History, PE, & Diagnostics for Cardiac Disease Flashcards
How can age help with diagnosing cardiac disease? What is unique in cats?
- YOUNG = congenital conditions most likely —> aortic stenosis, PDA, pulmonic stenosis
- OLD = acquired conditions most likely —> myxomatous valvular degeneration, DCM
HCM can occur at ANY age
What breeds of dogs most commonly develop DCM? Valvular degeneration?
DCM = large breeds —> Doberman, Irish Wolfhounds, Great Danes
VD = small breeds —> Poodles, Chihuahuas, CKCS
In what breeds of cats is HCM most common?
- Maine Coons
- Ragdolls
- British Shorthairs
- Sphynx
- Persians
- Chartreux
What is indicative of right-sided heart disease?
decreases flow from the body to the right side or from the right side to the lungs, so it backs up in the body (high venous pressure)
- ascites
- jugular distention
- enlarged liver
(rare in cats)
What is indicative of left-sided heart disease?
impairs blood flow out of the left side, so it backs up in the lungs (chest cavity in cats)
- cough
- dyspnea
- pulmonary edema
- syncope
- pleural effusion and aortic thromboembolism in cats
Why do cats get pleural effusion more commonly compared to pulmonary edema in cases of left-sided heart disease?
cats have poorer LA function nd increased RV dimensions
(can still get pulmonary edema!)
What are 4 times where a heart murmur is considered an issue?
- puppy or kitten - must differentiate from physiologic
- new murmur
- worsening murmur
- symptoms accompany murmur
What are some cardiac diseases that do not present with murmurs?
- HCM
- DCM
- effusions that muffle heart sounds
What is occult cardiac disease? Mild?
subclinical disease lacking signs
mildly enlarged heart causes a cough due to bronchial compression, but no other symptoms other than a murmur
What are some presenting complaints that can be associated with cardiac disease?
- coughing
- dyspnea
- tachypnea
- lethargy
- collapsing
NONSPECIFIC
What are the differences between acute, chronic, and intermittent symptoms that may be contributed to cardiovascular disease?
ACUTE = more likely cardiac in origin, often historic murmur
CHRONIC = less likely cardiac; coughing, but fine between episodes
INTERMITTENT = must rule out common cardiac origins —> pericardial effusion, pulmonary hypertension (exertional), arrhythmias - all with the ability to possibly resolve
What are 3 indications of end-stage cardiac disease?
- severe coughing in dogs
- dyspnea from pulmonary edema in dogs and cats (left sided)
- dyspnea from pleural effusion in cats - L > R
cats do NOT cough with cardiac disease
When do cats cough with “cardiac” disease?
heartworm —> spread to pulmonary arteries (mostly a lung disease)
Cardiac vs. primary airway disease - history:
What is syncope? What are some causes?
transient loss of consciousness and postural tone caused by decreased cerebral perfusion
- pulmonary hypertension
- heart failure
- hypotensive shock
- arrhythmias
- pulmonic stenosis
- low blood pressure
- drugs
- hypoglycemia
- vasovagal
How are temperature affected by heart failure?
often normal or low
What is the palpable pulse? How is it most commonly affected by heart failure?
perceived difference between systolic and diastolic pressures
- increased HR (> 150) with heart failure, fear, excitement, exercise, pain, fever
- decreased HR (< 60) with feline heart failure, sleep, excessive parasympathetic tone, conduction disturbances (AV block, cardiac disease)
Why should auscultated heart rate be compared to pulse rate?
gives a clue into beating inefficiencies —> blood is likely not getting where it needs to be
What are hyperkinetic and hypokinetic pulses?
large/strong —> abnormal distension common during exercise or anemia
small/weak —> obliterated by finger pressure and short due to poor LV stroke volume caused by DCM, shock, aortic stenosis, or pericardial effusion
What are waterhammer and alternating pulses?
strong pulse with sharp rise and fall in pressure indicative of marked variation between systolic and diastolic pressures —> severe anemia, AV shunts
marked difference from pulse to pulse —> arrhythmias
What is sinus arrhythmia? What is the most common cause?
regularly irregular arrhythmia caused by a gradual increase and decrease with respiration and inhalation (decreases with exhale)
high vagal tone —> NOT heart failure or pathologic in dogs, but animals in heart failure are unable to do this
What is indicative of a pathologic arrhythmia?
irregularly irregular or regular with premature beats
- atrial fibrillation
- frequent VPCs
How does breed commonly affect the degree of murmur?
SMALL BREEDS = typically have loud murmurs Grade III or larger + valvular disease
LARGE BREEDS = typically have softer murmurs, often caused by DCM
(young dogs in CHF due to congenital disease typically have significant murmurs)
Why is it important to assess mucous membranes and CRT in patients with cardiovascular disease?
can cause anemia, hypotension, and poor perfusion = cyanosis
- could be a reverse PDA (R to L)
How can cardiovascular disease affect the mucous membranes?
- pale/grey/muddy = fear, hypoxia, shock, poor perfusion, anemia
- cyanotic = hypoxia, left heart failure, end-stage respiratory disease, airway obstruction
- slow CRT = decreased LV output or peripheral vasoconstriction
How can cardiovascular disease affect respiratory rate and effort?
increased rate and effort = key feature to monitor improvement or worsening
What 3 respiratory sounds can be heard with cardiovascular disease? What sound is typically considered a respiratory cause?
- harsh lung sounds - common with CHF due to increased effort needed to breath with the interstitial fluid dampening expansion of airways
- muffled lung sounds - effusion blocks sound
- crackles - alveoli opening due to severe pulmonary infiltrates (dyspneic with heart disease)
wheezes
How does right-sided heart disease affect the cardiovascular system?
increases venous pressure
- right-sided failure
- tricuspid disease
- pulmonary hypertension
- caval syndrome
- pericardial disease
- volume overload
- cranial mediastinal mass
What cardiovascular cause is related to ascites? What are some rule outs?
right-sided disease
- hemoabdomen
- lymph buildup
- uroabdomen
- peritonitis
- pregnancy
- hyperadrenocorticism
- splenomegaly, other organomegaly
What is cardiac cachexia? What typically exacerbates this disorder?
loss of muscle/lea body mass due to heart failure associated with shortened survival time in dogs —> end-stage, negatively impacts appetite and mobility
protein restricted diet
What is an apex beat? Where is it normally found? What does it mean if it’s shifted?
area near the mitral valve where the heartbeat is strongest —> 5-6th ICS on the left in the mid ventral third of the thorax
- CRANIAL = masses, hernias
- CAUDAL = anterior thoracic masses
What is a PMI? Thrill?
point of maximal intensity —> location where murmur is heard loudest
soft vibration from severe turbulence (where the PMI is)
Dog, cardiovascular exam:
What 2 other extra-cardiac parts of the physical exam can indicate significant heart disease?
- THYROID - hyperthyroidism is associated with hypertension in cats
- RETINA - hemorrhage and detachment associated with hypertension
What are the 4 heart sounds?
- S1 = closure of AV valves, opening of semilunar valves; louder, faster, lower pitched LUB (QRS wave)
- S2 = closure of semilunar valves, opening of AV valves; softer, shorter, higher pitched DUB (just after T wave)
- S3 = rapid ventricular filling (abnormal to hear in small animals)
- S4 = atrial systole, late ventricular filling (abnormal in small animals)
What are the systolic and diastolic intervals?
time between S1 and S2
time between S2 and S1 (usually longer than systolic)
Heart sounds:
What does a muffled heart sound indicate?
obstruction to sound
- pericardial/pleural effusion
- fat
- pneumothorax
- masses
What is a diastolic beat?
“gallop” - abnormal heart sound occurring in 3 sounds in each heartbeat
(NEVER normal in small animals, more commonly heard in cats)
What does it mean if S3 and S4 are heard?
S3 = rapid ventricular filling due to increased LA pressure (HCM!)
S4 = increased atrial constrction due to poor LV compliance so the AV valve snaps
(HCM, DCM, hypertension)
(if HR is >160 bpm, it is impossible to tell with naked ear)
What is a cardiac murmur?
turbulent blood flow —> not always pathologic
What 3 things does turbulent flow depend on? What greatly increases risk of turbulence?
- viscosity - lower viscosity due to anemia or hypoproteinemia
- velocity - tachycardia
- density and width of path
change in radius (stenosis)
When do systolic murmurs occur?
between S1 and S2 (most common)
- holosystolic = end of S1 to beginning of S2 (VSD, mitral/tricuspid valve regurgitation)
- pansystolic = beginning of S1 to end of S2
When do diastolic murmurs occur?
between S2 and S1
- rare, but indicative of aortic or pulmonary stenosis or regurgitation
What is a continuous murmur?
murmur occurring during both systole and diastole, which sounds like machinery (washing machine murmur) = PDA
What are the 6 grades of heart murmurs?
- focal, intermittent, may change with HR or phase of respiration, barely audible
- focal, consistently present despite changes in HR or respiration
- resonates over multiple valves, occasionally heard over both sides, moderately loud
- resonates over every valves, heard on both sides, loud
- very loud, heard all over, thrill present, still needs stethoscope
- same as above, but can be hear without stethoscope
What does a left and right apical systolic murmur indicate?
LEFT APICAL SYSTOLIC = mitral regurgitation (CVD, DCM, valves dysplasia)
RIGHT APICAL SYSTOLIC = tricuspid regurgitation (CVD, valve dysplasia, pulmonary hypertension, heart worm disease/caval syndrome)
What does a left basilar continuous murmur indicate?
left to right shunt
- most likely PDA
What do left basilar systolic murmurs indicate?
flow through aorta or pulmonary artery
- physiologic if II/VI or less
- loud = SAS or pulmonic stenosis
What do left basilar diastolic murmurs indicate?
aortic regurgitation
- endocarditis
- CVD (horse)
What commonly causes sternal systolic murmurs?
ABNORMAL in dogs, common in cats with VSD —> can be easily created by pressing on the sternum
In general, louder murmurs are more likely to be pathologic? What are 2 major exceptions?
- cardiomyopathies - murmurs not always present; DCM may develop a I-III/VI left apical systolic murmur
- atrial septal defects - soft I-II/VI left basilar systolic murmur
What are the 4 types of murmur pitches?
- crescendo = gradual increases to a peak intensity (subaortic stenosis, pulmonic stenosis, VSD)
- decrescendo = gradually tapers off from an initial peak (subaortic stenosis, pulmonic stenosis)
- crescendo-decrescendo (diamond) = builds up to a peak intensity and tapers off (subaortic stenosis, pulmonic stenosis, VSD)
- plateau = equal intensity (mitral or tricuspid regurg)
What are the 7 S’s of innocent murmurs?
- SYSTOLIC - diastolic is NEVER normal
- SWEET - not harsh sounding
- SOFT - grade II or less, thrill is NEVER normal
- SMALL - focal, limited to one area
- SINGLE - no other abnormalities
- SHORT - not holo/pansystolic
- SENSITIVE - may change with respiration or HR, not always present
What 3 important differences in auscultation are associated with heart disease in cats? What is required for definitive diagnosis?
- murmurs do NOT always correlate to cardiac disease
- systolic murmurs are common and can be pathologic or physiologic
- gallop + arrhythmia = likely cardiac disease
echocardiography
Respiratory vs. cardiac disease on PE:
What are some basic cardiac diagnostics?
- thoracic radiographs
- cardiac U/S
- arterial blood pressure
- ECG - rest, post-exercise, vagal maneuver, in-house continuous, Holter monitoring (event recorder used during specific times), ZIO (continuous 2-week period, take note of events)
- implantable loop recorder
- cardiac biomarkers - NT-proBNP, cardiac troponin I
What are some aspects to clinical pathology used for diagnosing cardiac disease?
- CBC/Chem/UA - not typically a lot of changes, baseline to determine if patient can be on heart medication
- thyroid function
- heartworm test
- blood cultures
- cardiac NT-proBNP
What is essential for diagnosing heart disease?
thoracic radiographs —> evaluates heart size, chamber sizes, lungs, pleural space, parenchyma, airways, pulmonary vasculature, edema
- minimum 2 views!
How is a vertebral heart score calculated on radiographs? What is considered normal?
- use calipers to measure the longest axis at the cardiac silhouette from the carina to the apex and short axis at the widest part perpendicular to the long axis
- transfer the long and short axes beginning at T4 and count how many vertebrae are contained in each
- sum the two measurements to get the VHS
NORMAL for dogs = 8.7-10.7
How is the vertebral left atrial size calculated? What is considered normal?
- use caliper to measure LA from ventral carina to the caudal border of the LA
- transfer the caliper to the cranial border of T4
- most commonly used is there is no access to ECHO
<2.3 vertebral bodies
VHS, cat:
Cardiomegaly, thoracic radiograph:
Enlarged LA, thoracic radiograph:
CHF vs. primary airway disease on thoracic radiographs:
Thoracic radiograph:
enlarged LA pressing on bronchus = coughing
What are the gold standards for diagnosing pulmonary edema and ascites to differentiate between left and right heart failure?
PULMONARY EDEMA = thoracic radiographs, LEFT
ASCITES = ultrasound, RIGHT
What is echocardiography used for? What can it NOT detect?
- direct imaging of chambers, vessels, and valves
- take measurements
- doppler - evaluate flow and pressure and valve anatomy
- B mode vs M mode
pulmonary edema - CHF
What are 8 key clinical uses for echocardiography?
- confirm or rule out presence of cardiac disease
- identify cardiomyopathies (HCM, DCM) and assess cardiac function
- identify congenital heart disease
- identify and measure pulmonary hypertension
- identify and assess pericardial effusion/disease and cardiac masses
- EPIC criteria for LV and LA enlargement to begin Pimobendan
- cardiac thrombi
- abnormal effusion
(NOT for CHF)
What is the ZIO patch?
small ambulatory cardiac monitor lacking lead wires with a single channel for ECG recording continuously up to 14 days
Why is NT-proBNP test used for monitoring heart disease?
increases with ventricular stretch or strain
- helps r/o cardiac disease in dogs and cats: negative rules in respiratory disease, positive can still be either
- can be continuously be monitored for progression of disease
Other than NT-proBNP, what cardiac marker is used to monitor cardiac disease? What does it monitor?
troponin I —> myocardial damage
Why are cardiac markers being used now to monitor cardiac disease as well?
helps with timely and accurate diagnosis and prognosticate primary cardiac diseases
- do NOT replace ECHO, but heps determine which patients need prompt cardiac workups
How do send-out and inhouse SNAP tests for NT-proBNP compare?
SEND-OUT = quantitative, designed to screen asymptomatic cases and is 95% accurate to RULE OUT clinical heart disease
IN-HOUSE = screens symptomatic animals when it is unsure if symptoms are from heart disease or not
How can cardiac catheterization be used?
DIAGNOSTIC - congenital abnormalities, evaluates pressures
THERAPEUTIC - presurgical/ballooning, pulmonic stenosis in Bulldogs
What diagnostics should be performed in with patients that collapsed, have left-sided CHF, ascites, arrhythmias, or pulmonary hypertension?
COLLAPSE - auscultation, echo, ECG
LS-CHF - thoracic radiography to assess for edema
ASCITES - ultrasound to differentiate right-sided CHF, cardiac tamponade, or systemic disease
ARRHYTHMIAS - ECG
PULMONARY HYPERTENSION - echo
What are 5 ways of diagnosing left heart failure in most small breed dogs?
- Is there a loud (3/6) murmur?
- Is there a lack of sinus arrhythmia?
- Is there dyspnea or panting in the exam room?
- Is there a really large heart or LA on radiographs?
- Does a Lasix trial help?
In what situations is cardiac disease (CHF) likely not the cause of signs in small breed dogs?
- not a huge murmur (>3)
- normal respiratory rate
- respiratory sinus arrhythmia
- normal heart on radiographs (especially LA)
How do large/giant breed dogs typically present with CHF?
- murmur not needed to be in CHF, especially with Doberman or Boxer cardiomyopathies
- can be difficult to hear if arrhythmia is present
