acquired valvular disease in LA Flashcards
(30 cards)
what does a diastolic murmur usually mean and characteristics
- aortic regurgitation
- grade 1-6/6, decresdcendo, often musical
- > 10 yrs, usually older
- bounding peripheral pulse (not grade)
when does AR need further evaluation (echo)
- when aterial pulses bounding
- when horse is young
- when horse has other signs of heart dx (excersize intolerance, HR, RR effort, ventricular arrhythmias, mitral regurgitation murmur, VSD murmur, atrial fibrilation)
- when horse has unknown fever
- prepurchase exam
- athlete
what does AR need if its moderate or severe
excercising ECG
what is arrhythmogenesis in AR & exercise
- ventricular enlargemenet & remodeling
- decreased coronary perfusion
- shortened diastole cause by high HR
- increased oxygen demand
- increased sympathetic tone caused by the exercise
what is the clinical relevance of AR
- clinically irrelevant
- excercise intolerance
- safety concerns
- heart failure
- endocarditis
- echo
- exercise ECG
what is pulmonic valve dx
- often clinically insignificant
- except: endocarditis and severe pulmonic stenosis
what is mitral regurgitation
- a loud L sided systolic murmur is MR until proven otherwise
- grade 1-6/6 - no correlation with severity
- often incidental but also most common cause of CHF
what are the signs of MR
- exercise intolerance
- increase HR
- increase RR and effort
- cough
- edema
- arrhythmias (AF)
what is the predisposing factor to AF in MR and equine CHF
atrial enlargement
development of AF can tilt into CHF in severe MR due to:
loss of atrial contraction
when does AF in MR and quine CHF occur
increased rate = needs rate contool
why is cardioversion contraindicated
due to tx complications while in CHF & almost certain recurrence
ruptured chord is a marker of ____
severity
when do horses with a L sided murmur need an echo
all cases unless physiologic murmur or retired horse in which owner understands all monitoring
what is tricuspid regurgitation (TR)
- most common cause of R sided systolic murmur
- frequent in standardbred
- grade and severity correlated
- rarely causes performance problems or heart failure
what are exceptions to TR
- very severe TR or atrial enlargement that predisposes to atrial fibrillation
- endocarditis
- secondary to MR and PH
what are the most common causes of jugular pulses in horses
ventricular tachycardia and TR
TR needs further evaluation (echo) if…
- 4-6/6 holo or pansystolic
- other signs of heart dx (exercise intolerance, HR, atrial fibrilation, jugular pulses)
- FUO or thrombophlebitis
- secondary to MR and PH
what is the clinical relevance of TR
- clinically irrelevant most of the time
- rarely causes performance problems, safety concerns or HF
- echo
what is severe TR in horses with CHF
- often secondary to L side disease (MR & AR)
- right sided CHF
- venous distention, jugular pulsations, ventral edema
- pleural effusion, hepatic congestion, ascites (rare)
- AF and tachycardia (>60/min) often present
continuous murmurs
what is aortocardiac fistula
- connection from aortic root-RV, RA or LV
- signs may be distress, arrhymia or colic
- associated with ventricular arrhythmias
- unsafe to ride/risk of sudden death
- life expectancy days-months
continuous murmurs
what is patent ductus arteriosus (PDA)
- murmur may be present physiologically < 72-96 hrs
- very rare in “non-neonate”
treatment of CHF
- diuretics: furosemide - torsemide
- ACEI: benazepril
- rate control: digoxin mainly in AF
- pimobendan: little info and expensive
- inotropes (dubutamine), sedation for dyspnea, oxygen, sildenafil, brochodilators, spironolactone, nitroglycerine
what to watch for with horses with CHF
tolerance to exercise, HR, RR and effort
