AUTHOR=Jøns Christian , Bloch Thomsen Poul Erik , Riahi Sam , Smilde Tom , Bach Ulrich , Jacobsen Peter Karl , Táborský Miloš , Faluközy Jozsef , Wiemer Marcus , Christensen Per Dahl , Kónyi Attila , Schelfaut Dan , Bulava Alan , Grabowski Marcin , Merkely Béla , Nuyens Dieter , Mahajan Rajiv , Nagel Patrick , Tilz Roland , Malczynski Jerzy , Steinwender Clemens , Brachmann Johannes , Serota Harvey , Schrader Jürgen , Behrens Steffen , Søgaard Peter 

TITLE=Arrhythmia monitoring and outcome after myocardial infarction (BIO|GUARD-MI): a randomized trial

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=11

YEAR=2024

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2024.1300074

DOI=10.3389/fcvm.2024.1300074

ISSN=2297-055X

ABSTRACT=<sec><title>Objectives</title><p>Cardiac arrhythmias predict poor outcome after myocardial infarction (MI). We studied if arrhythmia monitoring with an insertable cardiac monitor (ICM) can improve treatment and outcome.</p></sec><sec><title>Design</title><p>BIO|GUARD-MI was a randomized, international open-label study with blinded outcome assessment.</p></sec><sec><title>Setting</title><p>Tertiary care facilities monitored the arrhythmias, while the follow-up remained with primary care physicians.</p></sec><sec><title>Participants</title><p>Patients after ST-elevation (STEMI) or non-ST-elevation MI with an ejection fraction &gt;35% and a CHA<sub>2</sub>DS<sub>2</sub>-VASc score ≥4 (men) or ≥5 (women).</p></sec><sec><title>Interventions</title><p>Patients were randomly assigned to receive or not receive an ICM in addition to standard post-MI treatment. Device-detected arrhythmias triggered immediate guideline recommended therapy changes via remote monitoring.</p></sec><sec><title>Main outcome measures</title><p>MACE, defined as a composite of cardiovascular death or acute unscheduled hospitalization for cardiovascular causes.</p></sec><sec><title>Results</title><p>790 patients (mean age 71 years, 72% male, 51% non-STEMI) of planned 1,400 pts were enrolled and followed for a median of 31.6 months. At 2 years, 39.4% of the device group and 6.7% of the control group had their therapy adapted for an arrhythmia [hazard ratio (HR) = 5.9, <italic>P</italic> &lt; 0.0001]. Most frequent arrhythmias were atrial fibrillation, pauses and bradycardia. The use of an ICM did not improve outcome in the entire cohort (HR = 0.84, 95%-CI: 0.65–1.10; <italic>P</italic> = 0.21). In secondary analysis, a statistically significant interaction of the type of infarction suggests a benefit in the pre-specified non-STEMI subgroup. Risk factor analysis indicates that this may be connected to the higher incidence of MACE in patients with non-STEMI.</p></sec><sec><title>Conclusions</title><p>The burden of asymptomatic but actionable arrhythmias is large in post-infarction patients. However, arrhythmia monitoring with an ICM did not improve outcome in the entire cohort. Post-hoc analysis suggests that it may be beneficial in non-STEMI patients or other high-risk subgroups.
</p></sec><sec><title>Clinical Trial Registration</title><p>[<ext-link ext-link-type="uri" xlink:href="https://www.clinicaltrials.gov/ct2/show/NCT02341534" xmlns:xlink="http://www.w3.org/1999/xlink">https://www.clinicaltrials.gov/ct2/show/NCT02341534</ext-link>], NCT02341534.</p></sec>