDL-cholesterol, uric acid and age in subjects under 55 years; and with age, blood sugar, factor H and HDL cholesterol in those of 55 years or over. When patients were classified by their total and LDL cholesterol level, a significantly different CSI was found between the desirable and high cholesterol levels in subjects under the age of 55, but it was not significant in those over 55. Therefore, disorders in lipid metabolism should be corrected in early middle age.

We analyzed the spectral components of RR interval variability under controlled respiration (15 breaths/min) in 56 patients (age range, 35-73 years) referred for coronary angiography; 14 patients had multivessel disease (group M), 21 had one-vessel disease (group S), and 21 had nonsignificant disease or normal coronary artery (group N). There were 43 healthy controls (age range, 36-71 years) (group C). The patients had no clinical evidence of heart failure, hypertension, diabetes mellitus, or acute stage of infarction and had taken no medication for 3 days. The autoregressive power spectral density of RR interval variability contains two major components, respiratory sinus arrhythmia (RSA) (0.25 Hz) and Mayer wave-like sinus arrhythmia (MWSA) (0.04-0.15 Hz), which have magnitudes that are quantitative markers of cardiac vagal activity and sympathetic activity with vagal modulation, respectively. We represented the magnitudes by the coefficient of component variance (CCV), which provided the amplitude relative to the mean RR interval. The age- and sex-adjusted mean of CCVRSA significantly decreased with advancing angiographic severity (1.64 +/- 0.09%, 1.66 +/- 0.12%, 1.22 +/- 0.13%, and 0.81 +/- 0.16% for groups C, N, S, and M, respectively) (p = 0.0001). The CCVRSA was unrelated to left ventricular function, previous myocardial infarction, or stenosis of any specific artery including the sinoatrial and atrioventricular node arteries. The CCVMWSA decreased only in group M (p = 0.0462). These results indicate that coronary artery disease is associated with vagal dominant impairment in autonomic cardiac function and that reduction in the vagal cardiac function correlates with the angiographic severity.

Aims: To evaluate the effect of considerably high left ventricular filling pressure with mitral regurgitation on mitral annular velocity during early diastole.Subjects: Two hundred and forty-three patients who underwent cardiac catheterization for evaluation of chest pain.Methods: Mitral annular velocity during early diastole was measured by colour M-mode tissue Doppler imaging. Patients were divided into the following three groups according to the cardiac catheterization data. Group A (n=147): patients having left ventricular relaxation time constant τ<46 ms and left ventricular end-systolic volume index <38 ml m−2; group B (n=88): patients having τ≥46 ms and/or end-systolic volume index ≥38 ml m−2; group C (n=8): patients having mean pulmonary capillary wedge pressure ≥16 mmHg in addition to τ≥46 ms and end-systolic volume index ≥38 ml m−2.Results: Mitral annular velocity during early diastole was significantly less in group B (4·8±1·4 cm s−1) than in group A (7·7±1·9 cm s−1). However, there was no significant difference between groups A and C (8·3±0·8 cm s−1). A transmitral E/A >1·0 was observed in 12/147 patients of group A, 10/88 of group B, and 8/8 of group C. The incidence of ≥Sellers' grade II mitral regurgitation was higher in group C than the others.Conclusions: A paradoxically faster mitral annular velocity during early diastole is found in patients having left ventricular dysfunction with moderate to severe mitral regurgitation and considerably high left ventricular filling pressure. Attention should be paid to an interpretation of mitral annular velocity during early diastole regarding left ventricular early diastolic performance in patients having mitral regurgitation with an E/A >1·0 in their transmitral flow. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved. [ABSTRACT FROM AUTHOR]