Dr. Lloyd Marks is a Board certified Pediatric Cardiologist in Northern New Jersey, serving Union County, Middlesex County, Essex County and Hudson County. His practice is restricted to pediatric cardiology, fetal cardiology, and adult congenital cardiology; Dr. Marks performs all tests personally including echocardiograms and cardiac catheterizations. He feels that his job is not complete unless you have an complete understanding of your (your child's) problem.