Validation of conventional fluoroscopic and ECG criteria for right ventricular pacemaker lead position using cardiac computed tomography.
BACKGROUND
It is hypothesized that pacing the right ventricular (RV) septum is associated with less deleterious outcomes than RV apical pacing. Our aim was to validate fluoroscopic and electrocardiography (ECG) criteria for describing pacemaker and implantable cardioverter defibrillator RV "septal" lead position against the proposed gold standard: cardiac computed tomography (CT).


METHODS
Using the conventional fluoroscopic criteria, we intended to place RV nonapical leads on the interventricular septum. Lead positions were later retrospectively analyzed with CT and correlated with ECGs and fluoroscopic projections: posterior-anterior, 40° left anterior oblique (LAO), 40° right anterior oblique (RAO), and left lateral.


RESULTS
Only 21% (nine of 35) of presumed "septal" RV nonapical leads using the conventional fluoroscopic criteria were on the true septum. A schema developed to define septal position in the RAO fluoroscopic view had high agreement with CT images. ECG criteria had only fair to moderate agreement with CT. The paced QRS duration was significantly longer (P < 0.001) with RV apical pacing (176 ± 10.7 ms), compared to RV nonapical pacing (144.5 ± 14.3 ms).


CONCLUSIONS
Using the conventional fluoroscopic criteria, only a minority of RV leads were implanted on the true RV septum. Instead, aiming for the middle of the cardiac silhouette in the RAO fluoroscopic view, confirming rightward orientation in the LAO view, and having a paced QRS duration <140 ms may allow the implanting cardiologist a simple, more accurate method to achieve true RV septal lead positioning.
Department of Cardiology, Royal Melbourne Hospital, Parkville, Victoria, Australia; The Department of Medicine, University of Melbourne, Victoria, Australia.
Benjamin J
BJ
Pang
Subodh B
SB
Joshi
Elaine H
EH
Lui
Mark A
MA
Tacey
Liang-Han
LH
Ling
Jeff
J
Alison
Sujith K
SK
Seneviratne
James D
JD
Cameron
Harry G
HG
Mond
D001315:Australia; D004562:Electrocardiography / Q000379:methods*; D004567:Electrodes, Implanted; D005471:Fluoroscopy / Q000379:methods*; D006346:Heart Septum / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D010138:Pacemaker, Artificial; D019919:Prosthesis Implantation / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
computer tomography; fluoroscopy; pacing and ICD lead implantation; right ventricular septum