Emergency percutaneous transluminal coronary angioplasty in acute myocardial infarction: a 3 year experience.

In 151 patients experiencing acute myocardial infarction, emergency coronary angioplasty was performed as primary therapy. Overall, angioplasty was successful in 132 patients (87%); it was successful in 91 (85%) of 107 patients with a totally occluded infarct-related artery and in 41 (93%) of 44 patients with a subtotally occluded infarct-related artery. After successful angioplasty, mean residual stenosis was 29% (range 0 to 70). Eighteen patients were in cardiogenic shock (12%) including four patients receiving cardiopulmonary resuscitation during the angioplasty procedure. Hospital mortality was 9%, with 7 of 13 deaths occurring in patients presenting with cardiogenic shock or intractable ventricular arrhythmia. Hospital mortality was 5% in patients with successful angioplasty versus 37% in those with unsuccessful angioplasty (p less than 0.001). In the immediate period after angioplasty, left ventricular ejection fraction was significantly lower for patients with lesions of the left anterior descending artery (34 +/- 10%) than for patients with lesions of the left circumflex or right coronary artery (43 +/- 11%). In patients with successful angioplasty, significant improvement in left ventricular ejection fraction averaged 13 +/- 12% (p less than 0.001) for those with lesions of the left anterior descending artery and 10 +/- 12% (p less than 0.001) for those with lesions of the left circumflex or right coronary artery. Repeat coronary angiography was performed in 85 (70%) of 121 patients who had successful angioplasty and survived hospitalization without requiring bypass surgery; restenosis was found in 26 (31%), and angioplasty was repeated in 22 patients, successfully in each.(ABSTRACT TRUNCATED AT 250 WORDS)

Status of the myocardium and infarct-related coronary artery in 19 necropsy patients with acute recanalization using pharmacologic (streptokinase, r-tissue plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty) or combined types of reperfusion therapy.

In acute myocardial infarction, myocardial salvage is dependent on rapid restoration of blood flow. Pharmacologic (streptokinase, recombinant tissue-type plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty, guide wire perforation) or combined forms of reperfusion therapy can accomplish this goal, but their effects on infarcted myocardium and vessel occlusion site have not been compared at necropsy. The heart of 19 necropsy patients who had received various forms of acute reperfusion therapy was studied: 14 had pharmacologic or combined forms of reperfusion therapy (13 streptokinase and 1 tissue-type plasminogen activator, including 4 with combined balloon angioplasty) and 5 had had purely mechanical (balloon angioplasty) reperfusion therapy. Reperfusion was initially clinically successful in all 19 patients with the average time from onset of symptoms to reperfusion being 3.7 hours. Necropsy observations separated the 19 patients into distinct subgroups based on changes in the myocardium and infarct-related coronary arteries. Of the 19 patients, 14 (74%) had hemorrhagic myocardial infarction and they all received pharmacologic or combined forms of reperfusion therapy. The remaining five patients (26%) had nonhemorrhagic (anemic) infarction and were treated with balloon angioplasty therapy alone. Increased luminal cross-sectional area was present in 8 of 9 patients with acute balloon angioplasty but severe coronary atherosclerotic plaque remained in 9 of 10 patients without acute balloon angioplasty. Severe hemorrhage surrounded angioplasty sites in all four patients who also received streptokinase or tissue-type plasminogen activator. Severe bleeding at the angioplasty site compromised the dilated coronary lumen in one patient. No patient with angioplasty alone had intraplaque bleeding. Thus, acute coronary balloon angioplasty reperfusion therapy alone appears to avoid the potentially adverse effects of myocardial and intraplaque hemorrhage while simultaneously increasing luminal cross-sectional area at the site of acute occlusion.

Morphologic observations after percutaneous transluminal balloon angioplasty of early and late aortocoronary saphenous vein bypass grafts.

Clinical and morphologic observations from two patients undergoing percutaneous transluminal angioplasty of stenotic aortocoronary saphenous vein bypass grafts early (3 months) and late (56 months) after graft insertion are described. Each patient had one or more clinically successful graft dilations resulting in an angiographic increase in luminal diameter and a decrease in mean trans-stenotic gradient, and each had restenosis of the graft at the site of previous angioplasty within 2 months of dilation. Both operatively excised grafts had diffuse but variable amounts of intimal fibrous thickening and severe narrowing at the previous angioplasty site. The early graft had no evidence of dilation injury, and the intimal thickening consisted solely of fibrocollagenous tissue free of calcific deposits. In contrast, the late graft had a healing intimal dissection at the angioplasty site, and the intimal thickening consisted of atherosclerotic plaque with calcific deposits. Angiographic and morphologic correlations suggest that the mechanism of saphenous vein angioplasty early (less than or equal to 1 year) after insertion is by graft "stretching," while late (greater than 1 year) after insertion it is by atherosclerotic plaque "fracture" similar to that observed in atherosclerotic coronary arteries subjected to angioplasty procedures.

Quantitative coronary angiographic and intravascular ultrasound assessment of a new nonarticulated stent: report from the Advanced Cardiovascular Systems MultiLink stent pilot study.

OBJECTIVES: The purpose of this study was to evaluate the safety, feasibility, optimal deployment technique and 1-year clinical outcome for the Advanced Cardiovascular Systems (ACS) MultiLink stent. BACKGROUND: Optimal stent deployment assessed by quantitative coronary angiography and intravascular ultrasound (IVUS) is associated with improved clinical outcome. METHODS: Forty-nine consecutive patients with a discrete stenosis in a native coronary artery 3 to 4 mm in diameter were treated with the new, balloon-expandable ACS MultiLink stent. Stent expansion was assessed in all patients using quantitative coronary angiography and serial IVUS imaging after 8-, 12- and 16-atm inflations. Clinical follow-up was obtained at 30 days and 1 year. RESULTS: All 49 patients had successful placement of a MultiLink stent without death, emergency coronary artery bypass graft surgery or Q wave myocardial infarction. After placement of the MultiLink stent, the minimal lumen diameter increased from 1.24 to 2.98 mm (p < 0.001), and diameter stenosis decreased from 61% to 7% (p = 0.001). Minimal lumen cross-sectional area by IVUS increased progressively after 8, 12 and 16 atm (5.6 to 6.8 to 7.4 mm2, respectively, p < 0.001). However, only 64% of stents achieved a lumen/reference area ratio > or = 70%. No adverse clinical events occurred by 30 days, and by 1 year only one patient (2.0%) required revascularization of the stented artery. CONCLUSIONS: Treatment of stenoses in native coronary arteries with the MultiLink stent is associated with a high success rate and a low incidence of adverse events by 1 year, despite the fact that the majority of stents did not meet IVUS-defined criteria for "optimal stenting" derived from first-generation devices.

Fatal neutropenia and thrombocytopenia associated with ticlopidine after stenting.

We report 3 cases of fatal neutropenia and thrombocytopenia associated with ticlopidine after coronary stenting. Patients should be counseled about the early signs of infection and bleeding and to have regularly scheduled complete blood counts.

Analysis of the relation between stent implantation pressure and expansion. Optimal Stent Implantation (OSTI) Investigators.

Palmaz-Schatz stents were implanted in 79 lesions in 76 patients, and serially expanded at 12, 15, and 18 atm of pressure using noncompliant balloons. By core lab analysis, intravascular ultrasound demonstrated marked stent expansion as pressure was raised, which was not apparent by angiography.

Hemodynamic effects of lisinopril after long-term administration in congestive heart failure.

To determine whether acute effects of the angiotensin converting enzyme inhibitor lisinopril are maintained during long-term therapy, 19 patients were studied using right-sided heart catheterization before an initial randomized dose of lisinopril and again after 12 weeks of maintenance lisinopril therapy. During initial evaluation, lisinopril produced significant decreases in mean systemic arterial pressure, pulmonary artery wedge pressure, systemic vascular resistance, mean pulmonary arterial pressure, mean right atrial pressure and pulmonary vascular resistance, and concomitant increases in cardiac index and stroke volume index. After 12 weeks of therapy with lisinopril, the dosage of which was titrated to produce optimal relief of symptoms of congestive heart failure (CHF), repeat hemodynamic studies revealed persistent significant reductions in baseline systemic arterial pressure, pulmonary artery wedge pressure, mean pulmonary arterial pressure and systemic vascular resistance. However, the increases in cardiac index and stroke volume index were not statistically significant. To determine if further acute hemodynamic changes occur during long-term therapy, the patients were readministered a dose of lisinopril. This caused further decreases in systemic arterial pressure, mean pulmonary arterial pressure, pulmonary artery wedge pressure, systemic vascular resistance and mean right atrial pressure, and an increase in cardiac index. Lisinopril did not change stroke work index at either initial or rechallenge study. This study indicates that in patients with CHF treated with lisinopril, acute hemodynamic effects persist after 12 weeks of therapy, and acute hemodynamic response continues to occur upon drug readministration.

Usefulness of stent length in predicting in-stent restenosis (the MULTI-LINK stent trials).

The cumulative experience of 4 clinical trials using the MULTI-LINK coronary stent design was analyzed. Multivariable logistic regression identified postprocedure in-stent minimum lumen diameter (p = 0.0001), stent length (p = 0.0038), smoking (p = 0.0105). and diabetes (p = 0.0803) as the most important predictors of in-stent restenosis at late (6- to 9-month) angiographic follow-up.

Final results of a randomized trial comparing the MULTI-LINK stent with the Palmaz-Schatz stent for narrowings in native coronary arteries.

The MULTI-LINK (ML) stent is a novel second generation coronary stent. The ACS MultiLink Stent Clinical Equivalence in De Novo Lesions Trial (ASCENT) randomized 1,040 patients with single, de novo native vessel lesions to treatment with the ML stent or the benchmark Palmaz-Schatz (PS) stent, to demonstrate that the ML stent was not inferior to (i.e., equivalent or better than) the PS stent in terms of target vessel failure by 9 months. Successful stent delivery was achieved in 98.8% versus 96.9% of patients, with a slightly lower postprocedural diameter stenosis (8% vs 10%, p = 0.04), and no difference in 30-day major adverse cardiac events (5.0% vs 6.5%) for the ML stent versus the PS stent. The primary end point of target vessel failure at 9 months was seen in 15.1% of ML-treated patients versus 16.7% of PS-treated patients, with the ML proving to be equal or superior to the PS stent (p <0.001 by test for equivalency). In a prespecified subset, angiographic restudy showed a nonsignificant trend for reduced ML restenosis (16.0% vs 22.1%). Thus, the ML stent showed excellent deliverability and acute results, with 9-month clinical and 6-month angiographic outcomes that were equivalent or better than the PS stent.

Percutaneous transluminal coronary angioplasty for acute myocardial infarction.

Studies have suggested that intracoronary and intravenous thrombolysis and emergency PTCA result in decreased infarct size, improved left ventricular function, and decreased in-hospital mortality. Significant problems remain with all three treatment modalities. Thrombolysis is associated with significant bleeding, especially if acute catheterization also is performed. The intracoronary method of thrombolysis requires cardiac catheterization facilities and entails a significant delay in reperfusion. Lower rates of reperfusion initially were found with intravenous than intracoronary streptokinase, but the intravenous administration of t-PA has been associated with a reperfusion rate (75 per cent) similar to that of intracoronary streptokinase. Significant bleeding complications occur with t-PA just as with streptokinase. Furthermore, there are patients in whom thrombolysis is contraindicated because of the high risk of life-threatening hemorrhagic complications. Once thrombolysis is achieved, an underlying significant coronary artery lesion usually is present so that a significant risk of recurrent ischemia and/or reinfarction still exists. In controlled studies, the addition of cardiac catheterization and angioplasty after thrombolytic therapy is associated with a further increase in significant bleeding episodes. Also, in low-risk subgroups of patients randomized to emergency angioplasty versus elective angioplasty or noninvasive treatment after thrombolytic therapy, the complications of angioplasty may outweigh the benefits of further reduction in lesion severity. Potential problems of emergency angioplasty following thrombolytic therapy include: (1) hemorrhage into ischemic myocardium, which may have a deleterious effect on ultimate muscle recovery; (2) hemorrhage at the angioplasty site caused by thrombolytic therapy, with a resultant increased chance of occlusion of the vessel post-angioplasty, and (3) production of reperfusion arrhythmias and hypotension, predisposing to vessel reclosure and infarct extension. With primary angioplasty therapy, the reperfusion success rate is 85 to 90 per cent. This is higher than the approximately 75 per cent success rate with thrombolytic therapy alone. If angioplasty can be performed expeditiously, within 6 hours of the onset of ischemia, potential advantages of this technique include: (1) rapid reperfusion, possibly comparable to thrombolytic therapy alone; (2) higher success rate for reperfusion than thrombolytic therapy; (3) alleviation of underlying stenosis usually present after thrombolytic therapy alone; (4) avoidance of systemic thrombolysis, with a concomitant decrease in hemorrhagic risk; (5) possible avoidance of hemorrhagic infarction, which may have a deleterious effect on ultimate muscle recovery; and (6) applicability to patients in cardiogenic shock, who presently respond poorly to thrombolytic therapy alone. No large controlled randomized study exists comparing primary angioplasty with thr

Percutaneous laser-assisted thermal coronary angioplasty in native coronary arteries and saphenous vein grafts: initial results and angiographic follow-up.

Percutaneous laser-assisted thermal coronary angioplasty was attempted in 29 vessels (27 patients): 10 left anterior descending, 2 left circumflex and 17 mid-shaft (non-anastomotic) saphenous vein grafts. Argon or YAG laser thermal energy was applied via a 1.3, 1.6 or 1.9 mm metal capped probe followed by conventional balloon angioplasty in 27 vessels and sole thermal laser therapy in two vessels. The laser probe successfully crossed 83% (24/29) of vessels and subsequent balloon dilatation increased the success rate to 93% (25/27). Perforation occurred in a vein graft resulting in one in-hospital death post repeat emergency coronary artery bypass graft surgery. Angiographic follow-up was obtained in 85% (24/28) of vessels. Angiographic restenosis ( greater than 50% reduction in lumen diameter) occurred in 27% (3/11) of native coronary arteries and 62% (8/13) of saphenous vein grafts. Therefore, despite high initial success rates, the application of laser thermal energy with small laser probes relative to vessel size, followed by conventional balloon angioplasty, does not appear to alter restenosis. Further evaluation of coronary laser systems should be continued only with catheters that are capable of creating channels closer to the size of the vessel treated.

Exercise testing and training of the elderly patient.

As an invariable accompaniment of the aging process, cardiac function declines, that is, cardiac output, stroke volume, heart rate, and maximum oxygen consumption all decrease. The vital capacity declines as residual volume increases, and ventilation-perfusion imbalance increases. Muscles atrophy and weaken, joints stiffen, and bones are demineralized. Certainly the aging process per se explains a portion of this functional deterioration. Disease states also account for some deterioration. However, inasmuch as approximately one half of the deterioration in function can be prevented or reversed by an exercise training program, it would seem that disuse or inactivity is responsible for at least a portion of the functional decline characteristic of aging. Special considerations in prescribing exercise training for the elderly include careful cardiovascular assessment; evaluation of orthopedic problems; consideration of heat intolerance; and careful attention to motivation. The exercise prescription should be specific and tailored to the subject's individual cardiovascular status, musculoskeletal limitations, and personal goals. Walking, stretching calisthenics, and other aerobic activities, if of reasonable intensity and duration, and when preceded and followed by an appropriate warm-up and cool-down period, respectively, can result in a substantial, positive training effect in the elderly. In response to such a training program, elderly subjects demonstrate an increase in stroke volume, cardiac output, and maximum heart rate. Respiratory function changes little, yet maximal oxygen consumption is increased. Fat may be replaced by lean muscle mass as muscle strength and endurance improve. Flexibility is improved and bone demineralization retarded or even reversed. Exercise has a tranquilizing effect on elderly subjects so that anxiety and depression may be prevented. The subject develops self-respect as effort tolerance improves. An excessively conservative attitude on the part of physicians, families, and elderly subjects has resulted in inappropriate activity limitations with a consequent decrement in effort tolerance. Elderly individuals can maintain a reasonable level of effort tolerance or can be rehabilitated to this level of activity with an appropriate exercise program. The decline in overall function expected with age can be substantially retarded. Consequently, physicians, families, and the subjects themselves should consider the potential advantages of an exercise program.

Intravascular ultrasound imaging combined with coronary angioplasty.

A novel catheter combining ultrasound imaging and coronary balloon angioplasty was used in the treatment of 69 coronary-artery lesions in 51 patients. The ultrasound transducer enables real-time cross-sectional imaging and qualitative and quantitative assessment of the vessel wall before and after angioplasty. The combination catheter successfully dilated 67 lesions. There was a characteristic three-layered appearance, representing intima, media, and adventitia, in 60 cases. Intravascular imaging provided information on the vessel wall unobtainable by standard contrast angiography in 28 cases and influenced our management in 6 cases.

Initial clinical experience with a novel low-profile integrated ultrasound-angioplasty catheter.

This report is the first clinical description of the use of a new low-profile integrated ultrasound-angioplasty catheter (the Oracle Micro, Endosonics Corp.), which has recently been approved by the FDA for routine use during percutaneous transluminal coronary angioplasty (PTCA). PTCA was performed in 44 patients at two clinical sites. With this device, PTCA was accomplished in 47 of 55 (85%) lesions ultimately successfully dilated with balloon angioplasty. No major procedural complications occurred. Adequate ultrasound images were obtained in 51 of 57 lesions (89%). Ultrasound imaging revealed significant morphologic information not apparent by angiography in 51% of imaged lesions and altered the dilatation strategy in 33% of cases. In 10 lesions in which greater inflation pressure or balloon upsizing was performed based solely on an inadequate post-PTCA ultrasound appearance, the minimal lumen diameter further increased from 2.3 +/- 0.3 mm to 2.7 +/- 0.5 mm (P < .001), with no dissections or complications. PTCA may be performed safely in the majority of patients currently undergoing balloon angioplasty with a new low-profile integrated ultrasound-angioplasty catheter. Ultrasound imaging during PTCA provides significant information complementary to angiography and may favorably affect the dilatation strategy of experienced operators.

Percutaneous transluminal coronary angioplasty and stenting for cocaine-induced acute myocardial infarction: a case report and review.

Cocaine-induced myocardial infarction has been well reported. Likewise, there are numerous reports of patients with cocaine-induced myocardial infarction being treated conservatively with nitroglycerin, verapamil, and thrombolytics. However, based on a Medline search from 1977 to 1998 (with the keywords cocaine and angioplasty), there have been no reports in English of cocaine-induced myocardial infarction being treated with catheter-based intervention. We report such a case, as well as review what is known about the pathophysiology of cocaine-induced coronary arteriopathy and myocardial infarction.