09. tbl. 98. árg. 2012
Outcome of myocardial revascularisation in Iceland
Introduction: In Iceland over 3500 coronary artery bypass operations have been performed, both On-Pump, using cardiopulmonary bypass and Off-Pump, surgery on a beating heart. The aim was to study their outcome.
Material and methods: This was a retrospective study on 720 consecutive patients who underwent surgical revascularisation at Landspítali – The National University Hospital of Iceland between 2002-2006; 513 On-Pump and 207 Off-Pump patients. Complications and operative mortality (<30 days) were compared between the groups and predictors of survival identified using multivariate analysis.
Results: The number of males was significantly higher in the On-Pump group, but other risk factors of coronary artery disease, including age and high body mass index, were comparable, as were the number of distal anastomoses and EuroSCORE. The Off-Pump procedure took 25 minutes longer on average and chest tube output was significantly increased, but the amount of transfusions administered was similar. The rate of minor complications was higher in the On-Pump group. Of the major complications, stroke rates were similar in both groups (2%) but the rate of reoperation for bleeding was higher in the On-Pump group. Mean length of hospital stay was one day longer for On-Pump patients but operative mortality was similar for both groups (4% vs. 3%, p=0.68) as was 5 year survival (92% in both groups). In multivariate analysis both EuroSCORE and age predicted outcome of operative mortality and long term survival but type of surgery (On-Pump vs. Off-Pump) was not a predictive variant.
Conclusions: Outcome of myocardial revascularisation in Iceland is good as regards operative mortality and long term survival. This applies to both conventional On-Pump and Off-Pump procedures.
Sigurjonsson H1,2, Helgadottir S1, Oddsson S1, Sigurdsson M1,2, Geirsson A1, Arnorsson Th1, Gudbjartsson T1,2
1Department of Cardiothoracic Surgery, Landspítali – The National University Hospital of Iceland, 2Faculty of Medicine, University of Iceland, Reykjavík, Iceland
Table I. Number of coronary artery revascularization procedures in Iceland 2002-2006 and ratio of Off-Pump procedures. For comparison the number of coronary angiographies in Iceland and the number of percutaneous coronary intervention (PCI) procedures during the same period is shown. Number of (%).
| Year | 2002 | 2003 | 2004 | 2005 | 2006 | Total |
| Coronary angiography | 1493 | 1630 | 1497 | 1674 | 1526 | 7820 |
| - Balloon angioplasty | 568 (38%) | 624 (38%) | 556 (37%) | 636 (38%) | 610 (40%) | 2994 (38%) |
| - Stent | 474 (32%) | 531 (33%) | 468 (31%) | 570 (34%) | 533 (35%) | 2576 (33%) |
| Coronary artery bypass | 153 | 139 | 133 | 156 | 139 | 720 |
| - On-Pump | 117 (76%) | 103 (74%) | 85 (64%) | 107 (69%) | 101 (73%) | 513 (71%) |
| - Off-Pump | 36 (24%) | 36 (26%) | 48 (36%) | 49 (31%) | 38 (27%) | 207 (29%) |
PCI: Percutaneous coronary intervention
Table II. Patient demographics for OPCAB and CABG patients that underwent coronary artery bypass grafting at Landspitali University Hospital between 2002 and 2006. Number (%) if not otherwise stated.
| Variable |
All patients n = 720 |
Off-Pump n = 207, % |
On-Pump n = 513, % |
p-value |
| Age, mean, years . ± stdv. | 66.4 | 66.4±9.2 | 66.4±9.3 | 0.95 |
| Male sex, | 591 (82) | 160 (77) | 431 (84) | 0.04 |
| Risk factors for coronary artery disease | ||||
| Hypertension | 443 (60) | 130 (61) | 313 (63) | 0.73 |
| Diabetes | 109 (15) | 29 (14) | 80 (16) | 0.67 |
| Dyslipidemia | 421 (58) | 120 (58) | 301 (58) | 0.93 |
| Smoker, current | 174 (24) | 45 (22) | 129 (25) | 0.37 |
| Body mass index (kg/m2 ) | 28,0 | 28.2 ± 4.2 | 27.9 ± 4.1 | 0.37 |
| Preoperative medication(< 5 days from surgery) | ||||
| ASA | 513 (71) | 150 (72) | 363 (71) | 0.71 |
| Cholesterol lowering statins | 529 (73) | 148 (71) | 381 (74) | 0.50 |
| Betablockers | 482 (67) | 141 (68) | 341 (66) | 0.74 |
| Coronary artery disease 3-vessel | 628 (87) | 176 (85) | 452 (88) | 0.32 |
| Left main stenosis | 152 (21) | 44 (21) | 108 (21) | 0.97 |
| Left ventricular ejection fraction <35% | 59 (8) | 17 (8) | 42 (8) | 0.89 |
| Chronic obstructive pulmonary disease | 55 (8) | 14 (7) | 41 (8) | 0.70 |
| NYHA class III and IV | 499 (69) | 160 (77) | 339 (66) | 0.004 |
| EuroSCORE standard | 4.9 | 5.2±3.5 | 4.8±3.2 | 0.23 |
NYHA = New York Heart Association, ASA = Acetylsalicylacid.
Table III. Operation characteristics, length of stay and mortality for OPCAB and CABG patients in Iceland between 2002 and 2006.
| Variable |
All patients n = 720 |
Off-Pump n = 207, % |
On-Pump n = 513, % |
p-value |
| Acute operation, n (%) | 25 (4) | 10 (5) | 15 (2) | 0.30 |
| Operation time*, min. ± stdv. (range) | 204 |
223 ± 59 (85-460) |
197 ± 47 (90-555) |
<0.001 |
| Number of distal anastomoses, ± stdv. (range) | 3.4 | 3.5 ± 0.9 (1-6) | 3.3 ± 0.8 (1-5) | 0.06 |
| Postoperative bleeding <24hours, ml± stdv.,(range) | 1037 |
1230 ± 740 (230-5620) |
960 ± 1530 (100-31820) |
<0.001 |
| RBC transfusions, units ± stdv., (range) | 2.5 |
2.4 ± 3.7 (0-31) |
2.5 ± 5.5 (0-88) |
0.84 |
| Reoperation for bleeding, % | 42 (5,8) | 9 (4,3) | 33 (6,4) | 0.02 |
| Intensive care unit stay – days, ±stdv. | 2.0 | 1.9 ± 2.7 | 2.1 ± 3.7 | 0.47 |
| Length of hospital stay – days, ±stdv. | 12.1 | 11.3 ± 4.9 | 12.5 ± 6.9 | 0.04 |
| Operative mortality (< 30 days) , n (%) | 23 (3.2) | 8 (3.9) | 15 (2.9) | 0.68 |
*skin-to-skin time, PRC = packed red cells
Table IV. Comparison of minor and major complications in patients undergoing Off-Pump or On-Pump coronary revascularization at Landspitali University Hospital between 2002 and 2006.
| Variable |
All patients n = 720, % |
Off-Pump n = 207, % |
On-Pump n = 513, % |
p-value |
| Major complications | 118 16) | 33 (16) | 85(17) | 0.44 |
| Stroke | 16 (2) | 5 (2) | 11 (2) | 0.79 |
| Deep sternal wound infection | 6 (0.8) | 1 (0.5) | 5 (1.0) | 0.84 |
| Renal injury requiring dialysis | 12 (2) | 3 (1) | 9 (2) | 0.97 |
| Perioperative myocardial infarction | 95 (13) | 23 (11) | 72 (14) | 0.35 |
| Multi organ failure | 23 (3) | 5 (2) | 18 (4) | 0.60 |
| Sternal insufficience | 19 (3) | 3 (1) | 16 (3) | 0.31 |
| Minor complications | 391 (54) | 100 (48) | 291 (58) | 0.05 |
| Atrial fibrillation/flutter | 294 (41) | 80 (39) | 214 (42) | 0.50 |
| Superficial wound infection | 65 (9) | 16 (9) | 49 (10) | 0.53 |
| Pneumonia | 45 (6) | 10 (5) | 35 (7) | 0.41 |
| Urinary tract infection | 27 (4) | 12 (6) | 15 (3) | 0.11 |
Fig. 1. Flow chart of patients included in the study.
Fig. 2a and b. Cox survival graphs. Total- (a) and disease specific survival (b) of patients undergoing coronary artery bypass in Iceland, CABG and OPCAB patients combined, but survival for these groups was comparable. (95% confidence interval shown).
b)