A New Atrial Lead with Improved Stability and P‐Wave Detection

A new segmented polyether polyurethane atrial pacemaker lead has been developed and tested acutely and chronically in dogs. This lead was constructed so that its tip could q uick-ly and accurately be positioned in close proximity to the S-A node and provide long-term stability without the use of active fixation devices such as tines or screws. The acute intrinsic P-wave potentials seen at the S-A node area (9.7 ± 4.7 mV) were superior to those defected in the appendage (4.7 ± 2.8 mV) and coronary sinus (6.8 ± 4.1 mV). There were no significant differences in pacing thresholds between sites. In long-term studies, transvenous (juguiar) leads maintained their position for over three months without dislodgment in active unrestrained dogs with only a 25% decrease in intrinsic P-wave potentials. The chronic pacing thresholds for this lead were similar, or superior, to those reported for other pacemaker lead placement sites. The polyurethane coating material produces no adverse tissue reaction or thrombosis.