Six-minute walk test enhanced by mobile telemetric cardiopulmonary monitoring

The 6-min walk test (6MWT) is frequently used to assess overall cardiopulmonary fitness and to predict outcome, but it yields little diagnostic information. Portable telemetric devices allow performing the 6MWT with real-time cardiopulmonary monitoring.

The study was designed to analyze feasibility, safety and clinical usefulness of a mobile cardiopulmonary monitoring (MOB)-enhanced 6MWT.

From August 2003 to June 2007, 261 consecutive patients with chronic lung and/or heart disease as well as healthy controls underwent MOB-enhanced 6MWTs. A subgroup of 33 individuals had the test done with and without cardiopulmonary monitoring on independent days.

No test-related adverse events occurred throughout the study. Whether the 6MWT was done without or with cardiopulmonary monitoring (n = 33) did not significantly influence the walking distance (WD: 528 ± 183 vs. 525 ± 192 m; nonsignificant). Fifty-nine percent (155/261) of the patients fulfilled the maximal test criteria. Distinct disease-specific exercise response patterns as well as treatable co-pathologies were observed. The validity of response patterns was better in case of a maximal test.

An MOB-enhanced 6MWT is feasible within daily routine and safe in patients with various diseases. It does not negatively affect WD. MOB is a valuable tool to identify factors limiting exercise in patients irrespective of their underlying disease.