Identification of lateral cardiac veins for cardiac resynchronization therapy.

We present a 59-year-old patient with long standing chronic heart failure with a previous single chamber implantable defibrillator referred for upgrade to resynchronization therapy. Initial images of the CS revealed no lateral veins (Figure 1). The catheter was withdrawn to the ostium and contrast injection proximally revealed the presence of a separate CS (Figures 2 and 3). Manipulation of the catheter eventually allowed cannulation of this vessel, imaging of the lateral branches (Figure 4), and successful lateral LV lead placement.