Case Report:
A 40-year-old female presented with symptomatic palpitations and was
found to have 8% burden of monomorphic PVCs of inferior axis left
bundle branch block (LBBB) morphology (Figure 1A ) despite
titration of metoprolol and flecainide doses. During workup for PVC
ablation, cardiac computed tomography (CT) revealed an anomalous RCA
originating from the left sinus of Valsalva with an interarterial,
intramural course (Figure 1B ). Given the intramural course, she
was referred for surgical unroofing of the anomalous
RCA7 and concomitant surgical cryoablation of the PVC.
A novel peri-operative surgical PVC ablation workflow was designed
utilizing a non-invasive 12-lead ECG based mapping system (vMap, Vektor
Medical Inc, Carlsbad, CA). In the outpatient clinic, the patient’s PVCs
were captured using a standard 12-lead ECG acquisition system (Muse, GE
Medical) and digitized using custom software. The ECG data file was
imported into the computational ECG mapping system. Patient
characteristics (absence of scar or left ventricle dilation) were
recorded, and the PVC exit site was localized to the septal right
ventricular outflow tract (RVOT) underneath the pulmonic valve, near the
course of the anomalous RCA. The site of origin was visualized on a 3D
model (Figure 1C ) within 36 seconds of total mapping time.
Subsequently, the patient was placed under general anesthesia and
underwent sternotomy. She was initiated on cardiopulmonary bypass, and
the heart was arrested. An incision was made in the pulmonary artery,
and 3 cryoablation lesions using a cryoablation probe of 90 second
durations to -50° Celsius were placed at the PVC exit site localized to
the septal RVOT (Figure 1D ). The pulmonary artery incision was
then sutured. Coronary artery unroofing of the intramural RCA was
performed, after which the heart was re-perfused, and the patient was
weaned off bypass uneventfully.
Post-operatively, the patient recovered without any complications. There
were no PVCs on telemetry, and she was discharged from the hospital in 4
days. Her palpitations and PVCs were eliminated durably, with event
monitors showing <1% PVC burden at 2-year follow-up.