Normal Arterial pulse physiology waveform, pulse tracing, applied | CVS physiology mbbs | practical

Summary

This video delves into the physiology of arterial pulse and its variations, exploring how pressure waves in the arteries, caused by ventricular contraction, create different pulse waveforms. The script explains normal pulse characteristics and abnormalities such as pulsus parvas, pulsus tardus, water hammer pulse, and bisferiens pulse. The causes and physiological changes that lead to these variations, such as stroke volume, vascular compliance, and peripheral resistance, are also covered. Additionally, the video highlights diagnostic methods, including how to assess abnormal pulses, helping viewers better understand the clinical implications of pulse waveforms in various cardiovascular conditions.

Takeaways

• 😀 The arterial pulse is a pressure wave created by the contraction of the left ventricle, not due to blood flow itself.
• 😀 The velocity of the arterial pulse wave varies across different arteries: approximately 4 m/s in central arteries and 16 m/s in peripheral arteries.
• 😀 The pulse waveform is characterized by a percussion wave and a tidal wave, which are typically felt as a single pulse unless separated under certain conditions.
• 😀 The normal pulse waveform consists of two primary phases: the systolic phase (percussion and tidal waves) and the diastolic phase (dicrotic limb).
• 😀 In central arteries, the pulse is felt more distinctly, whereas peripheral arteries have a faster, spiked pulse due to lower compliance.
• 😀 Abnormal pulse waveforms can be classified into types such as pulsus parvas (low amplitude) and pulsus tardus (slow rising pulse).
• 😀 Pulsus parvas indicates a weak ventricular contraction or low blood volume in the left ventricle, often seen in shock or mitral stenosis.
• 😀 Pulsus tardus occurs when the pulse rises slowly, often seen in left bundle branch block due to delayed ventricular contraction.
• 😀 Pulsus bisferiens is characterized by two peaks in the systolic part of the pulse waveform and is associated with severe aortic regurgitation or hypertrophic cardiomyopathy.
• 😀 Pulsus paradoxus involves a significant drop in systolic blood pressure during inspiration (more than 10 mmHg), commonly seen in conditions like pericardial tamponade and severe obstructive lung disease.

Q & A

What is the arterial pulse, and how is it different from blood flow?

The arterial pulse is a pressure wave that travels along the arteries when the left ventricle contracts, causing the arterial wall to expand. It is different from blood flow because the pulse is a pressure wave, whose velocity is much higher than the velocity of blood flow.

Why is the pulse wave velocity different in central and peripheral arteries?

The pulse wave velocity is slower in central arteries (about 4 m/s) compared to peripheral arteries (around 16 m/s) because of the differences in vessel structure and compliance. Peripheral arteries are less compliant, making the pulse feel faster and more rapid.

What is the pressure waveform, and how is it assessed?

The pressure waveform is the contour or character of the pulse felt when palpating an artery. It reflects the pressure changes during the cardiac cycle, including the systolic and diastolic phases. It is assessed by palpating the carotid artery in central arteries or peripheral arteries.

What is the 'cacticalmain' phase, and which part of the pulse waveform does it represent?

The 'cacticalmain' phase refers to the overall normal pulse waveform, which is primarily seen during the systolic phase. This phase includes two waves: the percussion wave and the tidal wave, which are typically felt together but may be separated under certain conditions.

What factors influence the shape and amplitude of the pulse waveform?

Factors that influence the pulse waveform include stroke volume, ejection velocity, vascular compliance, and systemic vascular resistance. These factors affect the pulse's peak height, speed of rise, and overall shape.

What causes pulsus parvus, and when is it commonly observed?

Pulsus parvus refers to a low amplitude pulse, which occurs when there is low stroke volume or weak ventricular contraction. It is commonly seen in conditions like shock or mitral stenosis, where the amount of blood entering the left ventricle is reduced.

What is pulsus tardus, and which condition is it most associated with?

Pulsus tardus is a slowly rising pulse, typically seen in left bundle branch block. In this condition, the ventricles do not contract together, leading to a slower rise in pulse peak despite normal stroke volume.

What is an anacrotic pulse, and how does it differ from the normal pulse waveform?

An anacrotic pulse is a notched pulse waveform seen in aortic stenosis. It differs from a normal pulse in that the systolic rise shows a small notch due to slight obstruction in blood flow caused by the narrowed aortic valve.

How does aortic regurgitation lead to a water hammer pulse?

In aortic regurgitation, the aortic valve does not close properly, causing blood to flow back into the left ventricle. This leads to increased stroke volume, resulting in a rapid upstroke of the pulse waveform. Additionally, blood backflow causes a rapid fall in pressure, leading to a rapid downstroke.

What is pulsus bisferiens, and what are the conditions that can cause it?

Pulsus bisferiens is characterized by two peaks in the systolic phase of the pulse waveform. It can occur in severe aortic regurgitation, hypertrophic cardiomyopathy, or a combination of aortic stenosis and regurgitation. The condition is caused by increased stroke volume and ejection velocity, leading to a split in the pulse waveform.

What is pulsus paradoxus, and how is it measured?

Pulsus paradoxus is a condition where there is a greater than 10 mm Hg drop in systolic blood pressure during inspiration. It is measured by recording the blood pressure while slowly lowering the cuff pressure and noting the point where Korotkoff sounds are heard continuously during expiration and intermittently during inspiration.