Characteristics of left and right heart failureCharacteristics of left andright heart failureLeft HF:Right HF:Forward failureBackward failureReduced cardiacoutputReduced cardiac outputHypotensionHypotensionPulmonary edemaPeripheral edemaDyspneaHepatomegalyFatigueAscites
Characteristics of left and right heart failure Characteristics of left and right heart failure Left HF: Forward failure Right HF: Backward failure Reduced cardiac output Hypotension Pulmonary edema Dyspnea Fatigue Reduced cardiac output Hypotension Peripheral edema Hepatomegaly Ascites
Aconsiderable body of literature supportsabnormalities in myocardial excitation-contractioncoupling in CHF.An appreciation of the principlesinvolved in this cell signaling process is crucial tounderstand current and future pharmacotherapiesfor CHF.A brief overview of myocardialexcitation-contraction coupling will be provided
A considerable body of literature supports abnormalities in myocardial excitation–contraction coupling in CHF. An appreciation of the principles involved in this cell signaling process is crucial to understand current and future pharmacotherapies for CHF. A brief overview of myocardial excitation–contraction coupling will be provided
Physiology of muscle contractionA. Action potentialcardiac muscle cells are electrically excitable.However unlike the cells of othermusclesand nerves, the cells of cardiac muscle showa spontaneous, intrinsic rhythm generatedby specialized “pacemaker" cells located inthe sinoatrial (SA),and atrioventricular (AV)nodes.The cardiac cells also have anunusually long action potentialB.Cardiac contraction
Physiology of muscle contraction A. Action potential cardiac muscle cells are electrically excitable. However unlike the cells of other muscles and nerves, the cells of cardiac muscle show a spontaneous, intrinsic rhythm generated by specialized “pacemaker” cells located in the sinoatrial (SA), and atrioventricular (AV) nodes. The cardiac cells also have an unusually long action potential. B. Cardiac contraction
myocardial excitation-contraction couplingThe physiological processes that beginwithcardiac sarcolemma membrane depolarization andculminate in contraction are collectively defined asmyocardial excitation-contraction coupling
myocardial excitation–contraction coupling The physiological processes that begin with cardiac sarcolemma membrane depolarization and culminate in contraction are collectively defined as myocardial excitation–contraction coupling
Cardiac contractilityMyocardial contraction is the result ofcalcium entry through L-type channels, givingrise to an increase in cytosolic calciumThe calcium is derived from two sources:1.Extracellular calcium2. The sarcoplasmic reticulum andmitochondria
Cardiac contractility Myocardial contraction is the result of calcium entry through L-type channels, giving rise to an increase in cytosolic calcium The calcium is derived from two sources: 1. Extracellular calcium 2. The sarcoplasmic reticulum and mitochondria