Question

During a high school pre-sports participation event, you examine a generally healthy 16-year-old male. Vitals are all within normal limits. The boy is normally developed and well nourished. He is alert x 3. Neck inspection and palpation negative for masses or tracheal deviations. Cardiovascular exam reveals carotid pulse amplitude 2/3 B/L, normal contour, no thrills. Carotid auscultation negative for bruits. There is no neck vein distention. The apical impulse is sustained. Heart auscultation is positive for S4 and a systolic murmur grade 4/6 along the Llower stemal border and the apex. The murmur almost disappears (grade 2/6) with leg lifting and while the patient squats. What is the best assessment of the patient's status? Answers A-D А Risk for congenital aortic stenosis and sudden cardiac arrest during exercise o B Risk for exercise-induced asthma and sudden cardiac arrest during exercise o с Innocent heart murmur without risk for sudden cardiac arrest during exercise D Risk for hypertrophic cardiomyopathy and sudden cardiac arrest during exercise

Answer 1

Answer is option A

Risk for congenital aortic stenosis and sudden cardiac arrest during exercise

The murmur for aortic stenosis would be low to medium pitch. It has typical crescendo-decrescendo configuration. The intensity of murmur could be grade 2, 3 or 4. It increases with passive leg raising. The murmur fades during phase 2 of the Valsalva maneuver. This murmur may peak in either mid or late systole. There is tendency for the murmur to peak progressively later in systole as stenosis become more severe. Severity of valvular aortic stenosis includes a delayed carotid upstroke.

Some Basic Concepts

A murmur is a series of vibrations of variable duration, audible with a stethoscope at the chest wall, that originates from the heart.

A grade 1 murmur is so faint that it can be heard only with special effort. A grade 2 murmur is faint, but is immediately audible. Grade 3 refers is moderately loud, and grade 4 to a murmur that is very loud. A grade 5 murmur is extremely loud and is audible with one edge of the stethoscope touching the chest wall. A grade 6 murmur is so loud that it is audible with the stethoscope just removed from contact with the chest wall.

Different physiologic maneuvers and pharmacologic interventions that alter cardiovascular hemodynamics can be used to aid in the characterization and differentiation of cardiac murmurs.

Passive leg raising increases venous return. This venous return is first to the right and then to the left side of the heart. The pause after an extra systole increases ventricular filling. This enhances myocardial contractility.

Squatting produces an increase in venous return first to the right and then to the left side of the heart, and an increase in peripheral vascular resistance. This results in an increase in systemic blood pressure and in stroke volume.