Acute clinical and financial outcomes of on- versus off-pump coronary artery bypass grafting in octogenarians.

BACKGROUND: Coronary artery bypass surgery in octogenarians is associated with increased postoperative morbidity. Off-pump coronary artery bypass surgery eliminates potential complications of cardiopulmonary bypass, but its use remains controversial. This study aimed to evaluate the clinical and financial impact of off-pump coronary artery bypass surgery compared to conventional coronary artery bypass surgery among this high-risk population. METHODS: Patients ≥80 years undergoing first-time, isolated, elective coronary artery bypass surgery were identified using the 2010-2019 Nationwide Readmissions Database. Patients were grouped into off-pump or conventional coronary artery bypass surgery cohorts. Multivariable models were developed to assess the independent associations between off-pump coronary artery bypass surgery and key outcomes. RESULTS: Of ∼56,158 patients, 13,940 (24.8%) underwent off-pump coronary artery bypass surgery. On average, the off-pump cohort was more likely to undergo single-vessel bypass (37.3 vs 19.7%, P < .001). After adjustment, undergoing off-pump coronary artery bypass surgery was associated with similar odds of in-hospital mortality (adjusted odds ratio 0.90, 95% confidence interval 0.73-1.12) relative to conventional bypass. Additionally, the off-pump and conventional coronary artery bypass surgery groups were comparable in odds of postoperative stroke (adjusted odds ratio 1.03, 95% confidence interval 0.78-1.35), cardiac arrest (adjusted odds ratio 0.99, 95% confidence interval 0.71-1.37), ventricular fibrillation (adjusted odds ratio 0.89, 95% confidence interval 0.60-1.31), tamponade (adjusted odds ratio 1.21, 95% confidence interval 0.74-1.97), and cardiogenic shock (adjusted odds ratio 0.94, 95% confidence interval 0.75-1.17). However, the off-pump coronary artery bypass surgery cohort was linked with an increased likelihood of ventricular tachycardia (adjusted odds ratio 1.23, 95% confidence interval 1.01-1.49) and myocardial infarction (adjusted odds ratio 1.34, 95% confidence interval 1.16-1.55). Furthermore, those undergoing off-pump coronary artery bypass surgery demonstrated reduced odds of non-home discharge (adjusted odds ratio 0.91, 95% confidence interval 0.83-0.99) and a decrement in hospitalization expenditures ($-1,290, 95% confidence interval -$2,370 to $200). CONCLUSION: Off-pump coronary artery bypass surgery was linked with increased odds of ventricular tachycardia and myocardial infarction, but no difference in mortality. Our findings point to the safety of conventional coronary artery bypass surgery in octogenarians. Yet, future work is needed to consider long-term outcomes in this complex surgical cohort.

Long-Term Survival After On-Pump and Off-Pump Coronary Artery Bypass Grafting.

BACKGROUND: Off-pump coronary artery bypass grafting (CABG) may be associated with increased hazard for long-term mortality as compared with on-pump CABG. We sought to evaluate risk-adjusted long-term survival after off-pump and on-pump CABG, particularly among high-volume and low-volume CABG surgeons. METHODS: We evaluated 1,235,089 isolated CABGs (off pump = 209,085; on pump = 1,026,004) performed in Medicare beneficiaries from 2001 to 2015. Long-term hazard for mortality after off-pump versus on-pump CABG was compared with Kaplan-Meier and log-rank analysis among all CABG surgeons as well as among high-volume and low-volume CABG surgeons, before and after inverse probability of treatment weighting to adjust for confounding. RESULTS: Among all surgeons, off-pump CABG was associated with a statistically significant hazard for mortality as compared with on-pump CABG before and after inverse probability of treatment weighting (median survival: off pump 9.8 years vs on pump 10.2 years; difference in median survival -134 days; log-rank P < .001). Cox regression analysis confirmed an interaction between surgeon volume and long-term mortality. The hazard for mortality associated with off-pump CABG was decreased among high-volume surgeons (difference in median survival -84 days; log-rank P < .001) and increased among low-volume surgeons (difference in median survival -240 days; long-rank P < .001). CONCLUSIONS: Off-pump CABG was associated with a significant, but clinically modest, increased hazard for mortality as compared with on-pump CABG. The hazard was reduced when off-pump CABG was performed by high-volume CABG surgeons.

The effects of high-sensitivity C-reactive protein on the clinical outcomes in obstructive sleep apnea patients undergoing off-pump coronary artery bypass grafting.

PURPOSE: To investigate the relationship between obstructive sleep apnea (OSA) severity and high-sensitivity C-reactive protein (Hs-CRP), and their respective impact on the clinical outcomes in patients undergoing off-pump cardiac artery bypass grafting (OPCABG). METHODS: We enrolled consecutive eligible patients listed for elective OPCABG who underwent cardiorespiratory polygraphy before surgery between January 2019 and December 2019 in this prospective observational single-center study. Baseline, intraoperative, and postoperative clinical data were compared between absent-mild and moderate-severe OSA groups. Regression analysis investigated the relationship between Hs-CRP level and severity of OSA, and further assessed the factors influencing postoperative atrial fibrillation, duration of hospitalization, and hospital cost. RESULTS: Patients with moderate-severe OSA accounted for 42.3% (52/123) of the cohort. Partial pressure of carbon dioxide (PCO2), Hs-CRP, apnea hypopnea index (AHI), mean apnea time, maximum apnea time, and oxygen desaturation index ODI ≥ 3% were significantly higher in the moderate-severe OSA group than in the absent-mild OSA group. Left ventricle ejection fraction (LVEF), lowest arterial oxygen saturation (SaO2), and mean SaO2 were significantly lower in the moderate-severe OSA group. Moderate-severe OSA was associated with elevated Hs-CRP level (OR = 2.356, 95% CI 1.101-5.041, P = 0.027). Hs-CRP was an independent risk factor for post-CABG atrial fibrillation (POAF) (OR = 1.212, P = 0.01). Hs-CRP level independently correlated with duration of hospitalization (B = 0.456, P = 0.001) and hospital cost (B = 1.111, P = 0.044). CONCLUSION: Hs-CRP level was closely related to OSA severity and have potential utility in predicting POAF, duration of hospitalization, and hospital costs in patients undergoing OPCABG.

Economic Analysis of Surgical and Interventional Treatments for Patients with Complex Coronary Artery Disease: Insights from a One-Year Single-Center Study.

BACKGROUND Surgical treatment methods for patients with complex coronary artery disease (CAD) who have undergone vascular reconstruction mainly include coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI). The purpose of the study aimed to compare a 1-year follow-up for the patient clinical outcomes and costs between PCI and CABG treatment. MATERIAL AND METHODS There were 840 patients enrolled in this study from July 2015 to September 2016. Among the study participants, 420 patients underwent PCI treatment and 420 patients underwent off-pump CABG. Patients costs were assessed from the perspective of the China healthcare and medical insurance system. EuroQOL 5-dimension 3 levels (EQ-5D-3L) questionnaire was used to evaluate the general health status, and the Seattle Angina Questionnaire (SAQ) was used to assess the disease-specific health status. RESULTS After a 1-year follow-up, the all-cause mortality (P=0.0337), the incidence of major adverse cardiac and cerebrovascular events (P<0.001), and additional revascularization (P<0.001) in PCI group were significantly higher than those in CABG group. Both groups have significant sustained benefits in the SAQ subscale. The CABG group had a higher score on the frequency of angina than the PCI group. In addition, the quality-adjusted life year value of PCI and CABG resulted was 0.8. The average total cost for PCI was $14 643 versus CABG cost of $13 842 (P=0.0492). CONCLUSIONS In the short-term, among the CAD patients with stable triple-vessel or left-main, costs and clinical outcomes are substantially higher for CABG than PCI. Long-term, economic, and health benefits analysis, is warranted.

Blood flow assessment by transit time flow measurement and its prognostic impact in coronary bypass surgery.

BACKGROUND: The competitive coronary flow is influenced by the severity of the stenosis and may affect graft patency. Transit time flow measurement (TTFM) enables intraoperative graft evaluation and cardiac magnetic resonance (MRI) allows for graft evaluation during follow-up. METHODS: Competitive flow and target vessel diameters were determined in 35 patients undergoing off-pump coronary bypass graft surgery (CABG) and correlated to TTFM. Cardiac function, ischemia, and graft flow were evaluated using cardiac MRI during the follow-up period to determine the impact of above-mentioned parameters on graft patency. RESULTS: Competitive flow led to reduced mean graft flow (MGF) and increased pulsatility index (PI) in arterial grafts. This effect to was not observed in veins. Smaller target coronary arteries (<1.5 mm) were associated with reduced MGF, more pronounced in veins, which presented increased PI and shortened diastolic flow fraction (DF). No death and no re-hospitalization for acute coronary syndrome occurred. Borderline values of TTFM (mean MGF 13±4 mL/min; PI 3.8±1) in left internal mammary artery (LIMA) were mainly observed due to increased native anterior descending artery (LAD) flow. These LAD's collateralized occluded right coronaries (RCA). The corresponding LIMA to LAD grafts showed a bypass flow increase at cardiac MRI follow-up. Two graft occlusions occurred: one in LIMA-to-LAD bypass with borderline TTFM, which did not collateralize the RCA and one in a vein graft with borderline TTFM bypassed on a narrow vascular target. CONCLUSIONS: Competitive flow has an impact on arteries contrary to veins. Veins are at risk for occlusion when grafted to smaller targets. Borderline LIMA flow should be considered as potentially dangerous, if satisfactory explanations are missing, e.g. in the absence of a large coronary target without flow competition.

Costs Five Years After Off-Pump or On-Pump Coronary Artery Bypass Surgery.

BACKGROUND: Coronary artery bypass grafting (CABG) is a common surgical treatment for ischemic heart disease. Little is known about the long-term costs of conducting the surgery on-pump or off-pump. METHODS: As part of the Randomized On/Off Bypass follow-up study, we followed 2,203 participants randomized to on-pump (n = 1,099) and off-pump (n = 1,104) CABG for 5 years using Department of Veterans Affairs and Medicare administrative data. We examined annual costs through 5 years, standardized to 2016 dollars, using multivariate regression models, controlling for site and baseline patient factors. RESULTS: In the first year, including the CABG surgery, annual average costs were $66,599 (SE, $1,946) for the on-pump group and $70,552 (SE, $1,954) for the off-pump group. In years 2 to 5, average costs ranged from $15,000 to $20,000 per year. There was no significant difference between on-pump and off-pump across the 5 years. We explored differences among high-risk subgroups (diabetes, chronic obstructive pulmonary disease, peripheral vascular disease, cerebrovascular disease, renal dysfunction, ejection fraction < 35%, over age 70 years), and found no treatment assignment by time interactions, except for a nonsignificant trend in patients with diabetes. CONCLUSIONS: At 5 years, the average costs of off-pump and on-pump CABG patients did not statistically differ. Costs do not favor one approach and the decision should be based on clinical risks, especially in subgroups. Future research is warranted to examine post-CABG costs and outcomes for diabetic patients over time.

Safety, efficacy, and cost-effectiveness of intraoperative blood salvage in OPCABG with different amount of bleeding: a single-center, retrospective study.

BACKGROUND: We sought to evaluate the safety, efficacy, and cost-effectiveness of intraoperative blood salvage (IBS) in off-pump coronary artery bypass grafting (OPCABG) surgery with different amount of bleeding. METHODS: We retrospectively reviewed the medical records of 321 patients who underwent OPCABG between December 2012 and December 2016 at our hospital. Patients treated with IBS or allogeneic blood (AB) transfusions were divided into three groups depending on the amount of bleeding respectively: IBS1 or AB1 group (400-600 ml); IBS2 or AB2 group (600-1000 ml); IBS3 or AB3 group (1000-1500 ml). The intraoperative and postoperative conditions, blood transfusion volume, clinical and hematological outcomes, and total blood transfusion cost were examined. RESULTS: The amount of allogeneic red blood cell (RBC) transfusion in the IBSs groups were significantly lower than that in the ABs groups (P < 0.01). Furthermore, drainage volume 24 h post-surgery (P < 0.05) and white blood cell count (WBC) 2 day post-surgery (P < 0.01) in IBS3 group were significantly higher compared with the AB3 group. Additionally, when IBS cost was 230 USD per set, the total blood transfusion cost in the IBSs groups was significantly higher than that in the ABs groups (P < 0.01); however, when 199 or 184 USD, only the IBS1 group, rather than IBS2 or IBS3, showed significantly higher cost of the total blood transfusion compared with the AB1 group (P < 0.05). CONCLUSIONS: When the amount of bleeding was 600-1000 ml, IBS can significantly reduce the demand for allogeneic blood, and has no direct adverse effects on coagulation function and recuperation, and is cost-effective in OPCABG.

Cost-effectiveness of on-pump and off-pump coronary artery bypass grafting for patients with coronary artery disease: Results from the MASS III trial.

BACKGROUND: Recent trials have reported similar clinical outcomes between on-pump and off-pump coronary artery bypass graft (CABG). However, long-term cost-effectiveness of these strategies is unknown. METHODS: A prespecified economic study was performed based on the MASS III trial. Costs were estimated for all patients based on observed healthcare resource usage over a 5-year follow-up. Health state utilities were evaluated with the SF-6D questionnaire. Cost-effectiveness was assessed as cost per quality-adjusted life-year (QALY) gained using a Markov model. Probabilistic sensitivity analysis with the Monte-Carlo simulation and cost-effectiveness acceptability curve were used to address uncertainty. RESULTS: Quality of life improved significantly in both groups during follow-up compared with baseline. At 5 years, when comparing on-pump and off-pump CABG groups, no differences were found in cumulative life-years (4.851 and 4.766 years, P = .319) and QALY gained (4.150 and 4.105 QALYs, P = .332). Mean cost in US dollars per patient during the trial did not differ significantly between the on-pump and off-pump groups ($5890.29 and $5674.75, respectively, P = .409). Over a lifetime horizon, the incremental cost-effectiveness ratio of on-pump versus off-pump CABG was $12,576 per QALY gained, which is above the suggested cost-effectiveness threshold range (from $3210 to 10,122). In the sensitivity analysis, the probability that on-pump CABG is cost-effective compared to off-pump surgery for a willingness-to-pay threshold of $3212 per QALY gained was <1%. For the $10,122 per QALY threshold, the same probability was 35%. CONCLUSION: This decision-analytic model suggests that on-pump CABG is not cost-effective when compared to off-pump CABG from a public health system perspective.

Assessment of the Procoagulant Activity of Microparticles and the Protein Z System in Patients Undergoing Off-Pump Coronary Artery Bypass Surgery.

To understand the coagulation changes after off-pump coronary artery bypass (OPCAB) surgery, we evaluated the procoagulant activity of microparticles (MPs) and microparticles exposing tissue factor (MPs-TF), together with the levels of total tissue factor (TF), protein Z (PZ), protein Z-dependent protease inhibitor (ZPI), and factor X (FX) before (first day) and 1 week after surgery (seventh day) in plasma samples from 30 patients. Twenty healthy controls were also included. Compared to the controls, patients scheduled for surgery had significantly higher MPs-TF procoagulant activity and lower TF levels ( P = .0006, P = .02, respectively). In the whole cohort, median procoagulant activity of MPs-TF and median levels of TF and ZPI were significantly lower ( P = .02, P = .0003, and P = .004, respectively), while median levels of PZ and FX were significantly higher ( P = .02 and P = .002, respectively) on the seventh day compared to the first day. Our results suggest that OPCAB surgery has a significant effect on the procoagulant activity of MPs-TF and the PZ system.