SPC365

Fast Italian versus Front-Loaded Tilt Protocols in Unexplained Syncope: A Single-Centre Retrospective Comparison

Session: Sessão de Posters 58 - Otimizar os cuidados cardiovasculares: perspetivas de enfermagem e de técnicos de cardiopneumologia
Speaker: Helena Fonseca

Congress: CPC 2026
Topic: C. Arrhythmias and Device Therapy
Theme: 07. Syncope and Bradycardia
Subtheme: 07.3 Syncope and Bradycardia - Diagnostic Methods
Session Type: Posters Eletrónicos
FP Number: ---
Authors: Helena Fonseca; Raquel Moreira; Sara Laginha; Rita Contins; Cátia Guerra; Helder Santos; Ana Lousinha; Sérgio Laranjo; Mário Oliveira

<p><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Introduction</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Head-up tilt testing (HUTT) remains the cornerstone of vasovagal syncope diagnosis, yet the optimal protocol balancing diagnostic yield, patient comfort, and laboratory efficiency is still debated. Accelerated protocols&mdash;namely the Fast Italian (FI) and Front-Loaded (FL)&mdash;have emerged as practical alternatives to the traditional Westminster protocol. However, direct comparative data are scarce, limiting evidence-based protocol selection.</span></span></span></p>

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<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Aim</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">To compare the diagnostic yield and haemodynamic phenotype distribution of the FI and FL tilt protocols in patients referred for unexplained syncope, and to characterise the demographic profile and additional autonomic findings associated with each approach.</span></span></span></p>

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<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Methods</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">We performed a retrospective analysis of 234 consecutive patients undergoing HUTT for unexplained syncope over a 12-month period (FI n=116; FL n=118). Protocol assignment was determined by temporal period. Demographic data, tilt outcomes (classified according to the modified VASIS classification), and additional autonomic findings&mdash;including orthostatic hypotension (OH) and dysautonomia&mdash;were extracted from standardised medical records. Group comparisons employed chi-square tests for categorical variables and independent-samples t-tests for continuous variables, with statistical significance set at p&lt;0.05.</span></span></span></p>

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<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Results</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">The FI cohort was significantly older (64.9&plusmn;20.3 vs 48.9&plusmn;21.2 years; p&lt;0.001) and comprised a higher proportion of males (69.8% vs 54.2%; p=0.020) compared with the FL group. Despite these demographic differences, overall positivity rates did not differ significantly between protocols (FI 74.1% vs FL 67.8%; p=0.36). The distribution of vasovagal subtypes among positive tests did not differ significantly between protocols (p=0.052), although a numerical trend towards more Type 3 (vasodepressor) responses was observed in the FI group (35.3% vs 21.2%; p=0.058, Fisher&#39;s exact test). Notably, orthostatic hypotension (15 cases: 10 classical OH, 5 initial OH) and dysautonomia (1 case) were identified exclusively in the FI cohort, reflecting the structural absence of a passive standing phase in the FL protocol.</span></span></span></p>

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<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Conclusion</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Both accelerated tilt protocols achieved comparable overall diagnostic yields for vasovagal syncope, though direct comparison is limited by significant baseline demographic differences between cohorts. The FL protocol offers shorter procedure duration but inherently cannot detect orthostatic hypotension or other passive-phase abnormalities due to the omission of the initial supine-to-standing transition. Protocol selection should therefore be guided not only by logistical considerations but also by the pre-test clinical suspicion for orthostatic intolerance. Prospective studies with matched populations are warranted to validate these findings and refine protocol selection criteria.</span></span></span></p>