bluuebunny/crossref_metadata_2025 huggingface dataset:
Coronary Laser Thermal Angioplasty in the Swine: Reduced Complications with Shorter Laser Delivery Time
Authors: ALEXOPOULOS DIMITRIOS , SANBORN TIMOTHY A. , BADIMON JUAN JOSE , BADIMON UNA , DISCHE RENATE , FUSTER VALENTIN
Published: June 2007

Although laser thermal angioplasty (LTA) with a laser heated metal probe has been tolerated in diseased human coronary arteries, definition of a safety threshold is lacking. Determination of safer operation parameters for coronary LTA using a new “over the wire” 1.3‐mm laser probe catheter was attempted in seven normal pigs in which platelets were labeled with indium‐III. Argon laser power of 10 watts was used for 1, 2, 3, and 5 seconds. Macroscopic findings, platelet deposition and histologic changes were compared between the laser treated coronary segments and controls, the nonheated laser probe, and the wire alone segments. After 1‐second LTA, there was no vessel perforation or occlusive thrombi and only infrequent nonocclusive thrombi; platelet deposition was minimal; and histologic alterations rare and superficial. These findings were comparable to controls, the nonheated laser probe, and the wire alone segments. In contrast, vessels treated for 2, 3, and 5 seconds had more frequent perforation, and occlusive and nonocclusive thrombi that was accompanied by platelet deposition significantly greater than vessels treated with LTA for I second. A deep histologic injury was present in most of these segments. Additionally, the safety of laser delivery of I second repeated for five times was tested in two additional pigs. On macroscopic and histologic analysis the incidence of vessel perforation, occlusive and nonocclusive thrombi appeared slightly less when compared to the 2‐, 3‐, and 5‐second LTA groups, and more than the 1‐second LTA group. Platelet deposition was lower than the 2‐, 3‐, and 5‐second LTA groups, and higher than the 1‐second pulse group. Thus, 1‐second pulses are the threshold for safe application of LTA in normal swine coronary arteries. LTA for longer periods of energy delivery is accompanied by significant platelet deposition and high rates of thrombi formation focclusive and nonocclusive) and vessel wall perforation. Repetitive short 1‐second periods of laser energy delivery do produce an accumulative injury but to a less extent than single pulses. This mode of laser energy delivery could possibly improve the safety for human LTA.
Complications of Intraaortic Balloon Counterpulsation Insertion in Patients Receiving Thrombolytic Therapy for Acute Myocardial Infarction
Authors: SILVERMAN ALAN J. , WILLIAMS ALICIA M. , WETMORE ROBERT W. , PHARM D. , STOMEL ROBERT J.
Published: June 2007

This study retrospectively examines 38 patients who presented with acute myocardial infarction requiring intraaortic balloon pump counterpulsation. Two groups of patients were identified. Group I consisted of patients with acute myocardial infarction treated with intraaortic balloon pump without thrombolytic therapy. Group II consisted of patients treated with intraaortic balloon pump after receiving intravenous thrombolytic therapy. These groups were compared and contrasted with regard to previously identified complications associated with intraaortic balloon pump counterpulsation including loss of limb and mortality. The need for surgery, embolectomy, and drainage of hematoma were also evaluated. The need for surgery in group II (11%) and in both groups combined (7%) is lower than is generally reported in literature (range 11.6% to 34%). In addition, no patients experienced a loss of limb and no patients in the study had severe life‐threatening iatrogenic morbidity or mortality. While mortality was not an end point in this study, it was noted that there was an increased survival rate in group II patients with 61% surviving until the time of hospital discharge. Also, eight out of 14 patients in group II who underwent intraaortic balloon pump counterpulsation for cardiogenic shock survived until the time of discharge. This represents a 57% survival rate for patients presenting with cardiogenic shock. We conclude that intraaortic balloon pumps can be inserted safely following thrombolytic therapy in a community hospital.
From Peripheral to Coronary Dynamic Angioplasty: Analysis of Resulting Particles
Authors: GEHANI ABDURRAZZAK ABDULKADER , BALL STEPHEN GEOFFRY , STOODLEY KEITH , ASHLEY SIMON , BROOK STEPHEN GERALD , REES MICHAEL RALPH
Published: June 2007

The factors that could reduce the size of particles generated by peripheral (8 Fr) and coronary (5 Fr) Kensey catheters (KC) in calcified and noncalcified atheroma were investigated. Fresh endarterectomy specimens (72 calcified, 72 noncalcified) were inserted in a flow circuit and randomized to undergo simulated dynamic angioplasty using 5 Fr or 8 Fr KC at a range of predetermined cam speeds (20,000–80,000 rpm) and flow rates (18–60 mL/min). Atherectomy as measured by weight loss from the specimen was greater in noncalcified lesions, 21.4 ± 4.5 mg and 14.9 ± 3.8 mg, respectively (P < 0.001). In calcified atheroma, the atherectomy was asymmetrical in 38 out of 72 specimens but in only 12 of 72 noncalcified lesions (P < 0.01). Overall, 65%± 3.9% of collected particles were smaller than 5 μm and 86.8%± 9.1% were smaller than 35 μm. In the remaining 13.2%± 8.9% of particles larger than 35 μm, significant differences were detected between the maximum particle size in each group. Larger particles were generated from calcified atheroma. In noncalcified lesions, increasing cam speed reduced maximum particle size from 890 to 170 μm (P < 0.001). Although a higher flow rate and the use of 5 Fr catheter have also significantly reduced the particle size, their effect was less than that exerted by cam speed. In calcified atheroma, cam speed was the only factor observed to influence the maximal particle size, reducing it from 1,260 to 381 μm (P < 0.001). In conclusion, although the majority of particles resulting from the use of KC were small, a proportion of large particles was also detected. Their size could be significantly reduced by careful adjustment of the operating parameters. These results are important for future application of KC in coronary dynamic angioplasty. However, the impact of reducing particle size on the risk of embolism in vivo requires further study.
Transluminal Balloon Dilatation For Discrete Subaortic Stenosis in Adults and Children: Early and Intermediate Results
Authors: SHARMA SATYAVAN , BHAGWAT A. R. , LOYA Y. S.
Published: June 2007

Seven patients (four adults, three children) with discrete subaortic membranous stenosis underwent balloon dilatation procedures using a single or double balloon technique with reduction in systolic gradient across the membrane from 100.42 ± 19.23 to 29.14 ± 72.54 mmHg (P < 0.001). Echocar‐diography demonstrated thin membranes in all the patients and postprocedure torn fragments could be visualized. The excellent hemodynamic benefits are sustained during 4–24 months follow‐up. The results indicate that transluminal balloon dilatation can be a safe and effective treatment for thin subaortic membrane.
Transcatheter Radiofrequency Ablation in the Canine Right Atrium
Authors: LEE MICHAEL A. , HUANG SHOEI K. STEPHEN , GRAHAM ANNA R. , GORMAN GRACE , BHARATI SAROJA , LEV MAURICE
Published: June 2007

The feasibility of using radiofrequency energy for potential ablation of atrial tachycardia foci was assessed by performing transcatheter ablation in the right atrium in 11 closed‐chest dogs. Single‐pulsed radiofrequency (750 kHz) energy was delivered to the right atrium (29–254 J) between the tip electrode of a standard 6 Fr quadripolar catheter and a chest patch electrode. There were no significant arrhythmias or complications noted. Dogs were sacrificed 0–29 days after ablation to assess acute and subacute effects of this technique. Of 47 attempted ablations, 36 well‐delineated coagulative lesions were identified. The lesions had a mean dimension of 5.2 ± 0.57 mm (± SE) in length, 3.9 ± 0.27 mm in width, and 2.6 ± 0.17 mm in depth. Transmural necrosis was noted in 6 of 36 lesions (17%) without perforation. A thin layer of mural thrombus was found in 5 of 36 lesions (14%). Thus, this technique appears to be feasible and relatively safe for right atrial ablations in a short‐term follow‐up period. The potential application of this method to ablate right atrial tachycardia foci needs to be further investigated.
A New Bioabsorbable Intravascular Stent: In Vitro Assessment of Hemodynamic and Morphometric Characteristics
Authors: BIER JONATHAN D. , ZALESKY PAUL , LI SHU‐TUNG , SASKEN HARVEY , WILLIAMS DAVID O.
Published: June 2007

Currently available intracoronary stents are permanent and their placement may be complicated by thrombosis and restenosis. We have developed a new bioresorbable stent constructed of type I collagen. This stent has a compliant tubular structure that is self expanding and carries a net negative surface charge to increase hemocompatibility. In vitro histologic and morphometric examination was performed by deploying the scent in six pressure fixed explanted porcine arteries. Morphometry revealed a close relationship between the stem external diameter (2.9 ± 0.4 mm) and the arterial lumen diameter (3.0 ± 0.4 mm). A relative reduction in arterial lumen diameter secondary to stem placement of 17% to 26% was observed. Folding of the stent wall was noted in those preparations where the stent external diameter was larger than the arterial lumen diameter. Polyvinyl chloride (PVC) tubing was used as a mock arterial segment for flow studies. Flow at baseline and following stent placement was determined at perfusion pressures of 10, 50, and 80 mmHg. A modest reduction in flow following stem placement of between 2% and 6% was observed. Thus, type I collagen may be used to construct a self expanding tubular stent. Morphometric and hemodynamic evaluation reveals a modest impact on arterial lumen dimensions and flow
Prolonged Thrombolysis Followed by Double Balloon Angioplasty for an Abdominal Aortic Occlusion
Authors: IYER SRIRAM S. , HALL PATRICK , DORROS GERALD
Published: June 2007

A 69‐year‐old woman was admitted with clinical symptoms of an acute abdominal aortic occlusion. Femoral and distal pulses were absent with lower extremity paralysis and loss of sensation. Digital subtraction angiogram confirmed the infrarenal abdominal aortic occlusion. A selective urokinase infusion was initiated from a left brachial approach and continued in conjunction with heparin therapy for 48 hours. Clinical improvement was noted in 24 hours. By 48 hours there was complete abdominal aorta thrombolysis with angiograms revealing bilateral common iliac stenosis. The percutaneous intervention was completed from a brachial approach utilizing conventional (5 French) balloon angioplasty catheters using a double wire “kissing” balloon technique. Following angioplasty, distal pulses were present; the angiograms confirmed patent vessels with excellent distal flow. (J Interven Cardiol 1991; 5:25–27)
The Use of the Holmium:YAG Laser in Coronary Disease: The Utility of a Unique Lensed Fiber Catheter
Authors: HEUSER RICHARD R.
Published: June 2007

Alternatives to balloon angioplasty, which has a restenosis rate of 25%–68%, are being sought for patients at high risk for restenosis. The mid‐infrared holmium laser may have properties more advantageous for coronary angioplasty than the ultraviolet excimer laser. The Coronary HaloCath (Trimedyne, Inc.) has a diverging lens that allows the beam diameter to approximate the catheter tip diameter, increasing the size of the channel that can be created by laser ablation. This unique ability may make it more efficacious in treating arteriosclerotic disease. This device was used to treat: I) a chronic total occlusion, creating a recanalized diameter larger than the catheter diameter; and 2) an ostial right coronary stenosis, which opened more readily than would have been expected with balloon angioplasty. The Coronary HaloCath may prove useful in difficult‐to‐treat coronary lesions. (J Interven Cardiol 1992; 5:293–300)
“Over The Shoulder” Guidewire Manipulation Through An Angulated Stenosis Adjacent To A Coronary Aneurysm During High Risk Percutaneous Transluminal Angioplasty
Authors: KRUCOFF MITCHELL W. , JACKMAN JOHN D. , CRATER SUZANNE W. , SAWCHAK SHARON T. , CURTIS GLORIA J. , PHILLIPS HARRY R.
Published: June 2007

Angioplasty in the setting of poor left ventricular function may involve coronary anatomy with special challenges to the technique of the operator and the safety of the patient. Spontaneous coronary aneurysms involve a disruption of the tissue of the vessel and the linear geometry of the lumen. This case reports the dilatation of a stenosis traversing a large spontaneous aneurysm in a patient with severe left ventricular dysfunction. Using a novel guidewire technique to traverse the lesion and a perfusion balloon catheter to slowly dilate it, an excellent angiographic and clinical result was achieved. (J Interven Cardiol 1992; 5:232–330)
Percutaneous Coronary Intervention for Diffuse Coronary Artery Disease
Authors: PRIESTLEY KIM A. , BULLER NIGEL P.
Published: June 2007

Patients with diffuse coronary artery disease present a significant management problem. It has been proposed that diffuse coronary disease is unsuitable for balloon angioplasty and surgical treatment is not ideal either. We review the evidence that coronary balloon angioplasty is not a suitable treatment for diffuse coronary disease and examine the role of alternative interventional techniques. New techniques including long angioplasty balloon catheters and atherectomy devices have shown promise. If this is confirmed by prospective randomized trials then coronary angioplasty may yet prove an attractive treatment for diffuse coronary disease.
Ultrasonic Thrombus Ablation: In Vitro Assessment of a Novel Device for Intracoronary Use
Authors: HARTNELL GEORGE G. , SAXTON JANET M. , FRIEDL STEPHAN E. , ABELA GEORGE S. , ROSENSCHEIN URI
Published: June 2007

An ultrasonic thrombolysis device designed for intracoronary use was developed and evaluated in vitro to assess efficacy in achieving clot ablation without deleterious effects, such as heat generation and production of large particles during clot ablation. Studies on 31 samples with a bench‐top version demonstrated that clot ablation was rapid (typically 2 mL in under 2 minutes) and no macroscopic particles were released. The fluid produced did not reclot. Studies with a clinical version of the device that can be passed through a IOFr PTCA guiding catheter confirmed that clot ablation was rapidly achieved. Little particulate material was produced and the maximum temperature achieved did not exceed 52°C. The device functions well in vitro, releasing little particulate material and causing limited local heating. It seems suitable for intracoronary use and will undergo further in vivo testing.
Balloon‐Expandable Stent Treatment of Experimental Coarctation of the Aorta: Early Hemodynamic and Pathological Evaluation
Authors: BEEKMAN ROBERT H. , MULLER DAVID W. M. , REYNOLDS PAUL I. , MOOREHEAD CATHERINE , HEIDELBERGER KATHLEEN , LUPINETTI FLAVIAN M.
Published: June 2007

The present study was intended to evaluate the acute and short‐term hemodynamic, angiographic, and pathological response to balloon‐expandable stent treatment of experimental coarctation of the aorta. A discrete thoracic coarctation was surgically created in six mongrel dogs (two adults, four puppies). Two months postoperatively all six dogs (8.9–30 kg) underwent left heart catheterization and coarctation stenting performed through a femoral artery cutdown. A Palmaz PS‐30 stent was advanced to the coarctation through a 10French sheath, and expanded with an angioplasty balloon chosen to equal the diameter of the proximal aorta (9–12 mm). Stent implantation was successful in each dog. The systolic pressure gradient decreased from 26.3 ± 9.1 mmHg (mean ± SE) to 0.5 ± 0.5 mmHg (P = 0.04), and the coarctation diameter improved from 50 ± 6% to 82 ± 6% of the diameter of the proximal descending aorta (P < 0.01). Follow‐up catheterization 4–7 weeks after stenting documented no stent migration, early restenosis, thrombosis, obstruction of arterial side branches, or aneurysm formation. Pathological evaluation of the explanted segments of stented aorta documented that by 6–7 weeks the stents are covered by a neointima composed of intimal proliferation and fibrosis with an endothelial cell surface. These data suggest that balloon‐expandable stainless steel stents provide excellent acute and short‐term relief of coarctation in this experimental model. Larger and longer‐term studies are needed to better assess the incidence of restenosis or aneurysm formation following stenting of coarctation of the aorta.
Comparison of Catheter Ablation Using Direct Current Energy Versus Radiofrequency: Observations in 147 Patients With Supraventricular Tachyarrhythmias
Authors: TRAPPE HANS‐JOACHIM , KLEIN HELMUT , WENZLAFF PAUL , HUANG JIE , LICHTLEN PAUL R.
Published: June 2007

We studied the follow‐up of 147 patients who underwent catheter ablation because of drug resistant supraventricular tachyarrhythmias. Direct current (DC) ablation was performed in 116 patients, while 31 patients underwent radiofrequency (RF) ablation. In 101 patients (87%) with DC ablation and in 28 patients (90%) with RF ablation, complete atrioventricular (AV) block was achieved initially. Fifteen patients (13%) with DC ablation and three patients (11%) with RF ablation resumed AV conduction. Serious complications occurred in eight patients (7%) with DC ablation and in none of the patients with RF ablation. During the mean follow‐up of 45 ± 24 months, 13 patients died (11%) who underwent DC ablation; during the mean follow‐up of 11 ± 3 months, no patient died who had had RF ablation. Transcatheter ablation using DC or RF is an effective treatment in patients with drug resistant supraventricular arrhythmias, providing a beneficial long‐term outcome including an improved quality of life. Although the risk of complications is low, this procedure should be reserved for patients with supraventricular arrhythmias who do not respond to conventional drug therapy. (J Interven Cardiol 1993; 6:137–147)
An Introduction to Clinical Microeconomic Analysis: Purposes and Analytic Methods
Authors: WEINTRAUB WILLIAM S. , MAULDIN PATRICK D. , BECKER EDMUND R.
Published: June 2007

The recent concern with health care economics has fostered the development of a new discipline that is generally called clinical microeconomics. This is a discipline in which microeconomic methods are used to study the economics of specific medical therapies. It is possible to perform stand alone cost analyses, but more profound insight into the medical decision making process may be accomplished by combining cost studies with measures of outcome. This is most often accomplished with cost‐effectiveness or cost‐utility studies. In costeffectiveness studies there is one measure of outcome, often death. In cost‐utility studies there are multiple measures of outcome, which must be grouped together to give an overall picture of outcome or utility. There are theoretical limitations to the determination of utility that must be accepted to perform this type of analysis. A summary statement of outcome is quality adjusted life years (QALYs), which is utility time socially discounted survival. Discounting is used because people value a year of future life less than a year of present life. Costs are made up of in‐hospital direct, professional, follow‐up direct, and follow‐up indirect costs. Direct costs are for medical services. Indirect costs reflect opportunity costs such as lost time at work. Cost estimates are often based on marginal costs, or the cost for one additional procedure of the same type. Finally an overall statistic may be generated as cost per unit increase in effectiveness, such as dollars per QAL Y. All these measures may be varied by sensitivity analysis to determine the robustness of outcome for medical decision and policy making purposes.
Spontaneous Coronary Arterial Dissection Causing Acute Myocardial Infarction
Authors: CARELL EDGAR S. , TOOLE THERON C. , LACHTERMAN BRUCE , KRISHNASWAMI ASHOK , ANDERSON H. VERNON
Published: June 2007

We report the case of a middle‐aged female who presented with an acute inferior myocardial infarction treated with intravenous thrombolytics. Immediate coronary angiography demonstrated the presence of a spiral dissection and a large thrombus. After I week of anticoagulation the thrombus had resolved, but a large spiral dissection persisted. This was confirmed by intracoronary ultrasound. We then review the literature on spontaneous coronary arterial dissection.
Preliminary Experience Using Directional Coronary Atherectomy for the Treatment of Acute Myocardial Infarction
Authors: PETRELLA RICHARD W. , FERRARO ROBERT J.
Published: June 2007

Directional coronary atherectomy (DCA) has proven to be an effective treatment for coronary artery disease, both in multiple anatomical locations and in various clinical settings. Little has been published, however, regarding efficacy of DCA for treatment of acute myocardial infarction (MI). This brief report reviews our early experience with DCA in this new role. Twelve patients presenting from April 1993 through February 1994 were identified by review of the DCA Registry at Hamot Medical Center. The group comprised six men and six women, mean age 60 years (range 39–81 years). Patients were administered oral aspirin and intravenous nitroglycerin. Heparin dose was titrated to maintain ACTs > 300 seconds. DCA was performed using 9.5‐, 10‐, and 11 Fr guiding catheters. Seven Fr EX, 7Fr graft, 7Fr surlyn, and 6Fr EX devices were used. Predilation and/or postdilation with balloon angioplasty was performed when clinically indicated. Postprocedure stenoses were determined using comparable orthogonal angiographic views. Lesions were measured by manual caliper assessment and tissue weights were obtained from all specimens. The procedural success rate was 92% (11/12) and the mean postprocedural diameter stenosis was 15% (range – 20% to 52%). The mean tissue weight from atherectomy specimens was 16 mg (range 7.6–35 mg). The mean time from onset of pain to reperfutsion was 2.8 hours (range 40 min to 5.5 hours). Clinical success was achieved in 83% (10/12) of patients. Two deaths occurred in patients presenting with cardiogenic shock. Ten patients experienced no ischemic events, heart failure, or arryhthmias following their interventional procedure. This review is the largest series evaluating the efficacy of DCA in acute MI. The low mean postprocedure diameter stenosis obtained by DCA, as well as the lack of significant recurrent ischemic events postprocedure, may both indicate a potential advantage over the present therapy for acute MI in selected patients. (J Interven Cardiol 1994:7:519–524)
Laser Thrombolysis in Acute Myocardial Infarction: Results of a Clinical Feasibility Study
Authors: den HEIJER PETER , van DIJK RENÉ B. , PENTINGA MILOU L. , HILLEGE HANS L. , LIE KONG I.
Published: June 2007

Laser thrombolysis is a new, experimental, catheter based intervention aimed at selectively removing intracoronary thrombus. This first clinical study was performed to assess the feasibility and safety of laser thrombolysis, as well as its potential therapeutic place in acute myocardial infarction. Eighteen patients with acute myocardial infarction, who were either noncandidates for, or failures on, intravenous fibrinolytic therapy were included for treatment with laser thrombolysis followed by balloon angioplasty. As a result of catheter and technical failures, the laser was actually fired in only 12 patients. Improvement in TIMI flow from grade 0–1 to grade 2–3 was observed in 10 of these 12 patients after laser application. The overall results of 18 patients were: increase in TIMI grade flow from 0.33 ± 0.49 after wire passage to 1.28 ± 1.23 (P = 0.0051) after attempted laser application, and to 2.67 ± 0.97 after PTCA (P = 0.0004). Two patients with previous infarctions died from left ventricular failure despite successful laser thrombolysis. One patient died during emergency bypass surgery after a failed recanalization attempt. Perforation or laser related dissection did not occur. The concept of selective laser thrombus ablation seems to be safe and feasible, but substantial improvements of the laser delivery catheters are needed. Laser thrombolysis is not an effective stand‐alone therapy in acute myocardial infarction, but other possible applications warrant further research and development efforts for this potentially useful interventional tool. (J Interven Cardiol 1994; 7:525–534)
Percutaneous Balloon Mitral Commissurotomy by the Inoue Balloon Resulting in Fatal Cardiac Tamponade: Stitching Phenomenon
Authors: CHINO M. , SATOH T. , YAMANE M. , ADACHI T. , KUWASAKI O. , KUMAMARU H. , NISHIKAWA K.
Published: June 2007

This article presents the first case of fatal pericardial tamponade following immediately after‐ successful percutaneous balloon mitral commissurotonry by the Inoue balloon. The patient had a large right atrium associated with severe tricuspid regurgitation and this led to incorrect atrial puncture (so culled stitching phenomenon) under the Inoue method fir determining the site of fossa ovalis. (J lnterven Cardiol 1994; 7:33–37)
Multivessel Coronary Angioplasty with Anomalous Origin of the Left Main Coronary Artery
Authors: SETH ASHOK , BHASKARAN AMBIKA , GUPTA JAY ANT , BHATIA MADAN LAL
Published: June 2007

We report a case of coronary angioplasty to the right coronary artery, the circumflex, and the left anterior descending artery in a patient with anomalous left main coronary artery arising from the right aortic sinus of Valsalva. At angiographically documented follow‐up of more than 2 years, the patient remains well without restenosis. This case represents the only such report in the literature. Angioplasty hardware was an important factor in successful crossing and dilatation of multiple severe and distal stenoses in the anomalous left system; appropriate technical details are discussed. (J Interven Cardiol 1995;8:359–363)
Balloon‐Expandable Stenting in Pediatric Cardiology
Authors: O'LAUGHLIN MARTIN P.
Published: June 2007

Intravascular stem placement in Pediatric Cardiology has provided one of the most interesting and effective means of catheter treatment of congenital lesions. In the 5 years since it has been performed, balloon‐expandable stem placement has provided relief of many previously unbeatable vascular stenoses and has resulted in improvement of blood flow, reduction of right ventricular pressure and, in many cases, dramatic improvement of symptoms. In this article, the background of balloon‐expandable stent placement is discussed, and specific observations are offered regarding the technique of implantation. The generally excellent results are presented and a number of novel problems and pitfalls are outlined. Finally, a brief summary of the wide ranging applicability of stent implantation is discussed, along with some of the important and imaginative new directions for the therapy. (J Interven Cardiol 1995;8:463–475)
Balloon Angioplasty for Native Coarctation of the Aorta
Authors: MENDELSOHN ALAN M.
Published: June 2007

Balloon angioplasty of native coarctations of the aorta is one of the most controversial facets of the pediatric interventional cardiologist's practice. We have evaluated the history and experimental rationale of this technology. Presently accepted techniques are outlined and controversies intrinsic in performance of this procedure are discussed. Acute, short‐term, and long‐term results are reviewed with particular emphasis on differences in success of the procedure as related to patient age. Common and significant complications are discussed and in some cases compared to analogous surgical complications. Newer technologies and approaches to interventional therapy for coarctation of the aorta are also discussed. (J Interven Cardiol 1995; 8:487–508)
Randomized Trials on PTCA and Stenting in the Treatment of De Novo Coronary Artery Stenosis: An Overview on Existing Data in June 1994
Authors: DEBBAS NADIA M.G. , EECKHOUT ERIC , GOY JEAN‐JACQUES
Published: June 2007

This is a review on prospective randomized comparisons of PTCA and stents in the treatment of de novo native coronary artery lesions. BENESTENT and STRESS, two multicentric studies, used the articulated Palmaz‐Schatz™ stent. In Lausanne, a single center trial limited to right coronary artery lesions, was conducted using the Wiktor™ stent. During the in‐hospital phase, BENESTENT and STRESS showed the composite clinical end point to be less in the stent than in the PTCA groups (P < 0.05). In Lausanne, there was no difference between groups. The incidence of subacute closure was similar with both treatments in three trials. Angiographically, both postpro‐cedural minimal luminal diameter (MLD) and percentage stenosis were larger in the stent group (P < 0.05). At 6 months, in both BENESTENT and STRESS, a composite clinical end point was reached by less stent patients than PTCA patients, with a reduced need for repeat nonsurgical reintervention by Stenting. However, in Lausanne, there was no difference between stent and PTCA groups. At 6 months in both BENESTENT and STRESS, a persistent lower MLD, a larger percentage of stenosis, and a higher incidence of angiographic restenosis were found in the PTCA groups (P < 0.05). In Lausanne, no differences in MLD, percentage stenosis, and angiographic restenosis were found between groups. Effective Stenting of de novo lesions does improve immediate results compared to conventional balloon PTCA. The long‐term outcome of Stenting with Palmaz‐Schatz™ stents is also improved compared to PTCA.
Coronary Laser Angioplasty
Authors: GESCHWIND HERBERT J.
Published: June 2007

Balloon angioplasty was introduced among the armament of therapy for coronary heart disease in 1977 by Gruentzig in Zurich. Since the first case was successful, this method of treatment spread out rapidly so that at the present time, more than 400,000 procedures are being performed per year in the U.S. The reason for such an explosive success includes the relative safety of the procedure, the reduction in cost as compared to surgical bypass procedures, the short in‐hospital stay, and short recovery time.
Endovascular Stents in Pediatric Cardiovascular Medicine
Authors: BENSON LEE N. , NYKANEN DAVID , FREEDOM ROBERT M.
Published: June 2007

Acquired or de novo vascular obstructions can adversely affect the outcomes of management algorithms for children with congenital heart lesions. Although surgical repair is frequently feasible, some acquired or congenital obstructions are difficult to address in the operating theater. Discussed is the recent experience with endovascular stents to relieve such stenoses, and their impact on patient care.
Catheter Ablation of Left Accessory Atrioventricular Connections: The Transseptal Approach
Authors: MONTENERO ANNIBALE SANDRO , CREA FILIPPO , BENDINI MARIA GRAZIA , BELLOCCI FULVIO , ZECCHI PAOLO
Published: June 2007

Background: In the past few years, there has been a relative explosion of activity in the realm of interventional cardiology. The high rate of success of radiofrequency energy ablation have transformed catheter ablation from an investigational procedure into the first‐line therapy for symptomatic Wolff‐Parkinson‐White syndrome. Radiofrequency catheter ablation for preexcitation syndrome is commonly based on a ventricular approach. Such an approach might he associated with the risk of prolonged arterial catheter manipulation, retrograde left ventricular catheterization, and production of multiple, potentially arrhythmogenic, ventricular lesions created during ablation. Potential risks can be avoided using atrial insertion ablation procedures. The transseptal procedure that was developed in the 1950s and 1960s as a diagnostic procedure and then shelved in the 1970s and early 1980s has now come back into prominence as a therapeutic technique in the treatment of valvular heart disease, and then in the ablation of the left accessory atrioventricular connections.

Methods: Atrial aspect of mitral annulus is a relatively smooth, nonobstructed surface that simplifies catheter movement, thereby permitting rapid and accurate accessory pathway location. Although primary use of earliest endocardial retrograde atrial activation as a marker of accessory pathway atrial insertion is sufficiently accurate to permit successful ablation, direct recording of an accessory pathway potential is an important predictor of successful ablation site. Moreover, the analysis of the unipolar atrial electrogram, recorded during sinus rhythm from the tip of the ablation catheter, provides further information for localizing the atrial insertion of the accessory pathways. Shortest atrial‐accessory pathway and negative delta‐accessory pathway intervals have been found to be the best predictors of the successful site.

Results: A 90.5% success of the transseptal approach on an overall population of 328 patients, higher for overt than for concealed pathways, is comparable with the results of the retrograde. Complications are 0.5%. Conclusion: In conclusion, the transseptal approach for ablation at the atrial site is very safe and highly effective, and avoids prolonged arterial cannulation and catheter manipulation in the ascending aorta and left ventricle.
New Horizons in Catheter Ablation
Authors: HAINES DAVID E. , NATH SUNIL
Published: June 2007

Catheter ablation has evolved into the dominant therapeutic modality in the treatment of a variety of arrhythmias, particularly supraventricular arrhythmias with the mechanisms of atrioventricular (AV) nodal reentry and AV reciprocating tachycardia via an accessory pathway. The mode of catheter ablation used in the great majority of cases is radiofrequency (RF) catheter ablation. This technology is well‐suited for the above arrhythmias because the targets and the RF lesions are both small and discrete. Using temperature monitoring may improve the outcome of these procedures by decreasing procedure time and incidence of coagulum formation on the catheter after a sudden rise in electrical impedance. New RF catheter designs and new modalities of creating catheter‐induced focal myocardial injury will allow operators to have improved success with the ablation of less approachable arrhythmias, including atrial flutter and reentrant ventricular tachycardia. Studies are currently underway to create a catheter based “maze” procedure for the treatment of atrial fibrillation. As techniques and technologies evolve, a greater proportion of patients with symptomatic or threatening arrhythmias may be approached with catheter ablation as a curative or palliative procedure.
Is There Space for Surgery in the Treatment of Tachyarrhythmias?
Authors: HAUER RICHARD N.W.
Published: June 2007

Curative treatment of both supraventricular and ventricular tachyarrhythmias started with the introduction of surgical therapy. Surgical treatment modalities were often very successful and associated with low mortality and morbidity, especially in patients with various supraventricular tachyarrhythmias. However, results were acceptable in patients with ventricular tachyarrhythmias, with often a very complex and extended arrhythmogenic area associated with structural heart disease. Because of the development and proven effectiveness of catheter ablation and defibrillator implantation, the role of surgical therapy became limited. In the treatment of supraventricular arrhythmias, surgical therapy is an option after failure of catheter ablation. Since His‐bundle catheter ablation is only a palliative treatment for atrial fibrillation, the potentially curative Maze operation may be an acceptable alternative. However, its potential against formation of intracavitary thrombi has not yet been proven. In the treatment of ventricular tachyarrhythmias, ischemia related polymorphic ventricular tachycardia and ventricular fibrillation can be treated very effectively by revascularization. Map‐guided surgery is an appropriate treatment modality for patients with monomorphic ventricular tachycardia and an extended arrhythmogenic area. However, patients with very poor left ventricular function may have an unacceptable perioperative risk. In patients with congenital long QT syndrome who are refractory to beta blocking agents, left‐sided sympathectomy is the most appropriate choice.
Angiographic Results and Elastic Recoil Following Coronary Excimer Laser Angioplasty with Saline Perfusion
Authors: PIZZULLI LUCIANO , JUNG WERNER , PFEIFFER DIETRICH , FEHSKE WOLFGANG , LÜDERITZ BERNDT
Published: June 2007

Recent experiments have demonstrated that pressure waves of several hundred atmospheres, which occur during excimer laser coronary angioplasty (ELCA), are reduced while ablating in saline in comparison to blood or contrast medium. We report the procedural outcome of ELCA (XeCI laser operating at 308 nm, 25–40 Hz, 40–60 mJ/mm2 fluence, and 135 nsec/pulse) performed with a modified saline infusion protocol (two operator technique, flush, and continuous application of saline through the guiding catheter immediately prior and during the whole losing procedure). We studied 48 patients (34 males, 14 females; mean age: 61 ± 6 years; 18 occlusions, 30 stenoses [> 60% diameter stenosis]) with 10 type A, 17 type B, and 21 type C lesions. Laser success (> 20% increase in minimal luminal diameter [MLD]) was achieved in 41 patients (85.4%), and procedural success (< 50% residual stenosis) in 44 patients (91.6%). The MLD increased from 0.37 ± 0.12 to 1.63 ± 0.35 mm (P < 0.001) following laser ablation, and to 2.30 ± 0.34 mm (P > 0.01) after percutaneous transluminal coronary angioplasty (PTCA). The mean percentage stenosis decreased from 81%± 6% (baseline) to 48%± 12% (P < 0.001) after laser ablation, and to 29%± 10% (P < 0.01) following PTCA. The mean diameter of the laser‐catheter (LC) was 1.54 ± 0.2 and the mean diameter of the inflated balloon at maximum pressure was 2.7 ± 0.25 mm. Thus, the elastic recoil (ER) following balloon deflation was 15%± 9%, and below the reported ER for PTCA. Two major dissections occurred following ELCA; one patient required bypass surgery and developed a Q wave myocardial infarction (Ml), and one patient was successfully treated with stent implantation following abrupt closure. There were no in‐hospital deaths, further Q wave MIs, and/or perforation. In conclusion, ELCA with concomitant saline infusion is effective, safe, and easy to perform. The use of this ablation procedure reduces the rate of significant dissections, favors effective tissue ablation, and thus may in part be responsible for a reduced amount of elastic recoil following additional balloon angioplasty. (J Interven Cardiol 1996;9:9–18)
Catheter Ablation for the Common Type of Atrial Flutter: Where Do We Stand?
Authors: SAOUDI NADIR , NAIR MOHAN , POTY HERVÉ , ANSELME FRÉDÉRIC , LETAC BRICE
Published: June 2007

Atrial flutter is a reentrant tachycardia that originates in the right atrium. The wave front of atrial flutter travels craniocaudally along the anterolateral wall of the right atrium, surrounds the inferior vena cava, and crosses the region between this structure and the tricuspid ring before closing the. circuit after upward septal propagation. The area located between the tricuspid annulus and the inferior vena cava has been proposed as an ideal target for ablation because it appears to be an isthmus that is an obligatory route for closing the inferior part of the arrhythmia circuit. Various publications dealing with radiofrequency ablation of this tachycardia have dealt with different approaches, and a wide range of acute and chronic success rates have been reported. The main difficulty in interpreting the results of this series is the lack of a carefully defined patient selection, technique description, and follow‐up protocol. In almost all of these series it clearly appears that a significant number of late flutter recurrences occur in these patients, in addition to the emergence of previously unknown atrial fibrillation. Many recent reports, where ablation has been targeted at the inferior vena cava‐tricuspid annulus isthmus, have shown a high rate of acute, success. In our experience, the procedure seems to be facilitated by the use of extra large tip (8‐mm) ablation catheters that allow the use of higher power outputs. Careful mapping of the ablation site has shown that creation of complete bidirectional block at the isthmus is important for prevention of late recurrences. Further technological improvements should aim at developing energy delivery systems that allow controlled destruction of wide areas of the atrial myocardium. (J Interven Cardiol 1996;9:35–44)
Modulation of Healthy Pig Coronary Arteries by Self‐Expanding Stents
Authors: WAALE WENDY H. E. , VAN DER VEEN FREDERIK H. , LEEUWEN CEES VAN. , LANKVELD MONIEK , HAVENITH MIEK , BÄR FRITS W. , OPPEN JAN VAN. , WELLENS HEIN J. J.
Published: June 2007

Objectives: To evaluate the expansion ratio of a self‐expanding stem over time, and the chronic effect of stent pressure on the vessel wall. Methods: Self‐expanding stents, developed by Medtronic Inc. (Minneapolis, MN, USA) and the Rouen group (Letac, Cribier, France), were implanted in 21 normal pig coronary arteries. Animals were sacrificed after recatheterization at 1 day (group I, n = 4), I week (group 2, n = 3), 3 weeks (group 3, n = 5), or 8 weeks (group 4, n = 4). Histological morphometry of the vessel medial and neointimal layers was performed. Changes were related to the, stent diameter and. its force on the vessel wall. Results: The stent expansion ratio gradually increased from 73% to 93% after 8 weeks, which implicates that radial force decreased concomitantly from 0.10 N to 0.03 N. Media compression under the rods ranged from 4l%‐66% immediately after stent implantation. The mean compression was unrelated to stent expansion and remained nearly the same (40%‐50%) during follow‐up. Individual media rod compression ranged from 5%‐95%. The neointimal layer on top of the rods increased until the third week after stent implant (neointimal thickness 211 ± 108 μm). The layer significantly decreased at 8 weeks (neointimal thickness 65 ± 9 μm). The cross‐sectional neointimal area increased gradually only at the end of the stent during the 8‐week follow‐up. Conclusions: The self‐expanding stent implanted in normal pig coronary arteries reached a gradual relaxation state 8 weeks after implantation due to the persistent radial force. This radial force induces medial wall compression, which was only positively related to the thickness of the neointimal layer at 3 weeks after implant. (J Interven Cardiol 1996;9:45–52)
Directional Atherectomy of Complex Coronary Disease: Lesion Specific Outcomes and Treatment Strategies
Authors: GARRATT KIRK N. , BELL MALCOLM R. , HOLMES DAVID R.
Published: June 2007

Complex coronary disease may be defined as a disease in which one or more morphological features are present that are known to be associated with an increased risk of complications during angioplasty. Directional coronary atherectomy may be useful in treating such complex lesions. We review our experiences with complex coronary lesions treated with directional coronary atherectomy. Outcome data are presented within the context of the reported literature, and strategies for approaching complex disease with directional atherectomy are suggested. (J Interven Cardiol 1996;9:135–144)
Balloon Angioplasty and Endoluminal Stenting of Clinically Significant Human Carotid Artery Occlusive Lesions: A New Model for Ex Vivo Morphological Analysis
Authors: LYON ROSS T. , MARIN MICHAEL L. , VEITH FRANK J.
Published: June 2007

The successful use of balloon angioplasty and intravascular stenting for the treatment of atherosclerotic lesions in the coronary and peripheral arteries has recently led to the application of these techniques to the management of carotid artery stenosis. We have, therefore, attempted to determine the local consequences of these interventions in the carotid circulation by developing an ex vivo model of simultaneous balloon angioplasty and endoluminal stenting of clinically significant human internal carotid artery occlusive lesions. The following report describes this model and discusses the related clinical issues.
Transluminal Angioplasty of the Extracranial Carotid Artery: Indications and Technique—A Multicenter Interventional Neuroradiologist's Perspective
Authors: HALBACH VAN V. , HIGASHIDA RANDALL T. , TSAI FONG Y. , DOWD CHRISTOPHER F. , HIESHIMA GRANT B.
Published: June 2007

The authors report their experience with transluminal angioplasty of the extracranial carotid artery over the past 14 years. The angioplasty sites included the common carotid artery in 59 patients, the internal carotid artery in 55 patients, and the external carotid artery in 11 patients. The indications for treatment included patients who harbored symptomatic stenosis of 70% or greater, with the majority failing medical therapy and considered poor surgical candidates.
Characterization of a Precocious New Lesion Distal to a Stent Site by Atherectomy
Authors: PHILLIPS PAUL S. , ALFONSO FERNANDO , ARAGONCILLO PALOMA , GOICOLEA JAVIER , HERNANDEZ ROSANA , SEGOVIA JAVIER , BANUELOS CAMINO , FERNANDEZ‐ORTIZ ANTONIO , MACAYA CARLOS
Published: June 2007

A 58‐year‐old woman presented with a new rapidly progressive lesion distal to a stent. This lesion was treated with atherectomy through the stem in order to characterize it pathologically. The aggressive proliferative response discovered suggested that this unusually distal lesion was produced by the trauma of her previous angioplasty.
Left Ventricular Wall‐Motion Changes During Eccentric Ventricular Activation in Hypertrophic Obstructive Cardiomyopathy Patients
Authors: JEANRENAUD XAVIER
Published: June 2007

Permanent atrial synchronized right ventricular pacing (RVP) has been shown to induce subaortic pressure gradient reduction and to lead to clinical improvement in patients suffering from hypertrophic obstructive cardiomyopathy (HOCM). It has therefore been proposed as an alternative therapy to surgery for patients refractory to drug therapy. The mechanisms underlying these beneficial effects are, however, unclear, but the electrically induced alteration of left ventricular (LV) activation sequence appears to play a major role. In this article, I summarize the data relative to the specific effects of RVP and left bundle branch block on LV contraction in normal subjects and in cardiomyopathies other than hypertrophic. I also review the characteristics of regional wall motion in HOCM, then the current data on left ventricular wall‐motion changes during eccentric ventricular activation in HOCM patients equipped with a dual chamber pacemaker. On the basis of the most recent studies, preexcitation of the interventricular septum by a RV apical stimulation alters septal motion by reducing its motility or by inducing a paradoxical motion, which enlarges the LV outflow tract and thereby reduces subaortic obstruction.
Importance of Atrial Contraction in Hypertrophic Obstructive Cardiomyopathy: Implications for Pacing Therapy
Authors: DAUBERT J. CLAUDE , PAVIN DOMINIQUE , GRAS DANIEL , PLACE CHRISTIAN DE. , LECLERCQ CHRISTOPHE , LE BRETON HERVÉ , MABO PHILIPPE
Published: June 2007

Hypertrophic cardiomyopathy is a primary myocardial disease characterized anatomically by left ventricular (LV) asymmetric hypertrophy and pathophysiologically by normal or even supernormal systolic ejection performance contrasting with impaired diastolic function. Altered ventricular relaxation tends to reduce the contribution of rapid ventricular filling to total LV filling volumes. Consequently, the contribution of left atrial (LA) contraction can be significantly increased. In some patients LV filling, and thus stroke volume, critically depend upon atrial systole. These data may have important clinical implications especially in patients treated with permanent cardiac pacing. Preserving a fully efficient LA contribution to LV filling is probably a key point in those patients.