Cardiovascular Disease Flashcards by Morgane Bennett

What are the normal heart rates for dogs and cats?

Dogs = 60-180bpm
Cats = 120-240bpm

How well did you know this?

Not at all

Perfectly

What are the main types of cardiac diseases we can check for?

Congenital cardiac disease
Acquired heart diseases
Arrhythmias

How well did you know this?

Not at all

Perfectly

Give examples of congenital cardiac disease.

Abnormalities of heart development in utero e.g.
Aortic stenosis
Pulmonic stenosis
Patent Ductus Arteriosus
Ventricular septal defect

How well did you know this?

Not at all

Perfectly

Give examples of acquired heart diseases in dogs and cats.

Dogs = myxomatous mitral valve disease / dilated cardiomyopathy / pericardial effusion
Cats = hypertrophic cardiomyopathy

How well did you know this?

Not at all

Perfectly

How can we diagnose heart disease?

History
Physical examination
Blood tests
Blood pressure
Electrocardiography (ECG)
Echocardiography
Thoracic radiographs

How well did you know this?

Not at all

Perfectly

What typical presentations in the history lead us to consider heart disease?

Incidental finding - heart murmur/arrhythmia
Exercise intolerance, weakness, syncopal (fainting) episodes
Heart failure (left-sided = difficulty breathing (tachypnoea/dyspnoea) / right-sided = difficulty breathing and/or distended abdomen)
Sudden death

How well did you know this?

Not at all

Perfectly

What are we looking for on physical examination?

Loss of body condition
MMs - colour/CRT
Jugular veins - visible/pulsation
Peripheral pulses - quality/regular/deficits
Respiratory rate - > 35-40 breaths/min
Heart auscultation
Lung auscultation

How well did you know this?

Not at all

Perfectly

What are we assessing on auscultation of the heart?

Heart rate
Rhythm - regular/irregular, gallop sounds
Pulse - quality/deficits
Heart murmurs - timing/point of maximal intensity/grading

How well did you know this?

Not at all

Perfectly

What are we assessing on auscultation of the lungs?

Respiratory rate
Adventitious sounds
Crackles

How well did you know this?

Not at all

Perfectly

What are the typical findings in heart failure?

Reduced cardiac output - weak peripheral pulses, tachycardia, pale MMs, prolonged CRT
Weakness, exercise intolerance, syncope
Heart murmur
Gallop sounds
Arrhythmias +/- pulse deficits
Congestion

How well did you know this?

Not at all

Perfectly

Describe left- and right-sided congestion.

Left-sided = lungs (pulmonary oedema, tachypnoea (> 40 breaths/min), dyspnoea)
Right-sided = systemic (distended peripheral veins, ascites (free fluid in abdomen), pleural effusion)

How well did you know this?

Not at all

Perfectly

What blood tests can we carry out?

Haematology (systemic diseases, anaemia)
Biochemistry (kidney values, electrolytes)
Cardiac biomarkers - cardiac troponin I (cTnI) / N-terminal pro-B-type natriuretic peptide (NT-proBNP)

How well did you know this?

Not at all

Perfectly

What is normal systolic blood pressure?

120-140mmHg

Consider effects of stress

How well did you know this?

Not at all

Perfectly

How do hypertension and hypotension indicate heart disease?

Hypertension = increased cardiac workload, can contribute to progression of disease
Hypotension = might indicate decompensated heart failure, < 80mmHg is concerning

How well did you know this?

Not at all

Perfectly

How do we use electrocardiography (ECG) to diagnose heart disease?

Further characterise auscultatory findings:
Bradycardia
Tachycardia
Irregular rhythm
Pulse deficits

How well did you know this?

Not at all

Perfectly

How can we use a Holter monitor (24hr ECG)?

To investigate intermittent arrhythmias
Clinical importance of arrhythmia - suspected cause of syncope/exercise intolerance, frequency + severity at home
Response to antiarrhythmic therapy

How well did you know this?

Not at all

Perfectly

How do we use echocardiography (cardiac ultrasound)?

Diagnose cardiac disease
Treatment options
Severity of disease and prognosis
Progression of disease
Response to treatment

How well did you know this?

Not at all

Perfectly

What are the indications for thoracic radiographs?

Cough
Dyspnoea
Tachypnoea

How well did you know this?

Not at all

Perfectly

What views do we use for thoracic radiographs investigating heart disease?

At least two views
Right lateral
Dorsoventral

What are we looking for on thoracic radiographs?

Congestive heart failure
Lung pathology
Cardiomegaly

Where may the narrowing of the vessels in stenosis occur?

Subvalvular (below valve)
Valvular
Supravalvular (above valve)

Describe aortic stenosis.

Subvalvular
Left ventricular hypertrophy (increased workload)
Left-sided congestive heart failure

Describe pulmonic stenosis.

Valvular
Right ventricular hypertrophy (increased workload)
Right-sided congestive heart failure

What clinical signs do we see of stenosis?

Can be asymptomatic
Arrhythmias
Exercise intolerance
Syncope
Congestive heart failure

How do we treat stenosis?

Beta blocker Balloon valvuloplasty (pulmonic stenosis) Standard treatment for congestive heart failure

What happens if fetal ductus arteriosus remains patent?

Blood flow from aorta to pulmonary artery Loud continuous murmur at left heart base Incidental finding / congestive heart failure

How do we treat patent ductus arteriosus?

Interventional closure (ductal occluder) Surgical ligation Congestive heart failure therapy

Describe a ventricular septal defect.

Most common location = upper septum (just below aortic valve) Usually asymptomatic Right-sided systolic murmur (small defect = loud murmur, large defect = soft murmur) Usually no treatment necessary / heart failure treatment Normal life expectancy if small defect

Describe myxomatous mitral valve disease.

Idiopathic - hereditary Small breed dogs e.g. Cavalier King Charles spaniels, Dachshunds etc. Adult onset Mitral / tricuspid valve Left-sided apical systolic heart murmur Slow progression (long asymptomatic period, incidental finding) May progress to left-sided congestive heart failure

How do we diagnose myxomatous mitral valve disease and what are we looking for?

Echocardiography Thickening of valve leaflets - regurgitation of blood, left atrial dilation, left ventricular dilation Prolapse of valve leaflets

Describe dilated cardiomyopathy.

Idiopathic - hereditary Large breed dogs - Dobermann, Great Dane, Newfoundland Adult onset Left apical systolic murmur (not always present) Long asymptomatic period

What does dilated cardiomyopathy cause and how does it progress?

Disease of myocardium - left ventricular dilation, decreased systolic function, arrhythmias Progression may be rapid - arrhythmias, sudden death, congestive heart failure

Describe pericardial effusion.

Large breed, adult dogs Causes = idiopathic, neoplasia, etc. Fluid in sac around heart compromises filling ('tamponade') - decreased cardiac output, right-sided heart failure

How do we treat pericardial effusion?

``` Pericardiocentesis (drainage): Mild sedation, left lateral recumbency Prepare area 3rd-8th intercostal space Large catheter Visualise window (echocardiography) ```

How do we differentiate between blood and pericardial fluid?

Check for clotting (should not clot like blood) Check PCV of fluid (lower than blood) Measure volume drained Collect samples (cytology = EDTA, culture = sterile tubes)

Describe hypertrophic cardiomyopathy.

Most common cardiac disease in cats Genetic causes, adult onset Exclude other causes of hypertrophy (hyperthyroidism, systemic hypertension) Increased myocardial thickness impairs filling in diastole

How can hypertrophic cardiomyopathy present?

(Right-sided) heart failure - pulmonary oedema, pleural effusion Incidental finding - heart murmur, gallop sound Aortic thromboembolism - sudden onset lameness, cold leg, peripheral cyanosis, pain

What can heart failure be due to?

Disease progression Decompensation of previously stable heart failure Development of impedance of cardiac filling, e.g. pericardial effusion

What do both left- and right-sided heart failure lead to?

Decreased cardiac output Tachycardia Weak peripheral pulses Slow CRT

How do cats differ when presenting with heart failure?

Cats may present with hypothermia and bradycardia.

How do we treat heart failure?

Furosemide (diuretic - decrease circulating volume) Minimise stress Oxygen Pimobendane (increases contractility - dogs) ACE inhibitor (vasodilator, anti-remodelling) Spironolactone (weak diuretic, anti-remodelling) Water must always be available

What are the signs of improvement in heart failure patients?

Decreased respiratory rate and effort Decreased heart rate Improved pulse quality Improved CRT

Give some examples of causes of bradycardia.

Sinus bradycardia Atrial standstill Atrioventricular blocks Sick sinus syndrome

Describe the 3 stages of AV block.

1st degree = slow conduction through AV node (longer gap between P and QRS) 2nd degree = non-conducted P waves (some P waves not followed by QRS) 3rd degree = atrial rate 200bpm, ventricular rate 40bpm (wide and bizarre QRS complexes)

Describe supraventricular tachycardia.

Originate from the atria | QRS complexes are narrow (similar to sinus complexes)

What is an example of supraventricular tachycardia?

Atrial fibrillation - heart rate 210bpm, irregular rhythm, no P waves

Describe ventricular arrhythmia.

Originate from the ventricular myocardium QRS complexes are wide and bizarre Ventricular tachycardia - heart rate 375bpm