Rhythm Control Rate Control

Transcription

1 IF ALREADY TAKING Class 1c OR Class 3 ANTI-ARRHYTHMIC DRUG Guidelines for the Management of Newly diagnosed Atrial Fibrillation Identify and Treat Major Primary Causes ACS, Massive PE, Sepsis, Severe LRTI, Pericarditis, Metabolic / electrolyte disturbance, Thyrotoxicosis, Drug effects / Toxicity *These guidelines do NOT apply in the context of these conditions* Haemodynamic Instability - SBP < 90mmHg - Hypoperfusion - Hypoxaemia with AHF * See ALS Guidelines Major Comorbid CVS Condition - Congenital HD - Cardiac transplant - Cardiomyopathy - Pregnancy - Channelopathy - Severe COPD/ILD Yes Refer to Cardiology No Duration of Atrial Fibrillation < 48hr > 48hr Rhythm Control Rate Control Monitored bed ED / D55 / ACU *Give Treatment dose Clexane if not on VKA / NOAC Manage on Medical Unit Risk of Proarrhythmia - BP and evidence LVH - Previous MI or angina - Known CCF Ventricular Rate Control Aim HR < 80bpm at rest and HR <110bpm walking No Yes iv Atenolol & iv Flecainide Consider IV Amiodarone vs urgent DC Cardioversion n Pharmacological Cardioversion < 48h from onset No Yes Clinical Symptoms and signs of heart failure Yes PO Digoxin (or IV if NBM) No PO Atenolol or if contraindicated PO Diltiazem Urgent DC Cardioversion Discharge with 4 weeks NOAC and Cardiology OP follow up Target HR Achieved If not contact Cardiac ANP or CATS 70040, Cardiology SpR QMC or City Consult Thrombo-embolic Prophylaxis Guidance if CHADSVASC 2 Consult Thrombo-embolic Prophylaxis Guidance

2 Thrombo-embolic Prophylaxis The following chart is based on the European Society of Cardiology Guidelines (2010) for the management of atrial fibrillation. The CHA 2 DS 2 VASc and HAS-BLED scores are the most accurate risk indices for the risk of stroke and bleeding in this context. Calculate the points for each of these risk scores and look up the advised strategy in the anticoagulation therapy table using the key below: No anticoagulation therapy recommended VKA, NOAC or no anticoagulation therapy (NOAC preferred) Consider VKA, or NOAC, or consult specialist No anticoagulation therapy recommended VKA or NOAC recommended

3 Atenolol (Oral) Atenolol (IV) Amiodarone (IV) Digoxin (Oral) Digoxin (IV) Diltiazem (Oral) (Angitil SR) Flecainide (IV) Usual Starting Dose Drug Administration 25 50mg od Starting dose in elderly and renal impairment should be 25mg. Orally 2.5mg (repeat at 5-10 min intervals up to a maximum 10mg dependant on BP and Heart rate) Give IV over 5 minutes (0.5mg per minute). Give in 2.5mg doses leaving 10 minutes between bolus doses Loading dose: 300mg IV over 1h into a central line or large peripheral vein; followed by 900mg over 23h into a central Line Loading dose 300mg IV in 250ml Dextrose 5% over 1h; followed by 900mg in 500ml Dextrose 5% over 23h. Given via a central line or large peripheral vein Dose Range 25 50mg od 5-10mg Switch to oral amiodarone Loading dose dependent on renal function. Usually two doses of 500 micrograms 6h apart Orally - The loading dose will need to adjusted dependent on renal impairment micrograms od Halve dose if patient also on Amiodarone Usually dose of 500 micrograms. Additional doses of 250 microgram doses at 6h intervals up to 8-12 micrograms/kg IV loading dose may need to be adjusted dependent on renal impairment and body wt. Dilute in 100ml Sodium Chloride 0.9% administered over 30 minutes micrograms od Halve dose if patient also on Amiodarone 90mg bd (60mg bd patients who are elderly or have renal impairment see below) Orally 60mg- 180mg bd Onset of Action 2-4 hours Immediate Variable may be 4-6 hours 0.5 to 2 hours 5 to 30 minutes 3 hours Minutes Half life Time to Peak Concentration Duration of Action Renal Impairment Main Contraindications 6-7 hours; Can be up to hours in renal impairment 6-7 hours Variable hours Time for elimination can take 9-44 days 31 to 53 hours - affected by renal impairment 31 to 53 hours - affected by renal impairment 2mg/kg (maximum dose 150mg) 6-8 hours 7 19 hours 3 hours < 5 mins Variable 2 to 6 hours 0.5 to 4 hours 4-6 hours minutes hours, may be prolonged.e.g CKD Mild (Crcl=20-50ml/min) normal dose. Moderate (Crcl ml/min) maximum dose of 50mg daily. Severe (Crcl <10ml/min) maximum dose 25mg daily Up to 12 hrs One dose Acute decompensated LV systolic dysfunction Cardiogenic shock 2 nd /3 rd degree AV block Severe sinus bradycardia Hypotension Asthma/COAD Variable. If patient fully loaded the effects can last for a month or greater No dose adjustment necessary Sinus bradycardia 2 nd /3 rd degree AV block Thyroid dysfunction Severe respiratory failure Iodine hypersensitivity >24 hours >24 hours 12 hours Reduce doses in renal impairment. See intranet for examples of doses in renal impairment Ventricular Fibrillation Pre excitation syndromes eg:wpw 2 nd /3 rd degree AV block 60mg bd (Tildiem Retard) Structural heart disease including myocardial infarction and cardiac failure Hepatic impairment Dilute in 100ml 5%Dextrose,administer over 30 minutes 2mg/kg (max. dose 150mg) 4 hrs but can reduce arrhythmias for between 6-24 hrs (av 13 hrs) Reduce dose by 50% if creatinine clearance <35ml/min Left ventricular systolic dysfunction Cardiogenic shock 2 nd /3 rd degree AV block Severe sinus bradycardia Hypotension Beta blockers Monitoring Drug Interactions (See BNF) Pulse for Bradycardia ECG BP for hypotension Blood sugars in diabetics Bronchospasm especially in asthmatics see CI Caution with concomitant Diltaizem or Verapamil Pulse for Bradycardia - may be necessary to administer IV atropine ECG, BP for hypotension Blood sugars in diabetics Bronchospasm especially in asthmatics see CI Caution with concomitant Diltiazem or Verapamil Baseline tests: Heart rate, TFT s LFT s, CXR and PFT s for patients with pulmonary disease ECG: QT prolongation Monitor INR with warfarin. Digoxin level may need to be checked. Contraindicated with simvastatin 40mg or above. Can cause QT prolongation, will interact with other drugs. Pulse, renal function, keep K levels >4 mmols/l Plasma levels should be checked where clinically indicated. Signs of toxicity loss of appetite, nausea and vomiting, diarrhoea, confusion, blurred or yellow-coloured vision. Digoxin levels checked pre-dose or >6h post dose Consult BNF Consult BNF Pulse for bradycardia BP for hypotension Caution with concomitant beta-blockers Correct electrolyte disturbances before using Flecainide ECG monitoring Caution with concomitant anti-arrhythmic agents

4 Explanatory Notes for the Management of Newly Diagnosed Atrial Fibrillation/Flutter Guidelines Objective These guidelines have been developed to improve the management of patients with newly diagnosed atrial fibrillation (AF) and flutter (AFl). The guidelines should be used in combination with clinical judgement to inform the clinical decision making process. The guidelines: 1. assist the clinician in acute management of the patient 2. include reference tables in order that the patient can make an informed decision about stroke risk reduction 3. provide at a glance information tables for the most commonly used drugs 4. provide clear instruction when referral to a cardiac specialist service is indicated. Scope of Guidelines The guidelines are intended to assist clinicians managing patients with newly diagnosed AF/AFL in the emergency department, acute medicine and other medical specialties. The guidelines do not pertain to AF/AFl in other contexts such as Primary Pulmonary Hypertension (PPH), critical illness or post surgical AF/AFl including coronary artery bypass grafting. However, the guidelines should be broadly applicable to atrial fibrillation/flutter following uncomplicated elective non-thoracic surgery.

5 The Guidelines - Algorithm (Page 1) The first page of the guidelines provides an algorithm for AF/AFl management. A list of important conditions associated with AF is provided which require referral to cardiology. This is not an exhaustive list of AF/AFl causes and the clinician is advised to perform a thorough medical assessment to identify other relevant conditions. It is important that the decision to assign the patient to a rhythm or rate control strategy is made early by the admitting clinician and recorded in the medical notes. The algorithm provides a recommendation on the appropriate strategy and details the subsequent management. Rate Control All patients initially assigned to a rate control strategy on QMC campus should be referred to the Cardiac Assessment Team (CATS) or Cardiac ANP and will be reviewed on a standard working day within 24h on the ward. If the patient is to be assigned to long term rate control strategy the patients will remain under the care of the admitting clinician provided satisfactory ventricular rate control can be achieved using the algorithm provided. If satisfactory rate control is not achieved then the CATS / Cardiac ANP can be contacted to review the patient and advise on further management. Patients at the City Campus should be referred to the on-call Cardiology Registrar. The patient may initially be assigned to rate control, perhaps because they presented with asymptomatic AF/AFl or with AF/AFl >48h duration. In these circumstances the patient may be deemed suitable for elective cardioversion and the cardiology team will recommend and instigate the appropriate cardiac rhythm management when the patient is reviewed. Rhythm Control Patients who are assigned to an initial rhythm control strategy will receive medical or electrical cardioversion in the emergency department or in a monitored bed within the cardiology unit. These patients will all be taken over by the cardiology team. To reduce thromboembolic risk, a therapeutic dose of enoxaparin should be administered when assigned to a rhythm control strategy.

6 It is recommended that those patients who are treated and discharged from the emergency department without admission to hospital are discussed with the emergency cardiology team and/or formally referred to the Arrhythmia Clinic. Anticoagulation naïve patients should receive 4 weeks of NOAC upon discharge to minimize risk of late thromboembolic complication. The Guidelines - Thrombo-embolic Prophylaxis Reference Tables(Page 2) For all patients assigned initially to a rate or rhythm control strategy it is imperative that a senior member of the A&E or medical team decides with the patient a plan for stroke risk reduction before discharge. This decision should be documented, and the rationale for this if appropriate, recorded in the medical notes. In general, oral anticoagulation is underused in AF 1 and page two of the guidelines provides the clinician with evidence based data on stroke risk reduction and bleeding risks associated with anticoagulant and antiplatelet therapy. These risk scores are derived from large patient cohorts and are the most accurate and applicable models available. All risk models/indices are inherently imperfect and the ROC for the risk models provided is between 0.65 and This means that the predictive accuracy that a bleeding event or stroke will/will not occur in an individual patient is not greater than 70%. Notwithstanding the tables should improve the quality of clinical information that can be given to all patients so that an informed decision can be made with their doctor. Two examples of how to use the tables is provided below. CHA 2 DS 2 VASc Index See Appendix 1 for definition of criteria. Stroke risk in the CHA 2 DS 2 VASc include patients presenting with radiographically proven strokes with neurological symptoms and signs, transient ischaemic attacks and patients presenting with vague neurological symptoms suggestive of cerebral ischaemia without confirmatory diagnostic tests 2. Typically, up to one third of patients with these diagnostic codes would develop disabling neurological

7 symptoms and signs but in the popoluation with AF/AFL this percentage may be doubled. It is hypothesized that this is due to a greater number of strokes in the AF/AFL population being secondary to a cardioembolic origin rather than noncardioembolic 3. In the AF population 50% of strokes are thought to be cardioembolic, 25% non-cardioembolic and 25% undetermined. The superior efficacy of warfarin compared to aspirin is largely attributed to a reduction in cardioembolic stroke. Therefore, although aspirin demonstrates efficacy in thrombo-embolic prophylaxis, the effect on disabling cardioembolic stoke is not established. HAS-BLED Score See Appendix II for definition of criteria. There are several risk models available for predicting bleeding with oral anticoagulation. The observed risks depend on the characteristics of cohort selected. The HAS-BLED risk model 4 is recommended by the European Society of Cardiology guidelines for the management of atrial fibrillation This is derived from nearly 4000 european patients in the EuroHeart Survey. The risk of bleeding with aspirin and warfarin is similar. A HAS-BLED score >3 indicates a high bleeding risk of bleeding but anticoagulants may still be appropriate and may require careful monitoring. Thrombo-embolic Prophylaxis Decision In weighing the risk of major bleeding the clinician needs to consider the predictive power of the HAS-BLED score and balance the risk of disabling stroke against an acceptable risk of non-fatal and fatal bleeding. Additionally, the clinician will appreciate that the models are a crude tool and a patients risk profile does not transform as he/she passes a 75 th birthday but increases in a more linear pattern with advancing age. In some circumstances whether the patient should be treated with aspirin or warfarin can be unclear and necessitates a clinical judgment and discussion with patient. Such scenarios are relatively uncommon and Cardiac Rhythm Management service can provide an opinion if

8 requested by the supervising consultant. If the clinician decides to prescribe warfarin for the patient then in almost all cases this can be started as an outpatient by the anticoagulation service. Inpatient anticoagulation and/or heparinisation are only expected to be required in exceptional circumstances such as those patients presenting with embolic events or with evidence of an intracardiac mass. These patients are beyond the scope of these guidelines and direct referral to the oncall cardiologist is more appropriate. The Guidelines - Drug Information Reference Table (Page 3) The final page of the guideline provides drug information relevant to the management of AF/AFl. The table highlights the most common and important considerations. The tables will resolve most problems but are not exhaustive and the clinician is advised to consult the British National Formulary ( or contact the Pharmacist in Medicines Information if in doubt. Nottinghamshire Area Prescribing Committee AF anticoagulation prescriber decision support tool The APC has clear guidance on which patients require continuing oral anticoagulation for non-valvular atrial fibrillation. Within this document are decision support tools to determine who requires oral anticoagulation, whether a patient is more suited to a vitamin K antagaonist (ie. Warfarin) versus a noval oral anticoagulant, and instructions on safe prescribing and monitoring. 5

9 References 1. Lancet Neurol 2007; 6: JAMA. 2001; 285(22): Cerebrovascular Disease 2000; 10: Chest 2010; 138: NUH / NAPC atrial fibrillation (non-valvular): prescriber decision support on anticoagulation, 2015

10 Appendix I CHA 2 DS 2 VASc Risk Index 8 Score Letter Criteria Definition 1 C Chronic Heart Failure/LV Dysfunction Including recent hospitalization with decompensated HF ICD-9-CM codes , , , , 428.x, or or moderate-severe LVSD (LVEF<40%) 1 H Hypertension History of hypertension only 2 A 2 Age Age>75y 1 D Diabetes 2 S 2 Stroke 1 V Vascular disease Diabetes mellitus (Insulin and non-insulin treated) Prior cerebral ischemia including stroke or TIA Myocardial infarction, complex aortic plaque and PAD, including prior revascularization, amputation due to PAD, or angiographic evidence of PAD) 1 A Age Age 65-74y 1 Sc Sex category Female gender International classification of diseases Ninth and Tenth Revisio;n World Health Organisation

11 Appendix II HAS-BLED Bleeding Risk with OAC Score Letter Criteria Definition 1 H Hypertension Systolic BP>160mmHg 1 or 2 A Abnormal renal and liver function (1 point each) Renal disease including chronic dialysis, transplantation or creatinine>200μmol/l. Abnormal liver function includes cirrhosis or significan LFT derangement including bilirubin>2xuln or AST/ALT/AP>3xULN. 1 S Stroke Stroke 1 B Bleeding Previous bleeding history and/or predisposition to bleeding, e.g. bleeding diasthesis, anaemia, etc. 1 L Labile INRs Unstable INRs or TTR<60% 2 E Elderly Age>65y 1 or 2 D Drugs/Alcohol use Concomitants use of antiplatlets or NSAIDs. Alcohol use>8u/week Review Date: December 2020