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Eur J Cardiothorac Surg 1998;13:365-369
© 1998 Elsevier Science NL

Coronary bypass surgery: what is changing?

Analysis of 3834 patients undergoing primary isolated myocardial revascularization

^a Department of Thoracic and Cardiac Surgery, -414-, University Hospital Nijmegen, Nijmegen P.O. Box 9101, 6500, Netherlands
^b Department of Medical Informatics, Epidemiology and Statistics, -152-, University Nijmegen, Nijmegen P.O. Box 9101, 6500, Netherlands

Received 24 November 1997; received in revised form 26 January 1998; accepted 4 February 1998.

Corresponding author. Tel.: +24 3614744; fax: +24 3540129; e-mail: L.Noyez@thchir.azn.nl

	Abstract

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Objective: The patient population undergoing myocardial revascularization has changed during the last few years. Knowledge of these changes, and of the subsequent influence on morbidity and/or mortality is important, not only for up-dating quality control, but also to support decision-making in financial and economical aspects, and in further research concerning coronary artery surgery. Methods: Pre-, per- and postoperative data of 3834 primary isolated coronary bypass operations, January 1987–December 1995 were analyzed. The total group was divided into three time cohorts. Group A: 1987–1989 (n=1292); group B: 1990–1992 (n=1130); and group C: 1993–1995 (n=1412). Results: Mean age increased from 60.4±9.0 (S.D.) years in group A to 62.9±9.9 (S.D.) years in group C (P<0.0005). Patients with insulin-dependent diabetic (P=0.005), uro-nefrological (P=0.002), pulmonary (P<0.0005)and neurological (P=0.003) pathology increased significantly, and there was a significant increase in the use of arterial grafts (P<0.05). Postoperative, hospital mortality remained stable (±2.5%). However, there was a significant increasing percentage of patients with pulmonary (P=0.04), neurological (P=0.02) and uro-nefrological (P<0.0005) problems. Conclusion: During the last few years there has been a trend in myocardial revascularization of older patients, with more coexisting disease. Despite the fact that hospital mortality seems stable, there is an increase in major postoperative morbidity.

Key Words: Myocardial revascularization • Comorbidity • Mortality • Morbidity

	Introduction

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During the last few years, cardiac surgeons, cardiologists and all concerned with patients undergoing coronary bypass artery grafting (CABG) have noted a trend towards surgically treating older, sicker patients who have more complex diseases [1] [2] [3]. There has also been an enormous impact on cardiac surgery with regard to the financial and economical aspects. Health care costs must decrease, and this can be done by decreasing the length of hospital stay. This is most effective in patients who have a low morbidity risk. This policy, however, can be dangerous for the high risk patients: they may become isolated, ‘expensive’ patients, for whom there is no place in our ‘low cost health care’ [2] [3]. Therefore it is important to study the evolutionaty trends in the recent patient population, so that the problems can be identified and the support put in place for decision-making in financial and economical aspects and even in further research concerning coronary artery surgery. The purpose of this study was to outline the changes in the patient population during the last few years.

	Material and methods

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Patients
With the aid of our database, Coronary Surgery Database Radboud Hospital (CORRAD), a registry that stores pre-, per- and postoperative data on all patients undergoing isolated myocardial revascularization, we identified a series of 3834 patients undergoing primary isolated CABG from January 1987 to December 1995. These 9 years are subdivided into three time cohorts of 3 years. Group A (1292 patients) operated between January 1987 and December 1989, group B (1130 patients) operated between January 1990 and December 1992, and group C (1412 patients) operated between January 1993 and December 1995. Table 1 presents the studied variables, however only these with a statistical significance change over time or other importance were further noted in this study.

Emergency operation was defined as an operation involving myocardial infarction, ischemia not responding to medical therapy, or cardiogenic shock. Left main is noted when there was a stenosis of 70% or more.

Postoperatively, mortality is defined as operative, hospital and 30-day mortality. Myocardial infarction as a new postoperative Q wave or T wave accompanied by increased cardiac enzymes (CPK-MB>10%). Pulmonary problems were all infectious and other pulmonary and neurological problems were defined as having a new cerebrovascular accident and/or transient ischaemic attack but also when there was confusion for more than 12 h. Under uro-nefrological problems, postoperative dialysis, renal dysfunction (creatinine150 µmol/l) and eventually other urological problems were noted.

Surgical technique
All patients were operated on using the standard cardiopulmonary bypass technique, aortic and right atrial (two stage) cannulation and hypothermia (28–32°C). Myocardial protection during aortic cross-clamping was performed with an infusion of cold (4°C) St. Thomas’ Hospital cardioplegia until asystole occurred and was maintained by reinfusion of 100 ml/m² of the solution every 25–30 min or earlier, as needed. Over the time there was no significant difference in bypass and aortic-crossclamp time, neither in number of grafts and distal anastomoses. The only surgical change was the statistically significant increase in the use of arterial grafts (group A: 69%; group B: 78%; group C: 89%).

Statistical analysis
The characteristics of patients in groups A, B and C are presented as percentages for dichotome variables and as mean±S.D. for age. Differences in age distribution in the three groups were tested with the F-test (one way analysis of variance) and differences in percentage were tested with the ²-test. Statistical significance was assumed at P0.05 (P=0.000 means P<0.0005).

	Results

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Table 2 presents the preoperative data of the patients. There is a statistical significant increase of the mean age of the patients (P=0.0001) and of the percentage of patients 80 years and older. Also the percentage of patients with insulin-dependent diabetic, uro-nefrological and pulmonary pathology increased significantly. The statistically significant increase in patients with neurological pathology, is a phenomenon of the last 3 years of the study (4.3–7.2%). The percentage of patients with hypertension is different in the three groups but no clear trend is seen.

Postoperatively (Table 3), there is statistically no difference between the three groups concerning mortality, perioperative myocardial infarction and percentage of patients that needed ventilatory support for more than 2 days. The percentage of patients with pulmonary problems seems to be different for the three groups (P=0.04). The percentage of patients with neurological and uro-nefrological problem, increased over the years; this is especially clear for the uro-nefrological problems (P=0.000).

	Discussion

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The statistically significant decrease in patients operated on for single-vessel disease is a result of the increasing number of percutaneous transluminal coronary angioplasties. At the same time the number of patients with a successful angioplasty in their preoperative history increased also significantly. The statistically significant decrease in emergency operations can be partially explained by angioplasty of the culprit lesion to stabilize patients. But also the use of fibrinolytic agents, the use of stents, and probably the use of the intraaortic balloonpump preoperatively (not noted separately in our database) are important here.

Left ventricular function, ejection fraction, is not included as a parameter. In the patient population, the ejection fraction is not routinely calculated, mostly, only for patients with ‘bad’ ventricular function. Because of the missing information in more than 70% of the patients, we did not include this parameter in our study. This is of course a deficit, because an impaired left ventricular function is a strong predictor for postoperative mortality and morbidity.

Of the operative variables, only the use of arterial grafts changed significantly. The increasing use of one or more arterial grafts is of course a surgical decision and a consequence of the superiority of the arterial grafts [7]. Several studies proved already that the use of one, or more, arterial graft(s) did not increase postoperative morbidity and mortality [8] [9].

Postoperatively, there is a slight, just significant (P=0.04) increase of patients with pulmonary problems. The percentage of patients with uro-nefrological and with neurological problems, increased significantly. These two postoperative problems are associated with special care and longer hospital stay [10] [11] [12] [13]. It is important is to note that the neurological problems were defined not only by the occurrence of a new cerebrovascular accident or a transient ischemic attack but also when patients were confused for more than 12 h. Several studies are describing a depressed level of consciousness and/or confusion after CABG as a result of cerebral ischemia, and possible in relation to preoperative neurological events. It must be clear that this patient group has also a prolonged overall hospital stay [12] [13].

This study outlines the trends in patients undergoing primary isolated myocardial revascularization during the last few years using standard cardiopulmonary techniques. The results are good, and prove that mortality can be kept low, in spite of a statistically significant increasing number of older patients as well as associated coexisting diseases. The same trend has been documented by The society of Thoracic Surgeons National Database [14]. The reproducibility, durability and the strive for a complete revascularization are the fundamentals of the standard CABG, and it will be difficult for minimally invasive surgery to improve this overall results [15] [16].

In conclusion, during the last few years, in primary CABG, there has been an increasing number of older patients. Also, there has been an increase in variables, maybe in relation to increasing age, who are or may be strong predictors of postoperative morbidity. A postoperative morbidity is where there is an increasing number of neurological and nefrological problems. Further analysis of this postoperative morbidity in relation to preoperative variables will be essential for a better understanding and for prevention of these ‘expensive’ complications.

	References

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1. Jones ES, Weintraub WS, Craver JM, Guyton RA, Cohen CL. Coronary bypass surgery: is the operation different today?. J Thorac Surg 1991;101:108-115.[Abstract]
2. Magovern JA, Sakert T, Magovern GJ, Benckart DH, Burkholder JA, Liebler GA, Magovern GJ. A model that predicts morbidity and mortality after coronary artery bypass graft surgery. J Am Coll Cardiol 1996;28:1147-1153.[Abstract]
3. Katz NM, Chase GA. Risks of cardiac operations for elderly patients: reduction of age factor. Ann Thorac Surg 1997;63:1309-1314.[Abstract/Free Full Text]
4. Peterson ED, Cowper PA, Jollis JG. Outcomes of coronary artery bypass graft surgery in 24461 patients aged 80 years or older. Circulation 1995;92(Suppl. II):85-91.[Abstract/Free Full Text]
5. Jones RH, Hannan EL, Hammermeister KE, DeLong ER, O'Connor GT, Luepker RV, Parsonnet V, Pryor DB. Identification of preoperative variables needed for risk adjustment of short-term mortality after coronary artery bypass graft surgery. J Am Coll Cardiol 1996;28:1478-1487.[Abstract]
6. Williams DB, Carrillo RG, Traad EA, Wyatt CH, Grahowksi R, Wittels H, Ebra G. Determinants of operative mortality in octogenarians undergoing coronary bypass. Ann Thorac Surg 1995;60:1038-1043.[Abstract/Free Full Text]
7. Loop FD, Lytle BW, Cosgrove DM, Stewart RW, Goormastic M, Williams GW, Leonard P, Golding AR, Gill CG, Taylor PC, Sheldon WC, Proudfit WL. Influence of the internal mammary artery graft on 10-year survival and other cardiac events. New Engl J Med 1986;41:1-6.
8. Cosgrove DM, Loop FD, Lytle BW. Does mammary artery grafting increase surgical risk?. Circulation 1985;72(Suppl II):170-174.[Abstract/Free Full Text]
9. Galbut DL, Traad EA, Dorman MJ, DeWitt PL, Larsen PB, Kurlansky PA, Button JH, Ally JM, Gentsch TO. Bilateral internal mammary artery grafts in reoperative and primary coronary bypass surgery. Ann Thorac Surg 1991;52:20-28.[Abstract]
10. Owen CH, Cummings RG, Timothy LS, Schwab SJ, Jones RH, Glower DD. Coronary artery bypass grafting in patients with dialysis-dependent renal failure. Ann Thorac Surg 1994;58:1729-1733.[Abstract]
11. Laws KH, Merril WH, Hammon JW, Prager RL, Bender HW. Cardiac surgery in patients with chronic renal disease. Ann Thorac Surg 1986;42:152-157.[Abstract]
12. Harrison MJ. Neurologic complications of coronary artery bypass grafting: diffuse or focal ischemia?. Ann Thorac Surg 1995;59:1356-1358.[Abstract/Free Full Text]
13. Redmond JM, Greene PS, Goldsborough MA, Cameron DE, Stuart RC, Sussman MS, Watkins L, Lashinger JC, McKhann GM, Johnston MV, Baumgartner WA. Neurologic injury in cardiac surgical patients with a history of stroke. Ann Thorac Surg 1996;61:42-47.[Abstract/Free Full Text]
14. The Society of Thoracic Surgeons. Data analyses of The Society of Thoracic Surgeons National Cardiac Surgery Database, The 4th Year, Chicago, January 1995
15. Reardon MJ, Espadea R, Letsou GV, Safi HJ, McCollum CH, Baldwin JC. Minimally invasive coronary artery surgery—a word of caution. J Thorac Surg 1997;114:419-420.[Free Full Text]
16. Ancalmo N, Busby J. Minimally invasive coronary artery bypass surgery: really minimal?. Ann Thorac Surg 1997;64:928-929.[Free Full Text]

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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): Luc Noyez Stefan H. Skotnicki Leon K. Lacquet Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Noyez, L. Articles by Lacquet, L. K. Search for Related Content PubMed PubMed Citation Articles by Noyez, L. Articles by Lacquet, L. K.