of Recent Onset Atrial Fibrillation: The Obvious Solution?
P. A
LBONIIn the clinical setting, some patients with recurrent atrial fibrillation (AF) present with episodes that are not frequent (< 1 per month) and are haemo- dynamically well tolerated, but which are long enough to require emergency room (ER) intervention or hospitalisation. These patients need treatment, but long-term oral prophylaxis or catheter ablation may not be the most appropriate first-line therapy. Rather, a good method of treatment in this group of patients might be the ‘pill-in-the-pocket’ approach, consisting of single-dose oral ingestion at the time and place of palpitation onset. This type of treatment has already been investigated in studies carried out in hos- pital in patients with recent-onset AF. The oral drugs that have been used to convert recent-onset AF to sinus rhythm are class IA, class IC, and class III anti-arrhythmic agents [1–7]. The class IC agents flecainide and propafenone have the advantage of being conveniently administered in a single oral dose that acts rapidly and causes minimal side effects [1, 6, 8–16]. The efficacy of a single oral loading dose of flecainide and propafenone in converting recent-onset AF to sinus rhythm has been documented by several placebo- controlled trials [1, 6, 8, 9, 11, 13, 16]. Both drugs showed similar efficacy, and their success rate varied from 58% to 95% [1, 6, 8–13], depending on the duration of AF and the observation period after drug administration. In all controlled studies, a low incidence of adverse effects has been reported [1–6, 8–13, 15, 16]. The most serious side effect seems to be the appearance of a transient atrial flutter with high ventricular rate owing to 1:1 atrioventricu- lar (AV) conduction (in about 1% of patients).
Very recently, out-of-hospital treatment with the ‘pill-in-the-pocket’
Division of Cardiology and Arrhythmologic Centre, Ospedale Civile, Cento (Ferrara),
Italy
approach has been investigated in an Italian multi-centre study [17].
Inclusion criteria were as follows:
– Age between 18 and 75 years with requirement for ER intervention for recent onset AF (< 48 h).
– History of palpitation with abrupt onset, haemodynamically well tolerat- ed (absence of symptoms such as dyspnoea, pre-syncope, or syncope).
– Number of episodes in the last year < 1 per month.
– Absence of cardiological symptoms apart from the arrhythmic episodes.
Patients with contraindications to class IC agents were excluded. The patients could be treated either in the ER or in the cardiology ward. For AF conversion, oral propafenone and flecainide were administered in a single dose according to the weight of the patient: flecainide 300 mg if the patient weighed ≥ 70 kg, otherwise 200 mg; propafenone 600 mg if the patient weighed ≥ 70 kg, otherwise 450 mg. The drug treatment was considered
‘successful’ if the conversion time to sinus rhythm was within 6 h after drug administration, without severe side effects.
Two hundred and sixty-eight patients with recent-onset AF received an in-hospital oral loading dose of flecainide and propafenone. Of these, 58 were ruled out of the out-of-hospital treatment: in 3 (1%) exclusion criteria emerged during echocardiographic recording, in 41 (14%) the drug was not effective in restoring sinus rhythm within 6 h, and in 14 (6%) the drug induced side effects (transient hypotension in 4, atrial flutter in 7, one of whom had 1:1 AV conduction, and slightly symptomatic bradycardia in 3).
The remaining 210 patients (age 59 ± 11 years) were discharged on fle- cainide or propafenone for ‘pill-in-the-pocket’ treatment of recurrent AF.
One hundred and eighteen patients had no signs of heart disease and the remaining 92 (43%) had mild heart disease. The mean follow-up was 15 ± 5 months; 4 patients were lost just after enrolment. Of the remaining 206 patients, 41 (20%) did not experience any arrhythmic recurrences during the follow-up period and 165 reported 618 episodes of palpitation with abrupt onset, 569 of which were treated with flecainide (64 patients) or propafenone (101 patients). The drug was effective in 534 out of 569 arrhythmic episodes (94%).
Similar results on the efficacy of class IC drugs were recently reported by
Capucci et al. [16], who investigated in hospital the reproducibility of effica-
cy of an oral loading dose of propafenone in restoring sinus rhythm in
patients with recurrent AF. Efficacy was evaluated by electrocardiographic
monitoring and was reproducible in 93% of the patients. In the Italian multi-
centre study, time to symptom resolution after drug ingestion was 113 ± 84
min (median 98 min). Sixteen arrhythmic episodes were interrupted after
an interval of more than 6 h without the patients contacting the ER. Twenty-
six episodes (5%) required ER intervention, and 10 of these (2%) also
required hospitalisation of the patient. Out of the 618 episodes, 49 were not treated, mainly because of drug unavailability, and 5 (10%) of these required ER intervention. Thus, during the follow-up period, the number of ER con- tacts among the treated and untreated arrhythmic episodes was 31 (5%), and 10 of them also needed hospitalisation. Out of the 31 calls for ER interven- tion, 19 were due to AF lasting more than 6 h, 1 to acceleration of heart rate after drug ingestion (atrial flutter with 1:1 AV conduction), and 11 to anxiety (request for ER intervention although palpitation had ceased).
During follow-up, the number of calls for ER intervention per month was significantly lower than in the year before the target episode (4.9 versus 45.6, P < 0.001). The number of hospitalisations per month during the follow-up period was also significantly lower (1.6 versus 15.0 P < 0.001). Adverse effects during one or more arrhythmic episodes were reported in 12 out of the 165 patients (7%) who utilised the drug during the follow-up. One patient (0.7%) felt a marked acceleration of heart rate after drug ingestion and contacted the ER; electrocardiogram showed atrial flutter with 1:1 AV conduction. This means that successful in-hospital treatment does not com- pletely prevent the appearance of atrial flutter at high rate during follow-up.
The remaining 11 patients reported non-cardiac side effects such as nausea, asthenia, or vertigo.
These results show that out-of-hospital treatment of recurrent AF using the ‘pill-in-the-pocket’ approach is feasible and safe, in view of the high rate of patient compliance and the very low incidence of adverse effects. Data from the Italian study show that the ‘pill-in-the-pocket’ strategy with fle- cainide or propafenone is effective in over 90% of arrhythmic episodes after patient selection on clinical grounds and on the basis of the results of in- hospital treatment. Episodic treatment minimises the need for ER and hospi- tal admission during the acute event. It is noteworthy that about one-third of ER contacts were due to anxiety. Therefore, psychological management of these patients (particularly reassurance) could further reduce calls for ER intervention. The marked reduction in ER and hospital admissions, besides avoiding prophylactic treatment, will help to reduce the economic impact of AF, although in only quite a small group of patients with this tachyarrhyth- mia. The safety of this approach without previous evaluation of in-hospital treatment remains to be investigated; therefore, at present, oral flecainide or propafenone must be tested once in hospital before prescription for out-of- hospital treatment.
Contraindications to this treatment, listed in Table 1, must always be
considered. If the patient is undergoing chronic treatment with anti-arrhyth-
mic drugs, the loading dose of flecainide or propafenone cannot be utilised,
but if the patient appears suitable for the ‘pill-in-the-pocket’ treatment, the
chronic therapy can be suspended and the loading dose given during the
next AF relapse. AV nodal blockers ( β-blockers, verapamil, diltiazem) for treatment of hypertension or other diseases can be administered chronically.
Before discharge, patients should be given some recommendations:
– They should take the drug 5 min after any onset of typical palpitation – After taking it, they should rest (sitting or lying down) until the palpita-
tion has stopped or at least 4 h have passed
– They should contact the ER if palpitation has not ceased 8 h after they took the drug, or if they have symptoms that have not occurred during previous arrhythmic episodes (e.g. dyspnoea, pre-syncope, or syncope), or if they feel a marked increase in heart rate after taking the drug – They must take no more than one oral dose during any 24-h period – They must not take less than the prescribed dosage of the drug
The practical management of patients suitable for out-of-hospital treat- ment with the pill-in-the-pocket approach is summarised in Fig. 1.
Table 1. Contraindications to treatment using the ‘pill-in-the-pocket’ approach Hyperthyroidism
Left bundle branch block or bifascicular block Ischaemic heart disease
Dilated or hypertrophic cardiomyopathy History of heart failure
Severe valvular heart disease Chronic cor pulmonale
Left ventricular dysfunction (ejection fraction < 50%) Long QT interval or Brugada syndrome
Bradycardia–tachycardia syndrome (resting sinus rate < 50 bpm) Documentation of previous episodes of second- or third-degree AV block Acute disease
Very severe chronic disease Renal or hepatic insufficiency
Previous hypokalaemia (potassium level < 3 mmol/l) Suspected or known pregnancy
Current prophylactic anti-arrhythmic treatment
References
1. Villani GQ, Rosi A, Piepoli M et al (1990) The efficacy of oral treatment with flecai- nide for paroxysmal atrial fibrillation: correlation with plasma concentration. G Ital Cardiol 20:564–568
2. Capucci A, Lenzi T, Boriani G et al (1992) Effectiveness of loading oral flecainide for converting recent-onset atrial fibrillation to sinus rhythm in patients without organic heart disease or with only systemic hypertension. Am J Cardiol 70:69–72 Fig. 1.Practical management of patients suitable for the ‘pill-in-the-pocket’ approach
Patients 75 years with mild heart disease or none, requiring ER intervention for an episode of recent-onset AF (< 48 h), with a history of palpitations of abrupt onset, not very frequent ( 1 per month), haemodynamically well tolerated but lasting long enough to require hospital intervention, with no contraindications to class IC drugs after clinical and electrocardiographic evaluation.
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In-hospital treatment (ER or ward) with a loading dose of flecainide (300 mg, or 200 mg if body weight < 70 kg) or propafenone (600 mg, or 450 mg if body weight
< 70 kg).
If treatment successful (AF interruption within 6 h, without severe side effects), an echocardiogram and some laboratory tests (thyroid hormones, creatinine, transaminases, kalaemia) must be requested.
If contraindications do not emerge, the drug used in hospital can be prescribed at the same dose for out-of-hospital interruption of AF episodes.
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