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Clinical presentation of cardiac disease - Coggle Diagram
Clinical presentation of cardiac disease
Congestive signs - Left (increased heart filling pressure)
pulmonary venous congestion
pulmonary oedema
cough
often soft and moist (but sometimes sounds like gagging)
rare in cats
may produced blood tinged sputum
an enlarged left atrium (in absence of left sided heart failure) may contribute to coughing by mechanical dorsal compression of the trachea or mainstem bronchi, resulting in a cough of tracheal collapse
dogs that cough after drinking may have cardiac disease
may also be collapsing trachea, chronic trachietis, tracheobronchitis, laryngeal paralysis or other causes of dysphagia
identifying cause may be challenging
radiographs
echocardiograms
fluoroscopy
transtracheal washes
bronchoscopy
Response to furosemide
does not mean dog had heart failure, as furosemide has both anti-inflammatory and antitussive properties
most common cause of coughing in dogs with murmurs is respiratory disease.
Coughing is not caused by pulmonary oedema unless dog/cat is also tachypnoeic or dyspneic
tachypnoea
progresses to
dyspnoea
will occur whenever anything increased the amount of air that must be breathed in by animal
the usual cardiac cause in dog is left sided heart failure, which results in pulmonary oedema.
the usual cardiac cause in cat is right sided heart failure, which causes pleural effusion and left sided heart failure which causes pulmonary oedema
causes
acidosis
anaemia
CNS disorders
excitement/high altitude/pain/strenuous exercise
pericardial effusions
pleural effusions
primary cardiac diseases causing pulmonary oedema or pleural effusion
pulmonary oedema (noncardiogenic)
secondary cardiac diseases
thoracic wall problems e.g. fractured ribs
cats with hyperthyroidism
In patients with cardiac disease, can be accompanied by stridor (harsh, high-pitched respiratory sound)
or rhonchi (dry, coarse crackles)
can be accompanied by wheezing which is more typical of respiratory than cardiac problems
Paroxysmal
dyspnoea
dyspnoea comes and goes
associated with arrhythmias that cause either bradycardia or tachycardia
if improves with...
diuretics suggests left-sided heart failure
bronchodilators, antibiotics or steroids - suggests respiratory disease as cause
increased respiratory effort
orthopnea
dyspnoea when animal is lying down, but not when standing
associated with...
pulmonary oedema
pleural effusion
pericardial effusion
pneumothorax
diaphragmatic hernia
severe respiratory problems
pulmonary crackles
tiring
haemoptysis
uncommon in animals as they usually swallow their sputum
sign of severe pulmonary disease
cardiac causes include severe pulmonary oedema e.g. ruptured chordae tendinae
causes
acute/chronic bronchitis
chronic pulmonary granulomas
clotting disorders
Disseminated intravascular coagulopathy
lung abscesses
lung lobe torsion
oral/other neoplasia
pulmonary
embolism
fungal infection
neoplasia
respiratory foreign bodies
severe pneumonia
severe pulmonary oedema
trauma with severe pulmonary contusions
cyanosis
2ry right sided heart failure
cardiac arrhythmias
congestive signs - right (increased right heart filling pressure)
systemic venous congestion
causes increased central venous pressure
jugular vein distension
Hepatic +/- splenic congestion
pleural effusion
increased respiratory effort
orthopnea
cyanosis
ascites
seen more frequently in dogs with right sided heart failure due to acquired diseases (e.g. tricuspid regurgitation caused by chronic valvular heart disease, DCM, pericardial effusions, restrictive pericarditis) and congenital heart defects (e.g. tricuspid dysplasia, large ventricular septal defect, large atrial septal defect)
less common in cats and is usually caused by tricuspid dysplasia, occasionally seen with other problems e.g. DCM
large amounts puts pressure of the diaphragm -> tachypnoea or dyspnoea
if associated with right sided heart failure is usually protein rich (modified) transudate and accumulates slowly.
any time this occurs (even without murmur) right sided heart failure must be included in the differential diagnoses.
small pericardial effusion
subcutaneous oedema
cardiac arrhythmias
Low output signs
tiring
weakness/exercise intolerance
cardiac disease with myocardial dysfunction e.g. DCM
cardiac disease with obstruction to left ventricular outflow
sub aortic stenosis, hypertrophic obstructive cardiomyopathy
decreased arterial oxygen
e.g. pulmonary oedema, pleural effusion, or other pulmonary diseases
inadequate ventricular filling
arrhythmias
pericardial diseases
drug toxicities
severe anaemia/metabolic disease/respiratory disease/systemic disease
syncope
transient unconsciousness associated with loss of postural tone (collapse) from insufficient oxygen or glucose delivery to the brain
DIFFERENTIATE FROM SEIZURES
syncope often associated with exertion/excitement
tonic/clonic motion, facial fits and defecation not common in syncope
an aura, postictal dementia and near deficits generally not seen in dogs with cardiovascular syncope
Convulsive syncope
caused by hypotension/asytole
presents as seizure like activity/twitching
Test to determine cause
ECG recordings
during rest, exercise +/- after exercise
or after vagal manoeuvre
carotid sinus massage
ocular pressure
24h holter, implantable loop recording device
CBC and biochemistry
including glucose and electrolytes
Neuro exam
thoracic radiographs
echocardiography
cardiovascular
causes
bradyarrhythmias e.g. 2nd-3rd degree AV block
tachyarrhythmias e.g. ventricular tachycardia, atrial fibrillation
congenital ventricular outflow obstruction (pulmonic stenosis, sub aortic stenosis)
acquired ventricular outflow obstruction
e.g. pulmonary hypertension, hypertrophic obstructive cardiomyopathy, intracardiac tumor, thrombus
cyanotic heart disease
impaired forward cardiac output
e.g. dilated cardiomyopathy, myocardial infarction, severe mitral insufficiency
impaired cardiac filling
e.g. hypertrophic cardiomyopathy, intracardiac tumour, thrombus
cardiovascular drugs e.g. diuretics, vasodilators
neurocardiogenic reflexes (vasovagal, cough-syncope)
severe sub aortic stenosis
severe pulmonic stenosis
small dogs with severe mitral regurgitation that cough when excited
tetralogy of fallot
Pulmonary
causes
diseases causing hypoxaemia
pulmonary hypertension
pulmonary thromboembolism
Metabolic and haematologic causes
hypoglycaemia
hypoadrenocorticism
electrolyte imbalance (esp. potassium, calcium)
anaemia
sudden haemorrhage
neurological
causes
cerebrovascular accident
brain tumour
(seizures)
neuromuscular
disease
(narcolepsy, cataplexy)
Cough syncope ('cough drop')
fainting associated with coughing fit
some dogs with marked atrial enlargement and bronchial compression
can also stimulate a cough (often described as dry, hacking)
can be 1ry respiratory disease
pre renal azotaemia
cyanosis (from poor peripheral circulation)
cardiac arrhythmias
clinical exam
Signalment
common specific findings in a given breed
e.g. soft left basilar ejection murmur in normal Greyhounds and other sighthounds
larger horses more likely to develop atrial fibrillation
ponies more likely to have septal defects
Age
young animals often have congenital disease
older more likely to have acquired disease
large breed middle aged dogs more likely to have myocardial disease
small breed old dogs more likely to have primary valvular disease
mitral valve degeneration
sex
patent ductus arteriosus more common in females
dilated cardiomyopathy more common in males in some breeds, or occurs at an earlier age in males
cardiac disease is generally more prevalent in males than females
breed
a lot of congenital disease is breed or type as are a lot of the myocardial diseases
aortic stenosis in boxers, golden retrievers, german shepherds and newfoundlands
acquired dilated cardiomyopathy is found in certain larger breeds e.g. dobermans, old english sheepdogs and all giant breeds (some smaller exceptions e.g. cocker and springer spaniels)
Distance observation
attitude
posture
paresis
thromboembolism
Reasons that an animal will not lie down
diaphragmatic hernia
pneumothorax
severe pericardial effusion
severe pleural effusion
severe pulmonary oedema
severe respiratory disease
BCS
chronic weight loss in chronic heart failure
(cardiac cachexia)
problems that contribute to cardiac cachexia
ascites
cardiac medications causing anorexia and vomiting
electrolyte imbalance causing anorexia
increased energy use by the body
increased tumour necrosis factor
malabsorption
maldigestion
protein losing enteropathy
anxiety
can be due to respiratory difficulty
respiratory pattern
respiratory difficulty
flared nostrils
anxious
rapid breathing rate
increased respiratory effort
hyperpnea (increased depth of respiration)
hypoxaemia
hypercarbia
acidosis
Pulmonary oedema and other pulmonary infiltrates increases lung stiffness and rapid shallow breathing (tachypnoea) results as an attempt to minimise work of breathing.
prolonged, laboured inspiration
upper airway disorders (obstruction)
prolonged expiration
lower airway obstruction or pulmonary infiltrative disease (including oedema)
severely compromised ventilation
may refuse to lie down
sit with elbows abducted to allow maximal rib expansion
resist positioning in dorsal or lateral recumbency
orthopnea
cats with dyspnoea often crouch in sternal position with elbows abducted
open mouth breathing = severe respiratory distress
evaluate the peripheral circulation
mucous mebranes
oral, vaginal or prepuce mucosa can be evaluated
if oral mucosa pigmented can use conjunctival
pale
anaemia
peripheral vasoconstriction
poor cardiac output/high sympathetic tone
slow CRT (more than 2sec) is usually found in systolic failure, as opposed to anaemia
petechiae
platelet disorders
icterus
evaluate for haemolysis or hepatobiliary disease
injected, brick red
polycythemia
sepsis
excitement
cyanotic
pulmonary parenchymal disease
airway obstruction
pleural space disease
pulmonary oedema
right to left shunting congenital cardiac defect
hypoventilation
shock
cold exposure
methaemoglobinaemia
Differential cyanosis
reversed patent ductus arteriosus
head and forelimbs receive normally oxygenated blood, but caudal part of body receives desaturated blood via the ductus, which arises from the descending aorta
late finding in severe cardiac disease
Capillary refill time (CRT)
colour should return in 2 seconds
slower refill times
dehydration
decreased cardiac output
due to high peripheral sympathetic tone and vasoconstriction
normal in anaemic animals, unless hypo perfusion also present.
evaluate the systemic veins
esp jugular veins
should not be distended when animal standing and head in normal position
persistent distension
right sided CHF
e.g. tricuspid regurgitation, dilated cardiomyopathy
external compression of the cranial vena cava
heart base tumour
mediastinal mass
jugular vein or cranial vena cava thrombosis
pericardial disease
jugular pulsations higher than 1/3 of neck = abnormal
differentiate from carotid pulse wave transmission through adjacent soft tissues (esp. thin or excited animals)
occluded lightly below visible pulse and if disappears it is a true jugular pulsation
jugular pulse waves are related to atrial contraction and filling
visible pulsations
animals with tricuspid insufficiency (after first heart sound, during atrial contraction)
stiff and hypertrophied right ventricle
arrhythmias causes atria to contract against closed AV valves
Hepatojugular reflux
apply pressure to cranial abdomen as animal stands quietly - this transiently increases venous return
if jugular distends whilst pressure applied this is a positive (abnormal) test
evaluate the systemic arterial pulses
femoral arteries
compare both
if one side absent or weaker may indicate thromboembolism
fewer femoral pulses than heart beats indicates
pulse deficit
various cardiac
arrhythmias
induce this by causing heart to beat before adequate ventricular filling has occurred.
alternately weak than strong pulsations
myocardial failure
severe dilated cardiomyopathy
normal heart beat alternating with a premature beat
which causes reduced ventricular filling and ejection
pulsus alternans
exaggerated decrease in systolic arterial pressure during inspiration occurs in associated with
cardiac tamponade
pulsus paradoxus
abrupt pulses
mitral regurgitation
ventricular septal defects
Erratic pulses
atrial fibrillation
hypo kinetic pulses
heart failure
hypotension
hypovolaemia
sub aortic stenosis
Hyperkinetic pulses
aortic regurgitation
fear
fever
patent ductus arteriosus
along with a prolonged thrill at the heart base, high in the left axilla
severe anaemia
severe bradycardia
thyrotoxicosis
Only very advanced heart disease will cause weak pulses
evaluate the precordium (left and right chest wall over heart)
cardiomegaly or a space occupying mass can shift the precordial impulse to an abnormal location
decreased intensity of the precordial impulse
obesity
weak cardiac contractions
pericardial effusion
intrathoracic masses
pleural effusion
pneumothorax
usually strongest pulse during systole over area of left apex
a stronger right pericardial impulse
right ventricular hypertrophy
displacement of heart to right hemithorax
mass lesion
lung atelectasis
chest deformity
precordial thrill from very loud cardiac murmurs
Palpate/percuss for abnormal fluid accumulation
ascites
subcutaneous oedema
pleural effusion
auscultating heart and lungs
Other clinical signs associated with cardiac disease
PU/PD common in animals given diuretics or have concurrent disease e.g. renal disease
Oliguria occurs with severe left sided heart failure
haemoglobinuria found with caval syndrome of heart worm disease
cardiac drugs e.g. digitalis, diltiazem and mexiletine can cause ...
anorexia
vomiting
diarrhoea
regurgitation occurs with congenital vascular ring anomalies
right sided heart failure can cause intestinal oedema and a protein losing enteropathy resulting in diarrhoea
cats with cardiomyopathy can have haemorrhagic enteritis resulting from thromboembolism of gastric or mesenteric arteries
History
pet animals often show few signs of disease until failure intervenes, but working/sporting dogs may be compromised by minor disease
often dyspnoea disregarded by owners until disease advanced/life threatening
whereas coughing owners are more concerned with (irritated by)
animals with dyspnoea need aggressive diagnosis and care handling to avoid sudden death
Abdominal palpation
possibility of CHF
in cardiac failure, the fluid is usually modified transudate
moderate protein and cellular content
hepatomegaly
frequently found in CHF
pressure on liver may accentuate jugular distension in right sided cardiac failure (hepatojugular reflux)
dogs esp. GSDs with splenic neoplasia often present with recurrent episodes of collapse and show pallor and tachycardia
associated with recurrent intraabdominal haemorrhage
Auscultation
S1
Loud
thin chest wall
high sympathetic tone
tachycardia
systemic arterial hypertension
shortened PR intervals
muffled
obesity
pericardial effusion
diaphragmatic hernia
dilated cardiomyopathy
hypovolaemia/poor ventricular filling
pleural effusion
onset of systole on closure of the atrioventricular valves.
usually loudest heart sound and heard best over left apex
S2
increased intensity
pulmonary hypertension
closure of pulmonic and aortic valves
represents end of systole and will be loudest at left heart base
split S2 - can occur for example with pulmonary hypertension
Gallop sounds
S3 + S4 heart sounds occur during diastole
not normally audible in dogs and cats
audible S3 usually indicates ventricular dilation with myocardial failure
best heard over cardiac apex
may also be heard in dogs with advanced valvular heart disease and congestive failure
may be only auscultable abnormality in animal with dilated cardiomyopathy
(S3 is associated with end of rapid ventricular filling phase)
S4 associated with blood flow into ventricles during atrial contraction
audible S4 normally associated with increased ventricular stiffness and hypertrophy
e.g. hypertrophy cardiomyopathy or hyperthyroidism in cats
transient S4 gallop sometimes heard in stressed or anaemic cats
Du-Lub-Dup - can only characterise if S3 or S4 by recording a phonocardiogram (but this is not likely significant)
other transient sounds
systolic clicks
mid-late systolic sounds that are usually heard best over the mitral valve area
associated with degenerative valvular disease (endocardiosis)
mitral valve prolapse
congenital mitral dysplasia
an early systolic, high pitched ejection sound at left base
valvular pulmonic stenosis
other diseases that cause dilation of a great artery
Systolic murmurs
functional murmurs - left heart base, soft-moderate, decrescendo
'innocent' puppy murmurs
usually disappear by the time the animal is about 6m old.
physiological
anaemia
fever
high sympathetic tone
hyperthyroidism
marked bradycardia
peripheral arteriovenous fistulae
hypoproteinemia
athletic hearts
Aortic dilation e.g. with hypertension and dynamic right ventricular outflow obstruction are conditions associated with systolic murmurs in cats
mitral insufficiency - left apex (in area of mitral valve)
plateau-shaped (holosystolic timing)
with degenerative mitral valve disease, murmur intensity often related to disease severity
systolic ejection murmurs
left base
ventricular outflow obstruction
sub aortic or pulmonic valve stenosis
dynamic muscular obstruction
become louder as cardiac output or contractile strength increases
common in sighthounds, boxers and certain other large breeds
pulmonary stenosis - left base
Tricuspid insufficiency murmur is loudest at the right apex over the tricuspid valve
often accompanied by jugular pulsations
ventricular septal defects cause holosystolic murmurs
PMI usually at the right sternal border, reflecting the direction of the intracardiac shunt
a large ventricular septal defect may cause the murmur of relative pulmonic stenosis
may be present in apparently healthy cats
indicates the presence of
turbulent flow
within an area of the heart due to
disturbance to the normal laminar flow
of blood within heart and surrounding vessels
increased velocity of blood flow
increased volume of blood flow
reduction in blood viscosity
when there is regurgitation of blood across an insufficient valve
Systole
AV valves closed
Mitral and tricuspid insufficiency
Outflow valves open
aortic and pulmonic stenosis
aortic pressure > PA pressure
flow through PDA
LV pressure > RV pressure
flow through ventricular septal defect
Diastolic murmurs
diastole
outflow valves closed
aortic and pulmonic insufficiency
congenital malformation or degenerative aortic valve disease
Aortic insufficiency from infective endocarditis
AV valves open
Mitral and tricuspid stenosis (low pressure)
aortic pressure > pulmonary artery pressure
flow through patent ductus arteriosus
LV pressure approx equals RV pressure
no flow through VSD
Continous murmurs
Patent ductus arteriosus
loudest high at the left base, above the pulmonic valve area
S3 + S4 may be audible in normal large animals, but when audible in small animals are always indicative of an abnormality
S3= passive ventricular filling
S4= active ventricular filling as atria contract
presence of audible diastolic systolic sound implies ventricle is not filling normally (poor relaxation)
murmur description
timing/duration
intensity
location (point of maximal intensity)
Radiation
pitch
high pitch more likely to be ejection murmurs and low pitch may suggest regurgitant flow
shape
e.g.decrescendo with aortic regurgitation in horses
