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E B Diethrich

Publications and source records attributed to E B Diethrich.

At least 19 recordsLinked to original sources
PubMed1992

Preliminary results of intraoperative excimer laser angioplasty: phase 1: an adjunct to coronary artery bypass surgery.

The excimer laser underwent phase I clinical trials at three centers to determine its safety for intraoperative coronary laser angioplasty as an adjunct to coronary artery bypass grafting. A 308-nm Xenon-Chloride, pulsed-wave excimer laser was used to perform angioplasty in 30 patients undergoing coronary artery bypass surgery. Forty vessels (30 patients) were treated, in which the extent of occlusion ranged from 30% to 100%, with complete occlusion in 40% of all vessels. Improvement in vessel luminal caliber was achieved in 33 (79%) vessels, with perforations occurring in 4 (12%) vessels, 2 of which required surgical repair. The lumens of the remaining 8 (19%) vessels were not enlarged, and 2 (5%) of these vessels were perforated. Luminal enlargement was most often achieved in totalled occluded vessels in which 16/17 (94%) were recanalized. No patients died within 30 days postoperatively. Five patients demonstrated biochemical and electrocardiographic evidence of myocardial injury 48 hr postoperatively, and one patient died of cardiac arrest 139 days postoperatively. On the basis of these results, we believe that excimer laser angioplasty can be performed safely to improve coronary luminal patency, even in totally occluded vessels, in an operative setting. The long-term value of this procedure remains to be elucidated.

Aged↗
PubMed1992

Angioscopy in endovascular surgery: recent technical advances to enhance intervention selection and failure analysis.

Recent technical and procedural modifications have greatly enhanced the usefulness of angioscopy during angioplasty. A pulsed irrigation system, proximal and distal blood flow control by pressure, and attention to sheath/vessel diameter ratio were incorporated into a study in which angioscopy was used for pretreatment assessment in 23 patients with symptomatic peripheral vascular disease presenting for initial (8 patients) evaluation or repeat treatment (15 patients) following a previous vascular procedure. Twenty-five lesions were examined with a 2.3 mm flexible angioscope equipped with an irrigating lumen; there were no complications attributable to angioscopy. The angioscope was useful in the characterization of lesions for selection of the recanalization technique. Lesions more amenable to initial atherectomy were visualized in 12 patients; 7 occlusions were successfully treated with laser/balloon angioplasty, with angioscopy assisting in probe and/or wire passage in 4 cases. Three late reocclusions were identified angioscopically as due solely to thrombosis, indicating the need for thrombolytic therapy. Angioscopy also identified 4 cases of incomplete recanalization despite a satisfactory arteriographic image. Angioscopy was also used to evaluate stenotic lesions unaccompanied by thrombus formation in patients previously treated with laser-assisted angioplasty. Histologic evaluation of the biopsied plaques identified intimal hyperplasia as the etiology, matching identically similar specimens harvested from a lesion treated with balloon dilation only.

Aged↗
PubMed1991

Relationship between foot transcutaneous oxygen tension and ankle systolic blood pressure at rest and following exercise.

To determine whether foot transcutaneous oxygen tension (TcPO2) and ankle systolic blood pressure (SBP) measure similar aspects of peripheral vascular occlusive disease (PVOD), the authors examined their relationship at rest and following treadmill exercise. Thirty-seven PVOD patients (mean age 69.2 +/- 0.8 years) rested supine for twenty minutes, followed by a progressive treadmill walking test at a constant speed of 2 mph. The initial grade was 0%; this increased 2% every two minutes until maximal claudication pain (n = 19) or until the occurrence of such limiting symptoms as volitional fatigue (n = 6), ST segment depression (n = 4), dyspnea (n = 3), multiple premature ventricular contractions (n = 2), and angina (n = 2). Patients then rested supine for fifteen minutes. Foot TcPO2 was recorded before, during, and after exercise, whereas ankle SBP was measured before and after exercise. At rest, a curvilinear relationship was found between foot TcPO2 and ankle SBP (foot TcPO2 = 41.89 + 0.22(ankle SBP) + 0.0005 (ankle SBP2); SEE = 9.2, R = 0.64, R2 = 0.41, p less than 0.001). In contrast, the relationship was stronger and more linear during recovery, particularly at the sixth minute (foot TcPO2) = 8.33 + 0.35 (ankle SBP); SEE = 13.6, R = 0.86, R2 = 0.73, p less than 0.001). At rest, foot TcPO2 and ankle SBP characterized different aspects of PVOD because they shared only 41% common variance. During recovery, they provided similar information because up to 73% of the variance was shared. It is concluded that foot TcPO2 should also be used to assess PVOD patients because unique information is obtained at rest and values can be recorded during exercise.

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PubMed1991

Laser-assisted angioplasty in the treatment of prosthetic graft stenosis.

Late failure of peripheral bypass grafts has been treated primarily by secondary reconstruction. Laser-assisted angioplasty is an optional therapy that the authors investigated in 28 prosthetic grafts over a two-year period. Twenty-five symptomatic patients with 28 peripheral prosthetic arterial bypass grafts (25 polytetrafluoroethylene [PTFE] grafts and 1 each of knitted Dacron, Teflon, and umbilical vein) demonstrated graft occlusion (25) or high-grade stenoses (3). All patients underwent standard laser-assisted angioplasty using a continuous wave Nd:YAG laser source and hybrid probe. Twenty-one grafts (75%) were successfully recanalized with adequate restoration of flow through the conduit. All 7 failures were in occluded PTFE grafts that presented with either recalcitrant lesions (5) or perforations (2) at the distal anastomoses. There have been 3 long-term failures (14%) to date in the successfully treated group, all in PTFE grafts. Two patients suffered recurrent thrombosis and 1 developed an inexplicable graft infection five months after laser treatment. Laser-assisted angioplasty appears to be a clinically viable alternative treatment for prosthetic graft stenosis and recanalization of grafts occluded at their distal anastomosis.

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PubMed1990

Intraoperative coronary excimer laser angioplasty: preliminary clinical experience.

Diffuse coronary artery atherosclerosis is generally recognized as a deterrent to successful revascularization if it cannot be adequately treated. Mechanical endarterectomy can be useful, but it is not the optimal solution owing to the associated higher incidences of perioperative infarction and mortality. The use of laser energy as an endarterectomy tool appears promising. To investigate the application of excimer laser radiation to intraoperative coronary artery endarterectomy, 15 stenotic lesions in 13 patients were treated with excimer irradiation during coronary artery bypass grafting. Eleven (73%) of the lesions were enlarged by the excimer probe (6 of the successes were in calcified lesions). The 4 arteries not enlarged by the excimer laser all demonstrated calcified lesions. There were 3 perforations and 2 dissections, all but 1 in heavily calcified arteries. The results of this phase 1 safety and efficacy study indicate that excimer irradiation can recanalize most arteries, including total and subtotal occlusions and some calcified lesions. Further evaluation with better delivery systems is needed to determine whether the perforation rate can be reduced.

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PubMed1989

The spoof factor.

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Angioplasty, Balloon↗
PubMed1989

Acute.

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Education, Medical, Continuing↗
PubMed1989

Applications and limitations of laser-assisted angioplasty.

Laser-assisted angioplasty is rapidly evolving into a promising adjunct to or replacement for standard vascular procedures. A protocol was devised to evaluate the technique in a non-selected, consecutive patient population to define the applications and limitations of the technique. In a 12-month period, 358 lower-limb atherosclerotic lesions were treated with laser/balloon angioplasty [percutaneously (52%) or open (48%)] in 206 consecutive patients. Overall, the laser/balloon technique recanalised 234 lesions (65% laser success), judged clinically effective by a greater than 0.15 improvement in the ankle/brachial index and elimination of symptoms. Operative complications included: perforation (15, 4.2%); thrombosis (16, 4.5%); spasm (5, 1.4%); and false aneurysm at the puncture site (7, 2.0%). Of the 124 failures (35%) categorised for analysis, the most common cause was inability to cross the lesion in 20 cases. This experience has identified three significant clinical limitations to successful laser recanalisation: calcification, inadequate distal circulation, and inability to control restenosis/reocclusion (collapsible lesions and accelerated plaque deposition). Further research is needed to determine if thermal injury seriously compromises the safety and long-term outcome of laser-assisted angioplasty.

Adult↗