A study on clinical profile and the utility of 72 hour Holter monitoring in acute ischemic stroke and Transient ischemic attack(TIA) patients.

Stroke is a second leading cause of death worldwide that we frequently encounter in hospital setting which can be often preventable and a timely treatment can reduce its morbidity.

The risk factors for stroke are age, sex, smoking habits, hypertension, diabetes, atrial fibrillation/flutter.

Atrial fibrillation/flutter (AF), a strong risk factor for stroke and most important finding on cardiac workup in patients with ischemic stroke.

AF is associated with a high risk of cardio embolic stroke while thromboembolic complications bear an annual risk of 3–6%, which is 5 to 7 times greater than that of controls with sinus rhythm.

The association between cerebrovascular and cardiovascular diseases is mainly due to sharing of common risk factors.AF associated stroke occurred in one third of all patients and was associated with a distinct profile of recurrent, severe and disabling stroke.

The features of AF such as duration, episodic frequency, and asymptomatic presentation makes its detection challenging and elusive to bedside screening measures that includes pulse monitoring and routine ECG.

Paroxysmal AF or subclinical AF is a self–terminating recurrent form of cardiac arrhythmia that present as a brief single episode of arrhythmia or cluster of abnormal rhythm of variable duration, sometimes evolving into more persistent and permanent form.

In clinical practice, infrequent prolonged ECG-monitoring might lead to under diagnosis of underlying atrial fibrillation and can lead to less effective treatment in prevention of stroke.

Several studies have explored the use of noninvasive and invasive cardiac monitoring devices to identify AF but with variable success.

Patients with subclinical AF leading may ensue hospitalization only with the evidence of sinus rhythm and thus, typically receive antiplatelet therapy which is inferior to anticoagulant therapy for clinically apparent AF.

The occurrence of AF may be also be missed on bedside monitoring by routine ECG .Hence, use of holter can be advantageous in such cases to record all the events.

In a study conducted by  Kwon S et al , Compared to the 24-hour Holter test, AF detection could be improved with 72-hour single-lead ECG monitoring.

In a study conducted by D Hughes and et al, the number of abnormal results that are detected after the initial 24 h period decreases significantly with only minimal arrhythmias detected on day 4 or 5.

Therefore by limiting  holter monitoring  to 24–72 h, the amount of arrhythmias detected per day of recording would increase dramatically.

In a  prospective, multicenter study conducted by martin grond et al demonstrated that integrating a prolonged 72-hour ECG monitoring into a standardized diagnostic and therapeutic assessment protocol improves detection of previously undiagnosed AF in survivors of a stroke or TIA  can detect the AF which might be missed during bedside monitoring

The 2016 Atrial Fibrillation guideline of the European Society of Cardiology recommends at least 72 h of Holter monitoring.Early detection of AF using this method is a cost effective approach for the burden of the disease.

However, atrial fibrillation might escape routine short term electrocardiogram (ECG)-monitoring if it occurs intermittently, because the episodes are often short, occur in irregular patterns, and are frequently asymptomatic.Prolonged ECG-monitoring is adequate, if underlying paroxysmal atrial fibrillation is suspected.

The detection of atrial fibrillation in patients with acute ischaemic stroke is of major clinical relevance,  because it usually shifts the secondary prevention therapy from antiplatelet drugs to oral anticoagulation.

Furthermore, 72-hour monitoring seems feasible in most healthcare settings because patients with stroke are usually managed as inpatients for at least three days, allowing implementation of the prolonged monitoring without changes in care pathways.

Atrial fibrillation-related strokes can be more severe than those from other causes and patients with stroke and atrial fibrillation have a high risk of recurrent ischaemic events.

Once identified introduction of oral anticoagulant therapy provides an additional 40% risk reduction in recurrent stroke compared with antiplatelet therapy.

Oral anticoagulation therapy leads to a 60–70% relative risk reduction of recurrent strokes in  those with atrial fibrillation, compared with placebo.

Further,recent evidence suggests that therapeutic oral anticoagulation (international normalized ratio 2 to 3) may also be associated with reduced stroke severity, if ischemic stroke does occur in patients with AF

Given that ischemic stroke with AF is associated with greater disability and mortality than those without AF, establishing the presence of underlying AF is of clear clinical importance.

Guidelines recommend that patients with atrial fibrillation should be given oral anticoagulants, irrespective of whether they have paroxysmal (defined as episodes of at least 30 s, but occurring for fewer than 7 days or persisting atrial fibrillation).