Print Departments and specialties Mayo Clinic has one of the largest and most experienced practices in the United States, with campuses in Arizona, Florida and Minnesota. Staff skilled in dozens of specialties work together to ensure quality care and successful recovery. Departments that treat this condition Cardiovascular Medicine Cardiovascular Surgery Pediatric Cardiac Surgery Doctors who treat this condition Edit search filters close Narrow your search By location Phoenix/Scottsdale, AZ Rochester, MN By last name Find a doctor whose last name begins with the letter A A Find a doctor whose last name begins with the letter B B Find a doctor whose last name begins with the letter C C There are no doctors whose last name begins with the letter D D There are no doctors whose last name begins with the letter E E There are no doctors whose last name begins with the letter F F Find a doctor whose last name begins with the letter G G active Find a doctor whose last name begins with the letter H H There are no doctors whose last name begins with the letter I I There are no doctors whose last name begins with the letter J J There are no doctors whose last name begins with the letter K K There are no doctors whose last name begins with the letter L L Find a doctor whose last name begins with the letter M M There are no doctors whose last name begins with the letter N N There are no doctors whose last name begins with the letter O O Find a doctor whose last name begins with the letter P P Find a doctor whose last name begins with the letter Q Q There are no doctors whose last name begins with the letter R R There are no doctors whose last name begins with the letter S S There are no doctors whose last name begins with the letter T T There are no doctors whose last name begins with the letter U U There are no doctors whose last name begins with the letter V V There are no doctors whose last name begins with the letter W W There are no doctors whose last name begins with the letter X X There are no doctors whose last name begins with the letter Y Y There are no doctors whose last name begins with the letter Z Z Reset all filters Search Tips Use quotes for phrases. Even if there are no auto-suggestions within the search field, hit "Search" anyway, as you may still get results. Displaying 1-1 out of 1 doctors available Last Name Initial: H Donald J. Hagler, Sr., M.D. Pediatric Cardiologist Rochester, MN Phoenix, AZ Areas of focus: Cardiac catheterization, Fetal echocardiogram, Transesophageal echocardiogram, Echocardiogram, Percutaneous valve proce...dure, Heart disease, Atrial septal defect, Congenital heart disease, Patent foramen ovale, Ventricular septal defect, Patent ductus arteriosus Show more areas of focus for Donald J. Hagler, Sr., M.D. By Mayo Clinic Staff Request an appointment Diagnosis & treatment Oct. 23, 2024 Print Living with ventricular septal defect (VSD)? Connect with others like you for support and answers to your questions in the Heart & Blood Health support group on Mayo Clinic Connect, a patient community. Heart & Blood Health Discussions Statin discontinued due to neuropathy. What are some alternatives? 437 Replies Tue, Jul 14, 2026 chevron-right Fibromuscular dysplasia (FMD): Want to connect 128 Replies Tue, Jul 14, 2026 chevron-right High Ferritin Levels: How can I lower my levels? 40 Replies Thu, Jul 09, 2026 chevron-right See more discussions Related Ventricular septal defect Associated Procedures Cardiac catheterization Chest X-rays Echocardiogram Electrocardiogram (ECG or EKG) Show more associated procedures Products & Services A Book: Mayo Clinic Family Health Book Newsletter: Mayo Clinic Health Letter — Digital Edition Show more products and services from Mayo Clinic Ventricular septal defect (VSD)Symptoms&causesDiagnosis&treatmentDoctors&departments Research: It's all about patients Show transcript for video Research: It's all about patients [MUSIC PLAYING] Joseph Sirven, M.D., Professor of Neurology, Mayo Clinic: Mayo's mission is about the patient. The patient comes first. So the mission and research here is to advance how we can best help the patient, how to make sure the patient comes first in care. So in many ways, it's a cycle. It can start with as simple as an idea worked on in a laboratory, brought to the patient bedside, and if everything goes right — and let's say it's helpful or beneficial — then brought on as a standard approach. And I think that is one of the unique characteristics of Mayo's approach to research — that patient-centeredness — that really helps to put it in its own spotlight. CON-20316971 Diseases & Conditions Ventricular septal defect (VSD)