It is inaccurate to classify heart failure as a disease or an exact diagnosis. It can be defined as a condition complicated malfunctioning of the heart causes an inability of the cardiovascular system to ensure sufficient flow of blood. Particular restricted and precise mechanisms exist, through which diseases of the heart can lead to the cardiovascular system malfunctioning. Thus, the symptoms that arise due to failure of the heart are also limited and specific.
Any heart that doesn’t have the capability to contract properly is assumed to be a failing heart. In most cases, dogs that suffer from heart disease resulting in abnormal growth of the chamber or thicker walls are said to have a failing heart. However, the body is typically able to balance the abnormality using alternative means. Due to this reason, the dog doesn’t display any signs and cannot be said to be suffering from congestive heart failure or heart failure.
Heart failure occurs when the flow of blood is inadequate in supplying body parts with sufficient oxygenated blood necessary for optimal function. Based on the extent of severity, symptoms of a failing heart might flare up when the dog is resting, during mild physical effort, or during modest or intense exercise.
Congestive failure of the heart and heart failure are health terms that are used to describe a condition where a dog displays symptoms associated with intricate relations linking the blood vessels and a failing heart.
Congestive heart failure is where blood accumulates in organs, especially the lungs and major organs, thus resulting in the packed organs to operate unusually, become engorged with blood and fluid.
Heart failure usually involves either systolic or diastolic dysfunction. Diastolic dysfunction is where there isn’t adequate blood to fill the heart before pumping. In systolic dysfunction, the heart isn’t strong enough to pump out sufficient blood. Both these conditions result in inadequate circulation.
Types of Heart Failure
It is possible to categorize heart failure into four practical classifications. These are systolic myocardial failure, volume overload, obstruction to cardiac inflow and pressure overload.
Systolic myocardial failure is classified as a general decrease in the contraction capability of the cardiac muscle. It creates reduced wall motion as the ventricles contract, and if there is considerable reduction, it becomes quite difficult to maintain normal flow of blood. This condition can be diagnosed with the aid of an echocardiography (ultrasonography). Systolic myocardial failure may be the result of electric shock, trauma, drugs or poisons infection, heat stroke, or tumours, though there are cases in which the cause is not known.
Volume overload is a category of heart failure that flares up whenever there is any disease that elevates the volume of blood in the ventricle(s), resulting in excess blood flow. Ultimately, this can create symptoms of congestive heart failure. Diseases that bring about volume overload heart failure are valve defects e.g. degenerative valve disease of the atrioventricular valves, patent ductus arteriosus, ventricular septal defect, hyperthyroidism and anaemia.
Heart failure that comes from the impediment to cardiac inflow could be a result of a drop in flow of blood. Causative factors could be outer force being exerted on the heart e.g. fluid in the membrane enclosing the heart, physical irregularities of parts of the heart, and malfunction of the diastole leading to a rigid ventricle and decreased ventricular filling.
Failure of the heart due to pressure overload is usually a consequence of a long-term rise in stress exerted on the wall of the heart as it contracts. Such actions could be a consequence of the impediment of blood flow from the heart or elevated blood pressure right through the body or even within the lungs’ arteries.daptation Of The Body To Heart Failure
Adaption Of The Body To Heart Failure (Compensation)
No other system is responsible for maintenance of regular blood pressure and flow of blood, other than the cardiovascular system. When there is heart disease, precise mechanisms are put in place by the body to try to stabilize such operations to counteract the harmful effects of the disease on the body. For example, in an animal suffering from dilated cardiomyopathy, the flow of blood is lessened by the heart’s poor contraction ability. This creates low blood pressure as a reduced amount of blood is pumped per contraction. The body balances via the sympathetic nervous system so as to boost the heart muscle’s ability to contract and to raise the heart rate. Such reactions elevate cardiac productivity and blood pressure. However, long-term utilisation of the sympathetic nervous system for such purposes harms the cardiac muscle, together with other organs. This damage consequently lowers the capacity of the cardiac muscle to pump and results in a surge of actions, including the discharge of a number of hormones that cause greater increase in blood volume and flow. For pets that have severe congestive heart failure, blood volume can rise as much as 30% above normal. Ultimately, continual heart muscle failure and long-term release of such hormones, as the body tries to control blood flow leads to sustained heart muscle failure. Flow of blood gets compromised more with elevated symptoms of congestive heart failure.
Symptoms of Heart Failure
Symptoms linked to heart failure rely on the reasons for the said condition together with the heart cavity affected. With respect to congestive heart failure of the left side, symptoms are related to a build-up of pressure inside the vessels that are responsible for the left ventricle receiving blood. Fluid in the lungs, coughing, and trouble breathing are the most frequent symptoms. A lot of dogs with left-sided congestive heart failure lose consciousness because of lack of blood flow to the brain. A reduced heart rate, low blood pressure and collapsing are also other consequences related to this condition.
Congestive heart failure of the right side causes elevated pressure within the blood vessels of the right ventricle, the veins and capillaries of the body. This may result in fluid accumulation in the stomach, the limbs and the chest cavity.
A condition known as biventricular failure commonly crops up when the left and right ventricles do not function correctly, for example in dogs that have cardiac muscle failure due to poisoning or an enlarged cardiomyopathy.
It is possible for a dog to display symptoms of the two types of congestive heart failure at once, though in most cases, symptoms of one will surpass the other.