Rationale:

ST segment depression is seen in the post coronary artery bypass graft (CABG) patient during Phase II cardiac rehabilitation (CR), but its significance is unclear and there is a paucity of information about it in the literature. We hypothesized that ischemic ECG signs are not uncommon in this patient population, but unlike other populations in CR, a revision in medical management (RMM) as a result of the finding is not likely.

Objective:

To assess the presence of ischemic electrocardiographic (ECG) signs in post CABG patients and to determine if RMM as a result of the finding is as common as it is with other patients.

Methods:

From January 2000, RMM have been tracked on all patients in CR; to date 618 patients (71% male) are available for analysis. ECG ischemia is defined as ST segment depression of >=1 mm 80 msec after the J-point with normal QRS complex. Eighty-six subjects were eliminated because of QRS abnormalities resulting in 532 subjects for analysis.

Results:

Of the eligible subjects, 137 (25.75%) underwent CABG. Of those 17 (12.4%) showed ECG ischemia at least once during CR compared with 76 (19.2%) of all others. Additional testing or hospitalization with re-catheterization occurred for 2.5% and 4.1% respectively for the non-CABG patients and 0% and 2.2% respectively for the CABG patients.

Conclusions:

During Phase II CR, ECG signs suggestive of ischemia occur in 12.4% of patients with CABG and 19.2% of all other patients. Additional testing or hospitalization with re-catheterization is rare for the patient who underwent CABG.