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Andrzej W Sosnowski

Publications and source records attributed to Andrzej W Sosnowski.

9 recordsLinked to original sources

Tube-graft inversion for the construction of an "open" distal anastomosis during ascending aortic replacement: a new technique.

For the construction of a distal "open" anastomosis during ascending aortic replacement, a tube-graft is placed opposite to the transected aorta. We describe an alternative technique. The tube-graft is inverted and positioned within the aortic arch in a way that brings the entire circumference of the distal end of the tube-graft next to the circumference of the transected aorta. An end-to-end anastomosis is then fashioned with a running suture, the needle of which goes through the aorta and the tube-graft in a single pass. This technique permits easy, accurate, and fast suture placement, producing a hemostatic distal anastomosis within a short circulatory arrest time.

Anastomosis, Surgical↗

Edge-to-edge repair with mitral annuloplasty for Barlow's disease.

BACKGROUND: The purpose of this study was to define the early and midterm results obtained after the use of edge-to-edge repair with mitral annuloplasty in the setting of Barlow's disease. METHODS: Between 1998 and 2004, 41 patients having Barlow's disease had an edge-to-edge repair creating a double-lumen mitral valve orifice in our unit. In 38 patients (93%), an annuloplasty band was also inserted. RESULTS: Preoperatively, all patients had severe mitral regurgitation (MR), 12 were in New York Heart Association (NYHA) class I, 15 in class II, and 14 in class III. One patient died in hospital (2.4%) and 5 experienced complications (12.5%). There were no late deaths. At follow-up, 2 patients had severe MR and underwent valve replacement, 1 exhibited moderate MR, and 5 had mild MR. Kaplan-Meier 5-year survival, freedom from reoperation and recurrent moderate-severe MR was 97.6% +/- 2.4%, 94% +/- 4.4%, and 90.6% +/- 5.1%, respectively. At latest echocardiographic evaluation (mean 35 +/- 12 months) the mean left ventricular end-systolic and end-diastolic diameters, and the mitral valve area decreased (p = 0.0001) compared with baseline. The mean mitral valve gradient increased (p = 0.001) without clinical evidence of mitral stenosis whereas ejection fraction did not change. Currently, 35 patients are in NYHA class I and 5 are in class II. CONCLUSIONS: In the setting of Barlow's disease, use of edge-to-edge repair with mitral annuloplasty is safe and provides lasting restoration of mitral valve competence with measurable hemodynamic and clinical benefits. In our unit, it is the procedure of choice for correction of MR in patients having Barlow's disease.

Aged↗

Performance of polymethyl pentene oxygenators for neonatal extracorporeal membrane oxygenation: a comparison with silicone membrane oxygenators.

OBJECTIVE: To review the performance of polymethyl pentene versus silicone oxygenators in terms of efficiency in priming and oxygenation, oxygenator resistance, requirements for coagulation proteins and consumption of blood products, for neonatal extracorporeal membrane oxygenation (ECMO) patients. STUDY DESIGN: Forty consecutive neonates were selected retrospectively pre- and post-introduction of the new polymethyl pentene (PMP) oxygenators. They formed two equal groups. After calculation of the sample size, data were collected from ELSO registry forms and patient records. Results were analysed using parametric and non-parametric tests. RESULTS: Neonatal PMP (N-PMP) oxygenators were smaller, faster and easier to prime. They were less efficient than silicone oxygenators, especially in carbon dioxide elimination, and, therefore, required higher sweeps. The preservation of coagulation proteins was significantly better, but there was no reduction in the consumption of blood products, despite having less than half the surface area and significantly lower blood path resistance. CONCLUSION: Small PMP oxygenators (Medos Hilite 800 LT) provide adequate gas exchange and offer technical advantages in terms of more efficient priming, reduced haemodynamic resistance and better control and preservation of coagulation proteins than silicone oxygenators.

Equipment Design↗

A potential propensity for failure secondary to clot embolism in neonatal ECMO.

OBJECTIVE: To report a single case of oxygenator failure caused by clot embolism originating from the bladder; and to discuss some preventative options. CASE REPORT: A 2.5 kg neonate with a diagnosis of influenza A received veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) for cardiorespiratory support. Halfway through treatment, she underwent an elective circuit change for numerous clots in her circuit. The patient continued to consume vast quantities of platelets and developed a fatal oxygenator failure after 18 days. DISCUSSION: Amongst the factors influencing the outcome in events of a sudden unexpected oxygenator failure are the severity of patient illness, the size of the clot relative to the size of the oxygenator, the availability of a previously primed circuit and the ease and speed of priming a new oxygenator. CONCLUSION: There is a need for improvement in the design of small oxygenators and ECMO circuits. Adjustment of the coagulation parameters and lowering the tolerance towards clots in the circuit by electively changing them may reduce the incidence of sudden unexpected oxygenator failure. However, using a slightly larger Medos oxygenator may gain valuable time needed to arrange an oxygenator/circuit change.

Equipment Design↗

Use of stentless xenografts in the aortic position: determinants of early and late outcome.

BACKGROUND: Whether to perform a stentless aortic valve replacement (AVR) is not well established. Our aim was to determine the outcome after AVR with stentless xenograft valves. METHODS: Between 1996 and 2001, a total of 404 patients (mean age 70.4 years) underwent a stentless AVR by one surgeon in our unit. Concomitant procedures were performed in 132 patients (33%). Twenty patients (6.4%) had undergone previous AVR. Eleven types of stentless xenograft valves were implanted: Medtronic Freestyle in 221 patients (55%), Shelhigh in 55 (14%), Shelhigh composite conduit in 33 (8%), Sorin in 26 (6%), Cryolife O'Brien in 25 (6%), Aortech-Elan in 17 (4%), Edwards Prima in 14 (4%), Toronto SPV in 7 (2%), and other valves in 6 (1%). A subcoronary implantation technique was used in 302 cases (76%), complete root replacement in 62 (15%), and a modified Bentall-De Bono procedure in 33 (8%). Mean follow-up was 19.4 months (range, 1.2 to 60.6 months). RESULTS: Overall hospital mortality was 4.2%. This was 2.4% for isolated AVR, 3.6% for AVR and coronary artery bypass grafting, 5.5% for replacement of two or more valves, and 12% for the modified Bentall procedure. On multiple logistic regression redo cardiac operation (p = 0.0006), cardiogenic shock (p = 0.001), left ventricular ejection fraction less than 0.30 (p = 0.01), modified Bentall procedure (p = 0.03), and endocarditis (p = 0.04) were predictors of in-hospital death. Five-year freedom from thromboembolism, hemorrhage, prosthetic endocarditis, structural valve deterioration, and reoperation was 97%, 99%, 99%, 98%, and 96%, respectively. Kaplan-Meier survival at 5 years was 88%. On Cox regression, cardiogenic shock (p = 0.001) and older age (p = 0.03) were adverse predictors of survival. At echocardiographic examination within 6 months from the operation, mean aortic valve gradients were 15 +/- 6 mm Hg, 12.8 +/- 3 mm Hg, 10.8 +/- 4 mm Hg, 9.3 +/- 3 mm Hg, 9.1 +/- 4 mm Hg, and 8.2 +/- 3 mm Hg for valve sizes of 19, 21, 23, 25, 27, and 29 mm, respectively. CONCLUSIONS: The availability of several stentless valve designs facilitates the surgical treatment of diverse aortic valve or root diseases with encouraging early and mid-term results. Patients requiring concomitant procedures may also benefit from the excellent hemodynamic characteristics of a stentless valve. We consider stentless AVR the treatment of choice for patients older than 60 years and those having small aortic roots.

Adult↗

Poly-methyl pentene oxygenators have improved gas exchange capability and reduced transfusion requirements in adult extracorporeal membrane oxygenation.

The performance of poly-methyl pentene (PMP) oxygenators (Medos Hilite 7000LT) was compared with that of silicone membrane (SM) oxygenators (Medtronic 1-4500-2A) for adult extracorporeal membrane oxygenation (ECMO). Forty consecutive patients were selected retrospectively pre- and post-introduction of PMP oxygenators. They were selected according to the dates they received ECMO and were separated into two equal groups with similar backgrounds. The flow path resistance, gas and heat exchange efficiency, consumption of coagulation factors and platelets, blood transfusion requirements, and incidence of clots for each oxygenator type was assessed. Adult PMP oxygenators showed lower blood path resistance than SM oxygenators. However, lower consumption of blood products in these oxygenators was a direct result of their smaller surface area and heparin coated design, reducing contact activation of coagulation factors. These oxygenators are noticeably smaller, require lower priming volumes, and have better gas exchange capability than SM oxygenators. They showed greater stability and preservation of coagulation factors and platelets compared with SM oxygenators. They also had the advantage of a functioning integrated heat exchanger. Using a single PMP oxygenator in the first instance may be adequate for the majority of patients and would significantly reduce red blood cell consumption during ECMO.

Adult↗

Successful use of venovenous extracorporeal membrane oxygenation in accidental hypothermic cardiac arrest.

Cardiopulmonary bypass is usually used for rewarming and for providing cardiac support in patients with severe hypothermia and cardiovascular instability. We report the first case of accidental severe hypothermia associated with prolonged cardiac arrest that was successfully managed by venovenous extracorporeal membrane oxygenation.

Extracorporeal Membrane Oxygenation↗