SPC365

Symptom-Rhythm Correlation of Implantable Loop Recorders in Patients with Syncope/Presyncope

Session: Sessão de Posters 43 - Inovações em Síncope e Pacing Cardíaco
Speaker: ANGELA MARGARIDA MARTINS DE CASTRO

Congress: CPC 2024
Topic: C. Arrhythmias and Device Therapy
Theme: 09. Device Therapy
Subtheme: 09.6 Device Therapy - Other
Session Type: Cartazes
FP Number: ---
Authors: Margarida De Castro; Mariana Tinoco; Luísa Pinheiro; Cláudia Mendes; Assunção Alves; Bernardete Rodrigues; Ana Rita Andrade; Lucy Calvo; Sílvia Ribeiro; João Português; Victor Sanfins; António Lourenço

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><strong><span style="font-family:&quot;Calibri&quot;,sans-serif">INTRODUCTION:</span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif"> Implantable loop recorders (ILRs) are a powerful diagnostic tool for heart rhythm disorders, particularly when symptoms are infrequent and long-term monitoring is needed to establish a diagnosis. They are primarily indicated for studying syncope and presyncope cases suspected to have a cardiac etiology.</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-family:&quot;Calibri&quot;,sans-serif">OBJECTIVE:</span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif"> To evaluate the correlation between symptoms and heart rhythm disorders during follow-up (FU). </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-family:&quot;Calibri&quot;,sans-serif">METHODS:</span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif"> Retrospective study conducted at a single center including patients (P) who underwent ILR implantation for evaluation of unexplained syncope or presyncope between 2000 and 2023. </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="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black">RESULTS:</span></span></span></strong><span style="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black"> We included 540P (91%) with syncope and 55P (9%) with presyncope. The mean age was 68&plusmn;14 years and 50% were female. Median follow-up was 21 (IQR 7-38) months.</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"><span style="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black">ILR results led to device implantation in 33% of the P (88% pacemaker, 9% ICD, 3% CRT), with a median time to implantation of </span></span></span><span style="font-family:&quot;Calibri&quot;,sans-serif">6 (IQR 2-14) months<span style="background-color:white"><span style="color:black"> after ILR. From these, the majority of ILR implantation was motivated by syncope (88%). The most common arrhythmic findings were sick sinus syndrome in 101P (52%), followed by advanced AV block (AVB) in 66P (34%), ventricular tachycardia in 14P (7%), and atrial fibrillation with slow ventricular rate in 13P (7%). </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"><span style="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black">During FU, 205P (35%) experienced symptoms (92% with syncope/presyncope and 8% with palpitations), with 180P (88%) achieving symptom-rhythm correlation. </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"><span style="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black">Comparing the 25P (8%) who presented symptoms without ECG correlation to P who underwent device implantation, the 1st group was younger (mean age 65&plusmn;12 vs 74&plusmn;11 years<em>, p=</em>0.001), had a higher prevalence of smoking (28% vs 11%, <em>p=</em>0.031), and a lower incidence of heart conduction disorders (12% vs 46%, <em>p=</em>0.002). They also had a lower incidence of 1<sup>st</sup> AVB (0% vs 20%) and left bundle branch block (0% vs 14%).</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="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black">CONCLUSION: </span></span></span></strong><span style="background-color:white"><span style="font-family:&quot;Calibri&quot;,sans-serif"><span style="color:black">Implantable loop recorders have proven to be valuable in evaluating cases of syncope/presyncope and establishing a correlation between symptoms and heart rhythm patterns. This correlation has led to the recommendation of appropriate device implantation. It was observed that patients who presented symptoms without ECG correlation were younger and had a lower incidence of heart conduction disorders. These findings highlight potential differences in patient characteristics and underlying pathophysiology. Further research is needed to optimize the use of ILRs and improve diagnostic outcomes in this population.</span></span></span></span></span></p>