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Cardiac Function (Cardiac Cycle (Each heartbeat is composed of a period of…

- - - - The rate of rise in pressure is an indication of the contractile state of the heart. The greater the change in pressure per unit time (dP/dt), the higher the contractile state
        
        blood ejected with each contraction of the ventricle is called the stroke volume (SV).
        
        1.SV= EDV -ESV.
        2.EF= SV / EDV .
  - - - The rate of ventricular relaxation is indicated by the drop in ventricular pressure per unit time and is called the −dP/dt.
  - - - diastolic blood pressure(Arterial pressures fall to their lowest value just before semilunar valve opening. )
- - - - (R) has two major determinants: (1) coronary artery diameter and (2) the varying degrees of external compression attributable to myocardial contraction and relaxation
      - P=ABP-RAP
      - 影響：(1) reduced driving pressure (e.g., low aortic blood pressure or high right atrial pressure), (2) reduced vessel diameter (e.g., myocardial hypertrophy, arteriosclerosis, thrombosis, vasoconstricting chemicals), (3) reduced perfusion time (e.g., high heart rates, some dysrhythmias), (4) increased metabolic demands (e.g., fever, sepsis, anemia).
- - - - Critical narrowing of the coronary lumen over time or sudden rupture of a plaque followed by thrombus formation causes the clinical syndromes of CHD
        
        The diagnosis of MI is based on three primary indicators: signs and symptoms, electrocardiographic changes, and elevations in the levels of specific marker proteins in the blood(CKMB、Tropornin I).
        
        治療：冠狀動脈阻塞的處理包括（A）用諸如血栓溶解之類的藥物進行溶栓；（B）經皮腔內冠狀動脈成形術破壞斑塊，隨後進行抗凝或支架置入；（C）放置支架以防止再閉塞（D）冠狀動脈旁路移植術–手術放置新導管以繞過動脈的閉塞區域
- - - - Diastolic Dysfunction ：removes free calcium ions from the cytoplasm by pumping them back into the sarcoplasmic reticulum and across the cell membrane into the extracellular fluid，calcium ions inhibits cross-bridge formation and allows the thick and thin filaments of the sarcomere to passively slide apart
      - 機制
        ：1.baroreceptor response→brain→SNS activation
        2.RAAS activation→↓GFR→kidney→fluid retention→preload
        3.↑Ventricular wall tension→Heart→myocyte growth→Hypertrophy
        
        Clinical Manifestations ：1.Left-Sided Heart Failure --Pulmonary congestion and edema 、Dyspnea
        2.Right-Sided Heart Failure --JVC↑、congestive splenomegaly、ascites
        
        Cardiogenic shock occurs primarily as a result of severe dysfunction of the left, right, or both ventricles that results in inadequate cardiac pumping.
        
        Clinical manifestations ：↑ heart rate and ↑vascular resistance, which maintain blood pressure even though cardiac output has decreased.
        
        治療：1.Drugs that block β1 receptors 、norepinephrine (NE) and angiotensin (Ang II)
        2.immune cytokines have been implicated in cardiac remodeling.
      - Systolic Dysfunction ：
        (ATP↓→ EF↓)