Electrocardiographic and Electrophysiologic Characteristics of Ventricular Extrasystoles Arising from the Aortomitral Continuity

Left ventricular outflow tract arrhythmias originating from the aortomitral continuity, the left coronary cusp, the superior basal septum, and the epicardial left ventricular summit display common electrocardiographic and electrophysiological features, probably due to the close proximity of those locations. Catheter ablation of these arrhythmias can be challenging. The case of a 68-year-old male with frequent premature ventricular extrasystoles arising from the aortomitral continuity of the basal left ventricle is described. The electrocardiographic and electrophysiologic characteristics of this arrhythmia are discussed

Current Ablation Strategies for Persistent and Long-Standing Persistent Atrial Fibrillation

Atrial fibrillation (AF) is associated with an increased risk of cardiac and overall mortality. Restoration and maintenance of sinus rhythm is of paramount importance if it can be accomplished without the use of antiarrhythmic drugs. Catheter ablation has evolved into a well-established treatment option for patients with symptomatic, drug-refractory AF. Ablation strategies which target the pulmonary veins are the cornerstone of AF ablation procedures, irrespective of the AF type. Ablation strategies in the setting of persistent and long-standing persistent AF are more complex. Many centers follow a stepwise ablation approach including pulmonary vein antral isolation as the initial step, electrogram-based ablation at sites exhibiting complex fractionated atrial electrograms, and linear lesions. Up to now, no single strategy is uniformly effective in patients with persistent and long-standing persistent AF. The present study reviewed the efficacy of the current ablation strategies for persistent and long-standing persistent AF

Catheter Ablation of Incessant Ventricular Tachycardia in a Patient With Coronary Artery Disease

A 67-year-old male with known coronary artery disease was referred to our hospital for catheter ablation of incessant ventricular tachycardia (VT). Transthoracic echocardiography revealed severe wall motion abnormalities of the left ventricle along with an apical aneurysm. Left ventricular voltage mapping showed a region with low voltage (<1.5 mV) at the left ventricular apex. Propagation mapping revealed a macro-reentry circuit around the apical aneurysm. Mid-diastolic potentials were recorded during the VT (Fig. 1, left panel, arrows), while entrainment mapping was excellent. The first radiofrequency energy application terminated the tachycardia. A circumferential lesion around the aneurysm was finally performed (Fig. 1, right panel, red dots). Ventricular tachycardia became non-inducible, and the patient is free from arrhythmic events during the last six months... (excerpt

Catheter Ablation of Right Ventricular Outflow Tract Ventricular Tachycardia

Α 57-year-old female with repetitive monomorphic ventricular tachycardia was referred for an electrophysiological study. ECG during sinus rhythm was normal. ECG during tachycardia revealed a left bundle branch block (LBBB) pattern with inferior axis suggestive of an outflow tract tachycardia (Fig. 1). Structural heart disease was excluded. Transthoracic echocardiography and coronary angiography were unremarkable. The tachycardia was easily induced by atrial pacing (Fig. 2). This was suggestive of cyclic adenosine monophosphate (c-AMP) triggered activity as the pathophysiological basis of the arrhythmia. Activation mapping revealed the earliest activity at the posteroseptal region of the right ventricular outflow tract. A systolic pre-potential was recorded in this area, which is rarely seen in these type of arrhythmias (Fig. 3)... (excerpt

Sinus node disease in subjects with type 1 ECG pattern of Brugada syndrome

AbstractBackgroundThe spectrum of phenotypes related to mutations of the SCN5A gene include Brugada syndrome (BS), long QT syndrome, progressive cardiac conduction defect, and sinus node disease (SND). The present study investigated the incidence of SND in subjects with type 1 electrocardiogram (ECG) pattern of BS.Methods and resultsThe study population consisted of 68 individuals (55 males, mean age 44.8±12.8 years) with spontaneous (n=27) or drug-induced (n=41) type 1 ECG pattern of BS. Twenty-eight subjects were symptomatic with a history of syncope (41.2%). SND was observed in 6 symptomatic subjects (8.8%), and was mainly attributed to sino-atrial block with sinus pauses. Two patients were initially diagnosed with SND, and received a pacemaker. Patients with SND displayed an increased P-wave duration in leads II and V2, PR interval in leads II and V2, QRS duration in leads II and V2, and increased QTc interval in lead V2 (p<0.05). AH and HV intervals as well as corrected sinus node recovery time (cSNRT) were significantly prolonged in subjects with SND (p<0.05). During a mean follow-up period of 5.0±3.6 years, five subjects with a history of syncope suffered appropriate implantable cardioverter defibrillator (ICD) discharges due to ventricular arrhythmias (7.4%). None of those diagnosed with SND suffered syncope or ICD therapies.ConclusionSND is not an uncommon finding in subjects with type 1 ECG pattern of BS. The occurrence of SND in relatively young patients may deserve meticulous investigation including sodium channel blocking test

Modern mapping and ablation of idiopathic outflow tract ventricular arrhythmias

Outflow tract (OT) premature ventricular complexes (PVCs) are being recognized as a common and often troubling, clinical electrocardiographic finding. The OT areas consist of the Right Ventricular Outflow Tract (RVOT), the Left Ventricular Outflow Tract (LVOT), the Aortomitral Continuity (AMC), the aortic cusps and the Left Ventricular (LV) summit. By definition, all OT PVCs will exhibit an inferior QRS axis, defined as positive net forces in leads II, III and aVF. Activation mapping using the contemporary 3D mapping systems followed by pace mapping is the cornerstone strategy of every ablation procedure in these patients. In this mini review we discuss in brief all the modern mapping and ablation modalities for successful elimination of OT PVCs, along with the potential advantages and disadvantages of each ablation technique