8. Examine the cardiovascular system of the horse and describe the findings Flashcards
Main steps in physical examination:
- Inspection
- Palpation
- Auscultation
- Percussion
Inspection:
Heart and vessels: check for trauma, deformity
Palpation:
Heart and vessels.
Check location and intensity of the heartbeat, heart rate, pain, trauma, deformity
Percussion:
Heart.
Detection of pain in the cardiac area
Secondary diagnostic methods of the heart:
- ECG
- Telemetric
- Echocardiograhpy
- Pericardiocentesis
- Lab tests
ECG:
resting ECG, base-apex lead most commonly used, Einthoven lead can also be used
Telemetric:
at rest -> picture or exercising ECG, special leads, during natural work, on treadmill
Echocardiography:
ultrasound examination with Doppler
Lab tests:
AST, CK, LDH, cardia troponin I
Location of heart:
2nd - 6th intercostal space
Where to locate heartbeat on each side:
LefT: 3rd-5th ICS
Right: 3rd-4th ICS
What is diastole?
heart muscle relaxes and allows the chambers to fill with blood
What is systole?
heart muscle contracts and pumps blood from the chambers into the arteries
What are the points for equine cardiac auscultation and where can they be heard?
- Mitral - left 5th ICS halfway between shoulder and sternum
- Aortic - left 4th ICS just below point of shoulder
- Pulmonic - left 3rd ICS just below point of shoulder
- Tricuspid - right 3rd - 4th
How many heart sounds are audible in horses?
All 4.
S1, S2, S3 and S4
What is S1 sound?
early ventricular contraction, AV closure, ejection w/semilunar opening. Beginnig of systole
What is the S2 sound?
closing of semilunar valves and back flow of blood.
End of systole
What is the S3 sound?
vibration of ventricular wall during passive filling of ventricle and is best heard over the apex.
Termination of rapid ventricular filling
What is the S4 sound?
The atrial sound and is detected in most horses.
Physiological murmurs;
occur in horses due to the size of the heart and volume of blood flow. They dont alter heart function
Grade: 1-3/6
Pathological murmurs:
- Systolic murmurs
- Diastolic murmurs
Systolic murmurs:
- caused by blood flow in aorta and pulmonary artery in early systole
- Left side of thorax
- Intensity may change with exercise
- PMI over aortic + pulmonary valves
Diastolic murmurs:
- Caused by ventricular filling
- Common in young horses and TB
- Left side of thorax
- PMI over mitral area
Grade 1/6
quiet murmur, heard only after careful auscultation
Grade 2/6
quiet murmur, heard immediately once the stethoscope is placed over its PMI
Grade 3/6
louder than grade 2, audible over a large area
grade 4/6
loud, very good audibility, without fremitus
Grade 5/6
louder than grade 4, with fremitus, audible with loose contact of the thoracic wall
Grade 6/6
loudest, audible when the stethoscope is held apart from the thoracic wall
