Leaking mitral valve lets blood move backward within heart

Ask Dr. Keith Roach M.D

DEAR DR. ROACH: I’m 87 and have survived melanoma, which is now under control. I garden, grow flowers and landscape daily. I keep busy two to three hours a day outside. But last week I was winded from a 12-step steep staircase. I was amazed. My doctor noted that I have “nonrheumatic mitral valve insufficiency.” Does this explain my shortness of breath? I’ve done the treadmill test twice over the past five years with good results. Is it just a reminder that I am 87? — R.K. ANSWER: The mitral valve connects the left atrium with the left ventricle, and it prevents the powerful contraction of the left ventricle from pushing blood backward into the left atrium and even into the lungs. “Insufficiency” of the valve, also called mitral regurgitation, means that the valve leaks, and some blood is flowing backward. In North America, rheumatic fever was a major cause of damage to the mitral heart valve prior to antibiotics, and it still is in undeveloped parts of the world. “Nonrheumatic” means that the damage to your mitral valve was not from rheumatic heart disease. Although many people have very small amounts of mitral valve insufficiency, developing symptoms is uncommon. The more the valve leaks, the more likely symptoms are to develop. The backward flow of blood means the heart has to work harder, since it has to repump all the blood forward again. Too many years of this leads to heart failure. In addition, the blood vessels of the lungs can be damaged by the constant backward flow in severe mitral insufficiency, leading to pulmonary hypertension. Further, the left atrium can enlarge if it’s constantly being overfilled by the left ventricle pushing blood under high pressure the wrong way. An enlarged left atrium is a risk for atrial fibrillation. Atrial fibrillation is a problem, especially in people who already have heart failure. Even though mitral valve insufficiency is usually pretty benign, when things go wrong, they can go wrong in a hurry. Your doctor should certainly do a physical exam, and if you have any change in a heart murmur, you may need an echocardiogram. Your cancer treatment may have a role, and there are many other possibilities for shortness of breath. These need to be evaluated before blaming your shortness of breath on your age. That’s a good rule of thumb for any new symptom. * * * DR. ROACH WRITES: I am often asked about screening tests for pancreatic cancer. Despite the promise of new tests, the U.S. Preventive Services Task Force just re-reviewed the available evidence and continues to recommend against screening in the general population. However, it’s important to recognize that these recommendations do not apply to people at increased risk for pancreatic cancer, such as those with familial pancreatic cancer or with some genetic syndromes, such as Peutz-Jeghers syndrome. However, it does apply to people with other risk factors for pancreatic cancer, including smokers and those with new-onset diabetes or chronic pancreatitis. With better screening tests, or with improved treatments for pancreatic cancer, the balance of benefits (it’s currently unlikely to find early pancreatic cancer when it can be treated) to harms (false positive results can lead to unnecessary surgery) may shift, but for now the recommendation is clear and strong that screening for pancreatic cancer is not recommended.