Electrocardiographic features, mapping and ablation of idiopathic outflow tract ventricular arrhythmias

Abstract

Purpose Idiopathic outflow tract ventricular arrhythmias are ventricular tachycardias or premature ventricular contractions presumably not related to myocardial scar or disorders of ion channels. These arrhythmias have focal origin and display characteristic electrocardiographic features. The purpose of this article is to review the state of the art of diagnosis and treatment of idiopathic outflow tract ventricular arrhythmias. Methods We systematically reviewed scientific literature about idiopathic outflow tract ventricular arrhythmias selecting the most relevant papers on this topic. Results The right ventricle outflow tract is the most common site of origin for outflow tract ventricular arrhythmias, but also left ventricle outflow tract can harbour these arrhythmias. Outflow tract ventricular arrhythmias are generally benign and may require treatment if they are symptomatic, incessant or give rise to cardiomyopathy. Radiofrequency catheter ablation is an effective and safe therapeutic strategy. A successful procedure requires a thorough preoperative analysis of the 12-lead electrocardiogram of the spontaneous arrhythmia combined with a detailed electroanatomical mapping and intracardiac echocardiography. Conclusions Idiopathic outflow tract arrhythmias are frequent in daily clinical practice and can be successfully eliminated through discrete radiofrequency catheter ablation with low rates of complications. Keywords Idiopathic ventricular arrhythmias. Ventricular outflow tract. Catheter ablation. Electrocardiogram Abbreviations OT outflow tract VA ventricular arrhythmia RVOT right ventricle outflow tract LVOT left ventricle outflow tract RFCA radiofrequency catheter ablation PVC premature ventricular contraction LBBB left bundle branch block RBBB right bundle branch block ECG electrocardiogram * Carlo Lavalle

Flecainide in Ventricular Arrhythmias: From Old Myths to New Perspectives

“…During IVAs haemodynamic impairment or serious symptoms are unusual, but patients can have palpitations, atypical chest pain or LV dysfunction. IVAs are distinguished by whether or not they originate from the outflow tracts and display specific electrocardiographic features [29].…”

“…The origins of RVOT and LVOT can be distinguished on the ECG by the precordial R-wave transition from a predominate S wave to a predominate R wave (rS to Rs). Transitions before V3 indicate an LVOT source and after V3 indicate an RVOT source [29][30][31][32], as seen in Figure 1. When LBBB QRS morphology is observed and the precordial transition occurs at V3, comparison to the patient's sinus rhythm precordial transition can be useful: a V2 transition ratio ≥ 0.60 suggests LVOT origin with high sensitivity and specificity [33,34].…”

Poorly Differentiated Breast Adenocarcinoma as a Rare Cause of Right Ventricular Outflow Tract Compression: Case Report and Review of the Literature

“…Additionally, review of the patient's CT chest revealed osseous involvement of the sternum and of the left aspect of the mediastinum, causing extrinsic compression of the RVOT, with elevated right heart pressures seen on echocardiography. The RVOT is a known arrhythmogenic source of many ventricular arrhythmias, such as premature ventricular contractions, ventricular bigeminy, and sustained ventricular tachyarrhythmias, 5,6 and a site of involvement identified in early case reports with extrinsic compression from anterior chest involvement from lymphoma and new diagnosis of ventricular arrhythmia. 7,8 In patients with advanced tumor burden and either extrinsic or intrinsic cardiac involvement, there are no current consensus guidelines for selecting an ideal candidate for transcatheter or minimally invasive management, though it seems a reasonable consideration for patients who may receive a direct palliative benefit from intervention, or in those with a stable tumor burden and related cardiovascular symptoms.…”

“…Additionally, review of the patient’s CT chest revealed osseous involvement of the sternum and of the left aspect of the mediastinum, causing extrinsic compression of the RVOT, with elevated right heart pressures seen on echocardiography. The RVOT is a known arrhythmogenic source of many ventricular arrhythmias, such as premature ventricular contractions, ventricular bigeminy, and sustained ventricular tachyarrhythmias, 5,6 and a site of involvement identified in early case reports with extrinsic compression from anterior chest involvement from lymphoma and new diagnosis of ventricular arrhythmia. 7,8…”

Myocardial Tissue Characterization in Heart Failure with Preserved Ejection Fraction: From Histopathology and Cardiac Magnetic Resonance Findings to Therapeutic Targets

“…From the clinical point of view, the myocardial fibrosis spatial distribution and temporal onset may play a prognostic role, being involved in systolic and diastolic dysfunction, as well as arrythmias [ 37 , 38 , 39 , 40 , 41 , 42 ]. In HF patients, the myocardial fibrosis may vary in term of spread and entity, defining a personalized and specific fibrosis distribution pattern.…”