The most complete description of exercise testing in adults is by Nylander et al who paid particular attention to exercise capacity, symptoms and blood pressure response. They tested 76 adults ranging from 52 to 78 years of age; 77 percent had a history of chest pain, 74 percent had congestive…
James et al developed an exercise profile consisting of ST segment depression of 2 mm or more, a decreased systolic blood pressure response of two standard deviations below normal and a decreased total work capacity of two standard deviations below normal. Two or more of these responses occurred predominantly among…
Exercise Testing in Subjects with Aortic Stenosis Although studies have delineated possible mechanisms for effort syncope in aortic stenosis, a review of the literature (Thble 1) demonstrates rare complications from exercise testing when performed with appropriate caution and monitoring. Although used predominantly in pediatric cardiology to assess congenital aortic stenosis…
Four mechanisms leading to decreased cerebral perfusion and syncope—carotid hyperreactivity, left ventricular failure, arrhythmia, and left ventricular baroreceptor stimulation—were addressed by Richards et al. They studied four subjects with aortic stenosis (three with syncope, one with heart failure) using electrocardiographic and pressure monitoring of the pulmonary and brachial arteries. During…
Perhaps the most plausible explanation for syncope during exercise in patients with aortic stenosis is left ventricular stretch baroreceptor or mechano-receptor stimulation with concomitant arterial hypotension, reduced venous return, and bradycardia. Ross and colleagues demonstrated that elevation of left atrial and left ventricular pressures in dogs caused a decrease in…
In this patient, inadequate attention had been paid to warning signs. The initial heavy workload of the Bruce protocol (5 METs), infrequent blood pressure monitoring, continuation of the test despite a blunted blood pressure response, and physician inexperience may all have contributed to this catastrophe. Fortunately, the patient survived and…
Physical Examination Blood pressure was 150/90 mm Hg, regular pulse rate of 86, and respirations 16. He was a well developed, well nourished elderly white male. HEENT was normal, and the neck was supple without adenopathy Jugular venous pulse was non-distended with normal a and v waves. Carotids were slightly…