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.