Diastole

Heart performance during ventricular diastole: early diastole is a suction mechanism that draws blood 'down' from the left atrium (pink) and right atrium (blue) into each of the two ventricles. Then, in late ventricular diastole, the two atrial chambers begin to contract (atrial systole), forcing additional blood flow into the ventricles.
A Wiggers diagram, showing various events during diastole. During early ventricular diastole—see vertical bar marked "Isovolumetric relaxation"—pressure in each ventricle (light-blue trace) begins to drop quickly from the wave height reached during systole. When ventricular pressures fall below those in the atrial chambers the atrioventricular (mitral and tricuspid) valves open, causing blood volume (red trace) in the atria to flow into the ventricles. + In late ventricular diastole, the two atrial chambers begin to contract (atrial systole), causing blood pressure in both atria to increase and forcing additional blood volume into the ventricles. This beginning of the atrial systole is known as the atrial kick—see "Ventricular volume" trace (red) directly above the P-wave in the electrocardiogram trace (dark-blue).

Part of the cardiac cycle during which the heart refills with blood after the emptying is done during systole .

- Diastole
Heart performance during ventricular diastole: early diastole is a suction mechanism that draws blood 'down' from the left atrium (pink) and right atrium (blue) into each of the two ventricles. Then, in late ventricular diastole, the two atrial chambers begin to contract (atrial systole), forcing additional blood flow into the ventricles.

153 related topics

Relevance

A healthcare worker measuring blood pressure using a sphygmomanometer.

Blood pressure

Pressure of circulating blood against the walls of blood vessels.

Pressure of circulating blood against the walls of blood vessels.

A healthcare worker measuring blood pressure using a sphygmomanometer.
A digital sphygmomanometer used for measuring blood pressure
Overview of main complications of persistent high blood pressure
Cardiac systole and diastole
Blood flow velocity waveforms in the central retinal artery (red) and vein (blue), measured by laser Doppler imaging in the eye fundus of a healthy volunteer.
Schematic of pressures in the circulation
A schematic representation of the arterial pressure waveform over one cardiac cycle. The notch in the curve is associated with closing of the aortic valve.
Taking blood pressure with a sphygmomanometer

Blood pressure is usually expressed in terms of the systolic pressure (maximum pressure during one heartbeat) over diastolic pressure (minimum pressure between two heartbeats) in the cardiac cycle.

Computer generated animation of cut section of the human heart showing both ventricles.

Ventricle (heart)

One of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs.

One of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs.

Computer generated animation of cut section of the human heart showing both ventricles.
Heart section showing ventricles and ventricular septum
Wiggers diagram of various events of a cardiac cycle, showing left ventricular volume as a red trace.
Partial Wiggers diagram. Red = aortic pressure Blue = left ventricular pressure Yellow = left atrial pressure.

During diastole, the ventricles relax and fill with blood again.

MRI video of a teen's heart beating.

Cardiac cycle

Performance of the human heart from the beginning of one heartbeat to the beginning of the next.

Performance of the human heart from the beginning of one heartbeat to the beginning of the next.

MRI video of a teen's heart beating.
The cycle diagram depicts one heartbeat of the continuously repeating cardiac cycle, namely: ventricular diastole followed by ventricular systole, etc.—while coordinating with atrial systole followed by atrial diastole, etc. The cycle also correlates to key electrocardiogram tracings: the T wave (which indicates ventricular diastole); the P wave (atrial systole); and the QRS 'spikes' complex (ventricular systole)—all shown as color purple-in-black segments.
The Cardiac Cycle: Valve Positions, Blood Flow, and ECG
The parts of a QRS complex and adjacent deflections. Re the cardiac cycle, atrial systole begins at the P wave; ventricular systole begins at the Q deflection of the QRS complex.
A Wiggers diagram illustrate events and details of the cardiac cycle with electrographic trace lines, which depict (vertical) changes in a parameter's value as time elapses left-to-right. The ventricular "Diastole", or relaxation, begins with "Isovolumic relaxation", then proceeds through three sub-stages of inflow, namely: "Rapid inflow", "Diastasis", and "Atrial systole". (During the "Diastole" period, the "Ventricular volume" increases (see red-line tracing), beginning after the vertical bar at "Aortic valve closes" and ending with the vertical bar at R in the QRS complex). + The ventricular "Systole", or contraction, begins with "Isovolumic contraction", i.e., with the vertical bar at "A -V valve closes"; it ends with completing the "Ejection" stage at the bar at "Aortic valve closes". During "Ejection" stage, the (red-line) tracing of "Ventricular volume" falls to its least amount (see ejection fraction) as the ventricles pump blood to the pulmonary arteries and to the aorta.
Diastole (at right) normally refers to atria and ventricles at relaxation and expansion together—while refilling with blood returning to the heart. Systole (left) typically refers to ventricular systole, during which the ventricles are pumping (or ejecting) blood out of the heart through the aorta and the pulmonary veins.
CGI animated graphic of the human heart, sectioned, with motions and timing synced with the Wiggers diagram. The section shows: 1) the opened ventricles contracting once per heartbeat—that is, once per each cardiac cycle; 2) the (partly obscured) mitral valve of the left heart; 3) the tricuspid and pulmonary valves of the right heart—note these paired valves open and close oppositely. + (The aortic valve of the left heart is located below the pulmonary valve, and is completely obscured.) The (unsectioned) atria are seen above the ventricles.
Cardiac diastole: Both AV valves (tricuspid in the right heart (light-blue), mitral in the left heart (pink)) are open to enable blood to flow directly into both left and right ventricles, where it is collected for the next contraction.
Cardiac (ventricular) systole: Both AV valves (tricuspid in the right heart (light-blue), mitral in the left heart (pink)) are closed by back-pressure as the ventricles are contracted and their blood volumes are ejected through the newly-opened pulmonary valve (dark-blue arrow) and aortic valve (dark-red arrow) into the pulmonary trunk and aorta respectively.

It consists of two periods: one during which the heart muscle relaxes and refills with blood, called diastole, following a period of robust contraction and pumping of blood, called systole.

Anterior (frontal) view of the opened heart. White arrows indicate normal blood flow. (Tricuspid valve labeled at bottom left.)

Tricuspid valve

On the right dorsal side of the mammalian heart, at the superior portion of the right ventricle.

On the right dorsal side of the mammalian heart, at the superior portion of the right ventricle.

Anterior (frontal) view of the opened heart. White arrows indicate normal blood flow. (Tricuspid valve labeled at bottom left.)
Tricuspid valve. Deep dissection.
Tricuspid valve marked in yellow.
Diagram of tricuspid insufficiency/regurgitation. Marked in black arrow.

Tricuspid regurgitation can result in increased ventricular preload because the blood refluxed back into the atrium is added to the volume of blood that must be pumped back into the ventricle during the next cycle of ventricular diastole.

The cardiac cycle at the point of beginning a ventricular systole, or contraction: 1) newly oxygenated blood (red arrow) in the left ventricle begins pulsing through the aortic valve to supply all body systems; 2) oxygen-depleted blood (blue arrow) in the right ventricle begins pulsing through the pulmonic (pulmonary) valve en route to the lungs for reoxygenation.

Systole

Part of the cardiac cycle during which some chambers of the heart muscle contract after refilling with blood.

Part of the cardiac cycle during which some chambers of the heart muscle contract after refilling with blood.

The cardiac cycle at the point of beginning a ventricular systole, or contraction: 1) newly oxygenated blood (red arrow) in the left ventricle begins pulsing through the aortic valve to supply all body systems; 2) oxygen-depleted blood (blue arrow) in the right ventricle begins pulsing through the pulmonic (pulmonary) valve en route to the lungs for reoxygenation.
Electrical waves track a systole (a contraction) of the heart. The end-point of the P wave depolarization is the start-point of the atrial stage of systole. The ventricular stage of systole begins at the R peak of the QRS wave complex; the T wave indicates the end of ventricular contraction, after which ventricular relaxation (ventricular diastole) begins.
The cardiac cycle at beginning of atrial systole: The left (red) and right (blue) ventricles begin to fill during ventricular diastole. Then, after tracing the P wave of the ECG, the two atria begin contracting (systole), pulsing blood under pressure into the ventricles.
A Wiggers diagram, showing various events during systole (here primarily displayed as ventricular systole, or ventricular contraction). The very short interval (about 0.03 second) of isovolumetric, or fixed-volume, contraction begins (see upper left) at the R peak of the QRS complex on the electrocardiogram graph-line. + Ejection phase begins immediately after isovolumetric contraction—ventricular volume (red graph-line) begins to decrease as ventricular pressure (light blue graph-line) continues to increase; then pressure drops as it enters diastole.

When, in late ventricular diastole, the atrial chambers contract, they send blood down to the larger, lower ventricle chambers.

Front view of heart showing the atria

Atrium (heart)

One of two upper chambers in the heart that receives blood from the circulatory system.

One of two upper chambers in the heart that receives blood from the circulatory system.

Front view of heart showing the atria
Right heart anatomy
left atrial appendage shown at upper right
CT scan of the chest showing a thrombus in the left atrial appendage (left: axial plane, right: coronal plane)

During the cardiac cycle the atria receive blood while relaxed in diastole, then contract in systole to move blood to the ventricles.

Anterior (frontal) view of the opened heart. White arrows indicate normal blood flow. (Mitral valve labeled at center right.)

Mitral valve

One of the four heart valves.

One of the four heart valves.

Anterior (frontal) view of the opened heart. White arrows indicate normal blood flow. (Mitral valve labeled at center right.)
Operative view of the mitral valve with a chordal rupture "fail" of the anterior leaflet
3D Medical Animation still shot of Mitral Valve Prolapse
The left side of the heart. The mitral valve, as well as the chordae tendinae are visible as white strings. These connect to the papillary muscles visible attaching to the muscular ventricle.
Mitral annulus
The human heart, viewed from the front. The mitral valve is visible on the right as the "bicuspid valve"
The chest, showing surface relations of bones, lungs (purple), pleura (blue), and heart (red). Heart valves are labeled with "B", "T", "A", and "P".
Mitral valve, viewed in a cadaver specimen from within the left atrium.

In normal conditions, blood flows through an open mitral valve during diastole with contraction of the left atrium, and the mitral valve closes during systole with contraction of the left ventricle.

In those with HFpEF, the left ventricle of the heart (large chamber on right side of the picture) is stiffened and has impaired relaxation after pumping blood out of the heart.

Heart failure with preserved ejection fraction

Form of heart failure in which the ejection fraction – the percentage of the volume of blood ejected from the left ventricle with each heartbeat divided by the volume of blood when the left ventricle is maximally filled – is normal, defined as greater than 50%; this may be measured by echocardiography or cardiac catheterization.

Form of heart failure in which the ejection fraction – the percentage of the volume of blood ejected from the left ventricle with each heartbeat divided by the volume of blood when the left ventricle is maximally filled – is normal, defined as greater than 50%; this may be measured by echocardiography or cardiac catheterization.

In those with HFpEF, the left ventricle of the heart (large chamber on right side of the picture) is stiffened and has impaired relaxation after pumping blood out of the heart.
Wiggers diagram, depicting the cardiac cycle. Two complete cycles are illustrated.
End Diastolic Pressure Volume Relationship

HFpEF is characterized by abnormal diastolic function: there is an increase in the stiffness of the left ventricle, which causes a decrease in left ventricular relaxation during diastole, with resultant increased pressure and/or impaired filling.

Major factors influencing stroke volume – Multiple factors impact preload, afterload, and contractility, and are the major considerations influencing SV.

Stroke volume

Volume of blood pumped from the left ventricle per beat.

Volume of blood pumped from the left ventricle per beat.

Major factors influencing stroke volume – Multiple factors impact preload, afterload, and contractility, and are the major considerations influencing SV.

Reduced heart rate prolongs ventricular diastole (filling), increasing end-diastolic volume, and ultimately allowing more blood to be ejected.

Heart

Muscular organ in most animals that pumps blood through the blood vessels of the circulatory system.

Muscular organ in most animals that pumps blood through the blood vessels of the circulatory system.

Human heart during an autopsy
Computer-generated animation of a beating human heart
The human heart is in the middle of the thorax, with its apex pointing to the left.
Heart being dissected showing right and left ventricles, from above
Frontal section showing papillary muscles attached to the tricuspid valve on the right and to the mitral valve on the left via chordae tendineae.
Layers of the heart wall, including visceral and parietal pericardium
The swirling pattern of myocardium helps the heart pump effectively
Arterial supply to the heart (red), with other areas labelled (blue).
Autonomic innervation of the heart
Development of the human heart during the first eight weeks (top) and the formation of the heart chambers (bottom). In this figure, the blue and red colors represent blood inflow and outflow (not venous and arterial blood). Initially, all venous blood flows from the tail/atria to the ventricles/head, a very different pattern from that of an adult.
Blood flow through the valves
The cardiac cycle as correlated to the ECG
The x-axis reflects time with a recording of the heart sounds. The y-axis represents pressure.
Transmission of a cardiac action potential through the heart's conduction system
Conduction system of the heart
The prepotential is due to a slow influx of sodium ions until the threshold is reached followed by a rapid depolarization and repolarization. The prepotential accounts for the membrane reaching threshold and initiates the spontaneous depolarization and contraction of the cell; there is no resting potential.
3D echocardiogram showing the mitral valve (right), tricuspid and mitral valves (top left) and aortic valve (top right).
The closure of the heart valves causes the heart sounds.
Cardiac cycle shown against ECG
Heart and its blood vessels, by Leonardo da Vinci, 15th century
Animated heart
Elize Ryd making a heart sign at a concert in 2018
The tube-like heart (green) of the mosquito Anopheles gambiae extends horizontally across the body, interlinked with the diamond-shaped wing muscles (also green) and surrounded by pericardial cells (red). Blue depicts cell nuclei.
Basic arthropod body structure – heart shown in red
The human heart viewed from the front
The human heart viewed from behind
The coronary circulation
The human heart viewed from the front and from behind
Frontal section of the human heart
An anatomical specimen of the heart
Heart illustration with circulatory system
Animated Heart 3d Model Rendered in Computer

The period of time during which the ventricles contract, forcing blood out into the aorta and main pulmonary artery, is known as systole, while the period during which the ventricles relax and refill with blood is known as diastole.