Blockade of GABA(B) receptors completely reverses age-related learning impairment

Impaired cognitive functions are well-described in the aging process. GABA(B) antagonists can facilitate learning and memory in young subjects, but these agents have not been well-characterized in aging. Here we show a complete reversal of olfactory discrimination learning deficits in cognitively-impaired aged Fischer 344 rats using the GABA(B) antagonist CGP55845, such that drug treatment restored performance to that on par with young and cognitively-unimpaired aged subjects. There was no evidence that this improved learning was due to enhanced olfactory detection abilities produced by the drug. These results highlight the potential of targeting GABA(B) receptors to ameliorate age-related cognitive deficits and demonstrate the utility of olfactory discrimination learning as a preclinical model for testing novel therapies to improve cognitive functions in aging.

Feasibility of intravascular ultrasound studies: predictors of imaging success before coronary interventions

BACKGROUND

Intravascular ultrasound (IVUS) is currently used to study lesions during transcatheter coronary therapy. However, before dilation some lesions cannot be reached or crossed with the imaging catheter.

HYPOTHESIS

This study seeks to elucidate which factors determine the feasibility of IVUS examination before coronary interventions.

METHODS

Accordingly, 100 consecutive patients undergoing IVUS examination before coronary angioplasty were prospectively studied. The clinical and angiographic characteristics of 77 patients with a successful IVUS study (Group A) were compared with those of 23 patients in whom IVUS was attempted but the target lesion could not be interrogated (Group B). The echogenic characteristics of the target lesion [before (n = 77) or after intervention (in 18 patients in Group B)] were also studied.

RESULTS

Patients in Group B were significantly older (62 +/- 7 vs. 57 +/- 10 years, p < 0.05) and more frequently had stable angina [8 (35%) vs. 9 (11%), p < 0.05]. The distribution of lesions within the coronary tree and angiographic lesion characteristics including length, eccentricity, calcification, bend location, and the American College of Cardiology/American Heart Association classification were similar in both groups. However, proximal tortuosities (> 45 degrees at end diastole) were more frequently found in Group B [20 (87%) vs. 47 (61%), p < 0.05]. In addition, by quantitative angiography, patients in Group B had smaller arteries (reference diameter 2.8 +/- 0.4 vs. 3.1 +/- 0.4 mm, p < 0.05) and more severe lesions (minimal lumen diameter 0.46 +/- 0.24 vs. 0.65 +/- 0.34 mm, p < 0.05). On IVUS, calcified lesions were more frequently visualized in Group B (61 vs. 38%, p < 0.05). On multivariate analysis, catheter size, baseline minimal lumen diameter, angiographic proximal tortuosities, and lesion calcification on imaging were independent predictors of the feasibility of IVUS studies.

CONCLUSIONS

Unsuccessful IVUS studies before intervention occur more frequently (1) in vessels with proximal tortuosities or severe lumen narrowing, (2) in lesions that are calcified on IVUS, and (3) when large imaging catheters are used.

[Clinical management of terrorist bomb explosions]

At 07:39 on 11 March 2004 terrorist bomb explosions ocurred in 4 trains in Madrid killing 177 people instantly and 14 more later in the hospital. This report describes the organization, clinical management and patterns of injuries in casualties who were taken to our chil-patients were taken to the Gregorio Marañon hospital and 12 to the children's one. The mean age was 16 years (14-21), Two of them were critically ill and needed intensive care (ITP 5). Tympanic perforations occurred in 81% victims with moderate to severe trauma, shrapnel wounds in 36% and eye lesions in 27%. Among critically ill patients blast lung injury, cranial and abdominal trauma were the most important lesions. Training in AITP courses and hospital logistics were essential in clinical management of these casualties.

Functional characterization of EhADH112: an Entamoeba histolytica Bro1 domain-containing protein

EhADH112 is part of the EhCPADH complex, a protein involved in key events of the Entamoeba histolytica host invasion. EhADH112 participates in trophozoite adherence to target cells and in phagocytosis. We report here the finding of two EhADH112 homologues in the E. histolytica genome (EhADH112-like proteins). EhADH112 and its relatives have a Bro1 domain at their amino-terminus and a consensus context for phosphorylation by Src-tyrosine kinases, both involved in signal transduction processes in other organisms. Our findings associate EhADH112 to supplementary functions related to those reported for the Alix/AIP1 family. To elucidate the precise function of EhADH112, we studied the phenotypes displayed by trophozoites transfected with the Ehadh112 full gene. Transfected trophozoites overexpressed a 78 kDa protein, which was mainly targeted to the EhCPADH complex. Moreover, these trophozoites exhibited enhanced phagocytic rates, providing further evidence of EhADH112 contribution to adhesion and phagocytosis activities.

Findings of intravascular ultrasound during acute stent thrombosis

OBJECTIVE

To evaluate the potential role of intravascular ultrasound (IVUS) in evaluating patients experiencing an episode of acute stent thrombosis.

DESIGN AND SETTING

Prospective observational study in a cardiac catheterisation laboratory in a university teaching hospital.

PATIENTS AND INTERVENTIONS

IVUS was used to examine 12 patients undergoing coronary interventions for stent thrombosis to gain further mechanistic insights and to guide treatment. IVUS studies were obtained before and after intervention with a motorised pullback device.

MAIN OUTCOME MEASURES

Qualitative and volumetric IVUS analyses.

RESULTS

Angiographically, 10 patients had occluded vessels and two patients had intraluminal filling defects within the stent. IVUS showed an occlusive thrombus in all patients. Thrombus volume was 90 (77) mm3, which was 51 (21)% of total stent volume. There was evidence of severe stent underexpansion in most patients and no patient fulfilled standard criteria for optimal stent implantation. Stent malapposition was detected in four patients, edge dissections were seen in two patients, and significant inflow-outflow disease was present in 11 patients. During interventions IVUS findings led to the use of higher pressures or larger balloons than those used during initial stenting in 10 patients. In addition, four patients required additional stenting, whereas a thrombectomy device alone was selected for one patient. After the procedure final minimum stent area (7.1 (2.1) v 5.3 (2) mm2, p < 0.005) and stent expansion (83.2 (17) v 62.1 (15)%, p < 0.005) improved compared with pre-interventional values. However, residual lining thrombus was still visualised in eight patients (25 (19) mm3, accounting for a 17% of final stent volume).

CONCLUSIONS

IVUS provides an attractive technique to characterise fully the pattern of stent thrombosis, to identify readily the underlying mechanical predisposing factors, and to guide repeated coronary interventions.

Multidrug resistance in the protozoan parasite Entamoeba histolytica

In this review we discuss the mechanisms and molecules involved in the multidrug resistance (MDR) of the protozoan parasite Entamoeba histolytica. Drug resistant mutants exhibited the main characteristics presented by the MDR mammalian cells. They showed cross-resistance to several unrelated drugs that is reverted by calcium channel blockers. MDR phenotype in E. histolytica is regulated at a transcriptional level by the EhPgp1 gene, which is constitutively expressed and by the EhPgp5 gene, whose expression is induced in the presence of the drug. Transcription factors participate in the expression regulation of these genes. After over transcription, the EhPgp genes are amplified, cooperating to produce the MDR phenotype. Post-transcriptional mechanisms such as mRNA stability seem to be involved in this phenomenon. As for other mdr gene products, the EhPGP5 protein functions as a chloride current inductor or as a regulator of cellular regulatory volume decrease.

Endogenous anti-inflammatory response after coronary injury in a porcine model

BACKGROUND

Corticotropin-releasing hormone (CRH)/adrenocorticotropic hormone (ACTH)/cortisol is the major anti-inflammatory system. After percutaneous translumenal angioplasty, an inflammatory process is triggered. We investigate whether CRH/ACTH/cortisol axis is activated after deep vessel wall injury (DVWI).

MATERIALS AND METHODS

Plasma and leukocyte CRH and ACTH, serum cortisol and IL-1beta, and leukocyte cAMP were measured (ELISA) in 16 pigs after anaesthesia (baseline), 60 min into anaesthesia without causing vascular injury and 90 min after DVWI of the left anterior descending (LAD) coronary artery induced by percutaneous directional atherectomy (Atherocath GTO 7F; DVI, Inc., Temecula, USA). Biochemical variables were also measured at baseline, 60 and 180 min into anaesthesia in six additional pigs without coronary intervention.

RESULTS

MANOVA showed that CRH/ACTH/Cortisol, cAMP and IL-1beta production was not modified during anaesthesia. Post-DVWI plasma CRH (0.077 +/- 0.046 ng mL-1), and cellular cAMP (0.14 +/- 0.067 pmol 10(-6) cells) increased significantly (P = 0.001) with respect to their baseline values (CRH = 0.036 +/- 0.013 ng mL-1; cAMP = 0.081 +/- 0.034 pmol 10-6). There was also a statistically significant increase (P = 0.02) in post-DVWI IL-1beta (from 46.6 +/- 12.8 to 64.05 +/- 13.5 pg mL-1), and in serum cortisol (P = 0.05) compared to its baseline values (8.98 +/- 3.2 microgr dL-1 vs. 6.57 +/- 2.3 microgr dL-1, respectively).

CONCLUSION

In our experimental model, coronary vessel wall injury-activated CRH/ACTH/cortisol axis caused a significant increase in plasma CRH, cortisol and cellular cAMP levels, which may influence the response of coronary arteries to injury.

Early introduction of cereals into children's diets as a risk-factor for grass pollen asthma

BACKGROUND

The prevalence of asthma has increased from the 1950s to the 1990s. The relationship between diet and asthma is an area of controversy that has never been fully evaluated. Attempts at dietary prevention of asthma have produced conflicting results. We have recently identified allergens from cereals that show cross-reactivity with proteins in grass pollen. An early intake of cereals in the diet during early life might cause IgE sensitization to cereals. It is not known whether such sensitization predisposes the development of allergy to pollen.

METHODS

To test this hypothesis, a cross-sectional study and an observational case-control analysis of reviewed data were carried out on 16381 patients who had been admitted to our Allergy Unit between 1989 and 1999. All the patients underwent allergy tests to identify asthma risk-factors. All information in our data base was analysed using the SPSS computer system.

RESULTS

There has been an increase of 7.8% in incidences of allergic asthma and a 7.3% increase in asthma due to grass pollen in the last decade. Grass-pollen asthma was associated with sensitization to cereals. The early introduction of cereals in the diet of children was found to be a risk factor for grass-pollen asthma (OR = 5.95; 95% CI 3.89-9.10).

CONCLUSIONS

These findings document the progression of allergic asthma during a decade in a large sample of people who were influenced by similar environmental conditions and studied with the same diagnostic methods. This study represents the largest database of patients in which a common food is shown to be a risk factor for asthma.

[Effect of cAMP on the function of endothelial cells and fibromuscular proliferation after the injury of the carotid and coronary arteries in a porcine model]

INTRODUCTION AND OBJECTIVE

Reendothelization of damaged blood vessels protects against the vascular injury response. We evaluated in vivo whether a systemic increase in cAMP accelerates reendothelization and attenuates intimal hyperplasia in injured swine carotid and coronary arteries.

METHODS

Both carotid arteries of 10 swines were subjected to balloon injury. Five animals had been treated with 2 ml (10 mg) of Forskolin, an activator of the adenylate cyclase, and another 5 with 2 ml of saline solution. These animals were sacrificed at day 8, and carotid artery reendothelization was evaluated. The descendent coronary (DC) artery of another 19 pigs was injured by atherotome. Nine animals had been treated with 2 ml of Forskolin, and another 10 with 2 ml of saline solution. These animals were sacrificed at day 28, with myointimal proliferation and arterial geometric remodelation being evaluated. Likewise, in these animals intracellular cAMP levels were measured at baseline and 28 and 60 minutes after saline solution or Forskolin administration and 90 min after arterial injury.

RESULTS

Eight days after balloon injury, carotid artery reendothelization was greater in the Forskolin-treated group compared with the control group (p = 0.02), and the number of CD31 positive cells was statistically increased in the treated group (38 +/- 11 cells) versus controls (11 +/- 9 cells). Although the degree of vascular injury caused by atherotome was similar in all of the arteries in the control group, restenosis was only observed in 40% of these animals. Correlation analysis demonstrated that intracellular cAMP may condition arterial geometric remodeling and the diameter of the lumen after vascular injury.

CONCLUSION

Our results suggest that cAMP may promote reendothelization and attenuate fibromuscular proliferation.

Acute stent thrombosis visualized by intravascular ultrasound

Subacute stent thrombosis is currently a rare but feared complication in patients undergoing coronary intervention. Intravascular ultrasound is a useful technique to guide stent implantation. However, its value in patients suffering from acute stent thrombosis has not been described. Herein, we present the intravascular ultrasound findings of a patient experiencing ongoing stent thrombosis and impending vessel closure.

Initial results and long-term clinical and angiographic outcome of coronary stenting in women

To assess whether gender influences the results of coronary stenting, 158 consecutive women undergoing coronary stenting were compared with 823 consecutive men. Women had more adverse baseline characteristics, a higher hospital mortality, and were independently associated with procedural failure/complications (relative risk 2.4, 95% confidence interval 1.2 to 4.8); however, the long-term event-free survival and the restenosis rate were not influenced by gender.

Fate of stent-related side branches after coronary intervention in patients with in-stent restenosis

OBJECTIVES

We sought to assess the fate of stent (ST)-related side branches (SB) after coronary intervention in patients with in-ST restenosis.

BACKGROUND

In-ST restenosis constitutes a therapeutic challenge. Although the fate of lesion-related SB after conventional angioplasty or initial coronary stenting is well established, the outcome of ST-related SB in patients with in-ST restenosis undergoing repeat intervention is unknown.

METHODS

One hundred consecutive patients (age 61 +/- 11 years, 22 women) undergoing repeat intervention for in-ST restenosis (101 ST) were prospectively studied. Two hundred and twenty-six SB spanned by the ST were identified. The SB size, type, ostium involvement, location within the ST and take-off angle were evaluated. The SB TIMI (Thrombolysis in Myocardial Infarction trial) flow grade was studied in detail before, during, immediately after the procedure, and at late angiography.

RESULTS

Occlusion (TIMI flow grade = 0) was produced in 24 (10%) SB, whereas some degree of flow deterioration (> or = 1 TIMI flow grade) was observed in 57 SB (25%). The SB occlusion was associated with non-Q wave myocardial infarction in two patients (both had large and diseased SB). Side-branch occlusion at the time of initial stenting (RR [relative risk] 11.1, 95% CI [confidence interval] 3.5-35.5, p < 0.001), diabetes (RR 3.5, 95% CI 1.1-10.5, p = 0.02), SB ostium involvement (RR 5.0, 95% CI 1.4-17.2, p = 0.004), baseline SB TIMI flow grade <3 (RR 5.5, 95% CI 1.7-18.1, p = 0.005), and restenosis length (RR 1.05 95% CI 1.01-1.11, p = 0.03) were identified as independent predictors of SB occlusion. Late angiography in 19 initially occluded SB revealed that 17 (89%) were patent again. The long-term clinical event-free survival (81% vs. 82% at two years) in patients with and without initial SB occlusion was similar.

CONCLUSIONS

Occlusion or flow deterioration of SB spanned by the ST is relatively common during repeat intervention for in-ST restenosis. Several factors (mainly anatomic features) are useful predictors of this event. However, most SB occlusions are clinically silent and frequently reappear at follow-up.

Guidewire-induced coronary pseudostenosis as a source of error during physiological guidance of stent deployment

Coronary pseudostenoses are a known result of the interaction between tortuous vessels and guidewires and are generally handled by the interventionalist as inocuous side effects of intracoronary instrumentation. The present report demonstrates that pseudostenosis may have hemodynamic relevance and may constitute an important source of error when physiological guidance of percutaneous procedures is performed using sensor-tipped guidewires.

Pressure wire kinking, entanglement, and entrapment during intravascular ultrasound studies: a potentially dangerous complication

The simultaneous use of intravascular ultrasound catheters and sensor-tipped guidewires is gaining acceptance during coronary interventions as a means to gain further insights on the significance of coronary stenoses. Herein we describe four patients in whom the distal tip of the pressure wire became entrapped during an intravascular ultrasound examination. In the four patients, a localized kinking of the pressure wire initially prevented the removal of the imaging catheter and eventually the wire-catheter assembly had to be retrieved as a unit into the guiding catheter. In one patient, unraveling of the distal part of the pressure wire was noticed. In two patients, a complete loop with further kinking of the pressure wire was induced during the maneuvers performed to withdraw the imaging system. Three patients experienced transient angina. Although in our patients this technical problem was not associated with any clinical sequelae, interventional cardiologists should be aware of the potential complications associated with the combined use of these two intracoronary diagnostic tools.

[Guidelines of the Spanish Society of Cardiology on aortic diseases]

Acute aortic pathology is an urgent clinical situation, of which prognosis mainly related to prompt and accurate diagnosis as well as a quick treatment. In this paper we review the aortic pathology, specially focused on aortic dissection. We review its etiology, clinical presentation and diagnostic methods. In addition the medical therapy and the surgical indications of aortic aneurysm, dissection and aortic intramural haematoma are described.

Propensity and mechanisms of restenosis in different coronary stent designs: complementary value of the analysis of the luminal gain-loss relationship

OBJECTIVES

This study sought to investigate the influence of stent design on the long-term angiographic outcome.

BACKGROUND

The proportional relationship between vessel injury and late luminal loss in percutaneous revascularization should be best appreciated in coronary stenting, where recoil and shrinkage are theoretically minimal. It is unclear whether all stent designs can counterbalance this reactive loss by achieving a large initial luminal gain (bigger is better).

METHODS

In 523 lesions successfully stented, the long-term angiographic results of slotted-tube (n = 331), coil (n = 85), multicellular (n = 70) and self-expandable mesh (n = 37) stent designs were compared using the angiographic gain-loss relationship (GLR).

RESULTS

Restenosis rate was 10% for multicellular, 20% for slotted-tube, 46% for coil and 49% for self-expandable designs (p = 0.001). At a difference with other designs, no significant GLR was found in coil stents, suggesting additional mechanisms of luminal loss (i.e., plaque protrusion, stent compression) to neointimal proliferation. Significant differences in late loss between stents were found within each quartile of luminal gain, suggesting a specific role of design in luminal loss. Multivariate analysis identified use of coil and self-expandable stents, vessel size, minimal luminal diameter preintervention, luminal gain and stent length as variables with independent predictive value for several indices of angiographic long-term outcome.

CONCLUSIONS

The analysis of GLR: 1) demonstrates that stent design influences late luminal loss; 2) challenges the applicability of the widely accepted "bigger is better" approach to all stent designs; and 3) appears as a valuable tool in assessing long-term stent performance.

Long-term angiographic results of stenting in chronic total occlusions: influence of stent design and vessel size

BACKGROUND

Although coronary stenting has decreased the high restenosis rate associated with percutaneous transluminal coronary angioplasty of chronic total occlusions (CTOs), the results are still less satisfactory than those found in nonoccluded lesions, at least as reported with the Palmaz-Schatz stent. The present work compares the restenosis rate of other stent designs with that of the Palmaz-Schatz stent.

METHODS

We studied the long-term angiographic outcome of 120 CTOs successfully recanalized with balloon-expandable stents and without concomitant debulking techniques. Angiographic follow-up and full quantitative coronary angiography analysis was prospectively performed in all patients. Three different stent designs were compared: Palmaz-Schatz (n = 47), coil (n = 24), and multicellular (n = 49). Particular attention was paid to their performance in vessels of 3 mm or less and greater than 3 mm in diameter. Restenosis was defined as a 50% or greater diameter stenosis at follow-up.

RESULTS

Multicellular stents were implanted more frequently in the left anterior descending artery and in patients with multivessel disease. No other significant differences in clinical or angiographic baseline characteristics, including vessel size, were noted between groups. At follow-up, multicellular stents presented a lower restenosis rate (22% vs 36% and 58% in the Palmaz-Schatz and coil stent groups, respectively; P =.01 ) and larger minimal luminal diameters (1.92 +/- 0.85 mm vs 1.73 +/- 0.98 and 1.38 +/- 0.83 mm in the Palmaz-Schatz and coil stent groups, respectively; P = 0.0). The superiority of the multicellular stent design resulted from a lower restenosis rate in vessels of 3.0 mm or less in diameter (20% vs 47% and 79% in the Palmaz-Schatz and coil stent groups, respectively; P =.006).

CONCLUSIONS

These results suggest that the restenosis rate after stent recanalization of CTOs is influenced by both stent design and vessel size and may indicate a superiority of multicellular over Palmaz-Schatz and coil stent designs for this purpose.

Results (>6 months) of stenting of >1 major coronary artery in multivessel coronary artery disease

Multivessel percutaneous transluminal coronary angioplasty (PTCA) is associated with a high requirement for further revascularization procedures. Although stenting can reduce restenosis and clinical events after 1-vessel intervention, little information is available after multivessel coronary stenting. We followed up 136 patients (9% of 1,481 undergoing stenting in our center) who had had stent implantation in at least 2 different major native coronary arteries and were followed-up for >6 months. Each patient had received a mean of 2.3 +/- 0.6 stents (1.13 +/- 0.4 stents per lesion) and procedural success was 95%. In-hospital complications included 1 death, 1 Q-wave infarction, 5 non-Q-wave myocardial infarctions, and 1 repeat PTCA. After a mean of 18 +/- 13 months, 7 patients died (3 of heart failure, 4 of noncardiac causes), 2 required coronary bypass surgery, 1 had a myocardial infarction, 13 target vessel repeat PTCA, and 4 non-target vessel PTCA. Survival free of major cardiac events was 75% at 3 years. A history of heart failure, dilation of a restenotic lesion, and 3-vessel dilation were independent negative predictors of event-free survival. Angiographic follow-up was available in 86 patients: 56 (65%) were restenosis free, 23 (27%) had 1-vessel restenosis, and 6 (7%) had 2-vessel and 1 patient 3-vessel restenosis. Restenosis per vessel was 23% (41 of 177). Reference diameter, past-PTCA minimal luminal diameter, and length of the stent were independent predictors of restenosis. We conclude that multivessel stenting provides good midterm results in selected patients with multivessel coronary artery disease. Midterm events are less frequent than previously reported after balloon PTCA.

Initial results and long-term clinical and angiographic implications of coronary stenting in elderly patients

Results of 378 consecutive elderly patients (> or = 65 years) undergoing coronary stenting were compared with those of 601 younger patients. Although the restenosis rate was similar in the 2 groups, age > or = 65 years was an independent predictor of in-hospital mortality (relative risk 5.4, 95% confidence interval 1.2 to 20.1) and follow-up mortality (relative risk 2.8, 95% confidence interval 1.3 to 6.1).

Long-term outcome and determinants of event-free survival in patients treated with balloon angioplasty for in-stent restenosis

Long-term prognosis and predictors of event-free survival were studied in 56 consecutive patients with in-stent restenosis successfully treated with balloon angioplasty. Most patients sustained prolonged clinical benefit, but during follow-up, those with diabetes or with a short time interval (<4 months) from stenting to repeat angioplasty experienced adverse cardiac events more often.

Long-term clinical and echocardiographic follow-up after percutaneous mitral valvuloplasty with the Inoue balloon

BACKGROUND

The objective of this study was to assess the long-term clinical outcome and valvular changes (area and regurgitation) after percutaneous mitral valvuloplasty (PMV).

METHODS AND RESULTS

After PMV, 561 patients were followed up for 39 (+/-23) months and clinical/echocardiographic data obtained yearly. Kaplan-Meier and Cox regression analyses were performed to estimate event-free survival, its predictors, and the relative risks of several patient subgroups. There were several nonexclusive events: 19 (3.3%) cardiac deaths, 55 (9.8%) mitral replacements, 6 (1%) repeated PMVs, 56 (10%) cases of restenosis, and 108 (19%) cases of clinical impairment. Survival free of major events (cardiac death, mitral surgery, repeat PMV, or functional impairment) was 69% at 7 years, ranging from 88% to 40% in different subgroups of patients. Wilkins score was the best preprocedural predictor of mitral opening, but the procedural result (mitral area and regurgitation) was the only independent predictor of major event-free survival. Mitral area loss, though mild [0.13 (+/-0.21)cm2], increased with time and was >/=0.3 cm2 in 12%, 22%, and 27% of patients at 3, 5, and 7 years, respectively. Regurgitation did not progress in 81% of patients, and when it occurred it was usually by 1 grade.

CONCLUSIONS

Seven years after PMV, more than two thirds of patients were in good clinical condition and free of any major event. The procedural result was the main determinant of long-term outcome, although a high score had also negative implications. Mitral area decreased progressively over time, whereas regurgitation did not tend to progress.

Aortic dissection occurring during coronary angioplasty: angiographic and transesophageal echocardiographic findings

A localized acute aortic dissection was produced in 2 patients, complicating coronary angioplasty. In both cases a coronary dissection provided the entry door, with subsequent retrograde progression of the dissection into the aortic root. After sealing the entry door, both patients could be managed conservatively using transesophageal echocardiography to accurately define the location of the intimal flap and to rule out dissection progression.

Clinical and angiographic implications of balloon rupture during coronary stenting

Balloon rupture was detected in 66 consecutive patients (5.8%) during coronary stenting. This rare phenomenon usually does not have clinical or angiographic sequelae, but in some cases, it may induce new coronary dissections that can be managed with additional stenting, but also may cause clinical complications.

Angioscopic evaluation of angiographically complex coronary lesions

Coronary angioscopy (CA) provides direct visualization of the endoluminal surface of coronary vessels. The usefulness of CA during coronary angioplasty of angiographically complex lesions remains to be established. This study was designed to determine the value of CA to elucidate the underlying substrate of angiographically complex lesions. Forty-seven consecutive patients with angiographically complex lesions were studied with CA before coronary intervention. Mean age of the group was 59 +/- 9 years; six patients were women. Forty (85%) patients had unstable angina. Complex angiographic lesions included coronary occlusions (n = 23) (14 with Thrombolysis in Myocardial Infarction coronary flow grade 0 and nine with flow grade 1), lesions with intraluminal filling defects suggestive of thrombus or ulceration (n = 8), and lesions that were highly eccentric (n = 16). Items analyzed with CA included red thrombus (lining or protruding) and plaque color (yellow, white, or mixed). In all patients, CA visualized the protruding material causing the angiographic appearance. At this site CA detected red thrombus in 34 (72%) patients (14 protruding, 20 lining) and atherosclerotic plaque in 45 (96%) patients. At the site of the angiographically complex lesion, plaque was classified as predominantly yellow in 24 patients, mixed in 12, and white in nine. The incidence of thrombus on CA was higher for occluded vessels (91%) or lesions with intraluminal filling defects or ulceration (87%) than in eccentric lesions (37%) (p < 0.05). However, plaque coloration was not significantly different among these three angiographic subgroups. Initial procedural success (without stent requirement) was lower in lesions showing protruding thrombus on CA (64% vs 91 %, p < 0.05). Thus most angiographically complex lesions contain thrombus. On CA red thrombus was more frequently identified on occluded vessels and lesions with filling defects or ulceration than in eccentric lesions. Yellow or mixed plaques are common in these patients, suggesting lipid-laden plaques as the underlying pathologic substrate of angiographically complex lesions.

Angioscopic characteristics of coronary narrowing in patients with recurrent myocardial ischemia after myocardial infarction

Coronary angioscopy was used to elucidate the underlying substrate of the culprit lesion in 20 patients with postinfarction ischemia and in 19 patients with other types of unstable angina. Plaque characteristics were similar in both groups, but red thrombi and occlusive thrombi were more frequently seen in patients with postinfarction ischemia.

Clinical and angiographic implications of coronary stenting in thrombus-containing lesions

OBJECTIVES

This study sought to determine the results of coronary stenting in thrombus-laden lesions.

BACKGROUND

The angiographic evidence of intracoronary thrombus has classically been considered a formal contraindication to stent implantation. However, with increasing use of stenting, the indications for this technique have widened to include treatment of patients who have an acute coronary syndrome or lesions with adverse anatomic features.

METHODS

We studied 86 consecutive patients (mean age +/- SD 61 +/- 11 years, 14 women) undergoing coronary stenting of a thrombus-containing lesion; the procedure was performed electively in 39% and after angioplasty failure in 61%. Sixty-four patients (75%) were treated for unstable angina, and 19 (22%) underwent the procedure during an acute myocardial infarction. A specific protocol that included clinical and late angiographic follow-up was used.

RESULTS

Angiographic success was obtained in 83 patients (96%). Five patients (6%) died during the hospital stay despite angiographic success; four of these had cardiogenic shock, and one (1%) had subacute stent thrombosis. Non-Q wave myocardial infarction developed in five additional patients (6%), and four of these five had data consistent with distal embolization. Of the 78 patients discharged with angiographic success, 67 (86%) were event-free and clinically improved at last follow-up visit (12 +/- 11 months). During the follow-up period, eight patients required repeat angioplasty, one patient required heart transplantation, and two patients died. Quantitative angiography demonstrated excellent angiographic results after stenting (minimal lumen diameter 0.31 +/- 0.4 vs. 2.77 +/- 0.6 mm). Late angiographic follow-up (5.5 +/- 1 months) was obtained in 50 patients with 54 lesions (93% of eligible), revealing a minimal lumen diameter of 2.0 +/- 1 mm and restenosis (lumen narrowing > 50%) in 18 lesions (33%).

CONCLUSIONS

Coronary stenting constitutes an effective therapeutic strategy for patients with thrombus-containing lesions, either after failure of initial angioplasty or electively as the primary procedure. Coronary stenting in this adverse anatomic setting results in a high degree of angiographic success, a low incidence of subacute thrombosis and an acceptable restenosis rate.

Intracoronary ultrasound before coronary interventions: a prospective comparison of two different catheters

Intravascular ultrasound (IVUS) provides unique information about the coronary arterial wall that can be used to guide transcatheter therapy. In this prospective study, two different IVUS systems were compared with respect to feasibility of imaging before intervention and angiographic changes induced by the simple advancement of the catheter across the lesion. Eighty-five patients (mean age 59 +/- 10 yr, 11 female) were studied with IVUS before intervention. In 34 patients, a 4.8 F (1.6-mm) IVUS catheter was used (Group I), whereas in the remaining 51 patients, a 3.5 F (1.2-mm) IVUS catheter was used (Group II). Quantitative angiography was performed before and after the IVUS study to determine potential changes in lumen diameter. Clinical and angiographic characteristics were similar in the two groups. A successful IVUS interrogation of the target lesion was obtained more frequently in Group II (45/51 (88%) vs. 19/34 (56%) patients, P < 0.01). After the IVUS study, a change in minimal lumen diameter was seen in Group I (baseline 0.84 +/- 0.2 vs. final 1.17 +/- 0.2 mm, P < 0.001) and Group II patients (baseline 0.80 +/- 0.3 vs. final 1.03 +/- 0.4 mm, P < 0.01). In the 64 lesions successfully crossed, the absolute gain in lumen diameter was significantly higher in Group I (0.40 +/- 0.2 vs. 0.23 +/- 0.2 mm, P < 0.05). In addition, an inverse correlation was found between baseline minimal lumen diameter and the absolute lumen gain induced by the IVUS study in Group I (r = -0.47, P < 0.05) but not in Group II patients (r = -0.16, NS). Neither angiographic nor echogenic lesion characteristics were associated with the change in lumen diameter. When multivariate analysis was applied, catheter size was the only independent predictor of lumen gain induced by IVUS after adjustment. Thus, the advancement of IVUS catheters across severe coronary lesions induces significant angiographic changes consistent with plaque remodeling and a Dotter effect. The use of smaller catheters not only allows a higher number of lesions to be studied before intervention, but also lessens the mechanical disruption of the plaque, yielding a more accurate and veracious picture of baseline plaque characteristics.

[The role of non-angiographic observations (IVUS, angioscopy, doppler) in coronary stenting]

Coronary stenting is increasingly used during transcatheter coronary therapy. Coronary angiography, mainly since the advent of quantitative angiography, provides an effective tool to obtain excellent clinical results with coronary stenting. However, during this procedure some limitations inherent to the angiographic techniques may become apparent. Accordingly, great enthusiasm has been generated regarding the potential value of alternative diagnostic techniques to guide coronary stenting. Intravascular ultrasound is able to study the arterial wall and provides a unique tool to assess stent expansion, apposition and symmetry. Therefore, this technique is increasingly used to optimize stent deployment. Coronary angioscopy directly visualizes stent expansion and is able to precisely recognize protrusion of redundant fronds of tissue or residual dissections within the stent struts. In addition, this technique is the procedure of choice to identify intracoronary thrombus. Intracoronary Doppler permits the application in the catheterization laboratory of sophisticated methods of functional assessment of lesion severity. Coronary stenting allows a faster and complete normalization of coronary flow reserve than balloon angioplasty. Thus, all these new techniques of intracoronary diagnosis provide unique and useful information, which is complementary to that obtained with angiography, potentially useful during coronary stenting.

Arterial perforation during optimization of coronary stents using high-pressure balloon inflations

Angiographic optimization of coronary stents, using high-pressure balloon inflation, was complicated by vessel rupture in 3 patients. The risk of this potentially life-threatening complication should be considered during stent optimization.

Percutaneous mitral valvuloplasty for rheumatic mitral stenosis associated with cor triatriatum

A patient with rheumatic mitral stenosis associated with cor triatriatum is described. The anomalies were detected by two-dimensional echocardiography and confirmed by transesophageal echocardiography. Percutaneous mitral valvuloplasty was successfully performed with the inoue technique. The clinical and technical implications during the procedure of this previously unreported association are discussed.

Stent embolization during intracoronary stenting

Nine patients with systemic embolization complicating intracoronary stenting (incidence 1.8%) are described. Although this rare complication was not associated with any clinical sequelae, great care should be taken to prevent this possibility, especially in patients with unfavorable anatomic characteristics, including lesions in the left circumflex artery, at bend points, and calcified lesions.

Percutaneous mitral valvuloplasty with the Inoue technique in a patient with heavily calcified interatrial septum

A 75-year-old woman with severe rheumatic mitral stenosis was admitted for percutaneous mitral valvuloplasty. Two-dimensional echocardiography disclosed severe calcification of the posterolateral left atrial wall and interatrial septum. Percutaneous mitral valvuloplasty, using the inoue technique, was successfully performed after a transseptal puncture through the calcified interatrial septum, avoiding the need for surgical intervention.

[Coronary angioscopy: initial experience during coronary interventions]

BACKGROUND AND OBJECTIVE

Percutaneous coronary angioscopy (CAG) provides in vivo visual information about the luminal aspect of the vessel. In this report we describe our initial experience with CAG during coronary angioplasty (PTCA).

METHODS

Fifty-five patients (age 60 +/- 9 years), 8 female, were included. Most patients, 42 (76%) were treated for unstable angina.

RESULTS

In 49 patients (89%) CAG was performed prior to PTCA, and in all cases the intraluminal material responsible of the stenosis was recognized. This included plaque associated to thrombus in 29 patients (59%), isolated plaque in 15 (31%) and isolated thrombus in 5 (10%). Of these plaques, 25 (57%) were yellow, 14 (32%) were yellow and white and 5 (11%) were white. Of the 34 thrombi, 23 (68%) were mural and 11 (32%) protruding. CAG post-PTCA was performed in 43 patients (78%). CAG visualized residual plaque in 41 patients (95%) and residual thrombus in 34 (79%). In addition, CAG recognized dissections in 30 patients (70%). CAG was more sensitive than angiography for the detection of thrombus (pre-PTCA 34 [69%] vs 11 [22%]; p < 0.05, and post-PTCA 34 [79%] vs 5 [12%]; p < 0.05]) and coronary dissections (post-PTCA 30 [70%] vs 19 [44%]; p < 0.05). CAG before intervention caused angina in 39 patients (80%), ventricular fibrillation (successfully managed with DC cardioversion) in 1, and AV block in another patient. The angiographic result deteriorated in 4 patients (9%) immediately after the CAG performed following PTCA. A repeat balloon PTCA was required in these patients.

CONCLUSIONS

CAG provides unique information on coronary lumen surface that complements angiographic data. As compared with angiography, CAG is more sensitive in the detection of intracoronary thrombi and dissections. Further studies are required to determine whether the additional information provided by CAG may be used, to select coronary interventions according to specific lesion characteristics, to optimize dilation results and, eventually, to improve the clinical outcome of these patients.

Findings of coronary angioscopy in angiographically normal coronary segments of patients with coronary artery disease

Compared with pathologic studies coronary angiography is a relatively insensitive technique to detect early atherosclerosis. Coronary angioscopy is a new technique providing direct information on luminal vessel surface. To determine whether coronary angioscopy may detect the presence of atherosclerotic disease on angiographically normal coronary segments, 52 patients underwent a study with coronary angioscopy before coronary angioplasty. The mean age was 59 +/- 10 years; 46 patients were men and 6 were women. The reason for coronary angioplasty was unstable angina in 36 patients, stable angina in 8 patients, and silent ischemia in 8 patients. In seven patients angiography revealed luminal irregularities on the coronary segment proximal to the culprit lesion, and all these patients also had proximal disease as demonstrated by coronary angioscopy. In the remaining 45 (87%) patients angiography revealed a smooth-vessel contour proximal to the target lesion. On quantitative angiography these "normal" coronary segments measured 2.8 +/- 0.4 mm in luminal diameter. In 30 (67%) of these patients angioscopy revealed proximal disease on the vessel wall, but in 15 (33%) patients the luminal surface of these segments also appeared normal on angioscopy. Disease as detected by angioscopy in angiographically normal segments included yellow plaque in 19 patients, mural thrombus in 5, mixed plaques in 4, and small flaps in 2 patients. In eight patients coronary angioscopy detected that atherosclerotic disease extended proximally from the target lesion, but in the remaining 22 patients the angioscopic findings appeared to be discrete and well separated from the angiographic lesion. All these plaques were relatively small and did not protrude into the coronary lumen.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioscopic findings during coronary angioplasty of coronary occlusions

OBJECTIVES

This study sought to elucidate angioscopic findings in totally occluded vessels before and after intervention.

BACKGROUND

Coronary angioscopy allows direct visualization of the lumen surface of the coronary arteries; however, the utility of coronary angioscopy during coronary angioplasty of vessels with a total occlusion is unknown.

METHODS

Twenty-one consecutive patients (mean [+/- SD] 58 +/- 9 years, range 39 to 77; 3 women, 18 men) undergoing dilation of an occluded vessel were studied with coronary angioscopy. Occlusions were classified as functional in 8 patients (Thrombolysis in Myocardial Infarction [TIMI] flow grade 1) and anatomic in 13 (TIMI flow grade 0). Once the guide wire had crossed the occlusion, coronary angioscopy was attempted before and after angioplasty.

RESULTS

In all patients, coronary angioscopy before dilation visualized protruding material occluding the coronary lumen where the guide wire was wedged. The occlusion consisted of red thrombus in 19 patients (90%) (2 with isolated occlusive thrombus, 17 with thrombus associated with atherosclerotic plaque) and protruding yellow plaque in 2 patients (10%). However, on angiography only 7 occlusions (33%) had data consistent with thrombus (p < 0.01 vs. coronary angioscopy). Successful dilation was obtained in 20 patients. After dilation, coronary angioscopy was repeated in 18 patients, revealing residual thrombus with plaque in 16 (89%) and a residual yellow plaque in 2. In addition, coronary angioscopy revealed coronary dissections in 13 patients (72%); however, angiography revealed dissections only in 10 patients (55%) and residual thrombus in 2 (10%) (p < 0.001). In one patient, coronary angioscopy visualized silent distal embolization of a red thrombus not previously recognized on angiography.

CONCLUSIONS

Before intervention, coronary angioscopy provides unique insights into the pathologic substrate of occluded coronary vessels. An occlusive plaque with thrombus is the most common underlying substrate in these lesions. After successful dilation, angiographically silent mural thrombus is seen in most patients. This information could be used to assist in the selection of candidates and type of coronary interventions and could also prove to be of prognostic value in patients with occluded vessels.

Coronary stenting for acute coronary dissection after coronary angioplasty: implications of residual dissection

OBJECTIVES

The aim of this study was to assess the implications of residual coronary dissections after stenting.

BACKGROUND

Coronary stenting is currently used in selected patients with coronary dissection after angioplasty. However, in some patients the total length of the dissection may not be completely covered with the device.

METHODS

Forty-two consecutive patients (mean [+/- SD] age 58 +/- 11 years; 39 men, 3 women) undergoing stenting for a major coronary dissection after angioplasty were studied.

RESULTS

Thirty (67%) coronary dissections were small (< or = 15 mm), and 29 (64%) were occlusive (Thrombolysis in Myocardial Infarction [TIMI] flow grade < or = 2). In 3 patients, coronary stenting was unable to open large occlusive dissections, but a good angiographic result was obtained in 39 patients (93%). After stenting, 22 of these patients (56%) had no visible residual dissections, and 13 (33%) had small and 4 (10%) had large residual dissections. These residual dissections were stable and did not compromise coronary flow. In a repeat angiogram (24 h later) the stent was patent in all 39 patients. However, two patients experienced a subacute stent occlusion. Of the remaining 37 patients, 36 (97%) had a late angiogram after stenting. Quantitative angiography revealed a reduction in minimal lumen diameter at the stent site (2.6 +/- 0.4 vs. 2 +/- 0.7 mm, p < 0.05) and a trend toward improvement in vessel diameter at the site of the previous residual dissection (1.7 +/- 0.6 vs. 1.9 +/- 0.5 mm, p < 0.1). The angiographic image of residual dissection disappeared in all patients. These factors provided a rather smooth angiographic appearance at follow-up. The four patients with large residual dissections after stenting did not have restenosis and were asymptomatic at last visit.

CONCLUSIONS

Coronary stenting is effective in the management of acute coronary dissections after angioplasty. In this setting, small residual dissections are frequently seen but have a good outcome and disappear at follow-up. Large residual dissections may have a good outcome if coronary flow is not impaired and no residual stenosis is visualized.

Angiographic changes (Dotter effect) produced by intravascular ultrasound imaging before coronary angioplasty

Intravascular ultrasound (IVUS) imaging of the coronary arteries has recently been introduced for the study of coronary lesions, but the angiographic effects produced by an IVUS examination before coronary angioplasty are unknown. Accordingly, the feasibility of and the potential angiographic changes caused by IVUS study (4.8F catheter) of severe coronary lesions was prospectively studied. Thirty consecutive coronary lesions were analyzed before intervention (29 patients, mean age 61 +/- 9 years, 5 women and 24 men). Before and after IVUS examination, intracoronary nitroglycerin 0.2 mg, was administered and two orthogonal angiographic views obtained. In 17 (57%) lesions the transducer of the IVUS catheter (radiopaque) could be gently advanced for precise location at the lesion site, and in every case the ultrasonic images revealed that the catheter was wedged into the plaque. In the remaining 13 lesions only the catheter tip but not the transducer could be located at the lesion site. Baseline minimal luminal diameter was similar in the crossed lesions and in lesions that prevented complete advancement of the IVUS catheter (0.86 +/- 0.2 vs 0.82 +/- 0.2 mm, difference not significant). Lesion characteristics could not predict the feasibility of the IVUS study. No complications resulted from the IVUS study. Quantitative angiography (automatic edge-detection system) revealed a significant increment in minimal luminal diameter (0.84 +/- 0.2 vs 1.16 +/- 0.3 mm, p < 0.001) and minimal luminal cross-sectional area (0.67 +/- 0.4 vs 1.09 +/- 0.5 mm2, p < 0.01) after passage of the IVUS catheter.(ABSTRACT TRUNCATED AT 250 WORDS)

Determinants of coronary compliance in patients with coronary artery disease: an intravascular ultrasound study

OBJECTIVES

The aim of this study was to elucidate determinants of coronary compliance in patients with coronary artery disease.

BACKGROUND

Intravascular ultrasound potentially enables in vivo evaluation of coronary artery compliance.

METHODS

Twenty-seven patients (mean age [+/- SD] 57 +/- 11 years, three women) undergoing coronary angioplasty were studied with intravascular ultrasound imaging. A mechanical intravascular ultrasound system (4.8F, 20 MHz) was used. A total of 58 different coronary segments (proximal to the target angiographic lesion) were studied. Of these, 35 were located in the left anterior descending, 9 in the left main, 8 in the left circumflex and 6 in the right coronary arteries. During intravascular ultrasound imaging, 22 segments (38%) appeared normal, but 36 (62%) had plaque (24 fibrotic, 3 lipidic and 9 calcified). Systolic-diastolic changes in area (delta A) and pressure (delta P) with respect to vessel area (A) were used to study normalized compliance (Normalized compliance = [delta A/A]/delta P [mm Hg-1 x 10(3)]).

RESULTS

Lumen area and plaque area were 12.6 +/- 5.7 and 3 +/- 3 min2, respectively. Plaque was concentric (more than two quadrants) at 10 sites, but the remaining 26 plaques were eccentric. Compliance was inversely related to age (r = -0.34, p < 0.05) but was not related to other clinical variables. Compliance was greater in the left main coronary artery (3.9 +/- 2.1 vs. 1.8 +/- 1.2 mm Hg-1, p < 0.05) and in coronary segments with normal findings on ultrasound imaging (2.9 +/- 1.9 vs. 1.6 +/- 1.1 mm Hg-1, p < 0.01). Moreover, at diseased coronary segments compliance was lower in calcified plaques than in other types of plaques (1.2 +/- 0.7 vs. 2.3 +/- 1.6 mm Hg-1, p < 0.01) but was similar in concentric and eccentric plaques (1.6 +/- 1.5 vs. 1.6 +/- 0.9 mm Hg-1). Plaque area (r = -0.38, p < 0.01) was inversely correlated with compliance. On multivariate analysis, only age and plaque area were independently related to compliance.

CONCLUSIONS

Intravascular ultrasound may be used to evaluate compliance in patients with coronary artery disease. Compliance is reduced with increasing age and is mainly determined by the arterial site and by the presence, size and characteristics of plaque on intravascular ultrasound imaging.

Percutaneous mitral valvuloplasty with severe pulmonary artery hypertension

The aim of this study was to assess the initial and midterm outcome of patients with severe pulmonary hypertension undergoing percutaneous mitral valvuloplasty (PMV). Accordingly, the baseline characteristics, immediate results and follow-up of 64 consecutive patients with severe pulmonary artery hypertension (systolic pulmonary artery pressure > or = 60 mm Hg on cardiac catheterization) (group I) were analyzed and compared with those of 194 consecutive patients with lower pulmonary pressures (group II). Patients in group I were more symptomatic (New York Heart Association functional class > or = III, 72 vs 40%, p < 0.001) and had higher echocardiographic scores (8.6 +/- 2 vs 7.4 +/- 1, p < 0.05). Before PMV, mitral gradient was higher (17 +/- 6 vs 13 +/- 5 mm Hg, p < 0.025) and mitral valve area smaller (0.79 +/- 0.2 vs 0.96 +/- 0.2 cm2, p < 0.005) in group I patients, who also had higher pulmonary vascular resistances (469 +/- 299 vs 157 +/- 125 dynes s-1 cm-5, p < 0.005). On multivariate analysis patients in group I were more symptomatic, had smaller mitral valve areas and higher mitral gradients. PMV success (area gain > 50% without complications) was similar (89 vs 87%) in both groups. After PMV final mitral gradient (5 +/- 2 vs 4 +/- 2 mm Hg) and area (1.82 +/- 0.5 vs 1.87 +/- 0.5 cm2) were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Early and late results of percutaneous mitral valvuloplasty for mitral stenosis associated with mild mitral regurgitation

To assess the influence of mild mitral regurgitation (MR) on the initial and long-term results of percutaneous mitral valvuloplasty (PMV), the baseline characteristics, early results and follow-up of 102 consecutive patients with mild MR before PMV (group I) were prospectively analyzed and compared with those of 186 consecutive patients without MR (group II). Age, gender and symptomatic status were similar in both groups, but more patients in group I were in atrial fibrillation (70 vs 54%, p < 0.05) and had had a previous episode of pulmonary edema (25 vs 14%, p < 0.05). On echocardiography, patients in group I had larger left atria (58 +/- 12 vs 53 +/- 10 mm, p < 0.05) and more calcified mitral valves (score 1.9 +/- 0.8 vs 1.5 +/- 0.7, p < 0.05), but the total echocardiographic score (8.0 +/- 2 vs 7.3 +/- 2) was similar in both groups. Baseline hemodynamic data were also similar in both groups. On multivariate analysis, group I patients were only independently associated with more calcified mitral valves and larger left atria. PMV success (area gain > or = 50% without complications) was similar (88 vs 86%) in both groups, but mitral valve area gain was smaller (0.8 +/- 0.3 vs 1.0 +/- 0.3 cm2, p < 0.05) in group I. After PMV an increase in the severity of MR > or = 2 grades (17 vs 6%, p < 0.05) occurred more frequently in group II patients.(ABSTRACT TRUNCATED AT 250 WORDS)