Cardiopulmonary Diseases

cardiomyopathies

diseases of the heart muscle

dilated cardiomyopathy

what is canine DCM?

old, male, large & giant breeds

in what age, sex, and size dogs is DCM more prevalent in?

• Dobermans

• Irish Wolfhounds

• St. Bernards

• Newfoundlands

• Afghans

• Cocker Spaniels**

what are the breed predilections for canine DCM?

• exercise intolerance

• weakness

• coughing

• weight loss

• anorexia

• cool extremities

• abdominal distention

clinical signs of DCM

• radiographs

  • cardiomegaly

  • pleural effusion

  • ascites

• echocardiogram**

  • thin muscle mass of ventricles +/- atria

  • valvular regurgitation

• electrocardiogram (ECG)

  • arrhythmias

• bloodwork

  • Pro-BNP

  • cardiac troponin

diagnosis for DCM

1. protein released with stressed cardiac muscle

2. moderate sensitivity & specificity, so best used in conjunction with other diagnostics

1. what is Pro-BNP?

2. how sensitive is it diagnostically?

1. protein released with cardiac muscle damage

2. indicates more the extent of damage rather than diagnosing dz

1. what is cardiac troponin?

2. what does it indicate?

treatment

• oral medications

  • positive inotropes (pimobendan, digitalis)

  • vasodilators / ace inhibitors (enalapril / benazepril)

• supplements (more beneficial in Cocker Spaniels)

  • taurine

  • L-carnitine

• treat for heart failure if presents

• NO CURE - goal is to keep the pt comfortable

treatment of DCM

~50% survival 1 yr post diagnosis

prognosis of DCM

1. increases contractility & dilates blood vessels

2. reduces resistance to cardiac output

3. decrease fluid retention by dilating blood vessels

1. what do positive inotropes do?

2. what do vasodilators do?

3. what do ace inhibitors do?

1. heritable biochemical

2. dilation

canine DCM

• suspected to be (1)_________ _________ underlying problem

• diet associated? - think grain-free diets

• results in (2)_______ of the left & right ventricles with some atrial _______ as well

1. dilation; decreased

2. decreased

3. increased

4. regurgitation; murmur

5. congestive heart failure

(1) DCM = _________ of the cardiac muscles results in weak, thin, flabby heart walls & ____________ contractility

• (2)__________ cardiac output

• (3)__________ cardiac afterload

• mitral & tricuspid (4)__________ is possible (resulting in heart _______)

• (5) congestion of blood in the veins due to poor cardiac output may result in…

cardiac output

amount of blood circulated out of the heart per minute

stroke volume

amount of blood circulated out of the heart per beat

cardiac afterload

amount of blood remaining in the heart after contraction

1. taurine

2. 1990s; taurine

3. rare

4. taurine supplementation

feline DCM

• associated primarily with (1)_______ deficiency in the diet

• common prior to the (2)_____ when commercial diets were changed to incorporate more _______

• (3)_____ today, but may be observed in patients on home-made diets that are not properly balanced

• (4) treatment…

• **otherwise similar to canines

1. thickening; left; decreased; left

2. left; dilation

3. malpositioning; regurgitation

feline hypertrophic cardiomyopathy (HCM)

• (1)_________ of the ____ ventricular myocardium, resulting in ___________ volume in the ____ ventricle

• results in back-up of blood in the (2)____ atrium & secondary atrial _________

• may result in (3)______________ of the mitral valve leaflets & secondary mitral ______________

thromboemboli

______________ may form in the atrium & break off to move to the aorta, causing a saddle thrombus

saddle thrombus

when a blood clot from the heart lodges at the bifurcation of the aorta & blocks the femoral artery

• often asymptomatic until secondary heart failure occurs

• depression

• anorexia

• crying

• rear leg paralysis

• dyspnea

clinical signs of feline HCM

Maine Coon, Ragdoll

breed predispositions for feline HCM

• radiographs

  • “valentine” shaped heart w/ pronounced atria

  • pleural effusion

  • hepatomegaly

• echocardiogram***

  • thickened ventricular walls / septum

  • dilated left atrium

  • +/- mitral regurgitation

• bloodwork

  • Pro-BNP is slightly more sensitive in cats

  • cardiac troponin

diagnosis of feline HCM

• controversial in asymptomatic cats

  • new drug studied - rapamycin

• diltiazem (calcium channel blocker) - may allow some regression of moderate hypertrophy by inhibiting cardiac contractility

• tx for heart failure if present

• clopidogrel (plavix) - to reduce risk of clot formation

treatment of feline HCM

• varies with progression of disease in asymptomatic cats

• poor prognosis if congestive heart failure present

prognosis of feline HCM

1. rare

2. small

3. echocardiogram

canine hypertrophic cardiomyopathy

• (1)____ in dogs

• typically (2)______ breeds

• diagnosis via (3)_____________

• tx the same as cats

congestive heart failure

end stage process from other underlying heart diseases (DCM, HCM, etc.)

• exercise intolerance

• coughing

• dyspnea

• abdominal distention

• sudden death

clinical signs of congestive heart failure

congestion; edema

CHF = heart pump failure leading to ___________ of blood within the vena cava & _______ in the body (pleural effusion, peritoneal effusion)

• radiographs

• echocardiogram

diagnosis of CHF

true!!

true or false: do NOT stress dyspneic patients for radiographs

• oxygen therapy for distressed patients

• oral medications

  • diuretics (furosemide / lasix)

  • +/- beta-blockers (atenolol)

  • anti-thrombolics (aspirin, clopidogrel / plavix)

  • ace inhibitors (enalapril)

  • +/- pimobendan (vetmedin)

• thoracocentesis

• abdominocentesis

treatment for CHF

true

true or false: ace inhibitors are a specific type of vasodilator

poor

prognosis of CHF

false!! - they are often heritable genetic traits

true or false: it is okay to breed animals with congenital defects

1. aorta; pulmonary artery

2. 14 hours

3. 4-6 days

4. volume; left

patent ductus arteriosus (PDA)

• shunting of blood from the (1)______ to the __________ ______

• normal shortly after birth, but should functionally close within (2)__ hours after birth in dogs & cats

  • does occur in foals & calves - should close normally within (3)__-__ days

• results in (4)________ overload of the ____ side of the heart

• often none

• exercise intolerance

• failure to thrive

• coughing

clinical signs of PDA

• continuous murmur on PE

• ECG

• radiographs

• echocardiogram**

diagnosis of PDA

• surgical tie off of shunt

• canine ductal occluder

treatment for PDA

• good w/ treatment

• without treatment

  • poor

  • ~60% will die within 1 year

prognosis of PDA

1. ventricle septum; left; right

2. aortic

3. left

4. right

ventricular septal defect (VSD)

• failure of the (1)___________ ______ to completely close during fetal development so blood is shunted from the _____ ventricle to the _____ ventricle

  • opening usually remains just below the (2)_____ valve

• smaller VSDs will overload the (3)_____ side of the heart

• larger VSDs may have more (4)_____ sided effects

• often none

• exercise intolerance

• failure to thrive

• coughing

clinical signs of VSD

• systolic murmur on PE

• radiographs

• echocardiogram***

diagnosis of VSD

• some tertiary hospitals may be able to do open-heart repair

• most patients are only able to be medically managed for congestive heart failure if present

treatment of VSD

• small defect: good

• large defect: guarded

prognosis of VSD

1. atrial septum; left; right

2. right

atrial septal defect (ASD)

• defect in the (1)_______ _______, resulting in shunting of blood from the _____ atrium to the _____ atrium

• leads to volume overload of the (2)_____ side of the heart

usually none

clinical signs of ASD

• +/- heart murmur on PE

• radiographs***

• echocardiogram

diagnosis of ASD

• medically manage heart failure if present

• open heart surgery

• canine ductal occluder

treatment of ASD

varies with size of defect

prognosis of ASD

1. narrowing; ventricle

2. ventricular hypertrophy

valvular stenosis (pulmonic or aortic)

• (1)__________ of the pulmonary or aortic valve, resulting in pressure build up in the __________ on the same side

  • increased pressure results in (2)__________ __________

• asymptomatic

• exercise intolerance

• syncope

• sudden death

clinical signs of valvular stenosis

• murmur on PE

• radiographs

• ECG

• echocardiogram***

diagnosis of valvular stenosis

• balloon dilation

• surgical correction

treatment of valvular stenosis

• good with mild stenosis

• severe stenosis usually results in 1-3 yr lifespan

prognosis of valvular stenosis

1. ventricular septal defect

2. pulmonic stenosis

3. right ventricular hypertrophy

4. overriding aorta

what are the 4 defects seen with tetralogy of fallot?

aorta is located over the ventricular septal defect rather than the left ventricle; oxygen deficient blood is distributed around the body

what is an overriding aorta?

1. pulmonary artery; stenosis

2. hypoxemia

3. cyanosis

4. polycythemia

tetralogy of fallot

• blood shunting through the VSD rather than into the (1)_________ ______ (in part due to pulmonic ______) results in…

  • (2)_______ = low oxygen concentration in the blood

  • (3)_______ = blue discoloration to the skin / tissues

  • (4)_______= increase in red blood cells

• syncope

• failure to thrive

• hyperpnea

• cyanosis

• exercise intolerance

clinical signs of tetralogy of fallot

increased depth & rate of breaths

what is hyperpnea?

• murmur on PE

• ECG

• radiographs

• echocardiogram***

diagnosis of tetralogy of fallot

• phlebotomy

  • treats for the polycythemia, but not the hypoxemia

• surgery rarely performed

treatment of tetralogy fallot

average lifespan is 3-4 years

prognosis for tetralogy fallot

persistent right aortic arch (PRAA)

most common vascular ring anomaly

1. regress

2. esophagus; obstruction

persistent right aortic arch (PRAA)

• fetuses have multiple pairs of aortic arches during development that will usually (1)_______ throughout later stages of development

• if the right aortic arch remains, it entraps the (2)_________ & can result in _________

• regurgitation

• poor growth

• coughing & fever (from aspiration pneumonia)

clinical signs of PRAA

radiographs with barium contrast

diagnosis of PRAA

ligation of the persistent vascular ring

treatment of PRAA

1. degenerative; shortening / thickening

2. chordae tendinae

3. regurgitate; ventricular contraction

pathogenesis of endocardiosis

• (1)___________ change in the valves, resulting in ___________ / ___________ of the valve leaflets

  • also possible rupture of the (2)___________ ___________

• structural change results in the inability of the valves to close completely so blood is able to (3)___________ back into the atrium with ___________ ___________

valve disease, valve regurgitation, valve insufficiency

endocardiosis, aka…

the mitral valve

which valve is most commonly effected with endocardiosis?

endocardiosis

what is the most common cardiac disorder in dogs?

1. Cavalier King Charles Spaniels & Dachshunds

2. males

3. 10 yrs

endocardiosis

• (1) what are the breed predispositions?

• more common in (2)_______ (males or females?)

• usually develops after (3)__ years of age

• coughing

• dyspnea

• decreased appetite

clinical sings of endocardiosis

• systolic murmur on PE

• echocardiogram***

• elevated pro-BNP

diagnosis of endocardiosis

• goal = give the pt a good QOL; no cure or preventative measures

• weight management

• treat for congestive heart failure if it presents

treatment of endocardiosis

varies with extent of progression of disease

prognosis of endocardiosis

1. valves

2. mitral

3. aortic

4. tricuspid

bacterial endocarditis

• bacteria in the bloodstream accumulate on the (1)______ of the heart

• primarily the (2)______ valve is influenced in cats & dogs

  • (3)______ valve in horses

  • (4)______ valve in cattle

1. ulceration

2. collagen; platelets

3. fibrous vegetations; antibiotics

4. deform

pathogenesis of bacterial endocarditis

• infection results in (1)_________ of the valve leaflets

• exposes (2)________, which attracts ________ to the area

• (3)_______ __________ form over the platelets, which prevents __________ from getting to the bacteria

• vegetations (4)_______ the valve leaflets

• weight loss

• lethargy

• depression

• inappetance

• fever

clinical sings of bacterial endocarditis

• sudden onset heart murmur

• endocardiogram - masses on thickened valve leaflets

• blood cultures

diagnosis of bacterial endocarditis

• treatment = aggressive antibiotic therapy

• prognosis = guarded

treatment & prognosis of bacterial endocarditis

• progression of renal disease

• retinal detachment

• stroke

• left ventricular hypertrophy

what secondary tissue damage can hypertension cause?

elevated; 160

hypertension = ________ blood pressure; systolic BP >___mmHg

1. in-clinic

2. normotensive

3. autonomic

4. true

situational hypertension

• increased blood pressure resulting from (1)__-_____ measuring

  • pt is (2)__________ at home

• (3)_________ nervous system response (fear / excitement)

• (4) true or false: routine BP screening is not rec’d in otherwise healthy patients due to this condition

• renal disease

• Cushing’s disease

• diabetes

• pheochromocytoma

what are some common diseases causing secondary hypertension?

secondary hypertension

pathological elevation in blood pressure resulting from another disease process

as a side effect of certain drug administration

other than from another disease process, how else can secondary hypertension occur?

normal CBC / chem / UA w/ elevated BP measurement in relaxed pt

diagnosis of idiopathy hypertension

idiopathic hypertension

elevation in blood pressure thought to be due to a combination of genetic, lifestyle, and environmental factors

direct blood pressure vs. indirect blood pressure reading

diagnosis of hypertension

• antihypertensive drugs

  • ace inhibitors (enalapril, benazepril)

  • calcium channel blockers (amlodipine)

treatment of hypertension

true

true or false: routine monitoring of BP in patients with hypertension is recommended as it may be progressive

cardiac arrhythmias

variation from the normal cardiac rhythm

• sinoatrial (SA) node

• atrioventricular (AV) node

• bundle of His

• ventricles

the rhythm of the heart is maintained by electrical impulses fired by the pacemakers…

arrhythmias

_________ may occur if there is an abnormal pacemaker or a conduction disturbance

• area of damage that prevents the heart from “recharging” appropriately

• cardiac disease

  • hereditary

  • acquired

    • cardiomyopathies

    • endocarditis

    • neoplasia

• autonomic nervous responses

  • vagal stimulation

  • excitement

  • fear

  • pain

• hypoxia

• acid-base disturbances

• electrolyte abnormalities

• systemic disease

what are some causes of abnormal arrhythmias?

• P wave = atrial depolarization

• QRS complex = ventricular depolarization

• T wave = ventricular repolarization

what do the P wave, QRS complex, and T wave represent on an ECG

SA; R-R

a normal sinus rhythm is electrical activity that initiates from the __ node & features consistent __-__ intervals

respiratory sinus arrhythmia (RSA)

heart rate increases with inspiration & decreased with exhalation (R-R intervals are not consistent)