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G J Van Nooten

Publications and source records attributed to G J Van Nooten.

10 recordsLinked to original sources
PubMed2001

Multicenter experience with the remote access perfusion (RAP) catheter.

BACKGROUND: Cardiac operation has rapidly evolved toward less invasive procedures. Total body perfusion from femoral or iliac vessels combined with endovascular aortic clamping can be achieved using the remote access perfusion (RAP) catheter without opening the sternum. The results of all reported RAP procedures were reviewed. METHODS: A US Food and Drug Administration/CE (Communaté Europeene) multicenter and postmark surveillance information survey from January 1999 to June 2000 evaluated 63 patients undergoing RAP procedures. The series includes coronary artery bypass grafting (46%), mitral valve operation (34%), and combined (3%) and miscellaneous procedures (17%). RESULTS: Since optimization of the catheter shape, easy placement was obtained during most procedures (74%). Only one procedure had to be converted to a standard approach. However, no dissection or perforation was reported. Perfusion yielded excellent flow characteristics of the RAP catheter predicted by in vitro studies. Continuous transesophageal echocardiography confirmed the stability of the endovascular balloon clamp (93%), most likely related to the near cylindrical balloon shape. In four cases an additional external cross-clamp was applied. The one reported hospital death (1.5%) was non-procedural related. No strokes were recorded. Peripheral vascular morbidity (8%) was higher during the early period but nearly disappeared after adaptation of the catheter shape. CONCLUSIONS: This multicenter study demonstrated the safety of the RAP technique. Excellent flow characteristics and balloon stability were obtained by improved technology. Indications will be extended in the future because of the device's enhanced safety and feasibility.

Aorta↗
PubMed1997

Pulse duplicator hydrodynamics of four different bileaflet valves in the mitral position.

The hydrodynamic performance of four different types of bileaflet heart valve was tested both in steady flow conditions and in a newly designed computerized artificial left heart system. Four 29-mm valves, manufactured by either St. Jude Medical, CarboMedics, ATS Medical or Medtronic Parallel were studied under a steady state and in pulsatile conditions by pressure and flow recording and colour Doppler echocardiography in the 'mitral position' at rest and at exercise (cardiac output range 4-30 l/Min). In the steady state, significant differences were measured at peak flows of 30 l/min, with mean (s.d.) increasing pressure drops (mmHg) recorded at 3.48(0.13) (St. Jude Medical), 3.80(0.11) (Medtronic Parallel), 4.31(0.06) (ATS Medical) (P < 0.005), and 4.78(0.06) (Carbo Medics), (P < 0.005). The mean ratio of the closing volume to the stroke volume was comparable for all valves despite one faulty sample. In the pulsatile state the effective orifice area calculated by the Continuity and Gorlin equations decreased from 2.10(0.04) (ATS Medical), 1.95(0.05) (St. Jude Medical), 1.87(0.03) (Carbo Medics) to 1.67(0.02) (Medtronic Parallel) independently of method used. No significant difference was found in the mean ratio of the regurgitant volume to the stroke volume. The performance index, defined as the ratio of effective orifice area to geometric orifice area ranks the valves in the order ATS Medical (0.44), St. Jude Medical (0.43), Carbo Medics (0.41) and Medtronic Parallel (0.38). Regurgitation visible on colour Doppler echo was a mere consequence of the working principle of the bileaflet valves in the mitral position and was by no means hydrodynamically important nor representative of severe insufficiencies. Differences between the valve types were notable under severe conditions, such as high peak flow.

Blood Pressure↗
PubMed1997

Hufnagel procedure reconverted by endovascular leaflet dislocation and extirpation.

Before the development of standard aortic valve replacement, Hufnagel treated aortic insufficiency by implanting a ball-valve prosthesis in the descending thoracic aorta. In a patient who, after four major thoracic procedures, ultimately received two mechanical bileaflet valves in series (one in the ascending and one in the descending aorta), the downstream prosthesis became progressively immobilized, with total blockage of the leaflets in the open position due to insufficient transvalvular negative pressure gradient. After evaluation of this particular situation in an experimental model, we predicted blockage of the downstream prosthesis, once the ascending valve had regained normal function, and easily cleared the blockage of the distal valve by removing the two leaflets using balloon inflation. Normal circulation was clinically restored in three separate steps. (a) Normal function was re-established surgically in the ascending aorta position. (b) A second thoracotomy was avoided by endovascular dislocation of both blocked descending thoracic leaflets through endovascular balloon inflation. (c) Both leaflets embolized to the level of the left common iliac artery, where the nearly intact leaflets were removed surgically, finally creating a near-normal circulatory situation.

Aorta, Thoracic↗
PubMed1995

Tricuspid valve replacement: postoperative and long-term results.

A series of 146 consecutive patients who underwent tricuspid valve replacement at the University Brugmann Hospital between 1967 and 1987 was reviewed. Mean age at operation was 51.4 years (+/- 12.1 years). Different types of prostheses were implanted including porcine and bovine pericardial bioprostheses and older and bileaflet mechanical valves. Most patients were severely disabled by their cardiac disease before operation, with 30.1% in New York Heart Association functional class III and 69.9% in class IV. Operative mortality and hospital mortality rates (30 days) were high (16.4%). Incremental risk factors for hospital death included icterus (p < 0.005), preoperative hepatomegaly (p = 0.012), and New York Heart Association functional class IV (p = 0.013). Multivariate analysis only selected preoperative icterus (p < 0.01) as being independently significantly related to hospital mortality. The hospital survivors were followed up for a median of 94 months. A complete follow-up was available for all patients except two for 30 months or more. At 30 months the only two significant parameters were the type of myocardial protection (p = 0.024) and the year of operation (before 1977 or after [precardioplegia era or after], p = 0.011). There were 70 late deaths during the entire follow-up period. The univariate (log-rank statistics) incremental risk factor for late death was the type of tricuspid prosthesis (Smeloff-Cutter and Kay-Shiley versus St. Jude Medical versus bioprosthesis) (p = 0.04). A trend was observed for the type of operative myocardial protection (normothermia and coronary perfusion) (p = 0.06) and preoperative New York Heart Association functional class IV (p = 0.055). Actuarial survival was 74% at 60 months and 23.4% at 180 months. Cumulative follow-up added up to 1015 patient-years. In a more detailed analysis of the effect on survival of the type of tricuspid prosthesis, a significant difference was observed between the bioprostheses and some older mechanical prostheses (Smeloff-Cutter and Kay-Shiley) (p = 0.04) but not between the bioprostheses and the bileaflet valves (p = 0.15). When the follow-up period was stratified according to less than 7 years and more than 7 years of follow-up, no difference was observed for the first period, but for the late follow-up the new mechanical prostheses did better than the bioprostheses (p = 0.05), suggesting a degradation of the bioprostheses after 7 years and favoring mechanical prostheses for those patients with a good long-term prognosis.

Actuarial Analysis↗
PubMed1995

The valve choice in tricuspid valve replacement: 25 years of experience.

This study reviews 146 consecutive patients who underwent tricuspid valve replacement (TVR) with 69 bioprostheses (porcine and bovine pericardial) and 77 mechanical ball, disc or bileaflet valves between 1967 and 1987. The mean age was 51.4 +/- 12.1 years. Preoperatively, 97% were in New York Heart Association (NYHA) functional class III or more and over 40% had undergone previous cardiac surgery. Hospital mortality was high (16.1%). Incremental risk factors for hospital death were preoperative icterus (P < 0.01), hepatomegaly (P = 0.02), NYHA functional class IV (P = 0.02) and male sex (P = 0.04) (univariate analysis). Ninety-eight percent of the hospital survivors were followed up for a mean of 92 months. Cumulative follow-up added up to 955 patient-years. There were 70 late deaths. The actuarial survival rate was 74% at 60 months and less than 25% at 14 years. Incremental risk factors for late death indicated by univariate analysis were the type of tricuspid prosthesis (Smel-off-Cutter and Kay-Shiley prostheses) (P = 0.04), the type of operative myocardial protection (normothermia and coronary perfusion) (P = 0.05) and preoperative NYHA functional class IV (P = 0.05). We conclude that TVR carries a high operative risk and poor long-term survival, both influenced by preoperative and perioperative variables. Bearing in mind the poor prognosis for TVR, we prefer a large-sized bioprosthesis, in view of its initial good durability and low risk of valve-related events. However, in patients with good life expectancy, a bileaflet mechanical prosthesis may be an acceptable alternative.

Actuarial Analysis↗
PubMed1994

Use of internal mammary artery for emergency grafting after failed coronary angioplasty.

Of 929 consecutive patients who underwent percutaneous transluminal coronary angioplasty over a 36-month period, 32 (3.4%) had emergency coronary artery bypass grafting for angioplasty failure. Twenty-two patients (69%) were hemodynamically stable (stable group), and 10 (31%) were unstable (unstable group) before emergency bypass. In the unstable group, the interval between failed angioplasty and opening of the grafts or end of extracorporeal circulation was significantly shorter (p < 0.001 and p < 0.002, respectively) and significantly more grafts per patient were performed (p < 0.05) than in the stable group. Twenty-seven patients (84%) received at least one internal mammary artery graft, independent of their hemodynamic condition. In 11 culprit left anterior descending arteries, the internal mammary artery graft was supplemented by a saphenous vein graft to the same territory, especially in the unstable group. There were no hospital deaths. Postoperatively, the incidence of myocardial infarction (p < 0.005) and the use of antiarrhythmics (p < 0.0001) were increased and length of stay tended to be longer in the unstable compared with the stable group. The use of a reperfusion catheter had no influence on clinical outcome, except for a significantly reduced postoperative use of antiarrhythmics (p < 0.05). The internal mammary artery can be used in emergency coronary artery bypass grafting after failed percutaneous transluminal coronary angioplasty, without hospital mortality and with acceptable morbidity, especially in hemodynamically stable patients.

Adult↗
PubMed1993

Anomalous origin of the left coronary artery from the pulmonary artery.

A 20-year-old woman underwent successful operative correction of anomalous origin of the left coronary artery from the pulmonary artery by left internal mammary artery bypass graft. The clinical, hemodynamic, and angiographic features of this unusual case are presented. Different therapeutic options are discussed.

Adult↗
PubMed1992

Heart transplantation after emergency coronary artery bypass for failed angioplasty.

We describe the case of a 48-year-old woman who required emergency coronary artery bypass grafting because of extensive dissection, cardiogenic shock, and ventricular fibrillation after failed percutaneous transluminal coronary angioplasty for stenosis of a proximal left anterior descending coronary artery. Despite maximal inotropic support and intra-aortic balloon pumping, the patient could not be weaned from cardiopulmonary bypass, and a left ventricular assist device was placed. After 2 days of postoperative circulatory support, during which her respiratory and renal functions declined and cardiac output remained negligible due to a massive myocardial infarction, she underwent successful orthotopic heart transplantation.

Journal Article↗