A new pacemaker for monitoring asystole and prevention of Adams-Stokes syndrome and sudden cardiac death.

Patients with suspected Adams-Stokes syndrome are examined by Holter monitoring. During the monitoring, there is the danger of syncopes occurring and there are even reports of sudden cardiac death. We therefore developed a pacemaker for cardiac arrest monitoring and the prevention of Adams-Stokes syndrome and sudden cardiac death, which has the following functions: (1) the longest escape interval of the pacemaker not exceeding the value at which syncope is induced is determined by the decline of the mean heart rate including the asystole to a certain threshold rate; (2) once the pacemaker escapes from the interval it continues pacing for a while at a physiological rate to allow recover from ischemias in organs or tissues; and (3) to prevent overdrive suppression to the heart, the pacing rate gradually declines and stops pacing until the next asystole. This pacemaker is useful not only in the diagnosis of Adams-Stokes syndrome but also in pharmacological and pathophysiological studies and in determining when pacing should cease.