PubMed Health⌕ Search

Biomedical subjects

J B Prewitt

Publications and source records attributed to J B Prewitt.

2 recordsLinked to original sources

Reduction in the rate of early restenosis after coronary angioplasty by a diet supplemented with n-3 fatty acids.

To determine the safety and benefit of n-3 fatty acid therapy in the prevention of early restenosis after coronary angioplasty, we conducted a randomized, unblinded study comparing a conventional antiplatelet regimen (325 mg of aspirin and 225 mg of dipyridamole per day; control group) with a similar regimen supplemented with 3.2 g of eicosapentaenoic acid per day (treatment group). Treatment began seven days before angioplasty and continued for six months afterward. All angiographic analyses were blinded and performed by a method that was validated by comparison with quantitative coronary angiography. In 82 male patients, 103 coronary lesions were dilated. Both groups had similar base-line clinical and angiographic characteristics. The incidence of early vessel restenosis, as determined on a second angiogram three to four months after angioplasty, was 36 percent in the control group and 16 percent in the treatment group (P = 0.026). The incidence of restenosis per patient was also significantly lower in the treatment group (46 vs. 19 percent). Both multiple logistic regression and Mantel-Haenszel statistical analyses demonstrated a significant independent benefit of treatment with n-3 fatty acids. No important bleeding complications developed in the treated patients. These results, in a male population at relatively high risk for restenosis, suggest that a dietary supplement of n-3 fatty acids, administered for one week before and for six months after coronary angioplasty, is safe and reduces the occurrence of early restenosis after that procedure. Whether this beneficial effect also applies to other populations is unknown.

Angioplasty, Balloon↗

Plasma serotonin concentrations: validation of a sampling technique using long catheters.

Serotonin is released by activated platelets and may promote platelet aggregation and epicardial coronary artery constriction in animal models. Serotonin may have similar effects in humans and, thus may be a mediator of certain ischemic syndromes. However, the role of serotonin in human ischemic heart disease has not been studied. Since evaluation of transcardiac serotonin metabolism requires that blood samples be obtained through long catheters, it is possible that artifactual changes in serotonin concentration could occur because of platelet activation in the catheters themselves. Accordingly, to determine if serotonin could be measured through long catheters without artifactual changes, the authors obtained paired blood samples by gentle aspiration through a large bore steel needle and a 100-cm polyurethane catheter placed in the femoral vein of 13 patients. All samples were processed to obtain platelet-poor plasma and then analyzed by a sensitive radioenzymatic assay. Blood sampling through long catheters did not cause a systematic alteration in plasma serotonin concentration. Mean serotonin concentration from the femoral vein through a needle was 22.3 +/- 26.55 ng/ml (mean +/- standard deviation), and that obtained through a long catheter was 20.0 +/- 26.29 ng/ml (p = 0.34). The authors conclude that carefully obtaining blood samples through long catheters does not significantly alter the plasma serotonin concentration and thus the accurate measurement of transcardiac serotonin concentrations is possible using these methods.

Blood Platelets↗