QT interval and short-term outcome in acute heart failure
Authors: Miró Òscar , Aguiló Oriol , Trullàs Joan Carles , Gil Víctor , Espinosa Begoña , Jacob Javier , Herrero-Puente Pablo , Tost Josep , López-Grima María Luísa , Comas Pere , Bibiano Carlos , Llauger Lluís , Martin Mojarro Enrique , López-Díez María Pilar , Núñez Julio , Rafique Zubaid , Keene Kelly R. , Peacock Frank , Lopez-Ayala Pedro , Mueller Christian , Montero Pérez-Barquero Manuel , Mont Lluís , Llorens Pere ,   the ICA-SEMES research investigators, Fuentes Marta , Gil Cristina , Alonso Héctor , Pérez-Llantada Enrique , Martín-Sánchez Francisco Javier , Llopis García Guillermo , Cadenas Mar Suárez , Escoda Rosa , Aguiló Sira , Sánchez Carolina , Millán Javier , Pavón José , Noval Antonio , López-Grima María Luisa , Valero Amparo , Juan María Ángeles , Aguirre Alfons , Pedragosa Maria Àngels , Mínguez Masó Silvia , Alonso María Isabel , Ruiz Francisco , Franco José Miguel , Mecina Ana Belén , Berenguer Marta , Donea Ruxandra , Sánchez Ramón Susana , Carbajosa Rodríguez Virginia , Piñera Pascual , Sánchez Nicolás José Andrés , Torres Garate Raquel , Alquézar-Arbé Aitor , Rizzi Miguel Alberto , Herrera Sergio , Roset Alex , Cabello Irene , Haro Antonio , Richard Fernando , Álvarez Pérez José María , Herrero Puente Pablo , Vázquez Álvarez Joaquín , Prieto García Belén , García García María , Sánchez González Marta , Javaloyes Patricia , Jiménez Inmaculada , Hernández Néstor , Gil Adriana , Molina Francisca , García Tamara , Andueza Juan Antonio , Romero Rodolfo , Ruíz Martín , Calvache Roberto , Lorca Serralta María Teresa , Calderón Jave Luis Ernesto , Amores Arriaga Beatriz , Sierra Bergua Beatriz , Martín Mojarro Enrique , Alarcón Jiménez Brigitte Silvana , Travería Bécquer Lisette , Burillo Guillermo , Llauger García Lluís , Corominas LaSalle Gerard , Agüera Urbano Carmen , García Soto Ana Belén , Delgado Padial Elisa , Soy Ferrer Ester , Adroher Múñoz María , Garrido José Manuel , Lucas-Imbernón Francisco Javier , Gaya Rut , Bibiano Carlos , Mir María , Rodríguez Beatriz , Carballo José Luis , Rodríguez-Adrada Esther , Rodríguez Miranda Belén , Vicente Martín Monika , Coma Casanova Pere , Espinach Alvarós Joan 
Published: April 2023

Abstract
Objective
To investigate the association of corrected QT (QTc) interval duration and short-term outcomes in patients with acute heart failure (AHF).

Methods
We analyzed AHF patients enrolled in 11 Spanish emergency departments (ED) for whom an ECG with QTc measurement was available. Patients with pace-maker rhythm were excluded. Primary outcome was 30-day all-cause mortality and secondary outcomes were need of hospitalization, in-hospital mortality and prolonged hospitalization (> 7 days). Association between QTc and outcomes was explored by restricted cubic spline (RCS) curves. Results were expressed as odds ratios (OR) and 95%CI adjusted by patients baseline and decompensation characteristics, using a QTc = 450 ms as reference.

Results
Of 1800 patients meeting entry criteria (median age 84 years (IQR = 77–89), 56% female), their median QTc was 453 ms (IQR = 422–483). The 30-day mortality was 9.7%, while need of hospitalization, in-hospital mortality and prolonged hospitalization were 77.8%, 9.0% and 50.0%, respectively. RCS curves found longer QTc was associated with 30-day mortality if > 561 ms, OR = 1.86 (1.00–3.45), and increased up to OR = 10.5 (2.25–49.1), for QTc = 674 ms. A similar pattern was observed for in-hospital mortality; OR = 2.64 (1.04–6.69), for QTc = 588 ms, and increasing up to OR = 8.02 (1.30–49.3), for QTc = 674 ms. Conversely, the need of hospitalization had a U-shaped relationship: being increased in patients with shorter QTc [OR = 1.45 (1.00–2.09) for QTc = 381 ms, OR = 5.88 (1.25–27.6) for the shortest QTc of 200 ms], and also increasing for prolonged QTc [OR = 1.06 (1.00–1.13), for QTc = 459 ms, and reaching OR = 2.15 (1.00–4.62) for QTc = 588 ms]. QTc was not associated with prolonged hospitalization.

Conclusion
In ED AHF patients, initial QTc provides independent short-term prognostic information, with increasing QTc associated with increasing mortality, while both, shortened and prolonged QTc are associated with need of hospitalization.

Graphical abstract