Echocardiography in the horse.

This research used echocardiograms to gather data on heart dimensions in healthy horses, measuring attributes such as left ventricular wall thickness, chamber diameter during different heart phases, aortic root dimensions, and factors related to heart function.

Echocardiographic Methodology

• The study utilized echocardiography on standing, clinically normal horses. Echocardiography is a test that uses sound waves to produce live images of the heart, allowing the researcher to see how it’s beating and pumping blood. This non-invasive technique is highly useful in assessing cardiac health.
• They used an ultrasonic recording device and the echobeam, the ultrasound beam, was directed towards the right thoracic wall of the horse, specifically within the area of the 4th to 5th intercostal space. Here, a study frequency of 2.5 mHz was used. The intercostal space is the space between two ribs, and this area was chosen for its proximity to the horse’s heart.

Dimensions and Cardiac Indicators

• The researchers calculated the left ventricular wall thickness obtaining a mean value of 3.2cm, which gives insights into the heart’s muscle mass and its potential for pumping blood.
• The left ventricular chamber diameter in diastole and systole, the phases of the heart’s cycle when it’s relaxing and contracting respectively, were measured. The findings showed it to be 9.3 cm in diastole and 5.7 cm in systole, highlighting the noticeable change in size as the heart beats.
• The dimensions of the aortic root – the component of the aorta closest to and directly connected with the left ventricle of the heart – were acquired, with a mean result of 7.7 cm. This is an essential metric in cardiovascular research, as the aortic root plays a vital role in the correct functioning of the aortic valve and the outflow of blood from the heart towards the rest of the body.
• Lastly, they calculated two more heart functioning indicators. The mitral valve closing slope (E-F), was calculated to be 17.7 mm/second. This gives details about the functioning of the mitral valve, which controls blood flow between the two left chambers of the heart. The percentage of delta D, a correlate of the ejection fraction, was 38.6 %. The ejection fraction is a measurement of the percentage of blood leaving your heart each time it contracts, which offers insights into the heart’s pumping efficiency.