CARDIOVASCULAR MODULE - under construction

General Introduction

For a general introduction see the start of the THORAX module.

Gross dissection Views

The gross dissection images on this site were photographed in 2003 & 2004 by Dr Barbara Kraszpulska with the technical help of Jeffrey Altemus, under the auspices of the Department of Neurobiology & Anatomy, West Virginia University. She holds the author's copyright.

Dissection views

(i) That you can see inside someone in this manner is only thanks to his/her generosity in allowing this use of his body after death. Respect the person's intent that you should be able to learn so as to be better at knowing and helping the living.

(ii) The appearance of the embalmed tissues and organs changes over time, so that in the lab you may meet darker shades of tan and brown.

(iii) In order to view the structures, usually several layers of connective tissue have had to be removed, so the images do not show how well and tightly our organs are packed in and fastened together.

(iv) One's first thought should be on orientation - How is the person lying? Face down/up/ or on side? What region am I looking at, and from what direction? Front back, left side, etc. [Know the technical names, supine, left lateral, etc.]

The first image of a series has a white stick figure to indicate orientation. . Thorax & Abdomen (anterior) - Orientation

(v) Later Figs then are labelled to show major structures, vascular and nervous structures, and other items of interest.
Set in the text close to a dissection view may be a link to a relevant Powerpoint Fig from the Theory lectures.

(vi) At home, the images may take up to a minute to download, depending on your connection to the Web. They are in .jpg format which needs a viewer of some kind (Paint, Adobe, Camedia, etc.).
If you save the images all to one folder on your own computer, your viewer subsequently will give you a comprehensive showing of thumbnails or files that you can select from rapidly. Although, the links from the master text will not work, you can print that out and read along while looking at the images. Later, when I'm sure of how many .ppt and .jpg Figs I need to use, I may number them consecutively to connect them better with the text.


How we'll handle the list of structures to be known for the lab differs from the Bones list. At the end of this module will be the complete list for you to go through to see if you have a clear mental image of what each structure looks like in the lab and what its relations are. But before then the list will be broken up into the structures for particular thoracic regions, here the Cardiovascular System.


NBAN  206  MODULE  II  
 Cardiovascular System . 
Lab Assignments
Structures to be identified for Anatomy 206 taken from Guy Lessons 41,42,43,44

HEART
Parietal pericardium - - Visceral pericardium
Vessels on the outside of the heart:-

  • Left coronary artery
  • Left anterior descending artery (LAD) / anterior interventricular
  • Right coronary artery
  • Coronary sinus
  • Great cardiac vein - -

    Great vessels entering and leaving the heart:-

  • Superior vena cava (SVC)
  • Inferior vena cava (IVC)
  • Pulmonary trunk
  • Pulmonary arteries
  • Pulmonary veins
  • Aorta

    Heart
    Atria (right and left) - - Ventricles (right and left) - - Interventricular septum - - Atrio-ventricular valves Mitral, Tricuspid - - Chordae tendinae - - Papillary muscles - - Semilunar valves Aortic, Pulmonary

    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    Left lung
    Superior and inferior lobes - - Oblique fissure - - Cardiac notch - - aortic-arch indentation

  • Introduction to the Cardiovascular System

    The approach will be to first look at the heart in the chest and connected to the great vessels. Among other aspects, this gives us the natural orientation of the heart as we think about it when out of the body. Then, we'll examine the heart out of the body, in various orientations and with the chambers opened up to see internal structures. Lastly, we shall think more systemically and follow some of the vessels as they distribute blood to different regions of the body.

    We've seen our first dissection image before, but now we'll focus on the heart. Note the whiteish heart surface (the visceral pericardium), visible because the pericardial sac of parietal pericardium has been cut away anteriorly. The heart chambers seen from the front are the right ventricle and above it and to the right the smaller right atrium, with the superior vena cava (SVC) descending into it. To the left of the SVC is the bigger, whiter, ascending aorta. . . Anterior heart in situ

    Although we just saw the heart pointing down and to the left, the next anterior/frontal view makes clear this inclination of the heart, with the apex well to the left of the midline. The pericardium has been totally stripped away, and the heart lifted off the diaphragm. To lift it, where the inferior vena cava joined the bottom of the right ventricle has been cut. On the cadaver, find where the IVC opens up through the diaphragm - there may be clotted blood inside and holding the IVC open. . Heart alone - frontal view

    The orientation has changed from the last image, and the heart is still in its pericardial sac. The leftward extension of the pericardium creates the indentation - cardiac notch - in the left lung's inferior lobe, and the protrusion of the left ventricle makes the left lung smaller than the right. The small protruding 'tongue' of lung created in front of the notch is the lingula. . . Heart, lungs and cardiac notch

    Another view that we have seen before shows the right side of the mediastinum. We see the two large brachiocephalic veins coming together to form the superior vena cava, which is then joined by the azygous vein, before entering the right atrium . . Superior vena cava

    This is a new image - of the left side of the mediastinum, with the heart exposed by peeling back the parietal pericardium. Note how the aorta curves left as the aortic arch, before turning inferiorly toward the diaphragm. . Left mediastinum

    Emerging from the heart to the left of the aorta is the pulmonary trunk carrying blood out of the right ventricle. The left ventricle is the larger so that we can see it here on the posterior/back side of the heart (and also on the next-to-last image of the right side of the mediastinum, but unlabelled). . Pulmonary trunk

    This is an anterior view with the heart, held more upright that it is in situ. We see the two right-side chambers with the furrow - coronary sinus - between them. A little of the left ventricle is to be seen. {A prominent white artery (LAD) rides on the wall - septum - between Rt & Lft ventricles.] The order of great vessels from right to left is SVC (inconspicuous), aorta (ascending) in the middle, and pulmonary trunk on the left. The right ventricle has been opened, and the probe shows that blood flows from it into the pulmonary trunk. . . Great vessels & Rt ventricle

    An orientation that you need to return to time and again in the lab. [This superior view should have been rotated 90 degrees to the right to restore the correct left-right order of great vessels.] Note the very thin wall of the SVC, the thick wall of the aorta (think garden hose), and the quite thick wall of the pulmonary trunk. On some hearts the pulmonary trunk may have been cut further from the heart, and already have split into one or both pulmonary arteries. The Rt PA passes under the arch of the aorta; and on models and in the text figs. will be colored blue because it carries de-oxygenated blood. . . Heart - superior view

    Yet another orientation - this time both right atrium and right ventricle have been opened. Note again the order of great vessels. The probe entered the right atrium via the SVC, but leaves where the IVC came in. So, SVC and IVC are in line on opposite sides of the right atrium . Rt atrium with SVC and IVC

    In this posterior view, the copyright is by the apex of the opened left ventricle. Above the left ventricle, and separated by more coronary sulcus, is the left atrium. The blood received from the left atrium is squeezed out by the left venticle into the aorta. The probe marks the line of flow, but the probe's point comes down onto the thick left ventricular wall. (The left ventricle is the larger chamber and has the thicker wall.) . Left ventricle & aorta

    This anterior view shows the right-side chambers, with the right ventricle wide open and leading into the opened-up pulmonary trunk. Two of the three flaps/leaflets/cusps of the pulmonary semilunar valve are visible. Only the one on the right is marked with the probe inserted behind it. The valve keeps blood flowing to the lungs, by preventing backflow into the ventricle. There will be a similar aortic valve. Both valves may also be seen by looking down into the vessels from on top of the heart. . Pulmonary valve

    This view of another heart's posterior side need to be tipped very slightly counterclockwise, and with the top a little towards you. Then, the inferior vena cava (IVC) would enter vertically the right atrium (hardly to be seen), and the apex of the left ventricle would point slightly downwards. Otherwise, the orientation is true to life, and shows the four pulmonary veins entering the left atrium carrying oxygenated blood. The pulmonary trunk has branched into Left & right pulmonary arteries. The right PA has already started to branch, and also almost completely obscures the superior vena cava. . Pulmonary veins & arteries

    This view complements the previous one of the same un-dissected heart, but shows the anterior face and is tipped about 45 degrees clockwise. Aside from the continuity of the right ventricle with the pulmonary trunk, note how the right ventricle dominates the frontal aspect. The auricle is a small ear-like extension to the atrium. Above the right pulmonary veins, try to find the now almost hidden right pulmonary artery that was clearly visible in the previous posterior view. . Auricle & Pulmonary veins

    This superior view looks down into the opened left atrium. Below it, but partly visible is the left ventricle. The two edges of the cusps/leaflets of the left atrio-ventricular valve are outlined in yellow and orange. (The short, precise name for the valve is the mitral valve.) The edges of both AV valves are surprisingly knobly, but the valves still function. Note the few severed strands of chordae tendinae hanging from the anterior (here, upper) cusp. . Mitral/Bicuspid valve

    This anterior view has the right ventricle open, with the left ventricle behind it. (The left ventricle has deep cut exposing the thickness of its wall.) Thus, inside the right ventricle we're looking at the thick wall (interventricular septum) separating it from the left ventricle. On the right face of this wall runs aprominent part of the heart's conductiong system - the moderator band, with the probe inserted behind it. Its branches to spread impulses elsewhere in the ventricular wall (starting with papillary muscles) can be seen. . Interventricular septum & moderator band

    In this familiar left lateral view of the heart in situ, note that, although the parietal pericardium has been cut away, the visceral pericardium is thick and laden with fat. This obscures how the LAD runs almost to the apex of the heart - we see only its early segment. On the front of the heart, the right coronary artery has been lifted out of the sulcus. . LAD & Right coronary artery

    In this anterior view we see the two right-side chambers, with the right coronary artery running between them. Where it attaches to the ascending aorta is concealed, but is marked by where the blue needle hold down a piece of pulmonary trunk wall. Sometimes, the attachment of the coronary arteries to the aorta is more easily found by looking inside the aorta for the two small holes, and then feeeling around the outside for the vessels. . Right coronary artery

    The left coronary artery joins the ascending aorta on the latter's posterior side, but it runs less than a centimeter before branching into the LAD (here mostly hidden behing a thumb), and the circumflex artery. As its name indicates, the circumflex A bends around to serve the back of the heart, occupied mostly by left ventricle. The short course of the left coronary artery is obscured by fat, and here by the auricle (ear) of the left atrium. In the lab one has to burrow for it. (The label on the aorta should be a little higher, because it is partly on the right pulmonary artery.) . Left coronary artery . . . . Coronary arteries ppt . .

    Posterior heart. Having served the capillaries of the heart, the blood collects in its venous vessels, and finally in the coronary sinus. The coronary sinus is entirely posterior, lying between the left atrium and left ventricle. i.e, the coronary sinus lies in the posterior part of the coronary sulcus (beware the distinction). The sinus is either dark, soft, and baggy, or dark but hard from hardened blood inside. A major tributary of the coronary sinus is the great cardiac vein on the heart's left lateral face. It is hard to disentangle visually from the branches of the left coronary A, but it must connect with the start of the sinus; the end of the sinus - into the right atrium - cannot be seen in this view. In the lab, look in the right atrium for the the opening of the sinus. Push a probe into it and see it moving the sinus. . . Coronary sinus.ppt . . . . Coronary sinus . .

    Some of the above lab exercises - with probes, etc, - are in the text do-it-yourself guide to learning the heart. Print it out, and try it in the lab. . . Heartfelt

    Although going way outside the thorax, some major examples of vessels served by the heart (the 'vascular' of the cardiovascular system) will be looked at now in the lab. [Other vessels will be seen later as we cover particular organs, such as the kidneys, spleen, brain, etc.] So first, a list of the vessels to be known for the 'Thorax' lab test.

    Major arteries of Systemic Circulation
    

    Ascending aorta - - Coronary vessels of the heart - - Arch of aorta - - Brachiocephalic trunk - - Right common carotid a. (to head and neck) - - Right subclavian a.(to right upper limb) - - Left common carotid artery (to head and neck) - - Left subclavian artery(to left upper limb) - -

    Upper limb blood supply (same on both sides)
    Right or left subclavian aa. (same on both sides) - - Axillary aa. - - Brachial aa. - - Radial aa. and Ulnar a. - -

    Thoracic wall blood supply
    Descending thoracic aorta (only one of these) - - Intercostal aa. (same on both sides)

    Pelvis & Lower Limb Blood Supply (Same on both sides)
    Common iliac aa. - - Internal iliac aa. (to the pelvis) - - External iliac a. (main blood supply to the lower limb) - -Femoral aa.

    Major VEINS of systemic circulation

    Superior vena cava (only one of these) collects venous blood from all veins above the diaphragm - -
    Tributaries to the superior vena cava(same on both sides)

  • Brachiocephalic vv. - -
  • Subclavian vv. - -
  • Internal jugular vv.

    Inferior vena cava (only one of these) collects all venous blood from veins below the diaphragm

  • Note, below the covered head, the line of the left clavicle. Under it the left subclavian A runs from the arch of the aorta into the axilla. There, the artery is briefly the before continuing into the arm for an extensive run as the brachial A. Pull on the brachial A to establish that it is continuous with the axillary and subclavian AAs all the way back to the aorta. . Subclavian, axillary & brachial AAS . . . . Arterial distribution ppt . .

    This orienting view shows the left upper extremity, divided into arm, forearm, and hand. Remembering from the Skeletal Module, critical to knowing where the ulna and radius bones lie is that the radius is lateral on the thumb side, in the anatomical position. The cubital fossa region lies slightly below the ELBOW marker here. . . Anterior arm and forearm . . . . Arteries to hand ppt

    The next dissection image is the same, but marked now for the brachial artery's division into the radial and ulnar arteries. Note that the median nerve is white but more solid, and can be traced back (by sight and gentle pulling) to the complicated, interconnected brachial plexus in the axilla. . Brachial, radial & ulnar AAs

    The first vessels to leave the aorta are the coronary arteries from the ascending aorta. Then three major ones come off in quick succession: brachiocephalic trunk/artery, left commaon carotid A, and left subclavian A. In this familiar lateral mediastinal view, the cut-off brachiocephalic trunk and left subclavian A are visible, but the left common carotid A is hidden. . Brachiocephalic trunk

    On the previous view, we saw the thoracic descending aorta. (Here the feet are still to the left, but the body's orientation has shifted 45o counterclockwise. We are looking at the back (retroperitoneal region) of the abdomen and pelvis.) The aorta has passed through the diaphragm to become the abdominal aorta. To its right runs the darker inferior vena cava (IVC). The abdominal aorta and the IVC are protected by attaching to the front of the vertebral bodies, while on either side the kidneys nestle in the lower rib-cage (but they are abdominal, not thoracic structures). The abdominal aorta finally branches into right and left common iliac arteries, which each then soon divides again (see next). Abdominal aorta & IVC

    As for the head with its intricate bilateral structure, the pelvis lends itself to a hemisection view. A mid-sagittal cut through the pelvis provided this right half, viewed looking outward from the midline. We shall return to such views later in the Pelvis Module, but now only the major vessels are of interest. . Pelvic hemisection - orientation

    The same basic image now shows how the Right common iliac artery divides into an internal iliac A serving pelvic organs, and an external iliac A that continues on through the inguinal region to become the Right femoral A once it reaches the thigh. . Iliac and femoral arteries

    Here we concentrate on major veins of the lower abdomen: the IVC (darker and to the right of the abdominal aorta); the Left common iliac vein but its branching is hidden under the Left common iliac A; and the Right external iliac vein whose origin is hidden under the Right common iliac artery. [Side and continuity with IVC or aorta are the keys to identifying these VVs & AAs.] . Iliac veins

    This Fig should really follow the next-to-last one for the Femoral A, but is placed here because the left-to-right orientation is switched from the previous images. . Ext Iliac & Femoral AAs

    The U Michigan view, next, of vessels of the neck shows a clear dissection of the major arteries and veins just superior to the heart. Our dissections are much less complete, and more hunting will be needed. U Michigan vessels of neck