100 QUESTIONS IN CARDIOLOGY

35 What patterns of coronary disease are

associated with improved short and long term

survival after CABG compared with medical

therapy?

Martin Paul Hayward

Many factors have influenced the short and long term results of

bypass surgery, not least the improvements in surgical

techniques and experience, changes in the population of patients

undergoing surgery, many of whom would never have been

deemed suitable for surgery even 10 years ago, improvements in

postoperative medical management and the use of the left

internal mammary artery (LIMA) as the graft of choice for the left

anterior descending coronary artery (LAD) in virtually all

patients today.

30 day operative mortality

Short term survival after bypass surgery is 1–3% at most

institutions around the world. The Society of Thoracic Surgeons

National Database mortality figures^1 for 80,881 patients under-

going isolated bypass surgery between 1980 and 1990 were

4.75% for left main disease, 3.32% for triple vessel disease and

2.86% for one and two vessel disease. In-hospital mortality was

2.9% for first time operation and 7.14% for re-operation.

Recognised factors affecting in-hospital mortality include older

age, female sex, co-morbid renal and cardiovascular disease,

diabetes, cardiogenic shock, emergency, salvage or redo

operation, preoperative intra-aortic balloon pump use and

associated valve disease.

Long term survival after surgery

The late results of bypass surgery depend on the extent of cardiac

disease, the effectiveness of the original operation, progression

rate of atherosclerosis and the impact of non-cardiac disease.

Patient-related variables associated with poorer late survival

include reduced ventricular function, congestive cardiac failure,

triple vessel or left main stem disease, severity of symptoms,

advanced age and diabetes.