title: Cardiopulmonary exercise test and sudden cardiac death risk in hypertrophic cardiomyopathy.
abstract: BACKGROUND
  In hypertrophic cardiomyopathy (HCM), most of the factors associated with the risk of sudden cardiac death (SCD) are also involved in the pathophysiology of exercise limitation. The present multicentre study investigated possible ability of cardiopulmonary exercise test in improving contemporary strategies for SCD risk stratification.
  
  
  METHODS
  A total of 623 consecutive outpatients with HCM, from five tertiary Italian HCM centres, were recruited and prospectively followed, between September 2007 and April 2015. The study composite end point was SCD, aborted SCD and appropriate implantable cardioverter defibrillator (ICD) interventions.
  
  
  RESULTS
  During a median follow-up of 3.7 years (25th-75th centile: 2.2-5.1 years), 25 patients reached the end point at 5 years (3 SCD, 4 aborted SCD, 18 appropriate ICD interventions). At multivariate analysis, ventilation versus carbon dioxide relation during exercise (VE/VCO2 slope) remains independently associated to the study end point either when challenged with the 2011 American College of Cardiology Foundation/American Heart Association guidelines-derived score (C index 0.748) or with the 2014 European Society of Cardiology guidelines-derived score (C index 0.750). A VE/VCO2 slope cut-off value of 31 showed the best accuracy in predicting the SCD end point within the entire HCM study cohort (sensitivity 64%, specificity 72%, area under the curve 0.72).
  
  
  CONCLUSIONS
  Our data suggest that the VE/VCO2 slope might improve SCD risk stratification, particularly in those HCM categories classified at low-intermediate SCD risk according to contemporary guidelines. There is a need for further larger studies, possibly on independent cohorts, to confirm our preliminary findings.
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy.
authors: Damiano
authors: D
authors: Magrì
authors: Cardiologia SUN, Monaldi Hospital, II University of Naples, Naples, Italy.
authors: Giuseppe
authors: G
authors: Limongelli
authors: Cardiology Division, Cardiac Arrhythmia Center and Cardiomyopathies Unit, San Camillo-Forlanini Hospital, Rome, Italy.
authors: Federica
authors: F
authors: Re
authors: Centro Cardiologico Monzino, IRCCS, Milan, Italy Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
authors: Piergiuseppe
authors: P
authors: Agostoni
authors: Cardiology Division, Cardiac Arrhythmia Center and Cardiomyopathies Unit, San Camillo-Forlanini Hospital, Rome, Italy.
authors: Elisabetta
authors: E
authors: Zachara
authors: Department of Cardiology, University of Foggia, Foggia, Italy.
authors: Michele
authors: M
authors: Correale
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy.
authors: Vittoria
authors: V
authors: Mastromarino
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy.
authors: Caterina
authors: C
authors: Santolamazza
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy.
authors: Matteo
authors: M
authors: Casenghi
authors: Cardiologia SUN, Monaldi Hospital, II University of Naples, Naples, Italy.
authors: Giuseppe
authors: G
authors: Pacileo
authors: Cardiologia SUN, Monaldi Hospital, II University of Naples, Naples, Italy.
authors: Fabio
authors: F
authors: Valente
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy.
authors: Beatrice
authors: B
authors: Musumeci
authors: Department of Scienze Economiche, politiche e delle lingue moderne, Libera Università SS Maria Assunta, Rome, Italy Centre for Innovation and Leadership in Health Sciences, University of Southampton, Southampton, UK.
authors: Antonello
authors: A
authors: Maruotti
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy IRCCS, Neuromed, Pozzilli (IS), Italy.
authors: Massimo
authors: M
authors: Volpe
authors: Department of Clinical and Molecular Medicine, University of Rome "La Sapienza", Rome, Italy.
authors: Camillo
authors: C
authors: Autore
mesh_terms: D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors