The most common heart valve problem is aortic valve stenosis—when calcium gradually builds up on the aortic valve, causing it to stiffen and narrow over time. In this Doctor’s Note, Loyola Medicine cardiologist Clifford Kavinsky, MD, explains how the heart’s four valves keep blood flowing in the right direction—and what happens when one stops working properly. He also highlights how TAVR (Transcatheter Aortic Valve Replacement) offers a minimally invasive alternative to open‑heart surgery, givin