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Oliver Reuthebuch

Publications and source records attributed to Oliver Reuthebuch.

9 recordsLinked to original sources
PubMed2005

Guidant Heartstring: initial experience in OPCAB surgery.

PURPOSE: The aim of this study was to evaluate the feasibility of the Heartstring hemostatic seal system for proximal anastomoses without the need for aortic side clamping in off-pump coronary artery bypass surgery . MATERIAL AND METHODS: Between May and November 2003, 50 proximal bypass anastomoses were performed with the Heartstring device in 29 consecutive patients (21 men, 8 women) with calcified aorta (assessed by transesophageal echocardiography/digital palpation). Mean patient age was 68 +/- 7 years. A mean of 1.7 anastomoses per patient was performed. Bypass patency was assessed by intraoperative flow measurements. Neurological outcome was graded in 4 severities. RESULTS: The learning curve was completed after deployment of approximately 10 devices. Crack of the seal prior to deployment occurred in 8 cases. No conversion to conventional side clamping was needed. No accidental stitching of the seal or wrapping of the suture around the seal stem occurred. Slight diffuse bleeding occurred with arterial pressure under 65 mm Hg. Bypass graft flow was 53.7 +/- 23.9 L/min. No perioperative ischemic events occurred, and there were no postoperative neurological complications. CONCLUSIONS: Proximal bypass aortic anastomoses can be performed safely without side clamping using the Heartstring hemostatic seal system. Anastomoses can be completed with no foreign material (stent) remaining.

Aged↗
PubMed2004

Advantages of subclavian artery perfusion for repair of acute type A dissection.

OBJECTIVE: Arterial perfusion through the right subclavian artery is proposed to avoid intraoperative malperfusion during repair of acute type A dissection. This study evaluated the clinical and neurological outcome of patients undergoing surgery of acute aortic type A dissection following subclavian arterial cannulation compared to femoral artery approach. METHODS: From 1/97 to 1/03, 122 consecutive patients underwent surgery for acute type A aortic dissection. Subclavian cannulation was performed in 62 versus femoral cannulation in 60 patients. Clinical characteristics in both groups were similar. Mean age was 61 years (SD+/-14 years, 72% male) and mean follow-up was 3 years (+/-2 years). Patient outcome was assessed as the prevalence of clinical complications, especially neurological deficits, mortality at 30 days, perioperative morbidity and time of body temperature cooling and analyzed by nominal logistic regression analysis for odds ratio calculation. RESULTS: Arterial subclavian cannulation was successfully performed without any occurrence of malperfusion in all cases. Patients undergoing subclavian cannulation showed an odds ratio of 1.98 (95% CI 1.15-3.51; P=0.0057) for an improved neurological outcome compared to patients undergoing femoral cannulation. Re-exploration rate for postoperative bleeding was significantly reduced in the subclavian group (P<0.0001), as well as occurrence of myocardial infarction (P<0.0001) and duration for body temperature cooling (P=0.004). The 30-day mortality of patients with femoral cannulation was significantly higher compared to patients with subclavian artery cannulation (24 versus 8%; P=0.0179). CONCLUSIONS: Arterial perfusion through the right subclavian artery provides an excellent approach for repair of acute type A dissection with optimized arterial perfusion body perfusion and allows for antegrade cerebral perfusion during circulatory arrest. The technique is safe and results in a significantly improved clinical and especially neurological outcome.

Adult↗
PubMed2004

Early bypass occlusion after deployment of nitinol connector devices.

BACKGROUND: Reducing the negative side effects associated with extracorporeal circulation is the major advantage of off-pump revascularization. However, side clamping of a calcified aorta for proximal anastomoses can cause emboli, resulting in neurologic damage. This problem has been addressed by introducing a mechanical anastomosis device (Symmetry, St Jude Medical) that allows vein-to-aorta anastomosis without manipulating the aorta. This report describes our experience with this device. METHODS: Between June 2001 and April 2002, 77 connectors (1.3 per patient) were deployed in 61 patients (51 men and 10 women; mean age, 68 +/- 8.6 years) undergoing off-pump coronary artery bypass grafting or beating-heart revascularization. Intraoperative quality assessment included transit-time flow measurement (Medistim) and indocyanine green-based angiography (Spy, Novadaq). RESULTS: The surgeons were meticulously trained in loading of the device. No postoperative neurologic deficits were detected. Fifty-three patients had an uneventful course. However, 8 (13.1%) patients with 12 implanted connectors were symptomatic within 8 months (1 day to 8 months). Angiography revealed significant (95%) stenosis or even occlusion of the proximal vein-to-aorta anastomosis at the level of all connectors. Four patients underwent reoperation (2 dilated-stented and 2 treated with drugs). CONCLUSION: On the basis of these observations, the routine use of the connector was halted at our institution. At the moment, the use of this therapy is reserved for patients with severely calcified aortas with no technical alternative. Further investigations appear necessary to evaluate the clinical patterns of this otherwise promising technology.

Aged↗
PubMed2004

Novadaq SPY: intraoperative quality assessment in off-pump coronary artery bypass grafting.

OBJECTIVES: Off-pump coronary artery bypass grafting may decrease operative morbidity when compared to on-pump bypass grafting; however, it is technically demanding and thus quality control is essential. This study assesses the clinical feasibility of a new, indocyanine green (ICG)-based imaging system (SPY; Novadaq Technologies; Toronto, ON, Canada) to monitor the quality of anastomoses and grafts in off-pump revascularization. SETTING: Thirty-eight consecutive patients undergoing nonemergent coronary artery bypass grafting without the use of extracorporeal circulation at two Swiss cardiac surgery clinics were included. On completion of bypass grafts, the quality of the grafts was assessed using the ICG-based imaging system. The imaging device comprises an 806-nm laser light source that is used to cause ICG to fluoresce and a near infrared-sensitive charged couple device videocamera that is used to capture the fluorescence images. ICG was administered through the central venous line, and images were acquired during the first pass of the ICG through the field of view. Graft flow (qualitative) and the quality of the grafts and anastomoses were assessed intraoperatively. RESULTS: Between March 2002 and September 2002, a total of 38 patients (26 men and 12 women; mean +/- SD age, 64.6 +/- 10.5 years; body mass index, 27.1 +/- 2.9) underwent surgery and imaging at two institutions. One hundred seven of 124 grafts (45 arteries and 62 veins) were analyzed. Seventeen grafts could not be assessed due to difficulties in positioning. The imaging system was easy to handle, and no adverse reactions to ICG were observed. Four of the 107 grafts imaged required revision (three anastomotic constrictions and one graft dissection). Each imaging sequence required approximately 1.25 to 2.5 mg of ICG. The images were equivalent to angiography without the need for radiographs and catheter insertion. In addition, the course of coronaries that would otherwise be difficult to locate in obese patients could be detected using the imaging system. Biochemical and ECG data demonstrated an absence of intraoperative or postoperative myocardial damage, and no liver enzyme elevation or renal dysfunction. CONCLUSIONS: This study supports the clinical utility of a ICG-based imaging system for the assessment of the quality of bypass grafts, which appears to be safe and simple to use.

Aged↗
PubMed2004

The CentriMag: a new optimized centrifugal blood pump with levitating impeller.

PURPOSE: Blood pumps are routinely used for circulatory and pulmonary support. However, blood trauma and pump failure remain severe drawbacks of currently available pump models. This study evaluated the first clinical application of a new, totally bearingless centrifugal blood pump (CentriMag). MATERIAL AND METHODS: A centrifugal pump consisting of an electromagnetic suspended impeller was used as a blood pump during beating-heart coronary artery bypass grafting in 11 patients (mean weight, 77.4 kg). Heparin in a bolus of 150 IU/kg body weight was administered, and activated clotting time was maintained at approximately 180 to 250 seconds during extracorporeal circulation. Pump-induced blood trauma was evaluated by measurement of plasma free hemoglobin (PFH), lactate dehydrogenase (LDH), hematocrit, total bilirubin, and platelet levels. RESULTS: Mean pump flow was 3.3 +/- 0.62 L/min, and mean pressure gradient through the oxygenator was 69 +/- 4 mm Hg. No pump dysfunction occurred during a mean application time of 105 +/- 26 minutes. Inspection of the pump housings showed no internal thrombus formation despite low-dose heparinization. Only slight hemolysis was observed with a mean PFH level of 1.96 micromol/L; LDH, 460 U/L; hematocrit, 33%; total bilirubin, 25 micromol/L; and platelets, 191 x 10(3)/microL. CONCLUSIONS: The bearingless CentriMag blood pump is a safe and reliable new device that produces only minimal hemolysis. It seems to be suited for long-term evaluation as a blood pump for extracorporeal membrane oxygenation or as ventricular assist device.

Aged↗
PubMed2004

Surgical treatment of infective mitral valve endocarditis.

BACKGROUND AND AIM OF THE STUDY: The approach to mitral valve endocarditis is a surgical challenge, and the optimal procedure remains a matter of debate. In this condition, mitral valve repair appears feasible, but its long-term effects--as opposed to more often practiced valve replacement--have not yet been determined. Herein, the authors' experience of surgical treatment of infective mitral valve endocarditis is presented, with reference to surgical replacement or reconstruction. METHODS: A retrospective analysis was performed of all patients with infective native mitral valve endocarditis treated surgically at the University Hospital Zurich and the City Hospital Triemli Zurich between 1980 and 1996. Of 154 patients, 97 (63%) underwent mitral valve replacement, and 57 (37%) mitral valve reconstruction. RESULTS: The 30-day mortality was 3.2% (5/154); 4% (4/97) after replacement and 1.7% (1/57) after reconstruction (p = 0.67). Survival (Kaplan-Meier) was 93%, 81% and 61% after one, five and 10 years, respectively. There was no significant difference between valve replacement and reconstruction in terms of long-term survival (p = 0.15), but there was a trend towards better survival after reconstruction than replacement if only cardiac deaths were considered (p = 0.1). At follow up, reconstruction patients were significantly less frequently symptomatic (NYHA class III/IV) than replacement patients (0% versus 29%; p = 0.002), had a lower incidence of atrial fibrillation and need for pacemaker implantation (29% versus 47%; p = 0.04), and tended to have less dyspnea in daily life (20% versus 38%; p = 0.07). Reoperation in patients surviving more than 30 days was more common in replacement than in reconstruction patients. CONCLUSION: The present data suggest a trend for better clinical outcome after mitral valve reconstruction than after replacement when treating mitral valve endocarditis. These results encourage mitral valve reconstruction in mitral valve endocarditis, but recommendations to clinicians undertaking surgery on mitral valve endocarditis must be made with caution.

Adolescent↗
PubMed2003

[Totally artificial training model for coronary heart surgery: the renunciation of animal experiments?].

AIM: Animal protection laws will lead to stricter and more selective criteria thus resulting in a decline of available animals. Yet to train cardiac surgical skills a totally artificial training model was developed. DESCRIPTION OF THE TRAINING MODEL: The model is based on differently hardened polyurethane. Cover is a 1:1 replica of the human thoracic wall. Disposable coronaries are integrated in the heart-model. Vessels and part of the ascending aorta can be rinsed. By means of a newly designed air-pump stroke volume, heart-rate and rhythm can be adjusted. EXPERIENCES: Set-up of the model is easy and quick. Accustomed instruments can be used. Handling of artificial tissue is nature-like. Degree of difficulty is dependent on stroke volume, heart rate, arrhythmia, vessel-size and vessel-quality. CONCLUSION: The phantom helps to achieve confidence in coronary revascularisation. It facilitates an accompanying training for the less-trained as well as the skilled surgeon. The nature-like characteristics will help to reduce animal experiments in future.

Animal Testing Alternatives↗
PubMed2003

A single bicaval venous cannula used for optimization of endoscopic robotically assisted procedures of the heart.

Robotically assisted heart operation is one of the minimally invasive approaches that have revolutionized many surgical procedures. Robotic procedures on the heart, however, are by no means routine, and their optimization requires development of new instruments and techniques. Described here is the robotically assisted use in a sheep model of a new peripherally inserted bicaval venous cannula in the totally endoscopic closure of atrial septal defect. The exposure of the surgical target area was successful with no obstructions in the surgical view. The cannula shows sufficient flow characteristics for cardiopulmonary bypass. Subsequent suturing of the atrial septum defect was achieved without complications in the 4 experimental animals.

Animals↗