A method and apparatus for reducing the incidence of atrial arrhythmias by using an overdrive algorithm to determine the application of overdrive stimulation pulses to a patient’s heart, e. The method includes first, second, and third cut-off steps that leave a part having a length capable of preventing cracking of a remaining resistance film. In the method, the head system is advanced in the first direction over the substrate while dispensing drop sets for each array from dispenser sets so as to form the arrays.