Post-coronary Artery Bypass Graft Patients Research Articles

Percutaneous Revascularization of Grafts versus Native Coronary Arteries in Postcoronary Artery Bypass Graft Patients

In patients with previous coronary artery bypass graft surgery, it is unknown whether better results may be obtained with percutaneous interventions of grafts versus native arteries. The clinical outcomes in 84 patients undergoing percutaneous interventions of either grafts (n = 31) or native arteries (n = 53) were compared. Procedural success rate was 95.3% (96.8% in the graft group vs 94.4% in the native group, P = .3). Mean follow-up was 19 ± 7 months. The incidence of major adverse events was 14.2% (12.9% vs 15.1% in the graft and native groups, respectively; P = .8), mortality rate was 3.5% (6.4% vs 1.8% in the graft and native groups, respectively; P = .3), and target-lesion revascularization was performed in 4.7% (6.4% vs 3.7% in the graft and native groups, respectively, P = .6). In conclusion, both graft or native percutaneous interventions were similar for immediate and midterm clinical outcomes. The relatively low risk need for target-lesion revascularization obtained with both strategies is encouraging.

Abstract 2299: Post-CABG Patients with Non-Revascularizable Coronary Artery Disease - A Population Based Study from Olmsted County, Minnesota

Advances in molecular and cellular biology have supported the development of new therapeutic approaches to limiting ischemia. Most often these approaches target patients with ischemia post coronary artery bypass grafting (CABG). Currently, there are few data available on the incidence and outcomes of such patients. To understand this important patient cohort and to estimate the potential need for new therapies, we performed a population-based study of post CABG patients who underwent coronary and graft angiography for angina from 2001 – 2005. Patients who underwent coronary artery and bypass graft angiography at Mayo Clinic from 2001 – 2005 were identified. Medical records were reviewed to determine indication for angiography, and angiographic analysis was performed in all patients. The study cohort was then followed prospectively until March 1 2008. Among 133,000 residents of Olmsted County, Minnesota, 347 post bypass patients with angina underwent coronary angiography from 2001 – 2005. Of those, 51% (177 patients) received further revascularization (endovascular and surgical) and the remaining 170 patients were managed medically. There was no statistical difference in terms of all cause mortality and cardiac mortality between the group that received further revascularization and the group that did not. Adjusting for age and sex for differences between the Olmsted County population and the US white 2000 population yields a yearly incidence rate of 17.9 (95% CI 14.2–21.6) to 33.2 (95% CI 28.2 – 38.3) patients with non-revascularizable angina following CABG per 100,000 population. There was no difference in all cause or cardiac mortality in post-CABG patients presenting with angina whether they received further endovascular/surgical revascularization or not. We estimate that non-revascularizable coronary artery disease post CABG arises in approximately 50,000 (95% CI 40,000 – 61,000) to 93,000 (95% CI 79,000 – 110,000) patients per year extrapolating to the entire US population as a whole.

Percutaneous Revascularization of Grafts Versus Native Coronary Arteries in Postcoronary Artery Bypass Graft Patients

In patients with previous coronary artery bypass graft surgery, it is unknown whether better results may be obtained with percutaneous interventions of grafts versus native arteries. The clinical outcomes in 84 patients undergoing percutaneous interventions of either grafts (n = 31) or native arteries (n = 53) were compared. Procedural success rate was 95.3% (96.8% in the graft group vs 94.4% in the native group, P = .3). Mean follow-up was 19 +/- 7 months. The incidence of major adverse events was 14.2% (12.9% vs 15.1% in the graft and native groups, respectively; P = .8), mortality rate was 3.5% (6.4% vs 1.8% in the graft and native groups, respectively; P = .3), and target-lesion revascularization was performed in 4.7% (6.4% vs 3.7% in the graft and native groups, respectively, P = .6). In conclusion, both graft or native percutaneous interventions were similar for immediate and midterm clinical outcomes. The relatively low risk need for target-lesion revascularization obtained with both strategies is encouraging.

Use of the ABC Care Bundle to Standardize Guideline Implementation in a Cardiac Surgical Population

A cardiac surgical progressive care unit implemented the ABC's of Cardiovascular Risk Reduction Care Bundle to determine whether the use of a packaged approach to medication prescription and lifestyle counseling would improve adherence to secondary risk-reduction guidelines in postcoronary artery bypass graft patients. A pilot study was carried out to assess changes in adherence to guideline recommendations post-Care Bundle implementation. Findings support using a systematic strategy to improve guideline adherence in this population.

Comparison of dynamic measurements of pulse contour with pulsed heat continuous cardiac output in postoperative cardiac surgical patients

Cardiac output (CO) can be measured using bolus thermodilution via a pulmonary artery catheter (PAC) and as continuous cardiac output (CCO), using pulsed heat thermoditution. Pulse contour cardiac output (PCCO) measures continuous CO by analysis of the arterial waveform after calibration with thermodilution CO. The Pulsion Medical Systems (PiCCO system) achieves this by transpulmonary aortic thermodilution (TDtpa). There is uncertainty regarding the agreement between TDtpa, CCO, and PCCO CO measurements in situations of rapid haemodynamic changes. We studied the agreement of the measures by comparing digital recordings of cardiac index (CI) determined by PCCO and CCO (PCCI and CCI, respectively) made during periods of haemodynamic instability. After ethics committee approval we studied four post-coronary artery bypass graft patients, in the immediate postoperative period. Each patient had a 7.5F CCO catheter (Edwards Lifesciences) and a 5F, 20cm PCCO femoral artery catheter. Digital recordings were obtained for the first 12-18 postoperative hours. Six epochs of instability were identified in the first two to three postoperative hours, and at the commencement of inotropic or vasoactive drugs. Notable features, despite frequent PCCO calibrations, were the marked difference of PCCI compared to CCI. In contradistinction, they tracked very closely during a period of stability. Limitations of both methods were noted. Whilst PCCO responded to rapid change, it developed significant error during haemodynmamic instability and requires frequent recalibration. CCO on the other hand has a considerable time lag in responding to changes in CO. The way a monitor measures CO must be taken into account when using the data in clinical management.

Skeletonized versus pedicled internal mammary artery: impact of surgical technique on post CABG surgery pain

Recent evidence suggests that coronary artery bypass graft (CABG) surgery often results in chronic chest wall pain, termed: 'post CABG pain syndrome' (PCP). Direct injury to intercostal nerves during the surgical procedure was presumed to underlie this syndrome. The aim of this study was to investigate the effect of two harvesting techniques of the internal mammary artery (IMA)-skeletonization (S-LIMA) and pedicle (P-LIMA) on the occurrence and incidence of PCP. A mailed questionnaire enquiring about the presence and characteristics of PCP was sent to all 482 patients who had undergone CABG in our institution in the years 1999-2000. A randomly chosen subgroup of IMA patients reporting PCP were summoned for evaluations of pain localization and intensity, thermal and tactile sensitivity, and disability assessment using recognized tests and indices. Of the 380 responders (S-LIMA: 221, P-LIMA: 125, veins only V-34) 169 (44%) reported having PCP. Its prevalence was similar between the two IMA groups (S-LIMA: 45%, P-LIMA: 50%) but significantly lower in the V group (18%, P=0.003). Physical assessment in the subgroup of 43 IMA patients (S-LIMA: 22, P-LIMA: 21) performed 40.2+/-8.7 months after surgery confirmed equal occurrence of mostly left and midline chest wall neuropathic pain in both IMA groups. No significant differences were found between the two groups in respect to indices of pain intensity, thermal and tactile sensitivity and disability. PCP is a prevalent finding in post CABG patients. The skeletonization technique of IMA harvesting although causing significantly less inner chest wall trauma does not appear to reduce the occurrence of PCP. This finding may imply that ischemic injury rather than direct mechanical injury to the intercostal nerves is the putative mechanism underlying PCP.

Cost-effectiveness of distal embolic protection for patients undergoing percutaneous intervention of saphenous vein bypass graftsResults from the SAFER trial

The goal of this research was to determine the incremental cost and cost-effectiveness of embolic protection in patients undergoing percutaneous revascularization (PCI) of diseased saphenous vein bypass grafts (SVGs). Distal protection using the GuardWire balloon occlusion device has been shown to reduce major ischemic complications in patients undergoing SVG PCI, but the cost-effectiveness of this approach is unknown. We prospectively measured medical resource utilization and cost for 801 patients undergoing SVG intervention who were randomized to distal protection using the GuardWire (n = 406) or conventional treatment (n = 395) in the Saphenous Vein Graft Angioplasty Free of Emboli Randomized (SAFER) trial. Long-term survival and cost-effectiveness were projected based on observed 30-day outcomes and a validated survival model for postcoronary artery bypass graft patients. Compared with conventional treatment, distal protection increased initial procedural costs by ∼$1,600 ($6,326 vs. $4,779, p < 0.001). However, by reducing ischemic complications, distal protection reduced mean length of stay by 0.4 days and other hospital costs by nearly $1,000 ($6,846 vs. $7,811, p = 0.018). As a result, overall initial hospital costs were only $582 per patient higher with distal protection. Based on the observed 30-day cost and outcome differences in the trial, the incremental cost-effectiveness ratio for distal protection was $3,718 per year of life saved and remained <$40,000 per year of life saved in 97.3% of bootstrap simulations (95% confidence interval, $0 to $43,079). For patients undergoing PCI of diseased SVGs, distal protection using the GuardWire system is an attractive use of limited health care resources.

Cost-effectiveness of distal embolic protection for patients undergoing percutaneous intervention of saphenous vein bypass grafts: Results from the SAFER trial

The goal of this research was to determine the incremental cost and cost-effectiveness of embolic protection in patients undergoing percutaneous revascularization (PCI) of diseased saphenous vein bypass grafts (SVGs). Distal protection using the GuardWire balloon occlusion device has been shown to reduce major ischemic complications in patients undergoing SVG PCI, but the cost-effectiveness of this approach is unknown. We prospectively measured medical resource utilization and cost for 801 patients undergoing SVG intervention who were randomized to distal protection using the GuardWire (n = 406) or conventional treatment (n = 395) in the Saphenous Vein Graft Angioplasty Free of Emboli Randomized (SAFER) trial. Long-term survival and cost-effectiveness were projected based on observed 30-day outcomes and a validated survival model for postcoronary artery bypass graft patients. Compared with conventional treatment, distal protection increased initial procedural costs by approximately $1,600 ($6,326 vs. $4,779, p < 0.001). However, by reducing ischemic complications, distal protection reduced mean length of stay by 0.4 days and other hospital costs by nearly $1,000 ($6,846 vs. $7,811, p = 0.018). As a result, overall initial hospital costs were only $582 per patient higher with distal protection. Based on the observed 30-day cost and outcome differences in the trial, the incremental cost-effectiveness ratio for distal protection was $3,718 per year of life saved and remained <$40,000 per year of life saved in 97.3% of bootstrap simulations (95% confidence interval, $0 to $43,079). For patients undergoing PCI of diseased SVGs, distal protection using the GuardWire system is an attractive use of limited health care resources.

Impedance Cardiography : The Next Vital Sign Technology?

To evaluate the following: (1) the intramethod variability of impedance cardiography (ICG) cardiac output (CO) measurements via the latest generation monitor and thermodilution CO measurements (CO-TDs); (2) the intermethod comparison of ICG CO and CO-TD; and (3) comparisons of the intergeneration ICG CO equation to CO-TD, using the latest ICG CO equation, the ZMARC (CO-ICG), and the predecessor equations for measuring the ICG CO of Kubicek (CO-K), Sramek (CO-S), and Sramek-Bernstein (CO-SB). Prospective study. A cardiovascular-thoracic surgery ICU in a community university-affiliated hospital. Post-coronary artery bypass graft patients (n = 53) in whom 210 pairs of CO measurements were made. None. The CO-ICG was determined simultaneously while the nurse was performing the CO-TD. Variability within the monitoring method was better for CO-ICG compared to CO-TD (6.3% vs 24.7%, respectively). The correlation, bias, and precision of the CO-ICG was good compared to CO-TD (r(2) = 0.658; r = 0.811; bias, -0.17 L/min; precision, 1.09 L/min; CO-ICG = 1.00 x CO-TD - 0.17; p < 0.001). A steady improvement in agreement of the previous ICG methodologies compared to CO-TD was observed as follows: (1) CO-K: r(2) = 0.309; r = 0.556; bias, -1.71 L/min; precision, 1.81 L/min; CO-K = 0.78 x CO-TD - 0.45; p < 0.001; (2) CO-S: r(2) = 0.361; r = 0.601; bias, -1.46 L/min; precision, 1.63 L/min; CO-S = 0.80 x CO-TD - 0.36; p < 0.001; and (3) CO-SB: r(2) = 0.469; r = 0.685; bias, -0.77 L/min; precision, 1.69 L/min; CO-SB = 1.03 x CO-TD - 0.95; p < 0.001. The CO-ICG demonstrated the closest agreement to CO-TD. The latest ICG technology for determining CO (CO-ICG) is less variable and more reproducible in an intrapatient sense than is CO-TD, it is equivalent to the average accepted CO-TD in post-coronary artery bypass graft patients, and showed marked improvement in agreement with CO-TD compared to measurements made using previous generation ICG CO equations.

Prognostic factors for atherosclerosis progression in saphenous vein grafts: The postcoronary artery bypass graft (post-CABG) trial

OBJECTIVESThe study was done to assess patients in the Post-Coronary Artery Bypass Graft (Post-CABG) trial to determine prognostic factors for atherosclerosis progression.BACKGROUNDSaphenous vein grafts (SVGs) are effective in relieving angina and, in certain patient subsets, in prolonging life. However, the progression of atherosclerosis in many of these grafts limits their usefulness.METHODSThe Post-CABG trial studied moderate versus aggressive lipid-lowering and low-dose warfarin versus placebo in patients with a history of coronary artery bypass surgery and found that more aggressive lipid lowering was effective in preventing progression of atherosclerosis in SVGs, but warfarin had no effect. Using variables measured at baseline, we sought the independent prognostic factors for atherosclerosis progression in SVGs, employing the statistical method of generalized estimating equations with a logit-link function.RESULTSTwelve independent prognostic factors for atherosclerosis progression were found. In the order of their importance they were: maximum stenosis of the graft at baseline angiography; years post-SVG placement; the moderate low-density lipoprotein–cholesterol (LDL-C) lowering strategy; prior myocardial infarction; high triglyceride level; small minimum graft diameter; low high-density lipoprotein–cholesterol (HDL-C); high LDL-C; high mean arterial pressure; low ejection fraction; male gender; and current smoking.CONCLUSIONSThis study identified Post-CABG patient and SVG characteristics associated with saphenous vein graft atherosclerosis progression. These data provide a basis for rational risk factor management to prevent progression of SVG atherosclerosis.

The electrocardiogram complements a chest radiograph for the early detection of pneumothorax in post-coronary artery bypass grafting patients

The electrocardiogram complements a chest radiograph for the early detection of pneumothorax in post-coronary artery bypass grafting patients

Effects of Aerobic Exercise on the Functional Capacity and Cardiovascular Efficiency of Elderly Post-CABG Patients

This study attempted to determine the effects of 12-week low- and high-intensity aerobic exercise programs on functional capacity and cardiovascular efficiency of elderly post-coronary artery bypass graft (CABG) patients. Time (Timemax). estimated maximum VO2 (VO2max), heart rate (HRmax), systolic blood pressure(SBPmax), estimated mean arterial blood pressure (MABPmax), and rate × pressure product (RPPmax) were assessed during graded exercise tests before and after 12 weeks of low-intensity (65% HRmax) and high-intensity (85% HRmax) exercise. Subjects (n = 92) were placed in either a low-intensity (LIEX), high-intensity (HIEX), or nonexercising control group (CON). LIEX and HIEX showed increases from pre- to postprogram for Timemax and VO2max. LIEX and HIEX showed decreases for SBPmax, MABPmax, and RPPmax. HIEX and LIEX produced greater improvements than CON for these four variables, while HIEX was superior to LIEX. It was concluded that 12 weeks of low- and high-intensity aerobic exercise can increase functional capacity and cardiovascular efficiency in elderly post-CABG patients; however, high-intensity exercise may produce greater improvements than low-intensity exercise.

Monitoring during suctioning.

Nurses should monitor post-coronary artery bypass graft (CABG) patients carefully during suctioning.

Effects of Cardiac Rehabilitation after Coronary Artery Bypass Grafting on Readmissions, Return to Work, and Physical Fitness. A Case-control Study

In a case-control study 49 consecutive post-coronary artery bypass grafting (CABG) patients (10 f, 39 m) participating in a comprehensive rehabilitation programme were compared with 98 individually matched double control patients, receiving standard care. The rehabilitation programme, starting 6 weeks after surgery, consisted of follow-up at a coronary clinic, repeated health education, and physical training in out-patient groups. During the first year after CABG, fewer study group patients were readmitted to hospital (14% vs 32%, p less than 0.01) and on fewer occasions (1.1 vs 2.9, p less than 0.05). Fewer patients used anxiolytic drugs (0% vs 15%, p less than 0.01). At the one year post-CABG exercise test we found in the study group a tendency to a greater increase in work capacity, as compared with the values obtained at the preoperative exercise test (33 vs 25 W ns). There were no differences in the rates of returning to work (59% vs 64%). In a long-term follow-up study (av. 38 months post-CABG) the patients were asked to fill in a questionnaire evaluating perceived physical work capacity and training habits. The study group patients rated their physical work capacity higher, and more patients had continued with regular physical training (66% vs 46%, p = 0.05). There were fewer patients using anxiolytic drugs (9% vs 30%, p less than 0.01). Although the programme did not influence the return to work we conclude that it improved the quality of life of our patients as it entailed fewer readmissions and reduced the use of anxiolytic medication; in addition it promoted physical fitness and training habits.

Postoperative Pulmonary Edema in Postcoronary Artery Bypass Graft Patients: Relationship of Total Serum Protein and Colloid Oncotic Pressures

A blinded, prospective study of 52 consecutive male patients undergoing coronary artery bypass grafting was designed to determine which factors were associated with pulmonary edema (PE) in the postoperative period. PE was demonstrated in 18 patients, but not in the remaining 34 patients. PE correlated with the maximum left atrial pressure (p <.001), but not with the degree of preoperative left ventricular dysfunction as manifested by ejection fraction. PE developed in nine of 18 patients at pulmonary capillary hydrostatic pressures (PCHP) ≤15 mm Hg, defining a population with noncardiogenic PE. Postoperative PE was associated with the degree of intraoperative dilutional hypoproteinemia which occurred to a varying degree in every patient. When the immediate postoperative total serum protein (TSP) was ≤4.0 g/dl, PE developed in 72 percent (13 of 18 patients), but occurred in only 15 percent (five of 34 patients) with levels above 4.0 g/dl. The calculated filtration gradient, reflecting the difference between the colloid oncotic pressure and the PCHP was The best univariate predictor of PE. When this fell to ≤2,100 percent (eight of eight patients) developed PE as compared to 12.5 percent (three of 24) above this value (p <.001). The magnitude of pump-induced, hemodilutional hypoproteinemia is the major cause of PE in patients with normal PCHP.