Module 7.3 - Arrhythmia Management Flashcards
How should you approach diagnosing an arrhythmia?
- Every suspicion of arrhythmia should begin with a 12 lead EKG
- Complete history and physical – the patient may have an underlying heart disease as the etiology of the arrhythmia
- If the arrhythmias is paroxysmal, a 24 hour Holter monitor may be indicated
- Event monitor is another option. The patient can activate a recording if they experience symptoms. The data is relayed to their monitoring station.
- Implantable loop recorder – stores information that is retrieved or “interrogated” later in an office setting
- Basic lab should be evaluated to include electrolytes, renal function, thyroid studies and hemoglobin.
What is atrial fibrillation?
It is an atrial tachyarrhythmia characterized by chaotic activation of the atria with loss of atrial mechanical function. There is an absence of P waves on an EKG
How do you manage patients with atrial fibrillation?
1. Rate control
- Can be accomplished with the use of verapamil, diltiazem and/or digoxin.
- Nonpharmacological: AV nodal ablation in association with pacemaker placement. R**eserved for patients who have failed pharmacological rate control or if the effects of medication are uneffective or the medications are contraindicated.
2. Prevent thromboembolic events
- Anticoagulation can be obtained with warfarin (goal INR 2-3), dabigatran, rivaroxaban, apixaban or edoxaban.
- In patients with an enlarged left atrium on echocardiogram, there is an increased mortality and risk of stroke
- It is important to determine a patient’s risk for stroke when weighing the risk/benefit on anticoagulation.
- The CHADS2 scores combine risk factors to determine a score to guide decision making.
3. Rhythm control
- Amiodarone is the most effective antiarrhythmic agent for maintenance of NSR but has extensive toxicity to lungs, liver and thyroid.
- Pharmacological cardioversion with ibutilide may be attempted in a hospital setting. If sinus rhythm is achieved, antiarrhythmic agents such as flecainide, sotolol and propafenone can be started for maintenance.
How do you calculate a CHADS2 score and what is it used for?
- It is a scoring system used to estimate stroke risk in AF patients
- Consideration of oral anticoagulation prophylaxis is recommended for patients with a score of 1 and OAC use is a definite recommendation for patients with a score of 2 or greater and for those with a history of stroke or transient ischemic attack
How do you manage patients with atrial flutter?
Anticoagulation and rate control drugs as with atrial fibrillation (Warfarin & verapamil, diltiazem and/or digoxin). If highly symptomatic or if rate control is difficult, electrical or chemical cardioversion is appropriate. If the patient has a pacemaker in place, overdrive atrial pacing may be attempted
How do you treat patients with sinus tachycardia?
Therapy is aimed at treatment of the underlying cause. Assess volume status and electrolyte balance. Look for pain, fever, anemia, anxiety, CHF. If the patient remains symptomatic, beta blockers may be indicated.
How do you treat patients with AVNRT (SVT)?
- Pts w/ WPW syndrome are predisposed to this arrhythmia.
1. Acutely, Vagal maneuvers can be tried to convert to NSR although there may be no effect at all.
2. If unsuccessful, adenosine may be needed to break the tachycardia.
3. Medical therapy - beta blockers, calcium channel blockers and digoxin are used.
- If the patient experiences treatment failure with these, propafenone and flecainide can be tried.
4. Catheter ablation has a success rate of approximately 96% if the patient is a candidate.
What are some predisposing conditions for ventricular tachycardia?
CAD, MI, cardiomyopathy, CHF, hypoxemia, hypokalemia.
What is Nonsustained VT?
three or more consecutive ventricular complexes (> 100 bpm) that terminate spontaneously within 30 seconds
What is Sustained monomorphic VT?
tachycardia of ventricular origin with single QRS morphology that lasts more than 30 seconds or requires cardioversion for hemodynamic instability
What is Polymorphic VT?
It is an ever-changing QRS morphology. It is associated with hemodynamic collapse or instability
How do you treat ventricular tachycardia?
- Start CPR & attach monitor/defibrillator ASAP
- If Vfib/Vtach shock @ 360J
- Continue CPR for 2min
- If Vfib/Vtach Shock @ 360J
- Continue CPR for 2min/give EPI 1mg q3-min
- If Vfib/Vtach Shock @ 360J
- Continue CPR for 2min/Give Amnio 300mg
How do you begin the work-up for a patient with a bradyarrhythmia?
- Assess the stability of the patient
- Thorough history should be obtained for medications that may be the causative agent.
- The abnormal rhythm should be confirmed with a 12 lead EKG and basic labwork obtained.
- If patient is currently on a rate controlling medication, they should be discontinued or reduced if appropriate and a drug level obtained
Define a 1st-degree heart block
- a conduction delay that results in a PR interval >200 msec
Define a 2nd degree AV block type 1
Mobitz type 1 (Wenckebach) - Progressive delay in AV conduction with successive atrial impulses until an impulse fails to conduct. There is a shortening of each subsequent RR interval before the beat is dropped.
Define a 2nd degree AV block type 2
What is a complete heart block?
Complete heart block (CHB) occurs when all atrial impulses fail to conduct to the ventricles. There is complete dissociation between the atria and the ventricles.
What is the ACLS Bradycardia w/ pulse algorithm?
