Kei Mizukoshi

Relationship between left ventricular ejection fraction and mitral annular displacement derived by speckle tracking echocardiography in patients with different heart diseases.

BACKGROUND Speckle tracking echocardiography (STE)-derived mitral annular displacement (MAD) utilizes the speckle tracking technique to measure strain vectors, which provides accurate estimates of left ventricular ejection fraction (LVEF). Here, we investigated a link between STE-derived MAD and LVEF in patients with different heart diseases and evaluated its clinical usefulness. METHODS This study included 266 outpatients and 84 controls. Of the study patients, 52 patients had ischemic heart disease (IHD), 37 patients had dilated cardiomyopathy (DCM), 34 patients had hypertrophic cardiomyopathy (HCM), 74 patients had valvular heart disease (VHD), and 69 patients had hypertensive heart disease (HHD). STE continuously tracked annular motion throughout the cardiac cycle in the apical 4- and 2-chamber views. RESULTS In all participants, the curvilinear relationship was found between STE-derived MAD and LVEF (R(2)=0.642). The strong correlation between STE-derived MAD and LVEF was also found in the patients with IHD (R(2)=0.733, p=0.001) and in those with DCM (R(2)=0.614, p=0.008). However, such a correlation was not found in the patients with HCM, VHD, or HHD. CONCLUSION The specificity in the correlation between STE-derived MAD and LVEF was found in patients with each heart disease, which should be taken into account when assessing these parameters.

Simple exercise echocardiography using a Master's two-step test for early detection of pulmonary arterial hypertension

BACKGROUND Early detection of pulmonary arterial hypertension (PAH) is indispensable, although, echocardiography at rest alone does not provide sufficient evidence for it. Here, this study aimed to investigate the usefulness of simple exercise echocardiography using a Masters two-step test for detecting early PAH. METHODS This study included 52 connective tissue disease patients who had mild symptoms in World Health Organization functional classification 2, suspected as having early PAH, and underwent exercise echocardiography and right heart catheterization. Echocardiography was performed before and after the Masters two-step exercise test; the study patients were classified into the non-PAH (mean pulmonary arterial pressure <25 mmHg, n=37) or PAH (mean pulmonary arterial pressure ≥25 mmHg, n=15) groups. RESULTS Rest systolic pulmonary artery pressure estimated using echocardiography did not significantly differ between the two groups; however, a significant difference in post-exercise systolic pulmonary artery pressure was found (non-PAH, 58.8±10.8 mmHg; PAH, 80.2±14.3 mmHg, p<0.0001). The multiple logistic regression analysis indicated post-exercise systolic pulmonary artery pressure as an independent predictor of PAH (p=0.013). The area under the curve by post-exercise systolic pulmonary artery pressure was 0.91 for PAH. Post-exercise systolic pulmonary artery pressure ≥69.6 mmHg predicted PAH with the sensitivity of 93% and the specificity of 90%. CONCLUSIONS Simple exercise echocardiography using the Masters two-step test could detect PAH in mildly symptomatic connective tissue disease patients. The usefulness of this method should be verified for the early detection of PAH.

Normal Values of Left Ventricular Mass Index Assessed by Transthoracic Three-Dimensional Echocardiography

BACKGROUND Pathologic left ventricular (LV) hypertrophy is closely coupled with adverse cardiovascular events. However, normal values of LV mass determined by three-dimensional echocardiography (3DE) have not been established in a large number of healthy subjects over a wide age range. The aims of this study were to (1) validate the accuracy of 3DE for LV mass measurements against cardiac magnetic resonance (CMR), (2) establish the normal range of LV mass index in healthy subjects, and (3) investigate the effects of age, gender, and ethnic diversity on LV mass index. METHODS In protocol 1, both transthoracic 3DE and CMR were performed on the same day in 57 patients who underwent clinically indicated CMR examinations. In protocol 2, full-volume data sets were acquired with 3DE in 390 healthy subjects. The LV endocardial and epicardial borders were semiautomatically determined at end-diastole using three-dimensional echocardiographic software. LV mass was calculated as (LV epicardial volume--LV endocardial volume) × 1.05. RESULTS Excellent correlation was observed between three-dimensional echocardiographic and CMR measurements of LV mass (r = 0.96). Bland-Altman analysis revealed bias of -4.8 g (-3.9% of the mean), with 95% limits of agreement of ± 27.7 g. Normal values of LV mass indexed to body surface area were found to be 70 ± 9 g/m(2) in men and 61 ± 8 g/m(2) in women. Significant age and gender dependence, but no racial dependence, was observed for LV mass index. CONCLUSIONS Three-dimensional echocardiography is an accurate method for measuring LV mass. Age and gender dependence, but no ethnic dependence, of LV mass index was observed in Japanese and American populations. The reported normal reference values of 3DE-determined LV mass index according to age and gender could potentially be useful for diagnosing LV hypertrophy with excellent accuracy.

Influence of exercise-induced pulmonary hypertension on exercise capacity in asymptomatic degenerative mitral regurgitation.

BACKGROUND Exercise capacity is helpful in the management of patients with mitral regurgitation (MR). However, the determinants of exercise capacity reduction in MR have remained unclear. This study was designed to objectively assess exercise capacity, identify the echocardiographic predictors of exercise capacity, and investigate its impact on development of symptoms in asymptomatic degenerative MR. METHODS A total of 49 consecutive asymptomatic patients (age, 58.9±13.1 years; 82% males) with at least moderate degenerative MR (effective regurgitant orifice area=0.40±0.14cm(2); regurgitant volume=60.9±19.6mL) underwent the symptom-limited cardiopulmonary exercise testing for assessing exercise capacity (peak oxygen uptake, peak V˙O2; the minute ventilation/carbon dioxide production, V˙E/V˙CO2 slope). All patients also underwent exercise stress echocardiography for detecting exercise-induced pulmonary hypertension (EIPH) defined by systolic pulmonary arterial pressure (SPAP) ≥60mmHg. RESULTS The mean peak V˙O2 was 22.6±5.1mL/kg/min (86.7±14.1% of age, gender-predicted); peak V˙O2 widely varied (48-121% of predicted), and was markedly reduced (<80.4% of predicted) in 24% of the study patients. The patients with EIPH had lower 2-year symptom-free survival than those without EIPH (p=0.003). The multivariable analysis demonstrated that EIPH was an independent echocardiographic determinant of peak V˙O2 (p=0.001) and V˙E/V˙CO2 slope (p=0.021). Furthermore, the area under curve of age- and gender-adjusted exercise SPAP was 0.88 (95% confidence interval: 0.78-0.97) for reduced exercise capacity. CONCLUSIONS In asymptomatic moderate to severe degenerative MR, EIPH was independently associated with exercise capacity and predicted the occurrence of symptoms. Exercise stress echocardiography is an important tool in managing patients with asymptomatic degenerative MR.

Influence of Pulmonary Vascular Reserve on Exercise‐Induced Pulmonary Hypertension in Patients with Systemic Sclerosis

Exercise‐induced pulmonary hypertension (PH) is considered as an early preclinical functional phase of resting PH in systemic sclerosis (SSc). In this study, we investigated the prevalence of exercise‐induced PH in patients with SSc and evaluated the influence of pulmonary vascular reserve on exercise‐induced PH.

Value of anatomical aortic valve area using real-time three-dimensional transoesophageal echocardiography in patients with aortic stenosis: a comparison between tricuspid and bicuspid aortic valves.

AIMS Accurate assessment of disease severity is critical for appropriate treatment of patients with aortic stenosis (AS). This study investigated the influence of aortic-valve morphology on the determination of anatomical aortic-valve area (AVA) in patients with AS. METHODS AND RESULTS This prospective study included 126 patients with AS who underwent transoesophageal echocardiography (TEE). Aortic-valve area was measured using (i) planimetric two-dimensional (2D) TEE, (ii) volumetric three-dimensional (3D) TEE, and (iii) the continuity equation (CE) obtained with transthoracic echocardiography. Of these, 20 patients also underwent contrast-enhanced multidetector computed tomography (MDCT). Aortic-valve area was measured from multiplanar reconstruction of the MDCT images. Of the 126 patients, 20 (15.9%) were diagnosed with bicuspid AS and 106 were diagnosed with tricuspid AS. There was an excellent correlation between AVAADCT and AVA3DTEE (r = 0.83, P < 0.001) and a somewhat lower correlation between AVAADCT and AVA2DTEE (r = 0.63, P = 0.006). In the tricuspid AS group, both AVA2DTEE and AVA3DTEE significantly correlated with AVACE (r = 0.63, mean difference 0.13 ± 0.24 cm(2), and r = 0.83, mean difference 0.03 ± 0.12 cm(2), respectively, both P < 0.001). In contrast, in the bicuspid AS group, AVA3DTEE significantly correlated with AVACE (r = 0.83, mean difference 0.10 ± 0.18 cm(2), P < 0.001), whereas AVA2DTEE did not (r = 0.42, mean difference 0.48 ± 0.32 cm(2), P = 0.066). CONCLUSION Aortic-valve morphology influenced the assessment of anatomical AVA in patients with AS, and 3D TEE is useful for assessing anatomical AVA regardless of aortic-valve morphology.

Predictors of Exercise-Induced Pulmonary Hypertension in Patients with Asymptomatic Degenerative Mitral Regurgitation: Mechanistic Insights from 2D Speckle-Tracking Echocardiography

Presence of exercise-induced pulmonary hypertension (EIPH) in asymptomatic degenerative mitral regurgitation (DMR) determines prognosis. This study aimed to elucidate the mechanism and predictors of EIPH in asymptomatic DMR. Ninety-one consecutive asymptomatic patients with DMR who underwent exercise stress echocardiography were prospectively included. We obtained various conventional echocardiographic parameters at rest and during peak exercise, as well as left atrial (LA) function at rest using 2-dimensional speckle-tracking analysis. The 25 patients (33.3%) with EIPH were significantly older and had a greater ratio of mitral peak velocity of early filling to early diastolic mitral annular velocity during peak exercise than those without EIPH. LA strain (LAS)-s and LAS-e, indices of LA reservoir and conduit function, respectively, were significantly lower in those with EIPH than in those without EIPH. Multivariate analysis indicated that LAS-s was the only resting echocardiographic parameter that independently predicted EIPH, with a cut-off value of 26.9%. Furthermore, Kaplan-Meier curve analysis showed that symptom-free survival was markedly lower among those with reduced LAS-s. In conclusion, decreased LA reservoir function contributes to EIPH, and LAS-s at rest is a useful indicator for predicting EIPH in asymptomatic patients with DMR.

Hyperventilation and cold-pressor stress echocardiography combined with automated functional imaging non-invasively detected vasospastic angina

A 47-year-old male presented with chest discomfort while sleeping. The patient was suspected of having vasospastic angina (VSA) and underwent hyperventilation and cold-pressor stress echocardiography. No chest pain, ECG changes or decreased wall motion was found. However, automated function imaging (AFI) showed decreased peak systolic strain at the apex and postsystolic shortening at both the apex and inferior wall, which was not found before the test. The provocation test revealed 99% stenosis in the right coronary artery #2 at a dose of 50 μg acetylcholine and 90% stenosis in the left coronary artery #8 at a dose of 100 μg. The patient was thus diagnosed as having VSA. The present case demonstrates the usefulness of AFI combined with hyperventilation and cold-pressor stress echocardiography as a screening examination for VSA.