Brittany Stahl of Hillsborough, New Jersey, was dealing with plenty of stress when she felt tired and short of breath in 2019. “I thought it was probably bronchitis.” When breathing became so difficult that she struggled to do household chores or even lie flat, she sought urgent care for her presumed infection. But a chest X-ray and EKG (electrocardiogram) suggested a more concerning possibility: heart trouble. Read more.