Conclusions
A subgroup of patients with frequent (20% <) MA-PVCs demonstrated a significantly enlarged LVDd and LVDs, reduced LVEF, deteriorated NYHA functional class, and elevated serum BNP concentration as compared to the subgroup with rare (≤ 20%) MA-PVCs. Furthermore, the RFCA of these arrhythmias was associated with the normalization of these abnormalities without any adverse effects. These findings suggest thatsimilar to RVOT-PVCs, MA-PVCs may be a possible cause of LV dysfunction and/or heart failure, as previously reported1. Thus, the physicians should be aware of this condition when examining patients with LV dilation and/or a reduced LVEF in the presence of frequent MA-PVCs because it may be at least one important risk factor for the progression of LV dysfunction and heart failure.
In addition, initially performing a trans-interatrial septal approach and using a steerable introducer to gain a stronger support and contact force of the ablation catheter, performing detailed electro-anatomical mapping using by a circular mapping catheter or high density mapping catheter to detect more precise earliest activation sites of the target MA-PVCs, and using open irrigated ablation catheters to obtain a stable lesion creation, may be one of the important procedures to achieve a high successful rate of the RFCA of MA-PVCs. Interestingly, because a successful RFCA was achieved for the MA-PVCs from not only the ventricular side of the MA (Figure 3BC) or coronary sinus (Figure 3E) but also from the LA side of the MA (Figure 3D), it may be necessary to understand the cardiac anatomy and try to ablate those PVCs from various approach sites, especially using a trans-interatrial septal approach initially may be helpful. Because these PVCs are often drug-refractory, RFCA may be considered as the first choice of therapy in those patients.