Circulatory response to a 50-m walk in the coronary care unit in acute coronary syndrome.

BACKGROUND

Lack of a standardized and monitored technique to start rehabilitation of patients with acute coronary syndrome (ACS) in the coronary care unit.

OBJECTIVE

To describe the technique of and circulatory response to a 50-m walk (W50m).

METHODS

Experimental cross-sectional study of 65 patients with ACS; of these, 36 (54%) with acute myocardial infarction (AMI), Killip I, 29 (45.2%) with unstable angina (UA), 61.5% males with age of 62.8 +/- 12.7 years. Walk was started 45+/-23 h after hospitalization. Parameters measured: systolic blood pressure (SBP mmHg), diastolic blood pressure (DBP mmHg), heart rate (HR bpm), double product (SBP mmHg X HR bpm), peripheral oxygen saturation (SpO2%), walking time, and exercise tolerance by Borg scale (BS). Measurements were taken while supine, sitting, in orthostasis (phase 1 [gravitational stress]), end of the walk, and after a 5-minute rest (phase 2 [exercise stress]).

RESULTS

Increased HR in response to the sitting gravitational stress (Delta=4.18) and with orthostasis (Delta=2.69) (p<0.001) was observed. At the end of walk, there was an elevation in SBP (Delta=4.84), (p<0.001), HR (Delta=4.68), (p<0.001) and DP (Delta=344.97), (p=0.004), and a reduction in SpO2 (Delta=-1.42), (p<0.001), with return to baseline values after 5 minutes. Walking time was 2'36''+/-1'17'', and exercise tolerance by BS was good. SBP response >or= 142 mmHg when sitting was associated with a significant increase (p=0.031) of 11 mmHg at exercise in 13 patients with overweight/obesity and 85% with hypertension. Adverse effects occurred in 19 (29.2%) patients and dizziness in 23.1%, which impaired the walk in three of them.

CONCLUSION

In this sample, patients did not present severe collateral effects to W50m. 24 hours after a coronary event.