1.   An unnecessary defibrillator firing can itself trigger an erratic heartbeat that could potentially be life-threatening, cardiologists say.

2.   An unnecessary defibrillator firing can trigger an erratic heartbeat that could be life-threatening, cardiologists say.

3.   An unnecessary defibrillator firing can trigger an erratic heartbeat that could potentially be life-threatening, cardiologists say.

4.   And he has found himself searching for ways to prevent incidents of erratic heartbeat that have plagued him along the way.

5.   And by the end he was searching for new ways to prevent incidents of the erratic heartbeat that plagued him along the way.

6.   Cortisol, production of which Gold has found to be stepped up in depressed patients, can exacerbate arrhythmias, the erratic heartbeats that often precede sudden death.