When patients present with shortness of breath, physicians often face a quandary: Is it the heart or is it the lungs? What is the relationship between chronic obstructive pulmonary disease, or COPD, and cardiac function? Are patients with even subclinical emphysema at risk for showing reductions in cardiac output and left ventricular volume? Dr. Karol Watson, director of the Women's Cardiovascular Center, co-director of the program in preventative cardiology, and director for the Center for Cholesterol and Hypertension Management at the University of California Los Angeles, discusses recent findings about mild- to moderate-COPD and cardiac function, and how this new evidence should impact the way physicians diagnose and manage patients with shortness of breath. Dr. Janet Wright hosts.