Cardiology is a fellowship, not a residency. It is a subspecialty of internal medicine, which means you must first complete a three-year internal medicine residency before entering a separate three-year cardiology fellowship. The full training path from medical school graduation to practicing cardiologist takes a minimum of six years, and it can stretch to eight or nine if you pursue an additional subspecialty within cardiology.
Why the Distinction Matters
In medical training, a residency is the first stage of hands-on education after medical school. It covers a broad field like internal medicine, surgery, or pediatrics. A fellowship comes after residency and focuses on a narrower subspecialty within that field. Cardiology falls into the fellowship category because heart and vascular medicine is a subspecialty of internal medicine, not a standalone training track.
This means there is no such thing as a “cardiology residency” in the United States. A physician who wants to become a cardiologist applies to internal medicine residency programs first, trains as a general internist for three years, and then applies separately for a cardiology fellowship.
The Internal Medicine Residency: Years 1 Through 3
The foundation for cardiology is a three-year categorical internal medicine residency. During these years, trainees rotate through a wide range of medical subspecialties: pulmonology, gastroenterology, nephrology, infectious disease, and of course, cardiology. The goal is to build a broad base of knowledge in diagnosing and managing adult diseases before narrowing focus.
Residents who know early on that they want cardiology will typically seek out extra elective time on cardiology rotations, pursue research in heart-related topics, and build relationships with cardiologists who can write strong recommendation letters. The cardiology fellowship match is one of the most competitive in medicine, so planning usually begins well before the third year of residency.
The Cardiology Fellowship: Years 4 Through 6
The general cardiovascular disease fellowship is 36 months long. The American Board of Internal Medicine requires at least 24 of those months to be clinical, meaning fellows spend the majority of their time directly caring for patients with heart disease rather than doing research alone.
Training covers an extensive list of conditions: acute coronary syndromes, heart failure, arrhythmias, valve disease, cardiomyopathy, pulmonary hypertension, pericardial disease, peripheral vascular disease, and more. Fellows also learn to perform and interpret key procedures, including echocardiography, exercise stress testing, electrocardiography with ambulatory monitoring, right-heart catheterization, left-heart catheterization, and diagnostic coronary angiography.
At the end of fellowship, graduates are eligible to sit for the ABIM cardiovascular disease board exam. Passing this exam grants board certification in cardiology, and many physicians stop here to practice as general cardiologists.
Subspecialty Fellowships Beyond General Cardiology
Some cardiologists choose to train even further by completing an additional fellowship in a cardiology subspecialty. These programs typically add one to two more years of training on top of the general cardiology fellowship.
- Interventional cardiology: A 12-month fellowship focused on catheter-based procedures like stenting and balloon angioplasty. Fellows spend most of their week in the cardiac catheterization lab, with additional time in clinics for coronary artery disease and structural heart procedures like transcatheter aortic valve replacement.
- Clinical cardiac electrophysiology: Focuses on heart rhythm disorders. The combined cardiology and electrophysiology training must total at least four years, with the electrophysiology portion typically lasting one to two years. Some programs recommend a fifth total year of training to build competency in complex ablation procedures.
- Advanced heart failure and transplant cardiology: A one-year fellowship covering mechanical circulatory support devices, heart transplantation, and the management of patients with end-stage heart disease.
A physician who completes internal medicine residency, general cardiology fellowship, and then an interventional or electrophysiology fellowship will have spent seven to eight years in postgraduate training after medical school.
The Pediatric Cardiology Path
There is one important variation. Physicians who want to treat children with heart disease follow a different residency track. Instead of internal medicine, they complete a three-year pediatrics residency (or a combined internal medicine-pediatrics residency), then enter a three-year pediatric cardiology fellowship. The fellowship length is the same as adult cardiology, but the prerequisite residency and the clinical focus are different.
How the Application Process Works
Cardiology fellowships are filled through the National Resident Matching Program, the same matching system used for residency placement. The cardiovascular disease match falls under the Medicine and Pediatric Specialties Match, and it runs on its own calendar separate from the main residency match.
For a typical July start date, the match opens in late August of the prior year. Applicants submit their materials and interview through the fall. Ranking opens at the end of September, rank order lists are due in mid-November, and Match Day falls in early December. This means most applicants learn where they will train about seven months before their fellowship begins.
Pay During Training
Both residents and fellows are paid a stipend based on their postgraduate year level, commonly abbreviated as PGY. The pay increases modestly each year. As a reference point, at the University of Tennessee, a PGY-1 (first-year resident) earns roughly $62,400 per year, while a PGY-4 (which is the first year of cardiology fellowship for most trainees) earns about $69,500. By PGY-7, the stipend reaches approximately $77,800. These figures vary by institution and region, but the general pattern holds: fellowship pay is slightly higher than residency pay because it reflects additional years of training, not a jump to attending-level salary.
The financial leap comes after fellowship ends. Board-certified cardiologists in practice earn significantly more than trainees, though the years of relatively modest pay during six-plus years of postgraduate training are a real consideration for anyone weighing this career path.