Search Results

Causes of Angina

By: Administrator, Views: 11138

Angina is a type of chest pain caused by reduced blood flow to the heart. Angina (an-JIE-nuh or AN-juh-nuh) is a symptom of coronary artery disease. Angina, which may also be called angina pectoris, is often described as squeezing, pressure, heaviness, tightness or pain in your chest.

Electrical changes in the heart

By: HWC, Views: 7562

• ECG: Graph of the voltage changes that occur during the cardiac cycle. • Readings are taken by electrodes placed on the surface of the body. • Electrodes detect voltage changes caused by the electrical activity of the heart. • P wave = atrial excitation (atrial depolarization). ...

Automated external defibrillator (AED)

By: Administrator, Views: 10785

An automated external defibrillator (AED) is a portable electronic device that automatically diagnoses the life-threatening cardiac arrhythmias of ventricular fibrillation and pulseless ventricular tachycardia, and is able to treat them through defibrillation, the application of electricity which...

Blood Pressure Measurement

By: Administrator, Views: 10650

How nurses check a patient's blood pressure. Blood Pressure The pressure exerted by the blood on the walls of the arteries. Higher (systolic) number: the pressure while the heart contracts. Lower (diastolic) number: the pressure when the heart relaxes between beats. Measured by a sphygmoma...

Congenital Heart Defects Animation

By: Administrator, Views: 10902

Pulse, blood pressure, and respiration vary according to the child’s age. A newborn’s pulse rate is irregular and rapid, varying from 120 to 140 beats per minute. Blood pressure is low and can vary with the size of the cuff used. Average blood pressure at birth is 80/46. Respirations are ...

Depolarization of the SA node, Action potentials of the myocardium & ANS effects

By: HWC, Views: 7626

• A typical contractile cell in the myocardium has a resting membrane potential. • The resting membrane potential of cells in the SA node is not fixed, and is known as the pacemaker potential. • The action potential of a healthy SA nodal cell has three parts: • Pacemaker potential: ...

Baroreceptor Reflex

By: HWC, Views: 7067

Baroreceptors located In the carotid sinus and the arch of the aorta respond to increases in blood pressure. Increased blood pressure stretches the carotid arteries and aorta causing the baroreceptors to increase their basal rate of action potential generation. Action potentials are conduct...

Blood Flow through the Human Heart

By: HWC, Views: 7487

The heart is the pump of the human circulatory system. The left side of the heart has two connected chambers, the left atrium and the left ventricle. The right side of the heart also has two connected chambers, the right atrium and the right ventricle. These two sides, or pumps, of the heart are ...

Epinephrine/NE (heart rate, altered blood flow, glycogenolysis & bronchodilation)

By: HWC, Views: 7652

• Stressors trigger increased sympathetic stimulation from the hypothalamus to the chromaffin cells of the adrenal medulla. • This causes the immediate release of epinephrine and norepinephrine (NE). • Epinephrine/NE binds to the cardiac muscles of the heart. • Cardiac muscle cells ...