Improving secondary prevention in coronary bypass patients: closing the audit loop

To complete the audit loop assessing secondary preventative care of patients who had had coronary artery bypass graft (CABG) surgery.

Two separate surveys of 1000 patients who had had CABG at the regional centre between 1988 and 1997, selected in 1998 and 2001. A single page questionnaire was sent to the patient's general practitioner.

A list was sent to each general practice in Lothian, Scotland, of their patients on the CABG database and the results of the original survey. Lothian Health organised a project to contact and recall patients with cardiac disease in each practice. Sixty five (of 128) practices participated.

Blood pressure, smoking status, serum cholesterol concentrations, and prescription of lipid lowering drugs and aspirin.

918 questionnaires (92%) in the second survey were returned describing 875 patients: 151 (17%) patients smoked and 752 patients (86%) took aspirin. Mean (SD) systolic blood pressure was lower in the second survey (142.5 (19.2) mm Hg in the first survey v 139.4 (19.1) mm Hg, p < 0.005). In our first survey 34% of patients had cholesterol concentrations less than target (5.2 mmol/l). This increased from 12% of patients operated on in 1988 to 50% of patients operated on in 1997 (Spearman rank correlation 0.77, p < 0.01). In the second survey this proportion had risen to 65% and the correlation with year of operation was abolished.

By closing the audit loop, substantial improvements were shown in the management of risk factors in patients who have had coronary artery surgery in Lothian.