LIST THE ELEMENTS OF THE INTRINSIC CONDUCTION SYSTEM IN ORDER, STARTING FROM THE SA NODE.
SA NODE -> ATRIOVENTRICULAR (AV) NODE -> ATRIOVENTRICULAR (AV) BUNDLE -> BUNDLE BRANCHES -> PURKINJE FIBERS
AT WHAT STRUCTURE IN THE TRANSMISSION SEQUENCE IS THE IMPULSE TEMPORARILY DELAYED? WHY?
ATRIOVENTRICULAR (AV) NODE; THIS DELAY IS IMPORTANT BECAUSE IT ENSURES THAT THE ATRIA HAVE EJECTED THEIR BLOOD INTO THE VENTRICLES FIRST BEFORE THE VENTRICLES CONTRACT.
EVEN THOUGH CARDIAC MUSCLE HAS AN INHERENT ABILITY TO BEAT, THE NODAL SYSTEM PLAYS A CRITICAL ROLE IN HEART PHYSIOLOGY. WHAT IS THAT ROLE?
GENERATE ACTION POTENTIALS AT A GREATER FREQUENCY THAN OTHER CARDIAC MUSCLE CELLS, THEY ARE THE PACEMAKER OF THE HEART. THEREFORE, IT SETS THE HEARTRATE UNDER NORMAL CIRCUMSTANCES
DEFINE ECG
THE GRAPHIC RECORDING OF THE ELECTRICAL CHANGES (DEPOLARIZATION FOLLOWED BY REPOLARIZATION) OCCURING DURING THE CARDIAC CYCLE.
DRAW AN ECG WAVE FORM REPRESENTING ONE HEARTBEAT. LABEL THE P, QRS, AND T WAVES; THE P-R INTERVAL; THE S-T SEGMENT, AND THE Q-T INTERVAL.
WHY DOES HEART RATE INCREASE DURING RUNNING?
IN GREATER DEMAND WHEN OUR BODY IS UNDER THAT KIND OF STRAIN. THE HEART MUST BEAT FASTER AND HARDER IN ORDER TO DELIVER THE LARGER AMOUNT OF BLOOD TO MUSCLES BEING USED WHEN RUNNING.
DESCRIBE WHAT HAPPENS IN THE CARDIAC CYCLE IN THE FOLLOWING SITUATIONS.
IMMEDIATELY BEFORE THE P WAVE
HEART IS IN DIASTOLE
DESCRIBE WHAT HAPPENS IN THE CARDIAC CYCLE IN THE FOLLOWING SITUATIONS.
DURING THE P WAVE
DEPOLARIZATION OF ATRIA
Ok, so you’re using my notecards which is great. I am glad I could help you out cause I wish I had someone to help me out when I took this course. I know Anatomy is super hard.
I only ask that if you find these notecards helpful, you join Easy Notecards and create at least one notecard set to help others out. It can be for any subject or class. Thanks and don’t forget to rate my helpfulness!
DESCRIBE WHAT HAPPENS IN THE CARDIAC CYCLE IN THE FOLLOWING SITUATIONS.
IMMEDIATELY AFTER THE P WAVE (P-R SEGMENT)
CONTRACTION OF ATRIA
DESCRIBE WHAT HAPPENS IN THE CARDIAC CYCLE IN THE FOLLOWING SITUATIONS.
DURING THE QRS WAVE
DEPOLARIZATION OF VENTRICLES
DESCRIBE WHAT HAPPENS IN THE CARDIAC CYCLE IN THE FOLLOWING SITUATIONS.
IMMEDIATELY AFTER THE QRS WAVE (S-T INTERVAL)
CONTRACTION OF VENTRICLES
DESCRIBE WHAT HAPPENS IN THE CARDIAC CYCLE IN THE FOLLOWING SITUATIONS.
DURING THE T WAVE
REPOLARIZATION OF VENTRICLES
TACHYCARDIA
A HEART RATE OVER 100 BEATS/MIN
BRADYCARDIA
A HEART RATE BELOW 60 BEATS/MIN
FIBRILLATION
RAPID, UNCOORDINATED HEART CONTRACTIONS THAT MAKES HEART USELESS AS A PUMP
WHICH WOULD BE MORE SERIOUS, ATRIAL OR VENTRICULAR FIBRILLATION? WHY?
VENTRICULAR FIBRILLATION, BECAUSE WHEN YOUR IN V-FIB YOUR PRETTY MUCH DEAD UNLESS THEY CAN SHOCK YOUR HEART BACK INTO RHYTHM. WITH ATRIAL FIBRILLATION, IT CAN BE TREATED WITH ANTI-RHYTHMIC DRUGS.
ABNORMALITIES OF HEART VALVES CAN BE DETECTED MORE ACCURATELY BY AUSCULTATION THAN BY ELECTROCARDIOGRAPHY. WHY IS THIS SO?
ABNORMAL HEART VALVES CAUSE EXTRA HEART SOUNDS (S3 AND S4) THAT CAN BE HEARD WITH A STETHOSCOPE. AN ECG JUST MEASURES ELECTRICAL ACTIVITY IN THE HEART, IT REALLY DOESNT HAVE ANYTHING TO DO WITH HOW THE VALVES WORK.