Hidekatsu Fukuta

Correlation between Left Ventricular End-diastolic Pressure and Peak Left Atrial Wall Strain during Left Ventricular Systole

OBJECTIVE Left atrial (LA) reservoir function is determined by integration of LA relaxation and left ventricular (LV) systolic function, and LV diastolic dysfunction increases LA volume at end systole. This study investigates the effect of LV end-diastolic pressure on LA wall tension during LV systole. METHODS A total of 101 stable patients with sinus rhythm undergoing cardiac catheterization were studied. LA wall extension during LV systole was evaluated as LA wall strain in the longitudinal direction obtained using two-dimensional ultrasound speckle tracking imaging. LV end-diastolic pressure and LV end-systolic and end-diastolic volumes were obtained in cardiac catheterization, and LV ejection fraction was determined. RESULTS Peak LA wall strain during LV systole had a significant inverse correlation with LV end-diastolic pressure (r = - 0.76, P < .0001). This correlation was also significant in patients with preserved LV systolic function (LV ejection fraction > or =50%) (r = - 0.64, P < .0001). In patients with peak LA wall strain during LV systole of less than 30%, 89% had elevated LV end-diastolic pressure (> or =16 mm Hg). CONCLUSION Elevated LV end-diastolic pressure is associated with a decrease of peak LA wall strain in the longitudinal direction during LV systole. In patients with peak LA wall strain during LV systole of less than 30%, the majority had elevated LV end-diastolic pressure, while most patients with peak LA wall strain during LV systole 45% or higher had normal LV end-diastolic pressures. In patients whose LV ejection fraction is 50% or more, when peak LA wall strain during LV systole is between 30% and 44%, it is not possible to predict LV end-diastolic pressure from peak LA wall strain measures.

The cardiac cycle and the physiologic basis of left ventricular contraction, ejection, relaxation, and filling.

Heart failure is defined as the pathologic state in which the heart is unable to pump blood at a rate required by the metabolizing tissues or can do so only with an elevated filling pressure. Heart failure in adults most frequently results from the inability of the left ventricle to fill (diastolic performance) or eject (systolic performance) blood. The severity of heart failure and its prognosis are more closely related to the degree of diastolic filling abnormalities than the ejection fraction, which underscores the importance of understanding the mechanisms of diastolic abnormalities in heart failure.

Effects of drug and exercise intervention on functional capacity and quality of life in heart failure with preserved ejection fraction: A meta-analysis of randomized controlled trials:

Background Patients with heart failure with preserved ejection fraction (HFpEF) are often elderly and their primary chronic symptom is severe exercise intolerance that results in a reduced quality of life (QOL).Thus, improvement of exercise capacity and QOL presents an important clinical outcome in HFpEF patients. Although the effects of interventions such as cardiovascular drugs and exercise training on exercise capacity and QOL in HFpEF patients have been examined in a number of clinical trials, the results are inconsistent due in part to limited power with small sample sizes. We aimed to conduct a meta-analysis of the randomized controlled trial (RCT)s on the effect of drug or exercise intervention on exercise capacity and QOL in HFpEF patients. Method and results The search of electronic databases identified five RCTs on exercise (245 patients) and eight RCTs on cardiovascular drugs (1080 patients). The pooled analysis showed that exercise training improved peak exercise oxygen uptake (VO2) (weighted mean difference (WMD) 2.283, 95% confidence interval (CI)) (1.318–3.248) ml/min/kg), six-minute walk distance (6MWD) (30.275 m (4.315–56.234)), and Minnesota Living with Heart Failure Questionnaire (MLHFQ) total score (8.974 points (3.321–14.627)) compared with usual care. In contrast, drug intervention did not improve peak VO2 (WMD (95% CI), –0.393 (−1.005–0.220) ml/min/kg), 6MWD (−9.463 (−21.455–2.530) m), or MLHFQ total score (1.042 (−0.982–3.066) point) compared with placebo or no treatment. Conclusion Our meta-analysis indicates that exercise training may be a therapeutic option to improve functional capacity and QOL in HFpEF patients.

Loss of Fractal Heart Rate Dynamics in Depressive Hemodialysis Patients

Objective: To assess the relationship between depression, reduced heart rate (HR) variability, and altered HR dynamics among patients with end-stage renal disease who are receiving hemodialysis (HD) therapy. Methods: We analyzed the 24-hour electrocardiograms of 119 outpatients receiving chronic HD. HR variability was quantified with the standard deviation of normal-to-normal R-R intervals, the triangular index, and the powers of the high- (HF), low- (LF), very-low (VLF), and ultra-low frequency (ULF) components. Nonlinear HR dynamics was assessed with the short-term (α1) and long-term (α2) scaling exponents of the detrended fluctuation analysis and approximate entropy. The depression level was assessed using the Beck Depression Inventory, Second Edition (BDI-II). HR variability and dynamics measurements were compared by gender, diabetes, and depression with adjustment for age and serum albumin concentration. Results: Most indices of HR variability and dynamics were negatively correlated with age, serum albumin concentration, depression score, and were lower in women and patients with diabetes. The α2 was inversely associated with these variables. Depressed men had significantly lower HF, LF, VLF, and marginally lower ULF than nondepressed persons after adjustment for diabetes and other covariates; no difference in depression was observed in women. The α2 showed marginally significant difference in depression independent from gender and diabetes. Conclusions: Among the patients who received HD, depression is associated with reduced HR variability and loss of fractal HR dynamics. However, the influence of depression on HR variability may vary by gender and physiological backgrounds. Further prospective studies are necessary to confirm their association with poor prognosis. CHD = coronary heart disease; HR = heart rate; DFA = detrended fluctuation analysis; ApEn = approximate entropy; HD = hemodialysis; ESRD = end-stage renal disease; NKC = Nagoya Kidney Center; AMI = acute myocardial infarction; ECG = electrocardiography; PCR = protein catabolic rate; SDNN = standard deviation of normal-to-normal R-R intervals; HF = high-frequency band; LF = low-frequency band; VLF = very-low-frequency band; ULF = ultra-low-frequency band; SD = standard deviation; mNN = mean normal-to-normal R-R intervals; BDI = Beck Depression Inventory; DSM = Diagnostic and Statistical Manual of Mental Disorders; ANCOVA = analysis of covariance; GLM = general linear model.

Observational studies of statins in heart failure with preserved systolic function.

This article reviews the available evidence from observational studies concerning the effect of statin therapy in patients who have heart failure and a preserved ejection fraction (diastolic heart failure). Observational studies suggest that statin therapy is associated with lower mortality in patients who have diastolic heart failure. These results emphasize the need for a randomized study of the effect of statins in diastolic heart failure. Until the results of such studies are available, it is recommended to use statins in patients with diastolic heart failure who otherwise have an indication for statin therapy.

The effect of statins on mortality in heart failure with preserved ejection fraction: a meta-analysis of propensity score analyses

BACKGROUND Nearly half of patients with heart failure (HF) have preserved ejection fraction (EF) and the mortality and morbidity of patients with HF with preserved EF (HFpEF) are high. However, no pharmacological therapy has been shown to improve survival in HFpEF patients. Previous retrospective and prospective observational studies have examined the prognostic impact of hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) in patients with HFpEF. However, the results are inconsistent due to limited power with small sample sizes and/or lack of adjustment for known prognostic factors and differences in baseline characteristics between patients treated with and without statins. METHODS We aimed to conduct a meta-analysis of prospective observational studies examining the effect of statin therapy on mortality in HFpEF patients with the use of propensity score analysis. RESULTS A total of 4 studies with 5,536 patients (2,768 patients [50%] on statins; mean age, 65-77 years; male, 43-66%; coronary artery disease, 42-64%; hypertension, 61-82%; diabetes, 20-29%; follow-up duration, 12-36 months) were included in this meta-analysis. The pooled analysis showed that statin therapy was associated with reduced mortality (odds ratio [95% CI] = 0.690 [0.493-0.965], P=0.030). CONCLUSION Our meta-analysis suggests the potential mortality benefit of statins in HFpEF. Further prospective observational studies and randomized controlled trials should be planned to confirm our observed potential survival benefit of statins in HFpEF.

Circadian rhythm of atrioventricular conduction predicts long-term survival in patients with chronic atrial fibrillation

The R–R interval of the electrocardiogram during atrial fibrillation (AF) appears absolutely irregular. However, the Poincaré plot of the R–R interval reveals a sector shape of distribution that is unique to AF. Furthermore, the height of lower envelope (LE1.0) of the distribution and the degree of scatter above the envelope (scattering index) may reflect the refractoriness and concealment of atrioventricular (AV) conduction, respectively. We previously observed that both the LE1.0 and scattering index show clear circadian rhythms in patients with chronic AF and that the rhythms are blunted in those with congestive heart failure and chronic AF. In the present study, we examined if the blunted circadian rhythm of the AV conduction has prognostic value in patients with chronic AF. We studied a retrospective cohort of 120 patients who underwent 24h Holter monitoring at baseline. During an observation period of 33±16 mon, there were 25 deaths (21%) including 13 cardiac and 8 stroke deaths. All patients showed significant circadian rhythms in both LE1.0 and scattering index with acrophases occurring at night; however, patients dying subsequently from cardiac causes, but not those from fatal stroke were blunted in the circadian rhythms (the amplitudes were <55% of those in surviving patients). Furthermore, the reduced circadian amplitude of scattering index was an increased risk for cardiac death even after adjustment of coexisting cardiovascular risks [adjusted relative risk (95% confidence interval) per 1-SD decrement, 4.24 (1.54–11.6)]. When patients were divided by the circadian amplitude of the scattering index of 36.5 msec (mean minus 1-SD), the 5yr cardiac mortality below and above the cutoff was 57 and 6%, respectively (log-rank test, p<0.001). We conclude that the blunted circadian rhythm of AV conduction is an independent risk for cardiac death in patients with chronic AF.

Usefulness of Plasma Brain Natriuretic Peptide Measurement and Tissue Doppler Imaging in Identifying Isolated Left Ventricular Diastolic Dysfunction Without Heart Failure

Left ventricular (LV) diastolic dysfunction carries a substantial risk for the subsequent development of heart failure and reduced survival, even when it is asymptomatic. Plasma brain natriuretic peptide (BNP) level and tissue Doppler imaging indexes provide powerful incremental assessment of LV diastolic function. Accordingly, the aim of this study was to clarify whether these methodologies could identify LV diastolic dysfunction without heart failure in 280 patients with preserved LV ejection fractions (> or =50%) who underwent echocardiography and cardiac catheterization for the evaluation of coronary artery disease. Patients were classified into 2 groups, those with diastolic dysfunction (tau > or =48 ms; n = 91) and those with normal diastolic function (tau <48 ms; n = 189). Plasma BNP > or =22.4 pg/ml, an unexpectedly low value, had sensitivity of 74.7% and specificity of 60.8% for identifying isolated LV diastolic dysfunction; the combined use of BNP > or =22.4 pg/mL and mitral annular velocity during early diastole <7.4 cm/s had relatively low sensitivity of 44.0% but high specificity of 86.8%. In conclusion, using plasma BNP level and with the combination of BNP level and mitral annular velocity during early diastole, invasively proved isolated LV diastolic dysfunction without heart failure could be identified in patients with coronary artery disease.

Reduced renal function is associated with combined increases in ventricular-systolic stiffness and arterial load in patients undergoing cardiac catheterization for coronary artery disease

Although mildly reduced renal function is associated with increased risk for heart failure in patients with coronary artery disease (CAD), mechanisms underlying the association remain unclear. We tested the hypothesis that abnormal ventricular-arterial interaction may occur in mildly reduced renal function. We examined the relationships of the estimated glomerular filtration rate (eGFR) with various indices reflecting ventricular–arterial coupling [effective arterial elastance (the ratio of left ventricular (LV) end-systolic pressure to stroke volume, Ea], LV end-systolic elastance (the ratio of LV end-systolic pressure to end-systolic volume, Ees), and the total arterial compliance (the ratio of stroke volume to aortic pulse pressure)] and those of LV systolic and diastolic function [peak systolic and diastolic mitral annular velocities (S′ and E′) and the ratio of peak early diastolic mitral inflow to annular velocity (E/E′)] in 320 consecutive patients who underwent cardiac catheterization for CAD and had normal (≥0.50) ejection fractions (EF). As eGFR decreased, Ea and Ees increased and total arterial compliance and E′ decreased. eGFR did not correlate with Ea/Ees, S′, or E/E′. After adjusting for potential confounders, the findings were generally similar, but the correlation of eGFR with E′ did not remain significant. In conclusion, reduced renal function may be associated with combined increases in ventricular-systolic stiffness and arterial load in known or suspected CAD patients with normal EF.

Relation of Plasma Levels of Adiponectin to Left Ventricular Diastolic Dysfunction in Patients Undergoing Cardiac Catheterization for Coronary Artery Disease

In the present study, we hypothesized that hypoadiponectinemia and hyperleptinemia might be associated with left ventricular (LV) diastolic dysfunction. To test the hypothesis, we examined the relation of the plasma levels of adiponectin and leptin with the indexes of LV diastolic and systolic function (relaxation time constant, end-diastolic pressure, and ejection fraction) in 193 consecutive patients undergoing cardiac catheterization for coronary artery disease (age 69 ± 9 years, 74% men; ejection fraction 68.4 ± 9.9%). Regardless of gender, the adiponectin levels correlated negatively with the relaxation time constant and end-diastolic pressure, and the correlations remained significant after adjustment for potential confounders, including age, body mass index, heart rate, blood pressure, and coronary artery disease severity. Adiponectin levels did not significantly correlate with the ejection fraction in either men or women. The leptin levels did not significantly correlate with the indexes of LV diastolic or systolic function in either men or women. In conclusion, we found that decreased adiponectin levels were associated with LV diastolic dysfunction in patients with known or suspected coronary artery disease.