case_images: PMC9995897_01
case_images: (A) 12-lead ECG at admission showing AF with rapid ventricular response despite rate-control therapy. (B) 12-lead ECG showing phases of AF with slow ventricular response with ventricular pacing at the lower rate (ICD in VVI 30). Note the morphology of the paced QRS with RBBB pattern, superior axis with R pattern in aVR. AF, atrial fibrillation; ICD, implantable cardioverter defibrillator; RBBB, right bundle branch block.
case_images: fcvm-10-1088697-g001.jpg
case_images: PMC9995897_01_fcvm-10-1088697-g001.jpg
case_images: F1
case_images: A 12-lead ECG showed AF with rapid ventricular response and normal QRS duration (90 ms) (Figure 1A). Unfortunately, a 12-lead ECG during ventricular pacing was not recorded before admission, however it was obtained during hospital stay from continuous ECG monitoring (Figure 1B).
case_images: PA (A) and LL (B) chest x-ray of the patient showing inadvertent lead placement in the posterior branch of the coronary sinus. PA, posteroanterior; LL, laterolateral.
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case_images: PMC9995897_01_fcvm-10-1088697-g002.jpg
case_images: F2
case_images: A chest X-ray (CXR) was obtained at admission (Figure 2).
case_images: (Superior row) PA (A), RAO 30  (B), and LAO 45  (C) fluoroscopic views of the previously implanted single chamber cardioverter defibrillator with a single coil passive fixation defibrillation lead. (Inferior row) PA (D), RAO 30  (E), and LAO 45  (F) fluoroscopic views after lead extraction and the reimplantation of a new single-coil active fixation defibrillation lead on the mid portion of the interventricular septum and a coronary sinus quadripolar passive fixation lead for cardiac resynchronization therapy. PA, posteroanterior; RAO, right anterior oblique; LAO, left anterior oblique.
case_images: fcvm-10-1088697-g003.jpg
case_images: PMC9995897_01_fcvm-10-1088697-g003.jpg
case_images: F3
case_images: At the same time, we performed implantation of a CRT device with a single-coil active fixation defibrillation lead placed in the mid-ventricular septum, and a quadripolar passive fixation lead in coronary sinus posterior branch (the only available, Figure 3).