* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download 7 - ISpatula
Management of acute coronary syndrome wikipedia , lookup
Coronary artery disease wikipedia , lookup
Heart failure wikipedia , lookup
Cardiac surgery wikipedia , lookup
Cardiac contractility modulation wikipedia , lookup
Lutembacher's syndrome wikipedia , lookup
Myocardial infarction wikipedia , lookup
Hypertrophic cardiomyopathy wikipedia , lookup
Mitral insufficiency wikipedia , lookup
Electrocardiography wikipedia , lookup
Jatene procedure wikipedia , lookup
Quantium Medical Cardiac Output wikipedia , lookup
Heart arrhythmia wikipedia , lookup
Atrial fibrillation wikipedia , lookup
Ventricular fibrillation wikipedia , lookup
Arrhythmogenic right ventricular dysplasia wikipedia , lookup
Cardiovascular system- L3 Faisal I. Mohammed, MD, PhD Yanal A. Shafagoj MD, PhD University of Jordan 1 Electrical Activity of the Heart Different Expression levels and Different types of ion channels University of Jordan 2 Electrocardiogram ECG or EKG Composite record of action potentials produced by all the heart muscle fibers Compare tracings from different leads with one another and with normal records 3 recognizable waves P, QRS, and T University of Jordan 3 The Electrocardiogram The major deflections and intervals in a normal ECG include: P wave - atrial depolarization P-Q interval - time it takes for the atrial kick to fill the ventricles QRS wave - ventricular depolarization and atrial repolarization S-T segment - time it takes to empty the ventricles before they repolarize (the T wave) Correlation of ECG Waves and Systole 1. 2. 3. 4. 5. 6. Systole means ventricular contraction and diastole means ventricular relaxation. Cardiac cycle events are: Cardiac action potential arises in the SA node → P wave Atrial systole (Atrial contraction) Action potential enters AV bundle and leaves to the ventricles → QRS complex which masks atrial repolarization (un-recordable) Contraction of ventricles (systole) Begins shortly after QRS complex appears and continues during S-T segment Repolarization of ventricular fibers → T wave Ventricular relaxation/ diastole University of Jordan 5 Cardiac Cycle All events associated with one heartbeat Systole and diastole of atria and ventricles In each cycle, atria and ventricles alternately contract and relax During atrial systole, ventricles are relaxed During ventricle systole, atria are relaxed Forces blood from higher pressure to lower pressure During relaxation period, both atria and ventricles are relaxed The faster the heart beats, the shorter the relaxation period Systole and diastole lengths shorten slightly University of Jordan 6 Cardiac Cycle 7 Cardiac cycle refers to all events associated with blood flow through the heart Systole – contraction of heart ventricles Diastole – relaxation of heartventricles Cardiac Cycle Ventricular systole 0.3 second Ventricular diastole 0.5 seconds 8 Isovolumic contraction phase Rapid ejection period Slow ejection period Isovolumic contraction phase Rapid filling phase Slow filling (Diastasis) Atrial contraction phase Phases of the Cardiac Cycle 9 R T P (a) ECG 1 4 8 Q Atrial depolarization 2 Begin atrial systole 3 End (ventricular) diastolic volume 4 Ventricular depolarization 5 Isovolumetric contraction 6 Begin ventricular ejection 7 End (ventricular) systolic volume 8 Begin ventricular repolarization 9 Isovolumetric relaxation S 0.1 sec Atrial systole 0.3 sec Ventricular systole 120 0.4 sec Relaxation period 9 Dicrotic wave 100 Aortic pressure 5 80 6 (b) Pressure (mmHg) 1 Left ventricular pressure 60 40 Left atrial pressure 10 20 2 0 (c) Heart sounds S1 S2 S3 S4 3 End (ventricular) diastolic volume 130 10 Ventricular filling Stroke volume (d) Volume in ventricle (mL) 60 7 0 (e) Phases of the cardiac cycle Atrial contraction Isovolumetric contraction UniversityIsovolumetric of Jordan Ventricular ejection relaxation Ventricular filling Atrial contraction 10 11 Stroke Volume 12 SV = end diastolic volume (EDV) minus end systolic volume (ESV) EDV = amount of blood collected in a ventricle at the end of diastolic phase ESV = amount of blood remaining in a ventricle after contraction Cardiac cycle …cont 13 End diastolic volume (EDV) – End systolic volume (ESV) = Stroke volume (SV) SV X heart rate (HR) = cardiac output (CO) Ejection fraction = SV/EDV Autonomic control of cardiac cycle (pump) The EDV equals 110-120 ml and SV equals 70 ml. Therefore the ejection fraction is 65% Cardiac Output CO = volume of blood ejected from left (or right) ventricle into aorta (or pulmonary trunk) each minute CO = stroke volume (SV) x heart rate (HR) In typical resting male 5.25L/min = 70mL/beat x 75 beats/min Entire blood volume flows through pulmonary and systemic circuits each minute University of Jordan 14 Thank You 15