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Myocardial Scar (myocardial + scar)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Clinical Application of PET/CT Fusion Imaging for Three-Dimensional Myocardial Scar and Left Ventricular Anatomy during Ventricular Tachycardia Ablation

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2009
JING TIAN M.D., Ph.D.
Background: Image integration has the potential to display three-dimensional (3D) scar anatomy and facilitate substrate characterization for ventricular tachycardia (VT) ablation. However, the current generation of clinical mapping systems cannot display 3D left ventricle (LV) anatomy with embedded 3D scar reconstructions or allow display of border zone and high-resolution anatomic scar features. Objective: This study reports the first clinical experience with a mapping system allowing an integrated display of 3D LV anatomy with detailed 2D/3D scar and border zone reconstruction. Methods: Ten patients scheduled for VT ablation underwent contrast-enhanced computed tomography (CT) and Rubidium-82 perfusion/F-18 Fluorodeoxyglucose metabolic Positron Emission Tomography (PET) imaging to reconstruct 3D LV and scar anatomy. LV and scar models were co-registered using a 3D mapping system and analyzed with a 17-segment model. Metabolic thresholding was used to reconstruct the 3D border zone. Real-time display of CT images was performed during ablation. Results: Co-registration (error 4.3 ± 0.7 mm) allowed simultaneous visualization of 3D LV anatomy and embedded scar and guided additional voltage mapping. Segments containing homogenous or partial scar correlated in 94.4% and 85.7% between voltage maps and 3D PET scar reconstructions, respectively. Voltage-defined scar and normal myocardium had relative FDG uptakes of 40 ± 13% and 89 ± 30% (P < 0.05). The 3D border zone correlated best with a 46% metabolic threshold. Real-time display of registered high-resolution CT images allowed the simultaneous characterization of scar-related anatomic changes. Conclusion: Integration of PET/CT reconstruction allows simultaneous 3D display of myocardial scar and border zone embedded into the LV anatomy as well as the display of detailed scar anatomy. Multimodality imaging may enable a new image-guided approach to substrate-guided VT ablation. [source]

Ablation of Atrial Flutter in a Patient with a Tricuspid Valve Replacement after Endocarditis

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2009
PETER NORDBECK M.D.
Myocardial scars from heart surgery are a source of tachycardia, eventually causing late morbidity and sudden death. In general, catheter ablation has been shown to be an effective therapy for various rhythm disorders, but it has been rarely described after atrioventricular valve replacement. We report on a 45-year-old man who developed atrial flutter after implantation of a tricuspid valve bioprosthesis. An electrophysiological investigation revealed typical type-I counterclockwise atrial flutter that was successfully terminated by catheter ablation. A sinus rhythm was restored and remained stable during the course of treatment; the valvular function was not diminished. It is demonstrated that safe mapping and ablation of typical atrial flutter is possible after a tricuspid valve replacement. [source]

Clinical Application of PET/CT Fusion Imaging for Three-Dimensional Myocardial Scar and Left Ventricular Anatomy during Ventricular Tachycardia Ablation

Cardiovascular magnetic resonance in mild to moderate clozapine-induced myocarditis: Is there a role in the absence of electrocardiographic and echocardiographic abnormalities?

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2010
Vignendra Ariyarajah MD
Abstract Clozapine is an atypical, neuroleptic medication that can cause myocarditis. While the "gold standard" for diagnosis of myocarditis is perceived to be via myocardial biopsy, cardiovascular magnetic resonance (CMR) has also proven its utility in this respect, primarily through its ability to detect myocardial scar by late-gadolinium enhancement (LGE). Until recently, however, clozapine-induced myocarditis specifically has not been known to be associated with LGE on CMR. In that particular case, LGE was demonstrated in a patient with clozapine-induced myocarditis. However, quite important, that patient also had specific abnormalities on the electrocardiogram (ECG) and echocardiogram that corresponded to the area of LGE demonstrated by CMR. We highlight a case series of three patients with clozapine-induced myocarditis and provide a literature review to discuss and critically appraise the true incremental diagnostic value of CMR in such patients with normal ECG and echocardiography. J. Magn. Reson. Imaging 2010;31:1473,1476. © 2010 Wiley-Liss, Inc. [source]

Fragmented QRS Complexes on 12-Lead ECG: A Marker of Cardiac Sarcoidosis as Detected by Gadolinium Cardiac Magnetic Resonance Imaging

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2009
Mohamed Homsi M.D.
Background: Fragmented QRS complexes (fQRS) on a 12-lead ECG are a marker of myocardial scar in patients with coronary artery disease. Cardiac sarcoidosis is also associated with myocardial granuloma formation and scarring. We evaluated the significance of fQRS on a 12-lead ECG compared to Gadolinium-delayed enhancement images (GDE) in cardiac magnetic resonance imaging (CMR). Method and results: The ECGs of patients (n = 17, mean age: 52 ± 11 years, male: 53%) with established diagnosis of sarcoidosis who underwent a CMR for evaluation of cardiac involvement were studied. ECG abnormalities included bundle branch block, Q wave, and fQRS. fQRS, Q wave, and bundle branch block were present in 9 (53%), 1 (6%), and 4 (24%) patients, respectively. The sensitivity and specificity of fQRS for detecting abnormal GDE were 100% and 80%, respectively. Sensitivity and specificity of Q waves were 11% and 100%, respectively. Conclusions: fQRS on a 12-lead ECG in patients with suspected cardiac sarcoidosis are associated with cardiac involvement as detected by GDE on CMR. [source]

Computer-assisted calculation of myocardial infarct size shortens the evaluation time of contrast-enhanced cardiac MRI

CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2008
Lene Rosendahl
Summary Background:, Delayed enhancement magnetic resonance imaging depicts scar in the left ventricle which can be quantitatively measured. Manual segmentation and scar determination is time consuming. The purpose of this study was to evaluate a software for infarct quantification, to compare with manual scar determination, and to measure the time saved. Methods:, Delayed enhancement magnetic resonance imaging was performed in 40 patients where myocardial perfusion single photon emission computed tomography imaging showed irreversible uptake reduction suggesting a myocardial scar. After segmentation, the semi-automatic software was applied. A scar area was displayed, which could be corrected and compared with manual delineation. The different time steps were recorded with both methods. Results:, The software shortened the average evaluation time by 12·4 min per cardiac exam, compared with manual delineation. There was good correlation of myocardial volume, infarct volume and infarct percentage (%) between the two methods, r = 0·95, r = 0·92 and r = 0·91 respectively. Conclusion:, A computer software for myocardial volume and infarct size determination cut the evaluation time by more than 50% compared with manual assessment, with maintained clinical accuracy. [source]

Transcoronary transplantation of autologous mesenchymal stem cells and endothelial progenitors into infarcted human myocardium

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005
Demosthenes G. Katritsis MD PhD
Abstract The aim of the study was to investigate whether a combination of mesenchymal stem cells (MSCs) capable of differentiating into cardiac myocytes and endothelial progenitors (EPCs) that mainly promote neoangiogenesis might be able to facilitate tissue repair in myocardial scars. Previous studies have shown that intracoronary transplantation of autologous bone marrow stem cells results in improvement of contractility in infracted areas of human myocardium. Eleven patients with an anteroseptal myocardial infarction (MI) underwent transcoronary transplantation of bone marrow-derived MSCs and EPCs to the infarcted area through the left anterior descending artery. Eleven age- and sex-matched patients served as controls. Wall motion score index was significantly lower at follow-up in the transplantation (P = 0.04) but not in the control group. On stress echocardiography, there was improvement of myocardial contractility in one or more previously nonviable myocardial segments in 5 out of 11 patients (all with recent infarctions) and in none of the controls (P = 0.01). Restoration of uptake of Tc99m sestamibi in one or more previously nonviable myocardial scars was seen in 6 out of 11 patients subjected to transplantation and in none of the controls (P = 0.02). Cell transplantation was an independent predictor of improvement of nonviable tissue. Intracoronary transplantation of MSCs and EPCs is feasible, safe, and may contribute to regional regeneration of myocardial tissue early or late following MI. © 2005 Wiley-Liss, Inc. [source]