Cardiomyopathy is a group of heart diseases with diverse etiologies in which the initial and predominant cause is damage to the myocardium (heart muscle). Subsequently, they may progress to heart failure.

I can be:

• Primary - or idiopathic, meaning without a known cause.

Secondary to other conditions:

• Metabolic disorders: nutritional, endocrine, etc.
• Systemic diseases: collagen diseases, neoplasms, etc.
• Neurological, neuromuscular, muscular disorders: dystrophies, ataxias, myopathies, etc.
• Toxic diseases: medicinal, biological
• Physical agents: radiation

Cardiomyopathies are divided into:

• Obstructive and non-obstructive hypertrophic cardiomyopathy
• Restrictive cardiomyopathy
• Dilated cardiomyopathy

A. Hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy is a myocardial disorder of unknown cause (in most cases genetic), characterized by thickening (hypertrophy) of the ventricular myocardium and significant disorganization of the myocardial (heart muscle) architecture.

Hypertrophy can be symmetric, evenly distributed, or asymmetric, affecting in particular the interventricular septum (the wall separating the two ventricles) and causing obstruction in the outflow pathway of the left ventricle, resulting in obstructive hypertrophic cardiomyopathy.

Symptoms range from no symptoms, to fatigue with progressively less exertion, dyspnea (shortness of breath), angina pectoris, dizziness, syncope (loss of consciousness), palpitations, fatigability.

Suspicion is raised on the basis of physical examination: the presence of a systolic murmur, ECG examination (which is altered in about 80-90% of cases). The diagnosis is made by cardiac ultrasound. The degree of thickening of the ventricular myocardium is determined, as well as the degree of obstruction in the left ventricular outflow tract (very important elements for therapeutic decision).

In patients diagnosed with hypertrophic cardiomyopathy, it is absolutely necessary to examine family members (parents/children/ siblings), as the condition is predominantly genetically inherited.

The course of the disease is variable and unpredictable, with a mortality rate of about 3-4% per year. Death is generally sudden, due to rhythm disturbances (ventricular fibrillation).

Factors predisposing to sudden death are:

Majori:

• History of cardiac arrest
• Proven unsustained/sustained ventricular tachycardia ECG, Holter ECG etc.
• Family history of sudden death
• Unexplained syncope (loss of consciousness)
• Ventricular wall thickness over 30 mm (determined echocardiographically)
• Abnormal drop in blood pressure with exercise

Possible:

• Atrial fibrillation
• Myocardial ischemia
• The degree of obstruction in the left ventricular outflow tract - measured echocardiographically or by cardiac catheterization
• Excessive (competitive) effort

The treatment is:

• Medications: beta blockers, antiarrhythmics
• Interventional: percutaneous alcohol septal artery embolization
• Surgical: septal myomectomy, mitral valve replacement
• Bicameral pacemaker implant: in certain situations

All patients over the age of 40 diagnosed with hypertrophic cardiomyopathy, episodes of retrosternal pain, or risk factors for ischemic heart disease require coronary angiography.

B. Dilated cardiomyopathy

It is a condition characterized by enlargement of the left and/or right ventricle. It may be due to the progression of other cardiac diseases: ischemic heart disease with or without myocardial infarction, valvular damage, congenital cardiomyopathies, hypertension, other non-cardiac diseases: neurological, inflammatory (collagen diseases, autoimmune, etc), infectious (viral, bacterial, fungal, parasitic, etc), metabolic (diabetes mellitus, endocrine, nutritional deficiencies), toxic (alcohol consumption, medication, drugs, etc), or it can be idiopathic (without a known cause).

Signs and symptoms may range from no signs and symptoms, to heart failure due to impairment of the function of the left side of the heart: left ventricle and left atrium (fatigue at progressively lower efforts and at rest, dyspnea - initial shortness of breath on exertion, then as the disease progresses, on daily efforts for maintenance or at rest, to acute pulmonary edema) and subsequently due to impairment of the right side of the heart: right ventricle and right atrium (fluid accumulation in the lower limbs, lungs, heart, abdomen, enlargement of the liver).

As the disease progresses, complications can arise, including:

• Systemic/pulmonary embolisms: the formation of blood clots, which get into the blood circulation and cause obstruction (clogging) of the cerebral arteries (with the formation of strokes), of the lower/upper limbs (acute lower/upper limb ischemia), or in other vascular territories;
• Arrhythmias: especially atrial fibrillation, supraventricular and ventricular extrasystoles, ventricular tachycardia, ventricular fibrillation;
• Sudden death.

Investigations

• ECG
• Cardiac ultrasound
• Coronary angiography
• Holter ECG

Treatment depends on the stage of the disease and involves a combination of both:

• Medications: beta-blockers, diuretics, converting enzyme inhibitors, digitalis, antiaggregant, statins, nitrates, anticoagulant (depending on the cause, the presence of complications and associated diseases);
• Cardiac defibrillator implant: preventing sudden death;
• Ventricular assist devices;
• Heart transplant.