I. Cardiovascular system- Rate, Rhythm and VolumeA. Rate + Rhythm = OutputB. NutritionC. Cardiovascular systemD. Cardiac AnatomyE. Histology of Cardiac MuscleF. Electrical impulses of the HeartG. Cardiac PhysiologyH. Blood FlowE. Histology of Cardiac muscle1. striated- has a sarcomere like in skeletal musclea) Troponin has to complex with Calcium still, but it is a different type of troponin, troponin I (specific to the heart)b) Troponin I can help you recognize a heart attack, assay of this allows us to see that when it is apparent in the blood supply, we know that someone has had a heart attack (can determine the extent of a heart attack from amount of this in blood stream)c) Heart contracts at angles to get maximum blood pressure and volume from itd) Intercalated disks- in between heart cells are gap junctions (Calcium channel) – allow a wave of contraction because they can stimulate each other by transmitting the single over the gap junctions (single-unit smooth muscle contraction) – act synchronized, not independent, rapid depolarization2. electrical activity deals with difference in rhythms (panic of this happens in a heart attack)3. angina- referred pain from the heart in which a person will not recognize a heart attack up to 42 hoursa) confused with indigestionF. Electric Impulse of heart= volume/minute1. Sino-atrial node-a) Located in Right Atrial wall, pacemaker of the heartb) Pace set by this node-- Average 100 BPM- under autonomic control (important for determining disrythmias)c) Normal resting heartrate is between 60 and 99 BPM- under parasympathetic control - exercising causes higher output pushes to an age-dependent heart rate max (sympathetic control)2. BPM under 60 can causes bradycardia, which is a problem and will cause cots, or there is athletic bradycardia, where a heart rate this low is okay3. Tachycardia- heart is working too hard, BPM is between 100 and 250 BPM just sitting there, this is a problem, usually happens with bad blood flow, sickle cell anemia, etc. it is usually a problem outside of the heart that causes problems in the heart4. Coronary arterial disease- injury to the coronary artery related to nutrition (from atherosclerosis- fat build up on arteries)5. When SA node is working, and the heart is healthy, we should expect to see all rhythms6. AV node- back up node not innervated by the nervous system (naturally 60 BPM- not all rhythms may be seen when present- missing events of the atrium)7. ventricular foci- 3rd back up plan– seen at between 40-20 BPM – barely survive on this plan, abnormal, and blood clotting happensa) Do not have all the rhythmsb) Come from the perkinje fibersc) Can see this occurringMake premature ventricular contractions (PVC) – dangerous because it says that the ventricle decided to beat on its own, and discoordinates the heart contractiond) 3 PVC in a row or 6 PVC in one minute isn’t good8. Panic mode= fibrillation- rate of 350 BPM – blood doesn’t go anywhere- failed pump, acute cardiac failureG. Cardiac physiology1. work= systole- contraction2. rest = diastolea) Atria and ventricles work and rest at different times3. stroke volume- volume that gets ejected during ventricular systole – when myosin is power-stroking4. ECG (EKG)- electrical activity moving through the system, not the actual event, but we associate the actual event with the actual eventa) P wave- atrial contraction- stimulated by the SA node onlyb) P-R interval- Atrial diastole—is the time of AV node is beginning to send its signal, allows the cuspid valves to close(1) Cannot be too short or too long, P-R is always between 0.12 and 0.2 seconds, or if it is less than this, it is called a first degree blockc) QRS complex- power stroke, ventricle contraction (causes stroke volume)(1) Q to R is when the signal is relayed down bundle branches, if we see multiple lines from Q to R, this says that left and right bundle branches are not coordinated, known as bundle branch blocks, this interferes with outputd) ST segment- very important, can not be too slow in getting to its mark – when heart gets blood, wild in heart attacks(1) If takes too much time, there is ST depression- which is signature indicator of the coronary arterial disease(2) ST elevation is resistance to blood flow, seen in heart attacks, and when seen at rest, known as hypertension in the hearte) Q-T segment is the entire contraction of the ventricle, and produces stroke volume, it lasts for 0.44 seconds of the 0.7 seconds in the whole cycle(1) QT segment- different than other muscles – has a plateauf) T- wave- repolarization, beginning of rest(1) Inverted T-waves indicates post-myocardial infarction, or an elongated Q wavesg) common diastole- is when ventricle is resting, and the whole heart rests and is the longest period in the whole cycle- blood is also flooding into the heart at this pointh) Top off the ventricles with atrial systole and restart the whole cycle(1) will suspect that they have hypertension5. Calcium induced calcium release- increase calcium concentration increases contractility, allows us to hold the depolarization and causes the contraction to last longer (calcium plateau- unique to cardiac muscle)a) Heart can adjust calcium movement – alters cardiac contractility(1) increase Ca creates increased contractilityb) calcium channel blockers – used to stop channel from opening and the amount of force in QT segment is not excessive- do not want the heart to contract as muchc) beta blocker – receptors for adrenaline or norepinephrine- are signals that run through the beta adrenergic receptors, which is another way to open the calcium channels, so we block themH. Blood flow- dependent on pressure gradient1. Right atrium  tricuspid valve  Right ventricle  pulmonary semilunar valve  pulmonary artery  lungs  capillaries (exchange – he calls ‘the beach’)  pulmonary veins  Left atrium  bicuspid valve  left ventricle (maximum pressure) aortic valve aorta  after-load pressure in arteries, must get past to get to body/ systemic circuitLecture 18 Outline of Last Lecture I. Cardiovascular system- Rate, Rhythm and Volume A. Rate + Rhythm = OutputB. NutritionC. Cardiovascular system D. Cardiac Anatomy Outline of Current Lecture E. Histology of Cardiac MuscleF. Electrical impulses of the HeartG. Cardiac PhysiologyH. Blood FlowCurrent LectureE. Histology of Cardiac muscle1. striated- has a sarcomere like in skeletal