Colour flow Doppler echocardiography in horses with cardiac murmurs.

The research studies the use of color flow Doppler echocardiography in diagnosing cardiac murmurs in horses, specifically relating to tricuspid, mitral, and aortic regurgitation. It shows that the technique can identify larger regurgitant signals and longer regurgitant signals in horses with murmurs than those reported in healthy horses.

Research Methodology

• The study involved 32 horses that showed cardiac murmurs indicative of tricuspid, mitral, and aortic regurgitation.
• Color flow Doppler echocardiography was used to study these horses.
• Researchers measured the dimensions and duration of any regurgitant signals at the cardiac valve suspected as the murmur’s origin.
• Findings were then compared against flow signals recorded at valves in normal horses, based on previous research by Blissitt and Bonagura (1995).

Findings

• Horses with murmurs suggestive of tricuspid (8 horses) and aortic (8 horses) regurgitation showed larger regurgitant signals at the respective valves, compared to normal horses.
• Horses with murmurs suggestive of mitral regurgitation (8 horses) had a regurgitant signal of longer duration than that of normal horses, although the signal’s size was not larger.
• The comparison of two categories of horses with low and high-grade murmurs of tricuspid regurgitation demonstrated that horses with louder murmurs had longer and larger jets than those with low-grade murmurs.

Conclusions

• The research establishes that color flow Doppler echocardiography is an effective method for detecting valvular regurgitation in horses.
• However, quantification of jet size and duration remains important for differentiating physiological backflow, which occurs in normal horses, from valvular regurgitation associated with cardiac murmurs.

The study’s results contribute to our understanding of how to diagnose and evaluate heart conditions in horses more accurately. The ability to better distinguish between normal backflow and problematic regurgitation could lead to more effective treatment of equine heart conditions.