Simplified electrocardiogram sampling maintains high diagnostic capability for atrial fibrillation: implications for opportunistic atrial fibrillation screening in primary care. Performance of a New Leadless Implantable Cardiac Monitor in Detecting and Quantifying Atrial Fibrillation Results of the XPECT Trial
AIMS Atrial fibrillation ( AF ) is a major cause of morbidity , mortality , and health re source consumption . However , as many patients with chronic AF are asymptomatic , rapid , accurate opportunistic screening is needed in primary care to detect AF . Conventional electrocardiogram ( ECG ) technology is too clumsy and time consuming for mass opportunistic screening , thus technology that allows easy , rapid , yet accurate AF screening is required . To address this requirement a prototype h and -held electrode assembly was developed . We hypothesized that a 6-lead frontal-plane ECG acquired from this apparatus in a seated , clothed patient would be as accurate at detecting AF as conventional 12-lead ECG in the undressed , supine patient ( the ' gold st and ard ' ) . METHODS AND RESULTS Electrocardiograms were obtained from 78 patients with AF and 79 with sinus rhythm ( SR ) . All had a  conventional 12-lead ECG  , a 6-lead ECG from conventionally positioned limb electrodes , a supine 6-lead recording using the prototype recorder placed on the lower thorax/upper abdomen , and a 6-lead prototype recording in the seated patient , the latter with loosened clothing only . Electrocardiograms were r and omly and blindly assessed by two cardiologists for ( i ) diagnosis of AF vs. SR and ( ii ) tracing quality ( subjectively assessed as good , adequate , or bad ) . Compared with conventional 12-lead ECG recordings , all ' new ' recording methods performed satisfactorily with sensitivities ≥90 % ( 90 - 99 % ) , specificities ≥94 % ( 94 - 100 % ) , positive predictive values ≥94 % ( 94 - 100 % ) , negative predictive values ≥90 % ( 90 - 99 % ) , and accuracies ≥93 % ( 93 - 99 % ) . Tracing quality was higher in conventional 12-lead recordings ( 71 and 80 % were assessed as good by the two observers ) compared with conventional 6-lead ( 57 and 59 % ) , supine prototype ( 41 and 31 % ) , and sitting prototype ( 39 and 19 % ) . CONCLUSIONS Despite inferior electrocardiographic quality a 6-lead frontal plane ECG acquired by a simple prototype h and -held electrode assembly allowed reliable differentiation of AF from SR compared with st and ard 12-lead ECG Background —Current methods for detecting atrial fibrillation ( AF ) have limited diagnostic yield . Continuous monitoring with automatic arrhythmia detection and classification may improve detection of symptomatic and asymptomatic AF and subsequent patient treatment . The study purpose was to quantify the performance of the first implantable leadless cardiac monitor ( ICM ) with dedicated AF detection capabilities . Methods and Results — Patients ( n=247 ) with an implanted ICM ( Reveal XT , Medtronic Inc , Minneapolis , Minn ) who were likely to present with paroxysmal AF were selected . A special Holter device stored 46 hours of subcutaneously recorded ECG , ICM markers , and 2 surface ECG leads . The ICM  automatic arrhythmia classification was compared with the core laboratory classification of the surface ECG . Of the 206 analyzable Holter recordings collected , 76 ( 37 % ) contained at least 1 episode of core laboratory classified AF . The sensitivity , specificity , positive predictive value , and negative predictive value for identifying patients with any AF were 96.1 % , 85.4 % , 79.3 % , and 97.4 % , respectively . The AF burden measured with the ICM was very well correlated with the reference value derived from the Holter ( Pearson coefficient=0.97 ) . The overall accuracy of the ICM for detecting AF was 98.5 % . Conclusions —In this ICM validation study , the dedicated AF detection algorithm reliably detected the presence or absence of AF and the AF burden was accurately quantified . The ICM is a promising new diagnostic and monitoring tool for the clinician to treat AF patients independently of symptoms . Long-term studies are needed to evaluate the clinical benefits of the technology . Clinical Trial Registration — clinical trials.gov Identifier NCT00680927
Kardia Mobile is the most cost effective option in a full incremental analysis .
Lead-I ECG tests may identify more AF cases than the st and ard diagnostic pathway .
This comes at a higher cost but with greater patient benefit in terms of mortality and quality of life .
Conclusions The use of single-time point lead-I ECG devices in primary care for the detection of AF in people with signs or symptoms of AF and an irregular pulse appears to be a cost effective use of NHS re sources compared with MPP followed by a 12-lead ECG , given the assumptions used in the base case model .
Background Atrial fibrillation ( AF ) is the most common type of cardiac arrhythmia and is associated with increased risk of stroke and congestive heart failure .
Lead-I electrocardiogram ( ECG ) devices are h and held instruments that can detect AF at a single-time point .
Purpose To assess the diagnostic test accuracy , clinical impact and cost effectiveness of single-time point lead-I ECG devices compared with manual pulse palpation ( MPP ) followed by a 12-lead ECG for the detection of AF in symptomatic primary care patients with an irregular pulse .