Factors associated with patent foramen ovale-related stroke: SAFAS study

BACKGROUND

Persistent foramen ovale (PFO) contributes to cryptogenic stroke and is associated with stroke recurrence, although the exact mechanism of ischemic events is not fully understood. Several biomarkers have been developed for the prediction of atrial fibrillation after stroke, but there are currently only limited data on their potential value for the diagnosis of PFO-related stroke.

METHODS

This study was a prospective single-center study that included all patients hospitalized between March 31, 2018, and January 18, 2020, in the stroke department of the Dijon University Hospital for ischemic stroke without obvious cause and without a history of atrial fibrillation. PFO was systematically screened by transthoracic echocardiography and images were reviewed by an independent cardiologist blinded from clinical data. PFO was defined according to the CLOSE trial criteria: PFO associated with interatrial septal aneurysm or significant interatrial shunt (> 30 microbubbles in the left atrium within three cardiac cycles after right atrial opacification). The potential association of PFO-related stroke with biomarkers of cardiac fibrosis and inflammation such as galectin-3, GDF-15, ST-2, osteoprotegerin and NT-proBNP was tested using multivariate backward stepwise logistic regression.

RESULTS

Of the 240 patients included in the SAFAS study, 229 had complete echocardiographic data, and 23 (10%) had PFO-related stroke. Patients with PFO-related stroke were significantly younger (58±14 vs. 69±14, P<0.001), had less frequent previous arterial hypertension (30 vs. 60%, P=0.008), and more frequent cerebellar territory involvement (26 vs. 9%, P=0.014) compared to the other patients. In addition, they had less frequently left atrial dilatation (left atrial index volume>34mL/m2 [9 vs. 35%, P=0.009]). After ROC curve analysis for definition of thresholds, PFO-related stroke patients more often had galectin-3<9.5ng/mL (59 vs. 27%, P=0.002), ST2<13380pg/ml (23 vs. 50%, P=0.007), GDF-15<1200ng/mL (59 vs. 27%, P=0.002), osteoprotegerin<1133pg/mL (82 vs. 58%, P=0.033) and NT-proBNP<300pg/mL (88 vs. 55%, P=0.009). After multivariate analysis, only galectin-3<9.5ng/mL (OR [95% CI] 3.4 [1.18; 9.8], P=0.024) and osteoprotegerin<1133pg/L (OR [95% CI] 5.0 [1.1; 22.9], P=0.038) were independently associated with PFO-related stroke.

CONCLUSION

Patients in whom cryptogenic stroke is attributed to a significant PFO have a specific clinical and biological phenotype. Low levels of galectin-3 and osteoprotegerin may help identify patients with PFO-related strokes.

The p190 RhoGAPs, ARHGAP35, and ARHGAP5 are implicated in GnRH neuronal development: Evidence from patients with idiopathic hypogonadotropic hypogonadism, zebrafish, and in vitro GAP activity assay

PURPOSE

The study aimed to identify novel genes for idiopathic hypogonadotropic hypogonadism (IHH).

METHODS

A cohort of 1387 probands with IHH underwent exome sequencing and de novo, familial, and cohort-wide investigations. Functional studies were performed on 2 p190 Rho GTPase-activating proteins (p190 RhoGAP), ARHGAP35 and ARHGAP5, which involved in vivo modeling in larval zebrafish and an in vitro p190A-GAP activity assay.

RESULTS

Rare protein-truncating variants (PTVs; n = 5) and missense variants in the RhoGAP domain (n = 7) in ARHGAP35 were identified in IHH cases (rare variant enrichment: PTV [unadjusted P = 3.1E-06] and missense [adjusted P = 4.9E-03] vs controls). Zebrafish modeling using gnrh3:egfp phenotype assessment showed that mutant larvae with deficient arhgap35a, the predominant ARHGAP35 paralog in the zebrafish brain, display decreased GnRH3-GFP+ neuronal area, a readout for IHH. In vitro GAP activity studies showed that 1 rare missense variant [ARHGAP35 p.(Arg1284Trp)] had decreased GAP activity. Rare PTVs (n = 2) also were discovered in ARHGAP5, a paralog of ARHGAP35; however, arhgap5 zebrafish mutants did not display significant GnRH3-GFP+ abnormalities.

CONCLUSION

This study identified ARHGAP35 as a new autosomal dominant genetic driver for IHH and ARHGAP5 as a candidate gene for IHH. These observations suggest a novel role for the p190 RhoGAP proteins in GnRH neuronal development and integrity.

Neuroepithelial progenitors generate and propagate non-neuronal action potentials across the spinal cord

In the developing central nervous system, electrical signaling is thought to rely exclusively on differentiating neurons as they acquire the ability to generate and propagate action potentials. Accordingly, neuroepithelial progenitors (NEPs), which give rise to all neurons and glial cells during development, have been reported to remain electrically passive. Here, we investigated the physiological properties of NEPs at the onset of spontaneous neural activity (SNA) initiating motor behavior in mouse embryonic spinal cord. Using patch-clamp recordings, we discovered that spinal NEPs exhibit spontaneous membrane depolarizations during episodes of SNA. These rhythmic depolarizations exhibited a ventral-to-dorsal gradient with the highest amplitude located in the floor plate, the ventral-most part of the neuroepithelium. Paired recordings revealed that NEPs are coupled via gap junctions and form an electrical syncytium. Although other NEPs were electrically passive, we discovered that floor-plate NEPs generated large Na⁺/Ca²⁺ action potentials. Unlike in neurons, floor-plate action potentials relied primarily on the activation of voltage-gated T-type calcium channels (TTCCs). In situ hybridization showed that all 3 known subtypes of TTCCs are predominantly expressed in the floor plate. During SNA, we found that acetylcholine released by motoneurons rhythmically triggers floor-plate action potentials by acting through nicotinic acetylcholine receptors. Finally, by expressing the genetically encoded calcium indicator GCaMP6f in the floor plate, we demonstrated that neuroepithelial action potentials are associated with calcium waves and propagate along the entire length of the spinal cord. Our work reveals a novel physiological mechanism to generate and propagate electrical signals across a neural structure independently from neurons.

[Gp IIb/IIIa receptor antagonists in acute coronary syndromes with no ST elevation]

Gp IIb/IIIa receptor antagonists have been the subject of much work in patients presenting with acute coronary syndrome with no ST elevation (ACS ST-). The initial studies (PRISM, PRISM-PLUS, PURSUIT, PARAGON, CAPTURE, GUSTO IV-ACS) were performed at the end of the 1990s and universally showed a significant reduction in an endpoint combining death and myocardial infarction, especially in patients with an elevation of troponin and treated by angioplasty. However, these studies were performed at a time when clopidogrel was not being used regularly for this indication. Four randomised studies have recently re-evaluated the significance of Gp IIb/IIIa blockers prescribed either on admission to coronary intensive care (ELISA-2, PRACTICE) or in the coronary angiography suite during angioplasty (ADVANCE, ISAR-REACT 2) in patients presenting with ACS ST- pre-treated with clopidogrel in association with aspirin and heparin. The results of these studies suggest that Gp IIb/IIIa blockers initiated at the start of angioplasty significantly reduce an endpoint combining death, myocardial infarction and the need for emergency revascularisation. On the other hand, studies in which Gp IIb/IIIa blockers are initiated in coronary intensive care have been negative, but they have only been carried out on small numbers. The results of the ACUITY study comparing bivalirudin and Gp IIb/IIIa blockers in this context have recently been published. Bivalirudin seems to compare well with Gp IIb/IIIa blockers in terms of ischemia, but it significantly reduces the occurrence of hemorrhagic events.

Magnetic resonance imaging of ruptured plaques in the rabbit with ultrasmall superparamagnetic particles of iron oxide

BACKGROUND

Magnetic resonance imaging (MRI) enhanced with ultrasmall superparamagnetic particles of iron oxide (USPIO) has previously been evaluated in hyperlipidemic rabbits. The aim of this study was therefore to compare USPIO in ruptured and non-ruptured arteries in an atherosclerotic rabbit model.

METHODS

Atherosclerotic-like lesions were induced by the combination of endothelial abrasion and high-cholesterol diet in iliac rabbit arteries (n = 16). Rupture of atherosclerotic lesions was realized by oversized balloon angioplasty in one iliac artery, whereas the contralateral artery was used as control. USPIO (ferumoxtran-10: 1 mmol Fe/kg) was administered immediately (n = 10) or 28 days (n = 6) after injury. MRI and histological analysis were performed 7 and 35 days after injury and in control arteries.

RESULTS

In vivo MRI analysis showed extended susceptibility artifact with transluminal signal loss in all ruptured arteries 7 days after injury. In contrast, hyposignal was reduced 35 days following injury (i.e. after healing), and absent in non-ruptured arteries. Similarly, histological analysis of iron uptake was significantly increased 7 days after injury compared to healed-ruptured and control arteries.

CONCLUSIONS

Accumulation ofUSPIO is significantly increased in ruptured as compared to non-ruptured arteries in the atherosclerotic rabbit model.

[Coronary angioplasty in the acute phase of a myocardial infarction on a myocardial bridge]

A myocardial bridge is usually asymptomatic but can cause myocardial ischemia, myocardial infarction or sudden death. Two occurrences of coronary angioplasty in the acute phase of an anterior myocardial infarction on a myocardial bridge are reported. The first case was first treated only with a balloon, and then with a stent 12 h later after a relapse of angina pectoris and the recurrence of a severe compression. The second case immediately benefited from a stent. A systematic control at six months has shown the absence of restenosis in the first case and an asymptomatic occlusion of the stent in the second case. Its deocclusion has revealed a myocardial bridge downstream of the stent. Myocardial stunning might have caused a decreased systolic compression by the bridge in the first case, and an underestimation of its actual length in the second case. Its regression is held responsible for these two relapses. A long active stent installed at high pressure could be used to treat myocardial bridges during myocardial infarctions.

[Anticoagulants and dental extractions]

Dental extractions in patients under platelet antiaggregant or anticoagulant therapy pose the problem of risk benefit between stopping or carrying on treatment. The difficulties of reequilibrating the INR after a heparin relay have led surgeons and cardiologists to look for alternative solutions. Different means of local haemostasis using products with haemostatic properties or not, or the use of sutures or glues, have given encouraging results but there is too much uncertainty for systematic recommendations to practicians responsible for dental extractions in these patients. The authors propose a technique which has the advantages of associating systematically different methods, making bleeding complications very unusual, without interrupting anticoagulant or antiaggregant therapy.

Usefulness and clinical impact of a fractional flow reserve and angiographic targeted strategy for coronary artery stenting: FROST III, a multicenter prospective registry

BACKGROUND

Fractional flow reserve (FFR) is correlated with angiographic and intravascular ultrasound assessments of stent placement. Post-stenting FFR has been described as a good predictor of clinical events after 6 months.

OBJECTIVE

To evaluate the feasibility and clinical impact of targeting an FFR > 0.95 via incremental in-stent inflation pressures.

METHODS

In this multicenter prospective study, 100 consecutive patients underwent FFR measurement at baseline, after balloon predilatation, and after stenting with 4-atm inflation pressure increments from 8 to 20 atmospheres. Inflations were stopped when FFR increased above 0.95 and angiographic stenosis was less than 20%.

RESULTS

FFR > 0.95 was achieved in 81% of cases; this FFR target was reached at 8 atm in 47% of patients, 12 atm in 16 %, 16 atm in 15%, and 20 atm in 3%. Fifty percent of patients with adequate angiographic result had an FFR less than 0.95 and needed further higher inflations. FFR was correlated with residual stenosis when the total procedure was evaluated, and this correlation persisted when in-stent inflations alone were considered. Final FFR was significantly correlated with anginal status after 6 months.

CONCLUSIONS

Angiography guided PCI does not allow optimization of FFR. Since optimal post stenting FFR is correlated to better anginal status at 6-months, this suggests that FFR guided PCI is required to achieve optimal functional results of PCI.

Possible involvement of gelatinase A (MMP2) and gelatinase B (MMP9) in toxic epidermal necrolysis or Stevens-Johnson syndrome

Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are considered to be drug-induced diseases, and are characterized by extensive mucocutaneous disorder and epidermal necrosis which result in the detachment of the epidermis. Inactive and active forms of metalloproteinases (MMP2 and MMP9) secreted by skin explants maintained in organ culture for 72 h and in blister fluid from two TEN and three SJS patients were investigated. Interestingly, lesional skin from both the TEN and the SJS patients cultured for 3 days in conditioned medium showed high levels of both 72 kDa progelatinase A and 66 kDa activated gelatinase A, and the 66 kDa activated form was not observed in cultures of skin from control individuals. Furthermore, indirect immunodetection showed the presence of MMP2 and MMP9 in TEN and SJS patients' skin. Increased gelatinase activity in the culture medium of TEN and SJS skin maintained in organ culture and in blister fluid indicates that these gelatinases may be responsible for the detachment of the epidermis in these drug-induced necrolyses.

In vivo induction of endothelial apoptosis leads to vessel thrombosis and endothelial denudation: a clue to the understanding of the mechanisms of thrombotic plaque erosion

BACKGROUND

The mechanisms of thrombosis on plaque erosion are poorly understood. We examined the potential role of endothelial apoptosis in endothelial erosion and vessel thrombosis.

METHODS AND RESULTS

Segments of New Zealand White rabbit femoral arteries were temporarily isolated in vivo. One artery was incubated with staurosporin for 30 minutes, whereas the contralateral artery was incubated with saline and served as control. Three days later, thrombosis was evaluated angiographically and histologically. TUNEL score in the endothelial layer was significantly increased in staurosporin-treated arteries compared with controls (2.43+/-0.30 versus 0.93+/-0.44, respectively; P=0.001). Large areas of endothelial denudation were detectable in staurosporin-treated vessels, whereas endothelium integrity was almost preserved in the saline group. Vessel thrombosis occurred in 58% of staurosporin-treated arteries (7 of 12) but in only 8% of saline-treated segments (P<0.01). Immunoreactivities for tissue factor, platelets, and fibrin were detectable within the thrombus. Addition of ZVAD-fmk (0.1 mmol/L) significantly reduced the occurrence of thrombosis (1 of 7 arteries or 14%, P=0.04). These results were confirmed in balloon-injured atheromatous arteries.

CONCLUSIONS

In vivo induction of endothelial apoptosis leads to both vessel thrombosis and endothelial denudation. Endothelial apoptosis may be a critical step in the transition from a stable endothelialized plaque to plaque erosion and thrombosis.

Drug eluting stents: are human and animal studies comparable?

Animal models of stenting probably predict human responses as the stages of healing are remarkably similar. What is characteristically different is the temporal response to healing, which is substantially prolonged in humans. The prevention of restenosis in recent clinical trials of drug eluting stents may represent a near absent or incomplete phase of intimal healing. Continued long term follow up of patients with drug eluting stents for major adverse cardiac events and angiographic restenosis is therefore imperative.

[Biochemical markers of myocardial ischemia and necrosis]

The biochemical markers of myocardial ischaemia have to be interpreted according to their kinetics; their interests depend on the clinical presentation. They are helpful to orient to a myocardial ischaemia in front of undefined chest pain, to stratify the outcome of acute coronary syndrome without ST segment elevation, to evaluate the amount of myocardial damage following infarction, to detect the failure of thrombolysis therapy and probably to stratify the post percutaneous coronary intervention outcome.

A tale of two countries: costs and financial incentives for provisional stenting during percutaneous coronary intervention in France and the United States

Provisional stenting is associated with longer physician time but the use of fewer stents. This randomized controlled trial in tertiary care in French hospitals compared strategies of systematic and provisional stenting. We estimated the costs and financial incentives associated with each strategy, based on individual data on 12-month resource use drawn from a 251-patient database. Resources were evaluated using French costs; data on costs in the United States were drawn from the literature and interviews with hospital administrators in one center. In France 1-year costs were 8,267+/-528 dollars for provisional stenting and 7,973+/-553 dollars for systematic stenting, compared to 18,715 dollars and 18,632 dollars in the United States. Given the uncertainty of longterm results, the choice between stenting strategies might be guided by financial incentives. In the United States financial incentives favor systematic stenting, while in France public hospitals and physicians are neutral.

[Beating heart in "aortic no-touch off-pump" techniques: a simple answer to complex surgical situations]

Three cases reports illustrate the concept of beating heart cardiac surgery and its advantages regarding the prevention of arterial emboli.

Doppler and angiographic endpoints: lessons from FROST and DESTINI

The strategy of provisional stenting has been guided by functional evaluation (coronary flow reserve) and anatomic evaluation (quantitative coronary angioplasty). Two trials, FROST and DESTINI, compared provisional and systematic stenting strategies. Interestingly, they showed that 43-52% of patients were not stented on the basis of angiographic and Doppler guidance. Moreover, there was no significant difference in the occurrence of restenosis (FROST) and major cardiac events (DESTINI). In conclusion, although provisional stenting appears safe and efficacious, this strategy is overshadowed by the concept of direct stenting which can shorten and simplify the procedure of angioplasty.

[Mechanical and functional predictive factors for restenosis and arterial remodeling after experimental angioplasty]

Arterial remodelling plays an important part in post-angioplasty restenosis but the physiopathology of this process is not fully understood. Abundant collagen synthesis and endothelial dysfunction have been demonstrated after angioplasty, but their role in restenosis and remodelling has not been studied. The aim of this study was therefore to assess endothelial function and collagen with respect to the severity of restenosis and the type of arterial remodelling. Atherosclerosis was induced by an association of endothelial abrasion and a high cholesterol diet in the femoral arteries of 22 white New Zealand rabbits. Four weeks later, angioplasty was performed. The acetylcholine endothelium-dependant vasomotricity (expressed as % inhibition of contraction to phenylephrine), collagen and morphology were assessed 28 days after angioplasty. The change in acetylcholine endothelium-dependant vasomotricity was greater in severe restenosis (r = 0.61, p = 0.02). Endothelium-dependant relaxation was not significantly altered when remodelling was expansive and very abnormal when it was constrictive (35.5 +/- 13.0 vs 3.7 +/- 7.9%; p = 0.04). Restenosis was associated with an increase in collagen (r = 0.69, p = 0.004). The density of collagen was significantly higher in constrictive remodelling than in expansive remodelling (34.5 +/- 4.5 vs 18.2 +/- 4.7%; p = 0.03). Endothelial dysfunction and collagen accumulation are correlated with the severity of restenosis and with constrictive remodelling after angioplasty in an experimental model.

[Use of radiotherapy in cardiovascular disease. Radiophysical basis, current results, indications and perspectives]

Restenosis is the main limitation of percutaneous angioplasty, especially in vessels of small diameters such as the coronary arteries, the femoro-popliteal and tibial-peroneal arteries and the arterio-venous dialysis grafts. The extensive use of tents has not entirely prevented its occurrence, whereas treating in-stent restenosis gives even more uncertain results. Endovascular radiotherapy has emerged over the past few years as a promising approach to both prevent and cure it. The analogy between the tumour-like cellular proliferations observed in post-angioplasty restenosis and tumour processes prompted pioneering works to study the effect of ionizing radiations in animal models of arterial restenosis. The demonstrated feasibility, tolerance and efficacy of this approach lead to test this strategy in humans. The results of 3 recently presented randomized double-blind trials in the treatment of coronary in-stent restenosis have been so promising that endovascular brachytherapy might now be considered the treatment of choice in this indication. Other randomized trials are currently carried out to test whether endovascular brachytherapy may prevent restenosis in coronary and femoro-popliteal arteries as well as in hemodialysis shunts. In the present review, we describe the basics of the biological effects of ionizing radiations, the technical modalities to deliver endovascular radiations, our current knowledge about their effects on the vascular wall and the restenosis mechanisms, and the results of the first clinical studies. Finally, we address the remaining problems in the use of endovascular curietherapy and question the promises and challenges of its clinical application.

The French Randomized Optimal Stenting Trial: a prospective evaluation of provisional stenting guided by coronary velocity reserve and quantitative coronary angiography. F.R.O.S.T. Study Group

OBJECTIVES

We sought to make a prospective comparison of systematic stenting with provisional stenting guided by Doppler measurements of coronary velocity reserve and quantitative coronary angiography.

BACKGROUND

Despite the increasing use of stents during percutaneous transluminal coronary angioplasty, it is unclear whether systematic stenting is superior to a strategy of provisional stenting in which stents are placed only in patients with unsatisfactory results or as a bail-out procedure.

METHODS

Two hundred fifty-one patients undergoing elective coronary angioplasty were randomly assigned either to provisional stenting (group 1, in which stenting was performed if postangioplasty coronary velocity reserve was <2.2 and/or residual stenosis > or =35% or as bail-out) or to systematic stenting (group 2). The primary end point was the six-month angiographic minimal lumen diameter (MLD). Major adverse cardiac events were secondary end points (death, acute myocardial infarction and target lesion revascularization).

RESULTS

Stenting was performed in 48.4% of patients in group 1 and 100% of patients in group 2 (p<0.01). Six months after angioplasty, the MLD did not differ between groups (1.90+/-0.79 mm vs. 1.99+/-0.70 mm, p = 0.39), as was the rate of binary restenosis (27.1% vs. 21.4%, p = 0.37). Among patients with restenosis, 13/32 (40.6%) in group 1 but 100% (25/25) in group 2 had in-stent restenosis (p<0.01). Target lesion revascularization (15.1% vs. 14.4% in groups 1 and 2 respectively, p = 0.89) and major adverse cardiac events (15.1% vs. 16.0%, p = 0.85) were not significantly different.

CONCLUSIONS

Systematic stenting does not provide superior angiographic results at six months as compared with provisional stenting.

A comparison of systematic stenting and conventional balloon angioplasty during primary percutaneous transluminal coronary angioplasty for acute myocardial infarction. STENTIM-2 Investigators

OBJECTIVES

In a multicenter, randomized trial, systematic stenting using the Wiktor stent was compared to conventional balloon angioplasty with provisional stenting for the treatment of acute myocardial infarction (AMI).

BACKGROUND

Primary angioplasty in AMI is limited by in-hospital recurrent ischemia and a high restenosis rate.

METHODS

A total of 211 patients with AMI <12 h from symptom onset, with an occluded native coronary artery, were randomly assigned to systematic stenting (n = 101) or balloon angioplasty (n = 110). The primary end point was the binary six-month restenosis rate determined by core laboratory quantitative angiographic analysis.

RESULTS

Angiographic success (Thrombolysis in Myocardial Infarction [TIMI] flow grade 3 and residual diameter stenosis <50%) was achieved in 86% of the patients in the stent group and in 82.7% of those in the balloon angioplasty group (p = 0.5). Compared with the 3% cross-over in the stent group, cross-over to stenting was required in 36.4% of patients in the balloon angioplasty group (p = 0.0001). Six-month binary restenosis (> or = 50% residual stenosis) rates were 25.3% in the stent group and 39.6% in the balloon angioplasty group (p = 0.04). At six months, the event-free survival rates were 81.2% in the stent group and 72.7% in the balloon angioplasty group (p = 0.14), and the repeat revascularization rates were 16.8% and 26.4%, respectively (p = 0.1). At one year, the event-free survival rates were 80.2% in the stent group and 71.8% in the balloon angioplasty group (p = 0.16), and the repeat revascularization rates were 17.8% and 28.2%, respectively (p = 0.1).

CONCLUSIONS

In the setting of primary angioplasty for AMI, as compared with a strategy of conventional balloon angioplasty, systematic stenting using the Wiktor stent results in lower rates of angiographic restenosis.

[Local treatment during angioplasty]

Intracoronary thrombosis and post-angioplasty complications (acute occlusion) are now controlled. Restenosis is the principal obstacle to transluminal coronary revascularisation. The conviction of the multifactorial and focal nature of the process leading to this excessive scarring is acquired. Constrictive remodelling is now established as the main mechanism of restenosis. Failure to prevent restenosis by systemic therapy has led several groups to experiment local treatment for this problem. The object of this article is to review the different systems of local treatment at the site of angioplasty. Even if some results are encouraging, there is no solution as yet to the problem of restenosis. Although local therapy is possible, the agent(s) of choice remain(s) to be defined.

Endothelial dysfunction and collagen accumulation: two independent factors for restenosis and constrictive remodeling after experimental angioplasty

BACKGROUND

Constrictive remodeling plays a prominent role in restenosis after balloon angioplasty, but its regulation remains unclear. Because endothelial dysfunction and changes in extracellular matrix have been reported after angioplasty, this study was designed to simultaneously evaluate endothelial function and collagen and elastin changes after restenosis and arterial remodeling.

METHODS AND RESULTS

Atherosclerosis was induced in femoral arteries of 22 New Zealand White rabbits by air-desiccation and a high-cholesterol diet. One month later, angioplasty was performed. Histomorphometry and in vitro assessment of endothelial function were performed 4 weeks after angioplasty. Restenosis correlated with constrictive remodeling (r=0.60, P=0.01) but not with neointimal growth (r=-0.06, P=0.79). Restenosis correlated with an impaired relaxation to acetylcholine (ACh; r=0.61, P=0.02) but not with the response to the endothelium-independent vasodilator sodium nitroprusside (r=-0.25, P=0.40). Restenosis correlated positively with collagen accumulation (r=0.69, P=0.004) and inversely with elastin density (r=-0.48, P=0.05). Relaxations to ACh were significantly more decreased in arteries with constrictive remodeling than in those with enlargement remodeling (3.7+/-7.9% versus 35.5+/-15.0%, P=0.04). Neointimal collagen density was significantly higher in arteries with constrictive remodeling than in those with enlargement remodeling (34.5+/-4.5% versus 18.2+/-4.7%, P=0.03). Endothelial function and collagen and elastin density were independent predictors of restenosis in the study.

CONCLUSIONS

These results demonstrate that the severity of restenosis after angioplasty correlated with both defective endothelium-dependent relaxation and increased collagen density.

Thrombus generation after adenovirus-mediated gene transfer into atherosclerotic arteries

Thrombosis represents a major issue during arterial local delivery. We evaluated the occurrence of thrombosis after adenovirus (Ad)-mediated gene transfer into normal and atherosclerotic arteries. A replication-deficient Ad vector expressing the beta-galactosidase reporter gene (Ad.RSV betagal; 4 x 10(9) PFU) was injected into normal and atherosclerotic arteries (n = 11 in both groups). The contralateral artery received either an Ad vector carrying no transgene (Ad.MLPnull) (n = 7 in both groups, 4 x 10(9) PFU) or vehicle buffer (n = 4 in normal group, n = 8 in atherosclerotic group). Animals were sacrificed 3 days following gene transfer for thrombus detection and assessment of beta-galactosidase activity. Thrombus was absent in normal arteries and in atherosclerotic arteries injected with vehicle buffer only. In contrast, nonocclusive thrombus was present in atherosclerotic arteries injected with either Ad.RSV betagal (5 of 11) or Ad.MLPnull (3 of 7). Beta-galactosidase activity was predominantly found in the endothelial layer of the transfected arteries. Gene transfer and expression occurred despite the presence of the thrombus (4 of 5), and its efficiency did not significantly differ regardless of the thrombus. We conclude that thrombus frequently occurred in atherosclerotic arteries after Ad-mediated gene transfer. Further studies are warranted to identify the mechanisms of thrombus generation after Ad-mediated gene transfer into atherosclerotic arteries.

Epidemiology of peptic ulcer disease in cirrhotic patients: role of Helicobacter pylori infection

OBJECTIVE

The aim of this study was to investigate the clinical and epidemiological factors associated with the appearance of peptic ulcer in patients with cirrhosis and, in particular, the role of Helicobacter pylori infection.

METHODS

A total of 201 of 220 consecutive patients included in a prospective study that aimed to evaluate the effect of dietary intervention on cirrhotic complications and survival underwent upper gastrointestinal endoscopy. At entry, an epidemiological and clinical questionnaire was completed and the presence of peptic ulcer disease or esophageal varices at endoscopy was prospectively collected. Sera were obtained and stored at -70 degrees C until analyzed, being tested afterward for Helicobacter pylori antibodies using a commercial ELISA kit.

RESULTS

Eleven of 201 patients had borderline anti-Helicobacter pylori IgG titers and were excluded from further analysis. In the remaining 190 patients, point prevalence of peptic ulcer was 10.5% and lifetime prevalence 24.7%. Multivariate analysis selected male sex (OR 2.3; 95%CI 1.09-4.89) and Helicobacter pylori seropositivity (OR: 1.7, 95%CI 1.02-2.81) as the variables independently related to peptic ulcer disease.

CONCLUSIONS

Male sex and seropositivity for Helicobacter pylori are the major risk factors for peptic ulcer in cirrhosis.

The smooth muscle cell: sinner or saint in restenosis and the acute coronary syndromes?

Proliferation of arterial smooth muscle cells has held center stage as the culprit in restenosis for almost two decades. Many strategies for combating restenosis target smooth muscle replication. However, none have proven beneficial in clinical trials. Indeed, inhibition of smooth muscle proliferation in human patients might produce the undesired effect of destabilizing vulnerable atherosclerotic plaques because these cells furnish the collagen responsible for the biomechanical strength of the plaque. Actually, in some cases the benefit of angioplasty may depend on stimulating smooth muscle replication and collagen elaboration, converting an "unstable" to a more stable plaque. Moreover, recent clinical and experimental evidence suggests that restenosis depends less on neointimal hyperplasia than on constrictive remodeling (i.e., advential scarring, producing a smaller lumen), a process independent of smooth muscle replication. The recognition that plaques vulnerable to disruption often do not produce flow-limiting stenoses highlights a need for reassessment of the strategies to treat or prevent the acute coronary syndromes. We should strive to treat aggressively risk factors such as hyperlipidemia whose control appears to stabilize plaques. Trials are even underway comparing such risk factor management with coronary artery intervention. If we could identify potentially unstable atheroma before they are evident, clinically, we might even contemplate angioplasty of nonsignificant stenoses to induce smooth muscle cell proliferation and reinforce the plaque's fibrous cap. This proposal may seem preposterous, yet we perform "primary" angioplasty every day in patients with an acute myocardial infarction whose "culprit" lesions underlying the thrombus are often not critical. Our knowledge of the biology of restenosis has lagged behind our practice of coronary intervention. Advances in understanding the biology of the complications of interventional therapy, hand in hand with technical advances, should help us to devise more rational and enduring approaches to benefiting our patients.

[Mechanisms and prevention of restenosis after coronary angioplasty]

The success of PTCA is limited by late restenosis, which occurs in 30-50% of all cases, chiefly within the first six months after the intervention. Restenosis is due to the proliferation of smooth muscle cells and especially to overproduction of extracellular matrix in the arterial wall. The coronary intervention is followed by a not fully defined constrictive process of wound healing, so-called remodeling. Various alternative intervention techniques were investigated but did not show any clear advantage concerning restenosis compared to PTCA. Although the rate of restenosis is reduced by stent implantation, which hinders remodeling, the remaining intimal hyperplasia often leads to restenosis. In spite of promising results in animal models, to date no effective human pharmacological therapy has been found to prevent restenosis. To determine whether antioxidants, endovascular radiation or gene therapy show any benefit will require further, larger trials.

Remodelling: therapeutic opportunities

Restenosis after angioplasty has been recently attributed to a lack of compensatory enlargement and/or chronic constrictive remodelling, rather than neointimal growth. Also, restenosis occurring after stent has been clearly related to neointimal growth. This clarification has dramatically helped in designing strategies targeted against the appropriate mechanisms. The mechanism of stent-related restenosis has been the most studied and several antiproliferative agents including gene therapy and radioactive stents have been successfully tested. Constrictive remodelling has been identified more recently and its pathophysiological mechanism remains poorly understood. Control of extracellular matrix metabolism might be an important pathway. Moreover, detection of the arteries that will 'enlarge' should avoid any preventive strategy including systematic stenting.

Vasomotor dysfunction early after exposure of normal rabbit arteries to an adenoviral vector

We aimed to investigate whether infection of normal rabbit arteries with a recombinant adenovirus vector would result per se in alterations in contractile and endothelial functions. In one group of rabbits, right or left femoral and ear artery segments were injected in vivo with a replication-deficient adenoviral vector expressing a beta-galactosidase (beta-Gal) reporter gene (4 x 10(10) pfu/ml) to demonstrate efficient gene transfer. Contralateral arteries were injected with the same concentration of a recombinant adenoviral vector carrying no transgene (Ad.MLPnull). In another group of animals, Ad.MLPnull was injected into the lumen of femoral and ear artery segments. The contralateral arteries were used as controls with the injection of vehicle alone. Histochemical assessment of gene transfer using beta-Gal activity (group 1) or in vitro contractility and endothelial function (group 2) was performed 3 days after adenoviral infection. Gene transfer was efficient and reproducible in the endothelium and was associated with the presence of inflammatory cells in the media. In Ad.MLPnull-injected arteries, in vitro contractile response of femoral artery rings to either KCl 60 mM or phenylephrine (10 microM) was reduced to 10.5 +/- 2.3% (n = 14; p < 0.001) and 8.8 +/- 2.0% (n = 7; p < 0.001) of the control values, respectively. Furthermore, in arteries injected with Ad.MLPnull, the endothelium-dependent relaxation produced by acetylcholine (10 microM) was virtually abolished. Similarly, the relaxant effects of the alpha 2-adrenoreceptor agonist UK14304 (1 microM) or the Ca2+ ionophore A23187 (1 microM) were also abolished. By contrast, sodium nitroprusside (10 microM) was still able to relax adenovirus-infected arteries. We conclude that infection with a recombinant adenoviral vector can induce early severe vasomotor alterations in both contractile function and endothelium-mediated relaxation of normal rabbit arteries.

[Compensatory enlargement versus chronic constriction. The two features of vascular remodelling after experimental angioplasty]

Considerable efforts have been made to prevent post-angioplasty restenosis targeted mainly against a pathogenesis suggesting a dominant role of hyperplasia. We and others have already shown that constrictive remodelling plays a major role in restenosis. This article evaluates not only the constrictive remodeling theory but also compensatory enlargement associated with prevention of restenosis. The present study on 33 rabbits used the following protocol. Four weeks after inducing an atherosclerotic lesion by air-dessication of a femoral artery segment and a high cholesterol diet, angioplasty was performed. The angiographic minimal luminal diameter significantly increased after angioplasty. Three to four weeks later, initial gain was significantly lost. Restenosis was quantified histologically as well as a remodelling index and a hyperplasia index. No correlations were observed between degree of stenosis and hyperplasia present at the same degree in animals with and without restenosis. On the other hand, there was a strong correlation between restenosis and constrictive remodelling, and with absence of restenosis and compensatory enlargement. Moreover, there was significant a correlation between the degree of hyperplasia and the compensatory remodelling. These data point to the double nature of remodelling: compensatory enlargement observed in animals without restenosis, and constrictive remodelling, the principal mechanism observed in animals with restenosis.

Seroprevalence and epidemiology of Helicobacter pylori infection in patients with cirrhosis

BACKGROUND

Helicobacter pylori infection is the major pathogenic factor for peptic ulcer disease. Its epidemiology is not fully known; few data are available in patients with chronic liver disease.

AIMS

To investigate the seroprevalence and factors associated with Helicobacter pylori infection in a series of liver cirrhosis patients.

METHODS

Two hundred and twenty consecutive patients were prospectively included in a study aimed to evaluate the effect of dietary intervention on cirrhosis complications and survival. At inclusion, an epidemiological and clinical questionnaire was completed. Sera were obtained and stored at -70 degrees C until analyzed. They were tested for Helicobacter pylori antibodies using a commercial ELISA kit.

RESULTS

Eleven out of 220 patients had borderline anti-Helicobacter pylori IgG titers. Of the remaining 209 patients, 105 (50.2%) showed positive titers of Helicobacter pylori IgG. Univariate analysis showed that Helicobacter pylori infection was more frequent in older patients, those born outside Catalonia, and in patients with a low educational level. Past ethanol consumption and current smoking correlated negatively with Helicobacter pylori infection. Multivariate analysis selected age (OR 3.1. 95% CI 1.46-6.45), educational level (OR 2.2. 95% CI 1.18-4.2) and alcohol consumption (OR 0.7. 95% CI 0.45-0.99) as the variables independently related to Helicobacter pylori infection.

CONCLUSIONS

Helicobacter pylori infection in cirrhosis has the same epidemiological pattern as in the general population. Suggestions that the etiology or the severity of the liver disease could be related to Helicobacter pylori infection were not confirmed by our study.

[Should a main coronary artery be dilated when the controlateral vessel is occluded?]

Angioplasty of the dominant left anterior descending or right coronary arteries when the controlateral artery is occluded may lead to major left ventricular dysfunction or cardiogenic shock. The authors assessed the results of angioplasty of a right coronary (n = 52) or left anterior descending (n = 141) artery stenosis when the controlateral artery was occluded and the left circumflex had no significant stenosis in 193 patients. The immediate and late (33 +/- 18 months) results were compared in 3 groups: the study group, a reference surgical group in which patients with comparable coronary lesions underwent double coronary artery bypass and a reference angioplasty group (n = 194) in which patients were treated by angioplasty of the right coronary and left anterior descending arteries. The left ventricular function of the study group was normal or midly abnormal in 72% of cases and moderately to severely abnormal in 28% of cases. During the hospital period, for the study group, there were 5.7% emergency coronary bypass procedures and 2.6% non-emergency bypass procedures, 1.6% of myocardial infarction and 0.5% deaths. After hospital discharge, the study group had 13.1% of coronary bypass procedures, 3.7% of myocardial infarcts and 4.7% deaths. The death and infarction rates were comparable in the 3 groups. The study group had a higher incidence of coronary bypass surgery in and after the hospital period than the control surgical group (p = 0.0.002). The authors conclude that dilatation of a main coronary artery when the controlateral artery is occluded is as safe as double coronary artery bypass surgery and angioplasty of the two vessels. Incomplete revascularisation in the study group did not affect survival rate without myocardial infarction compared with the angioplasty and surgical reference groups.

Decreased free radical scavengers with reperfusion after coronary angioplasty in patients with acute myocardial infarction

Early reperfusion after myocardial infarction improves survival rate and is thought to preserve myocardial function, but the reperfusion of ischemic tissue may release oxygen free radicals, which could adversely affect left ventricular function and diminish the beneficial effects of reperfusion. Measurements related to free radical scavenging (plasma and erythrocyte enzyme systems, which are involved in free radical control, alpha-tocopherol, selenium, and manganese superoxide dismutase) may be indirect markers of free radical production. We evaluated 10 patients undergoing coronary angioplasty within 4 hours of myocardial infarction to measure the impact of abrupt reperfusion on free radical scavenger-related indexes. Pulmonary artery samples were taken before, immediately after, and 3 hours after angioplasty. During reperfusion, significant reductions occurred in alpha-tocopherol (1.1 +/- 0.3 mg/dl before, 0.9 +/- 0.2 mg/dl immediately after [p = 0.03], and 0.8 +/- 0.2 mg/dl 3 hours after percutaneous transluminal coronary angioplasty [p = 0.02]), and selenium levels (13.7 +/- 2.4 micrograms/dl before, 12.9 +/- 2.4 micrograms/dl immediately after, and 10.2 +/- 3.0 micrograms/dl 3 hours after angioplasty [p = 0.0006]). Erythrocyte markers (glutathione peroxidase and superoxide dismutase) were not altered by reperfusion, possibly reflecting the relatively long half-life of the erythrocyte. The erythrocyte glutathione peroxidase value before reperfusion in patients (30.8 +/- 5.1 IU/gm of hemoglobin) was lower than in a control group (36.1 +/- 6.5 IU/gm of hemoglobin; p = 0.01). Thus the decrease in plasma alpha-tocopherol and selenium after reperfusion in this group of patients may reflect a general alteration in plasma free radical scavenger levels, suggesting consumption of plasma free radical scavengers with reperfusion after acute myocardial infarction.

[Granulomatous mastitis]

Six cases of granulomatous mastitis are reported. Based on a review of the relevant literature, the clinical features, etiology, and management of this pathologic entity are discussed. The definition of granulomatous mastitis is given and the characteristics that distinguish this condition from other inflammatory breast diseases are pointed out.

[Restenosis: physiopathology, treatments and prevention]

Despite fifteen years of extensive research, we still do not know how to predict or prevent restenosis. Angioplasty induces lesions in the intima, media and sometimes adventitia, resulting in a cicatricial process comprising proliferation and migration of smooth muscle cells towards the intima and secretion of extracellular matrix, leading to the formation of a neointima. Since angioplasty is associated with the simultaneous development of neointimal hyperplasia and restenosis, a cause and a effect relationship has therefore been proposed between neointimal hyperplasia and restenosis. All the restenosis prevention strategies based on inhibition of smooth muscle cell proliferation, which successfully limited restenosis in animal models have failed in man, due to the hazardous extrapolations from experimental models which are very different from the atheromatous lesions observed in man, rather than to the use of animal models in general. It is reasonable to wonder whether we have not selected the wrong target: is smooth muscle cell proliferation really responsible for restenosis? Experimental results supported by histological and ultrasonographic data in man, show that the cicatricial process which induces restenosis consists of constrictive remodelling, which decreases the perimeter of the external elastic lamina and the lumen. The use of stents appears to be the primary strategy designed to limit restenosis and prevent constrictive remodelling in man, even if it stimulates neointimal hyperplasia. Progress in the understanding of the mechanisms of postangioplasty remodelling open new perspectives in the prevention of restenosis.

Restenosis after experimental angioplasty. Intimal, medial, and adventitial changes associated with constrictive remodeling

Predicting and preventing arterial restenosis after angioplasty has failed despite considerable research into mechanisms and techniques. We examined the roles of chronic constriction, neointimal-medial growth, and adventitial changes in restenosis in atherosclerotic rabbits. Angioplasty was performed on femoral artery lesions 4 weeks after lesion induction by air drying and cholesterol-supplemented diet. Angiographic and histological evaluation was conducted 3 to 4 weeks after angioplasty. The angiographic minimum luminal diameter (MLD) increased from 1.31 +/- 0.21 to 1.73 +/- 0.41 mm after angioplasty. Loss in MLD by 3 to 4 weeks was 0.95 +/- 0.64 mm. Initial gain and late loss correlated (P = .008). Late residual stenosis, defined histologically as the difference between the luminal areas of a proximal reference site and lesion site normalized by the luminal area of the reference site, was 52 +/- 32%. Histological indices of chronic constriction, neointimal-medial growth, and adventitial growth were defined on the basis of the areas of these arterial wall layers at the lesion site relative to the reference site. Another parameter defined as the ratio of adventitial area to the area of intima+media at the lesion site allowed evaluation of the relative importance of these layers. Surprisingly, late residual stenosis correlated with chronic constriction (P = .0003) but not with neointimal-medial growth or adventitial growth. The ratio of adventitial area to the area of intima+media at the lesion site also correlated with chronic constriction (P = .01). These findings suggest that factors related to arterial remodeling rather than neointimal-medial growth may dominate the response to angioplasty.

Candida albicans spondylodiscitis and vertebral osteomyelitis in patients with intravenous heroin drug addiction. Report of 3 new cases

We describe 3 patients with a history of intravenous (iv) heroin addiction presenting with indolent, persisting lumbar pain. Clinical findings and initial investigations were unremarkable. Gallium scintigraphy revealed septic spondylodiscitis, and cultures of material obtained by biopsy were positive for Candida albicans in all 3 cases. Two patients were treated with iv amphotericin B and the other with fluconazole with excellent results. Surgical treatment was needed only in one patient because of neurological involvement.

Percutaneous transluminal coronary angioplasty of one major coronary artery when the contralateral vessel is occluded

OBJECTIVES

In 193 patients we evaluated the safety and efficacy of angioplasty of a critical stenosis of the right coronary artery (52 patients) or the left anterior descending coronary artery (141 patients), with the contralateral coronary artery occluded and the circumflex artery being without significant stenosis.

BACKGROUND

Attempted angioplasty of either the left anterior descending or the dominant right coronary artery when the contralateral vessel is occluded may trigger overwhelming left ventricular dysfunction or hemodynamic collapse, or both.

METHODS

Immediate and late outcome (33 +/- 18 months) in the study group were compared with outcome in 214 patients who had angioplasty in both the left anterior descending and right coronary arteries and in 194 patients who had coronary artery surgery and were matched for number and location of significant lesions, ejection fraction, age, gender and study period.

RESULTS

Left ventricular function was normal (38%) or mildly (34%), moderately (22%) or severely (6%) compromised. There were 11 (5.7%) emergency and 5 (2.6%) elective coronary artery operations, 3 (1.6%) myocardial infarctions and 1 in-hospital death in the study group. After discharge there were 25 (13.1%) elective coronary operations, 7 (3.7%) myocardial infarctions and 9 (4.7%) deaths in the study group. The incidence of death and myocardial infarction was similar in all groups, with 80% power to detect a 7% difference in adverse events. The study group had more elective surgery before and after discharge than did the surgical control group (p = 0.02).

CONCLUSIONS

Dilating one major vessel when the contralateral vessel is occluded appears to be as safe as coronary surgery or two-vessel angioplasty. Incomplete revascularization in study group patients did not impair survival or increase myocardial infarction compared with the angioplasty and surgical control groups.

Protection against ischemia during prolonged balloon inflation by distal coronary perfusion with use of an autoperfusion catheter or Fluosol

OBJECTIVES

The purpose of this report was to study the protective effects of passive and active distal coronary perfusion during prolonged balloon inflation.

BACKGROUND

Prolonged balloon inflation has been proposed to improve immediate and long-term results of percutaneous transluminal coronary angioplasty, but it requires protection against myocardial ischemia.

METHODS

A 30-min balloon occlusion of the left anterior descending artery was performed in three groups of closed chest anesthetized dogs: 1) control (no distal coronary perfusion, n = 13), 2) passive distal coronary perfusion (autoperfusion catheter, n = 10), and 3) active distal coronary perfusion (infusion of the perfluorochemical Fluosol at 30 ml/min, n = 11).

RESULTS

At 10 min of balloon inflation, echocardiographic wall motion indexes (scored from 1 [normal] to 5 [dyskinesia]) in the autoperfusion catheter and Fluosol groups (2.4 +/- 1.2 and 2.0 +/- 0.9, respectively) were significantly better than in the control group (3.6 +/- 0.4, p = 0.001), but at 25 min this improvement in wall motion had attenuated and became statistically insignificant when compared with values in the control group. Left ventricular end-diastolic pressure at peak inflation in the Fluosol group (19.5 +/- 5.5 mm Hg) was higher than in the control (7.6 +/- 3.6) and autoperfusion catheter (5.3 +/- 1.4, p < or = 0.01) groups. Pathologic evidence of infarction by tetrazolium staining was seen in three control dogs and in none of the other groups (p = 0.07). Ventricular tachycardia and fibrillation were less frequent in the autoperfusion catheter group (p = 0.02). Three deaths were observed in the control dogs, two in the Fluosol group and none in the dogs with an autoperfusion catheter (p = NS).

CONCLUSIONS

Passive (the autoperfusion balloon catheter) and active (Fluosol) distal coronary perfusion methods are comparable and better than no perfusion in protecting the myocardium against ischemia produced by prolonged coronary balloon inflation in an experimental canine model. This protection is transient, attenuating after 10 to 25 min, and partial because there was no significant difference in the incidence of myocardial infarction and death among groups, although the latter observations may be related to small sample size.

Identification of recurrent ischemia after coronary artery bypass surgery: a comparison of positron emission tomography and single photon emission computed tomography

Current techniques for the detection of recurrent coronary stenoses following bypass grafting have shown disappointing diagnostic accuracy. This study used the same dipyridamole-handgrip stress to compare the accuracy of rubidium-82 positron emission tomography and thallium-201 single photon emission computed tomography, in 50 consecutive post-bypass patients undergoing coronary arteriography at a mean interval of 6.5 years after surgery. Significant stenoses in native coronary vessels (greater than 50% diameter) or grafts (greater than 70% diameter) were defined by quantitative angiography. Forty-six patients had recurrent or residual stenoses, 43 (93%) had a perfusion defect identified by positron emission tomography, and 35 (76%) were identified by single photon emission computed tomography (P = 0.04). Fourteen of the 17 patients (82%) without previous Q-wave myocardial infarction were identified by positron emission tomography; 10 of the 17 (59%) were detected by single photon emission computed tomography (P = NS). Stress-induced perfusion defects were demonstrated by positron emission tomography in 19 patients; of this group, thallium imaging identified reversible defects in 11, showed no perfusion defect in 1, and portrayed a persistent defect in 7 patients. Significant graft disease was present in 33 patients; perfusion defects were identified by positron emission tomography in 30 (91%), and by single photon emission computed tomography in 24 (73%, P = NS). Four patients were fully revascularized, without significant recurrent coronary disease; normal perfusion was present in 3 (75%) by positron emission tomography, and 4 (100%) by single photon emission computed tomography.(ABSTRACT TRUNCATED AT 250 WORDS)