Heart murmur in pets

Heart murmur in pets is an abnormal sound heard during auscultation (listening with a
stethoscope) that indicates turbulent blood flow within the heart. It is a common finding in both
dogs and cats and can range from harmless to a sign of serious heart disease.
What is a Heart Murmur?
– An abnormal sound caused by abnormal blood flow through the heart valves or chambers
– Usually graded on a scale from I (soft) to VI (loud) based on intensity
Causes of Heart Murmurs in Pets
1. Innocent or Physiologic Murmurs:
– No underlying heart disease
– Common in young, small, or active animals
– Usually soft and short-lived
2. Pathologic Murmurs (indicating heart disease):
– Valvular disease:
– Mitral or tricuspid valve insufficiency (common in small breeds)
– Aortic or pulmonic stenosis (narrowing of valves)
– Dilated cardiomyopathy:
– Enlarged chambers with abnormal flow
– Congenital defects:
– Patent ductus arteriosus (PDA), ventricular septal defects (VSD)
– Endocarditis or infective processes

Signs and Symptoms
– Many pets with murmurs are asymptomatic
– In advanced disease:
– Coughing
– Exercise intolerance
– Fatigue or weakness
– Difficulty breathing or coughing
– Fainting or collapse

Diagnosis
– Physical exam: auscultation to identify the murmur’s timing (systolic, diastolic), location, and
grade
– Further tests:
– Chest radiographs (heart size, pulmonary changes)
– Echocardiography (ultrasound) to evaluate structure and function

– Blood pressure measurement
– Electrocardiogram (ECG) if arrhythmias are suspected
Management
– No treatment needed for innocent murmurs but regular monitoring
– Treat underlying heart disease:
– Medications (e.g., ACE inhibitors, diuretics, pimobendan)
– Lifestyle adjustments (restricted activity in severe cases)
– Monitor regularly for progression or development of clinical signs

Prognosis
– Varies depending on the cause and severity
– Innocent murmurs generally have a good prognosis
– Heart disease requires ongoing management and monitoring
Summary
A heart murmur is a common finding in pets and can be benign or a sign of underlying heart
disease. Early detection, diagnosis, and appropriate management are crucial for the best
outcome.