Determination of renal arterial stenosis severity: comparison of pressure gradient and vessel diameter.

PURPOSE: To determine the hemodynamic significance of arteriographically detected renal arterial stenosis by obtaining pressure gradients with a miniaturized pressure guide wire. MATERIALS AND METHODS: Forty-six renal arterial stenoses in 38 patients were assessed in terms of severity and then subjected to gradient determination before and after angioplasty. The patients (mean age, 63 years) had a mean serum creatinine value of 1.3 mg/dL +/- 0.4 (114.9 micromol/L +/- 35.4 [SD]) and required on average three medications for blood pressure control. The mean degree of stenosis diameter was 51% +/- 17 (range, 12%-85%). RESULTS: The systolic and mean arterial pressure gradients with and those without vasodilatation were highly correlated with stenosis severity, systolic blood pressure, and serum creatinine as a curvilinear fit (r = 0.9, P <.01). At 50% stenosis severity, the mean pressure gradient was 22 mm Hg. CONCLUSION: Patients with a pressure gradient greater than 20 mm Hg should be good candidates for renal arterial dilatation, and use of the pressure guide wire will facilitate interventional decisions.

[Renovascular illness: prevalence and therapy in patients with coronary heart disease]. / Die renovaskuläre Erkrankung: Prävalenz und Therapie bei Patienten mit koronarer Herzerkrankung.

To explore the relationship between coronary artery disease and renal vascular disease, we performed renal arterial angiography in 609 patients undergoing coronary angiography for suspected coronary artery disease. We defined renal artery stenosis as nonsignificant (< 40%), borderline (40-60%) and significant (> 60%). One-hundred fifty-two patients had renal artery stenosis, while 457 did not. Two-hundred and ten patients had no coronary disease; of these, only 9 had renal artery stenosis. On the other hand, the 143 patients with renal artery stenosis, when subdivided, had similar degrees of coronary disease; three vessel disease was significantly more common than one or two vessel disease in all groups. Renal artery stenosis of all severity degrees was associated with common atherosclerotic risk factors. However, hypertension was not a clue to the presence of renal artery stenosis. To evaluate the effect of percutaneous revascularization on hypertension and renal function all 51 patients with significant renal artery stenosis were treated by primary stent implantation and were followed up for 6 months. Stent implantation showed a marked decrease in systolic and diastolic blood pressure (163 +/- 30 to 145 +/- 17 and 93 +/- 18 to 83 +/- 10 mmHg; p = 0.008) with a decrease in the amount of antihypertensive medication but without beneficial effect on serum creatinine during follow-up (1.46 +/- 0.70 mg/dl to 1.39 +/- 0.58 mg/dl, p = ns). We conclude that renal artery stenosis of any severity is strongly suggestive of three vessel coronary artery disease. The fact that renal stenting lowers blood pressure decreases antihypertensive drugs and increases medication flexibility in patients with coronary artery disease would support the notion of revascularization in patients with significant stenoses.

Clinical and angiographic outcome in patients with in-stent restenosis and repeat target lesion revascularisation in small coronary arteries.

OBJECTIVE: To evaluate the clinical and angiographic outcome in patients with in-stent restenosis in small coronary arteries and repeat target lesion revascularisation. DESIGN: Patients with in-stent restenosis in coronary arteries < or = 2.85 mm were eligible for the study and underwent target lesion revascularisation. Clinical and angiographic variables were assessed during a six month follow up period. RESULTS: 73 patients with 79 lesions were treated by percutaneous transluminal coronary angioplasty (47%), excimer laser angioplasty (25%), or restenting (28%). The mean (SD) reference diameter before target lesion revascularisation was 2.12 (0.5) mm. Procedural success was achieved in all cases, but 57% of the patients had restenosis after six months. The rate of further restenosis was higher with laser angioplasty (78%) than with restenting (47%) or balloon angioplasty alone (49%, p < 0.05). CONCLUSIONS: Treatment for in-stent restenosis in small coronary arteries is feasible and safe, with a second restenosis rate comparable to large coronary artery series. The strategy of target lesion revascularisation influences further in-stent restenosis, with an increased rate with laser angioplasty compared with restenting and repeat dilatation alone.

The value of magnetic resonance imaging of the left ventricular outflow tract in patients with hypertrophic obstructive cardiomyopathy after septal artery embolization.

BACKGROUND: We tested the value of magnetic resonance imaging (MRI) in the follow-up of patients with hypertrophic obstructive cardiomyopathy after septal artery embolization. MRI provides a noninvasive visualization of transplanar turbulent flow in order to quantify left ventricular outflow tract obstruction. METHODS AND RESULTS: We followed 10 patients who were treated with septal artery embolization for 12 months. We used gradient echo sequences to document continuous improvement of the outflow tract area and T1- and T2-weighted spin echo sequences to visualize myocardial infarction. A continuous, but not linear, improvement of the outflow tract area occurred after septal artery embolization during the 12-month follow-up period. The improvement of the outflow tract area correlated well with the amelioration of symptoms (r(2)=0.86). CONCLUSIONS: We conclude that MRI reliably detects the degree of obstruction in patients with hypertrophic obstructive cardiomyopathy. This modality may be especially useful for follow-up after septal artery embolization.

Postcatheterization pseudoaneurysms and arteriovenous fistulas: repair with percutaneous implantation of endovascular covered stents.

PURPOSE: To assess the effectiveness and safety of endovascular covered stents in the management of pseudoaneurysms and arteriovenous fistulas after cardiac and vascular catheterization. MATERIALS AND METHODS: Twenty-six endovascular covered stents were used to repair 16 pseudoaneurysms, nine arteriovenous fistulas, and one combined lesion after femoral arterial puncture for diagnostic coronary angiography and/or angioplasty. Fistulas and aneurysms were in the superficial femoral artery in 16 cases, in the deep femoral artery in six cases, and in the common femoral artery in four cases. Implantation was performed from the opposite femoral artery in most cases. It was not possible to treat three additional cases transcutaneously for technical reasons (three of 29 cases). RESULTS: Percutaneous closure of the lesions with an endovascular covered stent was successful in 26 of 29 cases. Initial follow-up showed good stent patency. Two major complications were observed after stent implantation. During follow-up (about 1 year in 23 of 26 patients [88%]), stent thromboses were detected in four of 23 patients (17%) with follow-up color duplex flow imaging. CONCLUSION: Implantation of endovascular covered stents is an effective and safe method for the percutaneous closure of pseudoaneurysms and arteriovenous fistulas. Thus, endoluminal vascular repair with covered stents offers an alternative therapeutic approach to vascular surgery in selected patients.

Percutaneous treatment of pseudoaneurysms and arteriovenous fistulas after invasive vascular procedures.

Development of femoral artery pseudoaneurysms and arteriovenous fistulas represents a continuing problem after vascular diagnostic and interventional procedures. For most patients, ultrasound-guided compression is an effective method of treating such complications. However, in patients requiring a continuous anticoagulant regimen, in those with large arteriovenous fistulas or in patients suffering from painful groin hematomas, compression repair is less successful. We therefore assessed the feasibility, efficacy, and long-term results of interventional percutaneous treatment of these complications. In a 40-month period, we treated 53 consecutive patients with 30 pseudoaneurysms, 21 arteriovenous fistulas, and 2 combined lesions. The intervention was successful in 47 patients: 32 lesions were treated by implantation of covered stents, 14 by embolization techniques, and 1 by a combined procedure, surgical repair being necessary only in 6 patients. After a clinical and ultrasonic follow-up of 301 +/- 280 days, we noticed four late stent occlusions, especially in patients with poor peripheral runoff. Lesions with a distinct connection channel to the vessel lumen should be treated by coil embolization. In lesions originating from the femoral bifurcation with a broad base, surgical repair is necessary. Stenting of the superficial femoral artery with poor runoff should be avoided. Our results suggests that percutaneous closure of false aneurysms and arteriovenous fistulas after invasive procedures with unsuccessful ultrasonic compression repair is an attractive alternative to surgical treatment.

Treatment of carotid artery stenosis by elective stent placement instead of carotid endarterectomy in patients with severe coronary artery disease.

Patients with concomitant cardiac and cerebrovascular disease undergoing revascularization procedures are at high risk of both, cardiac and cerebrovascular complications. The purpose of our study was to evaluate the feasibility of prior elective carotid artery stenting as an alternative treatment procedure to carotid endarterectomy (CEA) in patients with concomitant coronary artery disease (CAD), who clearly needed coronary revascularization. We offered extracranial internal carotid stenting to 85 patients with 89 significant carotid stenoses. Out of these, 19 patients were symptomatic. The quantitative mean reduction in diameter was 77 +/- 11%. Stent implantation was successful in 88 lesions. Two disabling major and 3 reversible minor strokes occurred periprocedurally. Three patients showed asymptomatic restenosis and stent deformation was detected in 2 patients. Based on this experience, carotid stenting in high risk patients with severe coronary artery disease is feasible and safe and might be indicated as an alternative procedure for combined surgery.

Elective stenting of carotid artery stenosis in patients with severe coronary artery disease.

AIMS: To evaluate the feasibility and safety of elective carotid stent implantation in patients with carotid stenoses and concomitant coronary artery disease, as an alternative to combined carotid and coronary surgery. METHODS: We treated 50 patients with >70%, stenoses in 53 carotid arteries with balloon angioplasty followed by elective stent implantation. All patients had severe coronary artery disease, and/or mitral insufficiency, aortic stenosis, rhythm disorders or generalized arteriosclerosis. In three patients the opposite carotid artery was occluded; nine patients had bilateral stenoses of which two received stents bilaterally. RESULTS: Fifty-six successful stent implantations (42 Wallstents, eight BeStents, two AVE-Microstents, one Palmaz Schatz stent, three Sito stents) were performed, reducing the baseline percent stenosis from 78 +/- 18%, to 13 +/- 11%. Complications included three transient ischaemic attacks, one minor and one major stroke. Follow-up was available for 46 patients over a mean of 10 months. Three asymptomatic restenoses and one deformation of a BeStent occurred. CONCLUSION: Our preliminary results indicate that carotid artery stenting in patients with concomitant severe coronary artery disease is feasible, safe, and may be an alternative to combined carotid and coronary surgery.

Ostial renal artery stent placement for atherosclerotic renal artery stenosis in patients with coronary artery disease.

To test the utility of endoprosthetic treatment for ostial renal artery stenosis, and to examine blood pressure and its treatment, serum creatinine, and restenosis rate, 44 ostial renal stent placements were performed in 30 patients with concomitant coronary artery disease, arterial hypertension, and the indication for angiotensin converting enzyme (ACE) therapy. There was a marked decrease in systolic and diastolic blood pressure (163+/-30 to 145+/-17 and 93+/-18 to 83+/-10 mm Hg; P < 0.008) with a decrease in number of medication (3.2+/-0.9 to 2.8+/-1.0; P = 0.005). In 5 out of 8 patients not receiving an ACE inhibitor, this drug could be added. Serum creatinine changed from 1.46+/-0.7 mg/dl to 1.39+/-0.58 mg/dl (P = ns). Three patients showed restenosis (12.5%). Ostial stenting lowers blood pressure, decreases antihypertensive drugs and increases medication flexibility.

Sixty-minute alteplase protocol: a new accelerated recombinant tissue-type plasminogen activator regimen for thrombolysis in acute myocardial infarction.

OBJECTIVES: Our aim was to design and evaluate a new and easily administered recombinant tissue-type plasminogen activator (rt-PA) regimen for thrombolysis in acute myocardial infarction (AMI) based on established pharmacokinetic data that improve the reperfusion success rate. BACKGROUND: Rapid restoration of Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow is a primary predictor of mortality after thrombolysis in AMI. However, TIMI grade 3 patency rates 90 min into thrombolysis of only 50% to 60% indicate an obvious need for improved thrombolytic regimens. METHODS: Pharmacokinetic simulations were performed to design a new rt-PA regimen. We aimed for a plateau tissue-type plasminogen activator (t-PA) plasma level similar to that of the first plateau of the Neuhaus regimen. These aims were achieved with a 20-mg rt-PA intravenous (i.v.) bolus followed by an 80-mg i.v. infusion over 60 min (regimen A). This regimen was tested in a consecutive comparative trial in 80 patients versus 2.25 10(6) IU of streptokinase/60 min (B), and 70 mg (C) or 100 mg (D) of rt-PA over 90 min. Subsequently, a confirmation trial of regimen A in 254 consecutive patients was performed with angiographic assessment by independent investigators of patency at 90 min. RESULTS: The comparative phase of the trial yielded, respectively, TIMI grade 3 and total patency (TIMI grades 2 and 3) of 80% and 85% (regimen A), 35% and 50% (B), 50% and 55% (C) and 60% and 70% (D). In the confirmation phase of the trial, regimen A yielded 81.1% TIMI grade 3 and 87.0% total patency. At follow-up angiography 7 (4.1%) of 169 vessels had reoccluded. In-hospital mortality rate was 1.2%. Nadir levels of fibrinogen, plasminogen and alpha2-antiplasmin were 3.6 +/- 0.8 mg/ml, 60 +/- 21% and 42 +/- 16%, respectively (mean +/- SD). Fifty-seven patients (22.4%) suffered from bleeding; 3.5% needed blood transfusions. CONCLUSIONS: The 60-min alteplase thrombolysis in AMI protocol achieved a TIMI grade 3 patency rate of 81.1% at 90 min with no indication of an increased bleeding hazard; it was associated with a 1.2% overall mortality rate. These results are substantially better than those reported from all currently utilized regimens. Head to head comparison with established thrombolytic regimens in a large-scale randomized trial is warranted.

Stent implantation in patients with superior vena cava syndrome.

OBJECTIVE: The purpose of this study was to determine the feasibility of using Wallstent implantation to treat superior vena cava syndrome due to malignant tumors. SUBJECTS AND METHODS: Digital subtraction angiography showed obstruction of the superior vena cava in 13 patients who then underwent transluminal dilatation and Wallstent implantation. The patients were treated with IV heparin and monitored in the emergency department. Thereafter, they were treated with a platelet inhibitor for 4 weeks. RESULTS: Because their signs and symptoms improved, patients were able to resume radiation therapy, chemotherapy, or both. One patient died of cardiac arrhythmia 1 day after stent placement. Although eight patients have subsequently died of their bronchial or thyroid gland tumors, superior vena cava syndrome did not recur in any patient. CONCLUSION: Percutaneous implantation of Wallstent endoprostheses provides excellent palliation for superior vena cava syndrome.

[Stents: new studies--new trends]. / Stents: Neue Studien--neue Trends.

The increasing frequency of stent implantation into coronary arteries is based mainly on assumptions. One of these assumptions is that stents may prevent restenosis. Stents can prevent restenosis as has been shown in two randomized studies (Stress I and Benestent I), but only in large (> 3.0 mm) vessels with short denovo lesions. Despite the very tight selection of patients suitable for stent implantation in these two studies, the advantage for stents remained small (about 10% less restenosis) and appeared to decrease with time following intervention. There is increasing concern about the extension of stenting in an "unrestricted strategy". This concern was expressed in the ACC Expert Consensus Document which was published recently (JACC 28, No 3, September 1996: 782-794). Based on lack of data for most of the presently used stent indications the expert group recommended a more selective strategy for the implantation of stents into coronary arteries.

[Rare vascular findings in CT of the upper mediastinum]. / Seltene Gefässbefunde im CT des oberen Mediastinums.

The CT findings of malformation of major veins near the heart are described (one case of persistent left superior vena cava and two cases of partial anomalous pulmonary veins) as well as one malformation of the pulmonary artery (vascular sling). These findings demonstrate the vascular character of the lesion and the procedure permits detailed clarification of the abnormality.

[Roentgenologic data patterns and hemodynamics in biopsy-proven dilated myocardial diseases]. / Röntgenologische Befundmuster und Hämodynamik bei bioptisch gesicherten dilatativen Myokarderkrankungen.

The chest plain images of 63 patients suffering from histologically proved dilated myocardial diseases: primary cardiomyopathy (27), active and residual myocarditis (23), toxic cardiomyopathy (3), endomyocardial fibrosis (2), thesaurismotic cardiomyopathy (2), obstructive intramural fine vessel diseases (6) were analysed and correlated with invasively determined parameters: end-diastolic volume index, wall mass index, left ventricular end-diastolic pressure, pulmonary artery mean pressure, ejection fraction. The x-ray findings proved to occur in four different patterns which were defined as left heart involvement and three different patterns of bilateral left and right heart involvement representing various stages of left heart failure. This kind of image evaluation with functional classification is characterized by increased sensitivity, accuracy and information in detail in comparison with the heart lung index or other usual procedures.

[Results of the complex evaluation of scintigraphy of the intracardiac space in patients with coronary disease]. / Ergebnisse der komplexen Auswertung der Herzbinnenraumszintigraphie bei Patienten mit koronarer Herzkrankheit.

With the help of the comparison of the results of 95 patients with coronary heart disease who were examined by means of the intracardiac space scintigraphy for the purpose of the subjective subdivision according to the NYHA-classification there is no close correlation between the nuclear-medically obtained functional sizes (EF, maximum ejection and filling rate) and the clinical degree of severity of the disease. Only at the degree of severity 3 and 4 a discrimination is possible. In 64 patients laevocardiographic and coronarographic, respectively, findings were present. The trend to the deterioration of the functional parameters and to the increase of the nuclear-medically recognizable disturbances of the kinetics, respectively, with a more intensive expression of the vascular stenoses is distinctly readable. From the examination in rest in the individual case no statement is possible concerning the findings which are to be expected in the invasive diagnostics. When there are discrepancies between the result of the intracardiac space scintigraphy and the clinical and electrocardiographic preliminary investigations in many cases a clarification becomes possible by the immediately following study under submaximal exercise. On the assumption of a close cooperation with experienced cardiologists the relatively little expensive intracardiac space scintigraphy which does not stress the patient provides an essential evidence for the prognosis and estimation of the functional capacity of the patients with coronary heart disease.

[Diagnostic contribution of endomyocardial biopsy in suspected latent cardiomyopathy]. / Diagnostischer Beitrag der Endomyokardbiopsie bei Verdacht auf latente Kardiomyopathie.

Twenty-eight patients with suspected diagnosis of latent cardiomyopathy are reported. In all patients left ventricular endomyocardial biopsy (five or more specimens) was performed after noninvasive and invasive investigations. The indication to investigate invasively arose from clinical symptoms in combination with uncertain ECG disturbances. Coronary heart disease, latent myocarditis and latent cardiomyopathy were to be excluded. Hemodynamic parameters proved to be normal or borderline at rest. Angiocardiography and coronary angiography revealed no pathological findings. But in all cases the histological results of endomyocardial biopsy were characterized by pathological criteria as follows: inflammatory myocardial process, narrowing or obliterating diseases of intramural small arteries, exogenous-toxic myocardial disturbances, idiopathic cardiomyopathy, endomyocardial fibrosis with endocardial thrombus and infiltrations of eosinophiles. Four cases are demonstrated as examples.