Analysis of mortality within the first six months after coronary reoperation

BACKGROUND: Identify risk factors associated with mortality following repeat coronary revascularization (redoCABG) within the first 6 months following surgery. METHODS: Five hundred forty-one redoCABG patients (1987 to 1998) were studied by univariant and multivariant analysis. Mortality was assessed at three different points: hospital mortality (A) (36/541, 6.7%); mortality at 6 months (C) (75/541, 13.9%); and outpatient perioperative mortality, which is a death occurring from the time of hospital discharge to 6 months postoperatively (B) (39/541, 7.2%). RESULTS: Diabetes, hypertension, peripheral vascular disease, renal insufficiency, lung disease, myocardial infarction (MI) before the first operation, MI between the first and redoCABG, lack of sinus rhythm, no IMA graft, acute/emergency operation, perfusion time, and perioperative MI were all identified as risk factors related to early mortality. MI before the first operation, antegrade cardioplegia, and the time period 1987 to 1992 all influenced hospital mortality (A). Diabetes, hypertension, renal insufficiency, lung disease, and valvular heart disease all influenced the outpatient mortality up to 6 months. Independent predictive factors for early mortality were: age more than 69 years; diabetes; vascular insufficiency; chronic lung disease; MI between first and redoCABG; no IMA-graft; acute preoperative MI; emergency operation; perfusion time; perioperative MI; and the time period 1987 to 1992. Risk factors for in-hospital death included MI between the first and redoCABG, cardiopulmonary bypass time, and the time period 1987 to 1992. Diabetes is an important risk factor during the outpatient perioperative phase. Emergency surgery and perioperative MI predict mortality regardless of the time period (A, B, or C). CONCLUSIONS: Early mortality after redoCABG is influenced by many variables during the first 6 months following surgery. Understanding these factors and their time course may better help to assess the true risk associated with reoperation for recurrent coronary insufficiency.