case_images: PMC10198291_01
case_images: Stepwise fluoroscopic imaging in the left anterior oblique view showing successful implantation of a cardiac resynchronization therapy defibrillator in a patient with a persistent left superior vena cava. A: Guidewires in the persistent left superior vena cava. B: Cororonary sinus angiogram showing a large coronary sinus with a small acute angulated posterolateral branch. C: Attempted antegrade placement of the left ventricular lead into the branch. D: Selective angiogram showing a well-developed posterolateral branch with collateral connection (white arrows) toward the middle cardiac vein. E: Hi-Torque Whisper  and Pilot  guidewires (Abbott) inside the posterolateral branch. F: Selective engagement of the middle cardiac vein with both outer and inner catheters and the guidewire advanced to the right atrium via the collaterals and snared in the right atrium. G: Left ventricular lead advanced over the snared guidewire. H: Final lead positions. Abbreviations: AAPL, acute angulated posterolateral branch; CS, coronary sinus; IC, inner catheter; LV, left ventricular; MCV, middle cardiac vein; OC, outer catheter; PLSVC, persistent left superior vena cava; Sn, snare; WDPL, well-developed posterolateral branch.
case_images: icrm-14-5322-g001.jpg
case_images: PMC10198291_01_icrm-14-5322-g001.jpg
case_images: fg001
case_images: Venography confirmed a PLSVC with no antegrade flow into the SVC (Figure 1A). We introduced a CS delivery outer guide catheter (CPS Direct SL II 115; Abbott, Chicago, IL, USA), and contrast injection inside the CS revealed a posterolateral branch with acute angulation (Figure 1B). This branch was selectively cannulated with a subselective inner catheter (CPS AIM Universal; Abbott), and an angiogram revealed a relatively well-developed posterolateral branch (WDPL) with collaterals toward the middle cardiac vein (MCV) (Figures 1C and 1D). Despite several attempts, the LV lead could not be advanced due to an unfavorable angle (Figure 1E). Subsequently, the MCV with well-developed collaterals was engaged with a vertebral vein selector sheath (Merit Medical, South Jordan, UT, USA) toward the posterolateral branch (Figure 1F). Finally, the guidewire was advanced into the RA through the collaterals (initially WDPL, then acutely angulated posterolateral branch) via the posterolateral branch, and the distal end of the wire was left in the high RA (Figure 1G). The LV lead was tracked into its desired position with the aid of a veno-venous loop (Figure 1H).