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Silvia G Priori - One of the best experts on this subject based on the ideXlab platform.
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Clinical utility gene card for: Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT).
European journal of human genetics : EJHG, 2013Co-Authors: Carlo Napolitano, Raffaella Bloise, Mirella Memmi, Silvia G PrioriAbstract:Name of the disease (synonyms): Synonyms: Familial Polymorphic Ventricular Tachycardia (FPVT), catecholamine-induced Polymorphic Ventricular Tachycardia (CPVT). Includes: RYR2-related catecholaminergic Ventricular Tachycardia, CASQ2-related catecholaminergic Ventricular Tachycardia OMIM# of the disease: 604772, 611938 Name of the analysed genes or DNA/chromosome segments: RyR2, cardiac ryanodine receptor OMIM# of the gene(s): 180902, 114251 Two genes are clearly associated with CPVT (RyR2 autosomal dominant, and CASQ2 autosomal recessive). Triadin mutations have been also shown in two CPVT families but data need confirmation. Therefore, clinical testing is not indicated. Review of the analytical and clinical validity as well as of the clinical utility of DNA-based testing for mutations in the RyR2 gene in diagnostic, predictive and prenatal settings and for risk assessment in relatives.
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Role of calmodulin kinase in catecholaminergic Polymorphic Ventricular Tachycardia.
Heart rhythm, 2011Co-Authors: Carlo Napolitano, Nian Liu, Silvia G PrioriAbstract:g t Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is an inherited disease causing arrhythmias and sudden death in the structurally normal heart. Affected patients have a typical pattern of stress-induced atrial (supraVentricular Tachycardia and atrial fibrillation) and Ventricular (bidirectional/Polymorphic Ventricular Tachycardia and Ventricular fibrillation) arrhythmias. The resting electrocardiogram of CPVT patients is normal, while arrhythmias can be reproducibly triggered by sudden adrenergic activation (exercise or acute emotion). In 2001, we were the first to demonstrate that autosomal dominant CPVT is caused by mutations in the cardiac ryanodine receptor (RyR2), the Ca -releasing channel of the cardiac sarcoplasmic reticulum (SR), which is a key player of the calcium-induced calcium release process; several other groups confirmed this finding afterward. Another Ca handling-related protein, calsequestrin (CASQ2), has been linked to the rare autosomal recessive CPVT variant. Thus, CPVT pathogenesis is intrinsically bound to catecholamines and Ca handling. Cardiac Ca /calmodulin-dependent protein kinase (CaMKII) is an intracellular mediator of the adrenergic cascade, and it specifically modulates Ca homeostasis (by romoting phosphorylation of multiple Ca -handling proeins including RyR2). The CaMKII isoform delta, splice ariant c (CaMKII -c), is mostly expressed in the cytoplasm of the cardiac myocytes. It follows that not only is CaMKII -c (hereafter defined as CaMKII) a potential im-
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The long QT syndrome and catecholaminergic Polymorphic Ventricular Tachycardia.
Pacing and Clinical Electrophysiology, 2009Co-Authors: Nicola Monteforte, Silvia G PrioriAbstract:Thanks to the contribution of molecular genetics, the genetic bases, the pathogenesis and genotype-phenotype correlation of diseases such as the long QT syndrome and catecholaminergic Polymorphic Ventricular Tachycardia have been progressively unveiled and show an extremely high degree of genetic heterogeneity. Data from clinical registries are summarized together with the recommendations provided in clinical practice guidelines for management of patients with these diseases. Furthermore the evidence supporting the importance of genetic analysis for risk stratification and therapy selections is reviewed.
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catecholaminergic Polymorphic Ventricular Tachycardia
Progress in Cardiovascular Diseases, 2008Co-Authors: Nian Liu, Yanfei Ruan, Silvia G PrioriAbstract:Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is a highly malignant form of arrhythmogenic disorder characterized by exercise- or emotional-induced Polymorphic Ventricular Tachycardia in the absence of detectable structural heart disease. Because of the typical pattern of arrhythmias (bidirectional Ventricular Tachycardia and the occurrence and severity of arrhythmia correlated well with exercise workload) during exercise stress test, CPVT can be identified promptly. Molecular genetic screening of the genes encoding the cardiac ryanodine receptor and calsequestrin is critical to confirm uncertain diagnosis of CPVT. With the exception of β -blockers, no pharmacologic therapy of proven effectiveness is available: although β -blockers reduce the occurrence of Ventricular Tachycardia, 30% of patients treated with β -blockers still experience cardiac arrhythmias and eventually require implantable cardioverter defibrillator implantation to prevent cardiac arrest.
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Catecholaminergic Polymorphic Ventricular Tachycardia.
Herz, 2007Co-Authors: Nian Liu, Raffaella Bloise, Barbara Colombi, Emilia Raytcheva-buono, Silvia G PrioriAbstract:Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is a highly lethal form of inherited arrhythmogenic disease characterized by adrenergically mediated Polymorphic Ventricular Tachycardia. The mutations in cardiac ryanodine receptor and calsequestrin genes are responsible for the autosomal dominant and recessive variants of CPVT, respectively. The clinical presentation encompasses exercise- or emotion-induced syncopal events and a distinctive pattern of reproducible, stress-related, bidirectional Ventricular Tachycardia in the absence of both structural heart disease and a prolonged QT interval. The mortality rate in untreated individuals is 30-50% by age 40. Clinical evaluation by exercise stress testing and holter monitoring and genetic screening can facilitate early diagnosis. beta-adrenergic blockers are the most effective pharmacological treatment in controlling arrhythmias in CPVT patients, yet about 30% of patients still experience cardiac arrhythmias and eventually require an implantable cardioverter defibrillator.
Carlo Napolitano - One of the best experts on this subject based on the ideXlab platform.
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Clinical utility gene card for: Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT).
European journal of human genetics : EJHG, 2013Co-Authors: Carlo Napolitano, Raffaella Bloise, Mirella Memmi, Silvia G PrioriAbstract:Name of the disease (synonyms): Synonyms: Familial Polymorphic Ventricular Tachycardia (FPVT), catecholamine-induced Polymorphic Ventricular Tachycardia (CPVT). Includes: RYR2-related catecholaminergic Ventricular Tachycardia, CASQ2-related catecholaminergic Ventricular Tachycardia OMIM# of the disease: 604772, 611938 Name of the analysed genes or DNA/chromosome segments: RyR2, cardiac ryanodine receptor OMIM# of the gene(s): 180902, 114251 Two genes are clearly associated with CPVT (RyR2 autosomal dominant, and CASQ2 autosomal recessive). Triadin mutations have been also shown in two CPVT families but data need confirmation. Therefore, clinical testing is not indicated. Review of the analytical and clinical validity as well as of the clinical utility of DNA-based testing for mutations in the RyR2 gene in diagnostic, predictive and prenatal settings and for risk assessment in relatives.
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Paradoxical Effect of Increased Diastolic Ca 2+ Release and Decreased Sinoatrial Node Activity in a Mouse Model of Catecholaminergic Polymorphic Ventricular Tachycardia
Circulation, 2012Co-Authors: Patricia Neco, Angelo Torrente, Pietro Mesirca, Esther Zorio, Nian Liu, Silvia Priori, Carlo Napolitano, Sylvain Richard, Jean-pierre Benitah, Matteo E. MangoniAbstract:Catecholaminergic Polymorphic Ventricular Tachycardia is characterized by stress-triggered syncope and sudden death. Patients with catecholaminergic Polymorphic Ventricular Tachycardia manifest sinoatrial node (SAN) dysfunction, the mechanisms of which remain unexplored.
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paradoxical effect of increased diastolic ca2 release and decreased sinoatrial node activity in a mouse model of catecholaminergic Polymorphic Ventricular Tachycardia
Circulation, 2012Co-Authors: Patricia Neco, Pietro Mesirca, Esther Zorio, Nian Liu, Silvia Priori, Carlo Napolitano, Sylvain Richard, Jean-pierre Benitah, Angelo G Torrente, Matteo E. MangoniAbstract:Background—Catecholaminergic Polymorphic Ventricular Tachycardia is characterized by stress-triggered syncope and sudden death. Patients with catecholaminergic Polymorphic Ventricular Tachycardia manifest sinoatrial node (SAN) dysfunction, the mechanisms of which remain unexplored. Methods and Results—We investigated SAN [Ca2+]i handling in mice carrying the catecholaminergic Polymorphic Ventricular Tachycardia–linked mutation of ryanodine receptor (RyR2R4496C) and their wild-type (WT) littermates. In vivo telemetric recordings showed impaired SAN automaticity in RyR2R4496C mice after isoproterenol injection, analogous to what was observed in catecholaminergic Polymorphic Ventricular Tachycardia patients after exercise. Pacemaker activity was explored by measuring spontaneous [Ca2+]i transients in SAN cells within the intact SAN by confocal microscopy. RyR2R4496C SAN presented significantly slower pacemaker activity and impaired chronotropic response under β-adrenergic stimulation, accompanied by the appe...
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Role of calmodulin kinase in catecholaminergic Polymorphic Ventricular Tachycardia.
Heart rhythm, 2011Co-Authors: Carlo Napolitano, Nian Liu, Silvia G PrioriAbstract:g t Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is an inherited disease causing arrhythmias and sudden death in the structurally normal heart. Affected patients have a typical pattern of stress-induced atrial (supraVentricular Tachycardia and atrial fibrillation) and Ventricular (bidirectional/Polymorphic Ventricular Tachycardia and Ventricular fibrillation) arrhythmias. The resting electrocardiogram of CPVT patients is normal, while arrhythmias can be reproducibly triggered by sudden adrenergic activation (exercise or acute emotion). In 2001, we were the first to demonstrate that autosomal dominant CPVT is caused by mutations in the cardiac ryanodine receptor (RyR2), the Ca -releasing channel of the cardiac sarcoplasmic reticulum (SR), which is a key player of the calcium-induced calcium release process; several other groups confirmed this finding afterward. Another Ca handling-related protein, calsequestrin (CASQ2), has been linked to the rare autosomal recessive CPVT variant. Thus, CPVT pathogenesis is intrinsically bound to catecholamines and Ca handling. Cardiac Ca /calmodulin-dependent protein kinase (CaMKII) is an intracellular mediator of the adrenergic cascade, and it specifically modulates Ca homeostasis (by romoting phosphorylation of multiple Ca -handling proeins including RyR2). The CaMKII isoform delta, splice ariant c (CaMKII -c), is mostly expressed in the cytoplasm of the cardiac myocytes. It follows that not only is CaMKII -c (hereafter defined as CaMKII) a potential im-
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clinical and molecular characterization of patients with catecholaminergic Polymorphic Ventricular Tachycardia
Circulation, 2002Co-Authors: Silvia G Priori, Carlo Napolitano, Raffaella Bloise, Barbara Colombi, Mirella Memmi, Fabrizio Drago, M Gasparini, Luciano Desimone, Fernando Coltorti, Roberto KeeganAbstract:Background— Mutations in the cardiac ryanodine receptor gene (RyR2) underlie catecholaminergic Polymorphic Ventricular Tachycardia (CPVT), an inherited arrhythmogenic disease occurring in the structurally intact heart. The proportion of patients with CPVT carrying RyR2 mutations is unknown, and the clinical features of RyR2-CPVT as compared with nongenotyped CPVT are undefined. Methods and Results— Patients with documented Polymorphic Ventricular arrhythmias occurring during physical or emotional stress with a normal heart entered the study. The clinical phenotype of the 30 probands and of 118 family members was evaluated, and mutation screening on the RyR2 gene was performed. Arrhythmias documented in probands were: 14 of 30 bidirectional Ventricular Tachycardia, 12 of 30 Polymorphic Ventricular Tachycardia, and 4 of 30 catecholaminergic idiopathic Ventricular fibrillation; RyR2 mutations were identified in 14 of 30 probands (36% bidirectional Ventricular Tachycardia, 58% Polymorphic Ventricular tachycar...
Roland R Brandt - One of the best experts on this subject based on the ideXlab platform.
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bradycardia induced Polymorphic Ventricular Tachycardia after atrioVentricular junction ablation for sinus Tachycardia induced cardiomyopathy
Journal of Cardiovascular Electrophysiology, 1995Co-Authors: Roland R Brandt, M Winkuang D ShenAbstract:In a patient with severe left Ventricular dysfunction resulting from chronic nonparoxysmal sinus Tachycardia, rate control and improvement in left Ventricular function were achieved with atrioVentricular junction ablation and Ventricular pacemaker implantation. Within 12 hours after the ablation procedure, several episodes of Polymorphic Ventricular Tachycardia that may have been triggered by the abruptly decreased heart rate occurred. Recurrence of Polymorphic Ventricular Tachycardia was prevented by an increase in pacing rate.
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Bradycardia‐Induced Polymorphic Ventricular Tachycardia After AtrioVentricular Junction Ablation for Sinus Tachycardia‐Induced Cardiomyopathy
Journal of cardiovascular electrophysiology, 1995Co-Authors: Roland R Brandt, Win-kuang ShenAbstract:In a patient with severe left Ventricular dysfunction resulting from chronic nonparoxysmal sinus Tachycardia, rate control and improvement in left Ventricular function were achieved with atrioVentricular junction ablation and Ventricular pacemaker implantation. Within 12 hours after the ablation procedure, several episodes of Polymorphic Ventricular Tachycardia that may have been triggered by the abruptly decreased heart rate occurred. Recurrence of Polymorphic Ventricular Tachycardia was prevented by an increase in pacing rate.
Matteo E. Mangoni - One of the best experts on this subject based on the ideXlab platform.
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Paradoxical Effect of Increased Diastolic Ca 2+ Release and Decreased Sinoatrial Node Activity in a Mouse Model of Catecholaminergic Polymorphic Ventricular Tachycardia
Circulation, 2012Co-Authors: Patricia Neco, Angelo Torrente, Pietro Mesirca, Esther Zorio, Nian Liu, Silvia Priori, Carlo Napolitano, Sylvain Richard, Jean-pierre Benitah, Matteo E. MangoniAbstract:Catecholaminergic Polymorphic Ventricular Tachycardia is characterized by stress-triggered syncope and sudden death. Patients with catecholaminergic Polymorphic Ventricular Tachycardia manifest sinoatrial node (SAN) dysfunction, the mechanisms of which remain unexplored.
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paradoxical effect of increased diastolic ca2 release and decreased sinoatrial node activity in a mouse model of catecholaminergic Polymorphic Ventricular Tachycardia
Circulation, 2012Co-Authors: Patricia Neco, Pietro Mesirca, Esther Zorio, Nian Liu, Silvia Priori, Carlo Napolitano, Sylvain Richard, Jean-pierre Benitah, Angelo G Torrente, Matteo E. MangoniAbstract:Background—Catecholaminergic Polymorphic Ventricular Tachycardia is characterized by stress-triggered syncope and sudden death. Patients with catecholaminergic Polymorphic Ventricular Tachycardia manifest sinoatrial node (SAN) dysfunction, the mechanisms of which remain unexplored. Methods and Results—We investigated SAN [Ca2+]i handling in mice carrying the catecholaminergic Polymorphic Ventricular Tachycardia–linked mutation of ryanodine receptor (RyR2R4496C) and their wild-type (WT) littermates. In vivo telemetric recordings showed impaired SAN automaticity in RyR2R4496C mice after isoproterenol injection, analogous to what was observed in catecholaminergic Polymorphic Ventricular Tachycardia patients after exercise. Pacemaker activity was explored by measuring spontaneous [Ca2+]i transients in SAN cells within the intact SAN by confocal microscopy. RyR2R4496C SAN presented significantly slower pacemaker activity and impaired chronotropic response under β-adrenergic stimulation, accompanied by the appe...
John M. Miller - One of the best experts on this subject based on the ideXlab platform.
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Polymorphic Ventricular Tachycardia induced by programmed stimulation response to procainamide
Journal of the American College of Cardiology, 1993Co-Authors: Alfred E Buxton, Mark E Josephson, Francis E Marchlinski, John M. MillerAbstract:Objectives. This study was designed to evaluate the effects of procainamide on Polymorphic Ventricular Tachycardia induced by programmed stimulation and to correlate the responses with heart disease, left Ventricular endocardial activation abnormalities and the signal-averaged electrocardiogram (ECG). Background. Polymorphic Ventricular Tachycardia is induced frequently during electrophysiologic studies. In many patients this response is an artifact of programmed stimulation; in others, it appears to be clinically relevant. Previous observations have suggested that in some patients type IA antiarrhythmic agents can change the response to programmed stimulation from Polymorphic to uniform Ventricular Tachycardia. Methods. Programmed right Ventricular stimulation was performed in the absence of antiarrhythmic drugs and after procainamide. Signal-averaged ECGs and left Ventricular maps were performed during sinus rhythm in the absence of antiarrhythmic drugs. Results. We evaluated 79 consecutive patients undergoing clinical electrophysiologic studies, in whom Polymorphic Ventricular Tachycardia was the only arrhythmia induced in the absence of antiarrhythmic drugs. After procainamide administration, uniform monomorphic Ventricular Tachycardia was induced in 24 patients (Group 1), inducible Polymorphic Ventricular Tachycardia persisted in 30 patients (Group 2) and no Ventricular Tachycardia could be induced in the remaining 25 patients (Group 3). Twenty-three (96%) of 24 patients developing uniform Ventricular Tachycardia after procainamide administration had coronary artery disease compared with 63% of Group 2 and 48% of Group 3 patients (p = 0.003). Left Ventricular aneurysms were also found more frequently (46%) in the patients developing uniform Ventricular Tachycardia after procainamide than in either Group 2 or Group 3 (13% and 0%, respectively, p < 0.008). Abnormalities of the signal-averaged ECG typically seen in patients with spontaneous reentrant sustained Ventricular Tachycardia were significantly more frequent in patients who developed inducible uniform Ventricular Tachycardia after procainamide than in those who did not. Similarly, patients developing uniform Ventricular Tachycardia after procainamide had more extensive abnormalities of left Ventricular endocardial activation revealed by catheter maps during sinus rhythm. Conclusions. The conversion of inducible Polymorphic Ventricular Tachycardia to uniform Ventricular Tachycardia after procainamide administration occurs almost exclusively in patients with coronary disease, previous myocardial infarction and abnormal left Ventricular function. This response may permit activation mapping of Tachycardias, allowing the appllcation of surgical or catheter ablation techniques that would otherwise not be possible in such patients.