Lab Studies:
Genetic Testing – pathologic variant in MYBPCS c.1224-52 G>A
Other Studies:
EKG – new T wave inversions at V3-6. Case Photo #1
Ambulatory cardiac monitor, Zio patch – worn for two weeks with no arrhythmias noted
Trans-thoracic echocardiogram – mild concentric left-ventricular hypertrophy with maximal
septal wall thickness measuring 14mm in the basal septum, corresponding to an adolescent Z
score of 1.5. Mild systolic anterior motion but no significant left ventricular outflow obstruction.
Cardiac MRI Case Photo #2 Case Photo #3 – Showed asymmetric hypertrophy of the septum and anterior wall of the left
ventricle diagnostic of hypertrophic cardiomyopathy. Basal septum measured 22mm and
maximal anterior wall thickness of 27mm in a focal area of the anterior free wall. There was
systolic anterior wall motion with flow acceleration through the left-ventricular outflow tract,
Ejection fraction noted to be 67% with no late gadolinium enhancement (LGE), and normal
coronary arteries.
Over-read of TTE after CMR findings – poor technique and incorrect septal wall measurements.
Cardiopulmonary Exercise Test (CPET) – no ventricular arrhythmias noted, normal cardiovascular response to exercise, with an overall impression of reduced exercise endurance for age with VO2 max 25.6/kg/min representing 20-30% of predicted VO2 max for age and body
habitus (35.3mL/kg/min).
Consultations:
Pediatric Cardiologist – performed TTE. Even though initial echocardiogram revealed an
adolescent Z score of 1.5, a cardiac MRI was recommended given the patient’s history of
Kawasaki’s disease.
Click here to continue. Challenge yourself by writing down a revised, working diagnosis before moving to the next slide.