The HCM medical abbreviation stands for hypertrophic cardiomyopathy, a condition in which the muscle wall of the heart, most often the left ventricle, becomes abnormally thick. Hypertrophic means grown larger, cardio means heart, and myopathy means a disease of muscle, so the name describes the problem fairly literally.
You may find HCM in a cardiology letter, an echocardiogram report, a sports physical, or the past medical history line of a hospital note. It is often inherited, so it can also show up in family history sections when a parent, sibling or child has been diagnosed. This guide covers what the letters mean in a chart, how HCM differs from look alike terms such as HOCM and LVH, and which tests and treatments tend to appear next to it.
At a glance
Stands for
Hypertrophic cardiomyopathyWord roots
Hyper (over) + trophic (growth); cardio (heart) + myo (muscle) + pathy (disease)Specialty
Cardiology, especially heart muscle and inherited heart disease clinicsWritten as
HCM; HOCM when the outflow of blood is blockedDo not confuse with
HCC (a liver cancer) and plain LVH from high blood pressureWhere you see it
Echo reports, cardiac MRI reports, problem lists, family history
What the HCM medical abbreviation describes
In hypertrophic cardiomyopathy the heart muscle thickens without an obvious outside cause such as long standing high blood pressure or a narrowed aortic valve. The thickening is often uneven. It frequently affects the septum, the wall that divides the left and right sides of the heart. A thick, stiff wall can make it harder for the heart to relax and fill between beats.
Many cases are linked to changes in genes that build the tiny contracting units inside heart muscle cells. Because of that, a diagnosis in one person often leads doctors to suggest screening for close relatives. Some people with HCM have no symptoms at all and learn about it from a routine test. Others notice shortness of breath with effort, chest discomfort, a racing or skipping heartbeat, lightheadedness, or fainting.
HCM versus HOCM and other look alike shorthand
Cardiology notes use several close cousins of this abbreviation. The main split is whether the thick wall gets in the way of blood leaving the heart.
| Shorthand | Meaning | How it differs |
|---|---|---|
| HCM | Hypertrophic cardiomyopathy | The umbrella term, with or without blockage |
| HOCM | Hypertrophic obstructive cardiomyopathy | The thick septum narrows the outflow path of the left ventricle |
| LVOT | Left ventricular outflow tract | The channel blood uses to exit; a gradient here signals obstruction |
| LVH | Left ventricular hypertrophy | A finding of a thick wall from any cause, often blood pressure |
| DCM | Dilated cardiomyopathy | The opposite shape: an enlarged chamber with a thin, weak wall |
So LVH is a description of what the heart looks like, while HCM is a specific diagnosis. A note that says LVH alone does not mean the person has HCM.
Reading HCM in a real chart line
From an echo report: "Asymmetric septal hypertrophy, septum 19 mm. Resting LVOT gradient 45 mmHg. Findings consistent with HCM, obstructive physiology." In plain words, the dividing wall is thicker than usual, blood speeds up as it squeezes past it, and the reader thinks this is the obstructive form often written HOCM.
Tests that confirm or follow the condition
The most common test is an ultrasound of the heart, often written TTE for transthoracic echocardiogram. It measures how thick the walls are and whether blood flow is blocked, sometimes while the person strains or exercises to unmask a hidden gradient. Cardiac MRI gives a sharper view of wall thickness and can show scarring inside the muscle. An EKG often looks abnormal, and longer heart rhythm monitoring looks for irregular beats.
Genetic testing is offered in many clinics. A positive result can guide which relatives need regular checks. Specialists use set cutoffs for wall thickness, and these differ when there is a known family history, so the exact numbers in a report are best read with the cardiologist.
Treatments you may see listed beside HCM
Medication lists often include a beta blocker such as metoprolol or a calcium channel blocker such as verapamil, which slow the heart and give it more time to fill. A newer class called cardiac myosin inhibitors, for example mavacamten, eases the overly strong squeeze that drives obstruction. Some people need a procedure to thin the septum, either surgical septal myectomy or alcohol septal ablation, both of which are named in operative notes.
Because HCM can raise the risk of dangerous heart rhythms, some patients receive an implanted defibrillator. Atrial fibrillation is also more common in this group, so a blood thinner may appear on the list. Activity guidance has changed over time and is now set person by person.
For students charting HCM
On a problem list, write the full diagnosis the first time if your facility asks for it, then the shorthand. Note whether the form is obstructive, the latest gradient, any device, and the screening plan for relatives. HCM sits among the heart conditions on the diagnosis abbreviations hub, next to CHF for heart failure and SCD, which in cardiology can stand for sudden cardiac death.
Everything above is broad background on a heart muscle condition. If HCM appears in your records or a relative's, a cardiologist who knows the details can walk you and your relatives through what it means.
Frequently asked questions
What does HCM stand for in cardiology?
HCM stands for hypertrophic cardiomyopathy. It means the heart muscle, usually of the left ventricle, is thicker than it should be without a clear outside cause.
Is HCM the same as HOCM?
Not exactly. HCM is the overall diagnosis. HOCM is the obstructive type, where the thick wall partly blocks blood leaving the heart, and many people with HCM have this form at rest or with effort.
Is hypertrophic cardiomyopathy inherited?
It often is. Many cases trace to a change in one of the genes that build heart muscle, and a parent with it has about a one in two chance of passing it to each child. That is why relatives are commonly offered an echo, an EKG or genetic testing.
Does LVH on my report mean I have HCM?
No. LVH simply describes a thick left ventricle, and the most common reason is long term high blood pressure. HCM is one possible cause among several, and only your clinician can sort out which applies.
Can someone with HCM have no symptoms?
Yes. Many people feel well and learn of it from a murmur, an abnormal EKG or a family screening test. Regular follow up still matters because the condition can change over time.