Flow velocity and predictors of a suboptimal coronary flow velocity reserve after coronary balloon angioplasty

AIMS

This study was conducted to analyse flow velocity parameters and predictors of a suboptimal coronary flow reserve (<2.5) following balloon angioplasty.

METHODS

Two hundred and twenty-five patients underwent sequential intracoronary Doppler as part of the DEBATE I study. Of these, 183, with complete angiography and Doppler at the 6-month follow-up, were included. Univariate and multivariate logistic analysis was performed to identify independent predictors of post-procedural suboptimal coronary flow reserve, defined as coronary flow reserve <2.5.

RESULTS

Forty-eight per cent (n=88) of the patients achieved a suboptimal coronary flow reserve. These patients had higher baseline velocities (cm.s(-1)) before balloon angioplasty (18+/-9 vs 14+/-6, P=0.004), after balloon angioplasty (22+/-11 vs 14+/-5, P<0.001) and at follow-up (19+/-9 vs 16+/-6, P=0.011) than the optimal coronary flow reserve group. Although the suboptimal group had lower hyperaemic velocities (cm.s(-1)) after balloon angioplasty than the optimal group (42+/-17 vs 49+/-16, P=0.008), these velocities became similar at follow-up. Increasing age (odds ratio, OR 1.071, P=0.0002), female gender (OR 2.52, P=0.014) and increasing pre-procedural baseline average peak velocities (OR 1.056, P<0.001) were found to be independent predictors of a suboptimal coronary flow reserve following balloon angioplasty.

CONCLUSION

A suboptimal coronary flow reserve was associated with (1) a chronically elevated baseline average peak velocity (2) a transient deficit in the hyperaemic average peak velocity (3) the elderly, and female gender.

In vitro study of FFR, QCA, and IVUS for the assessment of optimal stent deployment

We tested whether fractional flow reserve (FFR) discriminates between suboptimally and optimally deployed stents. Latex tubes (diameter solidus in circle = 4 mm) with diameter stenosis 40% (n = 3), 50% (n = 3) and 60% (n = 3) were tested in a pulsatile flow system, using water. Measurements were done at baseline (n = 9; FFR/QCA) and after suboptimal (SOD; 3-mm balloon at 8 atm) and optimal (OD; 4 mm balloon at 16 atm) deployment of a 35-mm stent (n = 6; FFR/QCA/IVUS). Varying Q from 150 to 50 ml/min increased FFR by 2-7%. Conversely, at 100 ml/min, FFR increased by only 0.8% from SOD to OD (P < 0.05). Extrapolating data to blood flow, the gain in FFR from SOD to OD is less than 5% for Q = 100 ml/min, while FFR may increase by 15-20% by changes in blood flow from 50 to 150 ml/min. We conclude that IVUS and QCA are more appropriate for the assessment of optimal stent deployment.

Rhabdomyolysis, acute renal failure, and death after monensin ingestion

We report a case of human monensin intoxication; to our knowledge, this is the first reported case in the medical literature. The patient took a dose of monensin three times higher than a dose considered lethal for cattle and developed a clinical picture similar to that reported in veterinary medicine. There was an early and extremely severe rhabdomyolysis followed by acute renal failure, heart failure, and death. The main changes observed at autopsy were extensive skeletal muscle necrosis, complement deposition at the myocardial level, pulmonary edema, and acute tubular damage.

Application of strengths, weaknesses, opportunities and threats analysis in the development of a health technology assessment program

There has been recent interest in developing a health technology assessment (HTA) function in Estonia. A group of individuals knowledgeable about HTA in Canada, Germany, Romania and Spain, along with representatives of the University of Tartu, Estonia, was convened by the Institute of Health Economics in Edmonton, Canada, to consider options for such a function. In a one-day workshop strengths, weaknesses, opportunities and threats (SWOT) analyses of HTA were conducted, first at a 'global' level, and then of the Estonian situation. The 'global' SWOT analysis yielded a large number of items that pertain to institutionalized HTA in a generic sense, i.e. not based on any individual HTA agency. The 'Estonian' SWOT yielded a subset of items, which pertain to development of HTA in that country. Ten actionable steps were then developed on the basis of this subset, which could be used to initiate the creation of an HTA body in Estonia.

[Socio-economic costs of road traffic accidents in the Canary Islands, Spain, in 1997]

OBJECTIVE

To evaluate the economic impact in terms of direct and indirect costs road traffic accidents in Canarias Islands (Spain) in 1997.

METHOD

The cost-of-illness method was used. Direct and indirect costs were estimated using prevalence cost, i.e., the costs produced in 1997. Direct costs were divided into health services costs, insurance administration costs and the costs of material damage to the vehicles. Indirect costs were obtained through transformation of physical units into monetary units using the approach of human capital theory.

RESULTS

The total cost of road traffic accidents was 39,887.16 million pesetas, equivalent to 24,470 for each inhabitant of the Canary Islands and representing 1.3% of the GNP in this region. The total direct cost was 32,559.67 million pesetas, constituting 82% of the total, which was distributed according to the different concepts analyzed: health service costs: 2,407.40 million pesetas; insurance administration costs, 13,415.89 million pesetas and the costs of material damages to the vehicles: 16,736.38 million pesetas. The total indirect costs was 7,327.49 million pesetas, accounting for 18% of the total costs, which was distributed in premature mortality (6,884.88 million pesetas) and absenteeism from work (442.61 million pesetas).

CONCLUSIONS

Although this study adopts a conservative approach by omitting costs associated with pain and suffering, permanent disability, and those of at-home care provided by the family, the hight socio-economic cost of road traffic accidents clearly indicates the need for the different administrations of the Canary Islands to collaborate in implementing preventive measures.

Hernia surgery for the third millennium. Does classical herniorraphy still play a role?

The steadily increasing use of prosthetic grafts in hernia repairs can be said to play down the classical approach for repairing groin hernia. We retrospectively report on 894 patients operated on for groin hernia at our out-patient surgery clinic from June 1992 to May 1998. Herniorraphy was widely performed (96.3%). The recurrence rate was of 1.6% (overall). For patients younger than 45 yr with no systemic concurrent disease, as few as 0.1% relapsed after a 58-month average follow-up. According to our results, ambulatory herniorraphy can provide an excellent degree of efficiency in selected young patients suffering from indirect unilateral primary groin hernia. Likewise, we regard the prosthetic repair as the gold standard technique in those patients with a weakened posterior inguinal wall.

[Beneficial effect of AN69 membranes on anemia in hemodialyzed patients]

Biocompatible hemodialysis membranes induce a smaller inflammatory response in hemodialysis patients, and remove a larger amount of higher molecular weight retention products, then cellulose membranes. These phenomena could improve uremic anemia in hemodialysis patients. The objective was to evaluate the effects of biocompatible AN69 membranes on anemia in hemodialysis patients. Twenty-five stable patients undergoing hemodialysis with cuprophane membrane for more than 6 months were studied prospectively. These patients were stratified in 2 groups. Group I (GI): 14 patients switched over to a more biocompatible dialyzer (from cuprophan to AN69) and Group II (GII): 11 patients continued treatment with the same cuprophan membrane. The study lasted 5 months. Baseline hematocrit (%), ferritin (ng/mL), transferrin saturation (%), KTV, PCR (g/kg/day) and dose of erythropoietin (EPO) (UI/week) were measured and were revised monthly. Target hematocrit was 33%-35%. A significant increase of hematocrit became obvious after 2 months in GI without changes in dose of EPO and intensity of dialysis, meanwhile GII remains stable.

CONCLUSION

Hemodialysis using AN69 membranes increases hematocrit without modifying intensity of dialysis.

Enteric plexus and interstitial cells of Cajal: interrelationship in the stomach of Podarcis hispanica (Reptilia). An ultrastructural study

The ultrastructure organization of the stomach enteric plexus was examined in the lizard Podarcis hispanica. The ganglions of the myenteric plexus present a low number of nerve cell bodies with a peculiar nucleus, which occasionally establish direct contacts with cells of the circular muscle layer. Glial cells are smaller than the neurones, and their nucleus is very electron-dense. They surround the axons that constitute the fibres of the myenteric plexus. Four main types of axon profile are described in a morphological consideration of the vesicle population. In the interstice of the circular muscle layer we describe two types of interstitial cells that, due to their ultrastructural characteristics, may be equivalent to the interstitial cells of Cajal which have been described in mammalians. These cells shows parallel distribution to the stomach nerve plexuses, establishing close contacts with them through their long cytoplasmic prolongations. By means of small gap-like unions, they contact both each other and the smooth muscle cells near them. We describe a submucous plexus, where neuronal bodies are scattered among bundles of nervous fibres, some of which are myelinated. A mucous plexus with isolated neurones is located in the lamina propria. Axonal varicosities containing vesicles contact with the cells of the mucous. Interconnected interstitial cells may also be found in this plexus.

[Rhabdomyolysis and acute renal failure secondary to statins]

Statins are competitive inhibitors of hydroxy-methyl-glutaryl coenzyme A (HMG-CoA) reductase and are the most commonly used drugs to treat hyperlipidaemia. Muscle toxicity is an adverse effect reported with a low incidence and rarely associated with acute renal failure due to rhabdomyolysis. We describe two patients with chronic renal failure treated with pravastatin and simvastatin who suffered rhabdomyolysis and acute renal failure. One patient started pravastatin several days after cessation of bezafibrate and developed acute renal failure without needing dialysis. The other was treated with simvastatin three years ago and suffered rhabdomyolysis when renal function was impaired after indomethacin was prescribed for backache. He needed hemodialysis because of acute cardiac failure and died from a respiratory infection while on mechanical ventilation. Myopathy was reversible in both patients. We recommend starting statins with the lower doses in chronic renal failure and monitoring muscle enzymes when renal function changes or when new drugs with potential interactions are prescribed.

Indirect evidence for a role of a subpopulation of activated neutrophils in the remodelling process after percutaneous coronary intervention

AIM

Leukocytes have been implicated in restenosis following percutaneous transluminal coronary angioplasty. We investigated the link between the activated status of circulating neutrophils and restenosis after angioplasty.

METHODS AND RESULTS

The population of 108 patients with single, de novo lesions located in native coronary arteries were treated with elective balloon angioplasty (n=44) or stenting (n=64). Pre-, post-procedure and 6-month follow-up, angiograms were analysed by an independent core laboratory. Blood samples were collected immediately before treatment and the antigen CD66, which is specifically expressed by activated neutrophils, was measured. Overall, the average expression of CD66 was 6.4+/-3.6 of mean fluorescence intensity. In the stepwise linear regression model, which included biological, clinical and angiographic variables, absolute gain showed a direct association (P<0.001) with relative late loss (relative late loss=absolute late loss/pre-procedure reference diameter), whereas CD66 expression was inversely associated with relative late loss (P=0.004). CD66 expression also showed an inverse association with relative late loss in the balloon angioplasty treated patients (P=0.002, beta=-0.49). In the stent subgroup, only reference vessel diameter and acute gain were independent predictors of relative late loss.

CONCLUSION

Our results confirm the beneficial role of activated neutrophils pre-procedure in the restenotic process after balloon angioplasty. The lack of a relationship between CD66 expression by neutrophils and relative late loss after stenting suggests that this leukocyte may be involved in the remodelling process.

Acetylcholinesterase-positive and paraformaldehyde-induced-fluorescence-positive innervation in the upper eyelid of the sheep (Ovis aries)

This is the first study which describes the innervation of some eyelid structures, such as the glands of Moll and the glands of Zeiss. It is also the first to investigate the innervation pattern of the eyelid as a whole. We have studied the acetylcholinesterase-positive and paraformaldehyde-induced-fluorescence-positive (FIF+) innervation pattern of the different structures that constitute the upper eyelid of the sheep. There is widespread acetylcholinesterase-positive innervation in the epithelium, but not such an abundant FIF+ innervation. Both types of innervation are represented in the connective tissue by trunks or fibers that are distributed towards the different structures immersed within them. In the glands of Zeiss, cholinesterase-positive innervation is much more widespread than FIF innervation. On the contrary, the glands of Moll present denser FIF+ innervation than acetylcholinesterase-positive innervation. The Meibomian glands and the lachrymal glands show a rich acetylcholinesterase-positive and FIF+ innervation. Eyelid muscle innervation is mainly acetylcholinesterase-positive. In the conjunctive membrane there is no acetylcholinesterase-positive innervation, and only scarce FIF+ fibers can be demonstrated.

[Weaning from mechanical ventilation. The aim of nursing research]

Management of patients difficult to wean from the ventilator is a practical challenge in which professional nurses are deeply involved.The clinical research applied over the last years has tried to describe the characteristics of weaning phenomenon and the associated factors, to find predictive outcomes to guide clinical decisions, to search new strategies to conduct the protocols and to identify the most effective modes of weaning. In this paper a critical review of the current knowledge from a nursing perspective is done. The weaning conceptual model proposed by the American Association of Critical Care Nurses (AACN) group has been used as a theoretical framework.

Cytokine-driven inflammatory response is associated with the hypermetabolism of AIDS patients with opportunistic infections

BACKGROUND

To assess a possible role of systemic inflammation in the resting metabolic response in AIDS patients with active secondary infections.

METHODS

Fifty-two patients with AIDS-defined criteria and concomitant active infections and 19 healthy subjects were studied. Measurements were as follows: body composition assessed by bioelectrical impedance; resting energy expenditure (REE) by 30-minute indirect calorimetry; cytokine concentrations (IL-6, IFNalpha, TNFalpha, sTNF-R1) by ELISA; C-reactive protein (CRP), erythrocyte sedimentation rate, fibrinogen, and nutritional parameters by standard techniques.

RESULTS

REE adjusted for fat-free mass (REEFFM) was significantly increased in AIDS patients despite 39% of them not being hypermetabolic. The patients were undernourished and were found to have increased levels of acute-phase proteins and increased concentrations of IL-6 and sTNF-R1 relative to controls. REE parameters were positively related to CRP, ESR, ferritin, IL-6, and sTNF-R1 and negatively related to albumin, prealbumin, and transferrin. CRP was an independent predictor of REEFFM in AIDS patients and explained 25% of its variability. Patients with severe inflammation (CRP > or = 37 mg/dL) were significantly hypermetabolic with respect to patients without inflammation (CRP < 6 mg/dL) and had higher levels of IL-6 and sTNF-R1 and lower levels of albumin and prealbumin. Although no significant differences were observed with respect to the infection type, patients with tuberculosis and Pneumocystis carinii infections had higher resting metabolic and inflammatory responses, whereas patients with recurrent bacterial pneumonia were normometabolic and had lower levels of inflammatory markers.

CONCLUSIONS

Resting hypermetabolism observed in AIDS patients with concurrent active infections is related to the presence and severity of systemic cytokine-driven inflammatory response, which could reflect the type of secondary infection.

Three-dimensional intravascular ultrasound assessment of noninjured edges of beta-irradiated coronary segments

BACKGROUND

The "edge effect," late lumen loss at the margins of the treated segment, has become an important issue in the field of coronary brachytherapy. The aim of the present study was to assess the edge effect in noninjured margins adjacent to the irradiated segments after catheter-based intracoronary beta-irradiation.

METHODS AND RESULTS

Fifty-three vessels were assessed by means of 3-dimensional intravascular ultrasound after the procedure and at 6- to 8-month follow-up. Fourteen vessels (placebo group) did not receive radiation (sham source), whereas 39 vessels were irradiated. In the irradiated group, 48 edges (5 mm in length) were identified as noninjured, whereas 18 noninjured edges were selected in the placebo group. We compared the volumetric intravascular ultrasound measurements of the noninjured edges of the irradiated vessels with the fully irradiated nonstented segments (IRS, n=27) (26-mm segments received the prescribed 100% isodose) and the noninjured edges of the vessels of the placebo patients. The lumen decreased (6 mm(3)) in the noninjured edges of the irradiated vessels at follow-up (P:=0. 001). We observed a similar increase in plaque volume in all segments: noninjured edges of the irradiated group (19.6%), noninjured edges of the placebo group (21.5%), and IRS (21.0%). The total vessel volume increased in the IRS in the 3 groups. No edge segment was subject to repeat revascularization.

CONCLUSIONS

The edge effect occurs in the noninjured margins of radiation source train in both irradiated and placebo patients. Thus, low-dose radiation may not play an important role in this phenomenon, whereas nonmeasurable device injury may be considered a plausible alternative explanation.

Nitrovasodilators, low-dose aspirin, other nonsteroidal antiinflammatory drugs, and the risk of upper gastrointestinal bleeding

BACKGROUND The relation between medications that release nitric oxide, such as nitroglycerin and other nitrovasodilators, and upper gastrointestinal bleeding is uncertain. In animals, these medications reduce the gastric damage induced by nonsteroidal antiinflammatory drugs. Nitric oxide, however, inhibits platelet aggregation and may contribute to bleeding from an ulcer.

METHODS

We performed a case-control study to determine the risk of bleeding in patients taking nitrovasodilators, low-dose aspirin, or other nonsteroidal antiinflammatory drugs. The case group was made up of 1122 consecutive patients admitted to one of four hospitals with bleeding from a peptic lesion. The 2231 control subjects were 1109 patients hospitalized for other reasons and 1122 outpatients from the same geographic area.

RESULTS

In the week before admission, 520 (46.3 percent) of the patients with bleeding had taken a nonsteroidal antiinflammatory drug other than low-dose aspirin, 120 (10.7 percent) had taken low-dose aspirin (< or = 300 mg per day), 60 (5.3 percent) a nitrovasodilator, and 135 (12.0 percent) an antisecretory agent such as a histamine H2-receptor antagonist or a proton-pump inhibitor. In multivariate models that adjusted for age, sex, and clinical risk factors, the use of a nonsteroidal antiinflammatory drug other than low-dose aspirin was independently associated with an increased risk of bleeding from a peptic ulcer (odds ratio, 7.4; 95 percent confidence interval, 4.5 to 12.0), as was the use of low-dose aspirin alone (odds ratio, 2.4; 95 percent confidence interval, 1.8 to 3.3). The use of a nitrovasodilator was associated with a decreased risk of bleeding (odds ratio, 0.6; 95 percent confidence interval, 0.4 to 0.9), as was antisecretory therapy (odds ratio, 0.6; 95 percent confidence interval, 0.4 to 0.8). In patients taking any type of nonsteroidai antiinflammatory drug, the use of a nitrovasodilator or antisecretory therapy was independently associated with a decreased risk of bleeding.

CONCLUSIONS

The use of nitrovasodilator drugs is independently associated with a decreased risk of upper gastrointestinal bleeding.

[Intravascular ultrasound in cardiology]

Intravascular ultrasound (IVUS) is a clinically useful tool that provides cross-sectional images of the coronary arterial lumen and wall. Diagnostic applications of IVUS include the evaluation of ambiguous lesions on angiography particularly at the bifurcations. IVUS is also useful in the assessment of coronary vasculopathy in cardiac transplant patients or it can help to diagnose abnormalities such as syndrome X or coronary artery spasm. IVUS can optimize the performing of percutaneous coronary interventions, especially stent implantation. It represents as well an optimal tool for assessing regression of atherosclerosis. Three-dimensional reconstruction, elastography and imaging guide wires are some of the recent advances in the field of intravascular ultrasound.

[A comparison of phosphorus-chelating effect of calcium carbonate versus calcium acetate before dialysis]

INTRODUCTION

The hyperphosphatemia, hypocalcemia and low calcitriol levels are pathogenic factors for secondary hyperparathyroidism in chronic renal failure. The phosphorus control is essential to prevent secondary hyperparathyroidism. There are not comparatives studies to test the efficacy of control of phosphorus binders in predialysis patients.

AIM

To compare the efficacy of calcium carbonate vs calcium acetate as phosphate binder in predialysis patients.

MATERIAL AND METHODS

The present study includes 28 patients with chronic renal failure (mean clearance of creatinine 21 ml/min). Patients were separated into two groups: Group 1: (n = 14) received calcium carbonate 2,500 mg/day (1,000 mg of calcium); Group 2: (n = 14) receives calcium acetate 1,000 mg (254 mg of calcium). Calcium and phosphorus were determined every 4 months; i-PTH, alkaline phosphatase and clearance of creatinine were determined every six months.

RESULTS

Both groups were comparable regarding age, renal function, calcium, phosphorus, alkaline phosphatase and i-PTH on basal situation and the end of study were not different. The serum calcium increased, not significantly, in the calcium carbonate group (group 1) [from 9.2 to 9.8 mg/dl (p = 0.05)], however it was not modified in the calcium acetate group (group 2). The serum phosphorus decreased significantly (p < 0.05) in both groups, independently of the calcium levels. Alkaline phosphatase and i-PTH not was modified during the study period.

CONCLUSIONS

1) Both calcium carbonate and calcium acetate are similarly effective as phosphate binder. 2) The carbonate group required four fold greater doses of calcium that acetate group. 3) The calcium acetate has less hypercalcemic effect than calcium carbonate.

Enhanced learning after genetic overexpression of a brain growth protein

Ramón y Cajal proposed 100 years ago that memory formation requires the growth of nerve cell processes. One-half century later, Hebb suggested that growth of presynaptic axons and postsynaptic dendrites consequent to coactivity in these synaptic elements was essential for such information storage. In the past 25 years, candidate growth genes have been implicated in learning processes, but it has not been demonstrated that they in fact enhance them. Here, we show that genetic overexpression of the growth-associated protein GAP-43, the axonal protein kinase C substrate, dramatically enhanced learning and long-term potentiation in transgenic mice. If the overexpressed GAP-43 was mutated by a Ser --> Ala substitution to preclude its phosphorylation by protein kinase C, then no learning enhancement was found. These findings provide evidence that a growth-related gene regulates learning and memory and suggest an unheralded target, the GAP-43 phosphorylation site, for enhancing cognitive ability.

Distinct NMDA receptor subpopulations contribute to long-term potentiation and long-term depression induction

Long-term potentiation (LTP) and long-term depression (LTD) are persistent modifications of synaptic strength that have been implicated in learning, memory, and neuronal development. Despite their opposing effects, both forms of plasticity can be triggered by the activation of NMDA receptors. One mechanism proposed for this bidirectional response is that the specific patterns of afferent stimulation producing LTP and LTD activate to different degrees a uniform receptor population. A second possibility is that these patterns activate separate receptor subpopulations composed of different NMDA receptor (NR) subunits. To test this hypothesis we examined the inhibition of LTP and LTD by a series of competitive NMDA receptor antagonists that varied in their affinities for NR2A/B and NR2C/D subunits. The potency for the inhibition of LTP compared with inhibition of LTD varied widely among the agents. Antagonists with higher affinity for NR2A/B subunits relative to NRC/D subunits showed more potent inhibition of LTP than of LTD. D-3-(2-carboxypiperazine-4-yl)-1-propenyl-1-phosphonic acid, which binds to NR2A/B with very high affinity relative to NR2C/D, showed an approximately 1000-fold higher potency for LTP than for LTD. These results show that distinct subpopulations of NMDA receptors characterized by different NR2 subunits contribute to the induction mechanisms of potentiation and depression.

Geographic miss: a cause of treatment failure in radio-oncology applied to intracoronary radiation therapy

BACKGROUND

A recognized limitation of endovascular beta-radiation therapy is the development of new stenosis at the edges of the irradiated area. The combination of injury and low-dose radiation may be the precursor of this phenomenon. We translated the radio-oncological concept of "geographic miss" to define cases in which the radiation source did not fully cover the injured area. The aims of the study were to determine the incidence and causes of geographic miss and evaluate the impact of this inadequate treatment on the outcome of patients treated with intracoronary beta-radiation.

METHODS AND RESULTS

We analyzed 50 consecutive patients treated with beta-radiation after percutaneous coronary intervention. The prescribed dose ranged between 12 and 20 Gy at 2 mm from the source axis. By means of quantitative coronary angiography, the irradiated segment (IRS) and both edges were studied before and after intervention and at 6-month follow-up. Edges that were injured during the procedure constituted the geographic miss edges. Twenty-two edges were injured during the intervention, mainly because of procedural complications that extended the treatment beyond the margins of the IRS. Late loss was significantly higher in geographic miss edges than in IRSs and uninjured edges (0.84+/-0.6 versus 0.15+/-0.4 and 0.09+/-0.4 mm, respectively; P<0.0001). Similarly, restenosis rate was significantly higher in the injured edges (10% within IRS, 40.9% in geographic miss edges, and 1.9% in uninjured edges; P<0.001).

CONCLUSIONS

These data support the hypothesis that the combination of injury and low-dose beta-radiation induces deleterious outcome.

Saphenous vein graft disease treated with the Wiktor Hepamed stent: procedural outcome, in-hospital complications and six-month angiographic follow-up

OBJECTIVES

To evaluate the effectiveness of electively placed heparin-coated stents in the treatment of coronary saphenous vein bypass grafts with de novo lesions less than 15 mm in diameter in a prospective study with all eligible consecutive patients presenting to Middelheim Hospital, Antwerp, Belgium between September 1997 and August 1998.

PATIENTS AND METHODS

Fifty patients with 53 lesions were studied. Anginal class, risk factors, quantitative coronary angiographic measurements pre- and postprocedure, procedural outcome, in-hospital events, clinical status on discharge, and six-month clinical and angiographic follow-up (in 48 patients) were recorded. All patients received acetylsalicylic acid and ticlopidine, unless known intolerance was present.

RESULTS

On average, 1.1 stents/patient were placed in very old saphenous vein grafts (11. 7+/-3.9 years). Procedural success was 98%. Only two non-Q wave myocardial infarctions (MIs) occurred, with no Q-wave MIs and no deaths during hospital stay. Length of hospital stay was short (2. 4+/-1.7 days), and 96% of patients were free of angina on discharge. At six-months' follow-up, two patients had died, one of whom died of a noncardiac cause. One patient suffered a non-Q wave MI. At six months, 86% of patients were free from angina. Minimal luminal diameter decreased from 1.14 mm before to 3.33 mm after stenting and to 2.52 mm at six months. Restenosis was present in 22% of patients (21.6% of lesions).

CONCLUSIONS

In a selected population with coronary saphenous vein bypass graft disease, Wiktor heparin-coated stents can be delivered with an excellent periprocedural outcome. Six-month outcome appears favourable with a low recurrence of angina (18%) and a low rate of angiographic restenosis (21.6%).

Vineberg revisited. Long-term survival more than two decades after direct surgical myocardial revascularization

A 65-year old patient was referred to our institution for a diagnostic catheterization. 23 years before, a direct surgical myocardial procedure using the Vineberg technique was performed. Currently, the angiogram shows patent left and right internal mammary arteries implanted directly into the myocardium and connecting with the native circulation through collaterals. As the native coronary artery tree shows very severe three vessel disease, it is hypothesized that the major contribution of myocardial perfusion comes from the implanted vessels. This is the first case to show a long-term success of the Vineberg operation, with persistence of myocardial perfusion through newly formed vasculature.

The effect of 32P beta-radiotherapy on both vessel remodeling and neointimal hyperplasia after coronary balloon angioplasty and stenting: a three-dimensional intravascular ultrasound investigation

Intracoronary radiation is a promising therapy to decrease restenosis after percutaneous intervention. The aim of this pilot study was to determine the mechanism of intracoronary beta-radiation after balloon angioplasty and stenting in a double-blind placebo-controlled randomized fashion. Twenty-six patients were randomized to either placebo (n = 6) or 3 doses (28, 35 and 42 Gy) of beta-radiation (n = 20) using the Guidant brachytherapy system (27 mm long 32P source wire). Of these, 21 patients underwent post-procedure and 6-month follow-up three-dimensional intravascular ultrasound (IVUS) assessment. Volumetric quantification was performed by means of a semi-automated contour detection system after an ECG-gated motorized pullback IVUS imaging and three-dimensional reconstruction. We compared the volumetric changes (Delta) of total vessel volume (TVV), plaque volume (PV) and lumen volume (LV) after 6 months between placebo (dummy wire) and irradiated patients. In addition, the volume of neointimal hyperplasia was quantified within the stented segments. There was an opposite behavior of TVV and LV change between placebo (DeltaTVV = -24 mm3 and DeltaLV = -42 mm3) and irradiated (DeltaTVV = +18 mm3 and (DeltaLV = +5 mm3) patients. The mean neointimal formation within the stented segment in the irradiated patients (n = 7) was 1.9 mm3 (1.5%). Our results suggest that beta-radiation affects vessel remodeling after percutaneous intervention and inhibit neointimal formation in stented patients.

Three-dimensional intravascular ultrasonic volumetric quantification of stent recoil and neointimal formation of two new generation tubular stents

Currently, several different designs of coronary stents are available. However, only a few of the new generation stents have been investigated in large randomized trials. Mechanical behavior of first-generation stents (Palmaz-Schatz, Gianturco-Roubin) may not be applied to the new designs. We investigated the chronic mechanical behavior (recoil) of 2 stents recently approved by the Food and Drug Administration (MULTILINK and NIR). Forty-eight patients with single-stent implantation (23 MULTILINK and 25 NIR) were assessed by means of volumetric 3-dimensional intravascular ultrasound analysis after the procedure and at 6-month follow-up. In addition, volumetric assessment of neointimal formation was performed. No significant chronic stent recoil was detected in both groups (delta MULTILINK stent volume: +5.6+/-41 mm3 [p = NS] and delta NIR stent volume + 2.1+/-26 mm3 [p = NS]). A similar degree of neointimal formation at 6 months was observed between the 2 stents (MULTILINK 46+/-31.9 mm3 vs NIR 39.9+/-27.6 mm3, p = NS). In conclusion, these 2 second-generation tubular stents did not show chronic recoil and appeared to promote similar proliferative response after implantation in human coronary arteries.

Coronary bifurcation stenting using dedicated bifurcation stents

We report three cases of successful implantation of three different stents specially designed for bifurcation lesions, guided by intracoronary ultrasound. The BARD and AVE are true bifurcated stents for side-branch access and the NIR-Side Royal is a single modified NIR stent with an aperture to allow provisional bifurcation stenting. These designs introduce a new era in percutaneous management of coronary bifurcation lesions. Cathet. Cardiovasc. Intervent. 49:105-111, 2000.

Late stent malapposition occurring after intracoronary beta-irradiation detected by intravascular ultrasound

We report a case of late stent malapposition occurring 6 months after intracoronary beta-irradiation detected by three-dimensional intravascular ultrasound, in spite of good apposition immediately after the procedure. Volumetric quantification revealed that stent volume remained unchanged, whereas total vessel volume increased by 13% after 6 months within the stent area. The increase of the vessel volume took place mainly in the proximal part of the stent, where the malapposition was located.

Randomized trial of weekly sulfadoxine/pyrimethamine vs. daily low-dose trimethoprim-sulfamethoxazole for the prophylaxis of Pneumocystis carinii pneumonia after liver transplantation

We conducted a prospective, randomized clinical trial among liver transplant patients to assess the efficacy and safety of weekly sulfadoxine/pyrimethamine compared with daily trimethoprim-sulfamethoxazole in the prevention of Pneumocystis carinii pneumonia. The studied drugs were given during 6 months after transplantation. One hundred twenty patients were included. None of the 60 patients receiving weekly sulfadoxine/pyrimethamine developed Pneumocystis carinii pneumonia, whereas two cases (3%) developed among the 60 patients who received trimethoprim-sulfamethoxazole. For both patients, the studied medication had been discontinued several weeks earlier because of adverse effects. No differences were observed in the incidence of adverse effects. We conclude that weekly sulfadoxine/pyrimethamine is as effective and safe as is daily trimethoprim-sulfamethoxazole in the prophylaxis of Pneumocystis carinii pneumonia after liver transplantation.

[Genotype-phenotype correlation in myotonic dystrophy and prediction of clinical seriousness]

INTRODUCTION

Since description of the expansion of the number of CTG trinucleotides on the long arm of chromosome 19 in the 19 q 13.2-13.3 interval as being responsible for myotonic dystrophy (DM), many studies have established a direct relationship between the size of the expansion and the severity of the manifestations.

OBJECTIVES

To evaluate the clinico-genetic correlation in a population with DM in Eastern Andalucia and to establish the predictive value of the increase in number of CTG repetitions with regard to clinical gravity.

PATIENTS AND METHODS

A transverse study of persons from families known to have members with DM, classified with regard to the clinical gravity of their illness. Diagnosis was by means of clinical neurological, ophthalmological and neurophysiological examination and subsequently by genetico-molecular study, Southern blot, PCR, oligonucleotide CTC hybridization and Northern blot.

RESULTS

Genetic studies confirmed the previous clinical diagnosis of DM in 78 persons, of the 145 studied, who came from 32 families. The average size of the mutation was 1-5 kb. There was close correlation between the size of the expansion and the clinical condition. Logistic repression studies permitted adequate classification in function of the size of the expansion in 87.23% of the cases of clinically relevant illness and in 90% of the cases in which the condition was not clinically relevant.

CONCLUSIONS

There is a strong association between the clinical features of DM and the magnitude of the mutation. The size of the expansion has considerable predictive value in prognosis of the disorder. This may be useful when making decisions during prenatal diagnosis.

Compassionate use of intracoronary beta-irradiation for treatment of recurrent in-stent restenosis

Recurrent in-stent restenosis after balloon angioplasty poses a serious management problem. Previously g-radiation has been shown to be effective in patients with in-stent restenosis. The aim of the study was to determine the feasibility and safety of b-radiation in patients with recurrent in-stent restenosis. From May 1997 to December 1998, 18 patients were treated with balloon angioplasty (n = 8) or laser (n = 10), followed by intracoronary b-radiation at a prescribed dose of 16 Gray at 2 mm from the source, for reference diameters by quantitative coronary angiography < 3.25 mm or 20 Gray for reference diameters > or =3.25 mm. Vessels treated were as follows: left anterior descending: (n = 5); circumflex: (n = 4); right coronary artery: (n = 6); saphenous vein graft: (n = 3). Average recurrence rate was 2.4 +/- 0.7 and the restenotic length was 16 +/- 7 mm. b-radiation was successfully delivered in all patients. Two patients presented complications related to laser debulking: a non-Q wave myocardial infarction in one and a re-angioplasty due to uncovered distal dissection in another. Geographical miss, defined as an area which has been injured but not covered by the radiation source, was demonstrated in 8 patients. Seventeen patients (94%) completed the 6-month angiographic follow-up. Restenosis (> 50% Diameter Stenosis) was observed in 9 patients (53%), leading to target lesion revascularization in 8 patients (47%). Six of the 9 restenoses were located in areas with geographical miss. Intracoronary b-radiation for recurrent in-stent restenosis appears to be a safe and feasible management strategy. However, the mismatch between injured and irradiated area may lead to failure of this therapy.

Late coronary occlusion after intracoronary brachytherapy

BACKGROUND

Intracoronary brachytherapy appears to be a promising technology to prevent restenosis. Presently, limited data are available regarding the late safety of this therapeutic modality. The aim of the study was to determine the incidence of late (>1 month) thrombosis after PTCA and radiotherapy.

METHODS AND RESULTS

From April 1997 to March 1999, we successfully treated 108 patients with PTCA followed by intracoronary beta-radiation. Ninety-one patients have completed at least 2 months of clinical follow-up. Of these patients, 6.6% (6 patients) presented with sudden thrombotic events confirmed by angiography 2 to 15 months after intervention (2 balloon angioplasty and 4 stent). Some factors (overlapping stents, unhealed dissection) may have triggered the thrombosis process, but the timing of the event is extremely unusual. Therefore, the effect of radiation on delaying the healing process and maintaining a thrombogenic coronary surface is proposed as the most plausible mechanism to explain such late events.

CONCLUSIONS

Late and sudden thrombosis after PTCA followed by intracoronary radiotherapy is a new phenomenon in interventional cardiology.

Particulate and ozone pollutant effects on the respiratory function of children in southwest Mexico City

We assessed the contributions of particulate matter with aerodynamic diameters < or =10 and < or =2.5 microm (PM2.5 and PM10) and ozone (O3) to peak expiratory flow (PEF) and respiratory symptoms in 40 schoolchildren 8-11 years of age for 59 days during three periods in 1991 at a school in southwest Mexico City. We measured peak expiratory flow in the morning on the children's arrival at school and in the afternoon before their departure from school. Separately for morning and afternoon, we normalized each child's daily measurement of peak flow by subtracting his or her mean peak flow from the daily measurement. Child-specific deviations were averaged to obtain a morning and afternoon mean deviation (APEF) for each day. Mean 24-hour O3 level was 52 parts per billion (ppb; maximum 103 ppb); mean 24-hour PM2.5 and PM10 were 30 microg/m3 (maximum 69 microg/m3) and 49 microg/m3 (maximum 87 microg/m3), respectively. We adjusted moving average and polynomial distributed lag multiple regression analyses of APEF vs pollution for minimum daily temperature, trend, and season. We examined effects of PM2.5, PM10, and O3, on deltaPEF separately and in joint models. The models indicated a role for both particles and O3 in the reduction of peak expiratory flow, with shorter lags between exposure and reduction in peak expiratory flow for O3 than for particle exposure (0-4 vs 4-7 days). The joint effect of 7 days of exposure to the interquartile range of PM2.5 (17 microg/m3) and O3 (25 ppb) predicted a 7.1% (95% confidence interval = 11.0-3.9) reduction in morning peak expiratory flow. Pollutant exposure also predicted higher rates of phlegm; colinearity between pollutants limited the potential to distinguish the relative contribution of individual pollutants. In an area with chronically high ambient O3 levels, school children responded with reduced lung function to both O3 and particulate exposures within the previous 1 to 2 weeks.

Perianal disease of tuberculous origin: report of a case and review of the literature

PURPOSE

A case of anal tuberculosis in an otherwise asymptomatic patient with bleeding anal ulcers is presented. The clinical features of this entity and the problems in differential diagnosis between anal infectious vs. inflammatory diseases are discussed.

METHODS

The management and outcome of the case of an adult patient who presented with perianal ulcers is described.

RESULTS

On a three-drug antituberculous regimen, symptoms abated, radiographic infiltrates improved, and perianal ulcers healed.

CONCLUSION

Anal tuberculosis is an extremely rare disease. A tuberculous origin must be considered when the cause of perianal ulcers is unclear to avoid undesirable delays in the diagnosis and treatment of this disease.

Congenital diaphragmatic hernia: mortality determinants in a Hispanic population

OBJECTIVES

Determine which factors were associated with mortality in our patients, specifically whether ventilatory parameters and arterial blood gas could be used to predict outcome. The role of delaying surgery and the presence of contra lateral pneumothorax were also assessed.

BACKGROUND

Mortality among babies born with congenital diaphragmatic hernia remains high. The associated pulmonary hypoplasia and hypertension account for most of the overall mortality. There is no uniform consensus as to which parameters predict outcome.

METHOD

Study population consisted of thirty-two patients with CDH managed during a ten-year period. Retrospective data obtained included: perinatal data, postnatal complications, ventilatory parameter data, arterial blood gas, type and age of surgery. Ventilatory index, oxygenation index and arterial to alveolar oxygen difference (A-aDO2) within the first 24 hours of life and after surgical correction were compared among the 23 patients who underwent surgical correction. Timing of surgery and frequency of pneumothorax were compared between survivors and non-survivors. Epi-Info Software Package was used for statistic analysis.

RESULTS

Overall survival was 40%. Survival of surgically corrected infants was 61%. Non-survivors had significantly higher A-aDO2 than survivors (p < 0.05). No significant differences in pCO2, ventilatory index, or oxygenation index were identified between survivors and non survivors. Surgical repair performed after the first twenty-four hours of life, was associated with a higher survival rate (p < 0.05). Fourteen patients (39%) developed contralateral pneumothorax, eleven (79%) of these died.

CONCLUSIONS

(1) contralateral pneumothorax was associated with higher mortality, 2) A-aDO2 was a better prognostic indicator than pCO2, ventilatory index, or oxygenation index, 3) delaying surgical repair was associated with better survival rate.

Enteral nutrition by percutaneous endoscopic gastrojejunostomy in severe hyperemesis gravidarum: a report of two cases

We describe the first two cases in which percutaneous endoscopic gastrojejunostomy was used as a means to provide enteral nutrition in severe hypermesis gravidarum. The use of this method of enteral access provided an alternative to parenteral nutrition, was well tolerated, cost-effective and had no major complications. In both cases the nutritional goal for mothers as well as appropriate fetal growth and development were achieved.

Effects of nitrate and prophylactic aspirin on upper gastrointestinal bleeding: a retrospective case-control study

Experimental studies suggest that nitric-oxide releasing drugs reduce gastroduodenal damage induced by non-steroidal anti-inflammatory drugs, but it is not known whether these agents have this effect in humans. The aim of the present study was to evaluate the risk of upper gastrointestinal bleeding in patients who receive aspirin and nitrates for vascular occlusive diseases. This was a retrospective case-control study of 736 consecutive patients admitted with upper gastrointestinal bleeding, compared with 1472 age- and sex-matched hospital controls. Chronic low-dose aspirin regimens had been used by 12.6% of cases and 5.7% of controls, nitrates by 4.8% and 5.8%, and combined nitrates and low-dose aspirin by 2.7% and 1.9%, respectively. Logistic regression analysis identified low-dose aspirin use as an independent risk factor for gastrointestinal bleeding, whereas nitrate use was found to be a protective factor. The combination of both nitrate and low-dose aspirin was not associated with an increased risk of bleeding.

[Percutaneous endoscopic gastrostomy and gastrojejunostomy. Experience and its role in domiciliary enteral nutrition]

Percutaneous Endoscopic Gastrostomy (PEG) and its variation Percutaneous Endoscopic Gastrojejunostomy (PEGJ), has become the method of choice to achieve an enteral access route in patients who require long term enteral nutrition, especially in the area of the At Home Enteral Nutrition (AHEN). We present our experience on the first PEG's and PEGJ's carried out in our hospital.

MATERIAL

We studied 48 patients (14 women and 34 men) in whom a PEG/Percutaneous Endoscopic Gastrojejunostomy (PEGJ) was indicated, as they required enteral nutrition for prolonged periods of time (> 4 weeks) and/or they presented obstructive dysphagia, neuromotor dysphagia, or incorrigible vomiting in the two cases in whom PEGJ was carried out. 34 patients underwent the Ponsky-Gauderer technique, 6 patients underwent the Sacks-Vine technique, and 2 patients underwent a PEGJ. 24 hours after the PEGJ enteral nutrition (EN) was begun in a progressive manner. During the hospitalization period there was a daily follow up of the patient. In those cases in which At Home Enteral Nutrition was programmed, the patients/families were trained in the techniques and the care of the PEG and the EN, and the control was carried out through the Nutrition out patient department.

RESULTS

PEG was successfully carried out in 42 patients (88%). 35 patients had previously been given EN through a naso-gastric tube (NGT), while in 7 cases the PEG was the first enteral access route. The average duration of the PEG was 212 days, and 27 patients (64%) needed the PEG for more than 3 months. The mean caloric supply was 1921 +/- 200 kcal/day. The mode of administration was by means of an intermittent infusion by gravity in 31 cases, and by continuous infusion using a volumetric pump in 11 patients. Two patients with pregnancy induced hyperemesis underwent a PEGJ in the 3rd and the 4th month of pregnancy, with the pregnancy being successfully brought to term and ending in vaginal deliveries. Carrying out a PEG permitted release from hospital and the programming of At Home Enteral Nutrition in 30 patients. With respect to the evolution of the patients, 22 patients have died during the course of the study. 18 patients remain in follow up in an ambulatory Enteral Nutrition program, and in the two patients with pregnancy induced hyperemesis, the PEGJ was removed after the pregnancy was successfully ended. There were no complications of any kind in 21 patients. The most common complication was the infection of the gastrostomy, which occurred in 13 patients. There was an accidental removal of the gastrostomy tube in 3 patients. In 3 cases there was an eversion of the gastric mucosa through the ostomy within the first 24-hours, and 20 days after the PEG respectively. In 2 cases there was an incarceration of the gastrostomy tube in the abdominal wall. Only two patients showed an important reflux of the gastric contents. There were no deaths as a result of PEG complications.

CONCLUSION

From our experience we can conclude the advantages of PEG as a long term nutritional support, showing a low incidence of complications, and the endoscopic technique has a zero mortality.

Hereditary ataxias and spastic paraplegias: methodological aspects of a prevalence study in Portugal

A project for studying the prevalence of hereditary ataxias (HA) and familial spastic paraplegias (FSP) in Portugal was set up in 1993. The ascertainment of patients in previous prevalence studies relied mainly on the information of hospital admissions and out-patient contacts with the neurology and other related departments at central hospitals covering the whole region surveyed. Many patients might be overlooked if large populations were studied using this method, since registers at central hospitals are very incomplete and for most part not yet computerized. On the other hand HA and FSP are rare diseases appearing in family clusters, and it would be unreasonable to undertake a sample survey based upon a suitable frame of the Portuguese population. Therefore we decided to carry out a two-phase prevalence survey at district level, involving the collaboration of all physicians working in the district health institutions and the population, in the screening of eligible subjects in phase 1. All subjects screened as positive were examined by a neurologist in phase 2. This method provided a direct estimate of false positives and false negatives were all patients also examined in phase 2, who came to our knowledge using other sources of information. The prevalence of hereditary ataxias and spastic paraplegias in the pilot district was 6.4 per 100,000 inhabitants. The sensitivity of the screening procedure was 81.2% and the predictive value of a positive screening was 25%. Considering the geographically circumscribed district nature of the populations to be studied, the comprehensive sources of case identification used and the high adherence of the health professionals involved, we believe that this method can be widely used, particularly in countries with similar health care services.