Six-minute walk test

The AMADEUS registry is a prospective multicenter European registry to evaluate the safety and efficacy of the CARILLON Mitral Contour System in patients with function mitral regurgitation. Joachim Schofer recently presented 6-month clinical outcomes of 48 patients (34). Among the 30 patients with successful device placement, cardiac perforation was noted in three patients at one month and there were two deaths (6.9%) and three myocardial infarctions reported at six months. The regurgitant volume was reduced from 35 16 mL at baseline to 24 12 at six months (P <0.001) and six-minute walk test increased from a mean of 307 meters to 403 meters (P <0.001). 

New York Heart Association (NYHA) class III or IV or six-minute walk tests less than 332 meters do poorly (6). Of note, the prognosis of patients treated in the modern era with intravenous epoprostenol is improved. Although survival data is limited, comparisons are made to outdated historical controls of the 1991 NIH study, and most randomized clinical data are limited to industry-sponsored studies of 12- to 16-week duration with extension phases. This disease has a female predominance, with a mean age of diagnosis of 36.4 years. 

One of the most important and frequently used outcomes in PAH studies is the six-minute walk test. It... 

Miyamoto S, Nagaya N, Satoh T, et al. Clinical correlates and prognostic significance of six-minute walk test in patients with primary pulmonary hypertension. Am J Respir Crit Care Med 2000 161 487-92. 

Flaherty KR, Andrei A-C, Murray S, et al. Idiopathic pulmonary fihrosis prognostic value of changes in physiology and six-minute-walk test. Am J Respir Crit Care Med 2006 174 803-809. 

Although CPET is more sensitive than static PFTs in predicting work and exercise capacity, the practical value of CPET is limited. Spirometry and oximetry are usually adequate to follow the course of the disease (6). For patients with more severe disease, noninvasive six-minute walk tests (6MWT) provide additional quantitative data. 

SSc-ILD is characterized by a restrictive defect and a decreased DLco-PFTs, and especially DLco levels, correlate well with the extent of disease on HRCT (45,95,96). Rarely, scleroderma of the chest wall may cause extrathoracic restriction. Cardiorespiratory exercise testing may detect occult lung involvement by showing increased functional dead space ventilation and widened an alveolar-arterial oxygen gradient (96,97). The six-minute walk test, a simple, inexpensive and reproducible test that gives a good indication of patient s exercise capacity, has yet to be validated in SSc-ILD as an outcome measure (98,99). 

ViUalba WO, Sampaio-Bairos PD, Pereira MC, et al. Six-minute walk test for the evaluation of pulmonary disease severity in scleroderma patients. Chest 2007 131 217-222. 

Abbreviations-. IPAP/EPAP, ratio of inspirat(xy positive airway pressure and expiratory positive airway pressure NP ABG, arterial blood gas 6-MWD, six-minute walking distance 6-MWT, six-minute walk test HRQL, health-related quaUty of Ufe RVEL, right ventricular ejection fraction LVEF, left ventricular ejection fraction NIPPV, noninvasive positive pressure ventilation O2, oxygen Til, tension time index. 

Eaton T, Yoimg P, Milne D, et al. Six-minute walk, maximal exercise tests reproducihrUty in fihrotic interstitial pnermronia. Am J Respir Crit Care Med 2005 171 115(L1157. 

Olsson LG, Swedberg K, Clark AL, Witte KK, Cleland JGF. Six minute corridor walk test as an outcome measure for the assessment of treatment in randomized, blinded intervention trials of chronic heart failure a systematic review. Eur Heart J 2005 26 778-93. 

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