Direct Coronary Artery Bypass Procedure Research Articles

Short-Term Clinical Results of Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) Procedure.

Objectives: Minimally invasive direct coronary artery bypass (MIDCAB) is an alternative for revascularisation of the isolated left anterior descending (LAD) artery or as a multi-vessel (MV) procedure for the diagonal branch (RD) or the left circumflex coronary artery (LCX) region. Methods: From 2021 to 2022, 91 patients underwent MIDCAB or multi-vessel MIDCAB procedures in our heart center. The left internal mammary artery (LIMA) was anastomosed to the left anterior descending artery via the left minithoracotomy approach in all patients. Results: Of the patients, a total of 86.8% were male. Eighty percent of the patients had two- or three-vessel coronary artery disease. The mean age was 65.1 ± 10.1 years. The mean operation time was 2.6 ± 0.8 h. The 30-day mortality was 0. The mean required packed red blood cells (pRBC) was 0.4 ± 1.2 unit. The mean intensive care unit stay (ICU) was 1.5 ± 1.6 days. The mean follow-up time was 1.5 ± 0.5 years. One patient received percutaneous coronary intervention due to de novo stenosis of the RCA. Late mortality was 2.2%. The Kaplan-Meier survival rate was 98.8% at 1 and 2 years. Conclusions: The postoperative complication rate of our MIDCAB cohort is low, and the short-term survival is favorable. Our postoperative and short-term clinical results demonstrate that this procedure is safe and feasible.

Five-Year Survival of Patients Treated with Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) Compared with the General Swiss Population.

To evaluate the midterm follow-up and 5-year survival outcome of the minimally invasive direct coronary artery bypass (MIDCAB) procedure compared with the survival of the general Swiss population. Retrospective study on preoperative data, intraoperative data, and postoperative outcome of patients who underwent MIDCAB surgery between June 2010 and February 2019. To assess validity of this surgical therapy, outcomes were compared with survival data of a gender- and age-matched cohort of the general Swiss population taken from the database of the Swiss Federal Statistical Office. A total of 88 patients were included. Median (interquartile range [IQR[) age was 66 (56-75) years, and 27% (n = 24) were female. The median (IQR) length of the in-hospital stay was 7 (6-8) days. No postoperative stroke occurred. The 30-day mortality was 1.1% (n = 1). Reintervention for failed left internal mammary artery was needed in 1.1% (n = 1). The median (IQR) ejection fraction was 58% (47-60) preoperatively and remained stable during follow-up. The median (IQR) follow-up period was 3 (1.1-5.2) years. Five years postoperatively, 83% (confidence interval, 69-91) of the patients were alive, showing an overlap with the range of survival of the matched subcohort of the general Swiss population (range, 84-100%). Though suffering from coronary heart disease, patients after MIDCAB show almost equal survival rates as an equivalent subcohort corresponding to the general Swiss population matched on age and gender. Thus, our data show this treatment to be safe and beneficial.

Postoperative results of minimally invasive direct coronary artery bypass procedure in 234 patients.

Minimally invasive approach in cardiac surgery has gained popularity. In order to reduce surgical trauma in coronary surgery minimally invasive direct coronary artery bypass (MIDCAB) has already been established. This technique has been introduced for revascularisation of isolated left anterior descending (LAD). It can also be performed for hybrid revascularisation procedure in multi-vessel disease. From 2017 to 2021, 234 patients received MIDCAB operation in our heartcenter 73% were male. Most of the patients had two or three vessel disease (74%). The average age of the patients was 66 ± 12 years mean. The left internal mammary artery (LIMA) was anastomosed to the LAD through left minithoracotomy approach. Multi-vessel MIDCAB (MV-MIDCAB) including two anastomoses (T-graft to LIMA with additional saphenous vein graft) was done in 15% (n = 35). The average operation time was 2.3 ± 0.8 h mean. The 30-day mortality was 1.7% (n = 4). The average amount of packed red blood cells (pRBC) that was given intra- and postoperatively was 0.4 ± 0.8 units mean. The mean intensive care unit stay (ICU) was 1 ± 1.2 days. Three patients (1.3%) had wound infection postoperatively. The rate of neurologic complications was 0.4% (n = 1). Two patients (0.9%) had myocardial infarction and received coronary re-angiography perioperatively including stent implantation of the right coronary artery. The MIDCAB procedure is a safe and less traumatic procedure for selected patients with proximal LAD lesions. It is also an option for hybrid procedure in multi-vessel disease. The ICU stay and application of pRBC's are low. Our MIDCAB results show a good postoperative clinical outcome. However, follow-up data are necessary to evaluate long-term outcome.

Left Internal Mammary Artery to Left Anterior Descending Artery. An Alternative for old, High-Risk, Multivessel, Coronary Artery Disease Patients and an Approach for Hybrid Revascularization

In 1997, the first ambulatory off-pump left internal mammary artery (LIMA) to left anterior descending artery (LAD) anastomosis was performed via xiphoid approach, an intervention known today as the MINI-OPCAB operation. This operation has been performed in more than 150 patients around the world for the management of single and multiple vessel coronary artery disease, and 70 of those cases underwent the procedure in our Foundation from 1997 to 2021, showing no operative mortality or reintervention rates, low conversion rates, early hospital discharge, and 100% graft patency at the follow-ups. The minimally invasive direct coronary artery bypass (MIDCAB) procedure was introduced in 1994 by Benetti from Argentina, and was developed based on our previous experience performing off-pump coronary surgery by manipulating the ascending aorta through a left-sided small thoracotomy. Although it represents one of the most common minimally invasive procedures done worldwide, the original technique is not easy to reproduce, and in most cases the pleura is opened, which increases patients pain, morbidity, hospital length of stay, and hinders the realization of immediate hybrid revascularization after the procedure. The latest minimally invasive approaches for CABG include robotic-assisted procedures, in which the IMAs are harvested using robotic technology or the whole procedure is done using robotic technology. This approach has shown adequate short-term clinical results, however, there are no studies available reporting the procedure’s long-term results. Conclusion: The MINI-OPCAB operation is a friendly approach to perform Minimally Invasive Coronary Bypass Surgery in old, high-risk, multivessel coronary artery disease patients, and it represents a good intervention alternative for the majority of cardiac surgeons and cardiac specialized centers. We also consider this approach as ideal for patients who further require Hybrid Revascularization; however, more experience is needed to validate this initials results.

Effect of pre-operative octenidine nasal ointment and showering on surgical site infections in patients undergoing cardiac surgery

To evaluate the effect of pre-operative octenidine (OCT) decolonization on surgical site infection (SSI) rates. Before-and-after cohort study. Patients undergoing an elective isolated coronary artery bypass graft (CABG) procedure: control group (1st January to 31st December 2013), N=475; intervention group (1st January to 31st December 2014), N=428. The intervention consisted of nasal application of OCT ointment three times daily, beginning on the day before surgery, and showering the night before and on the day of surgery with OCT soap. A median sternotomy was performed in 805 (89.1%) patients and a minimally invasive direct coronary artery bypass procedure was performed in 98 (10.9%) patients. Overall, there was no difference in SSI rates between the control and intervention groups (15.4% vs 13.3%, P=0.39). The rate of harvest site SSIs was significantly lower in patients in the intervention group (2.5% vs 0.5%, P=0.01). Patients who had undergone a median sternotomy in the intervention group had a significantly lower rate of organ/space sternal SSIs (1.9% vs 0.3%, P=0.04). However, there was a trend towards an increased rate of deep incisional sternal SSIs (1.2% vs 2.9%, P=0.08). Multi-variate analysis did not identify a significantprotective effect of the intervention (odds ratio 0.79, 95% confidence interval 0.53-1.15, P=0.27). Pre-operative decolonization with OCT did not reduce overall SSI rates in patients undergoing an elective isolated CABG procedure, but significantly decreased harvest site and organ/space sternal SSIs. Randomized controlled trials, including controlled patient adherence to the intervention, are required to confirm these observations and to determine the clinical utility of OCT in pre-operative decolonization.

Pain and the Quality of Life Following Robotic Assisted Minimally Invasive Surgery.

Minimally invasive bypass grafting is a promising surgical treatment in proximal LAD stenosis procedures. The main goal of this study was to make comparisons between robotically assisted minimally invasive coronary bypass surgery and conventional surgery in isolated proximal LAD lesions in terms of pain and quality of life improvement. The study contains patients with proximal LAD lesions who were treated with robotically assisted minimally invasive coronary artery bypass surgery and conventional bypass surgery between June 2005 and November 2012. Fifty patients treated with coronary bypass with cardiopulmonary bypass and complete sternotomy were categorized as Group 1. Fifty patients who applied for robotically assisted minimally invasive bypass surgery were categorized as Group 2. The evaluations of pain and quality of life were done according to the Verbal Rating Scale (VRS) and SF-36 health survey questionnaire, respectively. The conventional bypass group and robotic group had 4.8 ± 1.9 years and 4.3 ± 1.6 years mean follow-up time, respectively. The robotic bypass group had a significantly shorter ICU stay and hospital stay than the conventional bypass group (P < .05). The pain score was higher in the robotic bypass group on the 1st postoperative day (P < .05), but the score on the 4th postoperative day was higher in the conventional bypass group (P < .05). In terms of domains of the SF-36 questionnaire, patient scores were significantly higher in patients who were operated with robotically assisted minimally invasive direct coronary artery bypass (MIDCAB) procedure than in patients who were operated with conventional bypass technique. Patients operated with robotically assisted MIDCAB procedure had results with lesser pain, shorter ICU stay, and shorter hospital stay than the other group in isolated proximal LAD stenosis. The same group also had better quality of life results according to the SF-36 questionnaire results.

Minimally invasive direct coronary artery bypass surgery with right gastroepiploic artery for redo patients.

Coronary artery bypass grafting (CABG) has been widely performed for coronary artery disease. Therefore, cases requiring reoperative CABG are increasing. We performed a minimally invasive direct coronary artery bypass (MIDCAB) procedure on four patients, as reoperative CABG surgery for the right coronary artery (RCA), employing the right gastroepiploic artery (RGEA). The target sites were the distal RCA in two patients and the posterior descending (PD) branch in the other two. Complete revascularization was accomplished in all patients without sternotomy, cardiopulmonary bypass (CPB), or blood transfusion. The mean operative time was 3.0 h (range: 2.4-3.7 h). Postoperative coronary angiography showed all grafts to be patent. All patients were discharged without postoperative complications and remained free from cardiac events during a mean follow-up period of 1.5 years (range: 0.5-3.0 years). MIDCAB for the RCA, employing the RGEA via a subxiphoid incision showed, excellent revascularization in redo CABG cases. This technique is a safe and effective method for redo cases.

Pro: Robotic Surgery Is the Preferred Technique for Coronary Artery Bypass Graft (CABG) Surgery

OBOTICALLY ASSISTED totally endoscopic coronary artery bypass (TECAB) surgery represents the most advanced procedural development in the field of minimally invasive coronary artery surgery. TECAB surgery is an innovative surgical procedure that utilizes robotic technology to perform the entire coronary revascularization endoscopically in the closed chest. Robotic coronary artery surgery encompasses utilization of robotic assistance in varying degrees from robotically-assisted minimally invasive direct coronary artery bypass (MIDCAB) procedures to TECAB. MIDCAB procedures involve harvesting of the internal mammary artery (IMA) robotically with the coronary anastomoses being performed through a small minithoracotomy under direct visualization. In TECAB procedures, IMA harvesting as well as the coronary anastomoses are performed in a closed chest with robotic assistance through small ports, making this procedure truly minimally invasive.

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

IntroductionMinimally 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.AimWe in this study discuss our surgical experience in the MIDCAB procedure.Material and methodsThirteen 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.ResultsMean 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.ConclusionsMinimally 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.

Combined Transapical Aortic Valve Replacement and Minimally Invasive Direct Coronary Bypass Grafting�A New Concept for Selected High-Risk Patients

Transcatheter aortic valve implantation and minimally invasive direct coronary artery bypass (MIDCAB) procedures are both off-pump treatment options for a subset of higher-risk patients. We present a new, minimally invasive surgical concept involving combining the procedures and performing them through the same thoracic access in a patient with a vascular disorder. We report on a 78-year-old patient with symptomatic calcified aortic stenosis and a critical lesion of the left anterior descending coronary artery. In addition, Rendu-Osler-Weber disease was diagnosed. He was successfully treated with combined off-pump transapical, transcatheter aortic valve implantation and MIDCAB grafting. The initial postoperative recovery was good; however, the patient died 3 months postoperatively from septic complications. This combined procedure performed through the same anterolateral incision was technically feasible and may be a promising, minimally invasive approach for selected patients.

Cumulative sum failure analysis for eight surgeons performing minimally invasive direct coronary artery bypass

Analysis of average and individual surgical performance for minimally invasive direct coronary artery bypass was used to enhance quality control for that operation. A total of 1441 standard minimally invasive direct coronary artery bypass procedures performed from August 1996 to January 2006 were analyzed for mortality and 10 other major perioperative complications. Learning curves and assessment of perioperative outcome were calculated using descriptive statistics and cumulative sum observed minus expected failure analysis for 8 involved surgeons with a personal experience ranging from 27 to 443 procedures. The incidence of in-hospital mortality was 0.9% and compared favorably with the predicted mortality calculated by the logistic EuroSCORE (3.6%, P < .01). Cumulative sum analysis revealed that 2 surgeons crossed the 95% reassurance boundary after 50 operations and that 2 surgeons crossed the 95% reassurance boundary after 100 operations. There were significant differences between surgeons with regard to the learning curves and perioperative complications (3.6%-29.6%, P < .01). Two surgeons crossed the 95% alarm-line indicating unacceptably high failure rates. Minimally invasive direct coronary artery bypass has become a procedure with low mortality and low complication rates, but results are case-load and surgeon dependent. Cumulative sum analysis is a valuable method allowing for a breakdown of complication rates over time displaying individual surgeons' strengths.

Should axillary artery to coronary artery bypass be part of the cardiac surgeon's armamentarium?☆

The axillary artery has been used as an alternate inflow source for revascularization of the lower extremities for four decades. Since 1997, there have been several reports of axillary artery to coronary artery bypass. All cases of axillary artery to coronary artery bypass at our institution from 1997 through 2003 were reviewed. PubMed was queried for publications on this subject and all pertinent reports were reviewed. Thirty-eight patients underwent axillary artery to coronary artery bypass at our hospital. Most (34) of the operations were performed without cardiopulmonary bypass. Saphenous vein (37) or radial artery (1) grafts were placed to one or more coronary arteries from either the left (36) or right (2) axillary artery. Twenty patients underwent sternotomy, and 18 had either a left (16) or right (2) minimally invasive direct coronary artery bypass (MIDCAB) procedure performed. Most of the sternotomies were for primary myocardial revascularization and most of the MIDCABs were reoperations. There were three deaths-all from non-cardiac causes, one myocardial infarction, and one transient brachial plexus injury. Doppler ultrasound, angiographic, and clinical follow-up were limited, but graft patency has been demonstrated up to 9 years. Axillary artery to coronary artery bypass should be part of the armamentarium of surgeons who perform myocardial revascularization operations.

Using the Bonfils Intubation Fiberscope with a Double-lumen Tracheal Tube

Several surgical procedures require single-lung ventilation. Because a double-lumen tube (DLT) allows for independent ventilation therapy (e.g. , continuous positive airway pressure), suctioning, and bronchoscopy of each lung, the DLT is the accepted standard for the treatment of patients undergoing thoracic surgery.1A difficult intubation in this subset of patients is particularly challenging because tube insertion is impeded by the special shape of the DLT and the two separate cuffs, which can be damaged by the patient’s teeth and during repeated insertion maneuvers using intubation tools with sharp surfaces.Recently, in two patients scheduled to undergo a minimally invasive direct coronary artery bypass procedure requiring DLT insertion, direct laryngoscopy failed. Because at our institution the Bonfils intubation fiberscope (Karl Storz GmbH, Tuttlingen, Germany), a rigid fiberscope with a curved tip, is routinely used for managing unexpected as well as anticipated difficult airways,2,3we decided to use the device to aid in DLT placement. The Bonfils intubation fiberscope has a length of approximately 40 cm and an OD of 5 mm. According to the manufacturer, tracheal tubes with an ID of 5.5 mm or greater and a length of 39 cm or less may be used. The length of the DLTs (including tube connector) used in our cases is approximately 42 cm, and the largest ID of the bronchial lumen is approximately 5.1 mm (37 French) and 5.3 mm (39 French), respectively. Usually, the tube is too long for insertion of a Bonfils intubation fiberscope. After shortening both the tracheal and the bronchial connectors to a complete length of 38.5 cm and after ensuring adequate lubrication of the scope with silicone spray, however, the tube’s bronchial lumen was mounted on the scope easily (fig. 1). Shortening of the proximal connectors did not prevent connecting them to the endotracheal tube adapter and subsequently to the right angle adapter attached to the breathing circuit.Using the Bonfils intubation fiberscope, the patient’s mouth is opened, and the scope inserted from the right side of the mouth along the molars after the patient’s head is adjusted in a neutral position. With the insertion of the device, the anesthesiologist performs a jaw-thrust maneuver with his or her left hand to enhance the retropharyngeal space. After this, guided by the right hand, the Bonfils intubation fiberscope is advanced in the glottic aperture. The tube is then released from the scope with the left hand (or by an assistant) and inserted into the trachea under direct visualization. Sometimes, performing simultaneous laryngoscopy with a conventional Macintosh blade by a second anesthesiologist may be helpful to lift up a large tongue impeding advancement of the fiberscope. Finally, the correct position of the tube must be verified with a fiberoptic bronchoscope, because the rigid Bonfils intubation fiberscope should not be advanced in the trachea.In the two cases denoted, the Bonfils intubation fiberscope was an effective tool for placing a DLT. The time to intubation was clinically acceptable, and no damage occurred with respect to the patient’s teeth or soft tissues. Importantly, the cuffs were intact after placement despite a very desolate set of teeth in one patient. The right-sided insertion approach of the scope along the molars may be advantageous in such cases, because touching the front teeth is avoided, and molars are not as sharp-edged as the anterior and canine teeth.Few intubation tools are suitable for DLT placement. The fiberoptic bronchoscope, which has evolved as an accepted standard for management of the difficult airway,4may not be suitable for oral DLT insertion. The limited ID of the bronchial lumen of the DLT only allows use of a relatively small fiberoptic bronchoscope, and elastic oropharyngeal soft tissues, especially a large tongue, may prevent successful passage through the mouth. In conclusion, the Bonfils intubation fiberscope may be used with DLTs of 37 French or greater after appropriate tube shortening in patients with a difficult airway anatomy.* University Hospital Schleswig-Holstein, Campus Kiel, Germany. bein@anaesthesie.uni-kiel.de

Facilitated MIDCAB Using a Magnetic Coupling Device

A 59-year-old male with chronic occlusion of the left anterior descending coronary artery underwent a minimally invasive direct coronary artery bypass procedure using the second generation of a magnetic anastomotic coupling device. Postoperative angiogram demonstrated excellent patency and flow.

Minimally invasive direct coronary artery bypass in a cardiac transplant recipient with allograft vasculopathy

Coronary bypass operation with cardiopulmonary bypass has provided disappointing results for the treatment of cardiac allograft vasculopathy (CAV). We describe a 61-year-old man who underwent heart transplantation for secondary dilated cardiomyopathy in 1995. Consecutively, CAV developed with clinically silent left anterior descending occlusion. After angiographic diagnosis in 1998 he successfully underwent a minimally invasive direct coronary artery bypass procedure. Annual coronary angiography showed a patent left internal mammary to left anterior descending bypass graft more than 4 years after operation. In select cases, minimally invasive direct coronary artery bypass is a therapeutic option for the treatment of CAV.

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.

Comparative economic analyses of minimally invasive direct coronary artery bypass surgery

Objective: This study was undertaken to assess the degree to which published cost comparisons of minimally invasive direct coronary artery bypass through a thoracotomy versus conventional coronary artery bypass grafting, off-pump bypass surgery through a sternotomy, or angioplasty with or without stenting adhered to existing guidelines for performing economic analyses. Methods: We used minimally invasive direct coronary artery bypass (MIDCAB), off-pump bypass surgery, cost-effectiveness, economic analysis, and related keywords to search MEDLINE, other literature databases and article reference lists for English-language economic analyses of minimally invasive direct coronary artery bypass procedures versus other procedures that were published from 1990 to February 2002. We critically appraised article adherence to a 10-item methodologic checklist modified to address issues particularly relevant to minimally invasive direct coronary artery bypass evaluations. Assessment discordance was reconciled by consensus. Results: Ten articles published from June 1997 to March 2001 compared costs and (generally) outcomes of minimally invasive direct coronary artery bypass with those of other procedures. All were nonrandomized comparisons, generally of concurrent intrainstitutional clinical series. Stated results generally favored minimally invasive direct coronary artery bypass, angioplasty, or off-pump bypass surgery through a sternotomy relative to conventional coronary artery bypass grafting. Studies adequately addressed an average of only 24% of applicable checklist items (range 0%-67%). Few studies adequately ensured the comparability of treatment groups, clearly performed intent-to-treat analyses, comprehensively and credibly measured costs that were considered, or clearly addressed costs and results of preprocedural angiography or postprocedural imaging. Only 1 study compared success of revascularization between minimally invasive direct coronary artery bypass and competing alternatives. No studies specified the cost-analysis perspective or included costs of physician or physician assistant care. Conclusions: Most published comparative economic analyses of minimally invasive direct coronary artery bypass have failed to adequately address issues crucial to such evaluations. Future studies should more closely follow well-described principles of clinical epidemiology and cost-effectiveness analysis.J Thorac Cardiovasc Surg 2003;125:618-24

Occlusion versus shunting during MIDCAB: effects on left ventricular function and quality of anastomosis

Background. Minimally invasive direct coronary artery bypass is an established clinical procedure for revascularization of the left anterior descending coronary artery. Mechanical stabilization and temporary occlusion is currently used to perform the anastomosis of the internal thoracic artery to the left anterior descending coronary artery. However, critical reduction of cardiac function can occur as a result of temporary ischemia. The purpose of this study was to evaluate whether ischemic sequelae can be avoided by using temporary intraluminal shunts and whether this alters early outcome. Methods. Thirty-five patients underwent minimally invasive direct coronary artery bypass revascularization using a mechanical stabilizer. In group A (n = 20), the anastomotic site was temporarily occluded by tourniquets. In group B (n = 15), temporary intraluminal shunts were inserted into the anastomotic site without any occlusion of the left anterior descending coronary artery. Anastomosis of the internal thoracic artery to the left anterior descending coronary artery was performed in an identical fashion. A Swan-Ganz catheter was inserted, and transesophageal echocardiographic measurements were obtained for analysis of left ventricular (LV) function. Regional wall motion, cardiac index, stroke volume index, systolic and diastolic LV diameters, and fractional area change were measured during four periods: at the start of the operation (baseline), placement of the stabilizer (stabilization), left anterior descending coronary artery occlusion (occlusion) or insertion of temporary intraluminal shunts (shunt), and 30 minutes after reperfusion (reperfusion). Angiograms were obtained 4 to 6 days postoperatively. Results. In group A, LV performance, cardiac index, stroke volume index, and fractional area change decreased during occlusion whereas systolic diameters increased. Almost two myocardial segments per patient developed severe hypokinesia in the perfusion area. These changes disappeared after 30 minutes of reperfusion, with increased LV function. In group B, LV function remained stable whereas hypokinetic wall motion was only detected in 2 patients. Early angiograms revealed 90% of the grafts were patent in group A versus 100% in group B. The need for percutaneous intervention during the first 6 months was 20% in group A versus 6.7% in group B. Conclusions. The use of temporary intraluminal shunts resulted in reduced acute ischemia and revealed wall motion abnormalities and maintained LV function. Furthermore, this technique suggests an improvement of early graft patency and a lower reintervention rate within the first 6 postoperative months. Thus, use of temporary intraluminal shunts appears to be superior to the occlusion technique early after minimally invasive direct coronary artery bypass procedures.

Reoperative coronary artery bypass grafting using a minimally invasive direct coronary artery bypass procedure.

Reoperative coronary artery bypass grafting with cardiopulmonary bypass tends to cause a higher mortality and morbidity than the primary operation. The purpose of this study was to discuss the effectiveness and safety of a minimally invasive coronary artery bypass procedure for patients who had previously undergone coronary artery bypass surgery. We performed redo single coronary artery bypass grafting to the left anterior descending coronary artery in 9 patients and to the right coronary artery in 3 patients using minimally invasive cardiac surgery. The graft to the left anterior descending coronary artery was taken from the left internal thoracic artery in 5 patients, the right gastroepiploic artery in 3 patients, and from the saphenous vein in the other 1 patient. The graft to the right coronary artery was from the right gastroepiploic artery in all 3 patients. All grafts were patent. There was no major postoperative complication and no surgical or hospital death except one late death. In selected patients, we could safely and completely perform coronary artery bypass re-grafting to the left descending coronary artery or right coronary artery using a minimally invasive operation.

Clinical results with left axillary to left anterior descending coronary artery bypass

Background. The minimally invasive direct coronary artery bypass procedure is not feasible if the left internal mammary artery has been used or has inadequate flow. We have applied a modified minimally invasive direct coronary artery bypass procedure, which uses a graft from the left axillary artery to the left anterior descending coronary artery in such situations. Methods. The graft is anastomosed to the left axillary artery adjacent to the clavicle and tunneled underneath the vein, where it enters the thorax through the first interspace and courses to the left anterior descending coronary artery along the mediastinum. Results. Since 1997 we have used this operation in 22 patients with a mean age of 70 years (range, 52 to 83 years). All patients were high-risk candidates because of advanced age (70 ± 7 years), depressed left ventricular function (mean left ventricular ejection fraction, 38% ± 6%), or previous heart operation (20 of 22, 91%). Conduits for the graft were saphenous vein (n = 18) or radial artery (n = 4). Ten patients were extubated in the operating room, and the mean duration of mechanical ventilation was 5.8 ± 6 hours. There was one operative death (1 of 22, 4.5%). The mean length of intensive care unit and hospital stay was 1.5 days (range, 1 to 6 days) and 6 days (range, 2 to 15 days), respectively. At a mean follow-up of 6 months, all discharged patients are alive and functionally improved. None have required surgical or catheter-based revascularization of the left anterior descending coronary artery. Conclusions. The left axillary artery to left anterior descending coronary artery graft should be considered for high-risk patients in whom a minimally invasive direct coronary artery bypass procedure is not possible.