NEW INFORMATION IN UNDERSTANDING HYPERTROPHIC CARDIOMYOPATHY

Hypertrophic cardiomyopathy (HCM) is a thickening of the heart wall (typically the left ventricle).  The cause of HCM is a genetic mutation of the cardiac sarcomere (cardiac muscle cell).  The condition is described as obstructive (70% of cases) and non-obstructive in nature.  The prevalence is 1 case in 500 – 1000 population and is the most common genetic disorder of the heart.  HCM is one of the many (and the most common) cardiac conditions that can lead to sudden cardiac arrest (SCA) in athletes.  Diagnosis of HCM in athletes is particularly challenging because athletes tend to have larger hearts and ultimately a thicker left ventricle wall because of their intense training and conditioning. 

SIGNS AND SYMPTOMS

The most common signs and symptoms for HCM include dysnea (difficulty breathing), angina, dizziness, palpitations, and syncope (fainting).  Unfortunately, many times the conditions is asymptomatic and sudden cardiac death could be the most dramatic and only symptom of HCM.  Sudden death from HCM typically occurs during or following strenuous exercise.

RISK FACTORS

First degree risk factors:

-          Family history of sudden cardiac death (<45 years old)

-          Recurrent syncope (fainting)

-          Left ventricle hypertrophy (LVH)

-          Abnormal blood pressure response during exercise

For more factors, click HERE (see page 4).

DIAGNOSIS AND TREATMENT

If you would like more specific information on the diagnosis and treatment guidelines for HCM, click HERE for the standards published in November 2011 by the American Heart Association (AHA) and the American College of Cardiology Foundation (ACCF).

CURRENT RESEARCH

The most recent information available on the topic of HCM has been provided by researchers at Stanford University.  Researchers are investigating the underlying causes of the genetic mutation of the cardiac sarcomere.  Results of this study showed that calcium dysregulation (calcium elevation) was likely to lead to HCM.  Restoration of calcium homeostasis (balance) prevented hypertrophy (enlargement of heart) and other physiological irregularities.  The authors are hopeful that these finding can lead to improved and novel treatments for the condition.  Current treatment includes adapting physical activities and in severe cases implantation of a pacemaker.  To read the press regarding the study’s publication and its potential implications, click HERE.

For other readings on HCM, check out these links:

Uptake of Cardiac Screening and Genetic Testing Among Hypertrophic and Dilated Cardiomyopathy Families

Progress With Genetic Cardiomyopathies

Athlete’s Heart of Hypertrophic Cardiomyopathy?

Exercise and Heart Disease:  From Athletes and Arrythmias to Hypertrophic Cardiomyopathy and Congenital Heart Disease

Submitted by Heather L. Clemons, MS, MBA, ATC