ECG Quiz: A Heart Murmur and Dyspnea in a 65-Year-Old Runner
John D. Cantwell, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 5 - MAY 97
A baseline systolic heart murmur can intensify slightly with exercise, perhaps because of turbulent flow and the increased cardiac output. This patient's murmur, however, increased 2 grades—more than expected—and changed in character, becoming more musical and of higher pitch. Mitral valve prolapse, developing since his echocardiogram 4 years earlier, was a consideration but was excluded on a repeat echocardiogram. His resting ECG showed nonspecific T-wave inversion in the inferior and anterolateral leads (figure 2), a variation that dated back at least 14 years without significant changes and might have been related to his hypertension.
In view of the patient's coronary risk factors, we chose to do a thallium stress scan. The scan revealed a striking decrease in perfusion in the septum, apex, and a portion of the anterior wall, with good redistribution.
Cardiac catheterization revealed a 90% lesion of the proximal left anterior descending (LAD) coronary artery, a 70% occlusion of the distal LAD, a 70% narrowing of the first obtuse marginal branch of the circumflex artery, and a 90% lesion of an intermediate ramus branch. His left ventricular function was normal.
Painless ischemia of the myocardium and papillary muscles, with resultant papillary muscle dysfunction, might have been the cause of both his systolic murmur (which sounded like mitral regurgitation) and his effort-related dyspnea.
The patient underwent four aortocoronary bypass grafts. The postoperative course was complicated by bleeding (necessitating a return to the surgical suite) and a pulmonary embolus. On a follow-up visit 5 months later, he was doing well, walking 15 miles per week. He experienced only a little dyspnea when walking rapidly uphill. He exercised for 11 minutes on the Bruce treadmill protocol, stopping because of mild leg fatigue. No heart murmur was noted postexercise.
Ischemic heart disease can occasionally manifest itself in unusual ways. Sometimes patients will even present at a dentist's office, because of aching in their teeth and jaw with certain activities. In this case, effort-induced dyspnea and a change in the intensity and characteristics of the heart murmur were likely due to underlying coronary insufficiency. Shortness of breath can be an early indicator of coronary disease, even in the absence of chest pain. Cook and Shaper (1) studied the relationship of breathlessness to angina pectoris in 7,735 middle-aged men. In a 5-year follow-up, 25% of the men who had complained of dyspnea with activity developed angina, and 5% had heart attacks. Hagman and Wilhelmsen likewise found in their study (2) of 5,287 Swedish men that dyspnea may precede angina as an indicator of coronary heart disease. A recent report (3) mentions a postexercise ventricular gallop sound as another possible indication of underlying myocardial dysfunction or ischemia.
In addition to asking patients about effort-related chest pain or discomfort, one should inquire about increasing dyspnea on exertion. It is also appropriate to listen to the heart after exercise testing for exercise-induced gallops or significantly augmented or altered heart murmurs. Having a patient run in place is one way to evaluate the change, if any, in a murmur. Sometimes a murmur, such as a mitral stenosis, will appear de novo following exercise.
Dr Cantwell is director of preventive cardiology and cardiac rehabilitation at Georgia Baptist Medical Center and clinical professor of medicine at Morehouse School of Medicine in Atlanta. He is a member of the editorial board of The Physician and Sportsmedicine. Address correspondence to John D. Cantwell, MD, 755 Mt Vernon Hwy, Suite 530, Atlanta, GA 30328.
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