title: Cardiac rehabilitation after acute coronary syndrome: Do all patients derive the same benefit?
abstract: BACKGROUND
  Cardiac rehabilitation (CR) has been demonstrated to improve exercise capacity in acute coronary syndrome (ACS), but not all patients derive the same benefit. Careful patient selection is crucial to maximize resources.
  
  
  OBJECTIVE
  To identify in a heterogeneous ACS population which patients would benefit the most with CR, in terms of functional capacity (FC), by using cardiopulmonary exercise testing (CPET).
  
  
  METHODS
  A retrospective analysis of consecutive ACS patients who underwent CR and CPET was undertaken. CPET was performed at baseline and after 36 sessions of exercise. Peak oxygen uptake (pVO2), percentage of predicted pVO2, minute ventilation/CO2production (VE/VCO2) slope, VE/VCO2slope/pVO2and peak circulatory power (PCP) (pVO2times peak systolic blood pressure) were assessed in two moments. The differences in pVO2(ΔpVO2), %pVO2, PCP and exercise test duration were calculated. Patients were classified according to baseline pVO2(group 1, <20 ml/kg/min vs. group 2, ≥20 ml/kg/min) and left ventricular ejection fraction (group A, <50% vs. group B, ≥50%).
  
  
  RESULTS
  We analyzed 129 patients, 86% male, mean age 56.3±9.8 years. Both group 1 (n=31) and group 2 (n=98) showed significant improvement in FC after CR, with a more significant increase in pVO2, in group 1 (ΔpVO24.4±7.3 vs. 1.6±5.4; p=0.018). Significant improvement was observed in CPET parameters in group A (n=34) and group B (n=95), particularly in pVO2and test duration.
  
  
  CONCLUSIONS
  Patients with lower baseline pVO2(<20 ml/kg/min) presented more significant improvement in FC after CR. CPET which is not routinely used in assessement before CR in context of ACS, could be a valuable tool to identify patients who will benefit the most.
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal. Electronic address: silviaguiarosa@gmail.com.
authors.forename: Sílvia
authors.initials: S
authors.lastname: Aguiar Rosa
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Abreu
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Marques Soares
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Rio
authors.affiliation: Department of Physiatry, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Custódia
authors.initials: C
authors.lastname: Filipe
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Inês
authors.initials: I
authors.lastname: Rodrigues
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: André
authors.initials: A
authors.lastname: Monteiro
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Soares
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Vítor
authors.initials: V
authors.lastname: Ferreira
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Sofia
authors.initials: S
authors.lastname: Silva
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Sandra
authors.initials: S
authors.lastname: Alves
authors.affiliation: Department of Cardiology, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Cruz Ferreira
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis / Q000503:physiopathology / Q000534:rehabilitation*; D000072038:Cardiac Rehabilitation; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Acute coronary syndrome; Cardiac rehabilitation; Cardiopulmonary exercise testing; Prova de esforço cardiorrespiratória; Reabilitação cardíaca; Síndrome coronária aguda