Blood enters the Right Atrium (RA) from the Superior Vena Cava (SVC), the Inferior Vena Cava (IVC), and the Coronary sinus. Blood from the RA enters the Right Ventricle (RV) through the Tricuspid valve. The RV squeezes the blood through the Pulmonary valve into the pulmonary circulation. Returning from the lungs via the Pulmonary veins, blood enters the Left Atrium (LA) crosses the Mitral valve to enter the Left Ventricle, and is then squeezed into the aorta through the aortic valve.
Conduction System
SA Þ AV Þ His/Purkinje fibers. The delay at the AV node allows (1) the ventricles to finish filling and (2) serves as a protective mechanism if the SA node fires too rapidly (the AV node will max out)
ECG
(EKG)
P wave
atrial depolarization
QRS complex
ventricular depolarization and atrial repolarization
T wave
ventricular repolarization
Some Diseases
CHF
LV has ß CO (cardiac output) which leads to Ý pressure in the LA, and then up to the lungs. The Ý pressure I the lungs feedsback to RV and then to the RA which ultimately leads to venous distention. Thats why patients get SOB (pulmonary edema) and when RV fails, patients get dependent edema.
HTN
very common disease, but only 27% of patients are recognized and treated; leads to LV hypertrophy and heart failure
Coronary Artery Disease
cholesterol plaques block arteries Þ angina Þ MI
Congenital Heart Diseases
shunts etc.; will be covered by the Pediatric Cardiologists this committee