title: Functional parameters but not heart rate variability correlate with long-term outcomes in St-elevation myocardial infarction patients treated by primary angioplasty.
abstract: BACKGROUND
  Depressed heart rate variability (HRV) is usually considered a negative long-term prognostic factor after acute myocardial infarction. Anyway, most of the supporting research was conducted before the era of immediate reperfusion by percutaneous coronary intervention (PCI). Main aim of this study was to evaluate if HRV still retains prognostic significance in our era of immediate PCI.
  
  
  RESULTS
  Two weeks after STEMI treated by primary PCI, time-domain HRV was assessed from 24-h Holter recordings in 186 patients: markedly depressed HRV (SDNN <70ms or <50ms) was present in 16% and in 5% of cases, respectively; patients with left ventricle ejection fraction (LVEF) <40% presented more often SDNN values in the lowest quartile. Physical performance was also assessed, by 6-minute walk tests (6MWT) and by cardiopulmonary exercise test (CPET). After >2years from infarction, occurrence of major clinical events (MCE) was investigated. Cases with or without MCE did not differ by initial HRV parameters; Kaplan-Meier events-free survival curves were similar between patients with lowest quartile SDNN and the remaining ones (χ20.981, p=0.322). By the contrary, events-free survival was worse if patients walked shorter distances at 6MWT (χ26.435, p=0.011), developed poorer ventilatory efficiency at CPET (χ210.060, p=0.002), or presented LVEF <40% (χ27.085, p=0.008).
  
  
  CONCLUSIONS
  In primary-PCI STEMI patients, markedly abnormal HRV was found in a small percentage of cases. HRV seems to have lost its prognostic significance, while parameters indicating LV function (LVEF and physical performance) could allow better prognostication in primary-PCI STEMI patients.
authors.affiliation: Preventive Cardiology and Rehabilitation, Inst. Codivilla-Putti, Cortina d'Ampezzo (BL), Italy; Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy. Electronic address: L.compostella@alice.it.
authors.forename: Leonida
authors.initials: L
authors.lastname: Compostella
authors.affiliation: Dpt Cardiology, Krapinske Toplice Hospital for Medical Rehabilitation, Krapinske Toplice, Croatia; Faculty of Medicine, J. J. Strossmayer University of Osijek, Osijek, Croatia.
authors.forename: Nenad
authors.initials: N
authors.lastname: Lakusic
authors.affiliation: Preventive Cardiology and Rehabilitation, Inst. Codivilla-Putti, Cortina d'Ampezzo (BL), Italy; Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Russo
authors.affiliation: Preventive Cardiology and Rehabilitation, Inst. Codivilla-Putti, Cortina d'Ampezzo (BL), Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Setzu
authors.affiliation: Dpt Medicine, School of Emergency Medicine, University of Padua, Padova, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Compostella
authors.affiliation: Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.
authors.forename: Elia
authors.initials: E
authors.lastname: Vettore
authors.affiliation: Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.
authors.forename: Giambattista
authors.initials: G
authors.lastname: Isabella
authors.affiliation: Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Tarantini
authors.affiliation: Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.
authors.forename: Sabino
authors.initials: S
authors.lastname: Iliceto
authors.affiliation: Preventive Cardiology and Rehabilitation, Inst. Codivilla-Putti, Cortina d'Ampezzo (BL), Italy; Dpt Cardiac, Thoracic and Vascular Sciences, University of Padua, Padova, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Bellotto
mesh_terms: D000368:Aged; D018572:Disease-Free Survival; D015716:Electrocardiography, Ambulatory / Q000379:methods; D005080:Exercise Test / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D000069451:Long Term Adverse Effects / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects* / Q000379:methods; D010807:Physical Endurance / Q000502:physiology*; D011379:Prognosis; D020127:Recovery of Function / Q000502:physiology*; D012189:Retrospective Studies; D000072657:ST Elevation Myocardial Infarction / Q000175:diagnosis / Q000503:physiopathology / Q000534:rehabilitation / Q000601:surgery; D013223:Statistics as Topic; D000070857:Walk Test / Q000379:methods
keywords: Cardiopulmonary exercise test; Heart rate variability; Myocardial infarction; Physical fitness; Primary percutaneous coronary intervention; Prognosis