Angiographic results after minimally invasive coronary bypass grafting using the minimally invasive direct coronary bypass grafting (MIDCAB) approach

Comparing the Effectiveness of Open and Minimally Invasive Approaches in Coronary Artery Bypass Grafting: A Systematic Review

Coronary artery bypass grafting (CABG) is an essential operation for patients who have severe coronary artery disease (CAD). Both open and minimally invasive CABG methods are used to treat CAD. This in-depth review looks at the latest research on the effectiveness of open versus minimally invasive CABG. The goal is to develop evidence-based guidelines that will improve surgical outcomes. This systematic review used databases such as PubMed, MEDLINE, and Web of Science for a full electronic search. We adhered to the PRISMA guidelines and registered the results in the PROSPERO. The search method used MeSH phrases and many different study types to find papers. After removing duplicate publications and conducting a screening process, we collaboratively evaluated the full texts to determine their inclusion. We then extracted data, including diagnosis, the total number of patients in the study, clinical recommendations from the studies, surgical complications, angina recurrence, hospital stay duration, and mortality rates. Many studies that investigate open and minimally invasive CABG methods have shown that the type of surgery can have a large effect on how well the patient recovers and how well the surgery works overall. While there are limited data on the possible advantages of minimally invasive CABG, a conclusive comparison with open CABG is still dubious. Additional clinical trials are required to examine a wider spectrum of patient results.

Reduced Morbidity and Mortality Associated With Minimally Invasive Single-vessel Coronary Artery Bypass Compared With Conventional Sternotomy

OBJECTIVE

We aimed to describe the safety and clinical benefits of minimally invasive, nonsternotomy coronary artery bypass grafting (MICABG) using data from The Society of Thoracic Surgeons (STS) National Database.

BACKGROUND

MICABG has gained popularity, owing to expected lower perioperative morbidity and shorter recovery. Despite this, concerns remain regarding anastomotic quality and the validity of proposed perioperative benefits.

METHODS

We queried the STS National Database for all patients who underwent single-vessel coronary artery bypass grafting (CABG) from January 2014 to December 2016 to compare outcomes of MICABG with conventional CABG. Patients who underwent concomitant or emergent procedures were excluded. Propensity-weighted cohorts were compared by operative approach with adjustment for variability across institutions.

RESULTS

Of 12,406 eligible patients, 2688 (21.7%) underwent MICABG, and 9818 (78.3%) underwent conventional CABG. Propensity weighting produced excellent balance in patient characteristics, including completeness of revascularization, body mass index, and STS predictive risk scores. MICABG was associated with significant reduction of in-hospital mortality [odds ratio (OR)=0.32, absolute reduction (AR)=0.91%, P <0.0001]; 30-day mortality (OR=0.51, AR=0.88%, P =0.001), duration of ventilation (8.62 vs 12.6 hours, P <0.0001), prolonged hospitalization (OR=0.77, AR=1.6, P =0.043), deep wound infection (OR=0.33, AR=0.68, P <0.004), postoperative transfusions (OR=0.52, AR=7.7%, P <0.0001), and STS composite morbidity (OR=0.72, AR=1.19%, P =0.008). Subgroup analysis of only off-pump left internal mammary artery-left anterior descending CABG showed similar findings. Major adverse cardiac events and graft occlusion did not differ between groups.

CONCLUSIONS

MICABG is associated with lower mortality and perioperative morbidity compared with conventional sternotomy CABG. MICABG may have a role in treating single-vessel disease.

Angiographic Outcomes for Arterial and Venous Conduits Used in CABG

Coronary artery bypass grafting is the most commonly performed cardiac surgical procedure. Conduit selection is crucial to achieving early optimal outcomes, with graft patency being likely the main driver to long-term survival. We present a review of current evidence on the patency of arterial and venous bypass conduits and of differences in angiographic outcomes.

Off-Pump Coronary Artery Bypass Surgery

Off-pump coronary artery bypass surgery has been adopted enthusiastically worldwide. However, despite more than 6 years’ experience and refinement, many surgeons use it only sporadically and some hardly at all. This reluctance persists despite support for the procedure because of the lack of properly designed risk models and/or randomized studies. Although it has not been overwhelmingly shown that off-pump surgery is superior to the conventional on-pump procedure, the technique has its place in our specialty. It has been shown to be better for noncritical end points in selected patients in the hands of selected surgeons. That there are differences in surgical skill among surgeons is something we all know but rarely discuss in public. Until now, disparities in skill have been most salient with uncommon and extraordinarily challenging operations. Perhaps the off-pump procedure should be regarded as the “challenging” aspect of coronary artery bypass surgery, and self-restraint may need to remain in force if we are to continue to achieve the highest level of clinical excellence.

Six-month healing of the nonocclusive coronary anastomotic connector in an off-pump porcine bypass model

OBJECTIVE

This pilot study evaluates the anastomotic healing of the Excimer Laser Assisted Nonocclusive Anastomosis coronary connector at 6 months in a porcine off-pump coronary artery bypass (OPCAB) model.

METHODS

Left internal thoracic artery to left anterior descending coronary artery bypass in two animals and left internal thoracic artery to left anterior descending coronary artery and right internal thoracic artery to right coronary artery bypasses in one animal were evaluated intraoperatively and at 6 months. The anastomoses (n = 4) were examined by angiography, intravascular ultrasound, optical coherence tomography, scanning electron microscopy, and histology.

RESULTS

At follow-up, all anastomoses (n = 4) were fully patent (FitzGibbon grade A). Scanning electron microscopy demonstrated complete endothelial coverage of the anastomotic surface, and histology showed minimal streamlining intimal hyperplasia. The in vivo intravascular ultrasound and optical coherence tomography acquisitions confirmed histologic findings. Optical coherence tomography demonstrated 0.06-mm intimal coverage of the intraluminal part of the connector along the full circumference of the anastomosis.

CONCLUSIONS

In this pilot study, the Excimer Laser Assisted Nonocclusive Anastomosis coronary connector showed an excellent healing response on the long-term in the porcine OPCAB model. Hence, this new concept might be a potential alternative to hand-sutured anastomosis in (minimally invasive) OPCAB surgery.

Review of a 13-year single-center experience with minimally invasive direct coronary artery bypass as the primary surgical treatment of coronary artery disease

BACKGROUND AND AIM OF THE STUDY

In this study, we review our experience with 1768 minimally invasive direct coronary artery bypass (MIDCAB) operations. The focus is on long-term outcome with more than 10 years of follow-up.

METHODS

All patients undergoing standard MIDCAB between 1996 and 2009 were included. For all 1768 patients, pre-, intra-, and postoperative data could be completed. Long-term follow-up information about health status, major adverse cardiac and cerebrovascular events (MACCE), and freedom from angina was collected annually via questionnaire or personal contact. Five-year follow-up is available for 1313 patients, and 10-year-follow-up is available for 748 patients. A multivariate Cox regression analysis was performed to determine risk factors for long-term outcome.

RESULTS

Mean age was 63.4 ± 10.8 years, mean ejection fraction was 60.0% ± 14.2%, and perioperative mortality risk calculated by logistic EuroSCORE was 3.8 ± 6.2%. In 31 patients (1.75%) intraoperative conversion to sternotomy was necessary. Early postoperative mortality was 0.8% (15 patients); 0.4% (7 patients) had a perioperative stroke. Seven hundred twelve patients received routine postoperative angiogram, showing 95.5% early graft patency. Short-term target vessel reintervention was needed in 59 patients (3.3%) (11 percutaneous transluminal coronary angioplasty (PTCA)/stent, 48 re-operation). Kaplan-Meyer analysis revealed a 5-year survival rate of 88.3% (95% confidence interval [CI], 86.6% to 89.9%) and a 10-year-survival rate of 76.6% (95% CI, 73.5% to 78.7%). The freedom from MACCE and angina after 5 and 10 years was 85.3% (95% CI, 83.5% to 87.1%) and 70.9% (95% CI, 68.1% to 73.7%), respectively.

CONCLUSIONS

MIDCAB is a safe operation with low postoperative mortality and morbidity. With excellent short-term and long-term results, it is a very good alternative compared to both percutaneous coronary intervention (PCI) and conventional surgery.

Coronary artery bypass grafting without full sternotomy

Coronary artery bypass grafting is performed without full sternotomy in selected patients because it is less invasive. Left internal thoracic artery-left anterior descending artery bypass (LITA-LAD bypass) via a small left anterior thoracotomy is a well established procedure, which achieves good graft patency with low mortality and morbidity rates. Multiple revascularization is possible with a limited lateral thoracotomy or L-figure approach. Axillary-coronary bypass and right gastroepiploic artery-right coronary artery bypass (RGEA-RCA bypass) are alternative methods, especially for redo surgery, in selected patients.

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.

Can 64-Row Computed Tomography Replace Angiography after Coronary Bypass?

Multi-detector (64-row) computed tomography has become an alternative to coronary angiography to diagnose graft occlusion and stenosis after coronary artery bypass. We compared the power of evaluation of multi-detector computed tomography with that of conventional coronary angiography in 60 patients who underwent coronary artery bypass with 135 grafts and 210 graft anastomoses. The diagnostic power of multi-detector computed tomography for graft occlusion was: 100% (2/2) sensitivity, 98.5% (131/133) specificity, 50% (2/4) positive predictive value, and 100% (133/133) negative predictive value; there were no significant differences in rates of occlusion among the different types of graft. The diagnostic power of multi-detector computed tomography for stenosis of the graft anastomosis was: 100% (2/2) sensitivity, 95.1% (194/204) specificity, 16.6% (2/12) positive predictive value, and 100% (194/194) negative predictive value, with no significant differences among grafts. Multi-detector computed tomography permits evaluation of bypass grafts and is much less invasive for the patients.

Seven-Year Follow-up After Minimally Invasive Direct Coronary Artery Bypass: Experience With More Than 1300 Patients

BACKGROUND

Minimally invasive direct coronary artery bypass (MIDCAB) for revascularization of the left anterior descending artery has become a routine operation. Here we present the experience after more than 1300 MIDCAB procedures with up to 7 years of follow-up.

METHODS

All patients undergoing standard MIDCAB between 1996 and 2004 were included. Long-term follow-up information about health status, major cardiac and cerebral adverse events, and freedom of angina was collected annually by a questionnaire or personal contact. Preoperative, intraoperative, and postoperative data could be completed for all 1347 patients. Five-year follow-up was available for 450 patients and 7-year follow-up for 194 patients.

RESULTS

Mean age was 63.2 years (range, 25 to 92 years) and mean ejection fraction was 0.61 +/- 0.14. In 23 patients (1.7%), intraoperative conversion to sternotomy or CPB, or both, was necessary. Early postoperative mortality was 0.8% (n = 11), and 0.4% (n = 5) had a perioperative stroke. A routine postoperative angiogram in 709 patients showed 95.6% early graft patency. Short-term target vessel reintervention was needed 55 patients (4.1%): 10 had percutaneous transluminal coronary angioplasty/stent and 45 had reoperation. A repeat angiogram at the 6-month follow-up was available in 350 patients and demonstrated 94.3% graft patency. Kaplan-Meier analysis revealed a 5-year survival of 91.9% (95% confidence interval [CI], 90.1% to 93.8%) and a 7-year survival of 89.4% (95% CI, 86.7% to 92.1%). The freedom of major adverse events and angina was 89.5% (95% CI, 87.4% to 91.5%) after 5 years and 83.3% (95% CI, 79.0% to 87.5%) after 7 years.

CONCLUSIONS

MIDCAB can be safely performed with low postoperative mortality and morbidity. The excellent short-term and long-term survival as well as freedom from major adverse cardiac and cerebral events and angina compare favorably with stenting and conventional surgery.

Revascularization of Left Anterior Descending Artery With Drug-Eluting Stents: Comparison With Minimally Invasive Direct Coronary Artery Bypass Surgery

BACKGROUND

The proximal left anterior descending artery (LAD) is a challenging area for percutaneous interventions; therefore, coronary artery bypass grafting is often considered and sometimes performed even in patients with single-vessel disease involving the proximal LAD. This study compares mid-term results of LAD revascularization using drug-eluting stents (Cypher) with minimally invasive direct coronary artery bypass grafting (MIDCAB).

METHODS

From May 2002 to December 2003, 376 consecutive patients underwent myocardial revascularization of the LAD, 272 by Cypher and 104 by MIDCAB. After matching for age, sex, and extent of coronary artery disease, two groups of 83 patients each were used to compare the two revascularization modalities. The groups were similar; however, ejection fraction of less than 0.35 was more prevalent in the MIDCAB group and prior percutaneous coronary intervention in the Cypher group.

RESULTS

Thirty-day mortality was 1.1% in the MIDCAB and 0% in the Cypher group. Mean follow-up was 22.5 months. Two late cardiac deaths occurred in the MIDCAB group and one in the Cypher group (p = NS). Angina returned in 35% of the Cypher group and in 8.4% of the MIDCAB group (p < 0.001). There were 14 (16.8%) reinterventions in the Cypher compared with three (3.6%) in the surgical group (p = 0.005). Cox proportional hazard model showed that assignment to the Cypher group was the only independent predictor of reangina (hazard ratio [HR], 6.17, 95% confidence interval [CI], 2.46 to 15.4). Treatment with Cypher was also an independent predictor of reintervention (HR 8.26, 95% CI, 1.68 to 40).

CONCLUSIONS

Despite improved results of percutaneous interventions with Cypher to the LAD, mid-term clinical outcome of patients treated with MIDCAB was better.

Off-Pump Surgery Is Associated With Reduced Occurrence of Stroke and Other Morbidity as Compared With Traditional Coronary Artery Bypass Grafting

Background and Purpose— There is growing enthusiasm for coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB). Although deleterious effects of CPB are known, it remains to be proven that avoiding CPB will result in reduction in morbidity. We sought to determine whether off-pump surgery is associated with reduced occurrence of adverse outcomes as compared with CABG with CPB.

Methods— Studies were identified by searching the MEDLINE, EMBASE and the Cochrane Register 1980 to 2006 (February). We also searched the reference lists of randomized clinical trials (RCT) and reviews to look for additional studies. Study selection: RCTs comparing off-pump surgery to CABG with CPB. No restriction applied on the size of the trial or end point reports. Data extraction: 2 reviewers independently searched for studies, read abstracts and abstracted all data. Data synthesis: combined estimates were obtained using fixed or random effect meta-analyses. Relative risks and risk differences were calculated. Heterogeneity was assessed using χ 2 and I 2 values.

Results— There were 3996 patients enrolled in 41 RCTs (mean age 62, 22% female). No study reported information on race. Off-pump CABG was associated with a 50% reduction in the relative risk of stroke (95% CI, 7% to 73%), 30% reduction in atrial fibrillation (AF; 95% CI, 16% to 43%) and 48% reduction in wound infection (95% CI, 26% to 63%) with no heterogeneity among RCTs. This translated into avoidance of 10 strokes, 80 cases of AF and 40 infections per 1000 CABG. Fewer distal grafts were performed and there was evidence for >10 reinterventions per 1000 with off-pump CABG. Long-term follow-up is not yet reported in the trials.

Conclusions— Off-pump CABG is associated with reduced risk of stroke, AF and infections as compared with CABG with CPB. Evidence should be generalized taking into account RCT enrollment limitations, drawbacks related to training requirements, propensity to perform fewer grafts and likely reinterventions after off-pump surgery.

Results of the Prospective Multicenter Trial of Robotically Assisted Totally Endoscopic Coronary Artery Bypass Grafting

BACKGROUND

Robotic technology has been proven safe and efficacious in the performance of mitral valve repair and atrial septal defect repair. This report describes a Food and Drug Administration-sanctioned multicenter study of the safety and efficacy of the da Vinci system (Intuitive Surgical, Inc, Mountain View, CA) for totally endoscopic coronary artery bypass (TECAB) surgery.

METHODS

Patients requiring left anterior descending (LAD) coronary artery revascularization were eligible. The procedure was performed with femoro-femoral cardiopulmonary bypass (CPB), endoaortic balloon occlusion, and thoracoscopy. All aspects of the procedure were performed with the robotic system, from internal mammary artery harvest to coronary anastomosis.

RESULTS

Ninety-eight patients requiring single-vessel LAD revascularization were enrolled at 12 centers. Thirteen patients (13%) were excluded intraoperatively (eg, failed femoral cannulation, inadequate working space). In 85 patients (69 men, age 58 +/- 10 years) who underwent TECAB, CPB time was 117 +/- 44 minutes, cross-clamp time was 71 +/- 26 minutes, and hospital length of stay was 5.1 +/- 3.4 days. There were five (6%) conversions to open techniques. There were no deaths or strokes, one early reintervention, and one myocardial infarction (1.5%). Three-month angiography was performed in 76 patients, revealing significant anastomotic stenoses (> 50%) or occlusions in 6 patients. Overall freedom from reintervention or angiographic failure was 91%.

CONCLUSIONS

Robotic TECAB was accomplished with no mortality, low morbidity, and angiographic patency and reintervention rates comparable with published data. Although the use of CPB was a limitation of the technique, this experience represents a step toward more advanced procedures, such as multivessel or off-pump TECAB.

Noninvasive Assessment of Off-Pump Coronary Artery Bypass Surgery by 16-Channel Multidetector-Row Computed Tomography

BACKGROUND

Sixteen-channel multidetector-row computed tomography (MDCT), with higher spatial and temporal resolution, enables noninvasive visualization of images with reduced motion artifact and breath-holding time. We compared images of 16-channel MDCT and selective bypass graft angiography among patients who had off-pump coronary artery bypass graft surgery.

METHODS

The study, conducted from April 2003 to March 2004, involved 42 patients who underwent off-pump coronary artery bypass graft surgery. Samples yielded a total of 96 arterial grafts, 5 vein grafts. Sixteen-channel MDCT (LightSpeed Ultra 16; GE Healthcare, Milwaukee, Wisconsin) was performed on each patient using 500-ms or 600-ms rotation time, 0.625-mm slice thickness, and mean scanning time of approximately 24 seconds.

RESULTS

If several sequential anastomoses in one graft existed, each was calculated as a separate graft. Selective bypass graft angiography yielded a patency rate of 97% (155 of 160). Multidetector-row computed tomography enabled detection of 143 of 155 patent grafts and all 5 occluded grafts visualized by selective bypass graft angiography (100% sensitivity and 93% specificity for graft occlusion after exclusion of grafts not evaluated by MDCT). In 149 graft anastomoses of 143 patent grafts viewed by MDCT, 2 significant stenoses were detected by both selective bypass graft angiography and MDCT. Twelve distal anastomoses were not evaluated by MDCT because of metallic clip artifacts. Evaluation possible graft anastomoses were 92%. Sensitivity and specificity for significant stenosis after exclusion of graft anastomoses not evaluated by MDCT were 100% and 99%, respectively.

CONCLUSIONS

High-quality 16-channel MDCT images allowed detection of graft occlusion and significant stenosis of graft anastomosis after off-pump coronary artery bypass graft surgery, demonstrating an alternative tool less invasive than selective bypass graft angiography to assess grafts after surgery.

Intraoperative angiography leads to graft revision in coronary artery bypass surgery

BACKGROUND

Graft anastomosis quality in coronary artery bypass surgery can be assessed by intraoperative angiography. The aim of the present study was to quantify the on-table revision rate initiated by intraoperative angiography.

METHODS

Intraoperative angiography was carried out in 186 patients undergoing coronary artery bypass surgery, with a total of 427 grafts. The operation was performed on-pump in 34%, off-pump through a sternotomy in 49%, and as a minimally invasive direct coronary bypass grafting (MIDCAB) procedure in 17%. The angiography was performed intraoperatively while the patients were still in general anesthesia, with the possibility for on-table revision. Follow-up angiography was carried out after a mean of 346 days.

RESULTS

Eighteen of 427 grafts (4.2%) were revised due to the findings at intraoperative angiography. Revision rate after on-pump surgery was 1.1%, after off-pump through a sternotomy 6.4%, and after MIDCAB 6.5%. In 6 patients the lesions were located at the distal anastomoses and in 12 patients in the conduit. All but one was successfully revised, and at 1-year follow-up all these 17 grafts were patent.

CONCLUSIONS

Intraoperative angiography saves a potential number of grafts that otherwise could have been occluded. An increased implementation of intraoperative quality assessment in coronary artery bypass surgery can lead to improved outcome.

Clinical and six-month angiographic evaluation of coronary arterial graft interrupted anastomoses by use of a self-closing clip device: a multicenter prospective clinical trial

OBJECTIVES

To evaluate the safety and effectiveness of a self-closing surgical clip with an interrupted technique in left internal thoracic artery to left anterior descending artery bypass grafting.

METHODS

Eighty-two patients were enrolled and treated (February 2000 through August 2001) in a prospective, nonrandomized, multicenter trial. Left internal thoracic artery to left anterior descending artery anastomoses were performed in 60 off-pump coronary artery bypasses (73%), 12 conventional coronary artery bypass grafting (15%), and 10 minimally invasive direct coronary artery bypass (12%) procedures. Angiograms (64 to 383 days, mean 200 days) were obtained on 63 patients (77%). Qualitative and quantitative angiographic assessment was performed by an independent core laboratory.

RESULTS

The self-closing surgical clip was used for 82 left internal thoracic artery to left anterior descending artery interrupted anastomoses without the requirement for knot tying or primary suture management. Minimum left internal thoracic artery to left anterior descending artery anastomosis time was 3 minutes. There was one perioperative and one late death (both not heart related) and one reexploration for bleeding unrelated to the anastomotic site. FitzGibbon grades were as follows: A (n = 60, 95.2%), B (n = 3, 4.8%) including one kinked left internal thoracic artery, and O (n = 0, 0%). Quantitative analysis (n = 57) showed mean lumen diameters of left internal thoracic artery proximal to the anastomosis of 2.1 mm, at anastomosis of 2.0 mm, and in the left anterior descending artery distal to the anastomosis of 1.9 mm. The average ratio of the anastomosis to the left anterior descending artery diameter was 1.14 (0.45 to 1.93). Anastomotic stenosis as a percentage of average left internal thoracic artery to left anterior descending artery diameter was -2.3%, comparing favorably with results (23% to 24%) reported from the Patency, Outcomes, Economics, Minimally invasive direct coronary artery (POEM) bypass study.

CONCLUSIONS

The interrupted technique, facilitated by a self-closing anastomotic clip, yields favorable 6-month angiographic results when compared with other published studies.

Use of off-pump and on-pump CABG strategies in current clinical practice: the Clinical Outcomes Assessment Program of the state of Washington

BACKGROUND

The purpose of this study is to assess clinical outcomes and regional differences in the use of on-pump and off-pump CABG in current clinical practice.

METHODS

Between January 1, 1999, and December 31, 2000, there were 10,429 CABG procedures performed in 16 Washington state hospitals, all of which participate in Clinical Outcomes Assessment Program database. This analysis excluded patients with a history of prior CABG as well as those who underwent emergent surgery. After applying these exclusion criteria, 8402 patients (7169 on-pump and 1233 off-pump CABG procedures) were evaluated and presented as both unadjusted and risk-adjusted outcomes.

OUTCOMES

Off-pump CABG constituted 14.7% of all surgical revascularization procedures. These varied enormously among individual centers from an incidence of 0% to 68.9%. The use of off-pump CABG was not associated with a decreased risk of risk-adjusted hospital mortality or stroke, but was associated with a reduction in hospital stay > 7 days (OR 0.62, CI 0.51-0.76), ventilator > 24 hours (OR 0.52, CI 0.34-0.81), dialysis (OR 0.34, CI 0.14-0.86), and RBC transfusion (OR 0.5, CI 0.40-0.61).

CONCLUSIONS

Despite its highly variable use, off-pump CABG seems to be judiciously used in current clinical practice in the State of Washington and is associated with a decrease in morbidity in appropriately selected patients.

Experimental coronary artery occlusion: relevance to off-pump cardiac surgery

Mechanical coronary artery occlusion is required for minimally invasive direct coronary artery bypass and off-pump coronary artery bypass surgery. It is important that the method of occlusion be minimally traumatic. Chronic effects of these methods have never been studied. Temporary occlusion of coronaries utilizing suture snare, silastic loop snare, and bulldog clamp was carried out in 12 Yucatan pigs. Three animals each were sacrificed acutely and at 3, 6, and 12 months. The area of occlusion of each vessel was examined by light microscopy and the degree of damage recorded. In the animals sacrificed acutely, there was more damage using the suture snare than with the other 2 methods, but there was minimal damage at longer intervals. There was slight damage acutely and chronically with the bulldog technique. No damage was seen acutely with the silastic loop technique, but some late damage was found. The techniques of coronary artery dissection and occlusion used for minimally invasive and off-pump bypass surgery may contribute to early postoperative graft occlusion.

Manual control and tracking--a human factor analysis relevant for beating heart surgery

Manual control and tracking are fundamental to human factors and define a metric framework which determines the limits of surgical precision. This review provides a brief analysis of factors that are relevant for targeted motions. Knowing and accepting the limitations of human performance may help to optimize performance in off-pump surgery.

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.

Minimally invasive coronary artery bypass grafting versus percutaneous transluminal coronary angioplasty with stenting in isolated high-grade stenosis of the proximal left anterior descending coronary artery: six months' angiographic and clinical follow-up of a prospective randomized study

OBJECTIVE

We sought to compare minimally invasive coronary artery bypass grafting (surgical intervention) with percutaneous transluminal coronary angioplasty with primary stenting (stenting) in patients having an isolated high-grade stenosis (American College of Cardiology/American Heart Association classification type B2 or C) of the proximal left anterior descending coronary artery. At 6 months, both procedures were compared on the basis of quantitative angiography and clinical outcome.

METHODS

Both treatments were compared in a single-center, prospective, randomized study. The primary end point of this study was quantitative angiographic outcome at 6 months. The secondary end point was 6-month clinical outcome. Statistical analysis was performed in accordance with the intention-to-treat principle.

RESULTS

From March 1997 to September 1999, patients with angina pectoris caused by an isolated high-grade stenosis of the proximal left anterior descending coronary artery were randomly assigned to surgical intervention (n = 51) or stenting (n = 51). At 6 months, quantitative coronary angiography showed an anastomotic stenosis rate of 4% after surgical intervention and a restenosis rate of 29% after stenting (P <.001). Periprocedural events did not significantly differ between surgical intervention and stenting. After surgical intervention, 2 patients died; no patients died after stenting. After 6 months, no significant difference was found for major adverse cardiac or cerebral events and need for repeat target vessel revascularization. After 6 months, return of angina pectoris, physical work capacity, and use of antianginal drugs did not significantly differ between treatments.

CONCLUSIONS

After 6 months, surgical intervention had a significantly better angiographic outcome than stenting in patients with an isolated high-grade stenosis of the proximal left anterior descending coronary artery. Clinical outcome did not significantly differ between treatments.

Off-pump coronary artery bypass grafting: new developments but a better outcome?

Off-pump coronary artery surgery is now performed safely and effectively without cardiopulmonary bypass. This review includes indications, approaches, anaesthetic and haemodynamic management, and compares the occurrence of postoperative complications and multiorgan dysfunction with conventional cardiac surgery.

Combination of minimally invasive coronary bypass and percutaneous transluminal coronary angioplasty in the treatment of double-vessel coronary disease: Two-year follow-up of a new hybrid procedure compared with "on-pump" double bypass grafting

OBJECTIVE

Percutaneous transluminal coronary angioplasty (PTCA) or surgery can be chosen as first-line therapies in multiple-vessel coronary disease. A mammary-to-left anterior descending (LAD) graft is the most important statistical determinant of a favorable outcome after coronary artery bypass grafting (CABG) and can be performed with lower morbidity off pump through a minithoracotomy. PTCA and stenting of the "non-LAD" vessels compete with CABG in terms of patency rates. Our purpose was to compare a combination of minimally invasive direct coronary artery bypass (MIDCAB) and PTCA with double CABG as a treatment for double-vessel coronary artery disease involving the proximal LAD.

METHODS

Two matched groups of 20 patients with double-vessel coronary disease undergoing either sequential MIDCAB and PTCA (group 1) or double CABG on cardiopulmonary bypass (group 2) were compared. Angiographic control, complications, hospital costs, quality of life, and 2-year follow-up of ischemia are reported.

RESULTS

All bypasses were patent at early control. Three adverse events were noted in group 1 and 17 in group 2. The hybrid-procedure group exhibited a shorter intensive care unit stay, fewer blood products transfused, less pain, better early quality of life, faster return to work, and similar cost. Three patients required a second PTCA in group 1, one of which for restenosis. At 2 years all the patients are asymptomatic with no residual ischemia.

CONCLUSIONS

We conclude from this pilot study that the hybrid procedure is feasible and appears to be a safe therapy for double-vessel coronary artery disease and that it appears to generate less perioperative morbidity than classic double CABG does. Therefore we believe that there is room to undertake prospective randomized studies on a larger-scale basis.

Off-pump coronary artery bypass grafting decreases risk-adjusted mortality and morbidity

BACKGROUND

The purpose of this study was to determine whether coronary artery bypass grafting without cardiopulmonary bypass (off-pump CABG) decreases risk-adjusted operative death and major complications after coronary artery bypass grafting in selected patients.

METHODS

Using The Society of Thoracic Surgeons (STS) National Adult Cardiac Surgery Database, procedural outcomes were compared for conventional and off-pump CABG procedures from January 1, 1998, through December 31, 1999. Mortality and major complications were examined, both as unadjusted rates and after adjusting for known base line patient risk factors.

RESULTS

A total of 126 experienced centers performed 118,140 total CABG procedures. The number of off-pump CABG cases was 11,717 cases (9.9% of total cases). The use of an off-pump procedure was associated with a decrease in risk-adjusted operative mortality from 2.9% with conventional CABG to 2.3% in the off-pump group (p < 0.001). The use of an off-pump procedure decreased the risk-adjusted major complication rate from 14.15% with conventional CABG to 10.62% in the off-pump group (p < 0.0001). Patients receiving off-pump procedures were less likely to die (adjusted odds ratio 0.81, 95% CI 0.70 to 0.91) and less likely to have major complications (adjusted odds ratio 0.77, 95% CI 0.72 to 0.82).

CONCLUSIONS

Off-pump CABG is associated with decreased mortality and morbidity after coronary artery bypass grafting. Off-pump CABG may prove superior to conventional CABG in appropriately selected patients.

Clinical outcomes, angiographic patency, and resource utilization in 200 consecutive off-pump coronary bypass patients

BACKGROUND

This retrospective study compared clinical outcomes and resource utilization in patients having off-pump coronary artery bypass grafting (OPCAB) versus conventional coronary artery bypass grafting (CABG). Angiographic patency was documented in the OPCAB group.

METHODS

From April 1997 through November 1999, OPCAB was performed in 200 consecutive patients, and the results were compared with those in a contemporaneous matched control group of 1,000 patients undergoing CABG. Patients were matched according to age, sex, preexisting disease (renal failure, diabetes, pulmonary disease, stroke, hypertension, peripheral vascular disease, previous myocardial infarction, and primary or redo status. Follow-up in the OPCAB patients was 93% and averaged 13.4 months.

RESULTS

Hospital death (1.0%), postoperative stroke (1.5%), myocardial infarction (1.0%), and re-entry for bleeding (1.5%) occurred infrequently in the OPCAB group. There were reductions in the rates of transfusion (33.0% versus 70.0%; p < 0.001) and deep sternal wound infection (0% versus 2.2%; p = 0.067) in the OPCAB group compared with the CABG group. Angiographic assessment of 421 grafted arteries was performed in 167 OPCAB patients (83.5%) prior to hospital discharge. All but five were patent (98.8%) (93.3% FitzGibbon A, 5.5% FitzGibbon B, 1.2% FitzGibbon O). All 163 internal mammary artery grafts were patent. Off-pump coronary artery bypass grafting reduced postoperative hospital stay from 5.7 +/- 5.3 days in the CABG group to 3.9 +/- 2.6 days (p < 0.001), with a decrease in hospital cost of 15.0% (p < 0.001).

CONCLUSIONS

Off-pump coronary artery bypass grafting reduces hospital cost, postoperative length of stay, and morbidity compared with CABG on cardiopulmonary bypass. Off-pump coronary bypass grafting is safe, cost effective, and associated with excellent graft patency and clinical outcomes.

Successful reconstruction of stripped superficial femoral vein

A 69-year-old man who had hemorrhagic shock after inadvertent stripping of the right superficial femoral-popliteal vein during surgery for greater saphenous vein varicosis in another hospital was referred to us. Phlebography revealed a ruptured popliteal vein with intact profunda femoris and common femoral veins. The stripped superficial femoral-popliteal vein brought in a jar was reimplanted. Phlebography performed during the patient's follow-up visits in our outpatient clinic 11 months postoperatively showed a patent femoral vein.

One-year clinical outcome after minimally invasive direct coronary artery bypass

BACKGROUND

Minimally invasive coronary artery bypass (MIDCAB) is a new surgical technique by which the left internal mammary artery is anastomosed under direct visualization to the left anterior descending artery without cardiopulmonary bypass.

METHODS AND RESULTS

We followed all 274 patients who underwent MIDCAB from the time it was introduced at a single center. In-hospital and 1-year clinical events were source-documented and adjudicated. The in-hospital major acute cardiac event rate was 2.2%; this included a 1.1% mortality rate. At 1 year, the respective rates were 7.8% and 2. 5%. When compared with the initial 100 procedures, the subsequent 174 procedures had shorter vessel occlusion times (10+/-5 versus 14+/-6 minutes; P:=0.009), times to extubation (6+/-3 versus 14+/-10 hours; P:<0.001), and lengths of hospital stay (2.1+/-1.9 versus 3. 2+/-3.1 days; P:=0.04). Cumulative 1-year adverse cardiac events were 11% in the initial 100 cases and 6% in the subsequent 174 cases (P:=0.17).

CONCLUSIONS

Excellent clinical results can be achieved with the MIDCAB technique. The clinical adverse event rate may decrease with accumulated experience.

Revascularization interventions for ischemic heart disease

Coronary artery bypass grafting and percutaneous transluminal coronary angioplasty are now well established methods of myocardial revascularization. The choice of a method of revascularization depends on several clinical and angiographic parameters. Patients who derive the greatest benefit from coronary artery bypass grafting are those with left main coronary artery disease or those with three-vessel disease with left ventricular impairment. Patients with single-vessel disease achieve more symptomatic relief with coronary angioplasty than with medical therapy alone, but with no improvement in long-term mortality. In nondiabetic patients with multiple-vessel disease, angioplasty and bypass grafting likely yield similar results, and the choice of revascularization technique rests on weighing the more invasive nature of bypass grafting against the need for additional future revascularizations with angioplasty. Diabetic patients with multiple-vessel disease seem to achieve better outcomes with bypass grafting. Minimally invasive bypass surgery is an evolving technique. It is less invasive in nature but its applications are limited, and its advantages over traditional bypass grafting have not yet been shown. Stenting now plays a major role in percutaneous revascularization and is performed in more than two thirds of all interventional procedures. It improves both the short-term and the long-term outcomes of coronary angioplasty. Other novel percutaneous techniques such as directional or rotational atherectomy, laser angioplasty, or thrombectomy devices have not shown convincing superiority over coronary angioplasty alone. Transmyocardial laser revascularization can be performed surgically or percutaneously and may be beneficial in patients with angina refractory to traditional revascularization procedures.

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.

A xiphoid approach for minimally invasive coronary artery bypass surgery

BACKGROUND

The premise for adopting minimally invasive cardiac surgery techniques for myocardial revascularization is to reduce the patient's morbidity without compromising the efficacy of conventional coronary artery bypass. However, opening the pleura has been a limitation of using these approaches.

AIM

We used the xiphoid approach as an alternative to opening the pleura and to minimize pain after minimally invasive coronary artery bypass surgery.

METHODS

We review our surgical experience in 55 patients who underwent minimally invasive direct coronary artery bypass (MIDCAB) surgery through a xiphoid approach between October 1997 and August 1999. Thoracoscopy (n = 31) or direct vision (n = 24) were used for internal mammary artery (IMA) harvesting. Mean patient age was 67 +/- 10 years and 65% were men. The mean Parsonnet score was 23 +/- 10. Performed anastomoses included left IMA (LIMA) to the left anterior descending (LAD) artery (n = 53), LIMA-to-LAD and saphenous vein graft from the LIMA to the right coronary artery (n = 1), and LIMA-to-LAD and right IMA (RIMA) to right coronary artery (n = 1).

RESULTS

Postoperative complications included atrial fibrillation (12%), acute noninfectious pericarditis (12%), and acute renal failure (5%). Mean postoperative length of stay was 4 +/- 2 days. Angiography was performed in 16 patients and demonstrated excellent patency of the anastomoses. There was no operative mortality. Actuarial survival was 98% in a mean follow-up period of 11 +/- 5 months.

CONCLUSIONS

Minimally invasive coronary artery bypass can be performed safely through a xiphoid approach with low morbidity, mortality, and a relatively short hospital stay.

Early outcome and graft patency in mammary artery grafting of left anterior descending artery with sternotomy or anterior minithoracotomy

BACKGROUND

The main objective of this study was to retrospectively compare early outcome and graft patency in patients who underwent coronary artery bypass grafting with the internal thoracic artery to the left anterior descending artery via an anterior minithoracotomy or median sternotomy and without the use of extracorporeal circulation.

METHODS

One hundred thirty consecutive patients were studied. Median sternotomy was performed in 77 patients and anterior minithoracotomy in 53 patients.

RESULTS

There were no differences in early clinical data or persistent postoperative pain between the groups. Early graft patency was 88% in the thoracotomy group and 96% in the sternotomy group (p = 0.3). Five of 7 patients who presented with a significant stenosis at the first coronary angiography had a normal angiogram at the reangiography. None of the patients with nonsignificant stenosis at the early coronary angiography had any clinical signs of ischemia or chest pain.

CONCLUSIONS

In our experience, anterior minithoracotomy and median sternotomy are different and distinguishable regarding early outcome and early graft patency. Most of the stenoses visualized at the early coronary angiography had vanished at a later coronary angiography, which makes the interpretation of the angiogram hazardous as a tool for the decision for redo procedure in the early postoperative period.

Micropumps to support the heart during CABG

OBJECTIVE

To show the effect of myocardial support by micropumps during beating heart CABG for triple vessel disease.

METHODS

In 12 sheep, three coronary arteries (LAD, intermediate branch and circumflex) were consecutively occluded for 10 min. The animals were divided in two groups: group 1 without support (n=6) and group 2 with biventricular support of intravascular micropumps. The pumps (diameter 6.4 mm) were placed through peripheral access (femoral artery and jugular vein) and advanced under fluoroscopic guidance. The hemodynamic evolution was analyzed during the procedure and 2 h of reperfusion. Myocardial flow was assessed by colored microspheres. Differences between groups were analyzed by ANOVA for repeated measurements and post-hoc testing in case of significance.

RESULTS

All of the pump-supported animals survived the procedure, 1 of the control animals died of resistant ventricular fibrillation. At the end of the reperfusion period, the hemodynamic performance and myocardial contractility was significantly better in the pump-supported group (cardiac output: 2.4+/-0.9 vs. 3.3+/-0.9 l/min, P=0.0192; mean arterial blood pressure: 51+/-23 vs. 73+/-9 mmHg, P=0. 036; first derivative of the left ventricular pressure: 561+/-271 vs. 947+/-316 mmHg/s, P=0.0074). After the procedure, subendocardial blood flow was significantly better in all areas of the left ventricle in group 2 (0.935+/-0.427 ml/min per g vs. 0.409+/-0.183 ml/min per g in group 1; P=0.0366).

CONCLUSION

The supported heart is more resistant to repetitive local ischemia. Support by microaxial pumps can make beating heart surgery safer and applicable for more complex cases.

Difficulties in the interpretation of coronary angiogram early after coronary artery bypass surgery on the beating heart

OBJECTIVE

The major objective of this study was to evaluate the findings in early postoperative coronary angiography in patients who underwent coronary revascularization on the beating heart without cardiopulmonary bypass.

METHODS

Eighty-four consecutive patients receiving 113 grafts were studied. A coronary angiography was performed 0 to 5 days postoperatively. All the grafts were reviewed and classified in the following way: grade A (unimpaired run-off); grade B1 (<50 stenosis); grade B2 (>50% stenosis); grade O (occlusion). A second coronary angiography was performed in patients with a stenosis grade B2, 4 to 30 months postoperatively. An exercise test was performed by patients with B1 stenosis.

RESULTS

Overall graft patency was 96% in the 113 grafts. None of the 14 patients with B1 stenosis in the early coronary angiography had any clinical signs of ischemia. Eight of the 12 patients who exhibited B2 stenosis either at the anastomotic site, in the graft or in the distal coronary artery at the first coronary angiography had a normal angiogram at the re-angiography.

CONCLUSION

A majority of stenoses visualized at the early coronary angiography could not be seen at a later coronary angiography, which makes the interpretation of the angiogram unreliable as a tool for the decision as to redo-procedure in the early postoperative period.

Left internal mammary artery grafting to left anterior descending coronary artery by minimally invasive direct coronary artery bypass approach

New surgical techniques for the treatment of the isolated lesion of the left anterior descending coronary artery (LAD) include off-pump surgery, minimal access to the heart, and endoscopic or computer enhanced coronary artery bypass surgery. The term minimally invasive direct coronary artery bypass surgery (MIDCAB) is related to a left-side minithoracotomy, the harvest of the left internal mammary artery (IMA) under direct vision, and an anastomosis performed between IMA and LAD under direct vision, using the technique of mechanical local immobilization by a special device. Alternative techniques include endoscopic harvesting of the IMA, or as a new and still experimental approach, the closed-chest total endoscopic coronary artery bypass grafting (TECAB) with the use of a high tech telemanipulator system. The currently reported results demonstrate the safety of MIDCAB surgery (30-day mortality < 0.5%, perioperative myocardial infarction < 2%, early patency rate between 95% and 98%). Mid-term results after 6 months have shown a patency rate between 94% and 97%, and more than 90% of the patients are without any angina symptoms. Due to this promising results MIDCAB is an alternative treatment for high-grade LAD lesions.