Cardiovascular Physiology

Erythrocytes

Leukocytes

Lymphocytes

Platelets

Blood Is Divided into Groups by Antigens Located on Erythrocytes

The Principal Types of Cardiac Action Potentials Are the Slow and Fast Types

Ionic Basis of the Resting Potential

The Fast Response Depends Mainly on Voltage-Dependent Sodium Channels

Ionic Basis of the Slow Response

Conduction of the Fast Response

Conduction of the Slow Response

Fast Response

Slow Response

Effects of Cycle Length

Sinoatrial Node

Ionic Basis of Automaticity

Overdrive Suppression

Atrial Conduction

Atrioventricular Conduction

Ventricular Conduction

Early Afterdepolarizations

Delayed Afterdepolarizations

Scalar Electrocardiography

Altered Sinoatrial Rhythms

Atrioventricular Transmission Blocks

Premature Depolarizations

Ectopic Tachycardias

Fibrillation

Excitation-Contraction Coupling Is Mediated by Calcium

Mechanics of Cardiac Muscle

Ventricular Systole

Echocardiography Reveals Movement of the Ventricular Walls and of the Valves

The Two Major Heart Sounds Are Produced Mainly by Closure of the Cardiac Valves

Passive or Diastolic Pressure-Volume Relationship

Active or End-Systolic Pressure-Volume Relationship

Pressure and Volume during the Cardiac Cycle: The P-V Loop

Preload and Afterload during the Cardiac Cycle

Contractility

Parasympathetic Pathways

Sympathetic Pathways

Higher Centers Also Influence Cardiac Performance

Heart Rate Can Be Regulated via the Baroreceptor Reflex

The Bainbridge Reflex and Atrial Receptors Regulate Heart Rate

Respiration Induces a Common Cardiac Dysrhythmia

Activation of the Chemoreceptor Reflex Affects Heart Rate

Ventricular Receptor Reflexes Play a Minor Role in the Regulation of Heart Rate

The Frank-Starling Mechanism Is an Important Regulator of Myocardial Contraction Force

Changes in Heart Rate Affect Contractile Force

Nervous Control

Cardiac Performance Is Also Regulated by Hormonal Substances

Resistances in Series and in Parallel

Mean Arterial Pressure

Cardiac Output

Peripheral Resistance

Pulse Pressure

Stroke Volume

Arterial Compliance

Total Peripheral Resistance and Arterial Diastolic Pressure

Arterioles Are the Stopcocks of the Circulation

Capillaries Permit the Exchange of Water, Solutes, and Gases

The Law of Laplace Explains How Capillaries Can Withstand High Intravascular Pressures

Diffusion Is the Most Important Means of Water and Solute Transfer Across the Endothelium

Diffusion of Lipid-Insoluble Molecules Is Restricted to the Pores

Lipid-Soluble Molecules Pass Directly Through the Lipid Membranes of the Endothelium and the Pores

Capillary Filtration Is Regulated by the Hydrostatic and Osmotic Forces Across the Endothelium

Balance of Hydrostatic and Osmotic Forces

The Capillary Filtration Coefficient Provides a Method to Estimate the Rate of Fluid Movement Across the Endothelium

Hypoxia-inducible factor(s) and angiogenesis

Pinocytosis Enables Large Molecules to Cross the Endothelium

Cytoplasmic Ca⁺⁺ Is Regulated to Control Contraction, via MLCK

Contraction Is Controlled by Excitation-Contraction Coupling and/or Pharmacomechanical Coupling

Control of Vascular Tone by Catecholamines

Control of Vascular Contraction by Other Hormones, Other Neurotransmitters, and Autocoids

Autoregulation and the Myogenic Mechanism Tend to Keep Blood Flow Constant

The Endothelium Actively Regulates Blood Flow

Tissue Metabolic Activity Is the Main Factor in the Local Regulation of Blood Flow

Impulses That Arise in the Medulla Descend in the Sympathetic Nerves to Increase Vascular Resistance

Sympathetic Nerves Regulate the Contractile State of the Resistance and Capacitance Vessels

The Parasympathetic Nervous System Innervates Blood Vessels Only in the Cranial and Sacral Regions of the Body

Epinephrine and Norepinephrine Are the Main Humoral Factors That Affect Vascular Resistance

The Vascular Reflexes Are Responsible for Rapid Adjustments of Blood Pressure

The Peripheral Chemoreceptors Are Stimulated by Decreases in Blood Oxygen Tension and pH and by Increases in Carbon Dioxide Tension

The Central Chemoreceptors Are Sensitive to Changes in Paco₂

Other Vascular Reflexes

Preload or Filling Pressure of the Heart

Cardiac Function Curve

Factors That Change the Cardiac Function Curve

Mathematical Analysis of the Vascular Function Curve

Venous Pressure Depends on Cardiac Output

Blood Volume

Venomotor Tone

Blood Reservoirs

Peripheral Resistance

Myocardial Contractility

Blood Volume

Peripheral Resistance

Gravity

Muscular Activity and Venous Valves

Respiratory Activity

Artificial Respiration

Physical Factors

Neural and Neurohumoral Factors

Metabolic Factors

Skin Blood Flow Is Regulated Mainly by the Sympathetic Nervous System

Ambient Temperature and Body Temperature Play Important Roles in the Regulation of Skin Blood Flow

Skin Color Depends on the Volume and Flow of Blood in the Skin and on the Amount of O₂ Bound to Hemoglobin

Regulation of Skeletal Muscle Circulation

Local Factors Predominate in the Regulation of Cerebral Blood Flow

Functional Anatomy

Pulmonary Hemodynamics

Regulation of the Pulmonary Circulation

Anatomy

Renal Hemodynamics

The Renal Circulation Is Regulated by Intrinsic Mechanisms

Intestinal Circulation

Hepatic Circulation

Changes in the Circulatory System at Birth

Mild to Moderate Exercise

Severe Exercise

Postexercise Recovery

Limits of Exercise Performance

Physical Training and Conditioning

Hemorrhage Evokes Compensatory and Decompensatory Effects on the Arterial Blood Pressure

The Compensatory Mechanisms Are Neural and Humoral

The Decompensatory Mechanisms Are Mainly Humoral, Cardiac, and Hematologic

The Positive and Negative Feedback Mechanisms Interact