It's a holiday filled with hearts, so what better time to show this vital, fist-sized organ some extra love? "Heart disease remains the number one killer of Americans," said Dr. Ashish Sarraju, preventive cardiology at Cleveland Clinic. Dr. Sarraju says the U.S. had come a long way in lowering the number of deaths due to cardiovascular disease. But the latest data from the American Heart Association shows nearly 916,000 American died in 2023.