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13
result(s) for
"Takemoto, Kazushi"
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Impact of left ventricular ejection fraction and preoperative hemoglobin level on perioperative adverse cardiovascular events in noncardiac surgery
2021
The prediction of a perioperative adverse cardiovascular event (PACE) is an important clinical issue in the medical management of patients undergoing noncardiac surgery. Although several predictors have been reported, simpler and more practical predictors of PACE have been needed. The aim of this study was to investigate the predictors of PACE in noncardiac surgery. We retrospectively analyzed 723 patients who were scheduled for elective noncardiac surgery and underwent preoperative examinations including 12-lead electrocardiography, transthoracic echocardiography, and blood test. PACE was defined as cardiac death, non-fatal myocardial infarction, unstable angina, congestive heart failure, arrhythmia attack that needs emergency treatment (rapid atrial fibrillation, ventricular tachycardia, and bradycardia), acute pulmonary embolism, asystole, pulseless electrical activity, or stroke during 30 days after surgery. PACE occurred in 54 (7.5%) of 723 patients. High-risk operation (11% vs. 3%,
p
= 0.003) was more often seen, left ventricular ejection fraction (LVEF) (55 ± 8% vs. 60 ± 7%,
p
= 0.001) and preoperative hemoglobin level (11.8 ± 2.2 g/dl vs. 12.7 ± 2.0 g/dl,
p
= 0.001) were lower in patients with PACE compared to those without PACE. By multivariate logistic regression analysis, high-risk operation (odds ratio (OR): 7.05, 95% confidence interval (CI) 2.16–23.00,
p
= 0.001), LVEF (OR 1.06, every 1% decrement, 95% CI 1.03–1.09,
p
= 0.001), and preoperative hemoglobin level (OR 1.22, every 1 g/dl decrement, 95% CI 1.07–1.39,
p
= 0.003) were identified as independent predictors of PACE. Receiver operating characteristic analysis demonstrated that LVEF of 58% (sensitivity = 80%, specificity = 61%, area under the curve (AUC) = 0.723) and preoperative hemoglobin level of 12.2 g/dl (sensitivity = 63%, specificity = 64%, AUC = 0.644) were optimal cut-off values for predicting PACE. High-risk operation, reduced LVEF, and reduced preoperative hemoglobin level were independently associated with PACE in patients undergoing noncardiac surgery.
Journal Article
Feasibility of tissue-tracking mitral annular displacement in single four-chamber view as a simple index of left ventricular longitudinal deformation
by
Fujita, Suwako
,
Hozumi, Takeshi
,
Kubo, Takashi
in
Cardiomyopathy
,
Ejection fraction
,
Patients
2022
BackgroundLeft ventricular global longitudinal strain (LVGLS) has prognostic value for adverse cardiac events. Application of speckle-tracking technology to mitral annulus provides easy assessment of tissue-tracking mitral annular displacement (TMAD) in apical four-chamber view. The study aimed to examine whether TMAD can be used as a simple index of LV longitudinal deformation in patients with and without preserved ejection fraction (EF).MethodsThe study population consisted of 95 consecutive subjects. GLS was assessed from three apical views. TMAD was evaluated as the base-to-apex displacement of septal (TMADsep), lateral (TMADlat), and mid-point of annular line (TMADmid) in apical 4-chamber view. The percentage of TMADmid to LV length from the mid-point of mitral annuls to the apex at end-diastole (%TMADmid) was calculated. We compared each TMAD parameter with GLS by linear regression analysis, and analyzed each TMAD parameter by receiver operating characteristic (ROC) curve to detect impaired LV longitudinal deformation (|GLS|< 15.0%).ResultsThere were good correlations between each TMAD parameter and GLS (TMADsep: r2 = 0.59, p < 0.01. TMADlat: r2 = 0.65, p < 0.01. TMADmid: r2 = 0.68, p < 0.01. %TMADmid: r2 = 0.75, p < 0.01). According to ROC curve, %TMADmid < 10.5% was the best cut-off value in determining impaired LV longitudinal deformation (|GLS|≤ 15.0%) with a sensitivity of 95% and a specificity of 93%. The area under the curve (AUC) of %TMADmid was 0.98 (95% confidence intervals (CI) 0.93–0.99).ConclusionsTMAD using speckle-tracking echocardiography quickly estimated from single apical four-chamber view can be used as a simple index for detection of impaired LV longitudinal deformation in patients with and without preserved EF.
Journal Article
Noninvasive estimation of impaired left ventricular untwisting velocity by peak early diastolic intra-ventricular pressure gradients using vector flow mapping
by
Fujita, Suwako
,
Kubo, Takashi
,
Akasaka, Takashi
in
Catheters
,
Patients
,
Pressure distribution
2021
BackgroundIntroduction of vector flow mapping (VFM) based on the combination of color Doppler and speckle-tracking echocardiography provides noninvasive assessment of early diastolic intra-ventricular pressure gradient (ED-IVPG). The purpose of this study was to evaluate the value of peak ED-IVPG measurement just after aortic valve closure using VFM for noninvasive estimation of impaired LV untwisting velocity as the index of LV relaxation in the clinical setting.Methods and resultsThe study included 65 consecutive patients in whom echocardiography was performed for the assessment of LV function. We assessed peak ED-IVPG between LV apex and base by VFM analysis software. We also measured peak LV untwisting velocity and LV twisting by speckle-tracking strain analysis. Peak ED-IVPG was successfully and quickly assessed in all the study patients. Peak ED-IVPG was significantly reduced in patients with impaired peak LV untwisting velocity (< 70 degrees/s) compared with patients without impaired peak LV untwisting velocity. The receiver operating characteristic analysis showed the best cut-off value of peak ED-IVPG for determining impaired peak LV untwisting velocity was 0.40 mmHg (sensitivity 81%, specificity 74%, and area under the curve 0.81). There was a well correlation between peak ED-IVPG and peak LV untwisting velocity (r = 0.64, p < 0.0001).ConclusionsThe present results suggest that peak ED-IVPG just after aortic valve closure measured by VFM may be used as noninvasive index for estimation of impaired LV untwisting velocity in the clinical setting.
Journal Article
Implications of multiple late gadolinium enhancement lesions on the frequency of left ventricular reverse remodeling and prognosis in patients with non‐ischemic cardiomyopathy
2021
Background
Non-ischemic cardiomyopathy (NICM) is a heterogeneous disease, and its prognosis varies. Although late gadolinium enhancement (LGE)-cardiovascular magnetic resonance (CMR) demonstrates a linear pattern in the mid-wall of the septum or multiple LGE lesions in patients with NICM, the therapeutic response and prognosis of multiple LGE lesions have not been elucidated. This study aimed to investigate the frequency of left ventricular (LV) reverse remodeling (LVRR) and prognosis in patients with NICM who have multiple LGE lesions.
Methods
This single-center retrospective study included 101 consecutive patients with NICM who were divided into 3 groups according to LGE-CMR results: patients without LGE (no LGE group = 48 patients), patients with a typical mid-wall LGE pattern (n = 29 patients), and patients with multiple LGE lesions (n = 24 patients). LVRR was defined as an increase in LV ejection fraction (LVEF) ≥ 10 % and a final value of LVEF > 35 %, which was accompanied by a decrease in LV end-systolic volume ≥ 15 % at 12-month follow-up using echocardiography. The frequency of composite cardiac events, defined as sudden cardiac death (SCD), aborted SCD (non-fatal ventricular fibrillation, sustained ventricular tachycardia, or adequate implantable cardioverter-defibrillator therapies), and heart failure death or hospitalization for worsening heart failure, were summarized and compared between the groups.
Results
Among the 3 groups, the frequency of LVRR was significantly lower in the multiple lesions group than in the no LGE and mid-wall groups (no LGE vs. mid-wall vs. multiple lesions: 49 % vs. 52 % vs. 19 %, p = 0.03). There were 24 composite cardiac events among the patients: 2 in patients without LGE (hospitalization for worsening heart failure; 2), 7 in patients of the mid-wall group (SCD; 1, aborted SCD; 1 and hospitalization for worsening heart failure; 5), and 15 in patients of the multiple lesions group (SCD; 1, aborted SCD; 8 and hospitalization for worsening heart failure; 6). The multiple LGE lesions was an independent predictor of composite cardiac events (hazard ratio: 11.40 [95 % confidence intervals: 1.49−92.01], p = 0.020).
Conclusions
Patients with multiple LGE lesions have a higher risk of cardiac events and poorer LVRR. The LGE pattern may be useful for an improved risk stratification in patients with NICM.
Journal Article
Association of left pulmonary vein trunk and subclinical atrial fibrillation in patients with cardiac implantable electronic device
2024
The relationship between subclinical atrial fibrillation (SCAF) and left pulmonary vein anatomy is unknown. This study sought to investigate whether left pulmonary vein trunk predict the development of SCAF in patients with cardiac implantable electronic device (CIED). We also examined the relationship between the duration of SCAF and left pulmonary vein trunk. We retrospectively enrolled 162 patients who underwent implantation of dual-chamber CIEDs and follow-up by remote monitoring system. Computed tomography was used to measure the length of the left pulmonary vein. During median follow up of 2.7 years, the episodes of > 6 min and > 24 h SCAF were observed in 61 (37.7%) and 24 (14.8%) patients, respectively. The diagnosis of sinus node disease (HR: 3.66 [2.06–6.52],
P
< 0.01 and HR: 2.68 [1.09–6.62],
P
= 0.04) and left atrial diameter (HR: 1.04 [1.00–1.07],
P
= 0.04 and HR: 1.05 [1.00–1.10],
P
= 0.04) were independent predictors for > 6 min and > 24 h SCAF, respectively. Length of the left pulmonary vein trunk was an independent predictor for > 6 min SCAF (HR: 1.06 [1.02–1.10],
P
< 0.01), but not for > 24 h SCAF (
P
= 0.06). Sinus node disease, size of the left atrium and length of the left pulmonary vein trunk were related to SCAF. The left pulmonary vein trunk might especially contribute as a trigger rather than as a driver of development of atrial fibrillation.
Journal Article
Multi-Dimensional Wireless Tomography Using Tensor-Based Compressed Sensing
by
Hara, Shinsuke
,
Ono, Fumie
,
Yokota, Kengo
in
Algorithms
,
Anechoic chambers
,
Communications Engineering
2017
Wireless tomography is a technique for inferring a physical environment within a monitored region by analyzing RF signals traversed across the region. In this paper, we consider wireless tomography in a two and higher dimensionally structured monitored region, and propose a multi-dimensional wireless tomography scheme based on compressed sensing to estimate a spatial distribution of shadowing loss in the monitored region. In order to estimate the spatial distribution, we consider two compressed sensing frameworks:
vector-based compressed sensing
and
tensor-based compressed sensing
. When the shadowing loss has a high spatial correlation in the monitored region, the spatial distribution has a sparsity in its frequency domain. Existing wireless tomography schemes are based on the vector-based compressed sensing and estimates the distribution by utilizing the sparsity. On the other hand, the proposed scheme is based on the tensor-based compressed sensing, which estimates the distribution by utilizing its low-rank property. With simulation experiments, we reveal that the tensor-based compressed sensing has a potential for highly accurate estimation as compared with the vector-based compressed sensing. In order to show the possibility of the wireless tomography schemes in practical environments, we also show an experimental result in an anechoic chamber.
Journal Article
Effect of Erythropoietin Administration on Myocardial Viability and Coronary Microvascular Dysfunction in Anterior Acute Myocardial Infarction: Randomized Controlled Trial in the Japanese Population
2018
IntroductionCardioprotective effects of erythropoietin (EPO) on infarcted myocardium in acute myocardial infarction (AMI) patients have been inconclusive. This study aimed to assess the effect of EPO administration on coronary microvascular dysfunction (CMD) and myocardial viability in anterior AMI. We also evaluated the serial changes in CMD and cardiac remodeling in these patients.MethodsPatients with a successful percutaneous coronary intervention (PCI) for the first anterior AMI were randomly assigned to two groups (EPO and control groups), and given single-dose intravenous administration of recombinant human EPO (12,000 IU) or saline after PCI. Delayed-enhanced cardiac magnetic resonance imaging was performed at 1 week after AMI to assess the average of transmural extent of infarction and infarct size. Coronary flow velocity reserve (CFVR) of the left anterior descending coronary artery was measured by Doppler echocardiography at 1 week, 1 month, and 8 months after AMI. All patients underwent clinical follow-up for the assessment of cardiac remodeling.ResultsSixty-one patients (EPO 32, control 29) were eligible for analysis. EPO group (2.4 ± 1.2) had a tendency of smaller transmural extent of infarction than that of control group (2.9 ± 1.1; p = 0.063). CFVR-8 months improved significantly in EPO group (2.9 ± 0.6) compared to control group (2.6 ± 0.5; p = 0.04). Left atrial (LA) volume − 8 months was significantly lower in EPO group (47 ± 11) than those of control group (65 ± 20; p = 0.004).ConclusionsA single medium dose of EPO could have a favorable effect on CMD and LA remodeling in the chronic phase of anterior AMI.Trial RegistrationThe institutional ethics committee of Wakayama Medical University, identifier, 1125.
Journal Article
Prognostic value of tissue-tracking mitral annular displacement by speckle-tracking echocardiography in asymptomatic aortic stenosis patients with preserved left ventricular ejection fraction
2021
BackgroundTissue-tracking mitral annular displacement (TMAD) by speckle-tracking echocardiography provides rapid and simple assessment of left ventricular (LV) longitudinal deformation. The purpose of this study was to evaluate the value of TMAD for the assessment of LV longitudinal deformation in patients with severe AS and preserved LV ejection fraction (LVEF).MethodsWe studied 44 patients with severe AS preserved and LVEF in whom TMAD was assessed. Using TMAD analysis software, the base-to-apex displacement of automatically defined mid-point of mitral annular line in four-chamber view was quickly assessed, and the percentage of its displacement to LV length at end-diastole (%TMAD) was calculated. We investigated the association between %TMAD and the cardiac events including appearance of symptom (dyspnea on exertion and hospitalization due to heart failure), decreased LVEF (< 50%), and cardiac death.ResultsDuring follow-up, the cardiac events developed in 16 (36%) of 44 patients. %TMAD was significantly impaired in patients with the cardiac events compared with those without the cardiac events (9.6 ± 1.9 vs 12.1 ± 2.6, p = 0.002). The cardiac events were predicted by %TMAD (HR 0.68, 95% CI 0.54–0.85; p = 0.0012).ConclusionsThe present study suggests that TMAD easily and rapidly estimated by speckle-tracking echocardiography may be used as a simple method to predict occurrence of the cardiac events in asymptomatic severe AS patients with preserved LVEF.
Journal Article
Left ventricular apical aneurysm due to unrecognized sarcoidosis
2010
A 47-year-old woman was hospitalized for syncope. An electrocardiogram showed complete right bundle branch block and T-wave inversion in leads III, aVF, and V2–4. Cardiac catheterization was performed since the echocardiogram demonstrated the existence of a left ventricular apical aneurysm and apical thrombus. Coronary angiography revealed normal coronary arteries. An endomyocardial biopsied specimen from the right ventricular apical wall demonstrated typical noncaseating granulomas with giant cells. There was no evidence suggesting the involvement of other systemic organs. The patient was diagnosed as having cardiac sarcoidosis. Cardiac sarcoidosis should be considered within a spectrum of diseases that cause left ventricular apical aneurysm.
Journal Article
Multi-Dimensional Wireless Tomography with Tensor-Based Compressed Sensing
by
Hara, Shinsuke
,
Ono, Fumie
,
Matsuda, Takahiro
in
Compressed sensing
,
Environmental monitoring
,
Mathematical analysis
2014
Wireless tomography is a technique for inferring a physical environment within a monitored region by analyzing RF signals traversed across the region. In this paper, we consider wireless tomography in a two and higher dimensionally structured monitored region, and propose a multi-dimensional wireless tomography scheme based on compressed sensing to estimate a spatial distribution of shadowing loss in the monitored region. In order to estimate the spatial distribution, we consider two compressed sensing frameworks: vector-based compressed sensing and tensor-based compressed sensing. When the shadowing loss has a high spatial correlation in the monitored region, the spatial distribution has a sparsity in its frequency domain. Existing wireless tomography schemes are based on the vector-based compressed sensing and estimates the distribution by utilizing the sparsity. On the other hand, the proposed scheme is based on the tensor-based compressed sensing, which estimates the distribution by utilizing its low-rank property. We reveal that the tensor-based compressed sensing has a potential for highly accurate estimation as compared with the vector-based compressed sensing.