Outcome analysis of coronary artery bypass grafting: minimally invasive versus standard techniques

Abstract

Minimally invasive coronary artery bypass grafting (MIDCAB) procedures are purported to result in improvements in patient management over standard techniques. A comparative study was performed on risk-stratified patients treated with either technique. Following institutional review board approval, a retrospective random chart review was conducted on 27 MIDCAB and 37 standard coronary artery bypass grafting (CABG) patients who were operated on over a 12-month period at the University of Nebraska Medical Center. Risk stratification was accomplished by dividing the two patient populations, MIDCAB and ‘standard’, into one of four subgroups based on a preoperative risk score. Risk stratification was achieved by dividing the patient populations into one of four subgroups: good, fair, poor and high risk. Both groups received similar operations and surgical interventions, except for the inclusion of cardiopulmonary bypass (CPB). Approximately 200 parameters were collected and analyzed in the following categories: anthropometric, operative and postoperative outcomes.

The MIDCAB group had a significantly lower number of vessels bypassed (2.0 ± 0.7 vs 3.4 ± 0.9, p < 0.0001). Total postoperative blood product transfusions trended higher in the standard group (6.1 ± 12.6 U) when compared to the MIDCAB patients (2.3 ± 5.5 U, p < 0.15), although not statistically significant. Postoperative inotrope use was significantly less in the MIDCAB group (19% vs 59%, p < 0.002). Ventilator time in the MIDCAB group was 10.5 ± 5.4 h vs 15.0 ± 12.3 h in the standard group (p < 0.07). The MIDCAB group had an overall greater length of stay, but was only statistically different within the poor-risk subgroup (12.2 ± 10.7 vs 7.5 ± 3.9, p < 0.04).

The results of this study show that when CPB is not utilized in treating patients undergoing CABG procedures, the benefits in regards to patient outcomes are unclear. This necessitates the need for further work when comparing outcomes for risk-stratified patients.

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References

Favaloro RG. Saphenous vein graft in surgical treatment of coronary artery disease . J Thorac Cardiovasc Surg 1969; 58: 178-185 .

Mishkovitz Y , Lusky A , Mohr R. Coronary artery bypass without cardiopulmonary bypass: analysis of short-term and mid-term outcome in 220 patients . J Thorac Cardiovasc Surg 1995; 110: 979-987 .

Acuff TE , Landreneau RJ , Griffith BP , Mack MJ. Minimally invasive coronary artery bypass grafting . Ann Thorac Surg 1996; 61: 135-137 .

Lazar HL , Fitzgerald C , Gross S , Heeren T , Aldea GS , Shemin RJ. Determinants of length of stay after coronary artery bypass graft surgery . Circulation 1992; Suppl. II: II-2-II-24 .

Wahl GW , Swinburne AJ , Fedullo AJ , Lee DK , Bixby K. Long-term outcome when major complications follow coronary artery bypass graft surgery . Chest 1996; 110: 1394-1398 .

Westaby S , Benetti FJ. Less invasive coronary surgery: consensus from the Oxford meeting . Ann Thorac Surg 1996; 62: 924-931 .

Benetti FJ , Naselli G , Wood M , Geffner L. Direct myocardial revascularization without extracorporeal circulation . Chest 1991; 100: 312-316 .

Lachat M , Vogt PR , Niederhauser U et al. Minimally invasive coronary artery bypass techniques as adjunct to extracardiac procedures . Ann Thorac Surg 1997; 63: S61-S63 .

Arom KV , Emery RW , Nicoloff DM , Flavin TF , Emery AM. Minimally invasive direct coronary artery bypass grafting: experimental and clinical experiences . Ann Thorac Surg 1997; 63; S48-S52 .

10.

Dickenson TA. How to do it: utilizing risk stratification to evaluate outcomes in adult open-heart operations . J Extracorp Technol 1993; 24: 135-140 .

11.

Pfister AJ , Zaki S , Garcia JM et al. Coronary artery bypass without cardiopulmonary bypass . Ann Thorac Surg 1992; 54: 1085-1092 .

12.

Buffolo E , Silva de Andrade JC , Branco JN , Teles CA , Aguiar LF , Gomes WJ. Coronary artery bypass grafting without cardiopulmonary bypass . Ann Thorac Surg 1996; 61: 63-66 .

13.

Lytle BW. Minimally invasive cardiac surgery . J Thorac Cardiovasc Surg 1996; 111: 554-555 .

14.

Buffolo E , Silva de Andrade JC , Branco JNR , Aguiar LF , Ribeiro EE , Jatene AD. Myocardial resvacularization without extracorporeal circulation . Eur J Cardiothorac Surg 1990; 4: 504-508 .

15.

Follette D , Steed D , Foglia R , Fey K , Buckberg G. Advantages of intermittent blood cardioplegia over intermittent ischemia during prolonged hypothermic aortic clamping . Circulation 1977; 56 (Suppl. III): III-248-III-248 .

16.

Akins CW , Boucher CA , Pohost GM. Preservation of interventicular septal function in patients having coronary artery bypass grafts without cardiopulmonary bypass . Am Heart J 1984; 107: 304-309 .

17.

Benetti EJ. Direct coronary surgery with saphenous vein bypass without either cardiopulmonary bypass or cardiac arrest . Cardiovasc Surg 1985; 26: 217-222 .

18.

Moshkovitz Y , Mohr R. Coronary artery bypass without cardiopulmonary bypass-the pros and cons . Isr J Med Sci 1993; 29: 716-720 .

19.

Bar-El Y , Goor DA. Clamping of the atherosclerotic ascending aorta during coronary artery bypass operations . J Thorac Cardiovasc Surg 1992; 104: 469-474 .

20.

Chenoweth DE , Cooper SW , Hugli TE , Stewart RW , Blackstone EH , Kirklin JW. Complement activation during cardiopulmonary bypass . N Engl J Med 1981; 304: 497-503 .