Crosswire for recanalization of total occlusive coronary arteries

Coronary angioplasty of total occlusions is technically difficult and is associated with limited success rates. The procedural outcome is mainly determined by the underlying pathological process. Recanalization of total occlusions is aimed at finding the passage with least resistance, without causing dissection or perforation. Several techniques have been advocated to improve the overall success rate. Recently, a new 0.014" Nitinol wire (Crosswire, Terumo) has been introduced as a tool, to achieve higher success rates for total occlusion angioplasty. The wire consists of an extremely flexible Nitinol-core, a platinum/iridium coil at the distal tip, and a hydrophilic polymer coating. Balloon angioplasty was attempted in 30 totally occluded coronary arteries with mean age of occlusion being 5 +/- 4 months (range 2-14 months). The initial five procedures were performed following failure of the conventional angioplasty guidewires. Subsequently, Cross-wire was used electively in all the cases. The lesion was crossed successfully in 90% (27/30) cases. Dissection of the coronary artery with subintimal entry was seen in two (7%) cases, and the rest (three cases) could not be crossed. Balloon angioplasty and stenting (n = 21) were performed with good immediate angiographic results. There were no myocardial infarctions or deaths. Fourteen of 16 patients, who had completed 6 months follow-up, were asymptomatic. Angiographic evidence of in-stent restenosis was demonstrable in one case. Successful recanalization of total coronary occlusions by using Cross-wire can be expected in 83% cases, with reasonable safety.     

Prospective, randomized trial of prolonged intracoronary urokinase infusion for chronic total occlusions in native coronary arteries

OBJECTIVES: The purpose of this study was to determine the safety and efficacy of three dosing regimens of intracoronary urokinase for facilitated angioplasty of chronic total native coronary artery occlusions. BACKGROUND: Percutaneous transluminal coronary angioplasty of chronically occluded (>3 months) native coronary arteries is associated with low initial success secondary to an inability to pass the guide wire beyond the occlusion. METHODS: Patients were enrolled if a chronic total occlusion >3 months old could not be crossed with standard angioplasty equipment. Of the 101 patients enrolled, 41 had successful guide wire passage and were excluded from urokinase treatment. The remaining 60 patients were randomized to receive one of three intracoronary dosing regimens of urokinase over 8 h (group A = 0.8 million U; group B = 1.6 million U; group C = 3.2 million U), and angioplasty was again attempted after completion of the urokinase infusion in 58 patients. RESULTS: Coronary angioplasty was successful in 32 patients (53%) (group A 52%, group B 50%, group C 59%, p = 0.86). This study had a 90% power to detect at least a 50% difference between dosing groups at alpha 0.05. Bleeding complications requiring blood transfusion did not differ significantly among the dosing groups (A 0%, B 15%, C 6%, p = 0.14), although major bleeding episodes were less common in group A (p < 0.05). There were no major procedural or in-hospital complications. Angiographic follow-up in 69% of the patients with successful angioplasty revealed target vessel patency in 91% but an angiographic restenosis rate of 59%. CONCLUSIONS: A prolonged supraselective intracoronary infusion of urokinase can be safely administered and may facilitate angioplasty of chronic total occlusions. Lower doses of urokinase are equally effective and result in fewer bleeding complications than do higher dosage regimens. Vessel patency is frequently maintained, but restenosis remains a problem.     

Direct percutaneous transluminal coronary angioplasty in acute myocardial infarction. Predictors of short-term outcome and the impact of coronary stenting. Study Group of The Arbeitsgemeinschaft Leitender Kardiologischer Krankenhaus?rzte (ALKK)

BACKGROUND: Direct percutaneous transluminal coronary angioplasty (PTCA) is widely accepted in the treatment of acute myocardial infarction since excellent results had been reported from several small randomized trials. Less favourable results were observed in large-scale registries. In particular, the use of stents in acute myocardial infarction has become common practice without documented evidence of clinical efficacy. METHODS: Data were analysed from a registry of all consecutive percutaneous transluminal coronary angioplasty procedures from 62 centres in Germany, including 2331 direct percutaneous transluminal coronary angioplasty in acute myocardial infarction from July 1994 to April 1997. RESULTS: The overall angiographic success rate of percutaneous transluminal coronary angioplasty, defined as complete antegrade perfusion of the infarct vessel, was 87%. In-hospital mortality was 11.2%. The most important predictor of death was the presence of cardiogenic shock in 15% of patients, of whom 52% died. Mortality in patients without shock was 3.9%. Failed percutaneous transluminal coronary angioplasty was associated with a mortality of 36%. Further independent predictors of death were older age, multivessel disease, and anterior myocardial infarction. Stents were used in 4.1% of the procedures in 1994, increasing to 53% in 1997. However, this was not accompanied by improved clinical outcome. Mortality with coronary stenting was 9.9% vs 11.6% without stents (ns). CONCLUSIONS: Direct percutaneous transluminal coronary angioplasty is a valuable treatment strategy in acute myocardial infarction, although the results are less exceptional than reported from some highly specialized centres. Failed percutaneous transluminal coronary angioplasty seems to be harmful, thus outweighing much of the benefit from successful procedures. Stents did not improve the clinical outcome significantly, despite technically successful placement in 98%. Mortality from cardiogenic shock continues to be excessively high despite direct PTCA.     

Radiofrequency thermal balloon coronary angioplasty: a new device for successful percutaneous transluminal coronary angioplasty

OBJECTIVES: The purpose of this study was to evaluate the effects of thermal balloon percutaneous transluminal coronary angioplasty using radiofrequency energy in the treatment of patients with failed coronary angioplasty and complex lesions. In addition, we evaluated restenosis after radiofrequency thermal balloon applications. BACKGROUND: The efficacy of coronary angioplasty is limited by the relatively low success rate in complex lesions and the high frequency of restenosis. Few reports have studied the combined effects of pressure and laser thermal energy. This study describes a new device for coronary angioplasty using radiofrequency thermal energy. METHODS: Thirty-two patients with failed conventional coronary angioplasty or complex lesions were treated with radiofrequency thermal balloon coronary angioplasty. Radiofrequency energy was delivered up to 11 times in exposures ranging from 30 to 60 s in duration. This combined effect allowed the vascular wall to be heated to temperatures ranging from 60 to 70 degrees C. Follow-up coronary angiography was performed, on average, 6 months after the procedure. RESULTS: Successful radiofrequency coronary angioplasty was achieved in 28 (82%) of 34 lesions. There was one abrupt coronary artery occlusion (3%) and no death, perforation or dissection. Angiographic restenosis occurred in 14 (56%) of 25 lesions. CONCLUSIONS: In patients with failed coronary angioplasty and difficult complex lesions, radiofrequency coronary angioplasty could potentially improve angioplasty success rates and may have important implications for bailout cases with abrupt occlusion. However, restenosis remains a significant problem.     

Results of the multicenter natural interferon-alpha treatment for chronic hepatitis C: correlation between total dose, administration periods and efficacy of therapy. Keio Natural IFN-alpha study group

From January 1993 to December 1995, intraarterial catheter guided urokinase infusion was used as an initial approach in the management of 29 episodes of infrainguinal graft thrombosis (12 venous and 17 prosthetic grafts) in 27 patients. The infusion catheter was embedded inside the occluding clot which was infiltrated by 225.000 U urokinase from distal to proximal. Local low-dose urokinase (1.000 U/kg/hr) was continued for a mean of 39 hours. By this regimen, prompt relief of ischaemia was achieved in 69% (20/29) of cases. Complete recanalization was obtained in 79% of cases. In six cases, the graft remained totally (n = 3) or partially (n = 3) occluded. Two of these patients benefited from secondary surgery, two improved clinically by conservative treatment, and two required amputation. In the 23 successful cases, thrombolysis unmasked an underlying flow-limiting stenosis in 83% (19/23), that was subsequently corrected by percutaneous balloon angioplasty (n = 15), by surgery (n = 3), or by a combination of both (n = 4). One early rethrombosis resulted in an amputation. The immediate limb-salvage rate was 89% (26/29). Surgical intervention was avoided in 17 cases (58%). The main hospital stay was 13 days. The short-term follow-up (mean of 17 months) reveals a high early rethrombosis rate (8/23 or 35%) within one year. Four of these repeated graft failures evolved to amputation. At one year, the overall limb salvage rate dropped to 79%. Thrombolytic management of infrainguinal occluded bypass grafts gives excellent initial technical results (79%), minimizing the need for major surgical revision. It is however characterized by a high procedure-related morbidity (21%). These immediate favourable results are not longstanding. Diffuse graft disease, limited outflow and high recurrence rate of anastomotic stenoses after balloon angioplasty explain poor long-term results after thrombolysis of failed grafts.     

Cortical influences on cervical motoneurons in the rat: recordings of synaptic responses from motoneurons and compound action potential from corticospinal axons

Restenosis after successful coronary angioplasty (PTCA) occurs in 25-35% of all procedures. To date, most pharmacologic strategies have failed to reduce the restenosis rate significantly. However, recent studies have suggested a potential benefit of dietary supplementation with omega-3 fatty acids (fish oil) on restenosis following PTCA. The benefit of omega-3 polyunsaturated fatty acids on the incidence of coronary artery restenosis following elective PTCA was assessed in 212 consecutive patients (41 female, 171 male). Following a successful angioplasty, 204 patients received a dietary supplementation with either nine capsules containing fish oil (3.15 g omega-3 fatty acids) or nine placebo capsules containing olive oil. Treatment was started immediately after PTCA and maintained over 4 mon. Compliance was assessed by analysis of lipid fatty acids prior to angioplasty and at 4 mon follow-up. The angiographically determined incidence of restenosis (stenosis diameter > 50%) was 31.2% per lesion in patients receiving fish oil and 33.7% in patients receiving olive oil. Gross progression of coronary artery disease in vessels not subjected to angioplasty was 17% and 16%, respectively. In conclusion, low dose fish oil supplementation begun on the day of a successful coronary angioplasty failed to demonstrate any effect on coronary artery restenosis.     

Detection of severity of coronary stenosis by quantitative myocardial tomography with Tc-99m-MIBI at rest

To evaluate the role of myocardial tomography with Tc-99m-MIBI (MB) in detecting abnormal coronary arteries, 34 patients with myocardial infarction underwent resting quantitative SPEC with MB and coronary arteriography within one month. When segmental MB uptake was < 560% of the left ventricular peak activity, there was 88% probability that a totally occluded or severely stenosed coronary artery (stenosis > 90%) was involved. There was 82% probability of finding no significant stenosis of coronary arteries in the normal myocardial segments. In the myocardial segments supplied by occluded coronary arteries, there was significantly higher MB uptake in the segments with good collateral circulation as compared with those subtended by a vessel totally occluded with poor collateral circulation (P < 0.05). The sensitivity and specificity of detecting abnormal coronary artery by quantitative analysis of myocardial tomography was 87% and 90% respectively. It is suggested that quantitative analysis of myocardial tomography with MB can differentiate between myocardial segments supplied by severely stenosed and normal coronary artery and evaluate the existence of collateral circulation.     

Elevation of serum luteinizing hormone levels during hydrocortisone treatment in infant girls with 21-hydroxylase deficiency

This preliminary study in 20 patients demonstrated that ultrasonic coronary angioplasty in the setting of bypass grafting is feasible, safe, and able to recanalize atherosclerotic vessels. Shorter monorail probes were superior to longer probes without guidewires in terms of success of vessel recanalization; >95% of particle debris was <25 microm in size.     

The relation between multiple sleep latency test findings and the frequency of apneic events in REM and non-REM sleep

OBJECTIVES: The purpose of this prospective study was to evaluate the immediate results and the 6-month angiographic recurrent restenosis rate after balloon angioplasty for in-stent restenosis. BACKGROUND: Despite excellent immediate and mid-term results, 20% to 30% of patients with coronary stent implantation will present an angiographic restenosis and may require additional treatment. The optimal treatment for in-stent restenosis is still unclear. METHODS: Quantitative coronary angiography (QCA) analyses were performed before and after stent implantation, before and after balloon angioplasty for in-stent restenosis and on a 6-month systematic coronary angiogram to assess the recurrent angiographic restenosis rate. RESULTS: Balloon angioplasty was performed in 52 patients presenting in-stent restenosis. In-stent restenosis was either diffuse (> or =10 mm) inside the stent (71%) or focal (29%). Mean stent length was 16+/-7 mm. Balloon diameter of 2.98+/-0.37 mm and maximal inflation pressure of 10+/-3 atm were used for balloon angioplasty. Angiographic success rate was 100% without any complication. Acute gain was lower after balloon angioplasty for in-stent restenosis than after stent implantation: 1.19+/-0.60 mm vs. 1.75+/-0.68 mm (p=0.0002). At 6-month follow-up, 60% of patients were asymptomatic and no patient died. Eighteen patients (35%) had repeat target vessel revascularization. Angiographic restenosis rate was 54%. Recurrent restenosis rate was higher when in-stent restenosis was diffuse: 63% vs. 31% when focal, p=0.046. CONCLUSIONS: Although balloon angioplasty for in-stent restenosis can be safely and successfully performed, it leads to less immediate stenosis improvement than at time of stent implantation and carries a high recurrent angiographic restenosis rate at 6 months, in particular in diffuse in-stent restenosis lesions.     

Immediate angioplasty results of total coronary artery occlusion in Thai population

Attempted angioplasty of totally occluded vessels may be done. However, a lower success rate is expected compared to those with subtotal occlusion. The complication rate is comparable to that of partial occlusion in experienced hands.     

Excimer laser-facilitated angioplasty for undilatable coronary narrowings

Calcified and fibrotic coronary artery lesions cannot always be dilated with conventional balloon angioplasty even at high pressures. This study examines the success of excimer laser facilitated angioplasty in 38 lesions in 37 patients with lesions that failed balloon angioplasty alone.     

The influence of coffee with milk and tea with milk on the bioavailability of tetracycline

BACKGROUND: At the initial stages of percutaneous transluminal coronary angioplasty (PTCA), several studies reported on the feasibility of coronary artery incision and dilatation leading to the extension of the PTCA technique. HYPOTHESIS: This study was designed to determine the immediate and chronic results of cutting balloon (CB) angioplasty. METHODS: This procedure was performed on 127 lesions in 110 patients (male 83%, age 61.8 +/- 9.3 years). RESULTS: The overall procedural success rates for the CB were 93.7% (119 lesions) and 92.7% (102 patients), while solitary CB without pre- and/or postdilatation was 76.4% (91 lesions). There was one major in-hospital complication (Q-wave myocardial infarction, 0.9%), but there were no deaths or emergency coronary artery bypass graftings. Significant angiographic dissections (> or = grade C) occurred in four patients, and coronary perforation occurred in one. The successfully treated CB group (95 lesions) was matched with the successful conventional angioplasty group (PTCA group) for chronic result assessment in regard to reference vessel size and lesion characteristics. In the CB group, postprocedural minimal luminal diameters were significantly larger and the percentage of stenosis at the stenotic site was significantly lower compared with the PTCA group. Restenosis occurred in 22 lesions (23.1%). This showed a significantly lower restenosis rate compared with the PTCA group (42.1%). In addition, the restenosis rate of the CB without inclusion of the pre- and/or postdilatation-treated lesions was 19.7%. CONCLUSIONS: (1) Cutting balloon angioplasty procedures can be performed with high success rates with few major inhospital events. (2) The restenosis rate in the CB group was significantly lower compared with the PTCA group.     

Effects of late percutaneous transluminal coronary angioplasty of an occluded infarct-related coronary artery on left ventricular function in patients with a recent (< 6 weeks) Q-wave acute myocardial infarction (Total Occlusion Post-Myocardial Infarction Intervention Study [TOMIIS]--a pilot study)

The effect of late percutaneous transluminal coronary angioplasty (PTCA) of an occluded infarct-related artery on left ventricular ejection fraction was studied in patients with a recent, first Q-wave myocardial infarction in a prospective, randomized study. Forty-four patients (31 men and 13 women, mean age 58 +/- 12 years) with an occluded infarct-related coronary artery were randomized to PTCA (n = 25) or no PTCA (n = 19). Patients received acetylsalicylic acid, a beta blocker and an angiotensin-converting enzyme inhibitor unless contraindicated. Left ventricular ejection fraction was determined at baseline and 4 months. Coronary angiography was repeated at 4 months. Baseline ejection fraction measured 20 +/- 12 days after myocardial infarction was 45 +/- 12% in both groups. PTCA was performed 21 +/- 13 days after the event. The primary PTCA success rate was 72%. One patient in each group died before angiographic follow-up, which was completed in 37 of the remaining 42 patients (88%; 21 with and 16 without PTCA). At 4 months, the infarct-related artery was patent in 43% of PTCA patients and in 19% of no PTCA patients (p = NS). Reocclusion occurred in 40% of patients after successful PTCA. Secondary analyses showed that the change in left ventricular ejection fraction was significantly greater in patients with a patent infarct-related artery (+9.4 +/- 6.2%) than in those with an occluded artery (+1.6 +/- 8.8%; p = 0.0096). Baseline ejection fraction also independently predicted improvement in left ventricular ejection fraction (p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Cytochrome P450 2E1 mRNA in the rat prostate: detection and quantitation by competitive reverse transcription and polymerase chain reaction

Conventional balloon angioplasty treatment of aorto-ostial stenoses in native coronary arteries and saphenous vein grafts is associated with a low primary success rate, a high complication rate and a high incidence of restenosis. The short-term outcome of Palmaz-Schatz stent implantation in aorto-ostial lesions was compared with that of balloon angioplasty. Thirteen patients underwent stent implantation for 13 de novo lesions (four in the left main coronary trunk, two in the right coronary artery, seven in the vein graft) between January 1994 and December 1995. Fourteen patients underwent balloon angioplasty for 14 de novo lesions (five in the left main coronary trunk, four in the right coronary artery, five in the vein graft between January 1986 and April 1992. Both groups had similar clinical characteristics. Initial success was obtained in all patients in the stent group, compared with 71% of the balloon angioplasty group. Insufficient dilation was the main cause for such failure in the balloon angioplasty group. Baseline reference diameters were similar (3.40 +/- 0.65 mm in the stent group vs 3.36 +/- 0.42 mm in the balloon angioplasty group) and there was no difference in baseline minimal luminal diameter (1.41 +/- 0.74 vs 1.08 +/- 0.56 mm). Minimal luminal diameter was significantly greater in the stent group than in the balloon angioplasty group at both post-procedure and follow-up examinations (post: 3.36 +/- 0.58 vs 2.69 +/- 0.45 mm, p < 0.01; follow-up: 2.33 +/- 0.96 vs 1.52 +/- 0.68 mm, p < 0.05). There was no subacute occlusion in either group. The overall angiographic restenosis rate (> 50% stenosis) was lower in the stent group (17%) than in the balloon angioplasty group: the restenosis rates of native lesions were 0% in the stent group and 40% in the balloon angioplasty group; those of saphenous vein graft lesions were 33% in the stent group and 50% in the balloon angioplasty group. Although the number of patients was limited, these results suggest that Palmaz-Schatz stent implantation may be a safe and effective strategy for treating aorto-ostial lesions in both native coronary arteries and saphenous vein grafts.     

Angioplasty of the occluded internal carotid artery

PURPOSE: To review patients who have presented with acute strokes from a middle cerebral artery occlusion in whom in addition to the middle cerebral artery thromboembolus, an internal carotid artery occlusion has been present, and in whom angioplasty of these totally occluded internal carotid arteries has bee n successful. METHODS: We reviewed retrospectively our experience in treating a cute stroke patients with intracranial, intraarterial urokinase. Six of 27 patients had internal carotid artery occlusions in addition to middle cerebral artery occlusions. Two patients presented with spontaneous carotid dissections for wh ich no further intervention from the ipsilateral internal carotid artery was attempted. In the remaining four internal carotid artery occlusions secondary to atherosclerotic disease, standard guide wires and catheters were negotiated across the level of the internal carotid artery occlusion, which expedited intracranial catheterization for thrombolysis. Subsequently, angioplasty of the internal carotid artery was performed. RESULTS: All four occluded internal carotid arteries could be traversed. No new neurologic deficits occurred. No vascular injuries occurred. No deaths occurred. Four- to 6-month follow-up showed all four internal carotid arteries remained patent. CONCLUSION: In acute occlusions of the internal carotid artery from atherosclerosis, the occluded vessel can sometimes be recanalized with low morbidity. In addition, endovascular access to the intracranial circulation can be expedited by using the recanalized internal carotid artery.     

Recanalization of totally occluded saphenous vein grafts using local urokinase delivery with the Dispatch catheter

Current techniques for the percutaneous revascularization of totally occluded vein grafts are limited by a low initial success rate, a significant incidence of distal embolization, and a high rate of early graft reclosure. This case report describes two patients in whom graft recanalization was attempted with the combined use of balloon angioplasty/intra-graft stent placement and local urokinase delivery using a new angiotherapy catheter. Successful recanalization was achieved in both patients without major complications, in spite of a large thrombus burden as demonstrated by angiography.     

Are directional coronary atherectomy and Palmaz-Schatz stent more efficacious than conventional balloon angioplasty for treating de novo coronary artery lesions?

It is unclear whether new devices such as directional coronary atherectomy (DCA) or Palmaz-Schatz stent implantation improve long-term outcomes compared with conventional balloon angioplasty in patients with stable angina and de novo coronary artery lesions of type A or type B except for complete occlusive lesions investigated by the American College of Cardiology/American Heart Association task force on percutaneous transluminal coronary angioplasty. A total of 146 patients with stable angina and simple lesions were assigned to either conventional balloon angioplasty (62 patients), DCA (50 patients), or Palmaz-Schatz implantation (34 patients). The acute results and late outcomes were assessed by coronary angiography. The results of the three procedures were similar with respect to procedural success and complications. Patients who underwent stenting or DCA had a larger immediate increase in the diameter of the lumen and a larger luminal diameter immediately after the procedure than those who underwent balloon angioplasty. At six months follow-up, the patients treated by stenting continued to have a larger luminal diameter and a lower rate of restenosis than those treated with balloon angioplasty (2.30 +/- 0.66 vs 1.85 +/- 0.83 mm, p < 0.005; 5.9% vs 29%, p < 0.05) and DCA (2.30 +/- 0.66 vs 1.90 +/- 0.96 mm, p < 0.05; 5.9% vs 24%, NS). The patients treated with balloon angioplasty had a smaller late loss than those treated with DCA or Palmaz-Schatz stent. The patients treated with DCA had a larger loss index than those treated with balloon angioplasty or Palmaz-Schatz stent. Stenting was a significant factor in decreasing the rate of restenosis by logistic regression analysis, compared with balloon angioplasty. The angiographic outcomes were better in patients who received a stent than in those who received other treatments. This study suggests that even lesions stable for treatment by balloon angioplasty and DCA can also be treated with Palmaz-Schatz stents.     

Procedural results and late clinical outcomes following multivessel coronary stenting

OBJECTIVES: To evaluate in-hospital and long-term clinical outcomes in a large consecutive series of patients undergoing percutaneous multivessel stent intervention. BACKGROUND: High restenosis and recurrent angina rates have limited the clinical outcomes of multivessel coronary angioplasty before stents were available to improve angioplasty results. METHODS: We evaluated in-hospital and long-term clinical outcomes (death, Q-wave myocardial infarction [MI], and repeat revascularization rates at one year) in 398 consecutive patients treated with coronary stents in two (94% of patients) or three native arteries, compared to 1,941 patients undergoing stenting procedure in a single coronary artery between January 1, 1994 and August 29, 1997. RESULTS: Overall procedural success was obtained in 96% of patients with two- or three-vessel stenting and in 970% of patients with single-vessel stent intervention (p = 0.36). Procedural complications were also similar (3.8% for multivessel versus 2.9% for single vessel, p = 0.14). During follow up, target lesion revascularization was 15% in multivessel and 16% in single-vessel interventions (p = 0.38), and repeat revascularization (calculated per treated patient) was also similar for both groups (20% vs. 21%, p = 0.73). There was no difference in death (1.4% vs. 0.7%, p = 0.26), and Q-wave MI (1.2% vs. 0%, p = 0.02) was lower following multivessel interventions. Overall cardiac event-free survival was similar for both groups (p = 0.52). CONCLUSIONS: Unlike previous conventional angioplasty experiences, multivessel stenting has (1) similar in-hospital procedural success and major complication rates and (2) similar long-term (one year) clinical outcomes compared with single-vessel stenting. Thus, stents may be a viable therapeutic strategy in carefully selected patients with multivessel coronary disease.     

Ultrasound coronary angioplasty: state of the art and new clinical aspects

Therapeutic ultrasound was shown to ablate thrombi and to disrupt atherosclerotic plaques in vitro and recently to recanalize occluded coronary arteries in acute myocardial infarction (AMI). The goal of this article is to update collective experience and to weigh the promising and unresolved aspects of this newly developed technology and its clinical results. As therapeutic ultrasound was for long known a synonym for lithotripsy of calculi diseases, it lastly received high attention as a catheter-based ultrasound method to ablate thrombi and disrupt atherosclerotic plaques in interventional cardiology (Figure 1). The effect of therapeutic ultrasound to ablate selectively pathological tissue depends on its bioselectivity for elastic fibers: After ultrasound sonication, healthy tissue-rich in elastin and collagen-including arterial wall remains intact whereas thrombus and plaque with their minimal elastic support are found to be highly susceptible to ablation. Our catheter for coronary ultrasound thrombolysis (Figure 2) consists of a solid metal probe and is connected to a piezo-electric transducer at its proximal end. The distal part ends in a three-wire flexible segment with a 1.6 mm tip ball to guarantee maximal wire flexibility and optimal transmission of ultrasound energy. The initial in vitro studies resulted in a fundamental understanding of the destructive effect of ultrasound on tissue based on 4 factors: mechanical vibration, thermal effects, microcurrents, and cavitation. The first studies on human peripheral vessels were published in 1991 being performed during femoral bypass surgery on occluded and partially obstructed arteries. The procedure was performed without perforation, no adverse side effects emerged, restenosis rate was 20%. The clinical application of coronary ultrasound angioplasty was initiated in 1991; Siegel published his data on 44 patients. In his study, 30 patients with chronic atherosclerotic occlusive lesions and 14 with unstable or stable angina or AMI were treated by ultrasound angioplasty. Residual stenosis after ultrasound treatment was 71%, after balloon dilation reduced to 34%. In the 6-month follow-up angiograms showed no major adverse effect or restenosis. Our experience with coronary ultrasound thrombolysis (CUT) is based on the analysis of 33 patients' data in the feasibility (Table 1) plus multicenter phase of the ACUTE trial (Analysis of Coronary Ultrasound Thrombolysis Endpoints) (Figure 3). Our patients were exclusively treated for AMI by ultrasound angioplasty and afterwards by PTCA if required (Figure 4). The average final percent stenosis was 20% (Figure 5). The main efficacy parameters, device success and angiographic success rates were 100%, clinical success rate was 91.7% (Figure 6 and Table 2). The adverse clinical events of CUT are limited--at least in our studies--to reocclusion of infarct-related artery and ischemia and could be reversed by additional PTCA. No adverse clinical side effects were observed during sonication of the coronary tree. Final angiography revealed residual stenosis of 20% without morphological signs. These excellent results suggest that bioselectivity of ultrasound together with the developed skills of the catheter system induces rapid and selective thrombolysis with no need to cross the target lesion before sonication. But what is the better solution for thrombosis and which for plaque disruption? The development of transluminal balloon catheter really modified therapeutic approach to obstructive coronary and peripheral arterial disease but it is still accompanied by a high rate of abrupt closure, AMI and death. Although the use of intravenous thrombolytic agents is well established in the treatment of AMI and these agents are widely used, a large patient collective remains (up to 33% and more) in whom their use is inadvisable due to recent stroke, surgery, trauma or other contraindications. (ABSTRACT TRUNCATED)     

Estrogen withdrawal-induced human breast cancer tumour regression in nude mice is prevented by Bcl-2

The purpose of this study was to assess the safety and efficacy of percutaneous transluminal cerebral balloon angioplasty (PTCBA) of extra- and intra-cranial arteries by investigating procedural outcome. Eighty haemodynamically significant extra- and intra-cranial lesions (% diameter stenosis > 70) in 74 clinically symptomatic patients were treated by elective and initial PTCBA between March 1991 and February 1996 and thereafter followed. Death, stroke, surgery, or repeated angioplasty of restenosis or new lesions were regarded as cerebral events after the initial PTCBA. The procedural and clinical success rates were 81 % (65 of 80) and 81 % (60 of 74), respectively. Progressively ischaemic symptoms disappeared completely after clinically successful dilatation. Angiographic restenosis rate at 3 months was 22 %(14 of 65). By life-table method, the death/stroke risk was 16 %, and any cerebral event risk was 49 % at 2 years following PTCBA, respectively. The most common of first cerebral events presented was repeated angioplasty of restenosis. In conclusion, PTCBA has great efficacy in decreasing recurrent neurological symptoms and produces a favourable short-term outcome, whereas restenosis limits long-term benefit.