A Case of Ventricular Premature Contractions With Multiple Morphologies Reproduced by a Single Ventricular
Naoyuki Miwa1, Tadanori Nakata1, Satoshi Hara1
1Department of Cardiology, Tsuchiura Kyodo General Hospital, Ibaraki, Japan.
Introduction:
A 22-year-old male with no cardiovascular history presented with frequent symptomatic ventricular premature contractions (VPCs) with multiple QRS morphologies despite bisoprolol treatment.
Results:
The coupling intervals progressively increased from VPC1 to VPC3, and VPC2 was the most frequent. The earliest activation site was identified at the left-right coronary cusp junction. Single ventricular extrastimuli with variable coupling intervals from this site successfully reproduced QRS morphologies identical to VPC1-3.
Conclusion:
This case illustrated how a single focus VPC could exhibit multiform morphology due to varying fusion with intrinsic conduction and the importance of coupling interval-matched extrastimuli in identifying the origin.
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