Cost-effectiveness of minimally invasive coronary artery bypass surgery

Robotic-Assisted Versus Traditional Full-Sternotomy Coronary Artery Bypass Grafting Procedures: A Propensity-Matched Analysis of Hospital Costs

We aim to compare hospital costs of robotic-assisted coronary artery bypass grafting (CABG) versus conventional CABG. All consecutive 1,173 patients who underwent conventional and robotic-assisted CABG between January 2018 and June 2021 were included. After propensity-matching, 267 patients in each group (robotic-assisted vs conventional) were included in the study. Patient selection for each group was decided by a treating surgeon with a heart team based on clinical factors. Syntax score was not assessed. Total costs (direct + indirect hospital costs) of patients who underwent robotic-assisted and conventional CABG were compared. Direct cost expenses included surgical operating time, hospital stay, surgical implants and supplies, catheterization laboratory, pharmacy, radiology and ultrasound imaging, blood bank, cardiology, and so on. Indirect cost expenses included general administration medical records, and so on. Using the propensity-matched groups (n = 267), we summed the total cost by year. Results for 267 propensity-matched patients (each group) evidenced that total conventional CABG costs were $9.5 million (average of $35,580/patient), whereas robotic-assisted CABG costs were $5 million ($18,726/patient). Therefore, the differences between robotic-assisted and conventional CABG costs were $4.5 million ($16,853/patient), favoring robotic-assisted over conventional CABG. Differences in direct and indirect costs were $2.2 million and $1.8 million, respectively. When the cost of the Da Vinci robot was added ($1,200,000), the total cost was $3.3 million ($12,359 × patient) lower in the robotic-assisted CABG group. Multivariate analysis showed that, mainly, the shorter hospital length of stay (7 vs 5 days) accounts for the reduced costs observed in the robotic-assisted CABG group. In conclusion, in a mature practice, robotic-assisted CABG decreases hospital length of stay, leading to reduced hospital costs compared with conventional CABG.

Bridging the simulation-to-real gap for AI-based needle and target detection in robot-assisted ultrasound-guided interventions

BACKGROUND

Artificial intelligence (AI)-powered, robot-assisted, and ultrasound (US)-guided interventional radiology has the potential to increase the efficacy and cost-efficiency of interventional procedures while improving postsurgical outcomes and reducing the burden for medical personnel.

METHODS

To overcome the lack of available clinical data needed to train state-of-the-art AI models, we propose a novel approach for generating synthetic ultrasound data from real, clinical preoperative three-dimensional (3D) data of different imaging modalities. With the synthetic data, we trained a deep learning-based detection algorithm for the localization of needle tip and target anatomy in US images. We validated our models on real, in vitro US data.

RESULTS

The resulting models generalize well to unseen synthetic data and experimental in vitro data making the proposed approach a promising method to create AI-based models for applications of needle and target detection in minimally invasive US-guided procedures. Moreover, we show that by one-time calibration of the US and robot coordinate frames, our tracking algorithm can be used to accurately fine-position the robot in reach of the target based on 2D US images alone.

CONCLUSIONS

The proposed data generation approach is sufficient to bridge the simulation-to-real gap and has the potential to overcome data paucity challenges in interventional radiology. The proposed AI-based detection algorithm shows very promising results in terms of accuracy and frame rate.

RELEVANCE STATEMENT

This approach can facilitate the development of next-generation AI algorithms for patient anatomy detection and needle tracking in US and their application to robotics.

KEY POINTS

• AI-based methods show promise for needle and target detection in US-guided interventions. • Publicly available, annotated datasets for training AI models are limited. • Synthetic, clinical-like US data can be generated from magnetic resonance or computed tomography data. • Models trained with synthetic US data generalize well to real in vitro US data. • Target detection with an AI model can be used for fine positioning of the robot.

Propensity Score Adjusted Comparison of MIDCAB versus Full Sternotomy Left Anterior Descending Artery Revascularization

Objective

Minimally invasive direct coronary artery bypass (MIDCAB) has been proposed as an attractive alternative to full sternotomy (FS) revascularization in isolated left anterior descending (LAD) artery disease not suitable for percutaneous coronary intervention. However, surgeons are still reluctant to perform MIDCAB owing to concerns about early and late outcomes. We aimed to compare short- and long-term outcomes after MIDCAB versus FS revascularization.

Methods

Prospectively collected data from institutional database were reviewed. Data for late mortality were obtained from the General Register Office. MIDCAB was performed in 318 patients, whereas 159 had FS, according to the surgeon's preference, among 477 patients with isolated LAD disease. Inverse propensity score weighting was used to estimate treatment effects on short- and long-term outcomes.

Results

In the propensity score-adjusted analysis, FS revascularization versus MIDCAB was associated increased rate of surgical site infection [4 (2.8%) versus 1 (0.7%); P = 0.04]. The 2 groups did not significantly differ with regard to other complications including operative mortality. Mean length of hospital stay was similar for the 2 groups. After a mean follow-up time of 6.2 years (interquartile range, 3.5–9.7 years), compared to MIDCAB, FS was not associated with an improved late survival (β coef, −1.42; standard error, 1.65; P = 0.39) or risk reduction for repeat revascularization (β coef, 1.22; standard error, 1.41; P = 0.15).

Conclusions

MIDCAB was associated with a trend toward better short-term outcomes and excellent long-term results comparable to FS revascularization. According to these findings, surgeons should not be reluctant to perform MIDCAB in isolated LAD disease.

Surgical pitfalls of minimally invasive direct coronary artery bypass procedure from the viewpoint of a surgeon in the learning curve

Introduction

Minimally invasive direct coronary artery bypass grafting (MIDCAB) offers arterial revascularization of the left anterior descending (LAD) coronary artery especially in lesions unsuitable for percutaneous coronary interventions. By avoidance of sternotomy and cardiopulmonary bypass its invasiveness is less than that of conventional bypass surgery.

Aim

We in this study discuss our surgical experience in the MIDCAB procedure.

Material and methods

Thirteen patients were operated on with the MIDCAB procedure. The inclusion criteria for MIDCAB were pure LAD disease totally occluded or severely stenotic. Patient demographics and preoperative and postoperative data were analyzed.

Results

Mean age of the patients was 60.0 ±8.6 years. Patients’ preoperative and postoperative levels of cardiac CK-MB (creatine kinase MB) were not significantly different (p = 0.993). However, cardiac troponin I (p < 0.001), hemoglobin (p < 0.001) and hematocrit (p < 0.001) were significantly different. No perioperative myocardial infarctions or cerebrovascular accidents were seen. The patients were discharged at a mean day of 4.77 with oral antiaggregant therapy. No mortality was seen in the study population.

Conclusions

Minimally invasive direct coronary artery bypass is associated with few perioperative complications. Minimally invasive direct coronary artery bypass in our experience is a very good option for single vessel LAD disease.

First Turkish Experiences of Assisted Beating-Heart Coronary Artery Bypass Graft with the Impella Microaxial Ventricular Assist Device�

The importance of minimally invasive cardiac operations, performed off-pump, without the support of cardiopulmonary bypass (CPB), is continuously increasing. Complete revascularization of obstructed coronary arteries is needed to obtain a better long-term outcome. Insertion into the left ventricle of an efficient microaxial pump can be useful when targeting an important coronary artery located at posterior wall of the heart in a patient with hemodynamic deficiency. The use of such a device can enable surgeons to avoid conversion from a preplanned off-pump strategy to traditional on-pump coronary bypass surgery. The Impella Microaxial Ventricular Assist Device (VAD) (Abiomed, Aachen, Germany) is a miniature pump with a 7-mm catheter and a flow rate of approximately 2.5-5 L/min. This device can enable cardiovascular surgery to be performed without damaging the left ventricle and causing serious aortic deficiency. Therefore, in patients with serious comorbidity, complete revascularization may be performed off pump, with the heart beating, because of the hemodynamic stability provided with the support of the microaxial intracardiac pump. If required, this pump can also support the heart during the early postoperative period. We report the first assisted beating-heart coronary artery bypass graft surgery performed with the Impella Microaxial VAD in our country. The surgery was performed on 2 patients considered high risk on the basis of EUROSCORE testing.

Long-term follow-up after minimal invasive direct coronary artery bypass grafting procedure: a multi-factorial retrospective analysis at 1000 patient-years

We provide a multi-factorial long-term follow-up following minimal invasive direct coronary artery bypass grafting (MIDCABG) to evaluate the long-term efficacy. From 1996 onwards, 390 patients underwent MIDCABG (follow-up: 30.0+/-11.2 months). We analyzed peri-operative and postoperative complications (<30 days) and we obtained early and late angiography. Cumulative follow-up was 1000 patient-years. Early postoperative mortality was 0.8% and myocardial infarction occurred in 1.3% of all patients. Early postoperative angiography (<30 days) was obtained in 238 patients (66.3%) and revealed patency in 97.5% (232/238) including 211 (88.6%) who had no stenosis, 13 with a <50% stenosis (5.5%) and 8 with a >50% stenosis (3.4%), but a patent graft. Only six patients had a total occlusion (2.5%). In the long-term follow-up (completed 74.6%; 291/390 patients), the overall mortality was 5.8%, whereas only 1.7% died due to cardiac reasons. Myocardial infarction occurred in 3.0%, redo CABG was necessary in 1.3%. Seventy-eight patients had late postoperative angiography (>30 days) of those 93.6% (n=73) had a patent graft: 58 had no stenosis (74.4%), 4 had a <50% stenosis (5.1%) and 11 had a >50% stenosis (14.1%), but a patent graft. Only in five patients (6.4%) the anastomosis was occluded. MIDCABG is a safe procedure with long-term anastomotic patency rates comparable with those of open-chest LIMA-left-anterior descending artery (LAD) bypass.

Simultaneous hybrid coronary revascularization reduces postoperative morbidity compared with results from conventional off-pump coronary artery bypass

OBJECTIVES

Less-invasive options are available for surgical treatment of multivessel coronary artery disease. We hypothesized that stenting combined with grafting of the left anterior descending artery with the left internal thoracic artery through a minithoracotomy (hybrid procedure) would provide the best outcome.

METHODS

Patients with equivalent numbers of coronary lesions (2.8 +/- 0.4) underwent either hybrid (n = 15) or off-pump coronary artery bypass through a sternotomy (n = 30). Early and 1-year outcomes were compared. Blood drawn from the aorta and coronary sinus immediately postoperatively was analyzed for activation of coagulation (prothrombin fragment 1.2 and activated Factor XII), myocardial injury (myoglobin), and inflammation (interleukin 8) by using an enzyme-linked immunosorbent assay. Target-vessel patency was determined by means of computed tomographic angiographic analysis.

RESULTS

The hybrid procedure was associated with significantly shorter lengths of intubation and stays in the intensive care unit and hospital and perioperative morbidity (P < .05). Intraoperative costs were increased but postoperative costs were reduced for the hybrid procedure compared with off-pump coronary artery bypass through a sternotomy. As a result, overall total costs were not significantly different between the groups. After adjusting for potential confounders, assignment to the hybrid group was an independent predictor of shortened time to return to work (t = -2.12, P = .04). Patient satisfaction after the hybrid procedure, as judged on a 6-point scale, was greater versus that after off-pump coronary artery bypass through a sternotomy. Finally, the hybrid procedure showed significantly reduced transcardiac gradients of markers of coagulation, myocardial injury, and inflammation and a trend toward significant improvement in target-vessel patency.

CONCLUSIONS

Perhaps because of reduced myocardial injury, inflammation, and activation of coagulation, patients undergoing the hybrid procedure had better perioperative outcomes and satisfaction, with excellent patency at 1 year's follow-up. These promising preliminary findings warrant further investigation of this procedure.

Surgical treatment of coronary multivessel disease

Coronary artery bypass grafting has had a significant impact on the treatment of angina, and has been the 'gold standard' since 1969. Its use and efficacy has been increased by revascularization in cardiac arrest and the use of the internal mammary artery. In parallel, catheter techniques have evolved by means of balloon dilatation and additional stenting. This has effected the referral to surgery despite the development of new arterialization techniques and minimally invasive surgery. As competing techniques, an acceptable equilibrium between surgery and stenting will be found within the next years.

Impact of Off-Pump Coronary Artery Bypass Surgery on Postoperative Bleeding: Current Best Available Evidence

Cardiopulmonary bypass (CPB) is a prerequisite for open-heart surgery, and is a procedure routinely used. CPB exposes blood to artificial surfaces, to mechanical trauma from the pump, to alterations in temperature, and to dilution with fluids, whole blood, plasma products, and drugs, and leads to the activation of platelets, coagulation, and fibrinolysis. Coagulopathy during cardiac surgery with CPB results in impairment in hemostasis and subsequently higher morbidity and mortality. Recent advances in surgical techniques and postoperative management have aimed at reducing postoperative morbidity and mortality. Off-pump coronary artery bypass (OPCAB) surgery is one such advance that attempts to avoid the deleterious effects of extracorporeal circulation by performing myocardial revascularization without CPB. Emerging evidence from several randomized controlled trials (RCTs) as well as large registries such as the Society of Thoracic Surgeons (STS) database suggests that OPCAB reduces the postoperative morbidity and mortality. This review article attempts to evaluate the current best available evidence from RCTs on the impact of OPCAB on postoperative bleeding and transfusion requirements.

Off-pump coronary artery bypass graft surgery: the incidence of postoperative atrial fibrillation

Atrial fibrillation (AF) occurs in one quarter to one third of patients after coronary artery bypass graft surgery (CABG). Conventional CABG uses cardiopulmonary bypass, a process that is itself associated with a systemic vascular inflammatory response that contributes to postoperative morbidity. The avoidance of cardiopulmonary bypass is associated with a significant reduction in the inflammatory response and in the release of markers of myocardial necrosis when compared with conventional CABG. There is speculation that off-pump CABG may reduce the incidence of postoperative AF through reduced trauma, ischaemia, and inflammation. Current data, however, do not emphatically answer the question of whether the incidence of post-CABG AF is reduced by off-pump surgery. The evidence from both observational and randomised studies is conflicting and many studies have weaknesses in design, conduct, or interpretation. It remains an attractive hypothesis that postoperative AF is reduced by off-pump CABG but more robust data are required.

A comparison of bleeding and transfusion in patients who undergo coronary artery bypass grafting via sternotomy with and without cardiopulmonary bypass

OBJECTIVE

To determine whether there is a difference between on-pump cardiopulmonary bypass (CABG) and off-pump coronary artery bypass grafting (OPCAB) without heparin reversal with regard to bleeding, transfusion requirements, and incidence of surgical re-exploration of the mediastinum.

DESIGN

Retrospective chart review.

SETTING

A large academic medical center.

PARTICIPANTS

Two hundred adult patients undergoing cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred CABG patients were compared with 100 OPCAB patients. Statistical significance was measured with P values of <or=0.05. The heparin was not reversed in the OPCAB patients. CABG patients received more intraoperative allogeneic red blood cells (median 250 mL v 0 mL, p = 0.002), intraoperative autotransfusion (IAT) (550 mL v 425 mL, p = 0.001), platelets (9% v 1%, p = 0.009), and less albumin (0 mL v 250 mL, p = 0.001) than OPCAB patients. Postoperatively, CABG patients were more likely to receive fresh-frozen plasma (19% v 8%, p = 0.03) and less likely to receive IAT than the OPCAB group. During the initial 4-hour postoperative period, OPCAB patients exhibited greater blood loss via chest tube (290 mL v 385 mL, p = 0.003); however, at 12 hours and 24 hours postoperatively, there was no statistical difference in blood loss between the 2 groups. There were no statistically significant differences in surgical re-exploration of the mediastinum between the CABG and OPCAB groups.

CONCLUSION

Despite not reversing the heparin at the end of the OPCAB surgery, OPCAB surgery was associated with an overall reduction in allogeneic transfusion requirements.

Intracardiac left ventricular support in beating heart, multi-vessel revascularization

BACKGROUND

Less invasive operation procedures without support of extracorporeal circulation are becoming increasingly important. A basic requirement for good long-term results in such cases is, however, the complete revascularization of the affected coronary vessels. The unsatisfactorily high conversion rate from bypass operations originally planned as off-pump to conventional operations with heart-lung machines, because of the failure to reach the target vessels on the rear wall of the heart through hemodynamic instability led to investigation of the efficiency of a microaxial pump (Impella elect) placed in the left ventricle.

METHODS

In a prospective project 15 of 38 consecutive patients selected for coronary revascularization with beating heart had a micro pump transaortically implanted in the left ventricle to support the heart during the operation with a flow rate of 2.5 to 3.9 l/min.

RESULTS

With 8 of 23 patients operated on without pump support, the operation had to be converted to conventional methods with a heart-lung machine. Only one patient out of the left-ventricle-supported group had to be further operated on conventionally because of a deep intramyocardial positioned left anterior descending coronary artery (LAD) (p < 0.05). The investigated laboratory parameters, especially creatine kinase (CK), CK-MB isoenzyme, and clotting showed no significant difference. There tended to be a higher blood loss recorded with the pump-supported patients.

CONCLUSION

In summary, it appeared that the application of a left ventricular coaxial pump with comparable results seemed to make possible complete revascularization in nearly all patients.

A comparison of on-pump and off-pump coronary bypass surgery in low-risk patients

BACKGROUND

The performance of coronary bypass surgery without cardiopulmonary bypass ("off pump") may reduce perioperative morbidity and costs, but it is uncertain whether the outcome is similar to that involving the use of cardiopulmonary bypass ("on pump").

METHODS

In a multicenter, randomized trial, we randomly assigned 139 patients with predominantly single- or double-vessel coronary disease to on-pump surgery and 142 to off-pump surgery. Cardiac outcome and cost effectiveness were determined one year after surgery. The uncertainty surrounding the cost-effectiveness ratio (cost differences per quality-adjusted year of life gained) was addressed by bootstrapping.

RESULTS

At one year, the rate of freedom from death, stroke, myocardial infarction, and coronary reintervention was 90.6 percent after on-pump surgery and 88.0 percent after off-pump surgery (absolute difference, 2.6 percent; 95 percent confidence interval, - 4.6 to 9.8). Graft patency in a randomized subgroup of patients was 93 percent after on-pump surgery and 91 percent after off-pump surgery (absolute difference, 2.0 percent; 95 percent confidence interval, - 6.5 to 10.4). On-pump surgery was associated with $1,839 in additional direct costs per patient ($14,908 vs. $13,069--a difference of 14.1 percent) and an increase in quality-adjusted years of life of 0.83 as compared with 0.82 (difference, 0.01 year; 95 percent confidence interval, - 0.03 to 0.04). Off-pump surgery was more cost effective than on-pump surgery in 95 percent of bootstrap estimates.

CONCLUSIONS

In low-risk patients, there was no difference in cardiac outcome at one year between those who underwent on-pump bypass surgery and those who underwent off-pump surgery. Off-pump surgery was more cost effective.

Current trends and technique in OPCAB surgery

BACKGROUND AND AIM OF THE STUDY

Aging of the population, increased surgical risk, and technical improvement have contributed to the recent revival of off pump coronary artery bypass surgery (OPCAB). We present our experience with the systematic use of this technique.

METHODS

Between September 1996 and June 2000, 500 OPCAB procedures were performed at the Montreal Heart Institute (95% of all procedures during time frame, single surgeon). Contraindications were unstable hemodynamics, intramyocardial left anterior descending artery, and reoperation with extensive adhesions. Stabilization was achieved with pericardial sutures and mechanical compression. Surgical strategy was to first bypass the culprit lesion. Anesthetic management consisted of adequate fluid loading and minimal use of alpha-agonist. This cohort was compared to a contemporary cohort of 1,444 patients operated with cardiopulmonary bypass (CPB).

RESULTS

Demographics and risk factors were comparable for all. OPCAB patients received more grafts (3.1 +/- 0.9 vs 2.9 +/- 0.7, p = 0.006), conversion rate was low (0.4%), and complete revascularization was achieved in 93%. Operative mortality and perioperative myocardial infarction were comparable in both groups. Transfusion need, CK-MB count, postoperative use of intra-aortic balloon pump, and creatinine increase were less significant in OPCAB. Postoperative hemorrhage, atrial fibrillation, prevalence of cerebrovascular accident, and hospital stay were comparable for both groups. These results are comparable to those currently reported in the literature.

CONCLUSION

OPCAB surgery in the current era has established its safety and short-term efficacy although long-term clinical results are still warranted. Considering the changing pattern in surgical practice, OPCAB surgery should remain a therapeutic option in modern cardiac surgery.

Is Off-pump Coronary Artery Bypass Graft Surgery Cost-Saving?

One of the challenges in comparing the cost of off-pump coronary artery bypass surgery to conventional coronary artery bypass graft surgery with cardiopulmonary bypass is that most data are from observational studies, not randomized controlled trials. Thus, cost differences observed between groups may not be attributable to the difference in surgical technique, but to the underlying patient characteristics that ultimately led the patient to be selected to receive one procedure or another. The purpose of this study was to control for patient selection effects in observational data and estimate reductions in costs and length of stay attributable to the off-pump coronary artery bypass procedure. We studied 1172 patients (245 off-pump coronary artery bypass and 927 coronary artery bypass graft) undergoing coronary bypass graft surgery via a median sternotomy at the Lehigh Valley Hospital between January 1, 1999 and June 30, 2000. Propensity scores were used to match patients who received off-pump coronary artery bypass surgery to similar coronary artery bypass graft surgery patients. Logistic regression was used to estimate propensity scores and select 181 patients from the coronary artery bypass graft group for comparison to patients in the off-pump coronary artery bypass group. Statistical comparisons of continuous outcomes were made using the Student t test after a transformation to natural log scale to correct skewness. Patients in the off-pump group tended to be treated by surgeons with more experience with off-pump surgery (p=0.0001), relatively older (p-0.001), had fewer diseased vessels (p=0.0001), did not have previous coronary artery bypass graft surgery (p=0.01), and had elective (p=0.0002) or urgent (p=0.002) surgery rather than emergent or salvage surgery. Propensity score matched coronary artery bypass graft patients had significantly longer total LOS (p=0.02), postoperative length of stay (p=0.03), and total costs (p=0.016) than patients who underwent off-pump coronary artery bypass surgery. After correcting for selection effects, off-pump coronary artery bypass surgery was associated with 12% lower total costs, 14% fewer total and postoperative hospital days. This suggests that coronary artery bypass surgery without cardiopulmonary bypass is cost-saving at a large academic community medical center. Future research should consider whether off-pump coronary artery bypass surgery is also cost-effective.

Off-pump coronary artery surgery

Cardiopulmonary bypass has several associated deleterious effects that include a systemic inflammatory response, coagulopathy, central nervous system complications and a variable degree of end-organ damage. The recent upsurge in interest in "beating-heart" surgery attempts to avoid these deleterious effects. Advances in surgical technique, such as the use of intracoronary shunts and the Octopus retractor, have made beating-heart surgery a reality. The challenges for the anaesthetist are greater than for coronary artery surgery using cardiopulmonary bypass, and whilst some advantages are proven, such as the lack of the inflammatory response and the decreased need for blood or blood products, others have yet to be proved and there is a need for further research. The advantages and disadvantages need to be evaluated in randomised studies in order to confirm the safety and efficacy of these new techniques in terms of long-term graft patency and decreased morbidity.

Surgical Approaches to Coronary Artery Disease

In this rapidly evolving era of coronary surgery, technologic advances have allowed the development of new myocardial revascularization strategies. Although conventional coronary artery bypass grafting is being challenged by other promising surgical procedures such as off-pump coronary artery bypass grafting, it remains the gold standard in patients with multivessel disease. Accurate evaluations of these new procedures are ongoing to assess their effectiveness and to define their role in the armamentarium of myocardial revascularization.

Off-Pump Coronary Artery Bypass Surgery: Revival of an Old Technique

The ability to perform surgical procedures on the heart was one of the greatest accomplishments of the 20th century. What was once considered an impossible task has become a routine in daily clinical activity. The in troduction of extracorporeal circulation and myocardial protection strategies opened the doors to what was considered by most an insurmountable barrier— unhin dered access to the coronary circulation and intracar diac structures. In the United States, approximately 85% of coronary artery bypass graft procedures are performed with the use of cardiopulmonary bypass (CPB). CPB was and remains the gold standard for this type of cardiac surgical intervention. Over the years, investigators have struggled to find ways of lessening or eliminating the adverse physiologic effects of CPB. These efforts have focused on pharmacologic interven tion, monitoring procedures, blood gas management, and temperature management. Another way of avoid ing these effects is inherently obvious — eliminate the main source of the problem.

Beating heart surgery or conventional CABG: are neurologic outcomes different?

Although there has been much debate about the causes of neurologic complications associated with coronary artery bypass grafting (CABG), there is good evidence linking such complications with some of the pathophysiologic changes associated with use of conventional cardiopulmonary bypass (CPB). Several studies indicate that it is possible to significantly lower risk of stroke and other central nervous system (CNS) morbidity in patients undergoing CPB for CABG by application of selected techniques and equipment modifications. The resurgence of interest in coronary revascularization by using beating heart surgery (BHS) offers a unique opportunity to evaluate neurologic outcome independent of CPB. Currently, BHS would appear to significantly reduce morbidity in the elderly and to decrease the costs and resource use in coronary revascularization patients. It is hoped that by understanding the mechanisms of CNS injury associated with CABG, techniques can be developed to decrease the risk of neurologic injury associated with coronary revascularization, whether or not CPB is used. Definitive conclusions regarding outcomes after best practice CPB or BHS await large-scale, risk-stratisfied multicenter trials.

Off-pump coronary artery bypass surgery for critical left main stem disease: safety, efficacy and outcome

OBJECTIVES

To determine whether patients with critical left main stem (LMS) coronary artery disease can undergo off-pump coronary artery bypass (OPCAB) surgery safely and successfully.

METHODS

From May 1996 to March 2000 data for patients with critical (> or =50%) LMS stenosis who underwent conventional coronary artery bypass surgery with cardiopulmonary bypass (CCAB) or without (OPCAB) were collected prospectively using the Patient Analysis & Tracking System. A reusable pressure stabilizer, intra-coronary shunts and a single posterior pericardial stitch exposure technique were used in all OPCAB cases. Non-randomized, retrospective data analysis included demographic and preoperative risk factors, operative details, clinical outcome and early follow-up.

RESULTS

During the study period 387 patients with LMS stenosis underwent surgery (OPCAB n=75, CCAB n=312). Groups were similar in terms of preoperative and intraoperative variables although CCAB patients received significantly more grafts per patient (3.1+/-0.73 vs. 2.6+/-0.76, P< or =0.001). Mortality was similar in both groups (OPCAB 1.3% vs. CCAB 2.6%). OPCAB patients when compared to CCAB patients had a lower requirement for postoperative inotropes (12.0% vs. 38.1%, P=0.0001), temporary postoperative pacing (2.7% vs. 10.1%, P=0.02), and blood product transfusion (6.7% vs. 31.4%, P<0.0001), a lower incidence of postoperative chest infection (0% vs. 6.7%, P=0.02) and a slightly reduced postoperative length of stay (7.9+/-5.46 vs. 8.3+/-5.11 days, P=0.01). At 24 months follow-up, CCAB and OPCAB actuarial survival was 94.1+/-1.7% and 97.7+/-2.3%, respectively.

CONCLUSIONS

OPCAB surgery is safe and effective in patients with critical LMS disease.

Coronary artery bypass grafting with cardiopulmonary bypass versus off-pump cardiopulmonary bypass grafting: does eliminating the pump reduce morbidity and cost?

BACKGROUND

Cardiopulmonary bypass (CPB) may contribute to the complications and cost of coronary artery bypass grafting (CABG). Off-pump CABG (OPCAB) allows coronary revascularization without CPB. We hypothesized that OPCAB provides satisfactory graft patency while reducing complications and cost compared with CABG with CPB.

METHODS

We prospectively followed 80 patients undergoing CABG: 40 patients undergoing OPCAB and 40 patients undergoing CABG with CPB. OPCAB patients underwent angiography within 48 hours of surgery to determine early graft patency. Incidence of complications, length of stay, and costs were recorded for each patient. The influence of the number of vessels bypassed was analyzed.

RESULTS

OPCAB patients (n = 40) underwent grafting of 2.7 +/- 0.7 vessels per patient compared with 3.6 +/- 0.8 vessels per patient in the CABG with CPB group (n = 40) (p < 0.0001). Angiography demonstrated 105 of 108 (97%) of grafts were patent in the OPCAB group. Incidence of complications, length of stay, and costs did not differ between the OPCAB and CABG with CPB groups. Number of vessels grafted showed a positive correlation to total costs in both groups.

CONCLUSIONS

While OPCAB provided satisfactory early graft patency, there was no significant difference between OPCAB and CABG with CPB with regard to cost, length of stay, or incidence of complications. In this study, eliminating CPB did not reduce morbidity or cost after CABG.

Clinical outcomes and resource usage in 100 consecutive patients after off-pump coronary bypass procedures

BACKGROUND

Cardiopulmonary bypass initiates a cascade of inflammatory processes that may result in end-organ damage, leading to the increased prevalence of noncardiac complications. Therefore, off-pump coronary artery bypass graft (OP-CAB) procedures have recently been introduced into clinical practice.

METHODS

This study was a case-controlled study that compared the outcomes and cost of 100 consecutive OP-CAB procedures with a control group of 100 contemporary matched conventional coronary artery bypass grafting procedures. All operations were performed by a single surgeon (J.H.L. ) and complete revascularization that used off-pump techniques was achieved with the use of innovative exposure techniques to the lateral and posterior wall vessels.

RESULTS

An average of 3.1 grafts per patient were performed in the OP-CAB group (range, 1-5). The incidence of conversion to conventional coronary artery bypass grafting was 1%. The overall mortality rate was 2.0%. There were no instances of stroke, renal failure, or sternal infections in the OPCAB group. Thus, the OP-CAB group had a shorter length of stay (6.1+/-2.5 versus 7.1+/-3.3 d; P =.003), with a corresponding reduction in variable direct cost per case of 29% (P<.001).

CONCLUSION

Our experience suggests that OP-CAB procedures are feasible for most patients who currently require complete revascularization. It is associated with very a low morbidity rate and may represent the ideal revascularization strategy for patients at high risk for undergoing cardiopulmonary bypass.

Surgical management of heart failure

Surgical therapy for congestive heart failure can offer gratifying results in selected elderly patients. Several trials have shown a survival advantage for surgical revascularization compared with medical therapy in the treatment of ischemic cardiomyopathy. Aortic valve replacement is highly effective in treating elderly patients with heart failure caused by severe aortic stenosis, and stentless aortic valves seem to provide a survival advantage in elderly patients with low-gradient aortic stenosis. Mitral valve repair with or without coronary revascularization has been used successfully in patients with severe mitral regurgitation. Transplantation is a viable but rarely used option for elderly patients with congestive heart failure. Totally implantable ventricular assist devices are an exciting new option for elderly patients with congestive heart failure who are not heart transplantation candidates.

Safety and efficacy of off-pump coronary artery bypass grafting

BACKGROUND

We evaluated the application of the off-pump coronary artery bypass (OPCAB) procedure relative to safety and efficiency as measured by operative mortality postoperative complications and longitudinal outcome.

METHODS

Three hundred and fifty OPCAB patients were compared to 3,171 on-pump or conventional coronary artery bypass (CCAB) patients between January 1, 1997 and December 31, 1998. The groups were divided into three preoperative predicted risk categories: low-risk (0 to 2.59%), medium-risk (2.6 to 9.9%), and high-risk (> or =10%). Society of Thoracic Surgeons National Cardiac Surgery Database definitions and predicted risk group models were utilized to compare all preoperative, intraoperative, and postoperative variables using univariate analysis.

RESULTS

Overall comparison of the immediate outcome of CCAB and OPCAB shows little statistical significance in the variables analyzed. The operative mortality was 3.4% in both groups. When the immediate outcome was compared between groups (CCAB vs OPCAB), as well as individual risk groups (low, medium, and high), similar patterns of operative variables and postoperative complications were observed. The operative mortality in the low-risk group was 1.1% for CCAB and 1.4% for OPCAB; 7% for CCAB and 6% for OPCAB in the medium-risk group; and in the high-risk group 28.5% for CCAB compared to 7.7% for OPCAB group (p = 0.008). Short-term follow-up shows a trend of increased recurring angina and reinterventional procedures in the OPCAB patients.

CONCLUSIONS

Safety for OPCAB is assessed through retrospective data review. Longitudinal follow-up for survival, reintervention, and quality of postoperative document efficacy and patency rates, compared to on-pump procedures, is mandatory. This study documented the immediate safety of the OPCAB procedure. Preliminary findings at 1-year follow-up is an important finding in this study, but it is not conclusive at this time. Long-term longitudinal follow-up is required to assess the future effectiveness of OPCAB.