Tayfun Aybek

Totally endoscopic atrial septal repair in adults with computer-enhanced telemanipulation

OBJECTIVE Standard surgical closure of an atrial septal defect via sternotomy is a safe and effective procedure with low morbidity and mortality. Considering that young female patients are frequently operated on for atrial septal defects, a minimally invasive procedure avoiding sternotomy is convincingly desirable and led to the approach through a right anterolateral minithoracotomy. The recent clinical introduction of robotically assisted surgery further reduced skin incisions and enabled totally endoscopic procedures through ports. This article reports on a first series of atrial septal defect closures of which the first case was operated on August 24, 1999, in a totally endoscopic closed chest technique using a computer-enhanced telemanipulation system. METHODS We performed totally endoscopic atrial septal repair using the da Vinci surgical system (Intuitive Surgical, Mountain View, Calif) in 10 consecutive adult patients. Median age was 45.5 +/- 10.0 years, and preoperative New York Heart Association functional class was 1.8 +/- 0.1. Left ventricular ejection fraction was normal in all patients and mean pulmonary artery pressure amounted to 35 +/- 7 mm Hg. Shunt volume ranged from 24% to 70%. All patients displayed a fossa ovalis type of atrial septal defect; 2 of them multiperforated. RESULTS Neither intraoperative nor postoperative complications occurred. Two patients had to be converted to minithoracotomy due to endoaortic balloon clamp failure. Length of operation was 262 +/- 37 minutes, and cardiopulmonary bypass time was 161 +/- 26 minutes. Intraoperative transesophageal echocardiography certified complete closure of the atrial septal defect in all patients. The totally endoscopic computer-enhanced technique yielded excellent cosmetic results. CONCLUSION Totally endoscopic atrial septal repair is a feasible and safe procedure with good clinical results and excellent cosmetic outcomes. It may be considered as perfect adjunct to interventional treatment options. Further studies with larger cohorts and randomized trials are necessary to document potential benefits. Evolution in robotic technology and refinement of procedural flow may shorten procedural time and decrease costs.

Antegrade Cerebral Perfusion With Mild Hypothermia for Aortic Arch Replacement: Single-Center Experience in 245 Consecutive Patients

BACKGROUND Aortic arch replacement remains a surgical challenge because of prolonged operative times, bleeding complications, and a considerable risk of neurologic morbidity and mortality. This study investigates our clinical results after modification of perfusion technique for cardiopulmonary bypass as well as temperature management for these high- risk patients. METHODS Between January 2000 and January 2009, 245 consecutive patients underwent aortic arch repair during selective antegrade cerebral perfusion (ACP) with mild systemic hypothermia (30.5°C±1.4°C). Mean age was 63±12 years, 175 patients (71%) were men and 141 patients (58%) had acute type A dissection. Hemiarch replacement was performed in 152 patients (62%) while the remaining 93 patients (38%) underwent total arch replacement. RESULTS Cardiopulmonary bypass time accounted for 168±62 minutes, and myocardial ischemic time was 103±45 minutes. Isolated ACP was performed for 38±27 (range 12 to 135) minutes. Chest tube drainage during the first 24 hours was 563±248 mL. Mean ventilation time was 44±22 hours. Serum lactate levels at 1, 12, and 24 hours postoperatively rose to 19±11, 33±14, and 20±8 mg/dL, respectively. We observed new postoperative permanent neurologic deficits in 14 patients (6%) and transient neurologic deficits in 12 patients (5%). The operative mortality rate was 8% (n=20). Among patients with ACP times 60 minutes or greater (n=28; 92±29 minutes), permanent neurologic deficits occurred in 2 individuals (n=2 of 28; 7%) and operative mortality was 7% (n=2 of 28). At late follow-up (3.8±3.2 years, 98% complete), 196 patients (80%) were still alive. CONCLUSIONS Selective ACP in combination with mild hypothermia offered sufficient cerebral as well as distal organ protection in our patient cohort. Thus, current data suggest that this standardized perfusion and temperature management protocol can safely be applied to complex aortic arch surgery requiring up to 90 minutes of isolated ACP times.

Antegrade Cerebral Perfusion for Acute Type A Aortic Dissection in 120 Consecutive Patients

BACKGROUND Treatment of acute type A aortic dissection remains a surgical challenge because of prolonged operative times, bleeding complications, and a considerable risk of neurologic morbidity and mortality. The following study investigates clinical results after modification of perfusion technique for cardiopulmonary bypass as well as temperature management. METHODS Between January 2000 and August 2006, 120 consecutive patients underwent repair of acute type A dissection. Selective antegrade cerebral perfusion through the right subclavian artery combined with mild systemic hypothermia (30 degrees C) was used in all patients. RESULTS Mean cardiopulmonary bypass time was 144 +/- 53 minutes, and mean myocardial ischemic time was 98 +/- 49 minutes. Isolated cerebral perfusion was performed for 25 +/- 12 minutes. Mean core temperature amounted to 30.1 degrees +/- 2.2 degrees C. Chest tube drainage during the first 24 hours was 525 +/- 220 mL. Mean ventilation time was 54 +/- 22 hours. Elevation of serum lactate levels at 1, 12, and 24 hours postoperatively rose to 22 +/- 14, 18 +/- 11, and 19 +/- 8 mg/dL respectively. We observed new postoperative permanent neurologic deficits in 5 patients (4.2%) and TND in 3 patients (2.5%). The 30-day mortality rate was 5% (n = 6). After a mean follow-up period of 2.8 years, 104 patients (87%) were still alive. CONCLUSIONS Antegrade cerebral perfusion in combination with mild hypothermia offered sufficient neurologic protection in our patient cohort, provided adequate distal organ protection, and reduced perioperative complications in surgery for type A dissection. This perfusion strategy may help in reducing perioperative complications in this particular patient population.

Awake coronary artery bypass grafting: utopia or reality?

BACKGROUND Off-pump coronary artery bypass grafting (OPCAB) was implemented to reduce trauma during surgical coronary revascularization. High thoracic epidural anesthesia further reduced intraoperative stress and postoperative pain. This technique also supports awake coronary artery bypass (ACAB), completely avoiding the drawbacks of mechanical ventilation and general anesthesia in high-risk patients. We compared our first results of the ACAB procedure with the conventional OPCAB operation. METHODS Thirty-five patients underwent ACAB (group A) with left internal mammary artery to left anterior descending coronary artery grafting using a partial lower ministernotomy (n = 25) or double bypass grafting (n = 9) and even triple vessel coronary artery revascularization (n = 1) through complete median sternotomy. Thirty-four patients (group B), matched for age, sex, and comorbidity with group A, underwent either partial lower ministernotomy (n = 24) or OPCAB by complete sternotomy (n = 10). We recorded clinical outcomes and postoperative visual analog scale pain scores. RESULTS In group A, 32 patients remained awake throughout the entire procedure. Three patients required secondary intubation because of incomplete analgesia (n = 1) or pneumothorax (n = 2). Patients in group A had a recovery room stay of 6.0 +/- 3.2 hours. In group B, mechanical ventilation was implemented for 4.8 +/- 3.1 hours and intensive care unit stay lasted 12 +/- 6.8 hours. Group A had no in-hospital deaths, compared with 1 death in the conventional OPCAB group. Each group had 1 patient with graft stenosis detected on the predischarge angiogram. Early postoperative pain was significantly less in group A than in group B (visual analog scale of 32 +/- 8 compared with 58 +/- 11, p < 0.0001). CONCLUSIONS The present data demonstrate the feasibility and safety of surgical coronary revascularization without general anesthesia. Continuation of thoracic epidural analgesia provides better pain control and faster mobilization after such procedures. Surprisingly, the ACAB procedure was well accepted by the patients.

Computer-enhanced totally endoscopic sequential arterial coronary artery bypass.

Minimally invasive coronary artery bypass grafting of the anterior wall using a left anterior small thoracotomy became a routine procedure within the last 3 years. The introduction of robotics into the cardiosurgical practice in 1998 has finally enabled totally endoscopic closed chest procedures. We report two patients with totally endoscopic left internal thoracic artery bypass grafting to the left anterior descending artery and the first diagonal branch in sequential arterial revascularization technique using the daVinci surgical system.

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.

Biventricular pacing for weaning from extracorporeal circulation in heart failure

Resynchronization of the intra- and interventricular conduction by biventricular pacing has been suggested in patients with end-stage heart failure. We present a case in which extracorporeal circulation could only be weaned after placement of an additional left ventricular pacing wire. Biventricular stimulation led to normal motion of the anterior wall and a previously bulging interventricular septum; this improved the hemodynamic situation significantly.

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.

Segmental wall motion abnormalities during telerobotic totally endoscopic coronary artery bypass grafting.

In addition to single-lung ventilation (SLV), intrathoracic CO2 insufflation is mandatory for adequate exposure during totally endoscopic coronary artery bypass grafting. With transesophageal echocardiography, we investigated biventricular myocardial wall motion in 25 patients with isolated disease of the left anterior descending coronary artery who underwent totally endoscopic coronary artery bypass grafting with the “Da Vinci” robotic surgical system. At distinct time points during the operation, a cine loop of both ventricles was registered from a transgastric mid-short-axis view. Myocardial wall motion analysis was performed according to an established segmentation model of the left ventricle and to an established five-point scale for wall motion (1, normal; 5, dyskinesia). Significant alterations from preoperative baseline wall motion were visible in the septal, inferior, and anterior segments of the left ventricle at some time during the prebypass period, combined with a markedly decreased Pao2 under SLV and increased intrathoracic pressure. The same findings applied to the right ventricle; however, wall motion abnormalities were more pronounced here. After myocardial revascularization, weaning from cardiopulmonary bypass, CO2 deflation, and return to double-lung ventilation, myocardial wall motion recovered to baseline values. Clinically significant hemodynamic instability did not occur. The data suggest that robot-assisted coronary artery bypass grafting leads to significant prebypass alterations of biventricular segmental wall motion. On the basis of our data, it cannot be definitively stated whether the observed results were due to reduced oxygenation during SLV and thus “real” myocardial ischemia, intrathoracic CO2 insufflation with positive pressure leading to mechanical compromise of the heart, absolute or relative hypovolemia, or a combination of these factors. However, in this cohort, which consisted of patients with single-vessel disease and good ventricular function, these changes were of limited clinical relevance.

Coronary artery bypass grafting via sternotomy in conscious patients.

The application of high thoracic epidural anesthesia (TEA) as an adjunct to general anesthesia is increasingly being used for coronary artery bypass grafting (CABG) with extracorporeal circulation. Recent developments in beating heart techniques rendered the sole use of TEA in conscious patients possible, and have been reported for single-vessel beating heart CABG via lateral thoracotomy. For multi-vessel revascularization, the heart is usually approached via sternotomy; therefore, the sole use of TEA was applied in awake patients who underwent CABG via sternotomy. A total of 7 patients scheduled for awake coronary artery bypass grafting (ACAB) received TEA via an epidural catheter placed at the levels of T1–2 or T2–3, respectively. Total arterial myocardial revascularization was performed after partial lower sternotomy. Besides standard monitoring, anesthetic levels were determined using an epidural scoring scale for arm movements (ESSAM). While 6 patients were awake and spontaneously breathing during the entire procedure, one patient had to be intubated intraoperatively because of respiratory distress caused by phrenic nerve palsy. Hemodynamics were stable throughout the operation. No significant arterial hypercarbia occurred. All patients rated TEA as “good” or “excellent.” We could demonstrate that the single use of TEA for CABG via sternotomy was feasible and that the patients felt well, were painfree, and remained hemodynamically stable. High patient satisfaction in our small and highly selected cohort can be reported. Because beating heart surgery in a conscious patient still carries a significant risk, further randomized controlled trials are mandatory to definitively evaluate the role of sole TEA in cardiac surgery.