A simplified method of stabilization and hemostasis for minimally invasive coronary artery bypass

Off-pump multivessel revascularization: efficacy of suction type of coronary stabilizer

OBJECTIVE

Off-pump coronary artery bypass grafting (CABG) has come into widespread use with the availability adequate coronary stabilization devices. We studied the efficacy of second-generation coronary stabilization devices (suction device) comparing to the first-generation device (compression device).

METHODS

We prospectively analyzed consecutive patients who underwent isolated off-pump CABG via a midline sternotomy at Shin-Tokyo Hospital Group between July 1, 1996, and August 31, 2000, comparing perioperative, and follow-up data in the group using a suction device (group S) to that in the group using a compression device (group C).

RESULTS

Preoperative risk factors were identical between the two groups, with the exception of a higher incidence of three vessel disease in group S. Complete revascularization increased from 47.3% in group C to 88.1% in group S, and the number of distal anastomoses from 2.1 +/- 0.6 in group C to 2.9 +/- 0.9 in group S. Revascularization of the circumflex artery was achieved in 21.7% of group S patients, which was significantly higher than that in group C (2.2%). Postoperative recovery, mortality, and morbidity did not differ significantly between groups. Calculated event-free rates at 2 years was 88.7% in group C and 92.0% in group S (p = NS).

CONCLUSIONS

Anastomosis to the posterior wall of the heart using the suction device is safe. An increased number of distal anastomoses may reduce the occurrence of cardiac events related to incomplete revascularization.

Off-pump coronary artery bypass grafting for patients with three-vessel disease

BACKGROUND

Off-pump coronary artery bypass grafting (CABG) has been performed since 1996 in our institute, and its application has recently been expanded to patients with three-vessel disease. A study was performed to clarify the benefit of off-pump CABG for patients with three-vessel disease.

METHODS

Between June 1, 1991 and September 30, 2001, a total of 1089 patients with three-vessel disease (832 men and 257 women; mean age, 64.0 +/- 9.1 years) underwent on-pump CABG. After 1997, a total of 310 patients with three-vessel disease (223 men and 87 women; mean age, 68.8 +/- 8.6 years) underwent off-pump CABG. Data of the historical cohort of on-pump CABG and the concurrent cohort of off-pump CABG were analyzed retrospectively.

RESULTS

The 2 groups were age and gender matched. Significant comorbidities were more often observed in the off-pump group than in the on-pump group. The mean number of bypass grafts in the off-pump versus on-pump CABG was 3.3 vs 3.7, P <.0001. The mean intubation period, intensive care unit stay, and postoperative hospital stay were 7.9 vs 11.7 hours, 2.2 vs 3.0 days, and 14.5 vs 17.5 days, respectively (P <.0001). In-hospital mortality rate (0.6% vs 1.2%, respectively) and morbidity rates (10.3% vs 12.9%, respectively) were not significantly different. After surgery, calculated event-free rates at 2 years were 93.3% vs 91.9%, respectively; P = not significant.

CONCLUSIONS

In patients with multivessel disease, off-pump CABG provided early recovery, and its complication rates and early follow-up results were equivalent to on-pump CABG.

On-pump versus off-pump coronary artery bypass using quadruple arterial grafts

The optimal combination of arterial grafts for quadruple coronary artery bypass is the bilateral internal mammary artery, the radial artery, and the gastroepiploic artery. Patients who underwent quadruple bypass in our hospital group between December 1995 and March 2001 were retrospectively analyzed to determine whether off-pump surgery (n = 27) provides better outcomes than conventional on-pump surgery (n = 51). Preoperative risk factors as well as the mean number of distal anastomoses (4.5 in the off-pump versus 4.8 in the on-pump patients) were not significantly different between the 2 groups. Postoperative recovery was significantly faster in the off-pump group than in the on-pump group (intubation time, 6.4 versus 16 hours; stay in intensive care unit, 2 versus 3 days; and postoperative hospital stay, 12.3 versus 15.8 days). Early stenosis-free graft patency rates did not differ significantly (90.3% versus 89.3%). No late cardiac events were observed in the off-pump group, while 4 occurred in the on-pump group. Quadruple arterial bypass without cardiopulmonary bypass is safe, and it allows faster recovery. The follow-up results of off-pump patients so far have been satisfactory.

Alternatives to unfractionated heparin for anticoagulation in cardiopulmonary bypass

Despite the progress made in the development of cardiopulmonary bypass (CPB) equipment, systemic anticoagulation with unfractionated heparin and post-bypass neutralization with protamine are still used in most perfusion procedures. However, there are a number of situations where unfractionated heparin, protamine or both cannot be used for various reasons. Intolerance of protamine can be addressed with extracorporeal heparin removal devices, perfusion with (no) low systemic heparinization and, to some degree, by perfusion with alternative anticoagulants. Various alternative anticoagulation regimens have been used in cases of intolerance to unfractionated heparin, including extreme hemodilution, low molecular weight heparins, danaparoid, ancrod, r-hirudin, abciximab, tirofiban, argatroban and others. In the presence of heparin-induced thrombocytopenia (HIT) and thrombosis, the use of r-hirudin appears to be an acceptable solution which has been well studied. The main issue with r-hirudin is the difficulty in monitoring its activity during CPB, despite the fact that ecarin coagulation time assessment is now available. A more recent approach is based on selective blockage of platelet aggregation by means of monoclonal antibodies directed to GPIIb/IIIa receptors (abciximab) or the use of a GPIIb/IIIa inhibitor (tirofiban). An 80% blockage of the GPIIb/IIIa receptors and suppression of platelet aggregation to less than 20% allows the giving of unfractionated heparin and running CPB in a standard fashion despite HIT and thrombosis. Likewise, at the end of the procedure, unfractionated heparin is neutralized with protamine as usual and donor platelets are transfused if necessary. GPIIb/IIIa inhibitors are frequently used in interventional cardiology and, therefore, are available in most hospitals.

Off-pump coronary artery bypass. Mid-term results

OBJECTIVES

Off-pump coronary artery bypass grafting (CABG) on the beating heart has become popular procedure in cardiac surgery and its initial results appeared favorable. We report our early and mid-term results of off-pump CABG performed at Shin-Tokyo Hospital.

METHODS

Medical records of patients undergoing off-pump or conventional on-pump CABG from September 1, 1996, to August 31, 1999 were retrospectively reviewed. Patients underwent off-pump CABG were further classified into 2 groups; MIDCAB (Off-pump CABG for single vessel revascularization via a small skin incision) and OPCAB (off-pump CABG mainly approached via midline sternotomy) group. Their preoperative, perioperative, and follow-up data were collected and analyzed.

RESULTS

Among a total of 995 cases of CABG, 194 cases were off-pump CABG (male/female 142/52, mean age 66.9). The mean number of distal anastomoses in off-pump CABG was 1.9 +/- 0.9 (1.0 +/- 0.0 in MIDCAB and 2.3 +/- 0.7 in OPCAB), which was significantly fewer than in on-pump CABG (3.6 +/- 1.1), with p < 0.0001. Intubation time (5.3 +/- 5.7 hours in off-pump CABG vs 13.1 +/- 24.2 hours in on-pump CABG), ICU stay (1.7 +/- 1.1 vs 3.2 +/- 3.0 days), and postoperative hospital stay (14.0 +/- 7.9 vs 18.1 +/- 12.1 days) in off-pump CABG were significantly shorter than in on-pump CABG (p < 0.0001). In the off-pump CABG group, there were no in-hospital deaths and 14 major complications, fewer than in on-pump CABG (8 hospital deaths and 114 major complications). Postoperative angiography before hospital discharge was conducted in 80 patients (41.2%) and showed 2 occlusions, giving a graft patency rate of 98.6% in the off-pump group. During follow-up (0.9 +/- 0.6 year) period, there were 5 non-cardiac deaths and 20 cardiac events in the off-pump group. The actuarial survival rate at 36 months was 94.6% for off-pump CABG, showing no significant difference from the rate for conventional CABG patients (95.2% at 36 month, p = NS) The event-free rate was 84.0% at 36 months in off-pump CABG patients; however, which was less favorable than on-pump CABG patients (88.0% at 36 months, p < 0.05).

CONCLUSIONS

Both in-hospital and mid-term results for off-pump CABG patients were acceptable. Isolated CABG can thus be safely performed without cardiopulmonary bypass. Advances in coronary stabilization have contributed to these improved results. The observed long-term cardiac events may be related to incomplete revascularization.