Cameron Health, a San Clemente, Calif., medical-device maker, has raised $14.1 million of a planned $50 million fifth funding round, I’ve learned. The company is working on a new type of implantable defibrillator that’s designed to be easier to implant and program than existing models.

Implantable defibrillators administer shocks to the hearts of people who are at risk of cardiac arrest — a critical condition in which the heart simply stops beating. When the device senses a heart-rhythm disturbance, it shocks the heart back into action. A cardiologist at the University of Iowa Hospitals and Clinics describes the device in more detail.

Existing defibrillators must be implanted in an invasive procedure that requires a specialist — often an electrophysiologist — to guide lead wires into the heart through the veins. In addition to being challenging to insert, those leads can sometimes break, in rare occasions delivering fatal shocks to the heart.

Cameron’s simpler defibrillator apparently doesn’t require such leads, making it easier to implant — although exactly how it accomplishes that trick isn’t immediately clear. The trade publication In Vivo took a closer look at Cameron back in 2003, although the portion of its article available on the Web doesn’t explain how the Cameron device functions without leads.

Investors in the round so far include Three Arch Capital, Versant Ventures, Sorrento Ventures and Delphi Ventures. Cameron CEO Jay Warren didn’t return multiple phone calls and emails requesting comment; neither did VC investors at Three Arch and Versant.