Management of coexistent carotid and coronary artery disease.

Simultaneous coronary artery bypass grafting (CABG) and carotid endarterectomy (CE) were done on 133 patients over an 8-year period. Twenty-seven patients (20%) had previous transient ischemic attacks (TIAs), 12 (9%) had previous strokes, and the remainder (71%) were asymptomatic. All asymptomatic patients had greater than 85% stenosis of the internal carotid artery demonstrated by noninvasive ultrasonography and four-vessel angiography. CE was performed prior to the sternotomy for coronary artery bypass, under the same anesthesia. Nineteen patients had bilateral carotid artery disease. Postoperatively, three patients (2.3%) suffered strokes, an additional three patients (2.3%) suffered transient upper extremity weakness, and one patient from each of these groups died. There were no postoperative strokes or TIAs in patients with bilateral carotid artery disease. Average length of hospital stay was 10 days. Our experience leads us to conclude that the morbidity and mortality of the simultaneous procedure are not affected by bilateral carotid artery disease. In patients with symptomatic coronary artery disease and symptomatic carotid artery disease or asymptomatic carotid artery disease with a high-grade stenosis, we think that simultaneous repair of both lesions should be done.

Laparoscopy and the general surgeon.

Laparoscopic cholecystectomy has belatedly awakened the general surgical community to the concept of closed abdominal surgery. Current techniques have largely been developed by our colleagues in gynecology. The unanticipated demand by the public has placed unprecedented pressure on our systems for training, credentialing, developing, supplying, and evaluating changes in surgical technique. The diagnostic value of laparoscopy has been documented by a handful of general surgeons over the past several decades and is likely to become a more widely accepted technique. The potential of future developments in video-controlled operations is immense.

Occluded peripheral arteries: clinical utility of argon laser recanalization.

Optically diverged direct argon laser light energy was used prior to conventional balloon angioplasty to recanalize 30 occluded peripheral arteries in 26 patients. Three of five (60%) iliac and 22 of 25 (88%) femoropopliteal lesions ranging in length from 1 to 47 cm (mean, 17.3 cm) were successfully treated, for an overall technical success rate of 83%. In the femoropopliteal system, 13 of 14 (93%) procedures in lesions less than 20 cm and nine of 11 (82%) procedures in lesions greater than 20 cm were treated successfully. No statistically significant differences in success rate based on lesion site, lesion length, degree of lesion calcification, or severity of peripheral vascular disease were found. Major complications were a laser perforation resulting in treatment failure in one case (3%) and a successfully treated distal embolus in another (3%). No reocclusions occurred in the immediate postoperative period. While long-term follow-up will be required to assess continued patency, this system can potentially increase the number of patients amenable to conventional balloon angioplasty and is currently advocated as an alternative to amputation in patients in whom surgical bypass grafting is contraindicated or unfeasible.

Pseudo-occlusion of the internal carotid artery: how not to miss it.

Although pseudo-occlusion of the internal carotid artery has been previously reported, it is not widely appreciated. The purpose of this report is to demonstrate methods of making the diagnosis. We present two cases illustrating the angiographic findings in pseudo-occlusion of the internal carotid artery. Its recognition is important to the vascular surgeon in making recommendations for surgery.

Paradoxical embolization with Ebstein's anomaly.

A 48-year-old woman with known Ebstein's anomaly had bilateral, lower-extremity arterial emboli after a total abdominal hysterectomy. She underwent embolectomy, placement of a Greenfield caval filter, subsequent tricuspid valve replacement, and closure of an atrial septal defect. Antemortem diagnosis of a paradoxical embolus is rare. To our knowledge, this is the first case associated with this congenital cardiac anomaly in a survivor.

Transluminal angioplasty in a community hospital: a surgeon's viewpoint.

We have found transluminal angioplasty to be a safe and effective procedure for the relief of arterial obstruction. In a community hospital over a 20-month period, we did 100 consecutive dilatation procedures, many involving multiple dilatations, with no morbidity or mortality. Iliac lesions were dilated successfully (74/80) more often than femoral lesions (15/20). Several patients had relief of impotence. Transluminal angioplasty was used successfully as an adjunct to operation both as staged and combined procedures to dilate the donor artery for a femoral-femoral bypass graft or femoral-popliteal graft, or to dilate the outflow of a new or existing graft.

Correlative electrophysiological and anatomical studies concerning the site of origin of escape rhythm during complete atrioventricular block in the dog.

Complete heart block was produced in eight dogs by the selective perfusion of physostigmine or neostigm into the atrioventricular (AV) node artery. A characteristic escape AV junctional rhythm emerged in each dog. After reversal of the cholinesterase paralysis with atropine, in each dog partial heart block was produced by an incision into the AV nodal region. In three of these eight dogs, a second incision placed slightly more anteriorly produced complete AV block which was followed by the emergence of an escape AV junctional rhythm similar to the one produced pharmacologically. Hearts of these three dogs were examined histologically with serial sections to determine the exact location of the incisions and their relationship to the AV node and His bundle. In each dog the incision that produced complete heart block passed directly through the junction of AV node with His bundle. In this region previous studies had demonstrated numerous P cells, which are thought to be the site of origin of normal cardiac automaticity. In each of the three hearts there were abundant P cells in continuity with the His bundle distal to the cut producing heart block. Significance of these findings is discussed relative to the locus of action of acetylcholine within the AV junction, the site of origin of AV junctional rhythm, and sme aspects of the experimental and therapeutic production of heart block.

Chronotropic and dromotropic effects of histamine on the canine heart.

The actions of 2-methylhistamine (H1 agonists), 4-methylhistamine (H2 agonist), and histamine were studied by selective perfusion of the sinus node artery and atrioventricular node artery in 75 dogs anesthetized with pentobarbital sodium. 2-Methylhistamine and histamine had variable and inconsistent effects on the sinus rate. 4-Methylhistamine (100 microgram/ml) produced acceleration of the sinus rate from 158 +/- 4 to 173 +/- 5 beats per minute (P less than 0.05) when perfused via the sinus node artery. The effects of the histamine agonists on atrioventricular junctional rhythms were similar to the effects on sinus rhythm. The response of the sinus node to vagal stimulation was attenuated by selective perfusion with histamine; however, the direct negatively chronotropic action of acetylcholine was not affected by histamine. Neither 2-methylhistamine nor 4-methylhistamine affected the response of the sinus node to vagal stimulations. Both 4-methylhistamine and histamine (but not 2-methylhistamine) attenuated (P less than 0.05) the response of the sinus node to stimulation of the right stellate ganglion. The positively chronotropic effects of directly perfused norepinephrine were unaffected by histamine or 4-methylhistamine. These results suggest a neural depressing action of histamine on autonomic efferent fibers. In the atrioventricular junction, both histamine and 2-methylhistamine (but not 4-methylhistamine) had negatively dromotropic effects. Cimetidine (an H2 antagonist) had no significant direct effects on the sinus rate or atrioventricular conduction and failed to prevent the acceleration of the sinus rate produced by local perfusion with 4-methylhistamine.

Analysis of components in a cardiogenic hypertensive chemoreflex.

A cardiogenic hypertensive chemoreflex was studied in 38 anesthetized and three unanesthetized dogs. Serotonin (100 mug/ml) injected into either the left atrium or small brancehes of the proximal left coronary artery produced a maximal response, with 96 +/- 18 mm Hg increment in mean aortic pressure within 6 +/- 2 seconds, lasting about 1 min; a later phase of the same hypertension lasted 9 +/- 5 minutes more and could partially be produced with serotonin injected into the thoracic aorta. Injections into the distal left coronary artery produced only the Bezold-Jarisch reflex. Concomitant with the immediate hypertension there were vagal and sympathetic efferent effects in both the sinus node and the atrioventricular (A-V) junction. Either of these effects could be selectively eliminated and the other augmented by direct local perfusion with an appropriate cholinergic (atropine 10 mug/ml) or adrenergic beta-receptor (propranolol 10 mug/ml) blocking agent. Bilateral vagotomy markedly attenuated but did not eliminate the acute hypertension, but it abolished both chronotropic and dromotropic effects. Phentolamine (2 mg/min i.v.) markedly diminished the hypertensive response. Guanethidine or reserpine pretreatment markedly diminished the hypertensive response; reserpine eliminated the electrophsiologic effects but guanethidine did not. Infiltration of serotonin around the main left coronary partially reproduced the reflex, but similar infiltration of xylocaine hydrochloride blocked the reflex. Serial section histologic studies of the region around the main left coronary atery in seven dog hearts and nine human hearts demonstrated the presence of a small structure resembling a chemoreceptor; its blood supply originated from the left coronary artery. Some possible clinical implications are discussed.

Direct and vagally mediated chronotropic effects of morphine studied by selective perfusion of the sinus node of awake dogs.

Two milliliters of a morphine sulfate solution (1 mg/ml) perfused selectively into the sinus node artery of five trained unanesthetized dogs caused an immediate brief sinus tachycardia followed by a delayed but prolonged sinus bradycardia. Beta-receptor blockade was achieved by selective perfusion of propranolol hydrochloride solution (10 mug/ml) into the sinus node artery and did not prevent the initial sinus tachycardia. Selective perfusion of the sinus node with atropine sulfate solution (1 mug/ml), however, did prevent morphine from causing further sinus rate increase. The immediate positive chronotropic action of morphine was thus attributable to a peripherally located vagolytic action. The exact opposite was true with regard to the delayed bradycardia; it was due to a centrally mediated generalized increase in vagal tone regularly elicited by morphine.