Atrial fibrillation (AF) is the most common arrhythmia, affecting an estimated 7 million people worldwide, including 4.5 million in the European Union1,2. Data presented today as a Hot Line session at the EUROPACE 2009 congress on the XPECT clinical trial, sponsored by Medtronic, Inc. (NYSE: MDT), shows that the Medtronic Reveal® XT Insertable Cardiac Monitor (ICM) reliably identifies patients with AF (sensitivity of 96.1 percent) and correctly confirms the absence of AF in patients (negative predictive value of 97.4 percent).

It is widely known that AF is an independent risk factor for stroke, increasing risk approximately five-fold3. Several recent studies have indicated that the correlation between AF episodes and symptoms is poor, meaning that patients may be symptom-free during AF, or experience AF-like symptoms not related to AF4,5.

Current methods for detecting AF, such as Holter monitors and 24-hour event monitors, have limited effectiveness, even if performed repeatedly, given the transitory nature of the monitoring6,7. XPECT (Reveal XT Performance Trial), involving 247 patients at 20 sites, was conducted to quantify the accuracy of continuous monitoring, achieved via the Reveal XT insertable cardiac monitor, for detecting and documenting AF through continuous monitoring.

Professor Gerhard Hindricks of the Heart Center at the Universitätsklinikum in Leipzig, Germany, serves as principal investigator for the XPECT trial and presented today's data. "The XPECT results show that continuous monitoring by the Reveal XT device enables reliable detection of AF with high sensitivity and specificity, along with accurate recordings of AF episode duration," said Prof. Hindricks. "Additionally, this trial demonstrated that the Reveal device correctly rules out AF in patients who do not have significant AF burden. Continuous monitoring can be an essential tool for physicians to successfully manage AF or subsequently take action to prevent negative outcomes such as stroke resulting from AF. Physicians can best optimize the use of antiarrhythmic and anticoagulation medicines only if they can precisely and correctly diagnose a patient's atrial fibrillation."

About the Reveal XT Insertable Cardiac Monitor

Placed just under the skin of the chest area in a short outpatient procedure, the Reveal XT device provides up to three years of continuous heart rhythm monitoring. Reveal XT captures and stores an electrocardiogram (ECG) automatically, according to physician-programmed settings. An additional option to store an ECG is having the patient place a hand-held pager-sized assistant over the device, and pressing a button. Later, a physician analyzes the stored information which can be transmitted remotely via the Medtronic CareLink® Network, or viewed during an in-office patient visit. Clinical data available to the physician includes views of individually stored ECG episodes, or longer-term trended diagnostic data via Reveal XT's Cardiac Compass® Report, including daily AF burden, patient activity, and average day and night heart rates. Additionally, Medtronic Reveal devices are labeled for use in MRI machines, meaning patients with a device implanted may safely undergo MRI scans under certain conditions.

"XPECT confirms the clinical utility of the Reveal XT device to identify the presence or absence of AF. In fact, it is the only device available today that has proven sensitivity and specificity detection, and monitoring capabilities for AF," said Elizabeth Hoff, general manager and vice president of the Subcutaneous Diagnostics & Monitoring unit of the Cardiac Rhythm Disease Management business at Medtronic. "Because AF puts patients at an elevated risk for stroke and can be intermittent and asymptomatic in nature, detection and continuous monitoring can provide important clinical information to guide treatment decisions."

References

1 Fuster V, et al. ACC/AHA/ESC 2006 Guidelines for the Management of Patients with Atrial Fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. Circulation. 2006;114(7):e257-354.

2 Chugh SS, Blackshear JL, Shen WK, Hammill SC, Gersh BJ. Epidemiology and natural history of atrial fibrillation: clinical implications. J Am Coll Cardiol. 2001;37(2):371-378.

3 Stroke: 1991; 22:983-988

4 M. Patten. Event-recorder monitoring in the diagnosis of atrial fibrillation in symptomatic patients: subanalysis of the SOPAT trial. JCE 2006: 17; 1216-1220

5 G. Senatore. Role of transtelephonic electrocardiographic monitoring in detecting short-term arrhythmia recurrences after radiofrequency ablation in patients with atrial fibrillation. JACC 2005; 45: 873-876

6 P. Ziegler. Comparison of continuous versus intermittent monitoring of atrial arrhythmias. Heart Rhythm 2006; 3: 1445-1452

7 H. Kottkamp. Time courses and quantitative analysis of atrial fibrillation episode number and duration after circular plus linear left atrial lesions. JACC 2004: 44; 869-877

Source
Medtronic