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J R Edgerton

Publications and source records attributed to J R Edgerton.

6 recordsLinked to original sources
PubMed2000

A review of 1,582 consecutive Octopus off-pump coronary bypass patients.

BACKGROUND: Off-pump coronary bypass may provide a safer form of surgical revascularization by avoiding the unwanted complications of cardiopulmonary bypass, particularly in the increasingly complex patients being referred for operation. This study reviews the entire experience of the Medtronic Octopus System (Medtronic, Minneapolis, MN) for beating heart bypass from 7 surgeons. Demographics, operative procedures, early outcomes, and trends in usage were examined. METHODS: Patients were selected for off-pump procedures by the individual surgeons. Data were entered prospectively into locally maintained databases and then collected for collation and analysis. RESULTS: A total of 1,582 consecutive Octopus patients were entered, representing the entire Octopus experience of each surgeon. Proportions of off-pump procedures relative to standard bypass increased over time, as did the percentage of patients receiving three or more grafts, 24.6% in 1997 and 55.9% in 1999. A total of 3,653 anastomoses were performed, 1,905 to the left anterior descending system, 837 to the circumflex distribution, and 911 to the right coronary territory. Morbidity was low. Few patients required conversion to cardiopulmonary bypass (2.6%; 0.2% urgently). Permanent stroke occurred in 0.6% and myocardial infarction in 1.2%. Operative mortality was 1%. CONCLUSIONS: Octopus off-pump bypass was demonstrated to be a safe procedure with widening applicability. With experience surgeons tend to apply the system to increasing proportions of their patients and are able to revascularize all coronary territories.

Aged↗
PubMed1994

Endothelial cell seeding of latissimus dorsi muscle pouches.

The transformation of skeletal muscle tissue into a fatigue-resistant, autologous blood pump is being explored as an attempt to aid the failing heart. One of the options is to generate a pouch underneath the latissimus dorsi muscle, to connect an electrically conditioned muscle pouch to the circulation, and to use it as an autologous, contractile cardiac assist device. However, the potential of thrombus formation on the blood contacting surface, which is composed of fibrous material, might thwart the clinical usefulness of such skeletal muscle ventricles. We hypothesized that the thrombogenicity of these pouches could be reduced by lining their luminal surfaces with autologous endothelial cells. As a first step, we examined the feasibility of this approach under resting, nonbeating conditions. Using a multistage operative procedure, we isolated microvascular endothelial cells from canine adipose tissue and, after culturing these cells in the laboratory, seeded the autologous cells into preformed latissimus dorsi pouches in six mongrel dogs. Four to six weeks later the dogs were sacrificed and the ultrastructure of the pouches was examined by light and electron microscopy and by fluorescence techniques. The micrographs confirmed that the surfaces of seeded pouches, but not of the untreated controls, are lined with a continuous monolayer of functional endothelial cells, as assessed by the presence of several endothelial cell-specific markers. Current studies are under way to assess the thrombogenicity of these endothelialized skeletal muscle pouches.

Adipose Tissue↗
PubMed1985

Zollinger-Ellison syndrome associated with persistently normal fasting serum gastrin concentrations.

A 63-year-old man with a 2-year history of upper gastrointestinal ulcers was found to have the Zollinger-Ellison syndrome. Despite histologic verification of gastrinoma, several fasting serum gastrin concentrations were normal. However, in response to intravenous secretin infusion, a paradoxical increase in serum gastrin levels indicative of gastrinoma was seen. Although serum gastrin concentrations in patients with suspected gastrinoma may be persistently normal, provocative testing may be necessary to establish the diagnosis of the Zollinger-Ellison syndrome.

Fasting↗
PubMed1983

Influence of aortic stenosis on the hemodynamic importance of coronary artery narrowing in dogs without left ventricular hypertrophy.

Coronary hemodynamic effects of controlled left ventricular outflow obstruction stimulating aortic valve stenosis were studied in 20 open-chest dogs, with and without graded coronary artery diameter narrowing. Aortic stenosis was regulated so that a mean left ventricular-aortic pressure gradient of 46 +/- 20 mm Hg (mean +/- standard deviation) was created as both heart rate and stroke volume were unchanged. In addition, during aortic stenosis, mean aortic pressure (105 +/- 17 to 84 +/- 15 mm Hg, p less than 0.05) and diastolic pressure time index/systolic pressure time index ratio (1.2 +/- 0.3 to 0.6 +/- 0.2, p less than 0.05) decreased and end-diastolic left ventricular pressure (7 +/- 4 to 14 +/- 6 mm Hg, p less than 0.05) increased. With no coronary narrowing, mean coronary flow increased during aortic stenosis (53 +/- 23 to 62 +/- 23 ml/min) as the percentage of diastolic flow increased (83 +/- 6 to 89 +/- 4) and endocardial/epicardial ratio decreased (1.14 +/- 0.16 to 0.95 +/- 0.24) (all p less than 0.05). Peak reactive hyperemic flow also decreased (168 +/- 85 to 125 +/- 73 ml/min, p less than 0.05). This value with no coronary narrowing was similar to peak hyperemic flow with 60% narrowing without aortic stenosis. With 90% coronary narrowing, mean coronary flow decreased with or without aortic stenosis. Transmural flow distribution also decreased but was lower during aortic stenosis (0.86 +/- 0.19 to 0.61 +/- 0.25, respectively; p less than 0.05). These data suggest that although mean coronary flow is increased during aortic stenosis, endocardial flow may be limited, and coronary reserve exposed during reactive hyperemia appears decreased. When a coronary artery is narrowed, aortic stenosis has an even more important hemodynamic influence on the coronary circulation.

Acute Disease↗