Usefulness of percutaneous transluminal coronary angioplasty in silent myocardial ischemia

The usefulness of percutaneous transluminal coronary angioplasty (PTCA) was assessed in patients with exercise-induced asymptomatic myocardial ischemia (silent ischemia) and compared with exercise-induced symptomatic myocardial ischemia (symptomatic ischemia). Patients with single vessel coronary artery disease (51 with angina pectoris, 40 with old myocardial infarction) and evidence of stress-induced ischemia on thallium-201 single photon emission computed tomography (SPECT) underwent successful PTCA. Thirty-seven percent of angina patients and 60% of infarction patients showed asymptomatic exercise-induced ischemia. There was no significant difference in population characteristics between silent and symptomatic patients. Patients with silent angina had significantly higher percentage thallium uptake and washout rate than symptomatic patients. After PTCA, both percentage diameter stenosis and percentage thallium uptake were improved in all patients with angina irrespective of the presence or absence of symptoms. There were no significant differences in percentage thallium uptake and washout rate between patients with silent and symptomatic infarction. After PTCA, percentage diameter stenosis, percentage thallium uptake, and washout rate improved in all infarction patients irrespective of the symptoms. Zero percent of silent angina patients, 12% of symptomatic angina patients, 12% of silent infarction patients, 19% of symptomatic infarction patients had cardiac events during about 4.5 years after PTCA. The incidence of cardiac events did not significantly differ in any patient group. PTCA improved myocardial perfusion in all patients, and the incidence of cardiac events did not differ between the silent and symptomatic groups. Revascularization with PTCA is suitable for patients with silent as well as symptomatic ischemia.     

The appropriateness of use of percutaneous transluminal coronary angioplasty in New York State

Between 1974 and 1989 we prospectively observed 530 patients with brucellosis. The findings for 62 patients (42 males and 20 females; mean age, 34.7 years) with 63 episodes in which the sacroiliac joint was involved (the most frequent osteoarticular location [11.7%]) were analyzed. Ten of the older patients (mean age, 55.3 years) had concomitant spondylitis. Systemic symptoms were usually important, and characteristic pain and findings of sacroiliitis were observed in approximately 75% of cases. Blood cultures were positive for Brucella melitensis for 44 patients. The most frequent radiographic findings were blurring of articular margins (42 cases) and widening of the sacroiliac space (20 cases). No radiographic anomalies were detected in 13 cases. Results of 99mTc and gallium-67 bone scans were abnormal in approximately 90% of cases (abnormalities were often mild). Overall, clinical, radiographic, and isotopic bone scan findings were sensitive and useful, although they were occasionally minimal or difficult to evaluate, making diagnostic findings confusing or misleading. Brucellar sacroiliitis is a mild disease associated with a good outcome similar to that observed for patients with uncomplicated brucellosis.     

Silent myocardial ischemia in Kawasaki disease: evaluation of percutaneous transluminal coronary angioplasty by dobutamine stress testing

BACKGROUND: Myocardial ischemia and myocardial infarction are the most serious complications of coronary artery lesions in children with Kawasaki disease (KD). Therefore, early detection and treatment of myocardial ischemia in patients with KD is essential. We studied the effectiveness of percutaneous transluminal coronary angioplasty (PTCA) in patients with silent myocardial ischemia detected by dobutamine stress 99mTc myocardial scintigraphy (TMS), body surface mapping (BMS), and signal-averaged ECG late potentials (ELP). METHODS AND RESULTS: Eight of 76 asymptomatic patients with a coronary stenosis >25% and a positive dobutamine stress test were considered to have silent myocardial ischemia. All eight patients had >95% stenoses demonstrated by coronary angiography (CAG) just before PTCA. After PTCA, CAG showed that all of the coronary artery stenoses had been reduced to <50%. Additionally, intravascular ultrasonography (IVUS) performed in five patients before and after PTCA demonstrated adequate dilation of the coronary stenosis after PTCA. All eight patients underwent dobutamine stress TMS, BMS, and ELP 2 to 3 months after PTCA, which demonstrated no regions of myocardial ischemia. Approximately 6 months later, CAG was performed in all eight patients, and only one patient had developed restenosis. CONCLUSIONS: PTCA effectively dilates stenotic coronary arteries in children with KD. Moreover, dobutamine stress TMS, BMS, and ELP are useful for detecting silent myocardial ischemia and estimating the effectiveness of PTCA. Furthermore, IVUS is useful for evaluating the severity of coronary artery lesions before and after PTCA in patients with KD.     

Hemodynamic evaluation of the effect of percutaneous transluminal angioplasty for atherosclerotic disease of the vertebrobasilar arterial system

The relationship between clinical improvement after percutaneous transluminal angioplasty (PTA) and hemodynamic condition in vertebrobasilar insufficiency was evaluated in 43 patients between 45 and 86 years of age with clinically symptomatic atherosclerotic stenotic lesions in the posterior circulation. The 43 patients had a total of 51 stenotic lesions, including 17 in the first segment of the vertebral artery, 32 in the fourth segment of the vertebral artery, and two in the basilar artery. Angiography was performed and cerebral perfusion was measured with technetium-99m-hexamethyl-propyleneamine oxime single photon emission computed tomography before and after administration of 10 mg/kg acetazolamide prior to and more than 7 months after PTA. Mean stenosis was 81.3 +/- 7.4% before PTA, but only 41.5 +/- 17.4% at follow-up. Eighteen of the 24 patients with improved neurological condition after PTA had subnormal (< mean - 2 SDs) cerebral perfusion before PTA. Twenty of these 24 patients had subnormal vasodilatory response to administration of acetazolamide before PTA. Clinical improvement following PTA was noted in only one of the 12 patients with a single stenotic lesion of the first segment, but in 23 of the 31 patients with intracranial stenotic or multiple stenotic lesions. PTA in the posterior circulation is indicated for patients with atherosclerotic stenotic intracranial lesion or multiple stenotic lesions who have subnormal cerebral perfusion and low vasodilatory response to administration of acetazolamide.     

Thrombolysis and angioplasty for acute lower limb ischemia in Buerger''s disease

In the case reported, herpes virus I after having caused relapsing keratitis in an eye promoted the formation of a severe corneal ulcer caused by Scopulariopsis brevicaulis, a saprophytic mycete found in soil, which only once has been described as the cause of keratitis in man. Scopulariopsis was identified microscopically after culturing the conjunctival secretion on Sabouraud dextrose agar medium, while DNA probe tests confirmed the absence of herpes virus I. Topical and oral administration of miconazole and scraping of the corneal infiltrate dispersed the infection. Subsequently local steroids were given to reduce the neovascularization, and a therapeutic contact lens was applied because of intercurrent corneal thinning. Three months after beginning antifungal therapy, the visual acuity had increased from 1/120 to 1/10. The case described confirms that S. brevicaulis can cause opportunist infections in a cornea previously damaged by a different agent.     

Colour flow duplex imaging of occlusive arterial disease of the lower limb

BACKGROUND: The development of duplex ultrasonography and colour flow imaging has greatly extended the scope of non-invasive assessment of lower limb arterial disease. This review questions whether recent advances might allow colour duplex imaging to displace arteriography as the primary imaging modality for native vessel occlusive disease. METHODS: A literature review was carried out based predominantly on a Medline database search of English language publications from 1985 to 1996. RESULTS: Increasing evidence indicates that colour duplex ultrasonography can accurately image the lower limb native arterial tree, and that colour duplex imaging can replace diagnostic arteriography in a large proportion of patients. CONCLUSION: Arteriography should no longer be considered the gold standard of imaging of peripheral arterial occlusive disease. Future studies should concentrate on the efficacy of colour duplex sonography in guiding clinical decision making.     

Pathophysiology of restenosis following percutaneous transluminal coronary angioplasty

Symptomatic restenosis occurs in approximately 30-40% of patients after percutaneous transluminal coronary angioplasty (PTCA). Despite intensive research, the primary pathophysiological mediators have not been defined, and pharmacological therapy has not been effective in preventing restenosis. Restenosis is a multifactorial and sequential process, which is initiated by mechanical injury of the vessel wall, and involves neointima formation caused by the local proliferation of smooth muscle cells and production of an extracellular matrix, followed by vascular remodelling. Numerous mediators are involved in these processes, e.g., protooncogenes, growth factors, cytokines and nitric oxide. This review discusses the pathobiological mechanisms underlying coronary restenosis, and outlines the prospects for future therapy.     

MR angiography of patients with peripheral arterial disease before and after transluminal angioplasty

The strength of the cytotoxic T lymphocyte (CTL) response is believed to influence the final outcome of hepatitis B virus (HBV) infection. Among the different CTL epitopes so far identified, the sequence 18-27 of the HBV nucleocapsid antigen is widely recognized by CTL of HLA-A2-positive patients with acute self-limited HBV infection, and represents the main component of a peptide-based therapeutic vaccine aimed at stimulating the antiviral CTL response in patients with chronic hepatitis B. In the present study, we further analyzed the features of this important HBV region by the following: 1) defining the contribution of individual residues of the epitope to the interaction with the T-cell receptor (TCR) and with the HLA-A0201 molecule; 2) assessing the antigenicity of this viral region in the context of the different HLA-A2 subtypes; and 3) testing whether this sequence can stimulate not only HLA-class I but also HLA class II restricted T-cell responses. A clear hierarchy was observed in the ability of individual residues to act as TCR or HLA binding sites. Furthermore, the sequence HBc18-27 was able to be recognized by specific CTL when presented in the context of different HLA-A2 subtypes. Finally, this HBV region was also found to stimulate HLA class II restricted T-cell responses. These data further increase the potential coverage and efficacy of therapeutic vaccines based on the HBc18-27 sequence.     

Quality of life following percutaneous transluminal angioplasty for claudication

Basal cell carcinoma (BCC) is the most common type of skin cancer and the incidence of BCC is expected to rise, with increased demand on dermatology resources. Little is known of the effect on people's lives of having skin cancer. The aim of this study was to quantify the handicap caused gy basal cell carcinomas before and after therapy. Forty-four patients (22 males, mean age = 65 yrs, range = 35-81 yrs) with 48 BCCs were recruited and 37 patients completed the study. Each patient completed the UK Sickness Impact Profile (UKSIP) and the Dermatology Life Quality Index (DLQI) at the initial visit to the dermatology clinic, 1 week after treatment and 3 months after treatment. Lesions had been present for a mean of 25 months (range = 1-240 months), their mean diameter was 9.6mm (range = 3-35mm) and the sites were head and neck (79%), trunk (17%) and limbs (4%). There was no relationship between the quality of life score and size of lesion. Overall the scores at presentation were very low, rising 1 week after treatment and falling to below the initial scores at 3 months (mean UKSIP 0.4%, 0.7%, 0.13%; mean DLQI 5.3% 8.7%, 1.2%). BCCs cause little handicap. This may explain the delay in seeking medical attention and should be considered in planning public health education about BCCs.     

Management of intracoronary thrombosis complicating percutaneous transluminal coronary angioplasty

With technological advances in equipment and increased experience of operators, the success rates of percutaneous transluminal coronary angioplasty (PTCA) now exceed 90%. However, acute periprocural occlusion continues to complicate approximately 6% of all procedures, and many of these occlusions are due to intracoronary (IC) thrombus. Patients at highest risk for this complication include those with acute ischemic syndromes or with angiographically apparent thrombus. These individuals may be candidates for the use of prolonged heparin infusions prior to dilatation, intracoronary thrombolytic therapy, or monoclonal antibody directed against the platelet glycoprotein IIb/IIIa receptor. All patients undergoing PTCA should receive adequate antiplatelet therapy, including aspirin, and heparin with dosing monitored by activated clotting times (ACT). In addition, some recommend the use of ionic contrast material. When IC thrombus accumulates following intervention, initial therapy should include IC nitroglycerin followed by a combination of redilatation and IC urokinase infusion. Prolonged balloon inflations may be useful, particularly with the use of autoperfusion catheters. Platelet glycoprotein IIb/IIIa receptor antagonists may prove to be beneficial in this situation as well. If the patient's clinical status deteriorates in spite of these measures, emergency coronary artery bypass graft surgery may be required.     

5 years'' experience in complex percutaneous transluminal coronary angioplasty]

SETTING: A residential program in Barcelona for drug addicts (therapeutic community) admitted between November 1988 and March 1992, and followed until September 1994. OBJECTIVE: To study the incidence of tuberculosis as related to the presence of tuberculosis infection and/or human immunodeficiency virus (HIV) infection, and to evaluate the protective effect of chemoprophylaxis with isoniazid. DESIGN: Prospective cohort study. Incidence rates were compared using the Chi-square test for cohort studies. The effectiveness of chemoprophylaxis was evaluated by the Kaplan-Meier method at the univariate level, and by logistic regression models and proportional risks analysis at the multivariate level. RESULTS: During the study of 361 individuals without previous known tuberculosis or history of anti-tuberculosis chemoprophylaxis, 25 developed tuberculosis, an overall incidence rate of 1.79/100 person-years. For HIV-positive persons, the incidence rate was 3.25/100 person-years, compared with 0.30/100 in those who were HIV-negative (P < 0.05). The highest incidence rates occurred among HIV-positive persons who did not receive chemoprophylaxis and who were either anergic (HIV-positive, purified protein derivative [PPD]-negative, Multitest-negative) or who were infected with Mycobacterium tuberculosis (PPD+), 10.0/100 person-years and 4.64/100 person-years, respectively. Of the 53 persons who received chemoprophylaxis, three developed tuberculosis, an incidence rate of 1.4/100 person-years. In comparison, in the group of 51 patients who were designated to receive chemoprophylaxis but where none was actually taken, 17 developed tuberculosis, an incidence rate of 5.7/100 person-years (P = 0.03). CONCLUSION: HIV-infected intravenous drug users, particularly those who are anergic or who are PPD positive, are at increased risk of developing tuberculosis. Anti-tuberculosis chemoprophylaxis proved effective in this population.     

Long-term prognosis of percutaneous transluminal coronary angioplasty in 229 cases]

In order to approach long-term efficacy of percutaneous transluminal coronary angioplasty (PTCA) and the factors affecting its efficacy in Chinese patients, 229 patients who underwent successful PTCA in this institution were followed by direct interview or letters. The rate of follow-up was 95% for the patients who should be followed. The period of follow-up was 0.5-8.4 (mean 2.3 +/- 1.8) years. Angina pectoris recurred in 76 (33.2%) of the patients. In 76% of the patients with recurrence, angina developed within 6 months after PTCA. Cox regression analysis revealed that the relative risk of recurrence of angina pectoris was increased among the patients with triple vessel disease and hypertension. During the period of follow-up, 2 (0.9%) patients died, 6 (2.6%) had non-fatal acute myocardial infarction, 4 (1.7%) had coronary artery bypass graft surgery, and 29 (12.7%) had repeat PTCA. The cardiac event free survival rate calculated by Kaplan-Meier method was 84.8% at 1 year and 70.5% at 8 years. Cox regression analysis revealed that there were positive correlations between stenosis of lesions before PTCA and residual stenosis of LAD after PTCA and the relative risks of cardiac events. In conclusion, the long-term efficacy of PTCA in Chinese patients was good. We suggest that to decrease the residual stenosis of LAD during procedure could probably decrease the relative risk of cardiac events during follow-up.     

Prevention and treatment of restenosis after percutaneous transluminal coronary angioplasty

Restenosis is a clinical problem after coronary angioplasty associated with major ischemic events or repeat interventions in 20-50% of the patients undergoing this procedure. Major efforts have been undertaken in the past decade to successfully prevent or treat restenosis but no pharmacologic approach to the problem has as yet been identified to be effective enough in clinical conditions. New strategies to cope with restenosis are targeted by local application of ionizing radiation which markedly reduces cell proliferation after angioplasty in animal experiments. Preliminary clinical trials indicate that endovascular radiation therapy is a safe and effective means to treat restenosis. Randomized, multicenter studies with long follow-up periods are needed to support these early results.     

Outcome of percutaneous transluminal coronary angioplasty in patients with subclinical hypothyroidism

Recent advances in bone research have employed novel cell and molecular biology techniques to determine some of the fundamental mechanisms regulating bone function. Endocrine control of bone cell development and matrix turnover have been defined at a molecular level by studying the interaction of steroid/thyroid hormones with gene promoters. New steroid/thyroid hormone receptors have been cloned, suggesting that our current view of hormonal regulation of bone metabolism is far from complete. The function of one particular steroid hormone receptor, the vitamin D receptor, has come under close scrutiny following the observation that polymorphic variations in this receptor are linked to differences in bone mineral density. Detailed studies of bone cell differentiation have shown that cytokines may be particularly important targets for hormonal control in bone. The role of cell adhesion molecules in regulating bone resorption has also been explored; modulation of their activity may be of benefit in the treatment of diseases such as osteoporosis. Pharmacological intervention via the newly cloned calcium-sensing receptor offers another site for regulation of bone turnover.     

The challenge and importance of defining critical limb ischemia

Thrombolytic therapy (TT) modifies the natural history of acute myocardial infarction (AMI) diminishing morbi-mortality rate. In recent studies, modification of infusion velocity, decreased the mortality 10 percentage points. OBJECTIVE: Test if rt PA administration over an hour is safe and practical. MATERIAL AND METHODS: A prospective, cooperative trial during 3 years, included patients with AMI with less than 6 hours of the onset of symptoms that received rt-PA therapy. Initially 10 mg bolus and then 90 mg over 60 minutes period. Together with the administration of rt-PA, 5000 units of heparin was given, followed by 1000 units per hour adjusted to keep PTT at 1.5 to 2 times normal. All patients received aspirin and according of the evolution adjuvant therapy. We defined bleeding complications and/or cerebrovascular accident related to thrombolytic therapy. RESULTS: We included 225 patients who received rt-PA. Average age was 57.1 +/- 22.2 years, 78.7% males and 21.3% females. Arrival time at hospital was 2.93 +/- 1.7 hours. 82.2% were in class I-II by NYHA. 59.2% had anterior wall location and 32.4% posterior-inferior wall 80% had reperfusion criteria. Only 7.1% required transfusion and 0.4% presented CNS bleeding. The survival rate was 95.2%. The mortality had no relation with bleeding. CONCLUSION: Fast infusion is an effective and safe method. Transfusion requirements are no greater, and CNS bleeding was noted in 0.4% of the cases.     

The vascular laboratory: a critical component required for successful management of peripheral arterial occlusive disease

Carotid artery dissection is a major cause of cerebral infarction in the young. The extracranial portion of the internal carotid artery is much more frequently involved than the intracranial portion. In up to 20% of cases it is bilateral or associated with vertebral artery dissection. It is mainly characterised by local signs such as headache or facial pain, Horner's syndrome, lower cranial nerve palsies and pulsatile tinnitus, followed a few hours or days later by signs of cerebral or retinal ischemia. Ultrasound investigations show signs of distal stenosis or occlusion, highly suggestive of dissection, but the best diagnostic tool is presently the association of magnetic resonance imaging (MRI) and MR angiography which tend to replace intra-arterial angiography. The prognosis is highly variable: excellent in cases limited to local signs, but very poor leading to death or major sequelae in about 15% of cases. Various treatments have been suggested but no controlled trial has ever been performed in this condition. Heparin in the acute stage followed by warfarin or aspirin for 3 to 6 months is most commonly used.