Serotonin is a chemical messenger that plays a crucial role in various bodily functions, including mood regulation, digestion, and sleep. However, research published in 2023 suggests that this chemical may also influence the mitral valve, a small but vital structure that performs a critical job during every heartbeat. The multicenter investigation, led by researchers at Columbia University’s Department of Surgery, in collaboration with the Pediatric Heart Valve Center at Children’s Hospital of Philadelphia (CHOP), the University of Pennsylvania, and the Valley Hospital Heart Institute, found evidence that reduced activity of the serotonin transporter may accelerate damaging changes in valves already affected by degenerative mitral regurgitation (DMR).

DMR is one of the most common forms of heart valve disease. As the valve tissue degenerates, the thin flaps that should meet neatly can thicken, stretch, or lose their normal shape. The valve can no longer seal completely, allowing blood to leak backward into the left atrium (regurgitation). This leak can raise pressure toward the lungs while reducing the amount of oxygen-rich blood that moves forward through the heart. Some people have no noticeable symptoms at first, but as the condition progresses, fatigue and shortness of breath can develop.

The heart must also work harder to maintain circulation. Over time, that added strain can permanently damage the heart and contribute to serious conditions such as atrial fibrillation and heart failure. Atrial fibrillation is an irregular heart rhythm, while heart failure means the heart cannot pump enough blood to meet the body’s needs. Medicines can ease symptoms and help manage complications, but they cannot reverse the underlying degeneration of the mitral valve.