Cardiovascular Flashcards
Which are the general causes of peripheral edema?
- Increased hydrostatic pressure:
—- Increase plasma volume (CHF, renal disease, arteriovenous fistulas)
—- Venous obstruction - Decreased oncotic pressure
- Increased permeability
- Impaired lymphatic drainage:
—- Primary/congenital
—- Secondary: obstruction/destruction (inflammatory, infectious, neoplasia, surgery, trauma)
Which is the cause of myxedema?
Increase capillary leakage of proteins + reduction in lymphatic uptake
Which are the main causes of peripheral edema?
Vasculitis (40%) > venous/lymphatic obstruction (20%) > hypoalbuminemia (18%) > CHF-r (5%)
Localized (70%) (obstruction > vasculitis) > generalized (30%) (hypoalbuminemia)
CHFr is more typical to produce abdominal/pleural/pericardial effusion
Which is the mechanism of a vasovagal syncope?
Sudden autonomic nervous system failure, with a withdrawal of sympathetic tone and abrupt increase in vagal tone –> hypotension due to bradicardia + vasodilation
What is Bezold Jarisch reflex?
When a patient has a structural disease such as aortic stenosis or obstrive HCM, it exacerbates high left ventricular pressures –> stimulate ventricular pressure receptors (perceived as hypertension) –> vasovagal reflex
Which is the best biochemistry marker to distinguish between syncope and TCC seizure?
Phosphorus (P <0.97 100% E but 50% S of TCC seizure)
What variables determine the turbulence of blood?
- Blood velocity: + velocity, + turbulent
- Vessel diameter: + diameter, + turbulent
- Viscosity: - viscosity, + turbulent
Which are main causes of D-hyperlactatemia?
- Bacterial overgrowth
- EPI
- Diabetes mellitus
- Propylenglicol intoxication
Which factors affect/no affect to lactate concentration?
- No affect: venous/arterial sample
- Affect: exercise, food, stress, seixures, age
Which electrolytic disorder can be a marker of furosemide resistance and refractory tt?
Hypochloremia
How is the Laplace law?
Tension = P x (r/2h)
- Eccentric hypertrophy: secondary to volume overload
- Concentric hypertrophy: secondary to pressure overload
Which are the objectives of spironolactone administration in CHF?
- Diuretic effect (but low)
- Block of aldosterone detrimental effects on the vasculature (vasoconstriction) and cardiac remodeling
Which are the reasons torasemide have a decreased likelihood of patients to become refractory?
Diuretic effect + antialdosterone effect
Which are the most frequent areas of arterial thromboembolism?
- Iliac bifurcation
- Right subclavian artery
Which are the most common causes of arterial thrombus in dogs?
PLN (30%) > neoplasia > corticosteroids > endocrine > inf
In contrast to cats:
**Chronic course
**No cardiac cases!
**25% don’t reach a definitive diagnosis
Which are the effects of antiplaquetar agents in a thromboembolism?
- To prevent platelet aggregation and increasing the thrombus
- Inhibit production of thromboxane and serotonine, both of wich act reducing blood flow –> increase blood flow and collaterals.
Which is the most difference between unfractionated heparin and low molecular weight heparin?
LMWH have the same mechanism of action, but a reduced factor II inhibition –> whereas heparin can be monitored with PTT and TEG, LMWH have to be monitored with antiXa factor.
What is a NET?
Neutrophil extracellular traps: DNA, histones and proteins from activated neutrophils that are liberated to the extracellular –> componnet of innate immune response + prothroombotic.
Blood NETs TAE > no TAE –> can be a marker of TAE risk (specially citH3 more than cfDNA)
Which are the most common congenital diseases in dogs and cats?
- Dogs: PDA > SAS and AS > PS
- Cats: VSD > PDA > TVD > MVD > AV septal defect > AS
Which breed is predisposed to trichuspid dysplasia?
Labrador Retriever
Which breed is predisposed to mitral dysplasia?
Bull Terrier
Which are the most common clinical signs associated to degenerative valvular disease?
- Mitral valve disease: respiratory signs (dyspnea +/- cough). As a compensatory mechanism there is a eccentric hypertrophy of the ventricle and an increase in contractibility –> stroke volume no reduced –> no weakness/exercise intolerance. However, in cases where the stroke volume is reduced (because with time, contractibility is reduced), also weakness and exercise intolerance.
- Tricuspid valve disease: in general there is not important signs, but if it goes together with pulmonary hypertension, more signs.
How is the progression of radiographic changes?
A heart chamber enlargement has a slow phase of steadily progressing MMVD until about 6-12 months before the onset of CHF, when the rate of change of enalrgement is fast.
Which new markers of CHF exist in dogs?
- TMAO, L carnitine and choline: increased in CHF
- Heart Fatty Acid Binding Protein: increased in CHF
- Lymphos subtypes: increased CD8 and reduced CD4
- NLR and MLR: increased in CHF
- Galectin 3: increased in CHF
- Cystatin C (renal marker): increased in patients with less survival
Which antitussigens can be considered in a MMVD?
- Cough supressants:
—- Butorphanol
—- Hydrocodone
—- Dextrometorphane - To improve the low respiratory tract stability:
—- Bronchodilators
—- Steroids
—- Methylxantines (teophylline, aminopylline)
Which is the prevalence of concomitant LRTD and MMVD?
75%
Which is the etiopathogenesis of infective endocarditis?
Bacteremia and immunosupression/endothelial damage –> the toxics produced by the bacteria + inflammatory reaction leads to degeneration of the valve. Also production of immunecomplexes and thromboembolism.
Whics is the characteristic of Bartonella and Staph aureus infection in a endocarditis?
They are able to be internalized within endothelial cells and remain undiscovered by immune system.
Which are the most common clinical signs in endocarditis?
- Fever (50-90%) <– can present without fever (aortic involvement / Bartonella)
- Murmur (70%) <– 26% can present without murmur
- Lameness (35%)
- CHF (50%)
**gram negatives tends to course with acute/peracute disease, whereas gram positive have a more chronic course.
Which are the most common infectious agents cultured in endocarditis?
Staphylococcus, Streptococcus, E Coli, Pseudomonas, Corynebacterium, Erysepelotrix, Bartonella.
**study 2023 UK: Staph, Pasteurella, E Coli. No Bartonella.
Which are the Duke criteria?
- Major: culture positive (2 or more), new valculr insuficiency, compatible echocardio
- Minor: fever, >15kg, SAS, immunocomplexes disease, positive culture (less than 2), thromboembolic disease, high Bartonella serology
Which are the antibiotic of choice for endocarditis treatment?
Beta lactamic or imipenem + amikacina or enrofloxacine –> 6w
Which is the prognosis of endocarditis?
Poor (68% survival)
- Bad prognosis markers: gram negative or Bartonella infection, aortic involvement, thromboembolic disease,
- Favorable prognosis: gram positive infection, mitral involvement
Which are the most common analytical abnormalities found in a PPDH?
- Increased ALT (dog)
- Increased calcium (cat)
Which is the pathophiology of acute and chronic pericardial effusion?
- Acute: reduced diastolic volume right atrium –> reduced diastolic volume right ventricle –> reduced ejection volume right ventricle –> reduced venous return left atrium –> reduced ventricle filling –> hypotension
- Chronic: right CHF
Which is the pathophiosiology of pulsus paradoxicus?
In normal conditions, during inspiration there is a decrease in the intratoracic pressure –> blood flows preferentially into the low pressure vena cava, pulmonary veins, right atrium and right ventricle. It increases the right ventricular stroke volume during inspiration. In contrast, it reduces the preload of the left heart and the left ventricular stroke volume.
This process is more exxagerated in the presence of pericardial effusion (ventricular interdependence): expansion of the ventricles is limited by the presence of effusion, and any increase in the volume of one ventricle can only occur in expenses of the other –> a greater right ventricular filling during inspiration pushes the interventricular septum leftward, reducing the left ventricular chamber size and the left ventricular filling.
Which are the main infectious agents causing infective pericarditis?
Streptococcus, Pasteurella, Bacteroides, Coccidioides, Actinomyces
Which is the relevance of troponin in a pericardial effusion?
The concentration in dogs with pericardial effusion is greater than dogs with no effusion, and HSA is greater than other causes of pericardial effusion.