A NON RANDOMISED TRIAL OF 'ON BYPASS' Vs 'OFF BYPASS' CORONARY ARTERY REVASCULARISATION

Abstract

BACKGROUND: Several groups have reported a decreased postoperative morbidity and length of hospital
stay in 'off pump' coronary artery bypass grafting (CABG). We report on our initial 'off by-pass' CABG
series and these compare with the unselected consecutive patients operated upon the same time period in our
institution
METHODS: We retrospectively collected data of 100 consecutive patients who underwent CABG with
cardiopulmonary bypass (Group A=55 patients) or without cardiopulmonary by-pass (Group B=45 patients)
during a 4-months period. In the patients in Group A normothermic cardiopulmonary bypass was used with
intermittent aortic cross-clamping and ventricular fibrillation. In Group B a CTS Access System
(Cardiothoracic Systems, Cupertino, Ca, USA) was used to allow adequate exposure and stabilisation of the
coronary arteries. Mean age of the patients in group A was 55 years while 63 years in Group B. Four patients
in Group B had experienced a cerebral vascular accident in the 12 months preceding the heart operation and
3 patients had asymptomatic severe bilateral carotid artery disease. The average number of grafts was 3±1 in
Group A vs. 2.5±0.8 in Group B in which branches of the Circumflex artery were revascularised in 21
patients (42%). In 50 % of the patients in Group A and in 5% in Group B at least two arterial grafts were
used.
RESULTS: There was no hospital death. Post operative myocardial infarctions or ischemic ECG changes
were not recorded in either of the two groups. Mean intubation time and ICU stay were similar in Group A
and in Group B. Mean hospital stay was 5 days in Group A while it was 5.7 days in the 'off by-pass' group.
The incidence of post-operative atrial fibrillation was 5.4% in Group A while 15% in Group B.
CONCLUSION: Our initial experience failed to show an advantage in the early post-operative period in the
patients operated 'off by-pass' compared to the ones 'on by-pass'. The 'non randomised' allocation of patients
with more non cardiac co-morbid conditions towards the 'off by-pass' treatment group may explain these
early findings. Further studies and randomised trials are needed before OPCAB used as routine procedure.