AD 6th Oct issue | Page 38

no further attempts are made to

maintain sinus rhythm . 11

The characteristic findings on a

12-lead ECG are the absence of discernible P waves , and QRS complexes that occur at irregular intervals ( see figure 2 ). Given AF ’ s potential to be paroxysmal , the diagnostic yield is increased with ambulatory monitoring using Holter

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urgently required in anyone with haemodynamically unstable AF , most patients with AF are haemodynamically stable . A decision then needs to be made regarding whether to pursue rhythm or rate control . A rhythm control strategy involves attempting to convert the patient to sinus rhythm and to maintain this rhythm . On the other hand , a rate control strategy

monitoring ( see figure 3 ), wearable

attempts to bring the heart rate down

devices , smart watches ( see figure 4 ),

to an acceptable target range which is

or implantable loop recorders ( see

less likely to cause symptoms or ven-

figure 5 ). Inpatient cardiac monitor-

tricular dysfunction .

ing ( see figure 6 ) is used in the pres-

The decision to choose rhythm

ence of a TIA and stroke to screen for AF . Longer-term screening for

or rate control is guided by the patient ’ s individual circumstances .

AF with insertable cardiac monitors

While early rhythm control strat-

or non-invasive methods is recom-

egy , instituted within one year of

mended in selected patients , such as

diagnosis , may reduce the risk of

those with embolic stroke of unde-

cardiovascular death and stroke , it

termined source . 12

is associated with a higher rate of

Regular opportunistic screen-

complications related to therapy

ing for AF is recommended for all patients over the age of 65 . 12 This may be performed by pulse pal-

such as drug-induced bradycardia , thyroid disease , QT prolongation , and serious but rare complications

pation screening for an irregular rhythm , followed by an ECG to confirm the diagnosis . 12 The cost-effectiveness of frequent AF screening in

of AF ablation ( for example , pericardial tamponade ). 16 Compelling reasons to pursue rhythm control include patient preference ,

this age group has been confirmed

high ventricular rates refractory to

in multiple analyses . 13

attempted rate control , and unpleas-

Refer those with newly diag-

ant symptoms of AF despite ade-

nosed AF for a transthoracic echo-

quate rate control .

cardiogram , as information on left

atrial size , left ventricular function ,

RATE CONTROL

and the presence of mitral stenosis

Beta blockers , non-dihydropyridine

impacts management . Also inves-

calcium channel blockers ( CCBs ) and

tigate for OSA , which has a strong association with AF . 14 Order electrolytes and thyroid stimulating hor-

digoxin form the backbone of both acute and long-term rate control in AF . Oral beta blockers and non-dihy-

mone if the patient is not acutely

dropyridine CCBs are first-line agents ;

unwell ; AF may be the only mani-

however , their simultaneous use

festation of such abnormalities , and

should be avoided because of the risk

may resolve with appropriate treat-

of complete heart block . Digoxin can

ment of the underlying disorder . 12

be added to either beta blockers or

Routinely screening for CAD in

non-dihydropyridine CCBs for addi-

patients with AF is controversial . It is

tional rate control , or as a standalone

well known that myocardial ischae-

rate control agent if these two agents

mia can trigger AF , that those with AF

are contraindicated , for example ,

have higher rates of subclinical CAD compared with the general popula-

Figure 1 . Left atrial appendage .

because of symptomatic hypotension .

In addition to its role in rhythm

tion , and that the presence of CAD affects the management of AF , given the latter is a contraindication to the

CAD in patients with AF is of benefit . Current guidelines do not make

MANAGEMENT

THE management of AF is multi-

of stroke and management of risk factors .

control , amiodarone can be useful to slow the rate in the acute setting in patients with highly sympto-

use of certain antiarrhythmics , such as flecainide . 15 However , there is no evidence that routine screening for

recommendations regarding routine screening for CAD , beyond performance of a 12-lead ECG

11 , 12

.

pronged and includes choice and enactment of rate or rhythm control , prevention

Rate vs rhythm control

While electrical cardioversion is

matic AF or in those with depressed left ventricular systolic function . A reasonable target is a PAGE 40

Figure 2 . AF on ECG .

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