Patient case (clinical description): A 23-year-old man comes to the emergency department following an episode of syncope.  He was working out when he felt dizzy and passed out without head injury.  He has had 3 other episodes of light-headedness over the last year, all happening during physical activity. He never had this experience while resting. He has no other medical conditions.  The patient does not use tobacco, alcohol, or illicit drugs.  His father died suddenly at age 35.  Vital signs are within normal limits.  On physical examination, the patient has a harsh systolic murmur.  The lungs are clear with no peripheral edema. Echocardiography shows asymmetric interventricular septal hypertrophy.

Patient's own account: I'm 23, and I got admitted to the ER because I fainted all of a sudden. I was in the gym, working out, when all of a sudden, I just got dizzy and passed out. Hopefully, I didn't hit my head. It's not my first time having that kind of dizziness at the gym, never when I'm chilling at home tho. I don't have any special medical conditions and I'm not even smoking, drinking or doing drugs! My dad died suddenly when he was 35, so I'm kind of scared. My vitals were normal while at the ER and they did a physical exam and they told me my heart sounds abnormal. My lungs are ok, but I had to do an echography of my heart, and they told me it is bigger than average.

Clinical trial: Study of Exercise Training in Hypertrophic Cardiomyopathy

Eligibility criteria:
Inclusion Criteria:

          -  Age ≥ 18 years and ≤ 80.

          -  Diagnosis of HCM, defined by the presence of unexplained left-ventricular hypertrophy
             > 13 mm in any wall segment.

          -  Agreement to be a participant in the study protocol and willing/able to return for
             follow-up.

        Exclusion Criteria:

          -  History of exercise-induced syncope or arrhythmias (ventricular tachycardia or
             non-sustained ventricular tachycardia).

          -  Medically refractory left ventricular outflow tract obstruction being evaluated for
             septal reduction therapy.

          -  Less than 3 months post septal reduction therapy (surgery or catheter based
             intervention).

          -  Hypotensive response to exercise (> 20 mm Hg drop in systolic blood pressure from peak
             blood pressure to post exercise blood pressure).

          -  Pregnancy.

          -  Implantable Cardioverter-Defibrillator (ICD) placement in last 3 months or scheduled.

          -  Left ventricular systolic dysfunction (left ventricular ejection fraction < 55% by
             echocardiography).

          -  Worsening clinical status in the last 3 months, advanced heart failure (New York Heart
             Association class IV symptoms) or angina (Canadian Cardiovascular Society class IV
             symptoms).

          -  Life expectancy less than 12 months.

          -  Inability to exercise due to orthopedic or other non-cardiovascular limitations.

          -  Unwillingness to refrain from competitive sports, burst activity, or heavy isometric
             exercise for the duration of the study.
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Years old.
Subject must be at most 80 Years

Eligibility (NLI label): Contradiction