Prognostic value of indeterminable anaerobic threshold in heart failure
Piergiuseppe Agostoni, Ugo Corrà, Gaia Cattadori, Fabrizio Veglia, Elisa Battaia, Rocco La Gioia, Angela B Scardovi, Michele Emdin, Marco Metra, Gianfranco Sinagra, Giuseppe Limongelli, Rosa Raimondo, Federica Re, Marco Guazzi, Romualdo Belardinelli, Gianfranco Parati, Damiano Magrì, Cesare Fiorentini, Mariantonietta Cicoira, Elisabetta Salvioni, Marta Giovannardi, Alessandro Mezzani, Domenico Scrutinio, Andrea Di Lenarda, Valentina Mantegazza, Roberto Ricci, Anna Apostolo, Annamaria Iorio, Stefania Paolillo, Pietro Palermo, Mauro Contini, Corrado Vassanelli, Claudio Passino, Massimo F Piepoli, MECKI Score Research Group, Erica Bertella, Stefania Farina, Gabriella Malfatto, Giuseppe Pacileo, Teo Roselli, Andrea Buono, Raffaele Calabrò, Andrea Passantino, Daniela Santoro, Saba Campanale, Domenica Caputo, Donatella Bertipaglia, Emanuela Berton, Luigi E Pastormerlo, Raffaella Vaninetti, Marco Confalonieri, Pantaleo Giannuzzi, Livio Dei Cas, Pasquale Perrone Filardi, Paola Gargiulo, Piergiuseppe Agostoni, Ugo Corrà, Gaia Cattadori, Fabrizio Veglia, Elisa Battaia, Rocco La Gioia, Angela B Scardovi, Michele Emdin, Marco Metra, Gianfranco Sinagra, Giuseppe Limongelli, Rosa Raimondo, Federica Re, Marco Guazzi, Romualdo Belardinelli, Gianfranco Parati, Damiano Magrì, Cesare Fiorentini, Mariantonietta Cicoira, Elisabetta Salvioni, Marta Giovannardi, Alessandro Mezzani, Domenico Scrutinio, Andrea Di Lenarda, Valentina Mantegazza, Roberto Ricci, Anna Apostolo, Annamaria Iorio, Stefania Paolillo, Pietro Palermo, Mauro Contini, Corrado Vassanelli, Claudio Passino, Massimo F Piepoli, MECKI Score Research Group, Erica Bertella, Stefania Farina, Gabriella Malfatto, Giuseppe Pacileo, Teo Roselli, Andrea Buono, Raffaele Calabrò, Andrea Passantino, Daniela Santoro, Saba Campanale, Domenica Caputo, Donatella Bertipaglia, Emanuela Berton, Luigi E Pastormerlo, Raffaella Vaninetti, Marco Confalonieri, Pantaleo Giannuzzi, Livio Dei Cas, Pasquale Perrone Filardi, Paola Gargiulo
Abstract
Background: In patients with heart failure (HF), during maximal cardiopulmonary exercise test, anaerobic threshold (AT) is not always identified. We evaluated whether this finding has a prognostic meaning.
Methods and results: We recruited and prospectively followed up, in 14 dedicated HF units, 3058 patients with systolic (left ventricular ejection fraction <40%) HF in stable clinical conditions, New York Heart Association class I to III, who underwent clinical, laboratory, echocardiographic, and cardiopulmonary exercise test investigations at study enrollment. We excluded 921 patients who did not perform a maximal exercise, based on lack of achievement of anaerobic metabolism (peak respiratory quotient ≤1.05). Primary study end point was a composite of cardiovascular death and urgent cardiac transplant, and secondary end point was all-cause death. Median follow-up was 3.01 (1.39-4.98) years. AT was identified in 1935 out of 2137 patients (90.54%). At multivariable logistic analysis, failure in detecting AT resulted significantly in reduced peak oxygen uptake and higher metabolic exercise and cardiac and kidney index score value, a powerful prognostic composite HF index (P<0.001). At multivariable analysis, the following variables were significantly associated with primary study end point: peak oxygen uptake (% pred; P<0.001; hazard ratio [HR]=0.977; confidence interval [CI]=0.97-0.98), ventilatory efficiency slope (P=0.01; HR=1.02; CI=1.01-1.03), hemoglobin (P<0.05; HR=0.931; CI=0.87-1.00), left ventricular ejection fraction (P<0.001; HR=0.948; CI=0.94-0.96), renal function (modification of diet in renal disease; P<0.001; HR=0.990; CI=0.98-0.99), sodium (P<0.05; HR=0.967; CI=0.94-0.99), and AT nonidentification (P<0.05; HR=1.41; CI=1.06-1.89). Nonidentification of AT remained associated to prognosis also when compared with metabolic exercise and cardiac and kidney index score (P<0.01; HR=1.459; CI=1.09-1.10). Similar results were obtained for the secondary study end point.
Conclusions: The inability to identify AT most often occurs in patients with severe HF, and it has an independent prognostic role in HF.
Keywords: exercise; follow-up studies; heart failure; oxygen; prognosis.
Source: PubMed