EFFECT OF RESIDENTIAL CARDIAC REHABILITATION FOLLOWING BYPASS-SURGERYOBSERVATIONS IN SWITZERLAND

Background: Cardiac rehabilitation in central Europe traditionally inv olves isolating patients in a residential idyllic setting where exerci se is pet-formed frequently but in a relatively unstructured fashion. Few studies have been performed on the effects of these programs among patients who have undergone bypass surgery. Recent data suggest that postbypass patients may enter these programs too soon after surgery or that exercise is not structured enough to distinguish the benefits of rehabilitation from those experienced by a control group. Methods: Fo rty-two male patients (mean age, 58+/-7 years) were divided into exerc ise and control groups approximately 1 month after undergoing bypass s urgery. Exercise training consisted of 1 h of group walking twice dail y, with the intensity stratified into four levels based on initial exe rcise capacity, Using a crossover design, patients in the exercise gro up participated in rehabilitation for 1 month, followed by 1 month of usual care, while control patients underwent the opposite sequence. At 1, 2, and 3 months, patients in both groups underwent pulmonary funct ion testing and maximal ramp exercise testing using lactate and gas ex change analysis. Results: A main effect for maximal oxgen uptake was o bserved; significant improvements within each group occurred across ea ch testing period (range, 5 to 13%; p<0.05). However, there was no sig nificant interaction between groups. Mean lactate levels throughout ex ercise were reduced within both groups (p<0.01). A reduction in oxygen uptake for test 2 at the lactate threshold in the exercise group resu lted in differences between groups in lactate, heart rate, and other g as exchange variables at this point. Conclusion: Similar changes occur in the functional status of postbypass surgery patients regardless of their participation in the short but concentrated programs common in central Europe. This suggests that a significant spontaneous effect of healing occurs in the recovery phase after surgery. These programs ma y have greater efficacy if they began later after surgery, lasted long er, or were mole structured, and studies are needed to determine their effect on psychosocial factors and return to work.