Search results for "Supraventricular arrhythmia"
showing 8 items of 8 documents
Antivitamin K Drugs in Stroke Prevention
2014
Among the different subtypes of ischaemic strokes, almost 20 % are of cardiac origin. Different are the causes of cardioembolic stroke, but the most common is the atrial fibrillation, a supraventricular arrhythmia. Appropriate use of antiplatelet drugs and anticoagulants after transient ischaemic attack (TIA) or ischaemic stroke depends on whether the underlying cause is cardioembolic or of presumed arterial origin. Adequate antiplatelet therapy is recommended for secondary prevention after cerebral ischaemia of presumed arterial origin, whether for patients with TIA and ischaemic stroke of cardiac origin, mainly due to atrial fibrillation. Vitamin K antagonists (VKAs) are highly effective …
Cardiac arrhythmias as correlated with the circadian rhythm of arterial pressure in hypertensive subjects with and without left ventricular hypertrop…
1990
To evaluate the relationship among supraventricular and ventricular arrhythmias with blood pressure and heart rate (HR) values, we studied 2 groups of 20 hypertensive men with (group I) and without (group II) left ventricular hypertrophy. Ambulatory electrocardiographic tracings were recorded continuously, together with ambulatory arterial pressure. Systolic (SBP) and diastolic (DBP) blood pressure values measured over 24 h showed no difference between the two groups, but we found greater variability in SBP in group I. The incidence of ventricular and supraventricular arrhythmias was significantly higher in patients of group I; moreover, we found a strong correlation between the incidence o…
Mechanism of Sinoatrial Node Dysfunction in a RyR 2 R420Q Mouse Model Ofcatecholaminergic Polymorphic Ventricular Tachycardia
2017
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a genetic disease characterized by stress-induced syncope and/or sudden death in young individuals with structurally normal heart. More than 150 mutations located in the cardiac Ca2+ release channel (type-2 ryanodine receptor, RyR2) gene are related to CPVT. Besides ventricular tachycardia (VT) under stress, sinoatrial node (SAN) dysfunction is frequently observed in CPVT patients. However, the cellular mechanisms remain underexplored. We created a KI mice model bearing a mutation in the N-terminal portion of the RyR2 found in a CPVT family, RyR2(R420Q). ECGs were recorded in KI and WT littermates in resting condition and after…
Intracardiac Cardioversion for Ablation of the Atrioventricular Conduction System in Patients with Drug Resistant Atrial Flutter
1983
The technique of intracardiac cardioversion for the ablation of the atrioventricular conduction system was used in three male patients (65, 53 and 57 years of age) with atrial flutter unresponsive to medical management. In the first patient a DC current of 80 J was applied while the other patients required 300 and 400 J respectively. In the first patient a transient third degree AVblock was induced enabling the ventricular rate to be easily controlled with drugs. This patient died 5 months later of resistant congestive heart failure. Autopsy revealed no gross evidence of myocardial damage in the tricuspid valve area or in the interventricular septum. In the other two patients a permanent th…
“Three-level shock” in ablation-refractory paroxysmal atrial fibrillation
1987
His-bundle ablation is a very effective method to control drug-refractory supraventricular arrhythmias. We present a 69-year-old woman with paroxysmal atrial fibrillation, in whom several attempts of unipolar and bipolar His-bundle ablation were ineffective. Ultimately a stable 2/1 atrioventricular block was induced when three successive shocks of 400 W were applied. The first shock was given in that position with the largest His-potential deflection. The other two shocks were applied at catheter positions more distal and more proximal from the first one, respectively. We suppose that the initial lack of success was due to an atypical atrioventricular junction anatomy.
Supraventricular arrhythmias in noncompaction of left ventricle: Is this a frequent complication?
2008
Background: Isolated left ventricular noncompaction is the result of incomplete myocardial morphogenesis, leading to persistence of the embryonic myocardium. The condition is recognised by an excessively prominent trabecular meshwork and deep intertrabecular recesses of the left ventricle. Whether these intertrabecular recesses are a favorable substrate for supraventricular arrhythmias is unclear, even if the incidence of chronic heart failure seems to be high. Results: We evaluated a continuous series of 238 patients affected by noncompaction. In 4 cases the patients reported palpitations and in 4 an episode of syncope. Periodic holter monitoring was performed every 6 months for 4 years. O…
Arrhythmieprofil und Herzfrequenz bei Hyperthyreose
2008
Arrhythmia profiles and heart rates, obtained by 24-hour ECG monitoring, were analysed in 48 patients with hyperthyroidism before (T3 level: 331 +/- 108 ng/100 ml, heart rate: 95 +/- 13/min), during (T3 level: 202 +/- 98 ng/100 ml, heart rate: 85 +/- 11/min) and after (T3 level: 149 +/- 41 ng/100 ml, heart rate: 79 +/- 9/min) antithyroid treatment. 50 persons in whom organic heart disease has been excluded by invasive and noninvasive tests served as controls. Only 6% of patients had repetitive ventricular arrhythmias (Lown group IV) before treatment (controls: 4%; P greater than 0.05). Supraventricular extrasystoles were common both before and after treatment (P less than 0.001), especially…
Morphometry and comparative histology of sinus and atrioventricular nodes in humans and pigs and their relevance in the prevention of nodal arrhythmi…
2019
The cardiac conduction system is a network structure that allows the initiation and fast propagation of electrical impulses that trigger the electrical depolarization of the myocardial tissue. The purpose of this work is to study the histological and morphometric characteristics of the different components of the sinus and atrioventricular nodes in humans and pigs and their relationship with supraventricular arrhythmias. In this study, we describe the morphometry of the sinus and atrioventricular nodes of 10 adult humans and 10 pig hearts. A computerized morphometric study has been carried out, where we determined the number of cells that compose the nodes as well as different parameters re…