Transluminal atherectomy for occlusive peripheral vascular disease.

Sixty-one patients with occlusive peripheral vascular disease were treated with transluminal atherectomy, a catheter-mediated technique for removal of atheroma. The technique was performed using 7Fr, 9Fr or 11Fr atherectomy catheters. Mean percent diameter stenosis was reduced from 71 to 23%, by removal of 831 atheromatous specimens in 949 passes of the cutting element through 136 stenoses in 61 patients. All specimens removed were sent for histopathologic examination to determine the components of the atheroma removed, which differed for specimens removed from original vs restenotic lesions. Percent stenosis was reduced to less than 45% in 118 of 136 stenoses (87%). Complications included 1 thrombus, which resolved after intraarterial infusion of streptokinase and 1 probable distal embolization without sequelae. Three angiographic dissections occurred without impairment of blood flow. There were no instances of acute occlusion, vascular spasm or vessel perforation. Six-month follow-up angiography was performed showing that patients who had a residual stenosis less than 30% after initial atherectomy had a lower restenosis rate (18%) than patients with initial residual stenoses greater than 30% (52%); this result demonstrated the importance of performing more complete atherectomy. Transluminal atherectomy appears to be an effective, predictable and safe method for removing occlusive atheromatous deposits from peripheral arteries.

Provocation of coronary spasm with ergonovine maleate. New test with results in 57 patients undergoing coronary arteriography.

Ergonovine maleate (Ergotrate) was given to 57 patients undergoing coronary arteriography for investigation of angina occurring at rest or without provocation when routine study showed normal arteries or insufficient occlusive disease to explain their symptoms. This provocative test induced coronary arterial spasm in 13 patients, 10 of whom had definite Prinzmetal's angina. The spasm was easily reversed with sublingually administered nitroglycerin. The spasm was occlusive or nearly occlusive in nine patients, and there was associated reproduction of the chest pain and S-T elevation similar to the spontaneous episodes. One patient with Prinzmetal's angina had S-T depression rather than elevation in association with the chest pain. The other three patients without Prinzmetal's angina had focal narrowing without coronary occlusion, reproduction of the chest pain or electrocardiographic changes. Of the 44 patients who did not demonstrate coronary spasm in response to ergonovine, 29 had normal coronary arteries and 15 had various degrees of atherosclerotic occlusive disease. We conclude that cautious administration of ergonovine maleate during coronary arteriography can be safely used to elicit coronary spasm in some patients who have insufficient fixed occlusive disease to explain their symptoms.

Palmar arteriography in acronecrosis.

Palmar arteriography in patients with acronecrosis complicating collagen vascular disease demonstrated multiple occlusions and stenoses which were most severe in the proper digital arteries. Involvement was prevalent at points of manual stress, i.e., adjacent to metacarpal-phalangeal and interphalangeal joints. An additional observation was the presence of incomplete superficial and deep palmar arches in all instances, a finding which diametrically contrasts with anatomical studies purporting to demonstrate complete palmar arches in 80% of the normal population.

Balloon embolectomy catheter used percutaneously.

Percutaneous arterial embolectomy was performed following percutaneous transluminal angioplasty in three patients using Fogarty balloon embolectomy catheters. This technique is effective for the treatment of arterial embolism resulting from angioplasty in selected situations.

Intraarterial analgesia in peripheral arteriography.

A pilot study involving 36 patients was undertaken to test the efficacy of combining 1% lidocaine with 60% methylglucamine iothalamate for relief of the severe burning pain often experienced during peripheral arteriography. Of 24 patients premedicated with meperidine hydrochloride and promethazine hydrochloride, 12 received lidocaine with the contrast medium and 12 did not. The remaining 12 patients were premedicated with diazepam and received lidocaine with the contrast material. By both subjective and objective criteria, those patients receiving lidocaine in the intraarterial injection of contrast medium suffered less pain. Optimum results were achieved for the lidocaine group receiving analgesic premedication. No adverse reactions attributable to the lidocaine were encountered. Subsequent to completion of the pilot study, more than 300 patients have been studied with similar impressive results of pain relief and safety.

An unusual form of the transposition complex. Uncorrected levo-transposition with horizontal ventricular septum: Report of two cases.

A distinctive angiographic appearance is described in two patients who had uncorrected levo-transposition of the great vessels. Although levo-transposition with inversion of the ventricles usually results in physiologically corrected transposition, in these patients the anatomy was arranged in such a way as to result in an uncorrected transposition. The following elements were responsible for this physiological condition: normal atrial situs, inverted ventricles with "criss-cross" atrioventricular flow, levo-transposed great arteries. In addition, the morphological right ventricle was hypoplastic, left sided and superior to the left ventricle and the ventricular septum was horizontal in position. The two ventricles were connected via a large ventricular septal defect. The importance of accurate, detailed, preoperative angiographic demonstration of the anatomic situation is stressed.

Spontaneously and pharmacologically provoked coronary arterial spasm in Prinzmetal variant angina.

Eleven of 21 consecutive patients with Prinzmetal angina (PMA) exhibited no significant fixed stenoses of the coronary arteries. Spontaneous coronary arterial spasm was demonstrated in 3 patients. Ergonovine maleate produced near-total occlusion of a major vessel in 3 of 4 other patients with PMA, but did not provoke spasm in 10 without PMA. The current study documents spasm as the mechanism of myocardial ischemia in some patients with normal coronary arteries and provides initial and favorable diagnostic results with provocative pharmacoangiography in this entity.

Shear force in angioplasty: its relation to catheter design and function.

The inability to successfully position angioplasty catheters and the occurrence of complications during angioplasty procedures can, in part, be related to the shear forces generated during catheter introduction. Shear forces are the axial contact forces that the catheter system exerts on the inner arterial surfaces during advancement. The shear forces exerted by three different catheter designs (coaxial dilator, coaxial balloon, and linear extrusion) were measured in normal and atherosclerotic arteries; in modeled stenoses of variable severity, length, and compliance; and in modeled vessel angulations. The results with modeled vessels show that the linear extrusion catheter reduces the level of shear forces, particularly in narrow, long, noncompliant stenoses and in tortuous vessels. The stenotic artery results also show that the linear extrusion catheter minimizes these forces in tight lesions. The relative differences in forces are explained by the mechanism of action for each catheter. The reported occurrences of technical difficulties, complications, and long-term patency rates are then interpreted on the basis of the relative differences in measured shear forces. The results of this study combined with preliminary clinical data indicate that linear extrusion should facilitate placement and reduce associated complications.

Transluminal angioplasty: a mechanical-pathophysiological correlation of its physical mechanisms.

We quantitatively determined the relative contribution of various factors leading to arterial lumen enlargement during transluminal angioplasty. Mechanical tests were conducted on both normal and atherosclerotic artery necropsy specimens. In our range of dilating pressures (0-3.4 atm or 0-50 lb/in2), content extrusion of fluid from the plaque accounted for 6-12% of the overall lumen area increase, while compaction of the plaque accounted for only 1-1.5%. The majority of the increase, 86.8-93%, was due to plaque and arterial wall disruption. The mechanism of disruption began with shearing of the plaque from the underlying artery at relatively low dilating pressures and continued with longitudinal tearing and stretching of the arterial wall at higher pressures. Diseased arteries dilated significantly more than nondiseased arteries at dilating pressures greater than or equal to 1.36 atm or 20 lb/in2 (P less than .05). In the range of stenoses that were tested (10-50%), the mean dilating pressure required to increase the lumen cross-sectional area by 50% was approximately 1.5 atm or 22 lb/in2.

Real-time B-mode carotid imaging. A three-year multicenter experience.

This report attempts to establish the place of real-time B-mode carotid imaging in the diagnosis of carotid artery disease through an analysis of the results of 3 years of experience in three major noninvasive vascular laboratories. Over 7000 patients were studied noninvasively with real-time B-mode carotid imaging and oculoplethysmography (OPG). Angiographic comparisons of 1723 vessels form the basis of this study. All tests were interpreted by physicians who had no knowledge of the angiograms. Images and x-ray films were classified by diameter of stenosis: grade I (0% to 39%), grade II (40% to 69%), grade III (70% to 99%), and grade IV (total occlusion). The effect of the imaging experience was determined by dividing the study into two periods. The results of image quality vs. accuracy and of combining the anatomic study (scan) and physiologic study (OPG) were also evaluated. The overall data show a specificity of 87% (985 of 1139), a sensitivity for grade II disease of 72% (193 of 267), a sensitivity for grade III of 66% (133 of 201), and a sensitivity for grade IV of 64% (74 of 116). With experience each center showed improvement of the imaging technique in diagnosing grade III (p greater than 0.1: not significant) and grade IV disease (p less than 0.0002: highly significant), although there was no improvement in the specificity and sensitivity of grade II disease. All scan errors were analyzed. Most errors were interpretation errors (27%: 90 of 338), scan/arteriogram mismatches (23%: 79 of 338), or poor-quality scans secondary to existing disease (22%: 75 of 338). There was a direct correlation of scan quality and accuracy, with a 97% specificity for grade I scans of good to excellent quality. When the scan and OPG agreed, there were uniform predictive values for all grades (88% to 93%). Sixteen of 79 scan/arteriogram mismatch vessels were operated on, and the scan proved more reliable in 86%. Real-time B-mode carotid imaging is a reliable technique for defining the normal carotid artery and is becoming increasingly sensitive in identifying existing disease. Despite its limitations, its strong points make it a valuable clinical tool.