SPC365

What is the long-term prognosis of acute myocarditis? Results of a long-term prospective study

Session: Sessão de Posters 11 - Miocardite Aguda
Speaker: Marta Miguez Vilela

Congress: CPC 2024
Topic: F. Valvular, Myocardial, Pericardial, Pulmonary, Congenital Heart Disease
Theme: 17. Myocardial Disease
Subtheme: 17.4 Myocardial Disease – Treatment
Session Type: Cartazes
FP Number: ---
Authors: Marta Miguez De Freitas Vilela; Ana Margarida Martins; Ana Beatriz Garcia; Catarina Simões de Oliveira; Miguel Nobre Menezes; João Silva Marques; Beatriz Silva; Joana Rigueira; Rui Plácido; Dulce Brito; Ana G Almeida; Fausto J. Pinto
<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><strong><span style="color:black">Introduction:</span></strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">In patients (pts) with acute myocarditis, guidelines advocate annual follow-up (FUP), including ECG and echocardiogram for at least four years. Nevertheless, few contemporary prospective studies have addressed the long-term prognosis of acute myocarditis, rendering the best strategy for the FUP of these pts ill-supported by evidence.</span></span></span></span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><strong><span style="color:black">Purpose</span></strong><span style="color:black">:&nbsp;</span><span style="font-size:12pt"><span style="color:black">To assess long-term outcomes of acute myocarditis pts.</span></span></span></span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><strong><span style="color:black">Methods:&nbsp;</span></strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">Prospective observational single-center study including pts admitted with acute myocarditis from 2007 to 2022 and followed at a tertiary cardiology center. Clinical, imaging and laboratory data was collected. Pts were followed for a </span></span><span style="font-size:12pt">minimum<span style="color:black"> of five years with annual clinical, treadmill, Holter and transthoracic echocardiogram. After that period, they chose to either continue FUP or be discharged. Pts who were discharged received a telephone FUP during November 2023. Frequency tables were </span>obtained<span style="color:black"> and data analysis was performed with Chi-square test and Cox regression.</span></span></span></span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><strong><span style="color:black">Results:&nbsp;</span></strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">We included 158 pts, 12.7% female, with a mean age of 33&plusmn;13 years.&nbsp; The majority presented with chest pain (94.3%). Seven pts (3,6%) had severe complications, such as cardiogenic shock or arrhythmic storm. Upon admission, 44.3% of pts showed ST-segment elevation&nbsp;and a mean left ventricle ejection fraction (LVEF) of 58&plusmn;7.8%. Out of the 140 pts who underwent cardiac magnetic resonance imaging (CMR), myocardial edema and late gadolinium enhancement (LGE) were present in 47.8% and 88.5%, respectively. Myocardial biopsy was performed in 9 pts.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">During a mean FUP time of 6&plusmn;4,3 years only 13,3% pts were readmitted, 80,9% of them due to recurrent myocarditis. Only 1 pts with LVEF&lt;50% at admission did not recover at FUP. All other pts maintained LVEF&gt;50% at FUP. No pts exhibited significant arrythmias on holter monitoring or during treadmil stress tests.&nbsp;</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">Severe complications during admission did not correlate with reduced LVEF at one year (p=0,20) or at FUP (p =0,08). FUP CMR was conducted on 63 pts, with 4.8% of them retaining myocardial edema and 73.1% LGE.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">Six pts (3,8%) died at FUP. Four pts had </span></span><span style="font-size:12pt">experienced<span style="color:black"> fulminant myocarditis at index admission and died due to recurrent fulminant myocarditis. One pts died 6 years after uncomplicated acute myocarditis due to non CV-causes, at age 62. One pts died 2 years after non-complicated acute myocarditis due to trauma. There was a statistically significant association between death and severe complications during index admission (p&lt;0,001).</span></span></span></span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><strong><span style="font-size:12pt"><span style="color:black">Conclusion:&nbsp;</span></span></strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Arial,sans-serif"><span style="color:#000000"><span style="font-size:12pt"><span style="color:black">Myocarditis affects a young population and the majority of patients exhibit a benign course at long-term FUP. Pts with fulminant myocarditis had a poor prognosis even after index-event survival, often due to recurrent fulminant myocarditis. Thus, early disease stages seem to determine prognosis, prompting consideration of whether pts with milder cases truly require extended FUP.</span></span></span></span></span></p>