John Tretter is a Cardiologist in Casa Grande, Arizona. Dr. Tretter is highly rated in 2 conditions, according to our data. His top areas of expertise are Cardiomyopathy, Dilated Cardiomyopathy (DCM), Atrial Fibrillation, and Arrhythmogenic Right Ventricular Cardiomyopathy. Dr. Tretter is currently accepting new patients.