Cardiovascular Flashcards
(98 cards)
1
Q
2 components of the cardiovascular system
A
- Blood
- Heart & vessels
2
Q
Functions of the cardiovascular system
A
- Circulation
- Thermoregulation
- Fluid homeostasis
3
Q
3 layers of the heart wall
A
- Epicardium (visceral pericardium)
- Myocardium
- Endocardium
4
Q
Flow of electrical impulses through the heart
A
- SA
- AV
- HIS bundle
- Bundle branches
- Purkinje fibers
5
Q
Systemic compensatory mechanisms in response to injury
A
- Increased heart rate
- Increased peripheral vascular resistance
- Increased blood volume
- Redistribution of blood flow
6
Q
Cardiac compensatory mechanisms in response to injury
A
- Dilation
- Hypertrophy
7
Q
Increase in heart chamber volume
A
Dilation
8
Q
Increase in myocardial mass via increased cell size
A
Hypertrophy
9
Q
Gradual loss of pumping efficiency due to cardiac disease or increased workload
Results in decreased blood flow to tissues (ischemia) and pooling of blood behind failing chambers (congestion)
A
Congestive Heart Failure (CHF)
10
Q
Right-sided heart failure results in:
A
- Chronic hepatic congestion (“nutmeg liver”)
- Ascites
- Subcutaneous edema
11
Q
Left-sided heart failure results in:
A
Pulmonary congestion and edema
12
Q
Right/Left sided heart failure results in:
A
Hydrothorax
13
Q
Myocardial Diseases
A
- Hypertrophic cardiomyopathy (HCM)
- Thyrotoxic cardiomegaly
- Dilated cardiomyopathy (DCM)
- Arrhythmogenic right ventricular cardiomyopathy (ARVC)
- Restrictive cardiomyopathy (RCM)
- Feline left ventricular endocardial fibrosis (LVEF)
- Myocardial necrosis
- Nutritional myopathy
- Myocarditis
14
Q
Increase in size of cardiac myocytes, leading to increased overall mass
A
Myocardial hypertrophy
15
Q
True/False
Secondary myocardial hypertrophy is usually reversible
A
True
16
Q
True/False
Primary myocardial hypertrophy is usually irreversible
A
True
17
Q
Type of myocardial hypertrophy caused by pressure overload, resulting in increased wall thickness and decreased chamber volume
A
Concentric
sarcomeres added in parallel -> wider
18
Q
Type of myocardial hypertrophy caused by volume overload, resulting in increased chamber volume and normal or decreased wall thickness
A
Eccentric
sarcomeres added in series -> longer
19
Q
Disorder of myocardium
A
Cardiomyopathy
20
Q
3 main types of cardiomyopathy
A
- Hypertrophic
- Dilated
- Restrictive
21
Q
- Common in cats (esp. young to middle-aged males)
- Due to genetic mutation (MYBPC3) in Mainecoon and Ragdolls
- Gross Findings: cardiomegaly, concentric hypertrophy of LV (thickened wall & decreased volume), +/- LA dilation & thrombosis
A
Hypertrophic Cardiomyopathy (HCM)
DDx for HCM is thyrotoxic cardiomegaly due to hyperthyroidism in cats
22
Q
- Primary in some dogs breeds and cattle
- Secondary to nutritional imbalances in dogs & cats
- Gross Findings: cardiomegaly, eccentric hypertrophy of entire heart (dilated chambers & thin walls), enlarged rounded heart
A
Dilated Cardiomyopathy
ARVC is a variant of DCM found in Boxers
23
Q
- Primary heritable variant of DCM in Boxers
- Rare in cats
- Predisposition to ventricular arrythmias, syncope, heart failure, sudden death
- Gross Findings: RV myocytes replaced by adipose (or fibroadipose) tissue, RV normal or dilated, similar gross appearance to DCM
A
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)
“Boxer Dog Cardiomyopathy”
24
Q
- Rigid ventricular walls causing impaired ventricular filling
-
Includes multiple forms:
- LVEF
- Excessive moderator bands
- Congenital endocardial fibroelastosis in Burmese cats
- Endocardial fibrosis in aged rats
A
Restrictive Cardiomyopathy (RCM)
25
* Most common variant of RCM
* Endocardial fibrosis restricts ventricular filling
* Results from **endomyocarditis** (idiopathic inflammation)
* **Gross Findings:** thick opaque endocardium in LV
| *form of restrictive cardiomyopathy*
Feline Left Ventricular Endocardial Fibrosis (LVEF)
26
* Variant of RCM often found in cats
* Congenital defect that manifests later in life
* **Gross Findings:** bands of purkinje fibers and collagen in LV
| *form of restrictive cardiomyopathy*
Excessive Moderator Bands
27
Cardiomyopathy sequale
* **Arrhythmia** -> syncope, sudden death
* **Thrombosis** -> thromboembolism -> ischemia, infarcts
* **Congestive heart failure** -> death
28
# True/False
Cardiac myocytes are able to regenerate
False
29
# True/False
Small areas of myocardial necrosis generally do not cause any problems
False
30
# True/False
Necrotic myocardiocytes are **hypereosinophilic** & **fragmented**
True
31
Is this acute or chronic myocardial necrosis?
Acute
| myocardial pallor, dry +/- gritty texture, dystrophic mineralization
32
Is this acute or chronic myocardial necrosis?
Chronic
| firm, depressed (sunken) myocardial scar (fibrosis)
33
Causes of myocardial necrosis
* Nutritional
* Toxic
* Ischemic
* Genetic
* Traumatic
34
# True/False
Heart attacks are common in animals
False
| uncommon in animals due to low incidence of coronary artery disease
35
Examples of myocardial toxins
* Ionophores
* Cantharidin
* Gossypol (cottonseed oil)
* Doxorubicin
* Poisonous plants
36
# True/False
Vitamin E / selenium decifiency is a cause of nutritional myopathy
True
| *"White Muscle Disease in ruminants, Mulberry Heart Disease in swine*
37
Vitamin E / selenium deficiency sequale
decreased antioxidant activity -> oxidative membrane damage -> myocyte necrosis
38
Inflammation of the myocardium
Myocarditis
39
Causes of myocarditis
Often infectious:
* **Viral** (CPV-2, encephalomyocarditis virus, FMDV, WNV)
* **Bacterial** (*Clostridium chauvoei, C. piliforme, Corynebacterium pseudotuberculosis, Histophilus somni*)
* **Fungal** (*Aspergillus*)
* **Parasitic** (*Toxoplasma gondii, Sarcocystis, Neospora, Trypanosoma cruzi, Theileria parva*, cysticercosis)
40
Granulomatous myocarditis in a dog
| from *Aspergillus terreus* infection
41
Suppurative myocarditis in a cow
| from *Histophilus somni* infection
42
* Idiopathic degeneration of valvular collagen
* Common in small, aged dogs (e.g. Cavalier King Charles)
* Mitral valve most commononly affected
* **Gross Findings:** thickened nodular valve margins, smooth, glistening, opaque
* **Microscopic Findings:** loose fibroblastic tissue, NON-INFLAMMATORY
Endocardiosis
| "Myxomatous Valvular Degeneration"
43
Endocardiosis sequale
* **Valvular insufficiency** -> regurgitation, heart murmur
* **Atrial volume overload** -> eccentric hypertrophy +/- CHF
* **Atrial subendocardial fibrosis** -> jet lesion
* **Atrial thrombosis** -> thromboembolism +/- infarcts
* **Chordae tendinae rupture**
* **Atrial rupture** -> hemopericardium
44
The arrow is an example of:
Atrial Jet Lesion
| commonly seen in endocardiosis
45
The arrows are examples of (2 lesions):
Atrial Thrombosis & Chorda Tendinea Rupture
| commonly seen in endocardiosis
46
Inflammation of endocardium
Endocarditis
47
* Inflammation of endocardium
* Usually bacterial
* Tricuspid valve lesions most common in cattle
* Mitral valve lesions most common in other species
* **Gross Findings:** thrombi vegetations on valvular endocardium
* **Microscopic Findings:** fibrin, bacteria, neutrophils
Endocarditis
| "Vegetative Valvular Endocarditis"
48
# True/False
Vegetative endocarditis is caused by **idiopathic inflammation following a stressful event**, leading to thrombosis
False
| caused by chronic sustained bacteremia & endocardial damage
49
Endocarditis sequale
* **Valvular insufficiency** -> CHF
* **Bacteremia** -> septic thromboemboli to heart, kidney, brain
* **Infarcts**
* **Inflammation**
50
Endocardial Mineralization
51
Causes of endocardial mineralization
* **Vitamin D Toxicosis** (oversupplementation, cholecalciferol rodenticides, calcinogenic plants)
* **Johne's Disease** (*Mycobacterium avium* ssp. *paratuberculosis*)
* **Uremia** in dogs
52
# True/False
There are two continuous serous layers that enclose the pericardial cavity:
1. **Visceral layer** = epicardium, adherent to heart
2. **Parietal layer** = pericardial sac, associated with fibrous outer portion
True
53
* Fluid accumulation in pericardial cavity
* Named according to fluid composition
* Clinical significance depends on whether fluid accumulates slowly or rapidly
Pericardial Effusion
| Hydropericardium, Hemopericardium, Pericarditis (inflammatory exudate)
54
Heart compression due to rapid increase in pressure in pericardial cavity. Can lead to **cardiogenic shock** & death.
Cardiac Tamponade
55
Routes of pathogen entry during pericarditis
* Hematogenous (e.g. septicemia)
* Direct Penetration (e.g. hardware disease)
* Local Extension (from myocardium, pleural cavity, mediastinum)
56
Is this acute or chronic pericarditis?
Acute
57
Is this acute or chronic pericarditis?
Chronic
58
This is the heart of a severely emaciated dog, why does it have a translucent gelatinous appearance?
Serous Atrophy of Pericardial Fat
59
# True/False
Serous atrophy of pericardial fat is a common finding in obese animals
False
| indicator of emaciation
60
# True/False
In the normal postnatal heart, the right side of the heart is **HIGH** pressure & the left side of the heart in **LOW** pressure
False
| right (pulmonary) = LOW pressure
left (systemic) = HIGH pressure
61
Examples of systemic to pulmonary shunts (LEFT to RIGHT)
* Patent Ductus Arteriosis (PDA)
* Foramen Ovale failure to close
* Ventricular Septal Defect (VSD)
| *may have reversal of flow (RIGHT to LEFT) later in disease*
62
What congenital anomaly does this depict?
Patent Ductus Arteriosus (PDA)
63
What congenital anomaly does this depict?
Ventricular Septal Defect (VSD)
64
Pulmonic Stenosis (PS) leads to:
**Pressure overload** in right ventricle, **concentric RV hypertrophy**
65
Subaortic Stenosis (SAS) leads to:
**Pressure overload** in left ventricle, **concentric LV hypertrophy**
66
Mitral or Tricuspid Valve Dysplasia leads to:
Valvular insufficiency (regurgitation), **volume overload** in atria, **eccentric atrial hypertrophy**
| *stenosis less common*
67
Raised fibrous ring below aortic valve, concentric LV hypertrophy
Subaortic Stenosis (SAS)
68
Malformed mitral valve leaflets, eccentric LA hypertrophy
Mitral Valve Dysplasia
69
Examples of malpositioned great vessels
* Persistent right aortic arch (PRAA)
* Transposition of aorta & pulmonary artery
* Persistent truncus arteriosus
* Double outflow right ventricle
70
Single blood vessel from RV & LV
Persistent Truncus Arteriosus
71
Aorta arises from RV instead of LV
Double Outflow Right Ventricle
72
* Vascular ring anomaly that entraps esophagus and trachea
* Aortic arch on right, ligamentum arteriosum on left
* Can result in megaesophagus, regurgitation, aspiration pneumonia
Persistent Right Aortic Arch (PRAA)
73
Congenital anomaly where the heart develops outside of the thoracic cavity
Ectopia Cordis
74
Translocation of peritoneal viscera into pericardial sac
Peritoneal-Perircardial Diaphragmatic Hernia
75
Congenital anomaly consisting of four concurrent lesions, resulting in **RIGHT to LEFT** shunt and **cyanosis**
* pulmonis stenosis
* RV hypertrophy (secondary to PS)
* ventricular septal defect
* aortic dextroposition
Tetralogy of Fallot
76
Common incidental cardiac anomaly of ruminants
Valvular Hemocysts / Lymphocysts
77
Inflammation of arteries
Arteritis
78
Inflammation of many arteries
Polyarteritis
79
Inflammation of veins
Phlebitis
80
Inflammation of lymphatic vessels
Lymphangitis
81
*
* Gross Findings: thickened vessels
* Microscopic Findings: leukocytes +/- fibrin around vessel walls
Vasculitis
82
Infectious causes of vasculitis
* **Viral** (equine viral arteritis, African horse sickness, malignant catarrhal fever, bluetongue, classic swine fever, African swine fever, FIP)
* **Bacterial** (*Salmonella, Erysipelothrix rhusiopathiae, Haemophilus, Histophilus somni, Rickettsia rickettsia, Borrelia burgdorferi*)
* **Fungal** (*Aspergillus*)
* **Parasitic** (*Strongylus vulgaris, Dirofilaria immitis, Angiostrongylus vasorum*)
83
Immune-mediated/idiopathic causes of vasculitis
* Polyarteritis nodosa
* Idiopathic necrotizing polyarteritis ("Beagle Pain Syndrome")
84
Hardening of arteries
Arteriosclerosis
| rarely of clinical significance in animals
85
* Subset of arteriosclerosis
* **Hardening of arteries accompanied by plaques of fatty material**
* Narrowing or arterial lumen -> ischemia, infarct
* Occurs in pigs, rabbits, chickens fed **high cholesterol diet**
* Associated with **hypothyroidism** & **diabetes mellitus** in dogs
Atherosclerosis
86
# True/False
Heart attacks are common in animals
False
87
* **Localized vascular dilation** due to thinning or weakening of vessel wall, can lead to **fatal rupture**
* Causes include: copper deficiency, *Strongylus vulgaris* migration, idiopathic
Aneurysm
88
* Benign neoplasm of vascular endothelial cells
* Sharply demarcated
* Blood-filled spaces lined by well-differentiated endothelial cells
* Common in dogs
Hemangioma
89
* Malignant neoplasm of vascular endothelial cells
* Commonly found on right atrium, liver, spleen, skin, fat around urinary bladder
* Blood-filled spaces lined by pleomorphic endothelial cells
* Rupture can lead to hemopericardium, hemothorax, hemoabdomen
Hemangiosarcoma
90
Infiltrative endothelial neoplasm affecting ventral abdominal dermis/subcutis in cats, bruised edematous tissue
Feline Ventral Abdominal Lymphangiosarcoma
91
Neoplasm originating from aortic body (a chemoreceptor) at base of heart, common in brachycephalic dogs
| -may compress great vessels
Chemodectoma
92
Bulging tan masses in heart, associated with bovine leukemia virus (BLV) in cattle
* Common sites: right atrium, abomasum, uterus, spinal canal, retrobulbar region, kidney, lymph nodes
Cardiac Lymphosarcoma (LSA)
93
Which cell adaptation is primarily responsible for increased myocardial mass in an adult animal?
Hypertrophy
94
Concentric hypertrophy occurs when sarcomeres are added in parallel due to what?
Pressure Overload
95
Eccentric hypertrophy occurs when sarcomeres are added in series due to what?
Volume Overload
96
An **inflammatory** condition of the endocardium and usually develops secondary to bacteremia and endocardial injury.
Endocarditis
97
A **non-inflammatory** condition of the endocardium (usually seen in dogs) characterized by idiopathic degeneration of the valvular collagen.
Endocardiosis
98
This two-word term refers to a life-threatening condition in which the heart is compressed and prevented from adequately filling due to accumulation of fluid in the pericardial cavity:
Cardiac Tamponade
