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Clark J Zeebregts

Publications and source records attributed to Clark J Zeebregts.

At least 19 recordsLinked to original sources

Is emergency endovascular aneurysm repair associated with higher secondary intervention risk at mid-term follow-up?

OBJECTIVE: The study assessed mid-term outcome of emergency endovascular repair for acute infrarenal abdominal aortic aneurysms, with special attention to secondary interventions. METHODS: Between May 1998 and August 2005, 56 patients underwent emergent endovascular repair for a ruptured abdominal aortic aneurysm (n = 34) or an acute nonruptured abdominal aortic aneurysm (n = 22). During the same period, 322 consecutive patients underwent elective endovascular aneurysm repair and were used as control group. Five types of stent grafts were used: Vanguard, Talent, Excluder, Zenith, and Quantum. Follow-up included abdominal radiograph, duplex ultrasound scanning, and computed tomographic angiography. Outcome measures included all-cause and aneurysm-related mortality, complications, and secondary interventions. RESULTS: Mortality at 30 days was 18%, 5%, and 1% in the ruptured, acute nonruptured, and elective aneurysm groups, respectively. Overall mean follow-up was 38 +/- 26 months. In the ruptured aneurysm group, survival was 67.8% +/- 8.6% at 1 year and 62.1% +/- 9.5% at 2 and 3 years. Seven secondary interventions (4 early and 3 late) were required in five patients (15%), with a cumulative risk of 9.2% +/- 5.1% at 1 year and 16.2% +/- 8.2% at 2 and 3 years. In the acute nonruptured aneurysm group, survival was 90.9% +/- 6.1% at 1 year, 84.8% +/- 8.2% at 2 years, and 76.4% +/- 10.9% at 3 years. Four secondary interventions (1 early and 3 late) were required in four patients (18%), with a cumulative risk of 9.6% +/- 6.5% at 1 and 2 years and 20.9% +/- 12.0% at 3 years. In the elective aneurysm (control) group, survival was 95.2% +/- 1.2% at 1 year, 89.9% +/- 1.8% at 2 years, and 86.2% +/- 2.1% at 3 years. A total of 51 secondary interventions (4 early, 47 late) were required in 38 patients (12%), with a cumulative risk of 4.2% +/- 1.1% at 1 year, 7.6% +/- 1.6% at 2 years, and 12.9% +/- 2.2% at 3 years. CONCLUSIONS: To our surprise, emergency endovascular aneurysm repair did not present with higher secondary intervention rate at mid-term follow-up.

Angioplasty↗

Endovascular treatment of iliac artery aneurysms with a tubular stent-graft: mid-term results.

OBJECTIVE: To report the mid term results of a prospective cohort of iliac artery aneurysms (IAAs) treated with endovascular tubular stent-grafts. METHODS: All IAAs referred to the University Medical Center Groningen between June 1998 and June 2005 were evaluated for endovascular repair. Criteria for repair were a diameter of > or = 30 mm for anastomotic aneurysms and > or = 35 mm for true aneurysms. Preferentially, tubular grafts were used. Follow-up included both radiographs of the abdomen and duplex examination. RESULTS: In 35 patients, 40 IAAs were treated endovascularly with a tubular stent-graft. Elective repair was performed in 30 patients (86%) and emergent repair in five patients (14%). Aneurysms were false in 26 cases (65%) and true in 14 cases (35%). Local anesthesia was used in 74% of the cases. The stent-grafts that were used included the Excluder contralateral limb (n = 28, 70%), Passager (n = 9, 22.5%), Hemobahn (n = 2, 5%), and Wallgraft (n = 1, 2.5%). The mean operation time was 83 +/- 28 minutes (range, 50 to 150 minutes). Mean hospital stay was 3.3 +/- 2.3 days (range, 1 to 12 days). There was no 30-day mortality. Patients were followed up for a mean of 31.2 +/- 20.7 months (range, 3 to 83 months). Complications occurred in two patients during follow-up, including migration with a proximal type I endoleak in one, and occlusion of the stent-graft in the other. The internal iliac artery was intentionally sacrificed in 28 patients (70%), and this led to gluteal claudication in three patients. CONCLUSION: Endovascular repair of iliac artery aneurysms with flexible stent-grafts is a minimally invasive technique and is associated with low mortality and morbidity. Follow-up results up to 5 years suggest that the technique is durable. It should be regarded as a first choice treatment option for suitable aneurysms.

Aged↗

Mid-term results of endovascular aneurysm repair with branched and fenestrated endografts.

PURPOSE: The technique of fenestrated and branched endovascular aneurysm repair (EVAR) has been used for the treatment a variety of aortic aneurysms. Although technically successful, longer-term results have been lacking. This article reports on the mid-term results of aneurysm repair with fenestrated and branched endografts from a European center with a large endovascular experience. METHODS: Between 2001 and 2005, 38 patients were prospectively enrolled in a single institution, investigational device protocol database. Indications for fenestrated or branched EVAR included unfavorable anatomy for traditional EVAR and an abdominal aortic aneurysm >5.5 cm in maximum diameter. Customized stent-grafts were either fenestrated or branched and based on the Zenith system. Data were analyzed on an intention-to-treat basis. Differences between groups were determined using analysis of variance with P < .05 considered significant. RESULTS: The mean (SD) follow-up was 25.8 +/- 12.7 months (median, 25.0 months; range, 9 to 46 months), and no patients were lost to follow-up. All cause mortality was 13% (5/38), with all deaths occurring within the first postoperative year; 30-day mortality was 2.6%. No patient died during the operation. Completion angiography demonstrated successful sealing in 37 of 38 patients and an overall operative visceral vessel perfusion rate of 94% (82/87). Cumulative visceral branch patency was 92% at 46 months. Stent occlusions, when they did occur, all happened within the first postoperative year. All postoperative occlusions occurred in unstented fenestrations or scallops. No occlusions occurred in stented vessels. The difference in serum creatinine preoperatively and postoperatively at 6 months, 1, 2, and 3 years was not significant (P = NS). No patient required dialysis. The aneurysm sac size decreased significantly during the first year and then remained stable (P < .05). Limb perfusion as assessed by the ankle/brachial index was not affected by the presence of a fenestrated or branched endograft. CONCLUSIONS: The intermediate-term results of fenestrated and branched endografts support their continued use in patients with anatomic contraindications for standard EVAR. Close surveillance is mandatory for early identification of visceral or branched vessel stenosis and preocclusion. All cases of failure appear to occur during the first year and then level off in subsequent longer-term follow-up. This includes death, secondary interventions, branch vessel patency, and complications. As the procedure matures, long-term results and randomized clinical trials will ultimately be required to determine the safety, efficacy, and stability of this system.

Aortic Aneurysm, Abdominal↗

Within-session and between-session variability of haemodialysis shunt flow measurements.

BACKGROUND: Knowledge of the variability of a measurement method is essential for its clinical application. We investigated the variability of shunt flow measurements, since this is a relatively neglected area in the literature. In particular, no direct comparison of between-session and within-session variability was available until now. METHODS: During two consecutive dialysis sessions, shunt flow was measured three times with the ultrasound dilution method in 24 chronic haemodialysis patients with various types of shunts. Needle orientation and blood pressure at the time of flow measurement were recorded. In these patients, shunt flow was also measured three times by duplex ultrasound before the first dialysis session. RESULTS: The within-session variation coefficient (VC) of shunt flow measured with ultrasound dilution was 7.7%, whereas the between-session VC was 14.2% (n.s.). The within-session VC of Doppler shunt flow was 11.6% which was not significantly different from the corresponding figure of ultrasound dilution. Analysis of subgroups showed that changes in needle orientation caused large differences between sessions in radiocephalic fistulas but not in brachiocephalic fistulas: in the radiocephalic fistulas with the same needle orientation, VC was 6.7%, but with different needle orientation it was 23.5% (P = 0.02); the corresponding figures for brachiocephalic fistulas were 14.6% (same direction) and 11.4% (different direction, n.s.). CONCLUSION: Reproducibility of shunt flow measurements between dialysis sessions in radiocephalic fistulas is critically dependent on similar needle orientation. With similar needle position and correction for blood pressure differences, flow changes of more than 20-25% are likely to reflect true flow changes. The variability of duplex flow measurements is at least as large as that of the ultrasound dilution method.

Adolescent↗

Anterior resection of rectal cancer without bowel preparation and diverting stoma.

PURPOSE: Since the introduction of total mesorectal excision (TME) as the standard operation technique for rectal cancer, anastomotic leakage percentages of up to 18% have been reported. To prevent such leakage, the use of mechanical bowel preparation and also the construction of a diverting ileostoma or colostomy have been standard procedures for years. In our institute, however, all patients undergoing colorectal surgery are operated upon without these measures. The present study was undertaken to investigate the results of this strategy in terms of the occurrence of postoperative anastomotic leakage. METHODS: All patients who underwent an elective (low) anterior resection between January 1996 and December 2001 (n = 144) entered the study. The clinical and pathological records of these patients were reviewed retrospectively. The exclusion criteria were patients with fixed rectal carcinoma who received preoperative radiotherapy and/or a stoma only at operation, emergency operations, abdominoperoneal resections, and Hartmann's procedures. RESULTS: Anastomotic leakage occurred in 7 out of 144 patients (4.9%). There was a trend toward a higher leakage frequency in men, in patients with a distal anastomosis, in patients with a stapled anastomosis, and in patients with a T3-T4 tumor or with positive lymph nodes. None of these factors, however, had a significant prognostic value based on a univariate or multivariate analysis. Those who died after leakage tended to be older than those who did not (P < 0.05). CONCLUSION: A (low) anterior resection can be performed safely without mechanical bowel preparation or a diverting stoma, and results in an anastomotic leakage percentage of less than 5%. Appropriate selection of patients may be important, but none of the investigated patient- or tumor-related factors could be identified as decisive.

Adult↗

Endovascular treatment of popliteal artery aneurysms: results of a prospective cohort study.

OBJECTIVE: Popliteal artery aneurysms can be treated endovascularly with less perioperative morbidity compared with open repair. To evaluate suitability of the endovascular technique and the clinical results of this treatment, we analyzed a prospective cohort of consecutive popliteal aneurysms referred to a tertiary university vascular center. METHODS: All popliteal artery aneurysms between June 1998 and June 2004 that measured >20 mm in diameter were analyzed for endovascular repair. Anatomic suitability was based largely on quality of the proximal and distal landing zone as determined by angiography. Endovascular treatment was performed by using a nitinol-supported expanded polytetrafluoroethylene lined stent graft introduced through the common femoral artery. RESULTS: We analyzed 67 aneurysms in 57 patients. Ten aneurysms (15%) were excluded from endovascular repair, or from any repair at all, for various reasons. The remaining 57 (85%) were treated endovascularly, of which 5 were treated emergently for acute ischemia. During a mean 24-month follow-up, 12 stent grafts (21%) occluded. Primary and secondary patency rates were 80% and 90% at 1 year, and 77% and 87% at 2 years of follow-up. Postoperative treatment with clopidogrel proved to be the only significant predictor for success. CONCLUSIONS: Endovascular repair of a popliteal artery aneurysm is feasible. Changes in the material used and the addition of clopidogrel may improve patency rates.

Aged↗

Future of operating rooms.

Operating-room design has not changed significantly since the modern era of surgery began. Minimal invasive, endoscopic, procedures, and evolution of technology will affect operating-room design in the near future. Poor ergonomics has always been one of the major drawbacks of endoscopic surgery. Use of retractable arms and monitors will improve ergonomics of the operating team. Developments in telecommunication will allow surgeons to communicate with colleagues and experts during the procedure in virtually any location around the world, which increases teaching possibilities and procedural safety. Introduction and further development of intraoperative imaging, including real-time, three-dimensional (3-D) reconstructions of patient, and computer-aided surgery offer surgeons the opportunity to train the planned surgical procedure. Moreover, they will improve control and supervision of the procedure in learning situations. The last decade's robotics have made their introduction into the operating rooms. They improve control over the operating-room environment and will facilitate the performance of more complex procedures. However, high costs and lack of force feedback remain its major drawbacks. Improvements of robotic techniques and its implementation into the operating rooms will further guide their design into highly specialized operating units.

Ergonomics↗

Expanding use of nonpenetrating clips in various surgical specialities.

The Anastoclip Vessel Closure System (VCS) (LeMaitre Vascular, Burlington, MA, USA), introduced primarily to facilitate microvascular anastomoses performed during neurosurgical extra-intracranial bypasses, has been used for several other applications as well. The relatively new anastomotic technique includes a clip applier, clip remover, and everting forceps. With the applier, tiny nonpenetrating titanium clips were installed on everted walls of tubular structures. The technical ease of application, reduced anastomotic time, superior hemodynamics, and an improved healing pattern at the anastomosis have been recognized as major advantages compared to conventional suturing. This chapter describes the various indications for use of the system and categorizes them by specific surgical specialties, which include neurosurgery, urology, and gynecology, as well as plastic and reconstructive, vascular, thoracic, transplantation, hepatopancreaticobiliary, and orthopedic and trauma surgery. The largest clinical experience with clips is in vascular access surgery for hemodialysis purposes, both in autologous constructs and with prosthetic grafts. Promising clinical results also have been achieved in neurosurgical cases (both for microvascular anastomoses and with closure of dura mater), microvascular free-tissue transfer, and renal and liver transplantations. Future clinical applications include the use of clips for nerve repair and closure of various types of tubular structures using a laparoscopic approach.

Anastomosis, Surgical↗

Five years' world experience with nonpenetrating clips for vascular anastomoses.

BACKGROUND: A new sutureless technique has been introduced clinically to facilitate the process of vascular reconstruction and improve patency. The Vessel Closure System (VCS) is nonpenetrating, creates an elastomeric everted anastomosis, and is easily and reproducibly applied. The objective of this report is to review the published world experience that has accrued regarding these clips with attention to the assets, liabilities, and pitfalls associated with the new technology. DATA SOURCES: Medline search and manual cross-referencing were performed, after which 61 original articles were identified on the use of VCS clips for vascular anastomoses. RESULTS: Advantages of the clips compared with sutures include the technical ease of application, the reduced anastomotic time, the superior hemodynamics, and the improved healing pattern of the anastomosis. Disadvantages include the potential problems in atherosclerotic vessels, lack of prospective randomized long-term follow-up, and initial costs. The best clinical results have been achieved in microvascular repair, as well as with vascular access and transplantation surgery. CONCLUSIONS: The VCS clip technology has become an accepted vascular anastomosing technique, which in future could lead to the use of clips as a standard approach and the use of sutures only in case of severe atherosclerosis and other circumstances in which vessel edges are difficult to evert.

Anastomosis, Surgical↗

Anterior mediastinal presentation of a giant angiomyolipoma.

Angiomyolipomas are benign, solitary, noninvasive lesions that most often arise in the kidney. Extrarenal manifestations of these tumors include the skin, oropharynx, the abdominal wall, retroperitoneum, gastrointestinal tract, heart, lung, liver, uterus, penis, and spinal cord. We report a patient with a giant angiomyolipoma located in the anterior mediastinum. We believe this is the seventh reported case of mediastinal angiomyolipoma and the largest reported by size. It is the second reported lesion to arise in the anterior mediastinum. Distinction from other pulmonary or thoracic masses relies on the appreciation of the unique and characteristic histologic features of these mediastinal angiomyolipomas. We conclude that, although rare, angiomyolipoma should be considered in the differential diagnosis of a mediastinal tumor.

Adult↗