SPC365

Long-term outcomes in patients with potential reversible causes of bradycardia

Session: CO 11- Síncope
Speaker: Mariana Passos

Congress: CPC 2021
Topic: C. Arrhythmias and Device Therapy
Theme: 07. Syncope and Bradycardia
Subtheme: 07.4 Syncope and Bradycardia - Treatment
Session Type: Comunicações Orais
FP Number: ---
Authors: Mariana Passos; Inês Fialho; Joana Lima Lopes; Daniel Faria; João Baltazar; Marco Beringuilho; Hilaryano Ferreira; Carlos Morais; João Bicho Augusto
<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">Introduction:</span></span></strong><span style="font-size:11.0pt"><span style="font-family:Helvetica"> Hyperkalemia and </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">negative chronotropic</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica"> drugs are well known causes of reversible bradycardia. Their synergic combination may result in BRASH syndrome (<strong>B</strong>radycardia, <strong>R</strong>enal failure, </span></span><strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">A</span></span></strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">trioventricular</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica"> blockade, <strong>S</strong>hock, and <strong>H</strong>yperkalemia), a consequence of the vicious cycle between bradycardia, renal failure and worsening hyperkalemia, leading ultimately to multiorgan dysfunction. In potentially reversible bradycardia, drug discontinuation or metabolic correction is recommended before permanent pacemaker (PPM) implantation.</span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">Objectives: </span></span></strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">To determine the long-term prognosis in patients with potentially reversible symptomatic bradycardia.</span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">Methods: </span></span></strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">We retrospectively reviewed 176 patients who presented to the emergency department with symptomatic bradycardia, between January 2015 and August 2016. Patients without any reversible cause of bradycardia were excluded. Participants were stratified into three groups according to the reversible causes of bradycardia:&nbsp;patients with hyperkalemia, with or without acute renal injury (ARI) (group 1); patients taking negative chronotropic drugs, with or without ARI (group 2);&nbsp;patients with </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">BRASH syndrome (</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">combination of </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">hyperkalemia and </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">negative chronotropic drugs, </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">with or without ARI) (group 3). The primary endpoint was PPM implantation after discharge. S<span style="color:black">econdary endpoints included: bradycardia-related rehospitalization, heart failure (HF) </span>hospitalization<span style="color:black">, all-cause mortality </span>and a composite <span style="color:black">of all the previous endpoints. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">Results:</span></span></strong><span style="font-size:11.0pt"><span style="font-family:Helvetica"> A total of 105 patients were included (52.4% female; mean age 79.8&plusmn;8.6 years). Group 1 was comprised by&nbsp;</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">15 patients&nbsp;(14.3%)</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">, group 2 by&nbsp;</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">69 patients (65.7%) and group 3 by 21 patients (20%, figure 1A). The incidence of each event is presented in figure 1B.&nbsp; During a mean follow-up of 3.2&plusmn;2.1 years, PPM was implanted in 60 patients (57.1%) &ndash; 51 during hospital stay (85%) and 9 after discharge (15%). Across all groups, approximately 50% of the patients needed PPM implantation at some point, without significant differences between groups (p=0.508). Group 3 had the lowest need of in-hospital PPM (38.1%) but the highest </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">bradycardia-related readmissions (9.5%). Nevertheless, </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">p</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">ost-discharge PPM implantation</span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica"> was still higher in group 1 (33.3%), followed by group 3 (22.2%). There were no significant differences in the post-discharge PPM implantation rate between groups (p=0.76). </span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica"><span style="color:black">In groups 1 and 3 the composite endpoint (73.3% and 76.2%, respectively) </span></span></span><span style="font-size:11.0pt"><span style="font-family:Helvetica">was significantly more frequent than in group 2 (44.9%, p=0.046 and p=0.012, respectively).</span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">Conclusions: </span></span></strong><span style="font-size:11.0pt"><span style="font-family:Helvetica">Nearly half of the patients with an episode of reversible bradycardia needed a PPM at some point. Given the advanced age of most patients with bradycardia secondary to metabolic derangement and/or drug toxicity, it is possible that this unveils underlying conduction system disease, which is likely to recur without PPM implantation. </span></span></span></span></p>