Acute and long-term outcome after Palmaz-Schatz stenting: analysis from the New Approaches to Coronary Intervention (NACI) registry.

The randomized Stent Restenosis Study (STRESS) and Belgium Netherlands Stent (Benestent) trials established that elective use of Palmaz-Schatz stents (PSSs) in native coronary arteries with de novo lesions is associated with increased procedural success and reduced restenosis. However there are other clinical indications for which stents are commonly used (unplanned use, vein grafts, restenosis lesions) that are not addressed in these studies. From 1990-1992, 688 lesions in 628 patients were treated with PSSs in the New Approaches to Coronary Intervention (NACI) registry. Angiographic core laboratory readings were available for 543 patients (595 lesions, of which 106 were stented for unplanned indications, 239 were in saphenous vein bypass grafts, and 296 were previously treated). The cohort of patients in whom stents were placed for unplanned indications had more women, current smokers, and had a higher incidence of recent myocardial infarction (MI). Patients who underwent stenting of saphenous vein grafts were older, had a higher incidence of diabetes mellitus, unstable angina, prior MI, and congestive heart failure. Lesion success was similar in all cohorts (98%), but procedural success was significantly higher for planned stenting (96% vs 87%; p < 0.01). Predictors of adverse events in-hospital were presence of a significant left main stenosis and stenting for unplanned indication. The incidence of target lesion revascularization by 30 days was significantly higher for patients undergoing unplanned stenting due to a higher risk for stent thrombosis. Recent MI, stenting in native lesion, and small postprocedural minimum lumen diameter independently predicted target lesion revascularization at 30 days. Independent predictors of death, Q-wave myocardial infarction, or target lesion revascularization at 1 year included severe concomitant disease, high risk for surgery, left main disease, stenting in the left main coronary artery, and low postprocedure minimum lumen diameter.

Immediate results and late outcomes after stent implantation in saphenous vein graft lesions: the multicenter U.S. Palmaz-Schatz stent experience. The Palmaz-Schatz Stent Study Group.

OBJECTIVES: This study reports the multicenter registry experience evaluating the safety and efficacy of the Palmaz-Schatz stent in the treatment of saphenous vein graft disease. BACKGROUND: Saphenous vein graft angioplasty is associated with frequent periprocedural complications and a high frequency of restenosis. Stent implantation has been shown to reduce restenosis, with improved long-term outcomes in the treatment of native coronary artery disease. Preliminary experience with stent placement in the treatment of saphenous vein graft lesions has been favorable. METHODS: Twenty U.S. investigator sites enrolled a total of 589 symptomatic patients (624 lesions) for treatment of focal vein graft stenoses between January 1990 and April 1992. Follow-up angiography was performed at 6 months, and the clinical course of all study patients was prospectively collected at regular intervals for up to 12 months. RESULTS: Stent delivery was successful in 98.8% of cases, and the procedural success rate was 97.1%. The lesion diameter stenosis decreased from 82 +/- 12% (mean +/- SD) before to 6.6 +/- 10.2% after treatment. Major in-hospital complications occurred in 17 patients (2.9%); stent thrombosis was found in 8 (1.4%); and major vascular or bleeding complications were noted in 83 (14.3%). Six-month angiographic follow-up revealed an overall restenosis rate (> or = 50% diameter stenosis) of 29.7%. Multivariate logistic regression analysis indicated that 1) restenotic lesions, 2) smaller reference vessel size, 3) history of diabetes mellitus, and 4) higher percent poststent diameter stenosis were independent predictors of restenosis. The 12-month actuarial event-free survival was 76.3%. CONCLUSIONS: Stent implantation in patients with focal saphenous vein graft lesions can be achieved with a high rate of procedural success, acceptable major complications, reduced angiographic restenosis and favorable late clinical outcome compared with historical balloon angioplasty control series. The rigorous anticoagulation regimen after stent placement results in more frequent vascular and other bleeding complications. Future randomized studies comparing standard balloon angioplasty with stent implantation are warranted to properly assess the full impact of stent placement in the treatment of saphenous vein graft lesions.

Long-term angiographic and clinical outcome after implantation of balloon-expandable stents in aortocoronary saphenous vein grafts.

Balloon angioplasty of aortocoronary saphenous vein graft lesions is associated with high restenosis and clinical event rates. The goal of this multicenter study was to assess long-term angiographic and clinical outcome of patients electively treated with single Palmaz-Schatz stents in aortocoronary saphenous vein grafts. In 198 patients (209 lesions), elective placement of single Palmaz-Schatz stents was attempted. Angiography was performed at baseline, immediately after stent placement, and at 6-month follow-up. Stent placement was successful in 98.5% of patients. One patient (0.5%) had stent thrombosis. Restenosis occurred in 34% (45 of 133) of the restudied lesions. Restenosis was lower in de novo lesions than in restenotic lesions (22% vs 51%, p < 0.001). Ostial lesions had a higher restenosis rate than nonostial lesions (61% vs 28%, p = 0.003). Freedom from death, myocardial infarction, coronary artery bypass surgery, and repeat angioplasty was present in 70% of patients. Eighty-two percent of patients with de novo lesions remained event-free at 1 year, whereas only 55% of patients with prior angioplasty were event-free at 1 year (p < 0.001). The use of the Palmaz-Schatz stent for the treatment of focal, de novo, aortocoronary saphenous vein graft lesions is associated with a high procedural success rate, a low angiographic restenosis rate, and low clinical event rates, including the need for repeat revascularization. The results of this study need validation by a prospective randomized trial comparing stent implantation with angioplasty.

Aortoesophageal fistula secondary to thoracic aortic aneurysm repair.

The development of a fistula between the aorta and the oesophagus after graft replacement of the thoracic aorta is extremely rare. We report a case which occurred 3 years and 7 months after repair of an aneurysm of the descending thoracic aorta and review the previous reports of this uniformly fatal condition.

Monocyte esterase deficiency in gastrointestinal cancer.

AIM: To substantiate the high incidence of monocyte esterase deficiency (MED) in gastrointestinal carcinoma already reported in a small group of patients; to compare the clinical findings in esterase deficient and esterase positive patients. METHODS: Peripheral blood smears (n = 22) or cytocentrifuge preparations (n = 52) of mononuclear cells from the peripheral blood of patients with gastrointestinal carcinoma were stained by the non-specific esterase stain (pH 5.8) using a batch technique. Samples containing > or = 85% esterase negative monocytes were identified at light microscopic examination. RESULTS: Seven of 74 patients were identified as having MED. This correlated exactly with the proportion (five of 46) found before, using an automated method, and was significantly higher than the 0.8% incidence in normal blood donors shown in that study. Comparison of the clinical details of the 12 MED patients with those of 105 esterase positive patients showed a significantly longer disease free survival in the MED cohort and increased occurrence of benign neoplasms--largely colorectal polyps--in this group also. Three patients had a borderline degree of deficiency and were excluded from comparisons, although they showed the same clinical tendencies as the MED group. CONCLUSIONS: There is a strong degree of association between monocyte esterase deficiency and gastrointestinal carcinoma. Further evidence must be sought to prove that the deficiency precedes the disease and therefore may predispose to it, or at least may identify subjects with such a predisposition. This could lead to early diagnosis and effective treatment of gastrointestinal carcinoma in a sizeable proportion of patients.

Does vasectomy cause testicular cancer?

Between 1975 and 1990, 330 men developed testicular tumours in Northern Ireland. Their names were cross matched with a sample of 2904 men who had undergone vasectomy between 1970 and 1985. The expected numbers of tumours in vasectomised patients was 2, while the actual number was 1. Our experience does not indicate that vasectomy causes testicular cancer.

PIP: The overall incidence of testicular cancer, like vasectomy, is increasing. A recent report from Scotland suggests a link between the two. This study was conducted to investigate any association between vasectomy and the subsequent development of testicular cancer. Over the period 1975-1990, 330 men developed testicular tumors in northern Ireland. Their names were cross-matched with a sample of 2904 men who had undergone vasectomy between 1970 and 1985. Researchers expected 2 tumors in vasectomized patients, but found only 1. The authors' experience does not suggest that vasectomy causes testicular cancer.

Day-case arteriography.

Outpatient femoral arteriography has been carried out in 100 consecutive patients presenting with evidence of peripheral vascular disease. Patients have been observed for seven hours in an observation ward bed. No bleeding or other complications have been encountered. The cost-saving to the hospital is approximately 60.00 pounds per case. More importantly, the service to patients has been improved, with less chance of last minute cancellation due to unavailability of a surgical bed.

Tartrate resistant acid phosphatase positive splenic lymphoma: a relatively benign condition occurring in a time-space cluster?

Conventional light and electron microscopic studies, together with cytochemical and immunocytochemical staining procedures, were carried out to ascertain whether the lymphomata of four elderly female patients living within 10 kilometers of each other, who presented within a short space of time with massive splenomegaly and varying cytopenia, belonged to any particular subgroup of lymphoma. In each case the lymphoma had a diffuse pattern and mature B cell phenotype. The malignant cells were of uniform cell type, slightly larger than admixed polymorphonuclear leucocytes, and showed minimal nuclear irregularity and positivity for tartrate resistant acid phosphatase (TRAP) staining. Their clinical and morphological features were compared with those of other lymphoproliferative disorders, but while sharing some features in common with each condition, this small group of patients seemed to have a unique combination of findings. The cytopenias of all four responded well after removal of the spleen and their disease has not been aggressive. It is concluded that these patients have a distinct subgroup of lymphoma, which it is important to recognise so that inappropriate use of aggressive cytotoxic drugs can be avoided.

Experience with the use of coronary autoperfusion catheter during complicated angioplasty.

Between February and July of 1989, 22 patients underwent the use of the Stack autoperfusion catheter following acute occlusion or obstructive dissection during coronary angioplasty; in 20 cases conventional balloon was used in an attempt to correct the angiographic appearance followed by the use of Stack catheter when results were sub-optimal. Only 1 patient (4.5%) required surgical revascularization. Although our study is not prospective or randomized, our observations suggest a significant impact in decreasing the need for emergency surgical revascularization after complicated coronary angioplasty with the use of this approach.

Evidence for autocrine growth stimulation of cultured colon tumor cells by a gastrin/cholecystokinin-like peptide.

The peptide gastrin has been shown to have growth stimulatory effects on normal as well as malignant gastrointestinal tissue. In this study, we have examined the possibility of autocrine growth-stimulation of cultured colon tumor cells by a gastrin-like peptide. The gastrin/CCK receptor antagonist dibutyryl cGMP inhibited the proliferation of two human colon carcinoma cell lines HCT 116 (EC50 = 1.3 mM) and CBS (EC50 = 2.5 mM) in a dose-dependent manner. Marked morphological changes were observed in HCT 116 cells after treatment with 1 mM dibutyryl cGMP. In receptor binding assays, dibutyryl cGMP competed with 125I-labeled gastrin for binding to HCT 116 cells (IC50 = 1.8 mM). Another derivative of cyclic GMP, 8-Bromo cGMP used as control due to its considerably weaker affinity for the gastrin/CCK receptor, did not compete with radiolabeled gastrin for binding to HCT 116 cells and had no effect on the morphology or proliferation in monolayer cultures of HCT 116 or CBS cells at concentrations up to 10 mM. Antigastrin/CCK antisera was also found to have dose-dependent cytostatic effects on HCT 116 and CBS cells adapted to growth in serum-free medium. The antiproliferative effect of the gastrin/CCK receptor antagonist and antigastrin/CCK antibodies suggested that a gastrin-like peptide secreted by these cells may promote growth. Radioimmunoassay of the conditioned medium of these two cell lines indicated the presence of a gastrin-like peptide (10-50 pg/10(6) cells/72 h). Northern analysis using an oligonucleotide DNA probe complementary to the nucleotide sequence coding the dodecapeptide carboxyl terminal of human gastrin showed three transcripts (0.7, 3.3, and 3.7 kb) that hybridized with the probe. These data provide, for the first time, evidence for an autocrine growth stimulatory role of a gastrin/CCK-like peptide in cultured colon tumor cells.

Antiproliferative effects of gastrin receptor antagonists and antibodies to gastrin on human colon carcinoma cell lines.

The gastrointestinal hormone gastrin has been shown to stimulate the growth of normal colonic mucosa. To examine for a possible role of gastrin in the proliferation of cultured colon tumor cells, we have studied the effects of two gastrin receptor antagonists, proglumide and benzotript, and of antibodies to gastrin. We find that proglumide (50% effective concentration, 2 to 5 mM) and benzotript (50% effective concentration, 0.4 to 0.8 mM) inhibit the monolayer growth of six human colon cancer cell lines. Addition of exogenous gastrin abrogated the growth-inhibitory effect of proglumide. The anchorage-independent growth of colon carcinoma cells was also inhibited by the two gastrin antagonists. Also, a dose-dependent increase in carcinoembryonic antigen secretion was observed upon treatment with proglumide and benzotript in three cell lines examined. Half-maximal inhibition of labeled gastrin binding was observed at concentrations of 0.4 mM benzotript and 8.6 mM proglumide. In addition, antigastrin antiserum added to HCT 116 cells adapted to growth in serum-free medium resulted in a concentration-dependent inhibition of cellular proliferation. These data suggest that gastrin may function as an autocrine growth factor in colon carcinoma.

Atenolol and chlorthalidone therapy for hypertension: a double-blind comparison.

In a randomized, double-blind, parallel-group study of 31 patients with mild to moderate hypertension, we compared a placebo regimen with a regimen of atenolol and chlorthalidone (Tenoretic). The study, which lasted seven weeks, began with a single-blind two-week placebo lead-in period, followed by a four-week double-blind treatment phase, and concluded with a one-week single-blind placebo washout period. Of 24 patients included in the analysis of efficacy, seven received one Tenoretic 50 tablet per day (atenolol, 50 mg; chlorthalidone, 25 mg), nine received one Tenoretic 100 tablet per day (atenolol, 100 mg; chlorthalidone, 25 mg), and eight received placebo. Supine systolic/diastolic blood pressure (mean +/- SD) decreased from 154 +/- 15.2/102 +/- 4.6 mm Hg during the baseline period to 128 +/- 8.5/85 +/- 4.0 mm Hg during treatment in the group receiving Tenoretic 100, from 153 +/- 12.6/104 +/- 5.4 mm Hg to 137 +/- 4.5/91 +/- 4.4 mm Hg in the group receiving Tenoretic 50, and from 150 +/- 11.9/101 +/- 1.6 mm Hg to 145 +/- 11.6/93 +/- 5.1 mm Hg in the group receiving placebo. Reductions in systolic and diastolic blood pressures in the active treatment groups were significantly greater than the pressure reductions in the group receiving placebo (P less than .05 to .1). The combination of atenolol and chlorthalidone was well tolerated, and in no case was treatment discontinued because of side effects. This study showed that one tablet per day of either Tenoretic 50 or Tenoretic 100 is effective and well tolerated in the treatment of mild to moderate hypertension.

A sensitive immunochemical assay for biologically active MuIFN-gamma.

An immunochemical assay for the detection of mouse gamma interferon (MuIFN-gamma) has been established. Using a purified monoclonal antibody (MAb) that neutralizes the antiviral activity of MuIFN-gamma, and a polyclonal antibody (PAb) prepared against affinity-purified MuIFN-gamma, we have developed a double-sandwich enzyme-linked immunosorbent assay (ELISA). The assay is specific for both natural and recombinant MuIFN-gamma and displays only background activity against MuIFN-alpha + beta, recombinant TNF (rTNF), human gamma interferon (HuIFN-gamma) and crude rat spleen cell supernatants. The assay is more sensitive and reproducible than the measurement of hydrogen peroxide (H2O2) release by macrophages, and is capable of detecting both crude and purified MuIFN-gamma down to 0.03 U/ml of antiviral activity, making this assay 10-100 times more sensitive than the conventional antiviral assay. The ELISA detects only biologically active MuIFN-gamma since treatment of the MuIFN-gamma at high temperature or low pH conditions resulted in abolishment of biological activity, as determined by inhibition of cytopathic effect, coincident with a dramatic decrease in ELISA titer.

Biochemical analysis and biological activities of immunoaffinity purified natural murine gamma interferon (MuIFN-gamma).

A rapid one-step procedure for the purification of natural murine gamma interferon (MuIFN-gamma) by immunoaffinity chromatography has been developed. Crude MuIFN-gamma was passed through a column containing immobilized anti-MuIFN-gamma monoclonal antibody, and the column was washed with high salt and detergent. Active MuIFN-gamma was subsequently eluted with ammonium thiocyanate/glycerol (yields of 20-40%). Analysis of the immunopurified interferon by sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions revealed biologically active bands of about 19.5, and 14 kd. Under nonreducing conditions, three active bands at 35, 19.5, and 14 kd could be seen. Gel filtration of the immunopurified MuIFN-gamma under reducing or nonreducing conditions showed a single major peak of antiviral activity corresponding to a molecular weight of 43 kd. The protein eluted from each band from the SDS-gel, in addition to possessing antiviral activity, was shown to activate macrophages in three assays: macrophage tumoricidal activity, hydrogen peroxide secretion, and expression of la antigen on the surface of exudate macrophages.

Clinical evaluation of a new temporary atrial pacing catheter: results in 100 patients.

Absence of a temporary atrial electrode that is stable and easily positioned has limited the use of atrial pacing in the hospital setting. A novel electrode involving a performed, 6F "J"-shaped catheter with a 10F anodal sphere and proximal fixed orienting wings 28 cm from the anodal tip was constructed. This design facilitated percutaneous insertion into the subclavian vein and positioning without fluoroscopy. Over a 15-month period, five physicians used the device in 100 patients for control of bradycardia in 56, overdrive suppression of atrial or ventricular tachyarrhythmias in 29, conversion and control of paroxysmal atrial tachycardia in seven, and temporary atrial-ventricular sequential pacing in eight patients with complete heart block. In 75 patients the electrode was inserted at the bedside without the benefit of fluoroscopy. Average insertion time was 2.5 minutes, initial thresholds were good, and lead stability evaluated by x-ray films and ECG recordings was excellent. The duration of pacing with the lead was 4.3 days (mean) and ranged from 1 to 23 days, with episodes of capture failure in only seven cases. Two of these cases were readily corrected by repositioning. This new electrode system could be rapidly inserted with excellent stability and reliability for days. Its ease of use could expand the role of temporary atrial pacing.

Pacemaker-mediated tachycardias: a rapid bedside technique for induction and observation.

The DDD pacemaker allows sensing and pacing in both chambers and can, therefore, maintain atrioventricular synchrony. However, this pacemaker creates an additional anterograde conduction system between the atrium and ventricle and, in the presence of ventriculoatrial (VA) conduction, the possibility of pacemaker-mediated tachycardia exists. A simple bedside technique that does not require catheterization or expensive equipment was used to detect VA conduction. Just after DDD pacer implantation, an attempt was made to detect VA conduction in 31 patients. Ambulatory monitoring (Holter) was done for 24 hours after implantation and at 2 to 4 and 6 to 8 weeks after implantation to detect pacemaker-mediated tachycardia. Attempts to induce pacemaker-mediated tachycardia were made using a special programmable external stimulator at follow-up after implantation. It was found that (1) all the 17 patients with detectable VA conduction had pacemaker-mediated tachycardia when the atrial refractory period was less than the VA conduction time, (2) pacemaker-mediated tachycardias were not inducible or detected spontaneously when atrial refractory period was equal to or greater than VA conduction time + 50 ms, (3) VA conduction was not detectable in 9 of the 17 patients at a later visit. Six of these 9 received antiarrhythmic therapy or had developed congestive heart failure. VA conduction has important implications in patients with DDD pacemakers and can be readily evaluated at the bedside.

Ergonovine-induced esophageal spasm in patients with chest pain resembling angina pectoris.

We studied the effect of ergonovine maleate (EM) on esophageal motor activity in 18 consecutive patients with angina-like chest pain. Significant coronary artery disease was excluded in each patient by cardiac catheterization studies. Baseline esophageal motility was abnormal in 12 patients (66%). After injection of EM, ten patients developed their typical chest pain at the onset of repetitive contractions. Thus, chest pain and esophageal dysfunction were clearly linked. Compared with saline injection, only the repetitive contractions were significantly increased after AM in these patients (P less than 0.01). Amplitude and duration of contractions were increased after EM, but not significantly. Due to potentially serious adverse effects, however, EM cannot be recommended for routine use as a provocative agent.