HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Hani Shennib Jean F. Morin Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Shennib, H. Articles by Morin, J. F. Search for Related Content PubMed PubMed Citation Articles by Shennib, H. Articles by Morin, J. F. Related Collections Minimally invasive surgery

Ann Thorac Surg 2002;74:S1344-S1347
© 2002 The Society of Thoracic Surgeons

---

Supplement: Cardiothoracic Techniques and Technologies

Surgical revascularization in patients with poor left ventricular function: on- or off-pump?

^a Division of Cardiothoracic Surgery, The Montreal General Hospital, Montreal, Quebec, Canada

* Address reprint requests to Dr Shennib, Division of Cardiothoracic Surgery, The Montreal General Hospital, 1650 Cedar Avenue, Room L9-121, Montreal, QC, H3G 1A4, Canada
e-mail: hani.shennib{at}muhc.mcgill.edu

Presented at the Eighth Annual Cardiothoracic Techniques and Technologies Meeting 2002, Miami Beach, FL, Jan 23–26, 2002.

	Abstract

Top Abstract Introduction Patients and methods Results Comment References

 
BACKGROUND: Patients with left ventricular dysfunction and low ejection fraction (EF) are at high-risk of complication and mortality after coronary artery bypass grafting (CABG). The potential success of off-pump CABG in this high-risk population has yet to be determined. The purpose of this study is to compare the outcome of off-pump coronary artery bypass (OPCAB) and conventional coronary artery bypass (CCAB) in patients with poor left ventricular function, all from a single institution.

METHODS: Data on patient demographics, preoperative risk factors, operative and postoperative outcomes were collected retrospectively on all patients having undergone isolated CABG between January 1, 1998, and October 31, 2001.

RESULTS: A total of 77 patients (31 OPCAB/46 CCAB) were identified as having an ejection fraction (EF) of 0.35. Of these, 52 had EF 0.30 (21 OPCAB/31 CCAB) and 31 patients had EF 0.25 (10 OPCAB/21 CCAB). Operative mortality was 3.2% after the OPCAB procedure versus 10.9% for the CCAB (p = 0.39). Use of intraaortic balloon pump (6.5%) was rarely required. The OPCAB procedure resulted in significantly less requirement for blood transfusions (p < 0.05), fewer distal anastomoses per patient (p < 0.01), and a higher incidence of atrial fibrillation (p < 0.05) compared with CCAB.

CONCLUSIONS: Patients with poor left ventricular function may undergo surgical revascularization using off-pump technique with relatively good results and low mortality levels. The lower number of grafts performed on the off-pump procedure did not seem to affect clinical outcomes.

	Introduction

Top Abstract Introduction Patients and methods Results Comment References

 

Dr Shennib discloses that he has a financial relationship with CTTTM.

 

Numerous investigations have shown the off-pump coronary artery bypass (OPCAB) procedure to hold some advantages over conventional coronary artery bypass (CCAB) using cardiopulmonary bypass (CPB) [1–5]. Patients with left ventricular dysfunction and low ejection fraction (EF) are known to be particularly at risk of complication after surgical coronary revascularization. The purpose of this study was to compare the effects of off-pump and on-pump coronary artery bypass grafting (CABG) in patients with poor left ventricular function in a single institution.

	Patients and methods

Top Abstract Introduction Patients and methods Results Comment References

 
Data collection
From January 1, 1998, to October 31, 2001, a cohort of patients with poor left ventricular EF (preoperative EF 0.35) undergoing isolated multivessel CABG were enrolled in this retrospective analysis. Ejection fraction was defined preoperatively from transthoracic and transesophageal echocardiography. Unstable angina was determined when patients required continuous intravenous infusion of heparin or nitrates. Perioperative insertion of an intraaortic balloon pump (IABP) was defined as a procedure for improving hemodynamics in the presence of cardiogenic shock. Postoperative cerebrovascular accident was defined as a new neurologic event after operation, and persisting for 24 hours after onset. Atrial fibrillation was defined as sustained atrial arrhythmia requiring treatment.

Surgical technique
Surgeons determined which procedure to use (OPCAB versus CABG) according to their personal preference. After the administration of routine anesthesia, the saphenous vein harvest and median sternotomy were performed simultaneously. The left internal mammary artery was mobilized in the habitual manner. The right internal mammary artery, gastroepiploic artery, or radial artery was harvested when necessary. For the OPCAB procedure, a deep pericardial traction stitch was placed near the left lower pulmonary veins. The target vessels were stabilized with an Octopus tissue stabilizer, and heparin 1.5 mg/kg was administered. The artery was occluded with silastic tape, and an end-to-side anastomosis was completed using 7.0 Prolene sutures (Ethicon, Somerville, NJ). Proximal anastomosis was performed on the ascending aorta by conventional methods. Patients undergoing CCAB underwent single right atria and aortic cannulation, followed by cardioplegic arrest. After the completion of anastomosis, thoracic and pericardial chest drains were inserted, and the chest subsequently closed.

Statistical analysis
All statistical analyses were performed using the SAS statistical analysis software (SAS Inc, Cary, NC). Values are shown as mean ± standard deviation. The data were found to be normally distributed. Categorical variables were analyzed using the -square or Fisher’s exact test. Constant variables were examined using the unpaired t test, or the Mann-Whitney U test.

	Results

Top Abstract Introduction Patients and methods Results Comment References

 
A total of 77 patients (31 OPCAB/46 CCAB) with EF 0.35 were analyzed. Preoperative patients characteristics are summarized in Table 1. The mean age of patients was 64.5 ± 9.5 years (median 67.0 years). The sample consisted of 66 men (85.7%) and 11 women (14.3%). The mean left ventricular EF and the mean Parsonnet score were 28.6 ± 5.9 and 9.5 ± 6.5, respectively. Fifty-two patients had EF 0.30 (21 OPCAB/31 CCAB) and 31 patients had EF 0.25 (10 OPCAB/21 CCAB). More patients in the CCAB group than in the OPCAB group experienced acute myocardial infarction (AMI) within 7 days (p < 0.05) prior to surgery.

	Comment

Top Abstract Introduction Patients and methods Results Comment References

The operative data suggested fewer grafts to the obtuse marginal branch (p < 0.01) and posterior descending artery (p < 0.01) in the OPCAB group. However, 10 of the patients in the OPCAB group did not have significant stenosis in the left circumflex artery. A large reduction in the requirement of allogenic blood transfusion was observed in the OPCAB group (p < 0.05). Patients in the OPCAB group needed less postoperative ventilatory support (p = 0.05) and had shorter stays in the intensive care unit (p = 0.08) when compared with patients in the CCAB group. However, postoperative stay in the hospital was similar for both groups. Although avoidance of CPB during the CABG operation apparently reduces the inflammatory response, postoperative data clinical from the OPCAB group did not reflect this assumption.

A unique observation was an increased incidence of atrial fibrillation in the OPCAB group with LV dysfunction, in contradiction to results reported by other researchers from OPCAB patients with normal LV function. A higher mortality in the CCAB group may have contributed to the lower reported incidence of postoperative atrial fibrillation [1]. The use of IABP was rarely required (6.5%) in both groups. The incidence of postoperative morbidity such as cerebrovascular accident, cardiogenic shock, and pneumonia were low and were not significantly different in the two groups. A total of 6 patients died. Only 1 patient who underwent OPCAB died, as the result of low cardiac output failure after the operation. Five patients died in the CCAB group: 3 from low cardiac output failure a few hours after operation, and 2 suddenly on the 4th and 7th days after their respective operations. The severity of left ventricular dysfunction below 35% EF had no impact on outcomes measured (Table 4).

Many centers have observed an increase in the number of higher-risk patients referred for CABG. From this observational study, we conclude that patients with poor left ventricular function may undergo surgical revascularization using the off-pump technique with good results and low mortality.

	References

Top Abstract Introduction Patients and methods Results Comment References

 

1. Demers P., Cartier R. Multivessel off-pump coronary artery bypass surgery in the elderly. Eur J Cardiothorac Surg 2001;20:908-912.[Abstract/Free Full Text]
2. Cleveland J.C., Jr, Shroyer A.L.W., Chen A.Y., Peterson E., Grover F.L. Off-pump coronary artery bypass grafting decreases risk-adjusted mortality and morbidity. Ann Thorac Surg 2001;72:1282-1289.[Abstract/Free Full Text]
3. Lund O., Christensen J., Holme S. On-pump versus off-pump coronary artery bypass: independent risk factors and off-pump graft patency. Eur J Cardiothorac Surg 2001;20:901-907.[Abstract/Free Full Text]
4. Yokoyama T., Baumgartner F.J., Gheissari A., Capouya E.R., Panagiotides G.P., Declusin R.J. Off-pump versus on-pump coronary bypass in high-risk subgroups. Ann Thorac Surg 2000;70:1546-1550.[Abstract/Free Full Text]
5. Boyd W.D., Desai N.D., Del Rizzo D.F., Novick R.J., McKenzie F.N., Menkis A.H. Off-pump surgery decreases postoperative complications and resource utilization in the elderly. Ann Thorac Surg 1999;68:1490-1493.[Abstract/Free Full Text]

This article has been cited by other articles:

				Y J. Woo, T. J Grand, G. P Liao, and C. M Panlilio Off-pump revascularization for significant left ventricular dysfunction. Asian Cardiovasc Thorac Ann, August 1, 2006; 14(4): 306 - 309. [Abstract] [Full Text] [PDF]

				A. J. Rastan, J. I. Eckenstein, B. Hentschel, A. K. Funkat, J. F. Gummert, N. Doll, T. Walther, V. Falk, and F. W. Mohr Emergency Coronary Artery Bypass Graft Surgery for Acute Coronary Syndrome: Beating Heart Versus Conventional Cardioplegic Cardiac Arrest Strategies Circulation, July 4, 2006; 114(1_suppl): I-477 - I-485. [Abstract] [Full Text] [PDF]

				F. W. Sellke, J. M. DiMaio, L. R. Caplan, T. B. Ferguson, T. J. Gardner, L. F. Hiratzka, E. M. Isselbacher, B. W. Lytle, M. J. Mack, J. M. Murkin, et al. Comparing On-Pump and Off-Pump Coronary Artery Bypass Grafting: Numerous Studies but Few Conclusions: A Scientific Statement From the American Heart Association Council on Cardiovascular Surgery and Anesthesia in Collaboration With the Interdisciplinary Working Group on Quality of Care and Outcomes Research Circulation, May 31, 2005; 111(21): 2858 - 2864. [Abstract] [Full Text] [PDF]

				M. I. Stallwood, A. D. Grayson, K. Mills, and N. D. Scawn Acute renal failure in coronary artery bypass surgery: independent effect of cardiopulmonary bypass Ann. Thorac. Surg., March 1, 2004; 77(3): 968 - 972. [Abstract] [Full Text] [PDF]

				D. L. Ngaage Off-pump coronary artery bypass grafting: the myth, the logic and the science Eur. J. Cardiothorac. Surg., October 1, 2003; 24(4): 557 - 570. [Abstract] [Full Text] [PDF]

				C. Muneretto, G. Bisleri, A. Negri, J. Manfredi, M. Metra, S. Nodari, and L. Dei Cas Off-pump coronary artery bypass surgery technique for total arterial myocardial revascularization: a prospective randomized study Ann. Thorac. Surg., September 1, 2003; 76(3): 778 - 783. [Abstract] [Full Text] [PDF]

				D J Wheatley Protecting the damaged heart during coronary surgery Heart, April 1, 2003; 89(4): 367 - 368. [Full Text] [PDF]

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Hani Shennib Jean F. Morin Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Shennib, H. Articles by Morin, J. F. Search for Related Content PubMed PubMed Citation Articles by Shennib, H. Articles by Morin, J. F. Related Collections Minimally invasive surgery