18 year old white male presents to the ED after passing out during his last basketball game as a high school senior. Patient recalls that the event occurred shortly after a steal and a fast break down the court. He remembers that after scoring he began to feel light headed and weak. The next thing he remembers is waking up on the court surrounded by all of his teammates, and the team nurse. 911 was called and he was immediately brought to you. He claims to feel fine now and appears relaxed. His mother is crying and keeps saying “this can’t be happening again.”
What questions would you like to ask the patient and his family?
Pmhx: none, other then the occasional cold he reports being a healthy athletic kid
What is in your differential diagnosis at this time?
What is your next step to assess this patient?
What to do next? Imaging? Labs? Send home?
Now ready to send home?
2) Echo- used if still unsure of diagnosis, or if need to visualize the heart
Any thoughts now?
(is used to screen all athletes in Italy for HCM, not yet used as a screening tool in the US)
- Two-dimensional echocardiography is the usual method of diagnosis. Echocardiography can be used to confirm the size of the heart, the pattern of ventricular hypertrophy, the contractile function of the heart, and the severity of the outflow gradient. It has the advantages of high resolution and no known risk.
Echocardiography has been used extensively both as an aid to diagnosis and for research into the pathophysiology of hypertrophic cardiomyopathy (HOCM). It is characterized by an abnormal arrangement of the myocardial cells, which instead of lying in parallel rows, form whorl-like patterns. It most commonly affects the interventricular septum, but may also involve the entire myocardium or occur in isolated areas undetectable except by detailed histopathologic examination. As shown in the above echo, the interventricular septum is enlarged, thus creating an outflow tract obstruction.
This is a histological section of the conduction system in the septum which shows the aberrant myofibers
Disarray and disorganization of myocardial fibers, showing abnormal branching, overlapping and hypertrophy, with interstitial plexiform fibrosis