Taking care of the heart of your heartbeat

Dr CS Arun
There’s no second thought that your pet is your heartbeat. But the modern-day lifestyle brings a lot of stress that may lead to cardiac problems in dogs. Know more about pulse of canine cardiology and how you can safeguard your pooch’s loving heart! – by Dr CS Arun
Cardiac ailments in dogs are diagnosed more often now-a-days, thanks to advanced diagnostic tools. About 10-15 percent of the diseases in dogs appear to be pertaining to the heart. Of these, about 5 percent are congenital diseases (a condition that’s present from birth). Some of the most common ones are – persistent ductus arteriosus, pulmonary stenosis, aortic stenosis, persistent right aortic arch, ventricular septal defect, tetralogy of fallot, atrial septal defect, etc. Other 95 percent are acquired ones like valvular insufficiency, dilated cardiomyopathy, arrhythmias, heartworm infestation, etc. Genetically, small breeds like Cocker Spaniel, Pomeranian, Schnauzers seem to be more prone to valvular diseases. Valvular diseases are the ones in which one or more valves of the heart are damaged. Large breeds like Great Danes, Labradors, Irish Wolf Hounds and Dobermans are more commonly affected with myocardial diseases. These are acquired or hereditary disease of the heart muscle. Senior, male, and obese dogs are more prone to heart diseases.

Do your part & protect your pooch’s heart

Obesity due to improper feeding and inadequate exercise leads to high blood pressure, atrial hypertension and left ventricular hypertension. Nutritional deficiencies of protein, fat, vitamins, minerals and trace elements increase the work load on the heart leading to various cardiovascular ailments. In genetically predisposed breeds, chronic mitral valve disease leads to congestive heart failure and dilated cardiomyopathy.Many metabolic diseases and parasitic infestations may also cause heart ailments.

Symptoms that scream heart problem

Clinical signs observed in cardiac patients are exercise intolerance, cough, dyspnoea–difficulty in breathing, orthopnoea – shortness of breath, tachypnoea – rapid breathing, weight loss, muscle wasting, lethargy, anorexia, reluctance to sit. Sometimes these signs can indicate other diseases. That’s why it is recommended that you get in touch with your vet at the earliest. With proper diagnosis, the possibility of other ailments will be ruled out and proper medication for corresponding heart disease can begin.

Diagnosis – beginning of remedy

Diagnosis is done by assessing your pet’s history and clinical signs. Physical examination, electrocardiography, echocardiography, thoracic radiography and biochemical tests are also done to detect other diseases causing cardiac ailment and demonstration of cardiac biomarkers.

Hale & hearty with right treatment
The patient has to be assessed to stage the cardiac ailment to initiate proper treatment. Make sure a heart check-up is part of routine check-up for your pets. And if your dog is old, has had a history of heart problems, or has diabetes, then it becomes all the more important for regular heart check-ups. Asymptomatic heart disease is common in small dog breeds. The vet might do radiography to obtain vertebral heart score, measure blood pressure, and do echocardiography as part of the treatment. If the heart size is normal, there is no need for any treatment. Repeat imaging every year. But if there is cardiomegaly and systemic hypertension, your vet might suggest some lifestyle changes like – restricted diet, less sodium intake, and addition of supplements to your pet’s routine.

Management of cardiac diseases

Triaging of cardiac emergencies is to be done through observation of –
Mucous membranes

• Pink- normal PCV and adequate perfusion
•  Pale- anaemia or shock
•  Cyanosed- hypoxemia

Capillary refill time

• 1-2 seconds- normal perfusion
•  >2 sec- poor perfusion/peripheral vaso constriction
•  <1 sec- fever/heatstroke/shock

Heart rate

•  60-120 bpm normal cardiac output
•  <60- low cardiac output/poor perfusion/arrythmia/metabolic

disease

•  >180-compromised diastolic filling/shock/pain/arrhythmia

Pulse rate and quality

• Strong and synchronous with heart beat- normal
•  Irregular- arrhythmia
•  Bounding- compensatory state of shock
•  Weak or absent- cardiac output/peripheral vasoconstriction/low pulse pressure/thromboses

Level of consciousness

• Alert & responsive- normal neurological and metabolic state
•  Depressed- low perfusion/other illness
•  Stupor- neurologic or metabolic derangement
•  Comatose or seizure- neurologic or metabolic derangements

Level of pain

• Vocalisation or aggression- pain delays healing

ABC of heart ailments
Sequence of emergency measurements to be adopted is called ABC, i.e., airways, breathing and circulation reparative measures.

A- Complete or partial obstruction of airways should be relieved manually or with suction. Intubation or tracheostomy may be done and oxygen administered. If needed, sedatives can be used.

B- Breathing compromise is reflected as increased rate and effort of breathing. On auscultation, muffled lung sounds may be heard. In extreme case, oxygen administration has to be done.

C- Circulatory compromise may be assessed through checking heart rate, mucous membrane pallor, capillary refill rate, rectal temperature, pulse quality and level of consciousness. Persistent tachycardia (heart rate over 100 beats per minute) is the sign of reduced perfusion. Goal of treatment is to deliver oxygen to the tissues.
 
How to differentiate between heart disease and respiratory disease?

Signs & symptoms        Cardiac disease            Respiratory disease
Duration                       Weeks – months              Months – years
Progression                         Rapid                                  Slow
Exercise intolerance              +                                          –
Body type                         Normal/ thin                        Obese
Sinus arrhythmia                    +                                          –
Heart rate                        Tachycardia                           Normal
Cardiomegaly                       Left                                      Right
Gas in abdomen                 Rare                                    Frequent
PCV                                 Normal/low                           Normal/ high
Cough                             Moist/soft                                Dry/ harsh
Femoral pulse               Weak                                           Normal
Cyanosis                        Short lived                                 Prolonged
Response to diuretics  Good                                           Minimal
Healthy lifestyle choices, the right kind of diet, and proper medication will help manage heart problems in your pet!

(Dr CS Arun, MVSc, runs My Pet Hospital in Mysore which provides total pet care under one roof)