Emily Kalinowski was 16 years old when she was diagnosed with atrial fibrillation (AF or AFib), a condition most commonly diagnosed in patients age 70 or older.
Doctors managed her AFib, a condition characterized by irregular heart rhythm and fatigue, with medications for 15 years. But then she began having episodes where she felt like she was going to pass out, something that couldn’t be explained by AFib.
Kalinowski said she had seen multiple cardiologists in the Chicago area, where she is from, but her condition was still a bit of a mystery until she moved just south of Jackson, Tennessee, and went to the Atrial Fibrillation Precision Research Program clinic at VUMC.
The clinic arranges genetic testing for patients with AFib who may be at risk for inherited cardiomyopathy or arrhythmia syndromes. It’s an innovative approach driven by Vanderbilt research that shows AFib in younger patients can be the first sign of a genetic heart disease, said clinic founder Ben Shoemaker, MD, associate professor of Medicine. Without treatment, younger patients may develop other serious cardiac disorders such as heart failure or life-threatening ventricular arrhythmias.
Kalinowski’s genetic testing revealed she had a pathogenic mutation in the gene desmoplakin, and prior studies showed a mutation like hers carries a 50% risk of death or fatal arrhythmia by age 40, Shoemaker said. She was 31 at the time.
Based on her positive genetic test, VUMC specialists implanted a defibrillator and started her on medications that suppressed her ventricular arrhythmias and reduced progression of her cardiomyopathy, Shoemaker said. As a result, she is doing much better.
Kalinowski said she has been impressed with her care team at Vanderbilt.
“They’ve just really gone above and beyond,” she said. “They’re always just so quick to help and support and answer any questions, so I’m very thankful that I’ve been able to be a part of the program.”
Vanderbilt research, along with international collaborators, has shown that patients with atrial fibrillation who had positive genetic testing had a higher risk of mortality, specifically from heart failure and sudden death, and could benefit from closer surveillance and personalized care strategies.
This research, supported by the international cardiology community, has led to a change in practice guidelines. Genetic evaluations are now recommended for younger patients diagnosed with atrial fibrillation, especially if there are signs of other cardiac abnormalities or a family history of atrial fibrillation.
Vanderbilt researchers recently presented at the Heart Rhythm Society’s Scientific Sessions that more than 20% of patients referred to the Atrial Fibrillation Precision Research Program clinic for genetic testing since its establishment in April 2023 tested positive for genetic variants that increase risk for inherited cardiomyopathy or arrhythmia syndromes.
In other words, the clinic identified syndromes by genetic testing that may have been more difficult or lengthy to identify by other means, allowing physicians to deploy interventions to improve the quality of life and outlook for those patients.
The clinic, held every Thursday, includes Shoemaker, Zach Yoneda, MD, assistant professor of Medicine; Hollie Williams, APRN; Wendy Kilbourne, RN; and Cassady Pelphrey, MSc, CGC. They see between 10 and 20 patients weekly from several states, many of whom are young and don’t understand why they have AFib. “They’re hungry for someone who wants to explain why this is, why they have this heart problem, and most of them are overtly very healthy,” Shoemaker said.
The average AFib onset for patients seen in the clinic is mid-30s, Shoemaker said. About 10% of patients are endurance athletes, who carry special considerations for certain genetic heart conditions. A diagnosis “can be very helpful to them to inform their risk and develop strategies to safely continue exercise participation,” he said.
The positive genetic diagnoses can also be helpful to share with family members, many of whom also come in for testing and are found to carry the familial variant.
Shoemaker said the most common genetic mutation found is in the gene titin (TTN), which accounts for about one-third of the genetic diagnoses in their clinic. It is associated with dilated cardiomyopathy, a disease of the heart muscle that makes it more difficult to pump blood.
The good news is that patients diagnosed with the TTN mutation early in the course of their disease respond well to current medical therapies and AF ablation.
“By making an early diagnosis, we have the ability to reduce the risk of congestive heart failure and life-threatening arrhythmias, which can lead to the need for heart transplant or sudden death,” he said. “Our genetic diagnosis allows us to personalize the treatment for our patients.”
