02: Findings

T/F: a heart murmur means there is heart disease

FALSE

THE most common acquired heart disease in dogs

Myxomatous mitral valve disease

MMVD grade A

No clinical signs but dog/breed is at high risk

MMVD grade B1

Heart murmur with no or mild cardiac enlargement

MMVD grade B2

Heart murmur and cardiac enlargement but no history of CHF

MMVD grade C

C = congestion. Current or past clinical signs of CHF

MMVD grade D

D = death. Current or past clinical signs of CHF refractory to standard meds/doses

Definition of shock

Insufficient O₂ use or delivery to meet cellular demand

Two types of heart failure

Congestion and forward flow/pump failure

Cardiogenic shock

Forward flow/pump failure leading to inadequate O₂ delivery

Preload

The amount of blood present in the R ventricle at the diastole

Afterload

The pressure the L ventricle works against to eject blood

Contractility

Heart’s ability to eject the stroke volume of blood

T/F: cats with heart disease cough

FALSE, a coughing cat has lower airway dz until proven otherwise

Why do dogs cough with heart disease

If the heart disease is severe enough to compress mainstem bronchi

Diet associated with DCM

Grain free

6 perfusion parameters

• Pulse rate

• Pulse quality

• Distal extremity temperature

• Mentation

• MM color

• CRT

Types of normal rhythm for a dog

Sinus rhythm or sinus arrhythmia

Types of normal rhythm for a cat

Sinus rhythm ONLY

Heart sounds normally heard in small animals

S1 and S2

What are we hearing when we auscult S1

Closure of AV valves

What are we hearing when we auscult S2

Closure of semilunar valves

Which normal heart sound is the loudest

S1 (AV valves)

Gallop rhythm

When you can hear S3 and S4

What are we hearing when we auscult S3

Rapid ventricular filling phase; blood hitting a dilated LV

What are we hearing when we auscult S4

Blood flowing into ventricle right after atrial systole

Classic feline cause of a gallop rhythm

Hyperthyroidism

What causes a heart murmur

Turbulent blood flow

When do we most commonly hear murmurs

Systolic murmur, between S1 and S2

Physiologic murmur

Benign/innocent murmur not associated with heart disease

Causes of physiologic murmurs

• Anemia

• Kittens/puppies <6 mos

• Very fast heart rate in cats

When we auscult physiologic murmurs, where is it the loudest

Usually louder at the base

Physiologic murmurs are what grade

I-III

Classifications for murmurs

• Grade: I-VI

• Timing: systolic v diastolic

• Point of maximal intensity (PMI): apex or base

What is a pulse

The difference between systole and diastole

Things to evaluate when palpating a pulse

It should match the heart rate and should not be weak or bounding

What does it mean if a pulse is weak

Low systolic blood pressure

What does it mean if a pulse is bounding

There is high systolic or low diastolic blood pressure

Electrolyte abnormality associated with bad heart disease

Hyponatremia

Clin path abnormalities associated with late stage heart disease

• Kidneys: pre-renal azotemia, hyperphosphatemia, hypokalemia

• Hyperlactatemia