Case Report
A 55-year-old man presented with heart failure due to dilated hypertrophic cardiomyopathy. His electrocardiogram revealed a right bundle branch block with a wide QRS complex (QRS length=208 ms) and first-degree atrioventricular block (PR length=316 ms). He had undergone catheter ablation four times for atrial fibrillation / tachycardia and had taken diuretics and beta-blockers for the same. Despite rhythm control and adequate medication therapy, he still had dyspnea and refractory leg edema. To manage the patient’s uncontrolled heart failure, we decided to implant a CRT pacemaker. Written informed consent was obtained from the patient before the CRT pacemaker implantation.
Angiography of the coronary sinus was used to determine whether the posterolateral vein was suitable to deploy the LV lead. We selected the active fixation LV pacing lead (Attain Stability Quad 4798, Medtronic, Dublin, Ireland) for implantation, which is a quadripolar LV lead with an active fixation helix assembly designed to position the lead in the coronary sinus.3 A large-curve-type coronary sinus cannulation catheter (Attain Command + SureValve Integrated Valve, Medtronic, Dublin, Ireland) was used to deploy the lead using a standard over-the-wire technique, which involved advancing the pacing lead over the wire into the desired location, with the distal electrodes positioned in the mid-LV segment. However, the lead did not advance smoothly as the target vessel was tortuous (Figure 1). Moreover, the pacing threshold was high, despite the deep insertion of the LV lead. To overcome this, we used an extra support guidewire (GRAND SLAM, Asahi Intecc, Aichi, Japan) and a 135-degree subselection catheter (Attain Select II + SureValve sub-selection catheter, Medtronic); however, we were unable to advance the LV lead further.
Subsequently, we attempted to engage the cannulation catheter deep within the coronary sinus as this could provide better support to pass the LV lead through the tortuous vessel. To achieve this, we applied the anchor technique, which is already reported as a technique for obtaining superior guiding catheter support during the advancement of a balloon catheter in coronary angioplasty4 Once the lead was placed in the deepest position, it was rotated clockwise to achieve active temporary fixation of the lead. Next, we inserted and advanced the cannulation catheter while gently pulling the temporarily fixed LV lead. As the LV lead was fixed, it did not fall out of position despite being pulled, and we were able to advance the cannulation catheter deeper. As a result, superior cannulation catheter support was obtained without the LV lead falling out of position. Following this, the LV lead was rotated counterclockwise, and the fixation mechanism was released from the vein wall. Further, the lead was advanced to the middle lateral position, and refixation was performed. Using this method, the LV lead was successfully and smoothly passed through the tortuous vessel. We called this method the “lead anchor technique” (Figure 2). By obtaining superior cannulation catheter support, we were able to implant the LV lead at a low pacing threshold and without a phrenic nerve stimulation site (Figure 3). After CRT implantation, the pacing threshold was not increased, the QRS complex improved to 170 ms, and heart failure could be controlled.