1. Ch 12 Cardiovascular Physiology 31 October 2008 finish Section B The Heart Begin Section 3 The vascular System

2. Cardiac Output = Heart Rate X Stroke Volume CO = HR x SV 5L/min = 72 beat/min x 70 ml/beat

3. Figure 12.11 SA node cells spontaneously produce AP, do not have stable resting membrane potential, are Pacemaker cells

4. Intercalated Discs: mechanical attachments of cardiac myofibers to each other, with gap junctions (electrical synapses) to conduct AP

5. Fibrous connective tissue between atria and ventricles prevents the conduction of action potential. Only route is via AV node, bundle of His, bundle branches, Purkinje fibers, and to ventriclular myofibers. What prevents the AP from being conducted from ventricles back to atria?

6. Figure 12.14 Pacemaker Cells in Conducting System SA Node or Bundle of His Ectopic Pacemaker Location other than SA Node

7. Figure 12.22 Intrinsic Rate = 100 beat/min

8. Figure 12.23 Effect of “Beta blockers” NEEPIACh mAChR Effect of atropine Beta-adrenergic receptors

9. Figure 12.13 Cardiac Myofiber Plateau phase Cardiac Myofiber action potential

10. Figure 12.17 Calcium-induced calcium release

11. Who Cares? Mechanism of action of a Ca++ channel blocker? What effect on blood pressure?

12. Figure 12.18 1 st Heart Sound = Closure of Atrioventricular (AV) valves at beginning of Ventricular Systole 2nd Heart Sound = Closure of Semilunar valves at beginning of Ventricular Diastole

13. Figure 12.20 Systolic Diastolic Ejection Fraction = SV/EDV Atrial Fibrillation Ventricular Fibrillation & Defibrillation

15. Frank-Starling Law of the Heart FS LoH = SV is proportional to EDV Ventricular Function Curve