anatomy of Left atrium and left ventricle of the human heart

left atrium- interior of auricle is rough due to musculi pectinate, rest chamber is smooth. fossa lunate is present on septal wall. 4 pulmonary veins open on posterior wall.
left ventricle- inflowing part is rough due to mitral or bicuspid valve apparatus, trabeculae carneae.
outflowing part is smooth called infundibulum. ascending aorta starts from infundibulum. aortic valve guards opening of ascending aorta

1. Anatomy of Left atrium, left ventricle of the heart Dr. Karle Geetanjali Professor, PMT’s ayurved college, shevgaon , Maharashtra.

2. Introduction - The left atrium is one of the four chambers of the heart, located on the left posterior side. It receives oxygenated blood returning from the lungs and pump it to left ventricle of the heart. The walls of the left atrium are slightly thicker than the walls of the right atrium. Oxygen-rich blood from the lungs enters the left atrium through the pulmonary vein. The blood is then pumped into the left ventricle through the mitral valve.

3. External feature of left atrium- Left atrium forms maximum part of base (posterior surface) of the heart, left auricle contributes in the formation of left surface and small part of anterior surface of heart. 4 pulmonary veins 2- right , 2- left called as superior and inferior pulmonary veins are attached to posterior wall of left atrium .

4. Internal structure of left atrium- Left atrium is smooth except its auricular part. Musculi pectinate are present only in auricle 4 pulmonary veins opens on posterior wall of left atrium, 2 on right 2 on left side. On septal wall there is depressed fossa called as fossa lunate, opposite to fossa ovalis in rt atrium

5. Clinical anatomy - Left atrial hypertrophy Arterial flutters Fossa lunate is site for thrombus formation

6. Left ventricle- introduction- Left ventricle receives oxygenated blood from left atrium through bicuspid (Mitral valve) Left ventricle pumps blood to systemic circulation through aorta

7. External features of left ventricle- Apex of heart is formed by Left ventricle and it is located in left 5 th intercostal space 9cm from midline Left ventricle forms anterior, left and inferior surfaces of heart.

8. Internal structure of left ventricle- The walls of left ventricle are 3 times thicker than right ventricle Interior of left ventricle is divided into 2 parts – 1) inflowing rough part 2) outflowing smooth part - infundibulum

9. 1) Inflowing part- It is rough due to Trabeculae corneae Bicuspid valve apparatus formed by – papillary muscles- anterior and posterior Chordae tendineae 2 cusps- anterior and posterior

10. 2) Outflowing part- Out flowing part is smooth called as aortic infundibulum Opening of aorta is present on upper end of infundibulum The opening of aorta is guarded by semilunar valve, having 3 cusps – right, left and posterior Right and left coronary arteries arises from rt and left sinuses of aortic valve

11. Aortic valve-

12. Clinical anatomy - Left ventricular hypertrophy- due to aortic valve stenosis

13. Thank you !!! Special thanks to my student Dr. Kishor Pawar for diagrams of heart, left atrium, left ventricle and diagram of aortic valve.