Anatomical relevance of ablation to the pulmonary artery root: Clinical implications for characterizing the pulmonary sinus of Valsalva and coronary artery

Preventing Complications During Mapping and Ablation of Left Ventricular Summit Arrhythmias

The left ventricular summit is a site of origin for idiopathic ventricular arrhythmias. With advancements in mapping and ablation techniques, sites previously considered inaccessible can now be approached. Anatomical knowledge of the 3-dimensional landmarks of this space is important, as critical structures reside within its boundaries and are potentially liable to collateral injury during ablation. This article reviews reported complications from ablation of ventricular arrhythmias arising from the left ventricular summit and its vicinity and discusses the pros and cons of different ablation technique and the role of an individualized anatomical approach to reduce procedural related complications and improve outcomes.

The value of QRS onset of the outflow tract PVC in V1 and V2 leads recorded in fourth, third, and second intercostal spaces to differentiate main origins of premature ventricular contraction—A prospective cohort study

Background

Electrocardiography (ECG) is now proposed as a simple and cost‐effective tool to determine the location of arrhythmias before ablation. We aimed to examine the value of the QRS onset of outflow tract PVC in V1 and V2 leads recorded in fourth, third, and second intercostal spaces to differentiate two main origins for premature ventricular contraction (PVC) including right ventricular outflow tract (RVOT) and left ventricular outflow tract (LVOT).

Methods

In this prospective cohort study, a total of 58 patients were studied, from whom a surface ECG was obtained using V1 and V2 leads in the fourth, third, and second intercostal spaces. ECG and Electrophysiology studie (EPS) data were then recorded and compared to determine the sensitivity and specificity of QRS onset in locating arrhythmias. The reciever operating characterictic (ROC) curve analysis was applied to test diagnostic performance.

Results

Based on the time of PVC initiation in each of the V1 and V2 leads in the fourth intercostal space, if PVC is recorded earlier in the V1 lead, its source in 95.8% of the patients is RVOT and if PVC preceded the V2 lead, 70.59% of the patients had PVC from LVOT. Comparing of QRS onset in V1 and V2 leadsrecorded from third% and and second intercostal spaces had considerable sensitivity and specificity to determine the origin of the outflow tract PVC (81.82 and 94.12%, respectively)

Conclusion

Simultaneous recording of outflow tract PVCs from second third and fourth intercostal spaces and comparing their onset can determine the left and right outflow tract PVCs with high sensitivity and specificity.

Stepwise approach for visualization and reconstruction of pulmonary valve with intracardiac echocardiography

Ventricular tachycardia and premature ventricular complexes (PVCs) arising from right ventricular outflow tract (RVOT) are the most common type of ventricular arrhythmias (VAs) in patients without structural heart disease. Radiofrequency ablation is now the gold standard of treatment in this setting due to high efficacy rates and optimal safety profile. During the last few years, the pulmonary valve (PV) and the pulmonary artery (PA) have attracted much attention as reliable sites of origin of RVOT-type arrhythmias. In the mean while intracardiac echocardiogram (ICE) has undoubtedly improved our understanding of the cardiac anatomy. Aim of this paper is to provide an illustrated step-by-step guide on how to use ICE with the CARTOSOUND module to visualize and reconstruct 3D shell of the RV, the PV, as well of other contiguous anatomical structures (i.e., the aortic valve and coronary arteries) to perform aware and safe ablation in this region.