Systolic blood pressure and (cardiac) mortality over 15 years after venous coronary bypass surgery.

Objective: The aim of the present study was to determine the influence of pre-operative systolic blood pressure and systolic blood pressure 1 and 5 years after venous coronary bypass surgery on subsequent cardiac and non-cardiac mortality.

Design: A prospective 15 years follow-up study.

Patients: A series of 446 consecutive coronary bypass surgery patients, operated on between April 1976 and April 1977. According to their systolic blood pressure, patients were divided into five groups.

Main Outcome Measures: Systolic blood pressure 5 years after surgery, but not pre-operative systolic blood pressure, was an independent predictor of cardiac mortality.

Results: Multivariate Cox proportional hazards analysis revealed that pre-operative systolic blood pressure was not associated with cardiac mortality, while higher systolic blood pressure 1 year after surgery showed a trend towards increased cardiac mortality. Systolic blood pressure 5 years after surgery appeared to be a strong independent predictor of cardiac mortality during the subsequent follow-up period. Patients with a systolic blood pressure of 130-139 mmHg had the lowest risk. Compared to this group, the cardiac mortality risk in patients with a systolic blood pressure 5 years after surgery of 140-149 mmHg, 150-159 mmHg and > or = 160 mmHg, was 2.3 (1.2 to 4.6), 3.4 (1.6 to 7.1) and 3.1 (1.4 to 6.5) times higher. Systolic blood pressure < 130 mmHg 5 years after surgery was also associated with a 2.3 times (1.1 to 4.7) times increased risk for cardiac mortality, compared to patients with a systolic blood pressure of 130-139 mmHg.

Conclusions: These findings underline the importance of systolic blood pressure control in the initial years after coronary bypass surgery.