abnormal blood pressure response during exercise. History of
multiple sudden deaths in the family is an important risk factor.
- Ambulatory monitoringof all patients with a diagnosis of HCM is
mandatory and this should be for at least 48 hours.
- Exercise electrocardiographyis also mandatory. Patients with HCM
should undergo a metabolic exercise test with frequent blood
pressure monitoring (every minute during exercise and for 5
minutes during recovery). An abnormal BP response is an
important non-invasive marker of risk. The peak oxygen
consumption during the exercise also helps identify those with
significant limitation of exercise capacity.
- Non-sustained ventricular tachycardia (5 beats rate of 120
beats) especially if repetitive, is also associated with increased
risk of sudden death.
Additional investigations in patients with syncope
In these patients, additional investigations should be aimed at
determining the mechanism.
- Repetitive Holter recordings should be made.
- Tilt table test and if necessary.
- Electrophysiological study to exclude accessory pathway.
Other investigations that may be useful but not mandatory
This includes electrophysiological studies and rarely a thallium
scan for myocardial ischaemia. It is necessary to exclude significant
coronary artery disease with a coronary angiogram in patients
>40 years old, smokers or those with severe chest pain.
RReeaaddiinngg lliisstt
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