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Remote magnetic navigation (RMN) presents a promising approach for catheter ablation in complex arrhythmias. This study aims to offer additional insights into the feasibility, safety, and efficacy of RMN for catheter ablation of epicardial atrial and ventricular arrhythmias in patients without structural heart disease. We present a case series of three patients (39-year-old female, 28-year-old female, and 17-year-old male) referred to our institute for epicardial ablation following unsuccessful endocardial procedures. The first patient exhibited approximately 40,000 monomorphic premature ventricular complexes (PVCs) in a 24-hour Holter recording, while the second patient experienced incessant left ventricular tachycardia (VT). In both cases, the QRS morphology indicated an epicardial origin of the arrhythmia. The third patient suffered from incessant atrial tachycardia (AT) originating from the distal portion of the vein of Marshall (VOM). Epicardial 3D electroanatomic mapping and ablation with RMN were performed with ease and minimal fluoroscopy usage. Coronary angiogram visualization on the RMN screen provided real-time information on the catheter tip's position relative to the coronary arteries. In all cases, the earliest signals were recorded epicardially, and unipolar recordings displayed sharp negative deflections at the sites of successful ablation. In the first patient, pace mapping was superior in the epicardium compared to the endocardium, and PVCs were eradicated by epicardial ablation. In the second patient, epicardial ablation immediately terminated the VT. In the third patient, epicardial ablation at the site exhibiting a distinct VOM potential promptly terminated the AT. No perioperative complications were observed, and all patients remained asymptomatic and free of arrhythmias during long-term follow-up. Our findings suggest that RMN is a feasible, effective, and safe approach for epicardial ablation of left ventricular outflow tract PVCs and VT, as well as atrial tachycardia originating from the VOM. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the antiarrhythmic mechanisms of magnesium (Mg). The 12 patients who were selected for the study were given 12 mmol Mg sulphate followed by an infusion of 8 mmol/h. Ventricular effective refractory period (VERP). monophasic action potential duration at 50% and 90% repolarization during spontaneous rhythm (MAPD50, MAPD90) and atrial pacing at a cycle length of 600 ms (MAPD(50)600, MAPD(90)600) were measured before and after the intervention. Plasma magnesium concentration rose from 0.83 +/- 0.05 to 1.85 +/- 0.24 mmol/l (p < 0.001). Shortening of MAPD(50) (250 +/- 45 vs 240 +/- 46 ms; p < 0.05), MAPD(90) (294 +/- 42 vs 283 +/- 41 ms; p < 0.05) and shortening of sinus cycle length (SCL) (783 +/- 153 vs 742 +/- 160 ms; p < 0.01) were detected. During controlled cycle length, magnesium decreased MAPD(50)600 (230 +/- 28 vs 221 +/- 28 ms; p < 0.01), MAPD(90)600 (274 +/- 25 vs 261 +/- 29 ms; p < 0.01) and VERP (247 +/- 25 vs 241 +/- 21 ms: p < 0.05). QRS duration, QT interval and blood pressure remained unchanged. The change in SCL correlated with the change in MAPD(50) (r = 0.58; p < 0.05) and MAPD(90) (r = 0.55; p = 0.06 ) but not with MAPD(50)600, MAPD(90)600 or VERP. Magnesium acutely shortens ventricular monophasic action potential duration and refractoriness. This effect is partly mediated by mechanisms that increase heart rate. The reductions might bring salutary effects in arrhythmias evoked by prolonged repolarization. [ABSTRACT FROM AUTHOR]

Loss of consciousness i.e. syncope is a common cause of getting to emergency call service. We describe two patients, in whom fainting was caused by reflexogenic syncope. The diagnosis is quickly solved if there is patience to review the patient history as thoroughly as possible. Registration of the conventional 12-lead electrocardiography and clinical examination usually suffice as basic investigations, without the need for expensive equipment. Careful scrutiny of the medical history will not only reveal the cause of fainting but also the predisposing factors, whereby recurrence of the event can easily be avoided by recognizing a threatening situation early enough.

The prevalence and incidence of atrial fibrillation (AF) are increasing rapidly. Key recommendations in management of AF include prompt administration of oral anticoagulation to all patients with elevated risk of thromboembolic complications, proper use of antiarrhythmic drugs and invasive therapies in highly symptomatic patients and adequate rate control in patients with permanent AF. The selection between warfarin and the novel oral anticoagulants (apixaban, dabigatran, rivaroxaban) is based on careful evaluation of the benefits and disadvantages of the drugs in a given patient.

Sudden deaths occurring during exercise are rare and are most commonly due to cardiac arrest. It is most commonly underlain by symptomless cardiomyopathy or coronary artery disease. Preventive work comes up against a diagnostic problem in distinguishing adaptational changes of the athletic heart from a heart disorder. To reveal the danger of cardiac arrest and reduce human tragedies international sports organizations and cardiologic expert groups recommend screening of cardiac disorders among competing athletes.

Catheter ablation is currently the preferred treatment for various arrhythmias. Radiofrequency ablation has been shown to be efficacious and safe. Cryoablation provides better ablation catheter stability and reduces the risk of an inadvertent atrioventricular (AV) block when treating arrhythmia substrates near the normal conduction system. In our own seven year experience of cryoablation in 157 patients no serious complications occurred. In children and young patients, cryoablation has become the preferred method for AV nodal re-entrant tachycardia. Cryoablation is preferable for all tachycardia substrates near the normal conduction system in children, teenagers and adults.

Referral to electrophysiological testing is based on anamnesis and arrhythmic ECG recording. In this study, flexible thin diagnostic catheters are introduced into the patient's heart and by pacing the heart from the atria and ventricles the properties of the heart's intrinsic conducting pathways are determined, as well as whether the patient has potentially treatable structures (substrates) causing arrhythmias. The aim of the study is to initiate an arrhythmia similar to that having caused the patient to seek medical examination. The arrhythmia can often be simultaneously treated with catether ablation.