LAST FINAL EVER (NU 665D Exam
III)/232 Q’s and A’s
P Wave - -Atrial depolarization
- P-R Interval - -0.12-0.20 seconds
- QRS Complex - -Ventricular Depolarization
0.06-0.10 (up to 0.12) seconds
- ST Segment - -Beginning of repolarization; should be isoelectric
- T Wave - -End of ventricular depolarization
- QT Interval - -Ventricular repolarization
Men <0.44 seconds
Women < (or = to) 0.46 seconds
- Depolarization - -Wave of positively charged sodium ions passing through
the myocardium
- Repolarization - -Returning to a polarized state
Occurs by potassium ions leaving the cells
- Electricity of heart - -In RA starting at SA node, moving through heart,
slowing (d/t Ca++ ions), pass thru AV node
Conducts rapidly (Na+ ions), through the bundle of His, down through right
and left bundle branches
- Atrial Fibrillation - -Irregularly irregular rhythm
-Absence of discernible P wave
-Atrial disorganization
- Paroxysmal A. Fib - --Recurrent
>1 episode lasting 30 or more seconds in duration
AF that terminates spontaneously within 7 days
- Persistent A. Fib - -Sustained A. Fib >7 days OR
Lasts <7 days but requires cardioversion
- Permanent A. Fib - -Refractory to cardioversion or accepted as a final
rhythm
- Acute A. Fib - -New onset OR first episode of A. Fib
, - Lone A. Fib - -patients <60yo without evidence of cardiac, pulmonary or
circulatory disease
- A. Fib Associated Cardiac Conditions - --HTN
-CHF
-CAD
-Rheumatic valvular disease
-Atrial and ventricular dilation or hypertrophy
-Congential heart disease
- A. Fib Associated Non-Cardiac Conditions - --Thyroid disease
-ETOH and caffeine abuse
-Pulmonary HTN
-COPD, OSA
-Infections
-Family/genetics (rare cases)
- Clinical Presentation of A.Fib - --Palpitations, tachycardia
-Fatgiue
-Chest pain
-Dizziness
-Syncope/Pre-syncope
-Sxs associated w/stroke (occult A. Fib)
-12-20% pf pts may be asymptomatic (often discovered by PCP during
routine visit)
-Note: Irregular pulse does not always indicate A. Fib; PACs, PVCs, A. Tach;
confirm rhythm w/EKG
- A.Fib Patient Evaluation - --PE: Heart sounds
-EKG- LA dilation?
-TFTs: should be done during initial discovery/change in condition (e.g.
difficult to control rate)
-Electrolytes with Magnesium
-BUN/Creatinine (helpful when trying to decide if AAD or OAC)
-Echocardiogram: valvular disease or reduced LVEF
-Ambulatory monitoring: Holter
- Stoke Risk in A. Fib - -Thromboembolism: primary morbidity assoc. w/
A.Fib. Thrombus formation and dislodgement from left atrial appendage
(LAA)
-Based on clinical risk factors and NOT on freq/duration of A.Fib
-Non-valvular meaning A. Fib presumably not r/t mitral valve heart disease,
specifically mitral stenosis
-In general ~48hrs for clot formation; if duration known to be <48hrs, can
cardiovert w/o AC
,-Second option: transesophageal echo to confirm absence of LAA thrombus
-Risk of thrombus is increased in first 3-4 weeks after DCCV, when gradual
return of atrial mechanical function can result in high risk for thrombus
- CHADS 2 - -CHF (1)
HTN (1)
Age >75 (1)
DM (1)
Prior Stroke (2)
- CHADS 2 VASc 2 - -CHF (1)
HTN (1)
Age >75 (2)
DM (1)
Prior Stroke (2)
Vascular disease (1)
Age 65-74 (1)
Female (1)
If score >2, oral anticoagulants (or if non valvular A. Fib for prior stoke, TIA)
If pt has nonvalvular A. Fib and CHADS2VASc2 score of 0, reasonable to omit
anticoag therapy
- New Anticoagulants - --3 currently approved
-Tested against coumadin
-No sign. diff b/w the three of them except for S/Es
-Avoid potent Pgp inducers (rifampin, carbemazepine, phehytoin, phenobarb,
St. John's wort) as will decrease effect
-Riva and Apixa: Avoid potent inhibitors of CYP3A4 and Pgp (Azoles, Protease
inhibitors, mycins), as will INCREASE AC effect
- Eliquis (apixaban) - -Dose: 5mg BID
Renal adjustment: 2.5mg twice daily, must have 2 or more of the following:
Age >80yo, Body wt </= 60kg, Serum creatinine >/= 1.5mg/dL
Half life: 12 hours
Time to Peak: 3-4hours
Direct factor Xa inhibitor
- Xarelto (rivaroxaban) - -Dose: 20mg daily w/evening meal of at least 500
calories for absorption
Renal Adjustment: CrCl 15-50mg once daily w/evening meal; CrCl
<15mL/min: avoid use
Half life: 5-13 hours
Peak: 2-4 hours
Director Factor Xa inhibitor
- Pradaxa (dabigatran) - -Dose: 150mg BID
, Renal adjustment: 75mg BID; not adequately studied
>10% pts have GI distress
Half life: 12-17hours, Up to 28hours w/renal impairment
Peak: 1-2hours
Direct thrombin inhibitor
- Coumadin - --Obtain baseline PT/INR and investigate if abnormal
-Determine use of potential warfarin interactions (meds)
-Document target INR and RX warfarin tablet strength
-Provide pt edu on safety, monitoring, food and drug interactions
-Recommend 1st INR check on day 3-4
- Coumadin Initiation - -Day 1-3, initial dose: 5mg (10mg)
Day 3-4:
-1.0-1.3 Dose 7.5mg
-1.4-1.5 Dose 5mg
-1.6-1.8 Dose 5/2.5mg alternating dose
->1.0 Dose 2.5mg
->2.0 hold x1 day, then 2.5mg
Reversal agents: Vitamin K 1-10mg IV/PO (not SQ/IM); Takes 6 (IV) to 25 (PO)
hours to reverse warfarin
- Treatment Approach for A.Fib - -3 Elements:
1) Rate control
2) Restoration and maintenance of sinus rhythm (if indicated)
3) Stroke prevention
-Goal is to alleviate sxs and improve QOL
- Rhythm Control - -Focus on restoration of sinus rhythm:
-Palpitations
-SOB
-Dizziness/Lightheadedness
-Activity intolerance
Prevention of tachycardia-induced cardiomyopathy
Prevention of hemodynamic compromise r/t A.Fib
- Rhythm Control Treatment - -Specific tx type depends on several factors:
-Heart disease w/LVH or depressed LVEF
-HF
-Age
-Underlying sinus node dysfunction
-Other arrhythmias (e.g. a. flutter)
-Underlying QT prolongation
-Renal function
Note: pts w/a CHADS2VASc2 score of zero who opt for a rhythm control
strategy may be considered to stop OAC
III)/232 Q’s and A’s
P Wave - -Atrial depolarization
- P-R Interval - -0.12-0.20 seconds
- QRS Complex - -Ventricular Depolarization
0.06-0.10 (up to 0.12) seconds
- ST Segment - -Beginning of repolarization; should be isoelectric
- T Wave - -End of ventricular depolarization
- QT Interval - -Ventricular repolarization
Men <0.44 seconds
Women < (or = to) 0.46 seconds
- Depolarization - -Wave of positively charged sodium ions passing through
the myocardium
- Repolarization - -Returning to a polarized state
Occurs by potassium ions leaving the cells
- Electricity of heart - -In RA starting at SA node, moving through heart,
slowing (d/t Ca++ ions), pass thru AV node
Conducts rapidly (Na+ ions), through the bundle of His, down through right
and left bundle branches
- Atrial Fibrillation - -Irregularly irregular rhythm
-Absence of discernible P wave
-Atrial disorganization
- Paroxysmal A. Fib - --Recurrent
>1 episode lasting 30 or more seconds in duration
AF that terminates spontaneously within 7 days
- Persistent A. Fib - -Sustained A. Fib >7 days OR
Lasts <7 days but requires cardioversion
- Permanent A. Fib - -Refractory to cardioversion or accepted as a final
rhythm
- Acute A. Fib - -New onset OR first episode of A. Fib
, - Lone A. Fib - -patients <60yo without evidence of cardiac, pulmonary or
circulatory disease
- A. Fib Associated Cardiac Conditions - --HTN
-CHF
-CAD
-Rheumatic valvular disease
-Atrial and ventricular dilation or hypertrophy
-Congential heart disease
- A. Fib Associated Non-Cardiac Conditions - --Thyroid disease
-ETOH and caffeine abuse
-Pulmonary HTN
-COPD, OSA
-Infections
-Family/genetics (rare cases)
- Clinical Presentation of A.Fib - --Palpitations, tachycardia
-Fatgiue
-Chest pain
-Dizziness
-Syncope/Pre-syncope
-Sxs associated w/stroke (occult A. Fib)
-12-20% pf pts may be asymptomatic (often discovered by PCP during
routine visit)
-Note: Irregular pulse does not always indicate A. Fib; PACs, PVCs, A. Tach;
confirm rhythm w/EKG
- A.Fib Patient Evaluation - --PE: Heart sounds
-EKG- LA dilation?
-TFTs: should be done during initial discovery/change in condition (e.g.
difficult to control rate)
-Electrolytes with Magnesium
-BUN/Creatinine (helpful when trying to decide if AAD or OAC)
-Echocardiogram: valvular disease or reduced LVEF
-Ambulatory monitoring: Holter
- Stoke Risk in A. Fib - -Thromboembolism: primary morbidity assoc. w/
A.Fib. Thrombus formation and dislodgement from left atrial appendage
(LAA)
-Based on clinical risk factors and NOT on freq/duration of A.Fib
-Non-valvular meaning A. Fib presumably not r/t mitral valve heart disease,
specifically mitral stenosis
-In general ~48hrs for clot formation; if duration known to be <48hrs, can
cardiovert w/o AC
,-Second option: transesophageal echo to confirm absence of LAA thrombus
-Risk of thrombus is increased in first 3-4 weeks after DCCV, when gradual
return of atrial mechanical function can result in high risk for thrombus
- CHADS 2 - -CHF (1)
HTN (1)
Age >75 (1)
DM (1)
Prior Stroke (2)
- CHADS 2 VASc 2 - -CHF (1)
HTN (1)
Age >75 (2)
DM (1)
Prior Stroke (2)
Vascular disease (1)
Age 65-74 (1)
Female (1)
If score >2, oral anticoagulants (or if non valvular A. Fib for prior stoke, TIA)
If pt has nonvalvular A. Fib and CHADS2VASc2 score of 0, reasonable to omit
anticoag therapy
- New Anticoagulants - --3 currently approved
-Tested against coumadin
-No sign. diff b/w the three of them except for S/Es
-Avoid potent Pgp inducers (rifampin, carbemazepine, phehytoin, phenobarb,
St. John's wort) as will decrease effect
-Riva and Apixa: Avoid potent inhibitors of CYP3A4 and Pgp (Azoles, Protease
inhibitors, mycins), as will INCREASE AC effect
- Eliquis (apixaban) - -Dose: 5mg BID
Renal adjustment: 2.5mg twice daily, must have 2 or more of the following:
Age >80yo, Body wt </= 60kg, Serum creatinine >/= 1.5mg/dL
Half life: 12 hours
Time to Peak: 3-4hours
Direct factor Xa inhibitor
- Xarelto (rivaroxaban) - -Dose: 20mg daily w/evening meal of at least 500
calories for absorption
Renal Adjustment: CrCl 15-50mg once daily w/evening meal; CrCl
<15mL/min: avoid use
Half life: 5-13 hours
Peak: 2-4 hours
Director Factor Xa inhibitor
- Pradaxa (dabigatran) - -Dose: 150mg BID
, Renal adjustment: 75mg BID; not adequately studied
>10% pts have GI distress
Half life: 12-17hours, Up to 28hours w/renal impairment
Peak: 1-2hours
Direct thrombin inhibitor
- Coumadin - --Obtain baseline PT/INR and investigate if abnormal
-Determine use of potential warfarin interactions (meds)
-Document target INR and RX warfarin tablet strength
-Provide pt edu on safety, monitoring, food and drug interactions
-Recommend 1st INR check on day 3-4
- Coumadin Initiation - -Day 1-3, initial dose: 5mg (10mg)
Day 3-4:
-1.0-1.3 Dose 7.5mg
-1.4-1.5 Dose 5mg
-1.6-1.8 Dose 5/2.5mg alternating dose
->1.0 Dose 2.5mg
->2.0 hold x1 day, then 2.5mg
Reversal agents: Vitamin K 1-10mg IV/PO (not SQ/IM); Takes 6 (IV) to 25 (PO)
hours to reverse warfarin
- Treatment Approach for A.Fib - -3 Elements:
1) Rate control
2) Restoration and maintenance of sinus rhythm (if indicated)
3) Stroke prevention
-Goal is to alleviate sxs and improve QOL
- Rhythm Control - -Focus on restoration of sinus rhythm:
-Palpitations
-SOB
-Dizziness/Lightheadedness
-Activity intolerance
Prevention of tachycardia-induced cardiomyopathy
Prevention of hemodynamic compromise r/t A.Fib
- Rhythm Control Treatment - -Specific tx type depends on several factors:
-Heart disease w/LVH or depressed LVEF
-HF
-Age
-Underlying sinus node dysfunction
-Other arrhythmias (e.g. a. flutter)
-Underlying QT prolongation
-Renal function
Note: pts w/a CHADS2VASc2 score of zero who opt for a rhythm control
strategy may be considered to stop OAC
