title: The insufficiency of left anterior oblique and the usefulness of right anterior oblique projection for correct localization of a computed tomography-verified right ventricular lead into the midseptum.
abstract: BACKGROUND
  The aim of the study was to verify the correct anchoring location for the tip of the right ventricular lead using cardiac computed tomography and to assess the best fluoroscopic and ECG criteria associated with the correct location of the electrode into the midseptum.
  
  
  RESULTS
  Patients indicated to pacemaker implantation were prospectively enrolled. The right ventricular lead was implanted into the midseptum according to standard criteria in left anterior oblique 40 view. The cardiac shadow on the right anterior oblique 30 was divided into 4 quadrants perpendicular to the lateral cardiac silhouette and the position of the lead tip was analyzed. The exact position of the lead tip was assessed using computed tomography. Of 51 patients, the right ventricular lead was anchored midseptum in 21 (41.2%; MS group). In 30 patients (58.8%; non-MS group), the lead was anchored in the adjacent anterior wall. The angle between the lead and horizontal axis on the left anterior oblique was similar in both groups. The non-MS group was associated with shorter distances between the tip and the cardiac contours in the right anterior oblique 30 (96.7% of leads in the non-MS group were in the outer quadrant versus 9.6% in the MS group; P<0.001). The presence of the lead in the middle or inferior quadrants was independently associated with correct midseptum placement with positive predictive value of 94.7%.
  
  
  CONCLUSIONS
  Despite the optimal shape of the left anterior oblique, substantial numbers of leads were not anchored in the midseptum. Knowing the right anterior oblique 30 lead position can ensure proper midseptal placement.
authors.affiliation: Cardiocenter, Department of Cardiology, 3rd Medical School, Charles University and University Hospital Kralovske Vinohrady, Prague, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Osmancik
authors.forename: Petr
authors.initials: P
authors.lastname: Stros
authors.forename: Dalibor
authors.initials: D
authors.lastname: Herman
authors.forename: Karol
authors.initials: K
authors.lastname: Curila
authors.forename: Robert
authors.initials: R
authors.lastname: Petr
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial; D016009:Chi-Square Distribution; D004562:Electrocardiography; D004867:Equipment Design; D005260:Female; D005471:Fluoroscopy; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D016015:Logistic Models; D008297:Male; D061330:Multidetector Computed Tomography; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D054088:Ventricular Septum / Q000000981:diagnostic imaging*
keywords: cardiac pacing; fluoroscopy; pacemaker implantation; right ventricular apex; ventricular septum