Cardiovascular Anatomy

(adapted from another slideshow on slideshare.com)

The Capillary Beds

The Cardiovascular System

Heart – the pump

Vasculature – the conduits

Pulmonary circuit

Systemic circuit

The Vasculature A closed system of vessels that moves blood around the bodyA closed system of vessels that moves blood around the body

Arterial vessels: aorta, arteries, arterioles (vascular resistance)Arterial vessels: aorta, arteries, arterioles (vascular resistance) Carry blood away from the heart to the:Carry blood away from the heart to the:

Capillary bedsCapillary beds

Venous vessels: venules, veins, venae cavae Venous vessels: venules, veins, venae cavae

Carry blood toward the heartCarry blood toward the heart

3 layers of an artery

1. Adventitia: tough covering.2. Media: muscle and elastic membrane3. Intima: delicate inner lining.

The Heart

A 4-chambered organ located in the middle mediastinum

CABG video 1:26ff

Cardiac bypass surgery.

Functional Purpose of the Heart

Four Chamber pump that provides blood supply to: Systemic circulation left

heart Pulmonary circulation right

heart

Right and left atria: receiving chambers

Right and left ventricles: pumping chambers

Suspended at the base by the great vessels

Heart WallEpicardium

Outer layer, inner visceral layer of pericardium

Myocardium Middle muscle

layer, interlacing bundles of fiber

Endocardium Inside of the heart,

covers valves

Myocardium

specialized musclePerforms the work of

the heartMakes up the

majority of the mass

Heart Wall

Figure 20.4

Cardiac Chambers

Right Atrium (RA)

Receives blood from the body or systemic venous circulation

Forms the right cardiac border

Receives blood from vena cava (SVC & IVC) and coronary sinus

Right Ventricle (RV)

Provides blood flow to the pulmonary circuit

Low pressure pump <35 mmHg

Crescent-shaped wraps around the LV

Most anterior heart structure

Left Atrium (LA)Receives blood from

the lungs (oxygenated)

Smooth walled except appendage

Most posterior cardiac chamber

Receive blood through right and left pulmonary veins

Left Ventricle (LV)

Provides blood flow to the systemic circuit

High pressure pump >100 mmHg

Egg shaped (ellipse)

Forms the left cardiac border

Structural Differences between the Left and Right Ventricles

Figure 20.7a-c

Cardiac TissuesAnnuli fibrosi

Non-conducting fibrous connective tissue

Referred to as the skeleton

Forms support for the valves tissue (annulus)

Separates the atria and ventricles and ventricles and great vessels

Valves of the Heart

Figure 20.8a

Atrioventricular: Mitral and Tricuspid

Separate the atria and their respective ventricles

Tricuspid, Bicuspid

Attached at the base to the annulus and at the tips to the papillary muscles via chordae tendinea

Semilunar: Aortic and PulmonicSeparate the

ventricles and their respective arteries

Three cusp, attached at the base to the annulus

Pressure sensitive valve, opening and closing activated by change in pressure

Coronary ArteriesSupplies blood supply

to the heartTwo primary arteries

from the aortaLeft

Left Main Left Anterior Descending Circumflex

Right Right Posterior Descending

Heart Casts - Muscle Removed

Left MainLAD

DiagonalSeptal perforators

Circumflex

Left atrial branch

Obtuse Marginal

Right Coronary ArteryRA, RV, Inferior LV, SA Node, AV NodeConus branch (RVOT)Sinus node branch (SA node, RA)RV BranchesAcute Marginal branches (RV)AV nodal artery (AV node, IAS)Posterior descending artery (inferior IVS)Left ventricular branch-PLA’s (inferior LV)

Conus branch

Sinus node branch

Acute Marginal Posterior descending artery

Left ventricular branch

RV branch

RAO

Circumflex LAD

DiagonalSeptal

LAD

Evolution of fibrous plaque

LDLMonocyte

endothelium

Cell adhesion factors

Foam Cells

1

1. LDL enters 2. & Oxidizes

3. Monocytes adhere & 4. cross intima become macrophages

macrophage

5. Macrophages Eat Fat become Foam cells

6. muscle cells multiply & 7. enter intima

8. Muscle cells die & harden plaque -Calcium develops

Fuster V, et al. Fuster V, et al. N Eng J MedN Eng J Med 1992;326:311-318. 2. Photos courtesy of Boehringer Ingleheim International GmbH, by Lennart 1992;326:311-318. 2. Photos courtesy of Boehringer Ingleheim International GmbH, by Lennart Nilsson Nilsson

Braunwald E, et al. 2002 http://www.acc.org/clinical/guidelines/unstable/unstable.pdfBraunwald E, et al. 2002 http://www.acc.org/clinical/guidelines/unstable/unstable.pdf

Coronary Artery Disease

Aortic valveNormal aortic valve

area is 2.5 to 4.0 cm2

Diseased aortic valve. Narrowed opening.