Specific Lesion Characteristics Research Articles

Abstract 12865: Predictors of “Visual-Functional Mismatch” in Contemporary Practice -The Lesion Characteristics Associating With Mismatch Between Angiographic Stenosis and Fractional Flow Reserve

Background: The benefit of fractional flow reserve (FFR) guided percutaneous coronary intervention (PCI) in patients with coronary artery disease compared with angio-guided PCI has shown recently. However, the argument for mismatch (angiographic diameter stenosis ≧ 50% and FFR > 0.80) or reverse-mismatch (angiographic diameter stenosis < 50%, FFR ≦ 0.80), so called, “visual-functional mismatch”, is remains to be solved in contemporary practice. In the present study, we examined the association of the lesion characteristics and “visual-functional mismatch”. Method and Results: We analyzed 140 consecutive patients (157 lesions) undergoing coronary angiography and FFR examination. The mean age of study population was 68.7 years old, 54.3% of them had diabetes, 87.9% of them had hypertension and 77.1% of them had dyslipidemia. In terms of lesion characteristics, ratio of LAD lesion was 58.6%, tandem or diffuse lesion was 48.4%, mean percentage of diameter stenosis was 68.2% and lesion length was 16.3mm. The study population was divided into 4 groups by angiographic stenosis (cut-off: 50%) and FFR (cut-off: 0.80). There were no differences in patients’ background among 4 groups. Mismatches were observed in 28.7% of lesions, whereas, reverse-mismatches were observed in 10.1% of lesions. Lesion characteristics causing “visual-functional mismatch” are shown in Table 1 and ROC curve s of diameter stenosis for functional significance are shown in Figure 1. Conclusion: Specific lesion characteristics are applicable for predicting “visual-functional mismatch”. Angiographic severity seemed to be more reliable in LAD lesions, tandem/diffuse lesions or proximal lesions. FFR measurement should be considered for angiographic 50% stenosis in LAD to perform appropriate PCI, whereas, FFR measurement should be considered for angiographic 75% stenosis in non-LAD to avoid unnecessary PCI.

Association of elevated fasting glucose with lower patency and increased major adverse limb events among patients with diabetes undergoing infrapopliteal balloon angioplasty.

Diabetes mellitus (DM) is a significant risk factor for loss of patency after endovascular intervention, but the contribution of glycemic control to infrapopliteal artery patency among patients with DM is unknown. All percutaneous infrapopliteal interventions among patients with DM from 2006 to 2013 were reviewed and pre-procedure fasting blood glucose (FBG) was recorded. The primary endpoint was primary patency at 1 year as determined by duplex ultrasound. A total of 309 infrapopliteal lesions in 149 patients with DM were treated with balloon angioplasty during the study period. The median FBG was 144 mg/dL. At 1 year, the rate of primary patency was 16% for patients with FBG above the median, compared to 46% for patients with FBG below the median (hazard ratio (HR) 1.82 for FBG ≥144, p=0.005). Amputation rates at 1 year trended higher among patients with high versus low FBG (24% vs 15%, p=0.1). One year major adverse limb event rates were also higher for patients with high versus low FBG (35% vs 23%, p=0.05). Although patients with high FBG were more likely to have insulin-requiring DM (73% vs 50%, p=0.003) the association of high FBG with loss of primary patency remained significant even after adjusting for insulin use as well as other lesion-specific characteristics (adjusted HR 1.8, 95% CI 1.2-2.8). In conclusion, high fasting blood glucose at the time of infrapopliteal balloon angioplasty is associated with significantly decreased primary patency and may also be a risk factor for major adverse limb events among patients with a threatened limb.

Pulsed dye laser-resistant port-wine stains: mechanisms of resistance and implications for treatment

Port-wine stains (PWS) are among the most common congenital vascular malformations. Unlike capillary haemangiomas, these lesions do not involute spontaneously but rather become progressively more disfiguring as the patient ages. While benign in nature, the cosmetic deformity and attendant psychological and emotional distress prompt the majority of those afflicted to seek treatment. The pulsed dye laser (PDL) has long been considered the treatment of choice for these vascular lesions; however, very few patients achieve total clearance with PDL therapy and a significant number of lesions fail to respond at all. In order to address these recalcitrant cases, the mechanisms that contribute to treatment resistance must be understood and novel laser and light therapies must be employed. This review will address what is currently known about lesion-specific characteristics of PDL-resistant PWS as well as discuss current and future treatment options.

Quantitative Measures Confirm the Inverse Relationship between Lesion Spiculation and Detection of Breast Masses

To identify specific mammographic appearances that reduce the mammographic detection of breast cancer. This study received institutional board review approval and all readers gave informed consent. A set of 60 mammograms each consisting of craniocaudal and mediolateral oblique projections were presented to 129 mammogram Breastscreen readers. The images consisted of 20 positive cases with single and multicentric masses in 16 and 4 cases, respectively (resulting in a total of 24 cancers), and readers were asked to identify and locate the lesions. Each lesion was then ranked according to a detectability rating (ie, the number of observers who correctly located the lesion divided by the total number of observers), and this was correlated with breast density, lesion size, and various descriptors of lesion shape and texture. Negative and positive correlations between lesion detection and density (r = -0.64, P = .007) and size (r = 0.65, P = .005), respectively, were demonstrated. In terms of lesion size and shape, there were significant correlations between the probability of detection and area (r = 0.43, P = .04), perimeter (r = 0.66, P = .0004), lesion elongation (r = 0.49, P = .02), and lesion nonspiculation (r = 0.78, P < .0001). The results of this study have identified specific lesion characteristics associated with shape that may contribute to reduced cancer detection. Mammographic sensitivity may be adversely affected without appropriate attention to spiculation.

A 6-Year Experience Treating Vascular Malformations With Foam Sclerotherapy

In this study, the authors present an analysis of the outcomes of 105 low-flow vascular malformation patients treated over a 6-year period and report specific lesion characteristics that correlate with those vascular malformations that will benefit from sodium tetradecyl sulfate foam sclerotherapy (STS FS) versus surgical resection as well as morphological characteristics of vascular malformations that are associated with a poor response to FS treatment. Improvement in symptoms was documented in 92.9% of patients treated with STS FS. There were no complications. Low-flow vascular malformations that were morphologically characterized by microcystic, septated vessels did not respond to FS, and these vascular malformations are best treated with surgical resection. Primary surgical resection is also the treatment of choice for localized, microcystic, and superficial low-flow vascular malformations. Symptomatic, diffuse, extensive, macrocystic malformations that involve multiple tissue planes and vital structures are best treated with FS.

Missed lesions at CT colonography: lessons learned

Misinterpretation at CT colonography (CTC) can result in either a colorectal lesion being missed (false-negative) or a false-positive diagnosis. This review will largely focus on potential missed lesions-and ways to avoid such misses. The general causes of false-negative interpretation at CTC can be broadly characterized and grouped into discrete categories related to suboptimal study technique, specific lesion characteristics, anatomic location, and imaging artifacts. Overlapping causes further increase the likelihood of missing a clinically relevant lesion. In the end, if the technical factors of bowel preparation, colonic distention, and robust CTC software are adequately addressed on a consistent basis, and the reader is aware of all the potential pitfalls at CTC, important lesions will seldom be missed.

Distinct Roles of the Extrinsic and the Intrinsic Coagulation Pathways In Different Murine Thrombosis Models,

Abstract 3278In vivo vascular lesion models are used to elucidate the pathophysiological mechanisms of thrombosis. We found that the intrinsic and extrinsic coagulation pathways exhibit a distinct relative contribution to arterial occlusion initiated by a FeCl3- or nitrogen dye pulse laser (NDPL)-induced injury evaluated comparatively in the carotid artery (CA), the femoral artery (FA) or the femoral vein (FV). Methods. C57Bl/6J (BL6), IL4Rα/GPIbα-tg (IL4) and VWF−/− mice between 8 and 12 weeks of age were anesthetized with 2% isofluorane, and the right jugular vein was cannulated for IV delivery of fluids. Injury in the exposed left CA was induced by applying a 0.7 ml drop of 7 or 8 % FeCl3 for 3 minutes; variations of blood flow in the injured artery were then monitored with a miniaturized ultrasound flow probe for an additional 30 min. In all experiments, FeCl3 concentrations refer to the hexahydrate form of the salt. The time to first occlusion (flow rate <0.1 ml/min) and the normalized area under the flow rate curve, defined as the Flow Index (FI), were used as endpoints for statistical analysis. In the FA and FV, respectively, vascular injury by FeCl3 was induced by applying a 9% drop for 2.5 minutes or 4% drop for 1 minute; then, platelet and fibrin deposition in forming thrombi were visualized by epifluorescence microscopy of injected green calcein-labeled platelets and AlexaFluor 546-labelled anti-fibrin antibody. The NDPL injury was induced in both FV and FA with two series of 30 s laser light pulses, the second upstream of and 30 s after the first. Images selected at regular time intervals from a 20 min real-time video recording were used for measuring the integrated density of formed thrombi with the ImageJ software. Results. In the CA, 8% FeCl3 reliably caused a stable occlusion that was completely abolished by lepirudin, a thrombin inhibitor, at a calculated 42 μM concentration in blood. Also, IL4 mice, lacking a functional extracellular GPIbα domain, and VWF−/− mice failed to develop a normal thrombus. In C57Bl/6J mice, injection of the anti-mouse factor XI (mFXI) monoclonal antibody (mAB) 14E11 inhibited thrombus formation in a dose dependent manner, and completely when injected at a dose of 0.5 μg/g. In contrast, the anti-mouse tissue factor (mTF) mAB 21E10 had no effect when injected at 25 μg/g; the latter amount of anti-mTF mAB was variably inhibitory only when a presumably milder lesion was induced by a reduced 7% FeCl3 concentration. Of note, however, even at the lower dosage of 9 μg/g the anti-mTF mAB completely prevented CA occlusion when co-injected with an individually non-effective dose (0.065 μg/g) of anti-mFXI mAB. Essentially the same results, albeit obtained with a different methodology, were observed by evaluating thrombus formation in the FA and FV after FeCl3-induced injury. Findings were remarkably different in the NDPL model of FA and FV thrombosis. In this case, platelet aggregate formation was transient and almost completely reversed by 20 minute post-injury, while fibrin deposition at the site of injury increased progressively in time. Fibrin deposition was essentially absent in the IL4 mouse but, contrary to what we observed in the same vascular beds after FeCl3 injury, it was only partially inhibited by injecting the anti-mFXI mAB at dosage as high as 1 μg/g. Moreover, and again in contrast with the results after FeCl3 injury, the anti-mTF mAB injected at 25 μg/g by itself significantly inhibited fibrin deposition. Conclusions. Our findings indicate that distinct thrombogenic vascular lesions elicit a varied response by the extrinsic and intrinsic coagulation pathways, as reflected by the different effects of inhibiting initiating events mediated by TF or FXI activation by FXIIa (the reaction blocked by mAB 14E11), respectively. Moreover, and again in a lesion-specific manner, the two coagulation pathways exhibit a variably relevant synergistic function in leading to thrombin generation as evidenced by fibrin deposition. These results, and the underlying mechanisms presently under investigation, suggest that the thrombogenic potential of different pathological lesions in human vascular disease is also likely varied and may be influenced by lesion-specific characteristics. Consequently, more direct mechanistic evidence must be generated to establish how a given animal thrombosis model may reflect the pathogenesis of acute vascular occlusion in human disease. Disclosures:Gruber:Aronora, LLC: Consultancy, Equity Ownership.

CT-guided liver biopsy: correlation of procedure time and radiation dose with patient size, weight, and lesion volume and depth

Purpose The purpose of this study was to retrospectively evaluate the effect of various factors, including overall patient size, weight, and individual lesion characteristics, on the radiation dose and procedure time required to successfully perform computed tomography (CT)-guided liver lesion biopsies. Materials and Methods This Institutional-Review-Board-approved study included 209 patients (average age, 59 years; range, 19–86 years; 105 males, 104 females) who underwent CT-guided liver lesion biopsy on a four-slice multidetector row CT scanner (LightSpeed Qx/i; GE Healthcare, Milwaukee, WI). Medical records and images were retrospectively reviewed to obtain the following data: (a) patient weight, (b) patient size, (c) lesion volume, (d) lesion depth, (e) CT dose index (CTDI) and effective radiation dose, and (f) procedure time. Statistical analysis was performed with multiple linear regression to assess the effect of various parameters on radiation dose and procedure time. Results CTDI was significantly correlated with patient weight ( P<.01), size ( P=.03), and lesion volume ( P<.01). The total effective radiation dose was significantly correlated with patient size ( P<.01) and lesion depth ( P<.01). Total procedure time was significantly correlated with lesion volume ( P<.01) and depth ( P<.01). There was a positive correlation between procedure time and effective radiation dose ( r 2=.57). Conclusion In the current study, CT-guided liver lesion biopsy patient radiation dose was associated with both overall patient-specific features (weight and size) and specific lesion characteristics; however, the procedure duration was determined by lesion characteristics (lesion volume and depth) alone.

Factors Determining the Sensitivity of Intraoperative Ultrasonography in Detecting Colorectal Liver Metastases in the Modern Era

With improved preoperative cross-sectional imaging, the added clinical value of intraoperative ultrasonography (IOUS) in the detection of colorectal liver metastases (CRLM) is unclear. Specifically, the ability of IOUS to detect additional liver metastases during surgery and its relationship between clinical and lesion specific ultrasonographic characteristics remains ill-defined. The purpose of the current study was to determine the association of clinical parameters and tumor echogenicity with the ability of IOUS to detect occult CRLM. A total of 213 patients undergoing surgical exploration and IOUS for CRLM between 1998 and 2009 were included in the study. All patients underwent preoperative multidetector computed tomography (CT) imaging and lesion detection was compared with those identified by IOUS. In addition, early (<6months) intrahepatic recurrence was used as a surrogate for residual disease (e.g., metastases that were undetected on initial IOUS). The influence of various characteristics on the rate in which additional metastases were detected and the rate of early intrahepatic recurrence was examined. Overall, IOUS detected additional liver metastases in 10% of patients (n=22). Detection of additional metastases was significantly higher in patients with multiple (≥4) tumors (P<0.001) and hypoechoic tumors (P=0.007). Of 153 patients undergoing resection only, 17 (11%) had an early intrahepatic recurrence. This was more common in patients with isoechoic metastases during IOUS (P=0.03). Even with the use of modern cross-sectional preoperative imaging, IOUS detects additional liver metastases in 10% of patients. In addition, the sensitivity of IOUS for detecting occult CRLM is highly dependent on the number and echogenicity of detected tumors.

Abstract 2001: Clinical and Angiographic Predictors of 30-Day and One-Year Ischemic Cardiac Events in Patients with Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention: An ACUITY Substudy

Background: Clinical predictors of short and long-term ischemic outcomes following PCI in acute coronary syndromes (ACS) have been well studied. However, the angiographic predictors of adverse events have not been defined. Methods: The ACUITY trial randomized 13,819 pts with moderate and high risk ACS to unfractionated heparin or enoxaparin + GP IIb/Iii inhibitors (GPI), versus bivalirudin + GPI, vs. bivalirudin alone. The angiographic substudy of ACUITY included the first 7000 consecutive randomized US patients, of which 3664 underwent PCI. All angiograms were reviewed by an independent core laboratory for complete 3 vessel assessment of extent and CAD burden (total mm length of lesions with &gt;30%DS), as well as baseline and final lesion and flow characteristics. Clinical and angiographic predictors of composite ischemia (death, non-fatal MI, or ischemic target vessel revascularization) at 30 days and 1 year were identified by univariate and multivariable analysis using logistic regression analysis. Results: Coronary stents were used in 3429 (93.6%) pts, (84.4% DES). Composite ischemia occurred in 366 pts (10.0%) at 30 days and in 735 pts (21.0%) at one year. The independent predictors of 30 day and 1 year composite ischemic events by multivariable analysis are shown in the table . Conclusions: Beyond the clinical predictors of renal insufficiency and diabetes, CAD burden assessed by the number of diseased coronary vessels and the burden of CAD are independent predictor of 30 day and 1 year ischemic events in patients with ACS undergoing PCI. Baseline lesion specific characteristics including eccentric and calcified lesions, as well as angiographic PCI complications resulting in sustained no reflow, abrupt closure or thrombus were also independently predictive of adverse events. Table 7: Multivariate Predictors of Composite Ischemia

Pineocytoma Mimicking a Pineal Cyst on Imaging: True Diagnostic Dilemma or a Case of Incomplete Imaging?: Fig 1.

Pineocytomas have been described as well-circumscribed, homogeneously enhancing masses. However, there is considerable variability in this appearance, and certain pineocytomas may have a predominantly cystic appearance on imaging. This has led some to suggest that differentiation between pineocytomas and pineal cysts may not be possible. We have attempted to determine if cystic pineocytomas could be found in a series of these tumors evaluated by CT and MR imaging. We searched the radiology literature as well as the medical records from our own institution for pathologically proved pineocytomas with available preoperative imaging or imaging reports, with specific focus on whether postcontrast MR imaging was included. In cases in which images were available, they were evaluated by a Certificate of Added Qualification (CAQ)-certified neuroradiologist and a radiology resident, who attempted to determine if the pineocytomas had any MR imaging characteristics of typical pineal cysts. To be considered a typical pineal cyst, an area of signal-intensity abnormality must be centered on the pineal recess, demonstrating internal homogeneity on T2-weighted imaging, following CSF signal intensity on T1- and T2-weighted images, without any marginal lobularity or nodular contrast enhancement and a wall thickness of <2 mm. In cases in which imaging was not available, radiology reports and/or descriptions provided in the radiology literature were reviewed by a CAQ-certified neuroradiologist. For any lesion described as cystic, we again attempted to elucidate the exact extent of imaging that was performed, note specific lesion characteristics, and determine if the lesion met the criteria described previously. Finally, for tumors in which image size was provided, the mean value of maximal tumor dimension, SD, median, and range were calculated. Forty-four pathologically proved cases of pineocytomas from the radiology literature, as well as 8 pathologically proved cases of pineocytomas from our institution with available imaging studies and/or reports, were reviewed. Of these, 23 were solid masses, and 7 were partially solid and cystic, whereas 14 tumors could not be completely characterized due to incomplete imaging evaluation. Eight were primarily cystic; however, none of these could be confidently characterized as meeting the criteria for a typical cyst. In our analysis, no truly cystic pineocytomas were identified.

Evolution of Anticoagulant and Antiplatelet Therapy: Benefits and Risks of Contemporary Pharmacologic Agents and Their Implications for Myonecrosis and Bleeding in Percutaneous Coronary Intervention

Periprocedural myonecrosis, as evidenced by elevated creatine kinase-myocardial bound (CK-MB) levels, occurs in up to 25% of patients undergoing percutaneous coronary intervention (PCI) and has been linked with an increased risk of adverse short- and long-term clinical outcomes. Such myonecrosis arises from three main pathophysiological mechanisms: procedure-related complications, lesion-specific characteristics (e.g., large thrombus burden, plaque volume), and patient-specific characteristics (e.g., genetic predisposition, arterial inflammation). Periprocedural myonecrosis has not been definitively identified as the cause of postprocedural ischemic events, although agents that reduce or prevent thrombosis--including aspirin, thienopyridines, heparin, low-molecular-weight heparins, glycoprotein IIb/IIIa inhibitors, and direct thrombin inhibitors--have been shown to reduce the incidence of ischemic outcomes in this population, as have agents that reduce inflammation (aspirin, statins). At the same time, antithrombotic agents are known to increase the risk of bleeding and the use of transfusions, which have likewise been associated with worse outcomes in these patients. Thus, optimal management of patients undergoing PCI represents a balance between minimizing the risk of ischemic outcomes and simultaneously minimizing the risk of major bleeding. It may be that patients who have only minor, untreated postprocedural elevations in CK-MB level (with no clinical or angiographic signs of ischemia) might have a better prognosis than patients who have normal CK-MB levels but who suffer major bleeding complications.

Dual Antiplatelet Therapy for Coronary Stenting

It was an important and indeed remarkable observation when several trials reported the consistent finding that dual antiplatelet therapy with aspirin and a thienopyridine was superior to aspirin and oral anticoagulation for prevention of major adverse cardiac events after deployment of a stent in a coronary artery.1 A major benefit of dual antiplatelet therapy was a lower rate of stent thrombosis. The incidence of coronary stent thrombosis in the modern era is reported to be approximately 1%, with an increased likelihood of occurrence in high-risk patient or lesion subsets. Although this rate may seem relatively low, stent thrombosis is associated with major myocardial infarction (MI) in 60% to 70% of cases, resulting in an early mortality rate of 20% to 25%. With increased use of percutaneous coronary intervention (PCI) as a revascularization strategy and implantation of stents in coronary arteries with a small diameter, it is anticipated that the number of patients at risk for stent thrombosis may increase. It therefore continues to be important to construct pharmacological regimens that minimize its occurrence. Several risk factors for stent thrombosis have been identified, including patient- and/or lesion-specific characteristics, procedure-related factors, and inherent stent thrombogenicity.2 These risk factors, in turn, contribute to a state of enhanced platelet reactivity and thrombus formation, which promotes abrupt vessel closure. See p 1153 Although initial studies highlighting the benefits of dual antiplatelet therapy used aspirin and ticlopidine, clopidogrel is the thienopyridine of choice today because it is associated with a lower rate of intolerable side effects. It is noteworthy that clopidogrel as part of the dual antiplatelet regimen to support PCI has not undergone the type of extensive evaluation demanded of ACE inhibitors, angiotensin receptor blockers, or such devices as implantable cardioverter-defibrillators before they were recommended in practice guidelines for management of patients with …

Thirty month outcome from early childhood head injury: a prospective analysis of neurobehavioural recovery

Traumatic brain injury (TBI) is a common cause of acquired disability during childhood. While much is now known about outcome following TBI in the school-aged population, recovery in infants and young children is less well documented. The aim of this study was to examine neurobehavioural function following TBI during early childhood, to plot recovery over the 30 months post-injury and to identify predictors of outcome. The study compared three groups of children, sustaining injuries of different severity (mild = 14, moderate = 46, severe = 24), aged 2.0-6.11 years at injury, with a healthy control group (n = 33). The groups were similar with respect to pre-injury adaptive and behavioural function, psychosocial characteristics, age and gender. Using a prospective, longitudinal design, intellectual, language and memory functions were investigated acutely post-injury and again at 12 and 30 months post-injury. Results suggested a strong association between injury severity across all neurobehavioural domains. Further, 30 month outcome was predicted by multiple factors including injury severity, socio-economic status, pre-injury adaptive abilities and age, with pre-injury child behaviour and specific lesion characteristics playing surprisingly little role. In conclusion, children with more severe injuries, lower pre-injury adaptive abilities and lower socio-economic status are at greatest risk of long-term neurobehavioural impairment, even several years post-injury.

Brachytherapy for in-stent restenosis in general interventional practice: A single institution's experience using four radiation devices

Background The effectiveness of brachytherapy for the treatment of in-stent restenosis (ISR) has been established in a number of large randomized controlled trials. Efficacy of this therapy in general population is less well established. Methods and materials We report our experience of 207 patients, 236 coronary lesions, treated with brachytherapy between November 2000 and November 2002. All commercially available brachytherapy devices, as well as one investigational device, were utilized. This cohort was followed over 9 months and clinical outcomes were obtained with subsequent analysis of patient and lesion-specific characteristics. Results Average treatment age was 62.5 years; 73% were male and the most frequent presentation was unstable angina (74%). All patients had successful delivery of radiation, with no in-hospital deaths. Novoste BetaCath device was used for 163 (65%) lesions, Cordis Checkmate for 56 (24%) lesions, Interventional Therapies device in 13 (8%) lesions, and Guidant Galileo in 4 lesions (3%). At a mean follow-up of 9.1 months, 78.7% were free of major adverse cardiac event (MACE). Twenty-one patients required repeat PTCA (10.1%), 19 had CABG (9.2%), 3 had MI (1.4%), and there was 1 death (0.5%). Unadjusted MACE rates for each device were 21% for Novoste, 28% for Checkmate, 8% for Interventional Therapies, and 50% for Galileo. Lesion length, minimal lumen diameter, renal failure, diabetes, and smoking did not predict treatment failure; only age was inversely correlated with MACE ( P=.002). Conclusion When applied across a spectrum of patients, lesions, and devices, brachytherapy retains its effectiveness with outcomes similar to those reported in randomized clinical trials.

Percutaneous transluminal cerebral angioplasty: serial angiographic follow-up after successful dilatation

The purposes of this study were to determine the optimal time for initial follow-up angiography, the restenosis rate after successful intracranial percutaneous transluminal cerebral angioplasty (PTCBA), and finally to identify lesion-specific characteristics for predicting successful angioplasty. Thirty-five patients underwent PTCBA with follow-up angiography 3 and 12 months later. Although 27 lesions were adequately dilated, permanent complications occurred in 3 patients. The restenosis rate at 3 months was 29.6 %; patients without restenosis at 3 months remained free from vessel narrowing at 12 months. Restenosis occurred on severe, eccentric lesions, total occlusions or extremely angulated lesions. There was a strong correlation between sufficient dilatation and lower restenosis rate, and concentric and short lesions (type A). We conclude that the optimal time for initial angiographic follow-up is 3 months after PTCBA. PTCBA is most suitable for type A lesions with higher success, lower morbidity and lower restenosis rates.

Adjunctive intracoronary infusion of antithrombin III during percutaneous transluminal coronary angioplasty. Results of a prospective, randomized trial.

Heparin needs the plasma protein antithrombin III to function as an inhibitor of thrombin, and local antithrombin III deficiency might therefore limit the antithrombotic effectiveness of heparin during percutaneous transluminal coronary angioplasty. In the present double-blind study, 615 consecutive patients undergoing percutaneous transluminal coronary angioplasty (PTCA), of a total of 713 stenoses, were prospectively randomized to receive a bolus injection of 15,000 U heparin followed by a continuous intracoronary infusion via the guiding catheter of either 250 U heparin per minute or 250 U heparin plus 25 U antithrombin III per minute during the procedure. Four clinical variables, 19 lesion-specific characteristics, and 16 procedure-related variables were evaluated. Procedural success was assessed by quantitative angiography; procedure-related ischemic complications were analyzed during in-hospital follow-up. Procedural success rates (< 50% final diameter stenosis and no major ischemic complication) were similar, with 85% in the heparin group (n = 324 patients) and 83% in the heparin+antithrombin III group (n = 291 patients). Percent diameter stenosis after PTCA was 39 +/- 18% in the heparin group and 40 +/- 20% in the heparin+antithrombin III group (NS). There were no differences between the two groups with respect to PTCA-related acute vessel occlusion, angiographic evidence of intracoronary thrombus formation, post-procedure creatine kinase increase, Q-wave myocardial infarction, or emergency coronary artery bypass surgery. High-risk subgroup analysis revealed no beneficial effect of adjunctive intracoronary antithrombin III in any of the analyzed subgroups. In addition, although risk stratification according to the criteria of the American College of Cardiology/American Heart Association Task Force classification proved to be very useful for the entire study population, no beneficial effect of intracoronary antithrombin III infusion was observed in any of the different risk groups. Compared with heparin alone, adjunctive intracoronary antithrombin III therapy does not appear to have any beneficial effect on procedural outcome as well as type and frequency of acute complications during PTCA even in subgroups of patients with a high risk for thrombotic complications. Thus, a local deficiency of antithrombin III does not play a major role for the failure of heparin to abolish thrombotic complications during PTCA.

RADIOLUCENCIES WITH DISTINCT BORDERS

The differential diagnosis of circumscribed radiolucencies or those with distinct borders requires careful evaluation of lesion-specific characteristics. This evaluation is necessary because of the variable prognosis and possible aggressiveness of lesions that may fall into this category, which also contains many benign conditions. This section reviews the clinical features, radiographic appearance, histopathologic findings, and treatment recommendations for a selected group of lesions.

Indications for directional coronary atherectoy:1993

New coronary devices are being developed in attempts to solve the limitations of balloon angoplasty. Directional coronary atherectomy was the first of these devices to gain Food and Drug, Administration approval. Theoretically, directional atherectomy improves coronary stenoses by an entirely different mechanism than balloon angioplasty, removing atherosclerotic plaque and leaving a smooth surface with less elastic recoil. Nonrandomized experience has shown that directional atherectomy is most useful in proximal to mid-segment, noncalcified, large (>2.5 mm) coronary arterial segments, yielding minimal residual stenosis and larger lumen diameters than are generally achieved with angoplasty. Experience suggests that directional atherectomy is most useful in ostial coronary lesions, bifurcation stenoses, proximal left anterior descending lesions, discrete saphenous vein graft stenoses, complex or thrombus-containing lesions, highly eccentric lesions, and lesions failing PTCA secondary to elastic recoil, recurrent thrombosis, or limited dissection. Dissection and out-of-catheterization-laboratory acute closure are infrequent and appear to be improved over balloon angioplasty. However, intimal hyperplasia leading to restenosis is not solved by directional atherectomy. Randomized studies such as the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT) will help to clarify further the overall utility of directional atherectomy compared with balloon angoplasty in the future, but due to the limited power of subgroup analyses, CAVEAT may not have fully defined all the specific lesion characteristics that may be improved by atherectomy over PTCA. Review of the data presented may help the clinician identify specific areas In which atherectomy appears to offer an advantage over angioplasty although definitive answers await specifically targeted randomized trials.