Preliminary experience with the helifix electrode for transvenous atrial implantation.

A Helifix electrode was inserted transvenously in the right atrial appendage for temporary atrial stimulation in three patients. The low stimulation threshold as well as the excellent stability of the electrode encouraged us to proceed to permanent implantation of this lead in thirteen patients. The lead was introduced through the saphenous vein in twelve patients and through the cephalic vein in one patient. Five patients had sinoatrial dysfunction and five had bradycardia-tachycardia syndrome; they received atrial demand pacemakers. Two patients had atrioventricular block and received atrial synchronous ventricular pacemarkers. Our last patient had restrictive cardiomyopathy, heart failure and a drug-refractory atrial arrhythmia. She received a dual-chamber sequential pacing device. Atrial electrode displacement occurred in one patient soon after implantation. The lead was promptly repositioned without difficulty. Partial sensing of spontaneous P waves was observed in two patients. One recovered spontaneously, the second after substituting a pulse generator with a higher input sensitivity. Our clinical experience during the period from November 1977 to January 1979 has shown that the Helifix electrode is suitable for transvenous atrial implantation.