Stephan Schueler

Technique of closed chest coronary artery surgery on the beating heart

OBJECTIVEnThe application of an endoscopic stabilizer (Intuitive Surgical, Mountain View, CA, USA) enables closed chest off-pump coronary artery bypass via a four-point stab incision avoiding sternotomy and minithoracotomy.nnnMETHODSnBetween May 1999 and January 2001 we operated upon a total of 37 patients (five female, 32 male, median age 62+/-9 years) suffering from coronary artery disease using totally endoscopic coronary artery bypass (TECAB), whereas an initial series of eight TECAB patients was operated upon using an endovascular bypass system (Heartport). The da Vinci surgical system was used in order to perform left internal mammary artery (LIMA) or right internal mammary artery (RIMA) harvesting and anastomoses on a beating heart in 29 patients (four female, 25 male, median age 64+/-9.8 years). Altogether 26 patients suffering from single-vessel coronary artery disease (SVCAD) were revascularized applying LIMA to the left anterior descending artery (LAD) and three patients with two diseased coronary vessels received bilateral internal mammary artery grafting (BIMA), respectively.nnnRESULTSnIn this series we had a 100% survival rate. Conversion rate to a median sternotomy was 3.4%. Patients were operated upon via four 1-cm chest incisions using the da Vinci robot for LIMA or BIMA harvesting and for performance of anastomoses on the beating heart. In the overall series of 56 patients intended to be treated by TECAB, 19 (33.9%) were converted to a minimally invasive direct coronary artery bypass procedure.nnnCONCLUSIONnThis new robotic-enhanced surgical technique promotes an optimistic way of thinking about the further development of this procedure and its application in patients suffering from single-vessel CAD.

Interleukin-1, interleukin-6 and myocardial enzyme response after coronary artery bypass grafting – a prospective randomized comparison of the conventional and three minimally invasive surgical techniques

OBJECTIVEnIn order to evaluate the traumatic effects of median sternotomy and cardiopulmonary bypass (CPB) in conventional and minimally invasive coronary artery bypass grafting, inflammatory response was studied in a prospective randomized trial in patients referred to single-vessel coronary artery bypass grafting.nnnMETHODSnFour surgical techniques were compared: group 1, median sternotomy with CPB in ten patients (eight male, two female; aged 59.6+/-11.0 years (mean+/-SD)); group 2, median sternotomy and off-pump in ten patients (seven male, three female; aged 65.1+/-10.0 years); group 3, minithoracotomy with CPB in ten patients (seven male, three female, aged 61.2+/-10.4 years); group 4, minithoracotomy and off-pump in ten patients (nine male, one female, aged 62.9+/-9.8 years). All patients received a left internal mammary artery graft to the left anterior descending artery (LAD). Clinical data, perioperative values of cytokines and cardiac enzymes were monitored.nnnRESULTSnThere were no major complications. Troponin-T and creatine kinase isoenzyme MB (CK-MB) levels were significantly higher in CPB procedures (P<0.0056; multivariate general linear model). Interleukin-6 (IL-6) levels were significantly higher in minithoracotomy procedures. Interleukin-1 (IL-1) was significantly increased in all patients compared with the preoperative values.nnnCONCLUSIONSnThe use of CPB is combined with higher levels of troponin-T and CK-MB as signs of myocardial damage. Surgical access was identified as a trigger of inflammatory response, as minithoracotomy is related to higher levels of IL-6. IL-1 increased in all procedures and this occurred independently of the surgical access or the use of CPB, which points out a potential relationship between inflammatory response and anesthesia. Neither CPB nor surgical access influenced the clinical outcome in the treatment of coronary artery single-vessel bypass grafting.

Clinical experiences with minimally invasive mitral valve surgery using a simplified port accessTM technique

OBJECTIVEnUsing the initial experiences with the Port-Access technique for the treatment of mitral valve disease some changes were made thus resulting in more simple and faster procedures.nnnMETHODSnTwenty-nine patients (13 male, 16 female, aged 30 to 75 years, median 62.5 +/- 11.0 years) underwent minimally invasive mitral valve surgery between May 1996 and December 1997. The underlying diseases were: mitral valve insufficiency (n = 16), mitral valve stenosis (n = 7) and combined mitral valve disease (n = 6). Through a small right thoracotomy (5-7 cm) access to the pericardium and the heart was gained. Cardiopulmonary bypass was instituted through femoral cannulation and an intraaortic balloon-catheter was introduced for aortic occlusion, aortic root venting and delivery of cold crystalloid cardioplegia. Mitral valve repair (five patients) or replacement (24 patients) was performed.nnnRESULTSnThere was no death during the whole follow-up period. There was no perivalvular leak and only minor residual mitral valve regurgitation was observed on intraoperative or postoperative (3 months) transesophageal echocardiography in three patients. There was no postoperative study-related complication. Time of ventilation and intensive care unit were comparable with the data of patients undergoing conventional mitral valve surgery but hospital stay was shorter in the last 10 consecutive cases.nnnCONCLUSIONSnThis simplified technique of mitral valve surgery combines the advantage of less invasive operative and good cosmetic results with the safety of conventional mitral valve surgery. At our institution this technique presents in well selected patients suffering from mitral valve disease the procedure of choice.

Minimally invasive mitral valve surgery – clinical experiences with a PortAccess system

OBJECTIVEnThis is the initial experience with a new minimally invasive surgical technique for the treatment of mitral valve disease using a PortAccess system.nnnMETHODSnBetween May 1996 and May 1997, 21 patients (nine male, 12 female, aged 30-75 years, median 64 years) underwent minimally invasive mitral valve surgery. The underlying diseases were: mitral valve insufficiency (n = 11), mitral valve stenosis (n = 5) and combined mitral valve disease (n = 5). Through a small right thoracotomy (6-8 cm) access to the pericardium and the heart was gained. Cardiopulmonary bypass was instituted through femoral cannulation and an intraaortic balloon-catheter (Heartport Inc., Redwood City, CA) was introduced for aortic occlusion, aortic root venting and delivery of cold crystalloid cardioplegia. Mitral valve repair (four patients) or replacement (15 patients) was performed.nnnRESULTSnThere was no death during the whole follow-up period. There was no perivalvular leak and only minor residual mitral valve regurgitation was observed on intraoperative or postoperative (3 months) transesophageal echocardiography. There was no postoperative study-related complication. Time of ventilation, intensive care unit and hospital-stay were comparable with the data of patients undergoing conventional mitral valve surgery.nnnCONCLUSIONSnThis technique of PortAccess mitral valve surgery combines the advantage of less invasive operative trauma with the safety of conventional mitral valve surgery.

Anti-Proliferative Properties of the Phosphodiesterase-4 Inhibitor Rolipram Can Supplement Immunosuppressive Effects of Cyclosporine for Treatment of Obliterative Bronchiolitis in Heterotopic Rat Allografts

BACKGROUNDnPotent prevention and therapy of obliterative bronchiolitis may enhance long-term survival after lung transplantation. Phosphodiesterase-4 inhibitors have been established for anti-inflammatory treatment, particularly of pulmonary diseases. Using a heterotopic rat model, the effect of rolipram was investigated and compared with cyclosporine for epithelium disturbance and leukocyte infiltration and proliferation, which are key events in the development of obliterative bronchiolitis.nnnMETHODSnTracheae were transplanted into the omentum of allo- and syngeneic animals. Four allogeneic groups were investigated: treatment with rolipram; treatment with cyclosporine; treatment with a combination of rolipram and cyclosporine; and untreated (60-day time course). Using histo- and immunohistochemical stainings, epithelium disturbance, leukocyte subsets, proliferating cells and luminal occlusion were quantified by digital morphometry.nnnRESULTSnIn rolipram-treated animals, the epithelium was completely disturbed until Day 14. It was temporarily preserved in rats that received cyclosporine until Day 60. In the acute phase (Day 5), infiltration of monocytes/macrophages was significantly inhibited by rolipram, but less effective than in cyclosporine-treated rats. At later timepoints (Days 28 and 60), rolipram significantly inhibited proliferation, in contrast to enhanced proliferation of fibroblast-like cells after cyclosporine treatment. The combination of rolipram and cyclosporine led to temporary epithelial preservation and effective inhibition of leukocyte infiltration (Day 5) and proliferation (Days 28 and 60). Luminal occlusion was significantly reduced in the combination group compared with the cyclosporine-only group.nnnCONCLUSIONSnAlthough cyclosporine temporary protects epithelial integrity by the inhibition of acute rejection, rolipram showed greater potency for long-term inhibition of mesenchymal-cell proliferation. The combination of both drugs may be useful for limiting chronic obliterative changes after lung transplantation.

Three‐Year Follow‐Up After Port‐Access Mitral Valve Surgery

Abstract Introduction: After the promising early results with Port‐Access mitral valve (MV) surgery, the mid‐term results were evaluated. Methods: Among 31 patients receiving this surgery, there were two subgroups (A and B). The 14 patients in group A (7 men, 7 women, 64.0 ± 12.8 years, LVEF 0.62 ± 0.118) received the procedure exactly as proposed by Heartport. The 17 patients in group B (6 men, 11 women, 63.0 ± 11.48 years, LVEF 0.61 ± 0.117) received a modified technique for a low complex procedure. The underlying diseases were MV insufficiency (n = 14), MV stenosis (n = 9), and combined MV disease (n = 8). One female patient had a partial atrial ventricular canal. Results: Perioperative mortality was 3.2%. Survival at 39.0 ± 6.3 months (median ± SEM) was 93.5%. Two patients required intraoperative inotropic and mechanical support (intro‐aortic balloon pump [IABP]). One of these two patients died on postoperative day 3 due to low cardiac output syndrome. All ther patients survived the procedure. Twenty‐four patients underwent MV replacement, 7 patients recalved MV repair, and 1 patient received, in addition, ASD repair. In group B, operative time, ICU stay, and hospitalization was shorter. Conclusions: Good early results after Port‐Access MV surgery were confirmed by equal mid‐term results. The patients are satisfied with the surgical and the cosmetic results, however, Port‐Access MV surgery still has to prove superior outcome compared to conventional MV surgery. In selected cases a true reduction of the surgical trauma is possible.

Experiences with a minimally invasive surgical technique for the treatment of coronary artery multivessel disease in 100 patients.

OBJECTIVEnThe treatment of coronary single vessel disease under minimally invasive surgical conditions was followed by the treatment of coronary multivessel disease using a new technique.nnnMETHODSnUsing this technique 100 patients (80 male, 20 female, median age 61.0+/-8.9 years, ranged from 39 to 82 years) with coronary single vessel disease, double vessel disease or multivessel disease were treated between November 1996 and December 1997. Via a small (6-9 cm) left lateral chest incision in the second or third intercostal space, the left internal thoracic mammary artery (LIMA) was harvested and access to the central portion of the heart including the ascending aorta was obtained. In parallel, saphenous vein segments were harvested. Arterial cannulation was instituted via the ascending aorta, thus avoiding retrograde flow. In all patients except three the LIMA was used for the left anterior descending artery (LAD). In addition vein grafts were used for revascularization of the other coronary arteries. All cardiac anastomoses were performed during cardioplegic arrest after external aortic cross clamping and antegrade application of cardioplegia.nnnRESULTSnNo death or intraoperative complications were observed in this series. The median hospital stay was 6.0+/-1.4 days (median+/-SEM). Postoperative complications were reexplored for bleeding (n = 1), delayed wound healing (n = 2), wound infections (n = 4), lymphatic fistulas (n = 4), and a chest wall hernia (n = 1).nnnCONCLUSIONSnThis minimally invasive surgical technique presents a safe alternative to conventional coronary artery surgery avoiding sternotomy related complications and decreasing hospital stay and morbidity.

Clinical Experience with Minimally Invasive Coronary Artery and Mitral Valve Surgery with the Advantage of Cardiopulmonary Bypass and Cardioplegic Arrest Using the Port Access Technique

Abstract. To minimize surgical trauma, the use of Port Access cardiac surgery was initiated in patients (pts) with coronary artery disease (CAD) (42 pts) or mitral valve disease (MVD) (24 pts) in March 1996 at our institution. Altogether 42 pts (36 men, 6 women; age 31–75 years, median 59.0 years) with isolated lesions of the left anterior descending (LAD) artery underwent Port Access coronary artery surgery (PACAS). A small (5–9 cm) incision was done parasternally on top on the fourth rib. The left internal mammary artery (LIMA) was dissected through the minithoracotomy or by using an additional thoracoscopic approach. A total of 24 pts (12 men, 12 women; age 30–75 years, median 62 years) underwent Port Access mitral valve surgery (PAMVS). In these pts the procedure was performed through a small right thoracotomy (6–8 cm). In all cases, endovascular cardiopulmonary bypass (CPB) was instituted through femoral cannulation, and an additional endoaortic balloon catheter was introduced into the ascending aorta for aortic occlusion. In pts with PACAS the survival was 98% (41/42) and in the PAMVS group 100%. All pts but one survived the PACAS and are well today. There were no deaths in the PAMVS group. The hospital stay was reduced by 1 day on average after PACAS and 3 days after PAMVS. Thus in well selected patients Port Access cardiac surgery represents a safe and feasible minimally invasive surgical approach that avoids the potential complications of a sternotomy while offering the advantages and safety of CPB and cardioplegic arrest. This minimally invasive approach offers a shortened hospital stay and earlier rehabilitation.

MINIMALLY INVASIVE CARDIAC SURGERY FOR THE TREATMENT OF CORONARY ARTERY MULTI-VESSEL DISEASE

OBJECTIVEnIn order to avoid sternotomy-related complication after cardiac surgery minimally invasive cardiac surgery has been developed successfully for the treatment of coronary artery disease, however, those techniques were still limited to the treatment of single-vessel disease. Therefore a new surgical technique for the treatment of multi-vessel disease has been developed.nnnMETHODSnFrom November 1996 to May 1997 61 patients (age 39-78 years) with coronary artery disease were treated with this new technique. This technique included a small (6-9 cm) left lateral chest incision via the 3rd intercostal space. The left internal thoracic mammary artery (LIMA) was harvested through the chest incision and access to the central portion of the heart including the ascending aorta was obtained. During LIMA harvesting saphenous vein segments were harvested. Cardiopulmonary bypass was instituted through femoral vein cannulation and cannulation of the ascending aorta in most cases. After external aortic cross clamping cold antegrade cardioplegia was applied. In all patients except one the LIMA was used for the left anterior descending artery (LAD). In addition vein grafts were used for revascularisation of the other coronary arteries.nnnRESULTSnThere were no intraoperative complications and all patients survived the procedure. All patients could be weaned from CPB and the postoperative course was uneventful in most patients. Wound complication occurred in two patients. The median hospital stay was 6 days (median +/- SEM).nnnCONCLUSIONSnThis new technique combines minimally invasive surgical conditions with the safety standards of routine cardiac surgery. With this approach even extensive coronary artery disease can be treated.

Protective mechanisms of radical scavengers vitamins C&E in an in-vivo pig model of pulmonary reperfusion injury

PO TID x 10 wk) was used for comparison. Costs were based on average wholesale drug price and list price for serial PCR monitoring for 3 mo. Results: Each group consisted of 9 LTR. In the first 3 mo., primary CMV infxn occurred in 5/9 PRE and 1/9 GPX LTR. In each group, 1 case of primary CMV infxn occurred between 3-12 mo post-LT, resulting in 6 primary cases in the PRE and 2 in the GPX groups. Recurrent CMV infxn occurred in 4/6 PRE and 1/2 GPX LTR within the first yr post-LT. In the first 3 mo, 8 cases of HSV infxn occurred in the PRE LTR vs. none in the GPX LTR. In the PRE group, mean cost per pt for PCR monitoring and CMV Rx in the first 3 mo was