Haemodynamics in the horse: 1. Pressure pulse contours.

This research involves the examination of pressure pulse contours in horses’ hearts using a catheter with two transducers. It also observes how these waveforms adjust under different conditions, such as AV block, ectopic beats and pulmonary disease.

Overview of the Research

• The research was conducted on eight horses, wherein their cardiac conditions were thoroughly examined using a catheter with two transducers, one at the tip and the other 9 cm proximal to it.
• This instrumental setup allowed the researchers to record transvalval pressure waveforms, which essentially are graphical representations of the pressure changes occurring in the heart and the great vessels in real-time.
• Alongside the pressure waveforms, an electrocardiogram was simultaneously recorded to provide a standardized time base. This ensured synchronicity between the time-based events of the cardiac cycle and the gathered pressure data.

Analysis of Cardiac Events

• The study describes the variations in these waveforms as they occur in different chambers of the horse’s heart and the great vessels. It shows the correlation between these waveforms and the events of the cardiac cycle, essentially linking the pressure changes to the operational reality of the heart.
• This kind of analysis provides a unique and valuable insight into the pathological and physiological behaviors of horses’ cardiac systems. For instance, the waveforms observations can detail how effectively the heart is pumping or whether any abnormalities, like arrhythmia, are present.

Examination of Cardiac Conditions

• The research further explores the effects of certain conditions on the horse’s heart. They include second degree AV (Atrioventricular) block, ectopic beats, a pan diastolic murmur, and chronic obstructive pulmonary disease.
• A second-degree AV block refers to a partial blockage in the heart’s electrical conduction system between the atria and the ventricles. Ectopic beats refer to irregular heartbeats originating outside the heart’s normal rhythm-making place. A pan diastolic murmur refers to a kind of heart murmur that persists throughout the diastolic phase of the heart’s cycle. Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease usually found in older horses.
• This exploration helps in understanding how these conditions affect the mechanical activity of the heart as observed from pressure pulse contour perspective, thereby helping in devising targeted treatments and therapies for these conditions.