​Kembara Xtra - Medicine - Atrial Fibrillation and Atrial Flutter

​Kembara Xtra - Medicine - Atrial Fibrillation and Atrial Flutter 

​PRINCIPLES FACTS 
 Both atrial fibrillation (AFib) and atrial flutter (AFlut) are covered in this article.


AFib is a paroxysmal or persistent supraventricular tachyarrhythmia marked by erratic ventricular response and fast, uncoordinated atrial electrical activity. Because the atrioventricular (AV) node experiences 400 to 600 atrial electrical impulses per minute or more frequently, the ventricular rate is typically high in patients.

AFlut: fast, well-organized atrial electrical activity during paroxysmal or persistent supraventricular tachyarrhythmias. On the ECG, the atrial rate is frequently seen as "saw-tooth" flutter (F) waves, especially in the inferior leads and V1. The atrial rate is normally between 250 and 350 beats per minute. The ventricular response may be regular and typically at a pace of 150 beats/minute since AFlut frequently co-occurs with 2:1 or 3:1 AV block.

AFib and AFlut are connected arrhythmias that might occasionally occur in the same patient. It's critical to distinguish between the two because doing so could have management ramifications.

Classifications in medicine:
- Paroxysmal: self-terminating episodes, usually lasting seven days or less
- Persistent: lasting for more than seven days, typically requiring medication or electrical cardioversion to restore sinus rhythm
- Permanent: It is impossible to maintain or reestablish sinus rhythm.
- Nonvalvular AFib: lack of artificial heart valve or moderate-to-severe mitral stenosis
Patients under 60 years old (perhaps with a genetic predisposition) with no clinical or echocardiographic indications of cardiovascular illness, including hypertension (HTN), develop lone AFib.

EPIDEMIOLOGY Young patients with AFib, particularly lone AFib, are more frequently male. Incidence/prevalence increases dramatically with age.

AFib incidence ranges from 0.1%/year in people under 40 to 1.5%/year in people over 80.
Lifetime risk: 25% for people under the age of 40, where AFlut is less common.
Prevalence rises with age, reaching 8% in those over 80 years old, with an estimated 0.4–1% prevalence in the general population and 2.7 million patients in America.

PATHOPHYSIOLOGY AND ETIOLOGY

Cardiovascular: infiltrative heart disease, acute coronary syndrome, congestive heart failure, valvular heart disease, cardiomyopathy, and pericarditis.
Pulmonary: pneumonia, obstructive sleep apnea, chronic obstructive pulmonary disease (COPD), and pulmonary embolism (PE)
Consumption of caffeine, nicotine, and ethanol
Endocrine conditions include hyperthyroidism and type 2 diabetes
Postoperative cardiac, pulmonary, or esophageal complications in obese patients
Idiopathic: solitary AFib
Amiodarone is iatrogenic. Premature atrial beats and/or bursts of tachycardia that originate in the pulmonary vein ostia or other places are frequently present in patients with paroxysmal episodes.
It is believed that atrial fibrosis or scarring affects many people with AFib, and that autonomic (vagal and sympathetic) tone may contribute to the onset of the arrhythmia.
● The phrase "AFib begets AFib" refers to the relationship between the existence of AFib and structural and electrical remodeling mechanisms that support arrhythmia maintenance in the atria.
Genetics
Although uncommon, familial forms do exist. The genetic causes of these occurrences are still being investigated.

RISK ELEMENTS
The three main risk factors for both AFib and AFlut are aging, high blood pressure, and obesity.

DURATIONAL PREVENTION
The most major modifiable risk factor for AFib is adequate HTN control, which has the potential to avoid the development of AFib due to hypertensive heart disease. In obese people, losing weight may reduce their risk of developing AFib. Consuming ethanol may cause AFib.

CONDITIONS OFTEN Associated with

HTN, stroke, and other cardiac conditions

DISEASE HISTORY

The severity of the symptoms might range from none to severe (angina, dyspnea, syncope) to mild (palpitations, dizziness, weariness, and poor exercise tolerance).

PHYSICAL EXAMINATION AFlut: similar to AFib but may have a regular pulse AFib: irregularly irregular heart rate and pulse, pulse deficit

DIFFERENTIAL DIAGNOSIS: Paroxysmal supraventricular tachycardia (Wolff-Parkinson-White [WPW], atrioventricular nodal reentry tachycardia [AVNRT]), multifocal atrial tachycardia, sinus tachycardia with numerous atrial premature beats.

DETECTION & INTERPRETATION OF DIAGNOSIS
It has not been demonstrated that pulse palpation-only screening for asymptomatic instances of AFib detects more cases than screening with ECG.
AFib is diagnosed by the ECG's lowamplitude fibrillatory waves, which lack identifiable P waves, and an erratic pattern of QRS complexes. In the absence of drugs that regulate heart rate, tachycardia frequently occurs.
The ECG serves as a diagnostic tool. Although the ventricular rate may need to be reduced to notice the waves, the classic symptom is saw-tooth F waves, which are typically best visible in the inferior leads. QRS complexes can be regular or irregular, and tachycardia is typically present.
Ambulatory rhythm monitoring is beneficial in validating suspected paroxysmal AFib or AFlut and monitoring for recurrence. Examples include telemetry, Holter monitoring, and event recorders.
Initial examinations (lab, imaging)
TSH, electrolytes, complete blood count, full metabolic panel, 2D transthoracic echocardiography, prothrombin time/international normalized ratio (INR) (if anticoagulation is being considered), and digoxin level (if necessary) are among tests that can be performed.

Tests in the Future & Special Considerations
Chest x-ray (CXR) for cardiopulmonary disease; ECG for indications of cardiac hypertrophy, ischemia, and/or other arrhythmias; Transesophageal echocardiogram to find left atrial appendage thrombus if cardioversion is intended; Sleep study may be helpful if sleep apnea is suspected.
Interpretation of Tests
Check for the presence of cardiomyopathy, valvular heart disease, atrial thrombus, and dilatation and fibrosis of the atrium.

TREATMENT
Decisions on heart rate control (control ventricular rate while allowing AFib to persist) or rhythm control (terminate AFib and restore normal sinus rhythm) and the choice of anticoagulation or not are the two main challenges in the management of AFib and/or AFlut.
Anticoagulation therapy reduces the risk of thromboembolism (mainly stroke) by around two-thirds.
For calculating the annual risk of thromboembolic event, there are several calculators available (ATRIA, CHA2DS2VASc). No anticoagulation may be necessary if the risk is sufficiently low or the risk of bleeding is considerable (assessment using the HAS-BLED tool may be helpful). Patient preference and clinical judgment are still crucial.

MEDICATION – Anticoagulation recommendations from the American Heart Association/American College of Cardiology (3)[C] (the same for AFib and AFlut):
- CHA2DS2VASc (CHF) scores ([1 point], "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," "1 point," The stroke risk assessment that is advised for patients with nonvalvular AFib is the CHA2DS2VASc (3)[C].
Anticoagulant medication may be skipped in individuals with nonvalvular AFib and a CHA2DS2VASc score of 0 in males or 1 in females (3)[C].
Oral anticoagulation medication may be considered in individuals with nonvalvular AFib and a CHA2DS2VASc score of 1 in males and 2 in females (with one non-sex-related risk factor) (3)[C].
 Oral anticoagulants should be used, unless contraindicated, in individuals with nonvalvular AFib who have any high-risk indicators for stroke (previous TIA, cerebrovascular accident [CVA]/thromboembolism), or who have a CHA2DS2VASc score of 2 in men or 3 in women.
- For the majority of patients with nonvalvular atrial fibrillation who need anticoagulant medication, DOAC (direct-acting oral anticoagulant)/NOAC (non-vitamin K oral anticoagulant) medicines are preferred over warfarin (3) [C]. Warfarin (3)[C] with maintenance of an INR of 2.0 to 3.0, dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis), or edoxaban (Savaysa) are some examples of oral anticoagulants. Depending on the kind and location of the prosthesis, patients with mechanical valves should receive warfarin treatment to maintain an INR of 2.0 to 3.0 or 2.5 to 3.5 (2)[B].
– The choice of an anticoagulant should be made specifically for the patient, taking into account cost, patient preference, tolerance, and the dangers of each medication.
ALERT
Prior to beginning treatment with direct thrombin or factor Xa inhibitors, renal and hepatic functioning should be assessed (3)[C].
About the safety of people receiving renal dialysis, there is little evidence available. With apixaban, additional dose considerations for people under the age of 80 or who weigh less than 60 kg are advised (3)[C]. Such agents' dosages might need to be customized. 
There are specific reversal drugs for urgent procedures or bleeding that poses a life-threatening threat:
 Dabigatran Idarucizumab (Praxbind)

For apixaban and rivaroxaban, coagulation factor Xa (recombinant), inactivated-zhzo (Andexxa). A decision regarding the long-term strategy—rate-control alone or rhythm control—must be made after achieving initial rate control in addition to anticoagulation. There are four kinds of drugs that can control ventricular rate: Metoprolol, verapamil, and diltiazem are examples of nondihydropyridine calcium channel blockers. Digoxin and amiodarone are examples of -blockers. Although the ideal ventricular rate target has not yet been determined, there is evidence that aggressive ventricular rate control (80 beats/minute) is not superior to more moderate rate control (i.e., resting heart rate 110 beats/minute).
It may be necessary to try to restore sinus rhythm in patients in whom rate control cannot be maintained or who still experience chronic symptoms despite good heart rate control.
randomized clinical trials (AFFIRM and RACE) comparing the outcomes of rate versus rhythm control found no difference in morbidity, mortality, or stroke rates in patients assigned to one therapy or the other. Restoration of sinus rhythm using electrical or pharmacologic cardioversion may significantly reduce the symptom burden of AFib or AFlut in many patients and may also be useful for controlling ventricular rate.

QUESTIONS FOR REFERENCE

It may be necessary to utilize more severe treatments to manage AFib or AFlut that is resistant to routine medical therapy (i.e., cannot achieve appropriate rate control with medication or develops considerable bradycardia as a result of treatment).

SURGICAL AND OTHER PROCEDURE
Patients with either AFib or AFlut may be candidates for electrophysiologic testing and ablation. Ablation is a treatment that is regarded as first-line therapy in the case of AFlut.
In symptomatic individuals with heart failure with decreased ejection fraction (HFrEF), ablation of AFib may be warranted to cut mortality and decrease hospitalization.
In patients who are considering having cardiac surgery for other reasons, such as the maze procedure or closure of the left atrial appendage, cardiac surgery may be an option.
In patients with long-term anticoagulation contraindications who are at elevated risk of stroke and systemic embolism, percutaneous left atrial appendage (LAA) closure using the WATCHMAN device may be investigated.

ALTERNATIVE & COMPLEMENTARY MEDICINE
To prevent prescription interactions, the use of herbal treatments, nutritional supplements, and vitamins needs to be carefully considered.

CONSIDERATIONS FOR ADMISSION, THE INPATIENT, AND NURSING
Patients needing hospitalization for a period of stabilization include those with substantial symptoms, RVR, AFib/AFlut brought on by an acute process (such as ACS, CHF, or PE), or those whose antiarrhythmic medication is just beginning.
Acute treatment for symptomatic AFib or AFlut patients:
- IV beta-blockers or nondihydropyridine calcium channel blockers (such as diltiazem, verapamil) for patients without preexcitation to control ventricular rate.
In individuals with significant left ventricular dysfunction or hemodynamic instability, IV amiodarone or digoxin may be explored.
In patients with hemodynamic instability or insufficient rate control, urgent direct-current cardioversion is advised.
Take into account starting an anticoagulant regimen.
CONTINUAL CARE
Think about choosing to consult an expert.


SUCCESSIVE RECOMMENDATIONS
patient observation
Warfarin's adequate anticoagulation levels should be checked every week during the beginning of treatment and at least once a month after it becomes stable.
Hepatic and renal functions should be reevaluated at least once a year if NOACs are being used.

Patients on warfarin should try to maintain a stable intake of vitamin K.

EDUCATION OF PATIENTS

Weight loss together with risk factor reduction has been shown to help patients who are overweight or obese control AFib.

PROGNOSIS
AFib and AFlut may increase morbidity and death, although underlying cardiac disease and adherence to medication determine the overall prognosis.

Embolic stroke, peripheral arterial embolization, bleeding while using anticoagulants, and tachycardia-induced cardiomyopathy with extended periods of poor rate control are complications.