From the Guidelines
HCM and HOCM are not exactly the same, though they are related conditions, with HCM being the broader term that refers to a genetic heart condition characterized by abnormal thickening of the heart muscle, and HOCM being a specific subtype of HCM where the thickened heart muscle causes an obstruction to blood flow from the left ventricle to the aorta.
Key Differences
- HCM is a genetic heart condition characterized by abnormal thickening of the heart muscle, particularly the left ventricle [ 1 ].
- HOCM is a specific subtype of HCM where the thickened heart muscle causes an obstruction to blood flow from the left ventricle to the aorta [ 1 ].
Clinical Implications
- The distinction between HCM and HOCM is important for treatment approaches, as HOCM may require specific interventions to address the obstruction, such as beta-blockers, calcium channel blockers, disopyramide, septal myectomy surgery, or alcohol septal ablation [ 1 ].
- Non-obstructive HCM may be managed differently, focusing on symptom control and prevention of complications like arrhythmias [ 1 ].
Diagnosis and Management
- The diagnosis of HCM and HOCM requires careful evaluation, including clinical markers and testing strategies to distinguish them from other cardiac conditions with left ventricular hypertrophy [ 1 ].
- Both conditions share the same genetic basis and carry risks of heart failure, arrhythmias, and sudden cardiac death, requiring careful monitoring and management [ 1 ].
From the Research
Definition and Classification
- Hypertrophic cardiomyopathy (HCM) is a primary disorder of the heart muscle characterized by muscular hypertrophy without a recognized cause, which encroaches on the ventricular chamber, reducing chamber area and volume 2.
- HCM can be classified into two types: obstructive (HOCM) and non-obstructive (HNCM), depending on the presence of left ventricular outflow tract (LVOT) obstruction at rest or during provocation 3, 4.
HCM and HOCM
- HOCM is a subtype of HCM, characterized by the presence of a LVOT gradient at rest or during provocation, such as with Valsalva maneuver or exercise 3.
- Not all patients with HCM have HOCM, as some may have non-obstructive HCM (HNCM) 4.
- The symptoms and treatment of HCM and HOCM may differ, with HOCM requiring specific therapies to reduce dynamic obstruction 3, 4, 5.
Key Differences
- The main difference between HCM and HOCM is the presence of LVOT obstruction, which is a key feature of HOCM 3, 4.
- HOCM is characterized by a higher risk of sudden cardiac death and requires specific therapies to reduce dynamic obstruction 3, 4, 5.
- The treatment of HCM and HOCM may involve different approaches, including pharmacologic therapy, septal reduction therapy, and surgical interventions 3, 4, 6, 5, 2.