The causes are multiple and usually easily identifiable.
- Obstacle to the ejection of blood from the ventricle is increased "post office".
• a narrowing of the outlet orifice of the ventricle (aortic stenosis in the left ventricle and the right ventricle to pulmonary)
• additional hurdle, such as systemic hypertension or pulmonary hypertension.
The result: an enlarged heart, that is to say an increase in the thickness of the ventricular wall in question is not working well.
- An increase in the volume of blood in the ventricle during ejection. Is the increase of the preload:
• Eject the same time to the aorta and the left atrium in mitral regurgitation,
• Eject the same time to the aorta and the right ventricle in the inter ventricular communication
• filling of the left ventricle with blood that has been ejected and returns in the ventricle: it is the aortic insufficiency.
Consequence: the size of the left ventricular cavity expands. The right ventricle may also expand in the same conditions.
- A disease of the heart muscle and its contractile function. It is the ability to eject blood is reduced:
• Alteration of the quality of contraction due to the expectation of all the muscle fibers of the heart: cardiomyopathies with overall achievement of myocardial cells (primitive, Family ethyl, deficiency, infectious ...)
• Reducing the number of fibers involved in the contraction: myocardial and coronary insufficiency where some areas of the heart, temporarily or permanently, have become ineffective.
- Abnormalities of ventricular relaxation: in addition to those of the post office or the preload.
In terms of frequency, the main causes of heart failure are:
- A coronary artery disease with myocardial responsible for a more or less significant loss of contraction potential;
- High blood pressure, outflow obstruction of blood from the left ventricle.
What are the causes of heart failure ?
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