Decalcification of the mitral annulus: surgical experience in 81 patients.

OBJECTIVE: Mitral valve surgery in the presence of extensive calcification of the mitral annulus is a technical challenge and increases perioperative risk. This study reviews our experience with decalcification of the mitral annulus in patients undergoing mitral valve reconstruction or replacement. METHODS: From 1995 to 2003, 81 patients (mean age 64 +/- 13 years, 30 male, 51 female) with extensive calcification of the mitral annulus underwent mitral valve repair (n = 42) or replacement (biological n = 20, mechanical n = 19). The mean follow-up was 24 months. Patients presented with a mean EuroSCORE of 7. Concomitant surgical procedures were performed in 62 %. Patient outcomes were retrospectively assessed. RESULTS: Perioperative survival was 97.5 % (n = 79) and hospital survival was 91.3 % (n = 74). Two-year survival was 88.9 %. Eight patients needed reexploration due to bleeding and five patients required prolonged mechanical ventilation. No perioperative stroke was observed. Freedom from reoperation was 90.2 % (n = 73). Early reoperation for recurrent incompetence was necessary in 3 patients and late reoperation in 5 patients. CONCLUSIONS: Despite the elevated perioperative risk and the high risk of reoperation with this procedure, decalcification of the annulus and repair/replacement of the mitral valve could be performed with good clinical results.

Does totally endoscopic access for off-pump cardiac surgery influence the incidence of postoperative atrial fibrillation in coronary artery bypass grafting? A preliminary report.

BACKGROUND: The occurrence rate of atrial fibrillation (AF) after coronary artery bypass grafting, quoted in the literature, is wide ranging from 5% to over 40%. It is speculated that, off-pump coronary artery bypass grafting (OPCAB) and also minimally invasive cardiac surgery reduces the incidence of postoperative AF due to reduced trauma, ischemia, and inflammation. Current data, however, do not clearly answer the question, whether the incidence of postoperative AF is reduced in using minimally invasive techniques, ideally resulting in the combination of both small access and off-pump surgery. The aim of this study was to evaluate the incidence of postoperative AF in patients undergoing totally endoscopic off-pump coronary artery bypass grafting (TECAB). METHODS: A retrospective analysis of 72 patients undergoing myocardial revascularization was performed. Early postoperative incidence of AF was compared between three groups of patients: 24 after conventional coronary artery bypass grafting (CABG), 24 after OPCAB, and 24 after totally endoscopic off-pump CABG. Clinical profile of the patients, including factors having potential influence on postoperative AF was matched for groups. RESULTS: Postoperative AF occurred in 25% of the patients in the CABG group, in 16% of the patients in the OPCAB group, and in 16% of the patients in the TECAB group. This difference has no statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups excepting the number of distal anastomoses. There was a statistical significance between CABG group and TECAB group. CONCLUSION: Avoiding cardiopulmonary bypass and minimizing surgical trauma did not reduce the incidence of postoperative AF in this patient collective. It remains an attractive hypothesis that postoperative AF is reduced by off-pump myocardial revascularisation and minimizing surgical trauma but more robust data are required.

Moderate hypothermia (30 degrees C) for surgery of acute type A aortic dissection.

OBJECTIVE: Antegrade cerebral perfusion has proved to be a reliable method of brain protection during surgery of thoracic aneurysms. In addition, the drawbacks of deep hypothermia may be avoided. This study examines the outcome after surgery for acute type A aortic dissections (AAD) using moderate (30 degrees C) systemic hypothermia compared with conventional techniques of cerebral protection. METHODS: Between January 1999 and August 2003, 74 patients underwent repair of acute type A aortic dissection. Moderate systemic hypothermia (30 degrees C) with selective antegrade cerebral perfusion through subclavian artery (group A) was used in 18 patients. Deep hypothermia (20 - 24 degrees C) was employed using either retrograde (18 patients, group B) or antegrade (38 patients, group C) cerebral perfusion. Tube graft replacement was performed in 55, valve-sparing procedure in 8, and composite graft replacement in 11 patients. RESULTS: The 30-day mortality was 5.5 % in group A, 5.5 % in group B, and 15.8 % in group C (A vs. C and B vs. C; p < 0.01). New postoperative permanent neurologic deficit occurred in 5.5 % of patients in group A, 16.7 % in group B, and 13.2 % in group C. Mean chest tube drainage within the first 24 h in groups A, B and C was 703 +/- 338, 1178 +/- 820, and 1447 +/- 802 ml, respectively (A vs. B and A vs. C; p < 0.01). Cardiopulmonary bypass, ICU, and hospital times were significantly shorter in group A. CONCLUSIONS: Selective antegrade cerebral perfusion with moderate systemic hypothermia appears to be a safe and sufficient tool for brain protection during AAD repair. In avoiding deep hypothermia, this technique may help to reduce cardiopulmonary bypass time and hypothermia-related side effects.

Segmental myocardial wall motion during minimally invasive coronary artery bypass grafting using open and endoscopic surgical techniques.

Current options for minimally invasive surgical treatment of single-vessel coronary artery disease include beating heart procedures without cardiopulmonary bypass (CPB) via mini-thoracotomy (MIDCAB) and totally endoscopic robot-assisted techniques (TECAB) with CPB. Both procedures are associated with potential myocardial stress before revascularization, such as single-lung ventilation (SLV), temporary coronary artery occlusion, cardiac luxation, intrathoracic carbon dioxide insufflation, and extended CPB and operating time. In this echocardiographic study we sought to evaluate the extent of intraoperative segmental wall motion abnormalities (SWMA) during MIDCAB and TECAB surgery and to identify factors affecting SWMA. Forty-six patients with single-vessel coronary artery disease were studied. Sixteen patients were operated using the MIDCAB technique and 30 patients with TECAB. In both groups sequential transesophageal echocardiograms were recorded during the entire procedure. Hemodynamic data and oxygenation variables were acquired simultaneously. In both groups, mild but obvious perioperative SWMA were identified and noted to increase during the course of the operation. These SWMA were more pronounced in the TECAB group. Independent of operating time, these changes disappeared completely after revascularization. No significant hemodynamic compromise was observed. We conclude that MIDCAB and TECAB techniques are associated with significant perioperative SWMA. The appearance of more profound SWMA in the TECAB group compared with the MIDCAB patients might have been the result of intrathoracic CO(2) insufflation, as SLV was used in both groups. No persistent SWMA or post-CPB SWMA were apparent in either group. More extensive intraoperative ventricular SWMA was detected in the TECAB group, suggesting that a more frequent risk for right ventricular dysfunction may exist during TECAB procedures.

Totally endoscopic coronary artery bypass graft: initial experience with an additional instrument arm and an advanced camera system.

BACKGROUND: Robotically enhanced telemanipulation for totally endoscopic coronary artery bypass does not provide adequate tactile feedback, traction, or countertraction. The exposition of coronary target sites is difficult, the visual field is limited, and the epicardial stabilization may be troublesome. A fourth robotic arm for endothoracic instrumentation has been added to the da Vinci surgical system to facilitate totally endoscopic operations. The stereoendoscope was upgraded with a wide-angle feature. METHODS: The procedure was performed in five patients. Four of these patients had left internal thoracic artery (LITA) to left anterior descending artery (LAD) grafting on the beating heart and the fifth had sequential bypass grafting (LITA to diagonal branch and LAD) on an arrested heart. The additional effector arm of the da Vinci surgical system was brought into the operative field beneath the operating table and used as a second right arm. The wide-angle view was activated by either the console or the patient side surgeon. RESULTS: The mean operative, port placement, and anastomotic times for a beating-heart totally endoscopic coronary artery bypass were 195 +/- 58, 25 +/- 10, and 18 +/- 5 min, respectively. All procedures were free of morbidity and mortality, with satisfactory angiographic control. The sequential arterial bypass grafting procedure was fully completed in totally endoscopic technique. CONCLUSIONS: The additional instrumentation arm and wide-angle visualization are useful technical improvements of the da Vinci surgical system, solving the problem of traction, countertraction, and facilitated exposition of target sites as well as visualization of the surgical field. They provide potential for wider acceptance of totally endoscopic coronary artery bypass grafting in a larger surgical community.

Cardiopulmonary bypass impairs left ventricular function determined by conductance catheter measurement.

OBJECTIVE: Postoperative cardiac depression is attributed to ischemia and the effects of cardiopulmonary bypass (CPB). To evaluate the effect of CPB alone on postoperative left ventricular (LV) dysfunction, we used a conductance catheter to determine the LV performance by pressure-volume relation before and after CPB. METHODS: Twenty-two 3-week-old piglets underwent sternotomy and normothermic CPB for one hour. A conductance catheter was placed in the LV cavity. End-systolic pressure-volume relationships (ESPVR), left ventricular end-diastolic pressure (LVEDP) and systemic vascular resistance (SVR) were measured under steady-state conditions before and 15 min after weaning from CPB in group A (n = 11). Group B included 11 piglets without CPB and served as control. RESULTS: There was no difference between groups before initiating CPB. As an indication of depressed LV function, the ESPVR slope (mmHg/ml) was significantly lower in group A after weaning from CPB than in group B (1.69 +/- 0.5 vs. 1.86 +/- 0.55; p = 0.008). In group A, peak dP/dt (max index) (mmHg/s/m (2)) decreased markedly (1596 +/- 339 vs. 2045 +/- 206; p = 0.03), while LVEDP (mmHg) was significantly increased (11.7 +/- 2.6 vs. 5.4 +/- 0.9; p < 0.0001). In addition, SVR (index) (dyn x s x cm (-5)/m (2)) in group A was significantly lower (1407 +/- 176 vs. 1677 +/- 313; p < 0.0001) than in group B. CONCLUSION: Using the very sensitive conductance catheter technique in a pig model, we could show that CPB leads to a significant depression of LV contractility and elastance even without ischemic arrest.

Perioperative elastase activity in cardiac surgery and its role in endothelial leakage.

OBJECTIVE AND DESIGN: The functional activity and pathophysiological effects of polymorphonuclear elastase (PMNE) in cardiac surgery patients are unknown. This in vitro study was done to evaluate whether PMNE activity in patient blood samples may be correlated with decreased endothelial wall integrity. METHODS AND SUBJECTS: PMNE was serially analyzed by PMNE activity in plasma samples from 40 high risk cardiac surgery patients. Endothelial cell cultures were used to study the influence of patient serum on the intercellular integrity. RESULTS: Ex vivo, samples with high PMNE activity (>1.0 mg/ ml), found in 14 patients (35%), neither induced hyperpermeability in cultured endothelial cells nor resulted in intracellular redistribution of the junction molecules cadherin-5 or beta-catenin. However, pretreatment of endothelial cells with these samples but not with low activity (<0.5 mg/ml) samples augmented neutrophil transendothelial migration (>20-fold) in conjunction with formation of intercellular gaps and irregular membrane-associated beta-catenin staining. Neutrophil transmigration was inhibited by blocking neutrophil beta1 integrin but not by the proteinase inhibitor methoxysuccinyl-Ala-Ala-Pro-Ala. CONCLUSIONS: Augmented PMNE activity in cardiac surgery patients does not directly induce endothelial leakage but may indirectly promote neutrophil extravasation and thus perioperative endothelial hyperpermeability.

Operative techniques in awake coronary artery bypass grafting.

BACKGROUND: Off-pump coronary artery bypass grafting was implemented to reduce trauma of surgical coronary revascularization by avoiding extracorporeal circulation. High thoracic epidural anesthesia further reduces intraoperative stress and postoperative pain. In addition, this technique even allows awake coronary artery bypass grafting, avoiding the drawbacks of mechanical ventilation and general anesthesia in high-risk patients. METHODS: Thirty-four patients underwent awake coronary artery bypass grafting with left internal thoracic artery to left anterior descending coronary artery by partial lower ministernotomy (n = 20), H-graft technique (n = 2), or rib cage-lifting technique (n = 2). In 9 cases we performed double bypass grafting, and in 1 case we performed triple-vessel coronary artery revascularization through complete median sternotomy. In addition to clinical outcomes, visual analog scale pain scores were recorded on days 1, 2, and 3 after surgery. RESULTS: Thirty-one patients remained awake throughout the whole procedure. Three patients required secondary intubation because of incomplete analgesia (n = 1) or pneumothorax (n = 2). Procedure time was 90 +/- 31 minutes, and recovery room stay was 4.2 +/- 0.6 hours. There were no in-hospital deaths or serious postoperative complications. In 1 case a graft occlusion was documented on predischarge angiography. Early postoperative pain was low (visual analog scale score of 30 +/- 6). CONCLUSION: These data demonstrate the feasibility and safety of various surgical coronary revascularization techniques without general anesthesia. Continuation of thoracic epidural analgesia provides good pain control and fast mobilization postoperatively. Surprisingly, the awake coronary artery bypass grafting procedure was well accepted by the patients.

First report on sequential totally endoscopic thymomectomy and adrenalectomy using computer-enhanced telemanipulation.

BACKGROUND: Laparoscopic adrenalectomy is considered the standard method for removal of benign adrenal tumors, regardless of hormone activity. Minimally invasive surgery for thymomectomy aims at limited approaches, avoiding complete sternotomy or large thoracotomy. METHODS: We report on a case in which totally endoscopic thymomectomy and adrenal gland resection were performed sequentially using a computer-enhanced telemanipulation system within 3 weeks. RESULTS: Operating time was 4.5 h for totally endoscopic adrenalectomy and 1.5 h for totally endoscopic thymomectomy. The patient was transferred to the normal ward on the day of operation after either procedure and had an uneventful recovery. Pathology yielded no malignancy in both cases. CONCLUSION: This report demonstrates the safety and feasibility of various totally endoscopic procedures performed sequentially.

Do surface modifying additives (SMA) influence blood loss and thrombogenicity in conventional cardiopulmonary bypass for coronary artery bypass grafting?

Cardiopulmonary bypass (CPB) leads to activation of the coagulation and fibrinolytic cascades, partially associated with foreign surface contact. Hemorrhage and the need for blood products is associated with rising cost and increased risk of infection. Treatment with surface modifying additives (SMA) has been shown to reduce thrombogenicity and improve biocompatibility. 76 elective CABG-patients were randomly assigned to surface modifying additives (group I, n=39) or untreated circuits that were otherwise identical (group II, n=37). Measurements of coagulation activity and fibrinolysis, platelet count and function were made. The postoperative blood loss and blood product replacement was also assessed. Thrombin formation measured by prothrombin fragments 1+2 (5.7+/-0.4 nmol/l vs. 5.6+/-0.4 nmol/l), fibrinolytic activity measured by plasmin-antiplasmin complex (1752.6+/-216.8 microg/l vs.1180.0+/-74.8 microg/l) and the postoperative platelet count and function did not differ significantly between the two groups. Blood loss and transfusion requirements were slightly lower in the SMA group. The treatment of extracorporeal surfaces with surface modifying additives does not appear to reduce coagulation disorders and bleeding after conventional CPB.

Performance of stentless versus stented aortic valve bioprostheses in the elderly patient: a prospective randomized trial.

OBJECTIVES: Although stentless aortic bioprostheses are believed to offer improved outcomes, benefits remain unsubstantiated. The aim of our study was to compare stentless with stented bioprostheses, with regard to postoperative changes in left ventricular mass and hemodynamic performance, in the elderly patient. METHODS: Forty patients with aortic stenoses, over the age of 75 years, were randomized to receive either the stented Perimount (n=20) or the stentless Prima Plus (n=20) bioprosthesis. Left ventricular mass regression, effective orifice area, ejection fraction and mean gradients were evaluated at discharge, 6 months and 1 year after surgery. RESULTS: Overall a significant decrease in left ventricular mass was found 1 year postoperatively. However, there was no significant difference in the rate of left ventricular mass regression between the groups. Furthermore, 1 year postoperatively, the hemodynamic performance of the valves and the change in the ejection fraction did not differ between the groups. CONCLUSIONS: Our study shows that in a randomized cohort of elderly patients with aortic stenosis, we were not able to detect significant differences, with regard to hemodynamic performance and regression of left ventricular mass, between the stentless and stented valve groups. To our surprise, previously reported findings of non-randomized trials that showed faster and more complete regression of left ventricular mass and hemodynamic benefits of stentless valves were not reproducible.

Left ventricular thrombus capture by an intra-aortic filter device.

Left ventricular aneurysmectomy in patients with mobile, protruding thrombi is associated with increased risk of neurological complications due to loss during left ventricular luxation or embolisation of residual thrombotic material after incomplete removal. Embolisation can be prevented by application of an intra-aortic filter device. Here, we report on a case involving an important left ventricular thrombus captured in a patient referred for coronary artery bypass grafting, left ventricular aneurysmectomy, and thrombectomy.

Computer-enhanced telemanipulation enables a variety of totally endoscopic cardiac procedures.

BACKGROUND: Since its introduction in the field of cardiac surgery in 1997, computer-enhanced telemanipulation has been used in a number of different specialized areas. In cardiac surgery, various procedures have been successfully completed in totally endoscopic fashion ever since. Between June 1999 and January 2002, 75 closed-chest cardiac procedures have been performed at our institution using the da Vinci telemanipulation system. PATIENTS AND METHODS: In 42 patients, a single-vessel totally endoscopic coronary artery bypass was performed on the arrested heart (left internal thoracic artery (LITA) to left anterior descending artery (LAD), n = 36; right internal thoracic artery (RITA) to right coronary artery (RCA), n = 6). 12 patients had different types of multivessel revascularization using both internal thoracic arteries. 8 patients underwent LITA-to-LAD grafting on the beating heart. 10 patients underwent closure of an atrial septal defect (9 direct, 1 patch). 3 patients received an epicardial left ventricular pacemaker lead, 2 of which were reoperations. RESULTS: Overall conversion rate to any kind of incision was 25 %. The last 26 LITA to LAD patients on the arrested heart had a conversion rate of 4 %. There were no mortalities, 3 patients required reexploration via a median sternotomy, and one patient suffered a hypoxemic brain damage. The first 22 TECAB patients demonstrated excellent graft patency in angiographic control upon discharge. None of the atrial septal defect (ASD) closures showed any residual shunt on the intraoperative transesophageal echocardiogram (TEE). Patients with end-stage heart failure had successful biventricular stimulation. CONCLUSION: Our current experience confirms the feasibility of various totally endoscopic cardiac procedures with good clinical outcomes. After a steep learning curve, the conversion rate could be lowered to an acceptable figure. Some of these procedures at our institution became a reasonable treatment alternative in selected patients.

Optimal carbon dioxide application for organ protection in cardiac surgery.

BACKGROUND: Cardiac surgery is associated with an important risk of central or peripheral organ damage, attributed in part to air embolism from incompletely deaired cardiac chambers. Insufflation of carbon dioxide into the thoracic cavity is widely used for organ protection in cardiac surgery. METHODS: In patients operated on through a sternotomy, the gas was insufflated through a standard cardioplegia line (group I, n = 10) or a Jackson-Pratt drain (group II, n = 10), with flow rates of 2, 4, and 6 L/min. In patients undergoing mitral valve surgery through a right anterolateral minithoracotomy, application through a gas port (group III, n = 10) was compared with application through a Veress needle (group IV, n = 10). In groups I and IV measurements were repeated with a gauze sponge to divert the gas stream. RESULTS: At a flow of 2 L/min, carbon dioxide levels in the thoracic cavity reached 52% +/- 30% in group I and increased to 81% +/- 27% when a gauze sponge was used. In group II a level of 91% +/- 5% was achieved. In minimally invasive procedures carbon dioxide levels reached 92% +/- 6% in group III and 60% +/- 25% in group IV without a gauze sponge and 97% +/- 2% in group IV with a gauze sponge. Increasing flow rates from 2 to 6 L/min decreased carbon dioxide levels in the thoracic cavity. Arterial blood gas analysis did not reveal critical levels of partial pressure of carbon dioxide at any time. CONCLUSIONS: For optimized carbon dioxide concentrations during cardiac procedures, jet effects in the thoracic cavity have to be avoided. The highest levels were achieved with infusion lines covered by a gauze sponge or a perforated drain for conventional operations and a sponge-covered Veress needle or a gas port for minimally invasive approaches.

[Successful reoperation of a ruptured aortic arch aneurysm in Takayasu arteritis]. / Erfolgreiche Reoperation eines rupturierten Aortenbogenaneurysmas bei Takayasu Arteriitis.

Successful reoperation of a ruptured aortic arch aneurysm in a patient with Takayasu's disease. Takayasu's disease is an inflammatory arteriopathy that often progresses to stenosis or aneurysms of the large arteries of the aortic arch. In this connection aneurysms of the ascending aorta are rare. We report the case of a 33 years old female with a ruptured aneurysm of the ascending aorta complicated by a former operation of a truncobicarotidal bypass and severe sclerosis. After ascending aorta and aortic arch replacement was performed in deep hypothermia circulatory arrest we could discharge the patient in good condition on the 11. postoperative day.

Totally endoscopic coronary artery bypass grafting on cardiopulmonary bypass with robotically enhanced telemanipulation: report of forty-five cases.

BACKGROUND: Robotically enhanced telemanipulation is a new powerful tool for minimally invasive procedures that allows totally endoscopic cardiac surgery. Between June 1999 and February 2001, 45 robotically enhanced totally endoscopic coronary artery bypass grafting procedures on the arrested heart were performed at our institution with the use of the da Vinci telemanipulation system (Intuitive Surgical, Inc, Mountain View, Calif). METHODS: In 37 patients a single-vessel totally endoscopic coronary bypass operation was performed. Eight patients had different types of multivessel revascularization with both internal thoracic arteries. The initial conversion rate was 22% and dropped to 5% in the last 20 patients. Two patients required reexploration via median sternotomy. The first 22 patients had excellent graft patency on discharge. The procedural time for single-vessel totally endoscopic bypass was 4.2 +/- 0.4 hours, bypass time was 136 +/- 11 minutes, and aortic crossclamp time amounted to 61 +/- 5 minutes. CONCLUSION: The present data show the feasibility of closed chest single- and double-vessel revascularization, with good clinical results. However, procedural time is prolonged and the complex endoscopic and endoaortic occlusion techniques, as well as the extensive anesthesiologic monitoring, are demanding. The need for conversion to an open procedure diminished after a relatively short learning curve. All postulated benefits of totally endoscopic surgery other than excellent cosmesis must be evaluated in larger cohorts.

[Total arterial bypass operations with complete sternotomy in the awake patient]. / Totalarterielle Bypassoperationen über komplette Sternotomie am wachen Patienten.

BACKGROUND: In minimally invasive coronary artery bypass surgery beating heart procedures and operations via limited incisions became more popular and are routinely performed in many centers. An additional approach to minimize general trauma is avoidance of general anesthesia endotracheal intubation. PATIENTS AND METHODS: Between March and June 2001, 14 spontaneously breathing patients underwent coronary artery bypass grafting on the beating heart without general anesthesia. Intra- and postoperative analgesia management was performed using continuous epidural infusion of local anesthetics at level Th2-Th3. Single (n = 8) as well as double (n = 5) and triple (n = 1) bypass grafting was performed with the off pump technique. Surgical access to the chest cavity was created via partial (n = 8) or complete sternotomy (n = 6). RESULTS: Twelve patients remained awake throughout the procedure; 2 patients required secondary intubation due to incomplete sensory block and pneumothorax. Operating time was 94 +/- 18 minutes. Intermediate care monitoring time amounted to 4.8 +/- 0.6 hours. No surgery-related complications or myocardial infarction occurred. Postoperative angiography reviewed good graft function in all patients. CONCLUSION: Our preliminary experience shows that complete surgical revascularization is safe and feasible without endotracheal intubation and general anesthesia. Thus, invasiveness in cardiac surgery is further reduced with less need for intensive care unit monitoring enabling faster mobilization and recovery.

Sutured coronary artery grafting utilizing the Heartflo anastomosis device--first clinical experiences.

BACKGROUND: The Heartflo device was developed to facilitate consistency in distal coronary anastomosis quality. The device automates the suturing process during the anastomosis procedure via simultaneous delivery of ten standard 7-0 polypropylene sutures through the graft and the coronary vessel wall. METHODS: In 30 elective coronary artery bypass patients, one distal anastomosis was intentionally performed with the anastomosis device. Device success was stated if a patent anastomosis with a minimal flow of 50 ml/min resulted, additional stitches were counted if bleeding occurred. RESULTS: 4 cases of device failure occurred in the first 5 patients. The subsequent patients were operated without any mechanical problems. In 16 patients (53 %), a patent anastomosis with a mean flow of 75 +/- 6 ml/min using 1.7 +/- 0.3 additional stitches was achieved. Anastomoses were completed in 19.0 +/- 0.7 min; postoperative course was uneventful in all patients. CONCLUSIONS: We have shown that coronary anastomoses are feasible using the Heartflo device, representing a promising step on the way to automated coronary anastomoses. Its application is still limited by the size and tissue quality of the target vessel and difficult suture management during the anastomosis procedure.

Totally endoscopic coronary artery bypass grafting on the arrested heart is a prerequisite for successful totally endoscopic beating heart coronary revascularisation.

Telemanipulators have been introduced into cardiac surgery recently expanding the scope of minimally invasive techniques and enabling endoscopic cardiac surgery. Our aim was to evaluate clinical results of totally endoscopic single vessel bypass grafting on the arrested as well as on the beating heart. Since 1999, 44 totally endoscopic single vessel arterial bypass grafting procedures were performed at our institution. Thirty-eight procedures were performed on the arrested heart (group A), and six such procedures on the beating heart (group B) using the daVinci telemanipulation system. In group A, totally endoscopic coronary artery bypass grafting (TECAB) with left internal thoracic artery (LITA) to left anterior descending artery (LAD) was performed in 33 patients and right internal thoracic artery (RITA) to right coronary artery (RCA) grafting in five cases. The overall conversion rate in group A was 18.4% and dropped down to 5% in the last 20 cases. In group B (n=6), four patients received successful LITA to LAD grafting; two patients (33%) required conversion to minithoracotomy. The first 22 TECAB patients of group A (58%) had control angiography and demonstrated excellent graft patency upon discharge. All grafts in group B showed excellent function on angiographic control as well. The mean procedural time for single vessel TECAB was 4.2+/-0.9h, cardiopulmonary bypass (CPB) time was 136+/-32 min and aortic cross-clamp time amounted to 61+/-16 min. The present data show feasibility of totally endoscopic single arterial grafting on the arrested heart in a reproducible manner, though procedural times were still prolonged due to the difficult handling of the port access system and the complex time consuming endoscopic operation. A low conversion rate was achieved in arrested heart TECAB after a relatively short learning curve and is mandatory for successful totally endoscopic off-pump bypass grafting.

Echocardiographic findings in minimally invasive coronary artery bypass grafting: The role of intrathoracic CO2 - insufflation and single lung ventilation.

BACKGROUND: Current options for surgical treatment of coronary single vessel disease range from beating heart procedure without cardiopulmonary bypass via a mini thoracotomy (MIDCAB) to totally endoscopic robot-assisted techniques (TECAB) with cardiopulmonary bypass. Both procedures are associated with considerable stress even before revascularization such as single lung ventilation, temporary coronary occlusion, Luxatio cordis, intrathoracic CO2 insufflation and extended bypass and operating time. The aim of the this study was to document the extent of intraoperative segmental wall motion abnormalities (SWMA) by echocardiography, and to identify variables affecting SWMA. MATERIALS AND METHODS: Forty patients with coronary single vessel disease were included in the study. 16 patients were operated with the MIDCAB technique, and 24 patients underwent TECAB. In both groups of patients sequential transesophageal echocardiograms (2D-loops) were recorded and analyzed. Hemodynamic and electrocardiographic data as well as oxygenation parameters were acquired during echo exams. In both groups of patients mild, but significant perioperative SWMA were identified, which increased in the course of the operation. These SWMA were more pronounced in the TECAB as compared to the MIDCAB group. Independent of operating time these changes disappeared completely until the ends of surgery. Significant hemodynamic or elektrocardiographic modifications were not observed. CONCLUSION: The application of minimally invasive techniques for the surgical treatment of coronary single vessel disease is associated with significant perioperative SWMA. The more pronounced SWMA in the TECAB group may be a consequence of intrathoracic CO2-insufflation. Both techniques can be applied without significant myocardial ischemia, provided that appropriate intraoperative monitoring is performed, and intrathoracic CO2 pressure in TECAB patients is limited.