EKG
Can record electrical currents, this acronym is used to avoid confusion with an EEG, which measures neuron activity on the scalp. Electrodes for this are placed on limbs & chest, and each records slightly different activity
EKG (electrocardiogram)
Larger P wave
(0.1 sec), depolarization of SA node causes atria depolarization, atrial systole forces blood that has collected in atria through open AV valves into ventricles
Atrial systole
Athletes have stronger systole & can pump more blood with each contraction; all of this is known as ______
Increased stroke volume
Measure of pressure in arteries generated by left ventricle during systole & the remaining pressure in the vessel during diastole
Blood pressure
If conduction pathway is normal, if heart is enlarged, if heart regions are damaged, and cause of chest pain
What the EKG can show/determine
Indicates myocardial infarction
Larger Q wave
(0.3 sec), begins with contraction of ventricle walls, pressure rises so blood is forced against AV valves, causing them to shut
Ventricular systole
Organized into routes that carry blood to specific organs. A part of the cardiac output flows separately to each part of the body, and deoxygenated blood is returned to the heart in a separate set of veins
Blood vessels
Commonly called a blood pressure cuff, this measures blood pressure. The top number in the reading indicates the systolic pressure and the bottom indicates the diastolic pressure
Sphygmomanometer
Represents atrial depolarization as impulse spreads from sinoatrial node and through both atria
P wave
Indicates enlarged ventricles
Larger R wave
Pressure rises enough to force blood through both semi-lunar valves; total blood ejected is 70 mL
Ventricular ejection
Blood comes out of the heart from the left ventricle under great pressure, which can be felt as a _____ in several places throughout the body
Pulse
Walls aren't as muscular. They're made of thinner layers of tissue and are distensible so they can adapt to changes in blood pressure and volume
Venules and veins
Rapid ventricular depolarization, atrial repolarization is also occurring, but its electrical activity is masked by this
QRS complex
Indicates heart muscle isn't getting enough O2 (from blockage of coronary artery)
Flat T wave
Relaxation period (0.4 sec), both atria & ventricles relax. As pressure drops, blood from aorta & pulmonary trunk flows backwards but is stopped by cusps of closed semi-lunar valves. Pressure drops enough, AV valves open, blood collected during atrial diastole rushes into ventricles from atria. At the end, P wave appears, atria contract, cycle starts again
Diastole
Very elastic and expands as blood pressure increases when blood leaves the left ventricle
Arteries and arterioles
Leaky valves in veins cause them to become dilated and twisted, caused by congenital defects in valves, prolonged standing, pregnancy, aging, and obesity.
Varicose veins
Ventricular repolarization, just as ventricles start to relax (diastole)
T wave
Larger T wave
During exercise, as the heart beats faster, the relaxation period shortens, but the _____ doesn't change much
Systole timing
Muscular walls of arterioles allow them to play a role in _____. By contracting this muscular layer, less blood will flow through that vessel & increases the pressure of blood elsewhere in the body
Maintaining blood pressure
Compression/support socks or stockings, sclerotherapy (inserting highly concentrated saline solution into impacted vein), surgery (removal of or tying off of vein), and laser/light therapy
Treatments of varicose veins