CVD II - HF and Valv HD Flashcards
(94 cards)
what are the functions of the SA node
- primary pacemaker
- regulates atrial function
- produces P wave - atrial depolarization
what is the function of the AV node
- regulates atrial impulses entering ventricles
- slows conduction rate of SA generated impulses
what is happening during the QRS complex
simulataneous depolarization of the ventricles
what happens during the T wave
repolarization of the ventricles
disruption of the electrical impulse generation or conduction in the heart leads to what abnormal cardiac functions
- formation of abnormal impulse
- increased impulse formation
- enhanced or abnormal impulse formation
- delayed depolarization
- re-excitation of the heart after refractory period
disruption of the electrical impulse generation or conduction in the head may be due to an area of:
- infarction
- ischemia
- electrolyte imbalance
- medication
the most common cause of sudden cardiac death is:
ventricular fibrillation
what are the causes of arrhythmias
- cardiovascular disorders
- pulmonary disorder
- autonomic disorder
- hyperthyroidism
- drugs
- electrolyte imbalance
- anxiety and anger
what cardiovascular disorders cause arrhythmias
- MI
- mitral stenosis
- valvular disease
- ischemic heart disease
- congestive heart failure
what pulmonary disorders cause arrhythmias
-pneumonia
- obstructive lung disease
what drugs cause arrhythmias
- epinephrine
- alcohol
- digitalis
- morphine
- beta blockers
- tricyclic antidepressants
what are the supraventricular arrhythmias
- sinus nodal disturbances: sinus arrhythmias, sinus tachycardia, sinus bradycardia
- disturbances of atrial rhythm: premature atrial complexes, atrial flutter
- ventricular tachycardia
- ventricular fibrillation
what qualifies bradycardia
less than 60 beats/min
what qualifies tachycardia
greater than 100 bpm
what are the symptoms of arrhythmias
- palpitations, fatigue
- dizziness, syncope, angina
- CHF
- SOB
- orthopnea
- peripheral edema
describe atrial fibrillation
- most common arrhythmia
- rapid uncontrolled atrial activity
- irregularly irregular rhythm
- risk of arterial clot formation: embolism and stroke
what is a heart block
- impulse is partially or completely blocked
- prolonged or no conduction
what are the degrees of heart block and describe each
- first degree: longer conduction time
- second degree: Mobitz I: more prolonged and no P wave. Mobitz II: repetitive or occasional sudden blocks without previous prolonged conduction time
- third degree: no impulses- complete block. indication for pacemaker
describe ventricular arrhythmias
- premature ventricular complexes (PVCs)
- common
- abnormal QRS complex + pause
- increased risk of death if patients have underlying CVD ( heart failure, MI, valvular heart disease)
describe ventricular tachycardia
- if more than 3 consecutive PVS at 100 bpm
- if lasts for more than 30 seconds, requires termination
- torsades de pointes- potentially life threatening
describe ventricular flutter and fibrillation
- lethal
- consequence of ischemic heart disease
- cardiac contraction is not sequential, chaotic
is there tx for arryhthmias
no just aimed at managing symptoms
what are the SE for sodium channel blockers
- bitter taste
- dry mouth
- oral ulcerations
what are the SE of beta blockers
taste changes, lichenoid reactions