Multicenter experiences with a single lead electrode for dual chamber XXXX systems.

@entity1 @entity1479 @entity162 @entity591 @entity956
Monitoring of atrial signals improves the accuracy in identifying supraventricular @entity591 to prevent inappropriate therapies in @entity1 with implantable ICDs. Since difficulties due to the additional atrial lead were found in dual chamber @entity1479 systems with two leads, the authors designed a single pass VDD lead for use with dual chamber ICDs. After a successful animal study, the prototype VDD lead (single coil defibrillation lead with two additional fractally coated rings for @entity162 sensing in the atrium) was temporarily used in 30 @entity1 during a German multicenter study. Atrial and ventricular signals were recorded during sinus rhythm (SR), @entity956 , AF, and VT or VF. The implantation of the lead was successful in 27 of 30 @entity1 . Mean atrial pacing threshold was 2.5 +/- 0.9 V/0.5 ms, mean atrial impedance was 213 +/- 31 ohms. Atrial amplitudes were greater during SR (2.7 +/- 1.6 mV) than during @entity956 (1.46 +/- 0.3 mV, P < 0.05) or AF (0.93 +/- 0.37 mV, P < 0.01). During VF atrial "sinus" signals had significantly (P < 0.01) lower amplitudes (1.4 +/- 0.52 mV) than during SR. The mean ventricular sensing was 13.3 +/- 7.9 mV and mean ventricular impedance was 577 +/- 64 ohms. Defibrillation was successful with a 20-J shock in all @entity1 . In addition, 99.6% of P waves could be detected in SR and 84.4% of flutter waves during @entity956 . During AF, 56.6% of atrial signals could be detected without modification of the signal amplifier. In conclusion, a new designed VDD dual chamber lead provides stable detection of atrial and ventricular signals during SR and @entity956 . Reliable detection of atrial signals is possible without modification of the @entity1479 amplifier.
