Manabu Takai

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.

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.

Impaired β-cell function attenuates training effects by reducing the increase in heart rate reserve in patients with myocardial infarction

BACKGROUND Insulin resistance (IR) is characterized as a metabolic disorder syndrome that is upstream of hypertension, dyslipidemia, and diabetes mellitus (DM). This study investigated exercise training effects on the exercise tolerance and heart rate dynamics in patients with IR or pancreatic β-cell dysfunction. METHODS Seventy patients (mean age, 60.1 years) with myocardial infarction (MI) participating in a phase II cardiac rehabilitation program were studied. Patients diagnosed with DM were excluded. Homeostasis model-assessment indices were used to divide patients into three groups - A: IR; B: normal; and C: β-cell dysfunction. A cardiopulmonary exercise test (CPX) was performed and peak oxygen uptake (V˙O2) was measured. After baseline testing, subjects participated in a supervised, combined aerobic and resistance exercise program. RESULTS Peak V˙O2 at baseline was comparable among the three groups, and it improved after training in all groups (p<0.05). However, both the increase and percentage increase in peak V˙O2 were smaller in Group C than in Group A (p<0.05). Heart rate (HR) reserve (peak HR-rest HR), and HR recovery immediately 1min after exercise during CPX were calculated in 45 patients who were not taking negative chronotropic agents. Group C alone did not show any significant increase in HR reserve. HR reserve at both baseline and after training had significant positive correlations with peak V˙O2. HR recovery was 1.9 beats/min lower in group C than group A, but this was not significant. HR recovery in group C did not increase after cardiac rehabilitation. CONCLUSION Impaired HR reserve increase after training in patients with pancreatic β-cell dysfunction attenuates exercise training effects on functional capacity. Comprehensive treatment including vigorous exercise training will be needed in such prediabetic patients.

Novel Use of GuideLiner with a Low-Profile Balloon for the Retrieval of Disrupted Balloon Catheter

We report a case of successful percutaneous retrieval of an unexpectedly disrupted balloon catheter using GuideLiner and a low-profile balloon. The procedure and the mechanism of this novel technique were described in detail with ex-vivo testing. This case demonstrated the utility of the combination of GuideLiner and low-profile balloon as a bail-out for intravascular foreign body.

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.

A NEW SUTURE MATERIAL IN THE FIELD OF CARDIAC DEVICE IMPLANTATION

Background: The cardiac device implantation is a minor surgical procedure. One of the problems is a suture knot sticking out 1-3 months after operation. A unidirectional barbed suture (V-Loc; Covidien, Mansfield, MA) is a suture with barbs, which enables running sutures without knots. The

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.