Heart disease and lung disease go together so often that the finding of one should prompt a search for the other. In patients with COPD the diagnosis of heart disease can be difficult because many of the symptoms (shortness of breath with activity, chest tightness, etc) occur with both diseases. What this means is that physicians need to have what is called a “high index of suspicion” that heart disease may be present in their COPD patients, and could be the cause of the patient’s symptoms, particularly if their symptoms are out of proportion to the degree of lung disease found.
To put some numbers to the facts, 20% of COPD patients will have some type of cardiovascular disease diagnosed. When it comes to hospitalized patients, 55% of patients admitted with a COPD exacerbation are found to have some type of cardiovascular disease (but only if someone looks for it). 20% of COPD exacerbations are due to decompensated heart failure or irregular heart beatings. Patients admitted to the hospital for a COPD exacerbation are often found to have biochemical evidence of heart damage or strain associated with the event. The cause for these findings can be several fold. COPD patients often experience low oxygen levels during exacerbations and this can be detrimental to the heart in several ways. The heart has a high oxygen requirement to function properly and low oxygen levels increase pressure in the blood vessels of the lungs making the heart work harder to pump blood.