Imaging and Right Ventricular Pacing Lead Position: A Comparison of CT, MRI, and Echocardiography

• Published in: Pacing and clinical electrophysiology Vol. 39; no. 4; pp. 382 - 392
• Main Authors: MOORE, PETER, COUCHER, JOHN, NGAI, STANLEY, STANTON, TONY, WAHI, SUDHIR, GOULD, PAUL, BOOTH, CAMERON, PRATAP, JIT, KAYE, GERALD
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01-04-2016
• Subjects: echocardiography; Echocardiography - methods; electrocardiogram; Electrodes, Implanted; Female; Heart Ventricles - diagnostic imaging; Heart Ventricles - surgery; Humans; imaging; Magnetic Resonance Imaging - methods; Male; Middle Aged; Pacemaker, Artificial; pacing; Prosthesis Implantation - methods; Reproducibility of Results; Sensitivity and Specificity; Single-Blind Method; Surgery, Computer-Assisted - methods; Tomography, X-Ray Computed - methods; electrocardiogram; pacing; imaging; echocardiography
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/pace.12817

Background
Right ventricular nonapical (RVNA) pacing may reduce the risk of heart failure. Fluoroscopy is the standard approach to determine lead tip position, but is inaccurate. We compared cardiac computed tomography (CT), magnetic resonance imaging (MRI), two‐dimensional and three‐dimensional transthoracic echocardiography (TTE), and chest x‐ray (CXR) to assess which provides the optimal assessment of right ventricular (RV) lead tip position.
Methods
Eighteen patients with MRI‐conditional pacemakers (10 RVNA and eight apical [RVA] leads) underwent contrast CT, MRI, TTE, and a standard postimplant posteroanterior and lateral CXR. To compare images, the RV was arbitrarily partitioned into three long‐axis segments (right ventricular outflow tract, middle, and apex), and two short‐axis segments (septal and nonseptal). Agreement between modalities was assessed.
Results
RV lead tip position was identified in all patients on CT, TTE, and CXR, but was not identified in seven (39%) patients on MRI due to device‐related artifact. Of 10 leads deemed to be nonapical/septal during implant, 70% were identified as nonapical on CXR, 60% on CT, 60% on MRI, and 80% on TTE. On CT imaging only 10% were truly septal, 20% on MRI, 30% on CXR, and 80% on TTE. Agreement was better between modalities when assessing position of the designated RVA leads.
Conclusion
During implant leads intended for the septum are not confirmed as such on subsequent imaging, and marked heterogeneity is apparent between modalities. MRI is limited by artifact, and discrepancy exists between TTE and CT in identifying septal lead position. CT gave the clearest definition of lead tip position.