Dilated cardiomyopathy

Heart with DCM (left), and a normal sized heart (right), on the X-ray

Classification according to ICD-10
I42.0	Dilated cardiomyopathy
ICD-10 online (WHO version 2019)

The dilated cardiomyopathy (DCM) is a pathological enlargement (dilatation) of the heart muscle , especially of the left ventricle. A systolic pumping error leads to a progressive loss of ejection performance . In addition, there is usually a disorder of the diastolic function (diastolic heart failure).

The disease is also known in veterinary medicine, but there it is mostly hereditary. See Dilated Cardiomyopathy (veterinary medicine)

causes

A distinction is made between primary (congenital) forms of cardiomyopathy and secondary forms that are the result of underlying diseases. Many genetic defects are known for the primary form, some of which can also cause other heart muscle diseases such as hypertrophic cardiomyopathy . The secondary form can have the following causes:

Rhythmogenic: a persistent rapid heart rhythm disturbance such as tachycardial atrial fibrillation ( tachycardiomyopathy )
Infectious: Viruses ( coxsackie virus , influenza viruses , adenoviruses , ECHO viruses ), bacteria ( staphylococci , enterococci , Borrelia burgdorferi ), fungi or protozoa ( toxoplasmosis , Chagas disease )
Toxic ( alcohol , anthracyclines , phosphorus , drugs)
Ischemic (recurrent heart attacks , microangiopathy )
Metabolic ( Beri-Beri , malnutrition )
Immunological ( systemic lupus erythematosus , panarteritis nodosa , progressive systemic sclerosis , dermatomyositis )
Endocrine ( hypothyroidism , hyperthyroidism , pheochromocytoma , acromegaly )
Valvular : cardiac dysfunction with advanced vitia
Neuromuscular: Duchenne muscular dystrophy , Becker muscular dystrophy, myotonic dystrophy Curschmann-Steinert

Chest x-ray of a man with pronounced dilated cardiomyopathy

Symptoms / diagnosis

The focus is on the symptoms of heart failure (especially shortness of breath) by reducing the ejection fraction of the left ventricle to up to 30 percent. Despite the increase in the end-diastolic volumes of the four heart cavities, the cardiac output is reduced . The dilation of the heart results in relative mitral regurgitation and tricuspid regurgitation . At the end of the diastole, a third heart sound occurs due to the contraction of the atria, whereby a gallop rhythm is perceived during auscultation . The pulse amplitude ( pulse pressure ) is small.

EKG

In the ECG you can often find a left bundle branch block and signs of enlargement of the left ventricle. There is often atrial fibrillation with absolute arrhythmia.

Imaging

Heart with mild DCM (left), and a normal heart (right) on cardio MRI

The heart shadow is widened in the chest x-ray . In echocardiography and magnetic resonance imaging , one sees an enlargement of the ventricles and the atria. The wall of the left ventricle is usually thinned, the left ventricle is spherically shaped and less mobile on all sides (contractile).

The ejection fraction is reduced. The distance between the anterior mitral leaflet and the septum is increased. Often there is mitral valve regurgitation and tricuspid valve regurgitation.

biopsy

In the heart muscle biopsy , one can differentiate between the types non-fibrosing , diffuse fibrosing and focal fibrosing . In addition, you can see narrow myocardial cells with large nuclei .

Complications

Important complications are heart failure, cardiac arrhythmias and thrombus formation in the enlarged heart cavities with the risk of a heart attack .

therapy

In the secondary forms, the causative disease is treated. Otherwise, cardiac insufficiency and cardiac arrhythmias are treated with medication with ACE inhibitors or sartans and with beta-receptor blockers . In addition, prophylaxis of thrombus formation in the form of anticoagulation is indicated. A more recent therapeutic approach is myocardial regeneration with the help of autologous stem cell transplantation , the efficiency of which has yet to be proven in larger studies. If the disease progresses, a heart transplant or implantation of an artificial heart can be considered.

In veterinary medicine , the inodilator pimobendan is the first choice. In addition, the regularly encountered and is atrial fibrillation triggered (supraventricular) tachycardia by means of the also positive inotropic action Digitalis treated. ACE inhibitors and beta blockers are also used here.

literature

MR Taylor, E. Carniel, L. Mestroni: Cardiomyopathy, familial dilated . In: Orphanet Journal of Rare Disorders . tape 1 , issue 27, July 13, 2006, PMID 16839424 , PMC 1559590 (free full text).

Individual evidence

^ Cardiomyopathy . In: Phenotype Search: Genatlas. Université René Descartes, Paris, September 16, 2019. hereinafter referred to as “cardiomyopathy, dilated”; Retrieved January 16, 2012.
↑ A. Perrot et al .: Cardiac manifestations in muscular dystrophies . In: Journal of Cardiology . tape 94 , no. 5 , May 2005, pp. 312-320 , doi : 10.1007 / s00392-005-0232-3 .
↑ CM Schannwell et al .: Human autologous intracoronary stem cell transplantation for myocardial regeneration in dilated cardiomyopathy (NYHA stage II to III) . In: Journal für Kardiologie , 15, 2008, pp. 23-30

[1] Cardiomyopathy . In: Phenotype Search: Genatlas. Université René Descartes, Paris, September 16, 2019. hereinafter referred to as “cardiomyopathy, dilated”; Retrieved January 16, 2012.

[2] A. Perrot et al .: Cardiac manifestations in muscular dystrophies . In: Journal of Cardiology . tape 94 , no. 5 , May 2005, pp. 312-320 , doi : 10.1007 / s00392-005-0232-3 .

[3] CM Schannwell et al .: Human autologous intracoronary stem cell transplantation for myocardial regeneration in dilated cardiomyopathy (NYHA stage II to III) . In: Journal für Kardiologie , 15, 2008, pp. 23-30