ECG Flashcards
Where is ectopic foci that induces atrial fibrillation?
ectopic foci in the pulmonary vein ostia
How changes refractory period and conductivity due to electrical remodeling induced by atrial fibrillation?
Shortened refractory period and increased conductivity
Effects of shortened refractory period and increased conductivity in atrial fibrillation?
creation and persistence of multiple ectopic foci and reentrant impulses within atria
The most common tachyarrhytmia?
atrial fibrillation
What illnesses precipitate atrial fibrillation?
Systemic ilnesses such: long-standing HTN, HF, hyperthyroidism.
Increased sympathetic tone
What is holiday heart syndrome?
Atrial fibrillation seen in patients after excessive alcohol consumption
atrial fibrillation treatment in symptomatic patients?
catheter ablation of pulmonary vein trigger sites
Atrial fibrillation ecg? P, regularity R-R, QRS?
P - truly absent, because absent organized depolarization
Irregularly-irregular R-R intervals
Narrow QRS
normal QRS duration?
<0,12s (3 mazi langeliai)
Normal PR interval duration?
0,12-0,20s (5 mazi langeliai)
WPW. What is accessory pathway?
Accessory bypass tract=bundle of Kent
What connects bundle of Kent?
Directly connects the atria to the ventricles and allows electrical impulses to bypass the AV node
Young patient has repeated episodes of palpitations. What suspect?
PSVT –> suspect WPW
What causes electrical impulses that goes through the bundle of Kent?
preexcitation of the ventricles
What changes creates the preexcitation of the ventricles in WPW?
characteristic triad on ECG
Triad of WPW?
Delta wave; Shortened PR interval (<0,12s) (normal PR 0,12-0,22s) Wide QRS (>0,12s)
WPW asymptomatic. ECG? How is it called?
Many WPW patients asymptomatic and only WPW pattern (triad) is seen on ECG.
It is called Ventricular preexcitation.
Impulse just go through the bundle of Kent.
Name: ventricular preexitation
ECG: WPW pattern
WPW symptomatic. ECG? How is it called?
Symptomatic can be if WPW pattern + symptomatic arrythmia. ECG: AVRT
It is called WPW syndrome. AVRT is the most common arrythmia that occurs with WPW.
Reentrant circle via bundle of Kent.
Name: WPW syndrome
ECG: reentrant tachycardia (AVRT)
WPW pattern. Symptomatic or asymptomatic?
Asymptomatic
WPW syndrome. Symptomatic or asymptomatic?
symptomatic
Symptoms if arrythmia occurs in WPW?
Intermitent palpitations, sensation of racing heart, lightheadness or syncope.
Atrial fibrillation. What is ventricular response? What is average ventricular rate? regularity?
Depends on the transmission via AV node. Once AV is excited, it enters refractory period, so additional impulses cannot be transmited to the ventricles despite there is excitation of atria. Ventricular rate: 90-170k/min. Irregular, because atrial excitation is chaotic.
3 factors for thrombus formation in atrial fibrillation?
Left atrial enlargement.
Blood stasis due to ineffective atrial contraction;
Atrial inflammation and fibrosis (exerts a procoagulant effect).
Which part of the heart is the most susceptible for thrombus formation in Afib?
Left atrial appendage.
Afib. There is a thrombus. Where can it embolize?
Stroke, acute limb ischemia, acute mesenteric ischemia
If thrombus in Afib forms in right heart. In which part and where can embolize?
forms in right atrial appendage; Embolize to pulmonary circulation.
In what 2 cases can thrombus develop in LV?
In case of LV aneurysm (eg post-MI) and severe LV systolic dysfunction. NOT ASSOCIATED WITH Afib.
What is the backgroud to develop for thrombus in case patients has prostetic valves?
lack of adequate anticoagulation.
How often thrombus form in pulmonary veins or sinus.of valsalva (aortic sinus)?
Rarely and they are not assoc. with Afib.
What is crista terminalis?
thick band of atrial muscle that separates smooth sinus venosus from the right atrial appendage and atrium proper.
What originates from crista terminalis?
crista terminalis is the sito of origin of the atrial pectinate muscles.
Duration of paroxysmal afib?
resolving spontaneously within 7 days
Duration of persistent afib?
lasting > 7 days.
What primarily drives development of afib?
structural and electrical remodeling.
What are structural remodeling causes for afib?
comorbidities that lead to atrial stretching and dilation: hypertension, HF, mitral valve disease. Physiologic age-related atrial dilation. CAD and its assoc factor (DM, smoking), may induce structucal changes due to ischemia –> ventricular dysfunction –> consequent atrial dilation.
What are electrical remodeling causes for afib?
Age related changes; Previous exposure to afib. electrical foci (in pulmonary vein ostia) Alcohol intake and increased SNS activity may contribute