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Hideaki Kanzaki

Bio: Hideaki Kanzaki is an academic researcher from University of Pittsburgh. The author has contributed to research in topics: Heart failure & Cardiac resynchronization therapy. The author has an hindex of 27, co-authored 183 publications receiving 2830 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the authors tested the hypothesis that an immediate reduction in mitral regurgitation after cardiac resynchronization therapy (CRT) results from improved coordinated timing of the papillary muscle insertion sites, using the novel approach of mechanical activation strain mapping.

351 citations

Journal ArticleDOI
TL;DR: It is demonstrated that differences in baseline time-to-speak velocities of opposing ventricular walls by TSI were greater in 15 patients, with an acute hemodynamic improvement, suggesting that acute response underestimates long-term effects.
Abstract: Echocardiographic tissue synchronization imaging (TSI) consists of color-coding time-to-peak tissue Doppler velocities. This study of 29 patients who underwent cardiac resynchronization therapy (CRT) demonstrated that differences in baseline time-to-speak velocities of opposing ventricular walls by TSI were greater in 15 patients, with an acute hemodynamic improvement. A >/=65 ms delay from the anterior septum to the posterior wall using the apical long-axis view had 87% sensitivity and 100% specificity for predicting an acute response. Although a subgroup without acute improvement had later decreases in end-systolic volume, suggesting that acute response underestimates long-term effects, TSI has potential to assist in guiding CRT.

296 citations

Journal ArticleDOI
TL;DR: Systolic torsion in LV dysfunction was characterized by the discontinuing counter-rotation of the apex to the base before end-systole, and amplitude of systolicTorsion was impaired in proportion to LV function.
Abstract: Left ventricular (LV) torsion plays an important role in squeezing the blood out of the heart To characterize the systolic torsion in LV dysfunction, we studied using magnetic resonance imaging myocardial tagging method in 26 subjects: 17 patients with dilated cardiomyopathy (DCM, LV ejection fraction [EF], 27 +/- 8%) and 9 healthy control subjects Grid-tagged LV short-axis cine images were acquired at base, mid and apex levels Tag-intersections were tracked during the systole, thereby determining rotation angle (positive indicated clockwise from the apex) Peak torsion was defined as the maximum difference in rotation angle between the base and apex Time to peak torsion was expressed as % systole by dividing the time by a total systolic time Amplitude of the rotation at peak was less in DCM than in controls at both the base (01 +/- 29 vs 26 +/- 16 degrees , P < 005) and apex (-59 +/- 53 vs -112 +/- 25 degrees , P < 001) Amplitude of peak torsion was then less in DCM than in controls (61 +/- 34 vs 136 +/- 25 degrees , P < 0001), and the timing of peak was earlier (66 +/- 22 vs 104 +/- 16% systole, P < 0001) The amplitude of peak torsion was correlated with LVEF (r=074, P < 0001) In conclusion, amplitude of systolic torsion was impaired in proportion to LV function Systolic torsion in LV dysfunction was characterized by the discontinuing counter-rotation of the apex to the base before end-systole

114 citations

Journal ArticleDOI
14 May 2014-Heart
TL;DR: Large-extent LGE correlates with absence of LV functional improvement and high incidence of adverse outcomes in patients with CS after steroid therapy, including cardiac death, hospitalisation for heart failure, and life-threatening arrhythmias.
Abstract: Background Gadolinium-enhanced cardiovascular magnetic resonance is an emerging tool for the diagnosis of cardiac sarcoidosis (CS); however, the correlations between extent of late gadolinium enhancement (LGE) and efficacy of steroid therapy and adverse outcomes in patients with CS remain unclear. Objective We aimed to clarify the prognostic impact of extent of LGE in patients with CS. Methods Before the start of steroid therapy, 43 consecutive LGE-positive patients with CS were divided into two groups based on the extent of LGE by a median value: small-extent LGE (LGE mass Results Among the 6 patients who died from heart disorders, 11 patients who were hospitalised because of heart failure and 6 patients who suffered life-threatening arrhythmia during the follow-up period, large-extent LGE predicted higher incidences of cardiac mortality and hospitalisation for heart failure. Multivariate Cox regression analysis showed that large-extent LGE was independently associated with combined adverse outcomes including cardiac death, hospitalisation for heart failure, and life-threatening arrhythmias. In the small-extent LGE group, LV end-diastolic volume index significantly decreased and LVEF significantly increased after steroid therapy, whereas in the large-extent LGE group, neither LV volume nor LVEF changed substantially. Conclusions Large-extent LGE correlates with absence of LV functional improvement and high incidence of adverse outcomes in patients with CS after steroid therapy.

112 citations

Journal ArticleDOI
TL;DR: Famotidine improved both cardiac symptoms and ventricular remodeling associated with CHF and may have therapeutic benefits for CHF.

91 citations


Cited by
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Journal ArticleDOI
TL;DR: Authors/Task Force Members: Piotr Ponikowski* (Chairperson) (Poland), Adriaan A. Voors* (Co-Chair person) (The Netherlands), Stefan D. Anker (Germany), Héctor Bueno (Spain), John G. F. Cleland (UK), Andrew J. S. Coats (UK)

13,400 citations

Christopher M. Bishop1
01 Jan 2006
TL;DR: Probability distributions of linear models for regression and classification are given in this article, along with a discussion of combining models and combining models in the context of machine learning and classification.
Abstract: Probability Distributions.- Linear Models for Regression.- Linear Models for Classification.- Neural Networks.- Kernel Methods.- Sparse Kernel Machines.- Graphical Models.- Mixture Models and EM.- Approximate Inference.- Sampling Methods.- Continuous Latent Variables.- Sequential Data.- Combining Models.

10,141 citations

Journal ArticleDOI
TL;DR: ACCF/AHAIAI: angiotensin-converting enzyme inhibitor as discussed by the authors, angio-catabolizing enzyme inhibitor inhibitor inhibitor (ACS inhibitor) is a drug that is used to prevent atrial fibrillation.
Abstract: ACC/AHA : American College of Cardiology/American Heart Association ACCF/AHA : American College of Cardiology Foundation/American Heart Association ACE : angiotensin-converting enzyme ACEI : angiotensin-converting enzyme inhibitor ACS : acute coronary syndrome AF : atrial fibrillation

7,489 citations

01 Mar 2007
TL;DR: An initiative to develop uniform standards for defining and classifying AKI and to establish a forum for multidisciplinary interaction to improve care for patients with or at risk for AKI is described.
Abstract: Acute kidney injury (AKI) is a complex disorder for which currently there is no accepted definition. Having a uniform standard for diagnosing and classifying AKI would enhance our ability to manage these patients. Future clinical and translational research in AKI will require collaborative networks of investigators drawn from various disciplines, dissemination of information via multidisciplinary joint conferences and publications, and improved translation of knowledge from pre-clinical research. We describe an initiative to develop uniform standards for defining and classifying AKI and to establish a forum for multidisciplinary interaction to improve care for patients with or at risk for AKI. Members representing key societies in critical care and nephrology along with additional experts in adult and pediatric AKI participated in a two day conference in Amsterdam, The Netherlands, in September 2005 and were assigned to one of three workgroups. Each group's discussions formed the basis for draft recommendations that were later refined and improved during discussion with the larger group. Dissenting opinions were also noted. The final draft recommendations were circulated to all participants and subsequently agreed upon as the consensus recommendations for this report. Participating societies endorsed the recommendations and agreed to help disseminate the results. The term AKI is proposed to represent the entire spectrum of acute renal failure. Diagnostic criteria for AKI are proposed based on acute alterations in serum creatinine or urine output. A staging system for AKI which reflects quantitative changes in serum creatinine and urine output has been developed. We describe the formation of a multidisciplinary collaborative network focused on AKI. We have proposed uniform standards for diagnosing and classifying AKI which will need to be validated in future studies. The Acute Kidney Injury Network offers a mechanism for proceeding with efforts to improve patient outcomes.

5,467 citations

Journal ArticleDOI
TL;DR: The Society of Echocardiography (SEDC) is an educational activity for cardiovascular physicians and cardiac sonographers with a knowledge base in the field of echo-cardiography as discussed by the authors.
Abstract: on Statement: Society of Echocardiography is accreditedby theAccreditationCouncil for edical Education to provide continuingmedical education for physicians. n Society of Echocardiography designates this educational activity for of 1.0 AMA PRA Category 1 Credits . Physicians should only claim credit te with the extent of their participation in the activity. CCI recognize ASE’s certificates and have agreed to honor the credit hours registry requirements for sonographers. Society of Echocardiography is committed to ensuring that its educational ll sponsored educational programs are not influencedby the special interests ation or individual, and itsmandate is to retain only those authors whose fists canbeeffectively resolved tomaintain thegoals andeducational integrity y. While a monetary or professional affiliation with a corporation does not fluence an author’s presentation, the Essential Areas and policies of the ire that any relationships that could possibly conflict with the educational activity be resolved prior to publication and disclosed to the audience. f faculty and commercial support relationships, if any, have been indicated. ience: is designed for all cardiovascular physicians and cardiac sonographers with erest and knowledge base in the field of echocardiography; in addition, reschers, clinicians, intensivists, and other medical professionals with a spein cardiac ultrasound will find this activity beneficial.

5,151 citations