Heart disease is one of the leading causes of death in humans. But can our feathered friends also suffer from cardiovascular conditions? Let’s take a closer look at avian cardiology.
What is Heart Disease?
Heart disease refers to a range of conditions that affect the heart and blood vessels. In humans, common types of heart disease include:
- Coronary artery disease – buildup of plaque in the arteries supplying blood to the heart
- Heart attack – blockage of blood flow to the heart
- Arrhythmia – abnormal heart rhythm
- Heart failure – inability of the heart to pump enough blood to meet the body’s needs
- Congenital heart defects – problems with the heart’s structure from birth
Many of these conditions are linked to lifestyle factors like poor diet, lack of exercise, and smoking. However, heart disease can also be genetic or develop as a result of other health conditions.
Avian Cardiovascular Anatomy
Bird hearts have some important anatomical differences compared to mammalian hearts:
- They have 4 chambers – 2 atria and 2 ventricles. Mammals have 4 chambers too.
- They lack a coronary circulation. While mammals have blood vessels on the surface of the heart that supply oxygen and nutrients, birds do not. Instead, oxygen diffuses directly into the heart muscle from the air sacs.
- Red blood cells are oval rather than round, allowing the blood to keep moving in tiny capillaries.
- The heart rate is much higher, often over 300 beats per minute in small songbirds. Larger birds like ostriches have slower heart rates.
Despite the anatomical variations, the basic mechanics of blood flow through the heart are similar. Oxygenated blood from the lungs flows into the left atrium, then the left ventricle pumps it out to the body. Deoxygenated blood returns from the body into the right atrium, then the right ventricle pumps it to the lungs.
Common Avian Heart Diseases
Birds can develop many of the same conditions that affect the human cardiovascular system. Some common avian heart diseases include:
Atherosclerosis
A buildup of fatty deposits inside blood vessel walls. This stiffens arteries and restricts blood flow. More common in older birds and those with high cholesterol.
Cardiomyopathy
A disease causing the heart muscle to become enlarged, thickened, or stiff. This reduces the heart’s ability to pump blood properly.
Arrhythmias
Irregular heart rhythms. These may involve abnormal heart rates (too fast, too slow, or fluctuating) or a loss of synchronized contractions between the atria and ventricles.
Bacterial Infections
Bacterial diseases like psittacosis and streptococcosis can infect the endocardium and heart valves. This causes inflammation and damage.
Heartworm Infection
Infestation of the arteries and heart with heartworms. More common in wild birds but can occur in captive birds exposed to mosquitos carrying the parasite.
Congenital Defects
Abnormal development of the heart before hatching or birth. Examples include septal defects (holes in the dividing wall between heart chambers).
Nutritional Disorders
Vitamin deficiencies and imbalances involving calcium, vitamin E, selenium, and other micronutrients can weaken heart muscle.
Toxicity
Ingestion of heavy metals like zinc and lead may damage heart tissue or alter heart rate and rhythm.
Signs of Heart Trouble in Birds
Birds often hide their illnesses very well. But some signs that may indicate heart issues include:
- Lethargy, weakness
- Difficulty breathing, rapid breathing
- Exercise intolerance
- Blue discoloration of skin, wattle, beak, or nails (cyanosis)
- Loss of appetite, weight loss
- Distended abdomen or swelling around the heart (heart enlargement)
- Fainting or sudden death
Diagnosing Cardiac Disease in Birds
Various diagnostic tests can check for heart problems in birds:
- Physical exam – listening to the heart and lungs with a stethoscope, feeling the abdomen for organ enlargement
- Lab tests – to assess minerals, proteins, blood cell counts, etc.
- Radiographs (x-rays) – to visualize the size and shape of the heart
- Electrocardiogram (ECG) – to evaluate heart rhythm
- Echocardiogram – ultrasound imaging to examine the heart’s structure and function
- Cardiac catheterization – inserts a thin tube into the heart to measure pressures and collect blood samples
Catching heart problems early allows for quicker treatment intervention.
Treating Cardiac Disease in Avian Patients
Options for treating heart disease in birds may include:
- Medications – drugs like diuretics, ACE inhibitors, beta blockers, anti-arrhythmics
- Supplements – coenzyme Q10, carnitine, taurine, antioxidants
- Diet changes – low salt diet for congestive heart failure
- Surgery – pacemaker implantation, repair of septal defects
- Electroshock – for certain arrhythmias
The prognosis depends on the specific condition, its severity, and how early treatment begins. Regular check-ups are important to monitor chronic cardiac disease. Managing controllable risk factors such as obesity can also promote cardiovascular health.
Protecting Your Bird’s Heart
Here are some tips for keeping your bird’s heart healthy:
- Annual vet exams to screen for problems
- A balanced, nutritious diet low in fat and sodium
- Regular exercise by allowing supervised out-of-cage flight time
- Maintaining ideal body weight to avoid obesity
- Reducing stress through proper handling, socialization, and positive reinforcement training
- Providing large enough cage space and enrichment
- Avoiding toxins like heavy metals, cigarette smoke, pesticides
- Controlling infections and parasites
- Ensuring normal mineral levels like calcium, iodine, selenium
The Bottom Line
Heart disease does occur in many species of birds, especially geriatric birds and those predisposed to obesity, poor nutrition, or sedentary lifestyles. Some birds may be genetically prone to cardiac issues as well. By providing attentive care and bringing birds for regular check-ups, owners can maximize their chances of catching any heart abnormalities early when they are most treatable. With proper treatment and supportive care, birds with heart disease can enjoy good quality of life for many years.
