Biomedical subjects

A Diegeler

Publications and source records attributed to A Diegeler.

At least 19 recordsLinked to original sources

PubMed2002

Mediastinitis and cardiac surgery--an updated risk factor analysis in 10,373 consecutive adult patients.

BACKGROUND: Deep sternal wound infection (DSWI) remains a serious complication after cardiac surgery. New evolving techniques including the utilization of internal mammary arteries (IMA), beating heart procedures, and minimal invasive surgery (MIC) require an updated risk factor analysis to identify high risk patients in order to improve perioperative treatment. METHODS: 10,373 consecutive patients receiving cardiac surgery between May 1996 and August 1999 were evaluated: 9,303 underwent full sternotomy whereas a minimally invasive (MIC) approach using partial sternotomy or lateral thoracotomy was used in 1,070 patients. DSWI was defined as the evidence of mediastinitis seen at reoperation along with one or more of the following: positive culture of mediastinal fluid, positive blood culture or temperature higher than 38 degrees C and/or leukocytosis. RESULTS: The overall incidence of DSWI in the "full sternotomy" group was 1.44 % (134 of 9,303). Univariate risk factor analysis showed a significant influence of IMA use, ICU / IC treatment > 5 days, postoperative ventilator time > or = 72 h, need for reexploration, diabetes, surgery time > or = 180 min, assist device implantation (including use of IABP), peripheral vascular disease and increased body mass index. Multivariate analysis identified double IMA, ICU treatment > 5 days, single IMA, diabetes, reexploration and increased body mass as significant risk factors. No mediastinitis was observed in the MIC group. CONCLUSION: As DSWI is related to sternotomy, a MIC approach should be considered for patients at high risk for DSWI. IMA takedown as a pedicled graft should be especially avoided in patients with diabetes since the risk for postoperative mediastinitis is unacceptably high in this patient group.

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PubMed2001

Transmyocardial laser revascularization with the holmium:YAG laser: loss of symptomatic improvement after 2 years.

OBJECTIVE: Whether transmyocardial laser revascularization (TMLR) provides a long-term benefit in terms of relief of angina, improvement of exercise tolerance, left ventricular function, and myocardial perfusion. METHODS: Forty-one patients underwent TMLR using a holmium:YAG-laser, 14 as TMLR alone (group A), 27 with additional aortocoronary bypass grafting (group B). Follow-up was obtained at 6, 12, 18, 24, and 36 months in this prospective study. RESULTS: In group A patients CCS-class improved up to 18 months postoperatively, after 24 and 36 months postoperatively there was absence of a positive effect of TMLR: the CCS-class decreased to 2.4 as compared to 3.5 preoperatively After combined CABG and TMLR (group B) there was a significant decrease in angina at all times. The CCS-functional class in these patients was 1.7 at 36 months as compared to 3.5 preoperatively. There was no significant change in exercise tolerance as compared to preoperatively. Left ventricular ejection fraction did not improve in either of the groups. Thallium scintigraphy indicated no improvement in myocardial perfusion in laser treated areas. The perioperative mortality was 0%, the late mortality rate was 36% in group A and 11% in group B. CONCLUSIONS: In our experience, in the vast majority of patients who are subjected to TMLR alone the benefit of reduction or relief of angina and improvement in quality of life is only temporary. In addition there is no improvement in objective clinical parameters. We believe that TMLR should only be used in patients with severe angina refractory to medical treatment and requiring a symptomatic therapy.

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PubMed2001

A new intracardiac microaxial pump: first results of a multicenter study.

As coronary artery bypass grafting (CABG) surgery in the beating heart technique is progressing, new devices have been developed to overcome hemodynamic instabilities while tilting the heart for exposure of back wall vessels. A new device for in heart biventricular intracorporeal circulation was applied in 42 patients undergoing CABG surgery (Group 1). The control group consisted of 38 patients operated on using a conventional cardiopulmonary bypass setup (Group 2). The study protocol of the prospective, randomized multicenter study was approved by the local ethics committees. Patients were included following inclusion criteria and patient informed consent. Mean age, procedure time, mean arterial pressure (MAP), and hemolysis by means of plasma free hemoglobin (fHb) were assessed preoperatively, perioperatively, on postoperative Days 1 to 3, at discharge, and at a 3 month follow-up. The mean age was 62.1 (range 59-74) years (Group 1), 62.7 (range 48-72) years (Group 2); procedure time was 112 min +/- 31.9 min (Group 1), 137.4 min +/- 36.2 min (Group 2); and 2.3 +/- 0.6 (Group 1), 2.2 +/- 0.7 (Group 2), vessels were revascularized. The flow on pump was 3.7 (2.5/4.4) L/min (Group 1), 4.9 (3.6/6.2) L/min (Group 2) which resulted in a MAP of 69.8 (4.0/143) mm Hg (Group 1), 58.3 (5.3/94) mm Hg while assessing the vessels of the back wall. Hemolysis defined by fHB was lower than 20 mg/dl at all times pre- and postoperatively. Intraoperative maximum values were up to 100 mg/dl in 4 patients (2 in Group 1 and 2 in Group 2). Body mass index was 26.4 +/- 2.6 (Group 1), 27.9 +/- 3.2. New York Heart Association Class was II to III in both groups. There were no pump related life threatening or severe adverse events. Beating heart procedures with ICC can be reliably and safely achieved. As the device is easy to use, it may deserve a more widespread use in the future.

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PubMed2001

Computer-enhanced "robotic" cardiac surgery: experience in 148 patients.

OBJECTIVE: A computer-enhanced instrumentation system was used in 148 patients to minimize access in cardiac surgical procedures. METHODS: The da Vinci telemanipulation system (Intuitive Surgical, Mountain View, Calif) provides a high-resolution 3-dimensional videoscopic image and allows remote, tremor-free, and scaled control of endoscopic surgical instruments with 6 degrees of freedom. By April 2000, the system had been used in 131 patients for coronary artery bypass grafting and 17 patients for mitral valve repair. In the coronary bypass group, the system was used in one of three ways: (1) to take down the internal thoracic artery followed by a minimally invasive direct coronary bypass procedure (n = 81); (2) to perform the anastomosis between the internal thoracic artery and the left anterior descending coronary artery in standard-sternotomy coronary bypass (n = 15); or (3) for total endoscopic coronary artery bypass grafting to anastomose the left internal thoracic artery to the left anterior descending on the arrested heart (n = 27) or the beating heart (n = 8). In 17 patients with nonischemic mitral valve insufficiency the mitral valve was repaired. Closed-chest cardiopulmonary bypass with cardioplegic arrest (Port-Access technique; Heartport, Inc, Redwood City, Calif) was used for arrested-heart total endoscopic coronary bypass and mitral valve repair. RESULTS: The da Vinci system allows for precise tissue handling and enables the endoscopic performance of cardiac surgical tasks that require a high degree of dexterity (coronary anastomosis, mitral valve repair). No technical mishaps have occurred. The internal thoracic artery was successfully taken down in 79 of 81 patients in the group undergoing minimally invasive coronary bypass and, after a steep learning curve, is currently performed in less than 40 minutes. The postoperative patency rate is 96.3%. Total endoscopic coronary bypass was completed in 22 of 27 cases with 95.4% patency as demonstrated by angiography at 3 months' follow-up. Closed-chest endoscopic beating-heart bypass grafting was successfully performed in 2 out of 8 patients with the use of a new endoscopic stabilizer. In the group having mitral valve repair, primary endoscopic computer-enhanced repair was successfully completed in 14 of 17 patients; three others had to be changed to a standard endoscopic technique, including 1 who required valve replacement. At 3 months' follow-up, 1 additional patient underwent early reoperation for recurrent mitral insufficiency. Overall early and late mortality in this cohort of 148 patients was 2.0% and was not related to the use of the system. CONCLUSION: In conclusion, computer-enhanced endoscopic cardiac surgery can be performed safely in selected patients. Internal thoracic artery takedown is now routinely performed with good results. Total endoscopic coronary bypass is feasible on the arrested heart but does not offer a major benefit over the minimally invasive direct approach because cardiopulmonary bypass is still required. The early clinical experience with closed-chest beating-heart bypass grafting outlines the limitations of this approach despite some procedural success.

Animals↗

PubMed2000

Prospectively randomized comparison of different mechanical aortic valves.

BACKGROUND: The aim of this prospectively randomized study was to evaluate the hemodynamic and functional outcomes after aortic valve replacement with 3 different bileaflet mechanical valves. METHODS AND RESULTS: Three hundred consecutive patients were randomly assigned to receive ATS (n=100), Carbomedics (n=100), or St Jude Medical Hemodynamic Plus (n=100) mechanical aortic valve replacement. There were no significant differences regarding patient age (average 61+/-8 years), body surface area (1.9+/-0.2 m(2)), left ventricular function (ejection fraction 0.59+/-0.17), and presence of aortic stenosis (90%, 89%, and 91%), respectively. All patients had postoperative as well as 6-month and 1-year follow-ups that included transthoracic echocardiography. Multivariate statistical analysis was performed. Implanted valve sizes were comparable at 24+/-2 (ATS), 23.7+/-1.6 (CM), and 23.6+/-1.9 (SJMHP) mm (NS). At 1-year follow-up, the following incidence of events was noted: death 3/1/1, all non-valve related; stroke 0/1/1; trivial transvalvular incompetence 3/3/2; paravalvular leak 2/3/2; and reoperation 0/1/1, respectively (NS). Transvalvular flow velocities were 2.5/2.6/2.4 m/s postoperatively (P:=0.03) and 2.4/2.4/2.3 m/s at 6-month follow-up, respectively (NS). There was a significant decrease in left ventricular mass for all patients but no significant differences among the groups. CONCLUSIONS: There are no clinically relevant differences among the tested bileaflet aortic valves. Regardless of valve type, there was a low complication rate. On the basis of these findings, all 3 bileaflet prostheses are well suited for aortic valve replacement.

Aortic Valve↗

PubMed2000

Humoral immune response during coronary artery bypass grafting: A comparison of limited approach, "off-pump" technique, and conventional cardiopulmonary bypass.

BACKGROUND: The introduction of limited approaches to the heart and the avoidance of cardiopulmonary bypass (CPB) aim to reduce the invasiveness of CABG by decreasing the systemic release of inflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-8, as well as the anti-inflammatory agent IL-10. This study compares the humoral immune response in patients undergoing CABG with standard, minimally invasive, and "off-pump" techniques. METHODS AND RESULTS: Thirty patients were divided into 3 operative groups: full sternotomy approach plus CPB (group A); full sternotomy approach, off pump (group B); and limited left anterior thoracotomy, off pump (group C). Plasma levels of TNF-alpha receptors p55 and p75, IL 6, IL-8, and IL-10 were taken at baseline, during CPB, and at 4, 24, and 48 hours and 6 days after surgery. A significant increased release of activated complement factors C5a and C3d, IL-8, and IL-10 was observed in patients subjected to CPB (group A) during the initial period and for a short time after perfusion (P:<0.05). TNF-alpha receptors p55 and p75 showed a prolonged elevation (up to 48 hours) in the CPB group compared with the 2 off-pump groups. IL-6 showed no different release among the 3 surgical groups throughout the entire period. There was no significant difference in any parameter measured in relation to the type of operative approach. CONCLUSIONS: There is an inflammatory, as well as an anti-inflammatory, response during CABG that is related to the general surgical trauma. The release of immune mediators is enhanced by the use of CPB during various perioperative and postoperative phases. The type of operative approach did not influence this immune response.

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PubMed2000

Minimally invasive saphenous vein harvesting techniques: morphology and postoperative outcome.

BACKGROUND: Conventional saphenous vein harvest is associated with numerous complications, which may be reduced by minimally invasive vein-harvesting techniques. The integrity of the venous endothelium must be guaranteed before using new saphenous vein harvesting techniques. This short-term study compared the clinical outcome of two minimally invasive techniques with the conventional technique, and compared morphology as documented by light and electron microscopy. METHODS: Ninety-two patients were prospectively randomized into three groups. Two different minimally invasive techniques of greater saphenous vein harvesting were used in sixty-two patients. One used a video-assisted dissector (group A, n = 31), and one used a light-coupled retractor (group B, n = 31). Thirty patients were treated by the conventional technique (group C). RESULTS: Incision lengths were 7.6+/-2.1 cm in group A and 9.3+/-3.2 cm in group B, as compared with 38.9+/-8.7 cm in the conventional group. Harvesting time was prolonged by a mean of 26% when using a minimally invasive technique. Conversion rate to the open technique was 3 of 31 (9.3%) in group A and 2 of 31 (6.2%) in group B. No wound complications were noted in group A, but one wound inflammation was seen in group B; only a mild hematoma was seen in both groups. Edge necrosis, wound separation and inflammation were noted in the conventional group. Light and electron microscopy revealed no significant denudation of the endothelial layer in groups A and B as compared with group C. CONCLUSIONS: These data show an excellent postoperative result when using the minimally invasive technique as compared with the conventional group. The safety of the technique is demonstrated by the preservation of endothelial integrity.

Feasibility Studies↗

PubMed2000

Pain is significantly reduced by cryoablation therapy in patients with lateral minithoracotomy.

BACKGROUND: In minimally invasive cardiac surgery use of a lateral minithoracotomy is associated with early postoperative rehabilitation but also relatively high pain levels during the first 3 postoperative days. Cryoablation therapy was evaluated prospectively. METHODS: From April 1999 until September 1999, 57 patients underwent lateral minithoracotomy for mitral valve operation (n = 18) or minimally invasive direct coronary artery bypass grafting (n = 39). Intraoperatively, patients were randomly assigned to cryoablation or intercostal application of local anesthetic agents. A standardized questionnaire was used for prospective pain assessment on postoperative days 1 to 7. RESULTS: From postoperative day 1 to 7 pain levels declined in all groups. Overall pain levels were significantly lower in the cryo group than in the control group (p < 0.0001, GLM). According to diagnoses, pain levels were significantly lower after MIDCABG and cryo versus control; after mitral valve operation they were lower in the cryo group and almost reached significance. CONCLUSIONS: Cryoablation is easy to perform and leads to a significant reduction in pain and lower request for additional pain medication after lateral minithoracotomy in minimally invasive cardiac operation.

Anesthetics, Local↗

PubMed2000

Combined stentless mitral valve implantation and radiofrequency ablation.

BACKGROUND: The aim of this study was to evaluate the results of combined stentless mitral valve (SMV) replacement and intraoperative radiofrequency ablation for chronic atrial fibrillation (IRAAF) to restore physiologic hemodynamic function. METHODS: Since July 1998 12 patients (72+/-4 years, 10 women, mitral stenosis/mitral incompetence 8/4, NYHA 3.3+/-0.4, CI 1.8+/-0.5) had SMV implantation and received additional IRAAF by inducing continuous left atrial lesion lines from the MV annulus to all four pulmonary veins and to the atriotomy. RESULTS: The flexible SMV was implanted at the papillary muscles and at the annulus using a conventional (n = 6) or a minimally invasive approach (n = 6). Sinus rhythm was successfully restored in 10 of 12 patients with 6- and 12-months' follow-up; 2 required DDD-pacemaker implantation. However, in the early postoperative period several interventions including medical treatment (sotalol or amiodarone) in 9 and electrical cardioversion in 7 patients was required. Two patients required reinterventions: 1 cardioversion and 1 amiodarone medication after 3 and 6 months, respectively. At echocardiography the SMV demonstrated good hemodynamic function and atrial contraction. CONCLUSIONS: Restoration of physiologic cardiac function by SMV implantation and IRAAF is advantageous and no further anticoagulation is required.

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PubMed2000

Neuromonitoring and neurocognitive outcome in off-pump versus conventional coronary bypass operation.

BACKGROUND: Cardiopulmonary bypass seems to be a major cause for both intraoperative microemboli and cerebral hypoperfusion. This study investigates high intensive transient signals (HITS) in transcranial Doppler ultrasound (TCD) and serum levels of the neurobiochemical marker protein S-100 in patients who underwent coronary artery bypass operation without cardiopulmonary bypass (off-pump CABG) in comparison with the conventional procedure using cardiopulmonary bypass (CPB). The results are related to the neuropsychologic outcome in both surgical groups. METHODS: Forty patients were randomized in 2 groups (20 conventional and 20 off-pump CABG). Neurocognitive status was assessed preoperatively and postoperatively. Venous serum levels of S-100 protein were measured before and after coronary operation, HITS were measured in the middle cerebral artery during the operation. RESULTS: The median value of HITS was 394.5 (0 to 2217) in the conventional versus 11 (0 to 50) in the off-pump group, p less than 0.0001. Postoperative S-100 serum levels were: 3.76 (0.13 to 11.2) microg/L (conventional) versus 0.13 (0.04 to 1.01) microg/L (off-pump), p less than 0.0001. Postoperative cognitive testing showed significantly different results with a postoperative impairment of 90% of the patients in the conventional group versus no impairment in the off-pump group. CONCLUSIONS: Cognitive impairment seems to be strongly associated to CPB and the occurrence of micro-emboli. The off-pump technique appears to be promising in order to eliminate the source of these neuropyschologic impairments following CABG operation.

Cardiopulmonary Bypass↗

PubMed2000

The revival of surgical treatment for isolated proximal high grade LAD lesions by minimally invasive coronary artery bypass grafting.

BACKGROUND: Percutaneous coronary angioplasty (PTCA) and stent implantation have become the first-line intervention for patients with isolated proximal LAD-lesions. Minimally invasive direct coronary artery bypass surgery (MIDCAB) has recently been developed to reduce surgical invasiveness for single LAD revascularization. This study focus on the question whether MIDCAB could be an alternative treatment for isolated proximal LAD lesions. METHODS: Starting in 1996, MIDCAB was performed in 618 patients. Angiography was performed before discharge and repeated after 6 months at follow-up examination. In an ongoing randomized trial 150 patients with an indication for treatment of a LAD lesion have been included to compare the mid-term outcome after PTCA (n=79) vs. MIDCAB (n=71). RESULTS: In 618 MIDCAB procedures 30-day mortality was 0.6%, perioperative myocardial infarction rate was 1.6%. The conversion rate to sternotomy was 3.4%. The learning curve was demonstrated by a patency rate of 96.0% in 1997, 98.0% in 1998 and 99.1% in 1999, respectively. At 6 months patency rate was 94.4% in 1997 and 97.0% in 1998. The rate of severe stenosis >75% dropped from 5.4% in 1997 to 3.4% in 1998. The over all rate of reinterventions was 5.6%. The preliminary result of the randomized trial revealed a difference in the number of perioperative adverse events, 11.4% in the MIDCAB group vs. 6.3% in the PTCA group (P<0.05). At 6 months follow-up 88. 7% of the MIDCAB patients were free from angina vs. 58.2% of the PTCA patients (P<0.02). Restenosis and a positive stress test was diagnosed in 27.9% of the PTCA patients vs. 8.4% of the MIDCAB patients (P<0.02). Reintervention was necessary in 27.9% of the patients after PTCA vs. 8.4% of the patients after MIDCAB. CONCLUSION: MIDCAB is a safe and effective but technically demanding procedure. Perioperative adverse events may be expected, but early as well as mid-term patency rate are good. When compared to PTCA, the freedom from angina and the need for additional revascularization procedures after 6 months is statistically better for patients having MIDCAB surgery. Thus, MIDCAB is considered a valuable alternative for isolated proximal high grade LAD lesions.

Adult↗

PubMed2000

Endothelial function of human vena saphena magna prepared with different minimally invasive harvesting techniques.

OBJECTIVES: Minimally invasive saphenous harvesting techniques have been shown to reduce post-operative morbidity. However, when applying new techniques of vein harvesting, endothelial integrity should be preserved in order to guarantee graft quality. We investigated the impact of two different minimally invasive saphenous vein harvesting techniques on endothelial function compared with the traditional 'open' technique by inducing endothelium-dependent in vitro relaxation. METHODS: Two different minimally invasive techniques for harvesting the greater saphenous vein were used in 66 patients, either using a video-assisted dissector (ETHI, n=33) or a light coupled retractor (AUTS, n=33); other patients were treated conventionally (CONV, n=30). The physiological response was tested in vitro using an organ chamber on vein segments exposed to acetylcholine after precontraction with potassium. RESULTS: In both minimally invasive groups, two patients each had to be converted to the traditional open technique and dropped out of the study. The endothelial function of the other veins harvested by either of the minimally invasive techniques showed no significant difference compared with veins harvested conventionally. Reactivity was measured as the percentage relaxation of pharmacological contraction and was significant in all groups (P<0.05); ETHI, 49.1+/-4.2%; AUTS, 48.8+/-5.1%; and CONV, 51.7+/-6. 0%. The responder/non-responder ratio was similar in all groups: ETHI (two drop-outs), 28/3 (90.3%); AUTS (two drop-outs), 28/3 (90. 3%); and CONV, 27/3 (90.0%). CONCLUSION: Veins harvested by minimally invasive techniques have not shown an impaired reactivity of the endothelium compared with the conventional technique.

Endothelium, Vascular↗

PubMed2000

Total endoscopic computer enhanced coronary artery bypass grafting.

OBJECTIVE: In an effort to minimize access in coronary artery bypass (CAB) surgery, a total endoscopic approach using computer enhanced technology was developed. METHODS: By July 1999 the da Vinci telemanipulation system (Intuitive Surgical, Mountain View, CA) was used in 66 patients with coronary artery disease. In 12 patients undergoing routine coronary artery bypass grafting (CABG) (group 1) the internal thoracic artery (ITA) to left anterior descending artery (LAD) anastomosis was performed remotely using the system. In 32 patients (group 2) endoscopic dissection of the ITA was performed followed by a conventional minimally invasive direct coronary artery bypass (MIDCAB) operation. In 22 patients (group 3) the complete operation was performed endoscopically through 4 ports (total endoscopic coronary artery bypass, TECAB). Port-Access cardiopulmonary bypass with cardioplegic arrest was used for TECAB. RESULTS: In group 1 the time for performing the ITA to LAD anastomosis was 17 +/- 10 min. Mean graft flow was 38 +/- 25 ml/min. One anastomosis leaked and was repaired manually. In group 2 in 31/32 patients (96%) the ITA harvest was successfully performed with the system at mean of 61 +/- 27 min. There was a substantial learning curve associated with ITA take-down. In one patient a dissection caused insufficient free ITA graft flow which necessated additional vein grafting. Postoperative angiography demonstrated graft patency in all cases. In the TECAB group, the operation could be completed through four ports in 18 of the 22 patients (82%) with operating times in the range 220-507 min. In four patients, elective conversion to a minithoracotomy was required due to failure to identify the LAD (1), bleeding from the anastomosis (1), grafting of a diagonal branch (1) and torsion of the pedicle (1). One patient required reoperation for bleeding from an ITA side-branch. Median intubation time was 13 h and stay on ICU and hospitalization were 20 h and 7 days, respectively. A 3-month follow-up angiography revealed patent grafts in all TECAB patients. CONCLUSION: Endoscopic ITA harvesting and performing of arterial anastomoses can be safely performed with the da Vinci system. TECAB is possible on the arrested heart with good functional results. However, a substantial learning curve has to be overcome which is reflected in long operation times and an initial significant conversion rate.

Cardiopulmonary Bypass↗

PubMed2000

Comparison of On-X and SJM HP bileaflet aortic valves.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the hemodynamic function after aortic valve replacement (AVR) using the On-X valve, in comparison with St. Jude Medical (SJM) HP bileaflet valves. METHODS: Patients received either the On-X (n = 20) or SJM HP prosthesis (n = 20) for AVR. The control (SJM HP) group was computer-matched with the On-X group for age, gender, aortic stenosis as underlying disease, body surface area, NYHA functional class, left ventricular size, mass and function, transvalvular pressure gradients and cardiac index. Mean implanted valve size was 23.5 mm (three 21 mm, ten 23 mm, six 25 mm, one 27 mm) in both groups. All patients underwent postoperative, and six- and 12-month follow up echocardiography. RESULTS: The intra- and postoperative course was uneventful in all patients. There were no significant differences in cross-clamp and cardiopulmonary bypass times, intensive care unit stay, in-hospital stay and postoperative NYHA functional class. Two patients (both On-X) had paravalvular leakage postoperatively and at follow up. Five patients in the control group had additional myocardial revascularization. Transvalvular flow velocities were 2.38 +/- 0.3 versus 2.38 +/- 0.4 m/s (p = NS) postoperatively, and 2.08 +/- 0.2 versus 2.22 +/- 0.3 m/s (p = NS) at one year follow up for On-X and SJM HP valves, respectively. Maximum pressure gradients were 16.9 +/- 6.0 versus 18.5 +/- 8.0 mmHg (p = NS) postoperatively and 14.0 +/- 3.7 versus 16.5 +/- 5.7 mmHg (p = NS) at one year for the two valve types, respectively. A relatively pronounced transvalvular reflux was diagnosed for On-X valves. CONCLUSION: At one year after implantation, the On-X bileaflet prosthesis is equally suited for AVR in comparison with the 'standard' therapy (SJM HP). Exact sizing requires some experience. There were no significant differences between the two prostheses with regard to hemodynamic parameters either postoperatively or at one-year follow up. Long-term prospective randomized studies yet have to be carried out.

Aortic Valve↗

PubMed2000

Total endoscopic off-pump coronary artery bypass grafting.

Two cases of totally endoscopic off-pump coronary artery bypass grafting (TECAB) of the left internal thoracic artery to the left anterior descending artery using the da Vincitrade mark telemanipulation system (Intuitive Surgical, Mountain View, CA) are described. A new articulating endoscopic stabilizer with cleats was developed to enable endoscopic anchoring of silastic vessel loops for vascular occlusion. Newly created attachments for irrigation and suction, along with active robotic enhanced assistance by a second surgical console, permitted our group to perform for the first time a truly endoscopic bypass grafting without any thoracotomy.

Coronary Artery Bypass↗

PubMed2000

Functional and morphologic assessment of saphenous veins harvested with minimally invasive techniques using a modified laryngoscope.

BACKGROUND: Minimally invasive saphenous vein harvesting techniques have been shown to reduce postoperative morbidity. Commercially available and often disposable instruments add significant costs to the operation. To lower expenses and to reduce postoperative morbidity, we used an ordinary laryngoscope fitted with a modified # 3 Heine blade for harvesting the greater saphenous vein for coronary artery bypass surgery. OBJECTIVE: To assess the integrity and function of the autologous, undistended, long saphenous vein harvested by a modified laryngoscope. METHODS: Morphology was examined by light and scanning electron microscopy. Endothelial function was assessed by vascular reactivity in an isolated organ bath. Veins, randomly taken and prepared traditionally, served as a control group. Contractile function was measured in response to potassium chloride. Endothelium-dependent relaxation was assessed by use of acetylcholine and calculated as percentage relaxation. RESULTS: There were no significant differences, in response to the constricting or dilating agent, in vein rings taken with the modified laryngoscope compared with the traditional 'open' technique (n = 10, p > 0.05 by ANOVA). Histologic examination by light and scanning electron microscopy showed no significant damage to the endothelial layer. CONCLUSION: Minimally invasive saphenous vein harvesting, using a modified laryngoscope yields morphologically and biologically intact veins.

Analysis of Variance↗

PubMed2000

[Robotic-guided techniques in heart surgery].

The rigid design of conventional endoscopic instruments with limited degrees of freedom has not allowed for endoscopic cardiac surgery. Using a surgical telemanipulation system that is operated from a master console, endoscopic coronary artery bypass grafting and mitral valve repair can be performed with high precision. Closed-chest cardiopulmonary bypass systems that allow cardioplegic cardiac arrest are required. After extensive experimental testing a telemanipulation system was used clinically.

Cardiac Surgical Procedures↗

PubMed2000

Papillary fibroelastoma of the aortic valve with temporary occlusion of the left coronary ostium.

We report a rare tumor of the aortic valve located at the commissure close to the left coronary ostium in a 71-year old female patient. Due to an intermittent obstruction of the left coronary ostium, the patient became symptomatic and presented with repeated angina and syncope. Diagnosis was made by echocardiography and confirmed by surgery. Complete surgical removal of the tumor was possible, without replacement of the aortic valve. Histology revealed the diagnosis of a papillary fibroelastoma.

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