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Ventricular spiral

Angie M Y Shum, Hui Che, Andy On-Tik Wong, Chenzi Zhang, Hongkai Wu, Camie W Y Chan, Kevin Costa, Michelle Khine, Chi-Wing Kong, Ronald A Li
A novel cardiomimetic biohybrid material, termed as the human ventricular cardiac anisotropic sheet (hvCAS) is reported. Well-characterized human pluripotent stem cell-derived ventricular cardiomyocytes were strategically aligned to reproduce key electrophysiological features of native human ventricle, which, along with specific selection criteria, allows for a direct visualization of arrhythmic spiral re-entry and represents a revolutionary tool to assess preclinical drug-induced arrhythmogenicity.
November 2, 2016: Advanced Materials
Dae Woo Park, Andrea Sebastiani, Choon Hwai Yap, Marc A Simon, Kang Kim
Mechanical and structural changes of right ventricular (RV) in response to pulmonary hypertension (PH) are inadequately understood. While current standard biaxial testing provides information on the mechanical behavior of RV tissues using surface markers, it is unable to fully assess structural and mechanical properties across the full tissue thickness. In this study, the mechanical and structural properties of normotensive and pulmonary hypertension right ventricular (PHRV) myocardium through its full thickness were examined using mechanical testing combined with 3D ultrasound speckle tracking (3D-UST)...
2016: PloS One
M C Burg, P Lunkenheimer, P Niederer, C Brune, K Redmann, M Smerup, U Spiegel, F Becker, D Maintz, W Heindel, R H Anderson
Purpose: There are ongoing arguments as to how cardiomyocytes are aggregated together within the ventricular walls. We used pneumatic distension through the coronary arteries to exaggerate the gaps between the aggregated cardiomyocytes, analyzing the pattern revealed using computed tomography, and validating our findings by histology. Methods: We distended 10 porcine hearts, arresting 4 in diastole by infusion of cardioplegic solutions, and 4 in systole by injection of barium chloride. Mural architecture was revealed by computed tomography, measuring also the angulations of the long chains of cardiomyocytes...
November 2016: RöFo: Fortschritte Auf Dem Gebiete der Röntgenstrahlen und der Nuklearmedizin
Hemant Chaturvedi, Rudra Dev Pandey, Krishna Kumar Sharma, Jitendra Singh Makkar, Sanjeev K Sharma
We present a patient with asymptomatic apical hypertrophic cardiomyopathy (AHCM) who recently developed cardiac arrhythmias, and shortly discuss the diagnostic modalities, differential diagnosis, and treatment strategy for this condition. AHCM is a rare form of hypertrophic cardiomyopathy, which usually involves the apex of the left ventricle. AHCM can occur with varied presentations such as chest pain, palpitations, dyspnea, syncope, atrial fibrillation, myocardial infarction, embolic events, ventricular fibrillation, and congestive heart failure...
September 2016: Indian Heart Journal
Gary Tse, Bryan P Yan
Sudden cardiac death, frequently due to ventricular arrhythmias, is a significant problem globally. Most affected individuals do not arrive at hospital in time for medical treatment. Therefore, there is an urgent need to identify the most-at-risk patients for insertion of prophylactic implantable cardioverter defibrillators. Clinical risk markers derived from electrocardiography are important for this purpose. They can be based on repolarization, including corrected QT (QTc) interval, QT dispersion (QTD), interval from the peak to the end of the T-wave (Tpeak - Tend), (Tpeak - Tend)/QT, T-wave alternans (TWA), and microvolt TWA...
October 4, 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Michael R Pinsky
The primary role of the right ventricle (RV) is to deliver all the blood it receives per beat into the pulmonary circulation without causing right atrial pressure to rise. To the extent that it also does not impede left ventricular (LV) filling, cardiac output responsiveness to increased metabolic demand is optimized. Since cardiac output is a function of metabolic demand of the body, during stress and exercise states the flow to the RV can vary widely. Also, instantaneous venous return varies widely for a constant cardiac output as ventilatory efforts alter the dynamic pressure gradient for venous return...
September 10, 2016: Critical Care: the Official Journal of the Critical Care Forum
Sean M Hamlet, Christopher M Haggerty, Jonathan D Suever, Gregory J Wehner, Jonathan D Grabau, Kristin N Andres, Moriel H Vandsburger, David K Powell, Vincent L Sorrell, Brandon K Fornwalt
BACKGROUND: Advanced cardiovascular magnetic resonance (CMR) acquisitions often require long scan durations that necessitate respiratory navigator gating. The tradeoff of navigator gating is reduced scan efficiency, particularly when the patient's breathing patterns are inconsistent, as is commonly seen in children. We hypothesized that engaging pediatric participants with a navigator-controlled videogame to help control breathing patterns would improve navigator efficiency and maintain image quality...
2016: Journal of Cardiovascular Magnetic Resonance
Robert H Anderson, Shumpei Mori, Diane E Spicer, Nigel A Brown, Timothy J Mohun
It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts...
September 2016: World Journal for Pediatric & Congenital Heart Surgery
Sergio Alonso, Markus Bär, Blas Echebarria
The beating of the heart is a synchronized contraction of muscle cells (myocytes) that is triggered by a periodic sequence of electrical waves (action potentials) originating in the sino-atrial node and propagating over the atria and the ventricles. Cardiac arrhythmias like atrial and ventricular fibrillation (AF,VF) or ventricular tachycardia (VT) are caused by disruptions and instabilities of these electrical excitations, that lead to the emergence of rotating waves (VT) and turbulent wave patterns (AF,VF)...
September 2016: Reports on Progress in Physics
Sean M Hamlet, Christopher M Haggerty, Jonathan D Suever, Gregory J Wehner, Kristin N Andres, David K Powell, Xiaodong Zhong, Brandon K Fornwalt
PURPOSE: To determine the optimal respiratory navigator gating configuration for the quantification of left ventricular strain using spiral cine displacement encoding with stimulated echoes (DENSE) MRI. MATERIALS AND METHODS: Two-dimensional spiral cine DENSE was performed on a 3 Tesla MRI using two single-navigator configurations (retrospective, prospective) and a combined "dual-navigator" configuration in 10 healthy adults and 20 healthy children. The adults also underwent breathhold DENSE as a reference standard for comparisons...
July 26, 2016: Journal of Magnetic Resonance Imaging: JMRI
Suneet Mittal, Devi Nair, Benzy J Padanilam, Allen Ciuffo, Nigel Gupta, Peter Gallagher, Bruce Goldner, Eric F Hammill, Nicolas Wold, Kenneth Stein, Martin Burke
INTRODUCTION: The safety and efficacy of a novel family of quadripolar left ventricular (LV) pacing leads designed to pace from nonapical regions of the LV with low pacing capture thresholds was studied in patients undergoing implantation of a cardiac resynchronization therapy defibrillator (CRT-D). METHODS AND RESULTS: Patients receiving a CRT-D were implanted with 1 of 3 ACUITY X4 leads (Spiral Long, Spiral Short, or Straight), designed to address coronary venous anatomical variability...
October 2016: Journal of Cardiovascular Electrophysiology
Yasunori Kushiyama, Haruo Honjo, Ryoko Niwa, Hiroki Takanari, Masatoshi Yamazaki, Yoshio Takemoto, Ichiro Sakuma, Itsuo Kodama, Kaichiro Kamiya
It has been reported that blockade of the inward rectifier K(+) current (IK1) facilitates termination of ventricular fibrillation. We hypothesized that partial IK1 blockade destabilizes spiral wave (SW) re-entry, leading to its termination. Optical action potential (AP) signals were recorded from left ventricles of Langendorff-perfused rabbit hearts with endocardial cryoablation. The dynamics of SW re-entry were analyzed during ventricular tachycardia (VT), induced by cross-field stimulation. Intercellular electrical coupling in the myocardial tissue was evaluated by the space constant...
September 1, 2016: American Journal of Physiology. Heart and Circulatory Physiology
Eric J Stöhr, Rob E Shave, Aaron L Baggish, Rory B Weiner
The anatomy of the adult human left ventricle (LV) is the result of its complex interaction with its environment. From the fetal to the neonatal to the adult form, the human LV undergoes an anatomical transformation that finally results in the most complex of the four cardiac chambers. In its adult form, the human LV consists of two muscular helixes that surround the midventricular circumferential layer of muscle fibers. Contraction of these endocardial and epicardial helixes results in a twisting motion that is thought to minimize the transmural stress of the LV muscle...
September 1, 2016: American Journal of Physiology. Heart and Circulatory Physiology
Pratibha Nair, Abdul Rezzak Hamzeh, Madiha Mohamed, Ethar Mustafa Malik, Mahmoud Taleb Al-Ali, Fatma Bastaki
ECHS1 is a mitochondrial matrix enzyme that catalyzes an important step in the β-oxidation spiral of fatty acid catabolism, and individuals with mutations in the ECHS1 gene suffer from an autosomal recessive condition typified by delayed psychomotor development, mitochondrial encephalopathy, hypotonia, and cardiomyopathy. Here we report the first Arab case of ECHS1 Deficiency. The patient was born to consanguineous parents with all growth parameters being low for gestational age, and was persistently desaturated...
October 2016: Metabolic Brain Disease
Yan-Jing Wang, Lin Liu, Meng-Chao Zhang, Huan Sun, Hong Zeng, Ping Yang
INTRODUCTION: Phrenic nerve injury and diaphragmatic stimulation are common complications following arrhythmia ablation and pacing therapies. Preoperative comprehension of phrenic nerve anatomy via non-invasive CT imaging may help to minimize the electrophysiological procedure-related complications. METHODS: Coronary CT angiography data of 121 consecutive patients were collected. Imaging of left and right pericardiophrenic bundles was performed with volume rendering and multi-planar reformation techniques...
August 2016: Journal of Cardiovascular Electrophysiology
David Filgueiras-Rama, José Jalife
Evidence accumulated over the last 25 years suggests that, whether in the atria or ventricles, fibrillation may be explained by the self-organization of the cardiac electrical activity into rapidly spinning rotors giving way to spiral waves that break intermittently and result in fibrillatory conduction. The dynamics and frequency of such rotors depend on the ion channel composition, excitability and refractory properties of the tissues involved, as well as on the thickness and respective three-dimensional fiber structure of the atrial and ventricular chambers...
February 1, 2016: JACC. Clinical Electrophysiology
Julia Kar, Brian Cupps, Xiaodong Zhong, Danielle Koerner, Kevin Kulshrestha, Samuel Neudecker, Jennifer Bell, Heidi Craddock, Michael Pasque
PURPOSE: To describe and assess an automated normalization method for identifying sentinel (septal) regions of myocardial dysfunction in nonischemic, nonvalvular dilated cardiomyopathy (DCM), using an unprecedented combination of the navigator-gated 3D spiral displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI), radial point interpolation (RPIM) and multiparametric strain z-score (MPZS). MATERIALS AND METHODS: Navigator-gated 3D spiral DENSE, in a 1...
October 2016: Journal of Magnetic Resonance Imaging: JMRI
Carsten Rickers, Arash Kheradvar, Hans-Hinrich Sievers, Ahmad Falahatpisheh, Philip Wegner, Dominik Gabbert, Michael Jerosch-Herold, Chris Hart, Inga Voges, Léon M Putman, Ines Kristo, Gunther Fischer, Jens Scheewe, Hans-Heiner Kramer
OBJECTIVES: To compare the Lecompte technique and the spiral anastomosis (complete anatomic correction) two decades after arterial switch operation (ASO). METHODS: Nine patients after primary ASO with Lecompte and 6 selected patients after spiral anastomosis were evaluated 20.8 ± 2.1 years after ASO versus matched controls. Blood flow dynamics and flow profiles (e.g. vorticity, helicity) in the great arteries were quantified from time-resolved 3D magnetic resonance imaging (MRI) phase contrast flow measurements (4D flow MR) in addition to a comprehensive anatomical and functional cardiovascular MRI analysis...
June 2016: Interactive Cardiovascular and Thoracic Surgery
Motoo Nakagawa, Yoshiyuki Ozawa, Norikazu Nomura, Sachiko Inukai, Satoshi Tsubokura, Keita Sakurai, Masashi Shimohira, Masaki Ogawa, Yuta Shibamoto
PURPOSE: We evaluated the ability of dual source CT (DSCT) with ECG-triggered high-pitch spiral acquisition (Flash Spiral Cardio mode) to depict the morphological features of ventricles in pediatric patients with congenital heart defects (CHD). MATERIALS AND METHODS: Between July 2013 and April 2015, 78 pediatric patients with CHD (median age 4 months) were examined using DSCT with the Flash Spiral Cardio mode. The types of ventricular abnormalities were ventricular septal defect (VSD) in 42 (the malaligned type in 11, perimembranous type in 23, supracristal type in 2, atrioventricular type in 2, and muscular type in 4), single ventricle (SV) in 11, and congenital corrected transposition of the great arteries (ccTGA) in 4...
April 2016: Japanese Journal of Radiology
Eva R Serber, Joseph L Fava, Lillian M Christon, Alfred E Buxton, Jeffrey J Goldberger, Michael R Gold, James R Rodrigue, Michael B Frisch
BACKGROUND: Improving mental and physical health of patients with implantable cardioverter defibrillators (ICD) is critical because this group is at high risk for ventricular arrhythmias and sudden death and depressed or anxious cardiovascular disease (CVD) patients appear to be at even higher risk for mortality compared to nondepressed or nonanxious CVD patients. Further, autonomic dysfunction is present in these patients, and negative emotions and arrhythmias form a downward spiral further worsening mood, well-being, and cardiovascular health...
May 2016: Pacing and Clinical Electrophysiology: PACE
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