title: Prognostic role of stress/rest myocardial perfusion scintigraphy in patients with cardiac syndrome x.
abstract: OBJECTIVE
  The prognostic utility of myocardial perfusion scintigraphy (MPS) in patients with angiographically normal coronary arteries has not been evaluated yet. Our aim was to determine the prognostic role of positive MPS in patients with angina, positive exercise test and smooth coronary arteries (syndrome X).
  
  
  METHODS
  A total of 156 patients with angina, positive exercise test, positive MPS and normal coronary arteries and 172 patients with angina and positive exercise test who had negative MPS were selected for study. The primary endpoint was combined all-cause mortality and hospitalizations for cardiac causes. The secondary endpoint was hospitalization for cardiac causes.
  
  
  RESULTS
  Kaplan-Meier analysis showed a greater (p=0.001) incidence of the primary endpoint in patients with positive MPS, compared to those with negative MPS. Additionally, Kaplan-Meier analysis for cardiovascular hospitalization showed a significant difference (p=0.003) between the two groups. Cox regression analysis, adjusted for age, sex, BMI and antianginal therapy confirmed a significant risk increase for patients with positive MPS, with a hazard ratio (HR)=3.20 (CI 95%: 1.14-9.02; p=0.028). Cox analysis for cardiovascular hospitalization also showed a significant risk increase for patients with positive MPS (HR=3.19; CI 95%: 1.13-9.00; p=0.03). Finally, Cox analysis showed that patients with positive MPS tend to have a higher risk to remain symptomatic in the follow-up period (HR=1.614; CI 95%: 0.999-2.607; p=0.51).
  
  
  CONCLUSIONS
  This study shows that inducible myocardial hypoperfusion at MPS in patients with syndrome X could discriminate patients with a more severe prognosis, especially in terms of further hospitalization and symptomatic burden.
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy. Electronic address: gabriele.fragasso@hsr.it.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Fragasso
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Ludovica
authors.initials: L
authors.lastname: Lauretta
authors.affiliation: Department of Nuclear Medicine, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Busnardo
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Cera
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Cosmo
authors.initials: C
authors.lastname: Godino
authors.affiliation: Interventional Cardiology Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Colombo
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Giliola
authors.initials: G
authors.lastname: Calori
authors.affiliation: Department of Nuclear Medicine, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Todeschini
authors.affiliation: Department of Nuclear Medicine, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Spinapolice
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Cappelletti
authors.affiliation: Department of Nuclear Medicine, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Gianolli
authors.affiliation: Clinical Cardiology, Heart Failure Unit, Istituto Scientifico San Raffaele, Milano, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Margonato
mesh_terms: D000368:Aged; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000639:trends; D006801:Humans; D008297:Male; D017566:Microvascular Angina / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods* / Q000639:trends; D011379:Prognosis; D012146:Rest / Q000502:physiology*
keywords: Cardiac syndrome X; Myocardial perfusion scintigraphy; Normal coronary arteries; Prognosis; SPECT