SPC365

QRS width variation as a marker of prognosis after CRT implantation: getting slimmer is getting better!

Session: Posters (Sessão 4 - Écran 1) - Dispositivos em Arritmologia
Speaker: Ana Margarida Martins

Congress: CPC 2023
Topic: C. Arrhythmias and Device Therapy
Theme: 09. Device Therapy
Subtheme: 09.6 Device Therapy - Other
Session Type: Pósters Electrónicos
FP Number: ---
Authors: Ana Margarida Martins; Joana Brito; Pedro Silvério António; Sara Coto Pereira; Inês Aguiar Ricardo; Pedro Alves da Silva; Beatriz Valente Silva; Catarina Oliveira; Beatriz Garcia; Ana Abrantes; Miguel Raposo; Catarina Gregório; João Fonseca; Ana Bernardes; João Tiago; Andreia Magalhães; Fausto J. Pinto; João de Sousa; Pedro Marques

<p style="text-align:start"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">Introduction: </span></span></strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">Cardiac resynchronization therapy (CRT) is a major therapeutic tool in the management of patients with systolic heart failure. &nbsp;<span style="color:black"><span style="background-color:white">However, controversy remains regarding who will most benefit from this device. The aim of the present study was to evaluate the impact of QRS duration on echocardiographic response and clinical outcomes. </span></span></span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif"><span style="color:black"><span style="background-color:white">Methods: </span></span></span></span></strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif"><span style="color:black"><span style="background-color:white">We conducted a retrospective, observational, single-center study of patients submitted to CRT implantation. Only patients with electro and echocardiographic data on baseline and follow-up were included.</span></span></span></span> <span style="font-size:10pt"><span style="font-family:Calibri,sans-serif"><span style="color:black"><span style="background-color:white">CRT response was defined as an improvement of LVEF &gt;10% or LVESV&gt;5%. CRT superresponse was defined as an improvement of LVEF above the population 4<sup>th</sup> quartile (18%). </span></span></span></span><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">Impact of QRS variables on CRT response was evaluated with ROC curve analysis<span style="color:black"><span style="background-color:white">. Clinical outcomes were defined as hospitalizations due to heart failure and all-cause mortality. Impact of QRS on clinical endpoints, response and superresponse was evaluated with survival analysis.</span></span></span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">Results: </span></span></strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">From a total of 654 pts a total of 245 fulfilled the inclusion criteria. (57,3%% female, mean age). Most of the pts had a non-ischemic etiology (61,5%) and atrial fibrillation was present in 29.4%. The QRS characteristic were the following, baseline: 162+21ms, follow-up 159+28ms, mean QRS variation: 3+29ms. CRT response occurred in 69% of the pts and superresponse in 26%. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">QRS variation is the best predictor of CRT response (AUC =0,66, 95%CI 0,58-0,74, p&lt;0,001). Interestingly, a QRS reduction above 8ms presented the best accuracy (S:70%; E:57%) for response to CRT.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">On multivariate analysis, after adjustment for gender, atrial fibrillation and cardiopathy etiology, only a QRS reduction above 8ms (p 0.028, HR 1.974 CI (1.075-3.623) and lower baseline LVEF (p = 0.02, 95% CI 0.943 (0.909-0.979) were significant independent predictors of CRT superresponse.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif">Additionally, a QRS reduction higher than 8ms was a protective factor for long-term clinical outcomes during follow-up (p&lt;0.001 HR (2,445) 1,553 a 3,849) &ndash; fig.1.</span></span></span></span></span></p>

<p style="text-align:start"><span style="font-size:medium"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="color:#000000"><strong><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif"><span style="color:black"><span style="background-color:white">Conclusion: </span></span></span></span></strong></span></span></span></p>

<p><span style="font-size:10pt"><span style="font-family:Calibri,sans-serif"><span style="color:black"><span style="background-color:white">In pts with implanted CRT a reduction in QRS width, as small as 8ms, its a marker of improved LV function and a better clinical prognosis.</span></span></span></span></p>