SPC365

Left Ventricular Outflow Tract Obstruction During Dobutamine Stress Test Echocardiography – Predictors and Prognostic Impact

Session: SESSÃO DE POSTERS 28 - ECOCARDIOGRAFIA DE STRESS
Speaker: Simão De Almeida Carvalho

Congress: CPC 2025
Topic: B. Imaging
Theme: 03. Imaging
Subtheme: 03.1 Echocardiography
Session Type: Cartazes
FP Number: ---
Authors: Simão De Almeida Carvalho; Carlos Costa; Inês Cruz; Tiago Aguiar; Adriana Pacheco; Andreia Fernandes; Lisa Ferraz; Ana Faustino; Ana Briosa Neves
<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Introduction:</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Dynamic left ventricular outflow tract obstruction (DO) is a recognized phenomenon during dobutamine stress echocardiography (DSE), but its predictors and prognostic significance remain poorly understood.</span></span></span></p>

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<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Objective:</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">To evaluate the predictors and prognostic implications of DO during DSE.</span></span></span></p>

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<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Methods:</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Single-center retrospective study including 355 consecutive patients (P) undergoing DSE for ischemia evaluation. P were stratified into two&nbsp;groups based on the presence or absence of DO, defined as a gradient &ge;30 mmHg during DSE. Comparative analysis was performed to identify potential predictors of DO and&nbsp;P were followed for 2 years&nbsp;to evaluate 5-point MACE (defined as death, myocardial infarction, stroke, heart failure hospitalisation and urgent revascularization)</span></span><span style="color:#000000; font-family:Calibri,sans-serif">. Statistical analyses, including the&nbsp;T-Test, Chi-square, and Logistic Regression, were performed using SPSS.</span></span></p>

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

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Results:</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">A total of 355 DSE cases were analyzed, with 48 P (13.5%)&nbsp;presenting DO. The mean age was 70.3 &plusmn; 10.7 years, with 62.3% being male. Cardiovascular risk factors were present in 87.6%, with hypertension (77.5%) and dyslipidemia (60.8%) being the&nbsp;most common.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Comparative analysis showed no differences in age (70.5&plusmn;10.7 vs. 68.7&plusmn;10.4; p=0.26), hypertension prevalence (76.5% vs. 83.3%; p=0.36), diabetes (34.3% vs. 33.3%; p=1.0), dyslipidemia (60.6% vs. 62.5%; p=0.87), smoking (29.3% vs. 29.2%; p=0.72), alcohol use (10.7% vs. 8.3%; p = 0.61), or atrial fibrillation (20.5% vs. 18.8%; p=0.85). P with DO were more likely to be female (60.0% vs. 34.2%; p&lt;0.001) and less likely to have left bundle branch block (4.2% vs. 14.7%; p=0.05), chronic kidney disease (19.6% vs. 36.8%; p=0.03), or beta-blocker use (43.8% vs. 60.7%; p=0.001).</span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Echocardiographic findings showed no differences in basal septal thickness (12.0&plusmn;2.2 mm vs. 12.6&plusmn;3.0 mm; p=0.08), left atrial volume (32.9&plusmn;8.0 vs. 30.4 &plusmn; 7.4 mL/m&sup2;; p=0.23), or diastolic dysfunction (44.9% vs. 45.8%; p=0.91). However, &nbsp;P with DO had a significantly higher LVEF (63.6&plusmn;8.4% vs. 55.7&plusmn;12.7%; p&lt;0.001), fewer hypertensive responses (2.0% vs. 9.5%; p&lt;0.001), and more arrhythmias (81.3% vs. 64.1%; p=0.04).</span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px">In P with DO, there was a lower probability of a positive DSE result compared to those without DO (10.4% vs. 29.2%; p=0.02).</span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">At two years, 5-point MACE rates were similar (17.6% vs. 12.5%; p=0.38).</span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Logistic regression identified predictors of DO: female sex (HR = 2.65, CI 1.28&ndash;5.48; p=0.009), beta-blocker use (HR = 0.36, CI 0.18&ndash;0.73; p=0.005), LVEF (HR = 1.05, CI 1.01&ndash;1.09; p=0.007), and basal septal thickness (HR = 1.24, CI 1.07&ndash;1.43; p=0.004). The model&nbsp;explained 23% of the outcome variance with 79% accuracy.</span></span></span></p>

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

<p style="text-align:justify"><span style="font-size:16px"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Conclusion:</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:16px">According to this study, DO during DSE is associated with female sex, higher baseline LVEF, increased basal septal thickness, and absence of beta-blocker therapy, and has no impact on short-term prognosis.&nbsp;</span></p>