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S Jost

Publications and source records attributed to S Jost.

At least 37 records · Page 2Linked to original sources
PubMed1996

Association between coronary occlusions and myocardial infarcts. The INTACT investigators. International Nifedipine Trial on Antiatherosclerotic Therapy.

The number of angiographically documented coronary occlusions and the incidence of Q-wave myocardial infarcts were retrospectively compared in 348 patients with moderate coronary artery disease from the INTACT study (International Nifedipine Trial on Antiatherosclerotic Therapy). In only 68 out of 118 infarcts (58%) an occlusion of the respective coronary artery was found, suggesting a spontaneous recanalization rate of 42%. On the other hand, only 68 out of 150 coronary occlusions (45%) had resulted in a Q-wave infarct. Considering the high spontaneous recanalization rate of the occlusions, it seemed possible that roughly only every fourth coronary occlusion might result in a myocardial infarct. This hypothesis was confirmed in the prospective 3 years follow-up of the identical patients during which 41 new occlusions developed causing only 10 myocardial infarcts (24%). These findings might contribute to explain the relatively low incidence of clinically apparent coronary heart disease in the general population despite a high prevalence of coronary artery disease.

Arterial Occlusive Diseases↗
PubMed1996

Standardization of coronary vasomotor tone with intracoronary nitroglycerin.

Maximal, reproducible, and thus "standardized" dilation of epicardial coronary arteries can be easily achieved with intracoronary bolus administration of 0.1 mg nitroglycerin without considerable decrease in blood pressure. The addition of other nitrocompounds or calcium antagonists cannot increase coronary dilation after nitroglycerin, but may be hampered by adverse effects.

Blood Pressure↗
PubMed1996

Comparison of different quantitative coronary analysis systems: ARTREK, CAAS, and CMS.

It has been known that the first generation quantitative coronary analysis systems overestimate small vessel sizes. In the 2nd generation the contour detection algorithms, e.g., of the new Cardiovascular Measurement System (CMS), were modified to correct for the limited resolution of the X-ray imaging chain. This study validated and compared the CMS with the well-known Coronary Angiography Analysis System (CAAS) and the vessel tracking program ARTREK in a phantom study and a clinical study. In addition, the influence of different acquisition media (cinefilm vs. digitally acquired angiograms) on the accuracy of quantitative analysis was examined. The phantom study comprised 19 stenotic or non-stenotic glass tubes with a diameter range from 0.54 mm to 4.9 mm. In the clinical study the mean diameters of 322 coronary segments were analysed and the results of the systems were compared among each other. The results of the phantom study were presented in terms of the mean difference (accuracy) between true and measured values. In the phantom study the overall accuracy of the CMS was -6 microns (ARTREK: 85 microns; CAAS: 35 microns) with an overestimation of small vessels of only -11 microns (ARTREK: 97 microns: CAAS: 51 microns). The clinical study showed that the CMS corrected the usually occurring overestimation of small coronary arteries and that the influence on the accuracy of different acquisition media is minor. Due to the modified algorithms the new CMS is able to measure coronary diameters down to 0.5 mm accurately. Therefore, the CMS seems to provide more precise measurements in quantitative analysis of small coronary diameters than CAAS and ARTREK.

Coronary Angiography↗
PubMed1995

Influence of the selection of angiographic projections on the results of coronary angiographic follow-up trials. International Nifedipine Trial on Antiatherosclerotic Therapy Investigators.

In recent years follow-up trials on coronary artery disease with angiographic end points analyzed quantitatively have gained increasing relevance and popularity. There is no consensus, however, on the method of calculation of progression or regression from multiple angiographic projections. Therefore the influence of the selection of angiographic projections on the outcomes of such trials was investigated with the data of the International Nifedipine Trial on Antiatherosclerotic Therapy. In 348 patients with coronary artery disease, repeated coronary angiograms were compared in multiple identical angiographic projections. Changes in angiographic parameters were averaged over the 1063 stenoses analyzed. Five methods of evaluation of multiple projections in the individual stenoses were applied, resulting in different extents of overall progression, or even regression of coronary artery disease (p < 0.01). It is concluded that in quantitative coronary angiographic follow-up trials changes should be averaged over all angiographic projections available for a stenosis to avoid overestimation of progression or regression.

Analysis of Variance↗
PubMed1995

[Modifying increased plasma cholesterol levels in secondary prevention of coronary heart disease].

In secondary prevention of coronary heart disease, the reduction of elevated cholesterol plasma levels is mainly based on diet and/or drugs. Invasive means such as partial ileal bypass operation or LDL-apheresis, although highly effective in reducing cholesterol levels and incidence of clinical cardiac events, should be reserved for special subgroups of patients. With dietary measures such as strict reduction of calories originating from fat, as well as with increased consumption of fish, fruits, vegetables and cereals, clinical or angiographic benefits could be demonstrated; in addition to the reduction of cholesterol plasma levels, other mechanisms such as inhibition of platelet aggregation and protection of LDL-particles from oxidation may contribute to this effect. With drugs reduction of cardiac events and of cardiac and total mortality was not observed in all clinical studies. Most angiographic drug studies revealed a significant, although quantitatively moderate retardation of the progression of coronary artery disease. However, only in a few studies did the clinical or angiographic effects correlate with the extent of changes in total, LDL- or HDL-cholesterol plasma levels or their absolute values on trial. Women and men seem to benefit equally from drug therapy. The efficiency of cholesterol-lowering measures in patients with age > 70 years is still unknown, however. In patients with coronary artery disease and normal cholesterol plasma levels neither clinical nor angiographic benefits could so far be demonstrated with cholesterol-lowering measures. Thus, to date in the secondary prevention of coronary artery disease cholesterol-lowering therapy with drugs only seems definitely indicated in patients < 70 years of age with hypercholesterolemia resistant to diet.

Adult↗
PubMed1994

Evolution of coronary stenoses is related to baseline severity--a prospective quantitative angiographic analysis in patients with moderate coronary disease. INTACT Investigators. International Nifedipine Trial on Antiatherosclerotic Therapy.

A correlation of the angiographic evolution of coronary stenoses (stenosis diameter > or = 20%) with morphological stenosis parameters at baseline could help to identify the risk of progressive stenoses. Therefore, the data of the prospective INTACT study (International Nifedipine Trial on Antiatherosclerotic Therapy) were reviewed. In 348 patients with moderate coronary artery disease, standardized coronary angiograms were taken 3 years apart and were quantitatively analysed. Changes in the minimal diameter of the 1063 preexisting coronary stenoses compared between both angiograms were set in relation to a number of conventional stenosis parameters at baseline. Regression analysis demonstrated a significant correlation of the changes in minimal diameter with baseline % diameter stenosis (r = 0.30; P < 0.001), minimal diameter (r = -0.28; P < 0.001) and reference diameter of stenoses (r = -0.14; P < 0.001). The changes were not correlated with stenosis length and plaque area. The baseline parameters of 22 preexisting stenoses progressing to occlusions differed from those remaining patent only with regard to the % diameter stenosis (43 +/- 9% vs 39 +/- 11%; P < 0.05). Additional progression of coronary disease became manifest through development of 228 stenoses and 19 occlusions at arterial sites free from definitive stenoses in the baseline angiograms. Thus, progression of atherosclerosis predominantly occurred in mild preexisting coronary stenoses and developed at previously angiographically normal sites. Since the conventional angiographic parameters analysed in this study failed to identify individual arterial sites with an increased risk for progression, definition of new angiographic parameters or application of new techniques seem mandatory to this end.

Constriction, Pathologic↗
PubMed1994

[Digoxin-induced constriction of epicardial coronary vessels in patients with coronary heart disease: reversibility by nitrates].

Heart diseases requiring glycoside therapy are often associated with coronary artery disease. This study evaluated quantitatively the effect of an intravenous bolus injection of digoxin (0.8 mg) on diameters of epicardial coronary arteries in 11 patients with coronary artery disease. Coronary angiograms were taken up to 30 min following intravenous administration of glycosides. The maximum decrease in mean diameters of angiographically normal coronary segments was 10.0 +/- 3.5% (p < or = 0.001) compared to control. Maximum reduction in minimal diameters of stenotic segments was 22.1 +/- 13.1% (p < or = 0.001). This vasoconstriction could be reversed with nitroglycerin. Thus, intravenous administration of digoxin induces vasoconstriction of normal and stenotic coronary arteries, which could cause ischemic complications in the presence of high-grade stenoses. Since digoxin-induced vasoconstriction could be reversed with nitroglycerin, concomitant vasodilator therapy is recommended.

Adult↗
PubMed1994

[Value of smoking cessation, physical training and psychological interventions in secondary prevention of coronary heart disease].

Smoking, physical inactivity, and psychological traits may have substantial impacts on the development and progression of coronary heart disease. In the secondary prevention of coronary heart disease quitting smoking presents the most effective single means. In numerous studies cardiac and total mortality of ex-smokers was reduced by 40-60% when compared to continuous smokers; this effect remained stable over the years or even increased. Regular physical activity is associated with a variety of coronary and cardioprotective mechanisms. Meta-analyses of controlled studies demonstrated a significant reduction in cardiac and total mortality by rehabilitation measures which included physical training. However, this effect diminished in the following years. Psychological measures can lower cardiac risks via several mechanisms. In two major controlled secondary prevention trials interventions aiming at psychological changes such as modification of "coronary prone" type A behavior or application of "stress" reduction measures resulted in a significant decrease in the number of clinical cardiac events during the treatment phase; however, data on the long-term effects beyond the intervention period are still insufficient. In conclusion, in the secondary prevention of coronary heart disease besides strict abstention from smoking a continuous physical training and eventually psychological care in special heart groups of as many qualified patients as possible seems recommendable.

Combined Modality Therapy↗
PubMed1993

Quantitative angiographic follow-up studies on the development of coronary artery disease: which coronary segments should be analyzed? Experience from INTACT.

Angiographic follow-up studies on the evolution of coronary artery disease are of increasing relevance. It has still to be evaluated which coronary segments are predominantly involved in the process of atherosclerosis and, thus, should be preferably included in the analysis. Therefore, the correlation of progression and regression of coronary disease with the diameter and location (proximal, mid or distal) of coronary segments was investigated from the data of the INTACT-study, in which 25 different coronary segments were defined including anatomic variants of rather distal segments. In 348 patients with coronary artery disease, standardized coronary angiograms were repeated within 3 years and were quantitatively analyzed (CAAS). In 1063 coronary stenoses (% diameter stenosis > 20%) compared from both angiograms, progression and regression were not influenced by diameter nor location of arterial segments. In the follow-up angiograms, the number of new lesions (stenoses and occlusions) per coronary segment differed with regard to segment diameter (> 3 mm: 64/1125 (6%); 2-3 mm: 139/1967 (7%); < 2 mm: 44/1756 (2%); p < 0.001) and location of segments (proximal: 86/1285 (7%); mid: 84/1193 (7%); distal: 77/2370 (3%); p < 0.001). Out of 77 distal new lesions, only 25 (32%) were found in segments < 2 mm in diameter. Since the absolute number of new lesions was high in distal coronary segments, but low in segments with diameters < 2 mm, angiographic follow-up studies should analyze coronary segments at any location, but may neglect segments with diameters smaller than 2 mm.

Coronary Angiography↗
PubMed1993

Progression of coronary artery disease is dependent on anatomic location and diameter. The INTACT investigators.

OBJECTIVES: This study represents the first prospective, quantitative analysis of the association of progression of coronary atherosclerosis with anatomic site and diameter. BACKGROUND: The progressive course of coronary artery disease has been documented in many angiographic follow-up trials. METHODS: The data of 348 patients with coronary artery disease from the International Nifedipine Trial on Antiatherosclerotic Therapy (INTACT) were reviewed. Standardized coronary angiograms were taken 3 years apart and were analyzed quantitatively. The coronary tree was subdivided into 25 segments. The progression of 1,063 preexisting coronary stenoses and the appearance of 247 newly formed stenoses was assessed in relation to the mean diameter of segments (< 2 mm, 2 to 3 mm, > 3 mm) and to their position in the coronary tree (proximal, mid, distal) and in the three major coronary arteries. RESULTS: Decreases in the minimal diameter of preexisting stenoses were largest in segments that were > 3 mm in diameter (mean +/- SD 0.23 +/- 0.5 mm vs. 0.10 +/- 0.4 mm and 0.02 +/- 0.3 mm, p < 0.001), in a proximal position (0.14 +/- 0.5 mm vs. 0.09 +/- 0.4 mm and 0.06 +/- 0.3 mm, p = 0.081) and in the right coronary artery (0.14 +/- 0.4 mm vs. 0.07 +/- 0.4 mm and 0.07 +/- 0.3 mm, p < 0.01). Changes in percent diameter stenosis of preexisting stenoses were lowest in segments that were < 2 mm in diameter and in a distal position (p = NS). The number of new stenoses/segment was lowest in segments that were < 2 mm in diameter (44 of 1,756 vs. 139 of 1,967 and 64 of 1,125, p < 0.001) and in a distal position (77 of 2,370 vs. 84 of 1,193 and 86 of 1,285, p < 0.001) and was highest in segments of the right coronary artery (100 of 1,546 vs. 66 of 1,496 and 72 of 1,492, p = 0.044). CONCLUSIONS: Progression of coronary artery disease occurs most frequently in coronary segments that are > 2 mm in diameter, in a proximal or midartery position and in the right coronary artery.

Coronary Angiography↗
PubMed1993

[Adverse effects of a new non-ionic contrast medium in heart catheterization].

Tolerance of a New Non-ionic Contrast Medium during Heart Catheterization The new non-ionic contrast medium iomeprol (CAS 78649-41-9) was investigated for adverse reactions and diagnostic quality in 75 patients undergoing heart catheterization. Blood pressure and ECG were continuously registered. The patients were asked for subjective complaints by using a standardized questionnaire. Experienced cardiologists assessed the diagnostic quality of the angiograms. With iomeprol neither fatal nor severe reactions were observed. The dye had only little influence on diastolic and systolic blood pressure; heart rate was not significantly influenced. Minor and partly moderate adverse reactions all being completely reversible were observed in 14 patients (18.7%). One patient complained of strong heat sensation after dye injection into the left ventricle. The diagnostic quality of the angiograms allowed to make a definitive diagnosis in all cases. Thus, iomeprol proved to be a suitable and safe contrast medium for heart catheterization.

Adult↗
PubMed1992

Concept of an antiatherosclerotic efficacy of calcium entry blockers. INTACT Investigators.

Animal experiments suggest an inhibitory effect of calcium entry blockers on arterial calcinosis and the formation of atherosclerotic plaques. Experiments with isolated tissues suggest various mechanisms for an antiatherosclerotic effect of calcium entry blockers. INTACT, the International Nifedipine Trial on Antiatherosclerotic Therapy, is the first study investigating, with a prospective, placebo-controlled, randomized, double-blind design, the influence of a calcium entry blocker (nifedipine 80 mg/day) on the progression of coronary atherosclerosis in patients with proven coronary artery disease. Study endpoints were changes of established coronary stenoses (diameter reduction greater than or equal to 20%), as well as the formation of new stenoses as documented by coronary angiography. Standardized coronary angiograms were taken before and after a treatment period of 3 years. The angiograms were quantitatively analyzed with the computer-assisted edge detection system CAAS. Of the 425 patients included in the study, 282 patients (134 on nifedipine and 148 on placebo) revealed no protocol violations. In the inclusion angiograms of these patients, 893 coronary stenoses were detected which were not significantly influenced in their development by nifedipine. However, 196 entirely new coronary lesions, 185 stenoses and 11 occlusions, were found in the follow-up angiograms. There were 78 lesions in 54 patients (40%) on nifedipine (0.58 new lesions/patient) and 118 lesions in 73 patients (49%; n.s.) on placebo (0.8 new lesions/patient; p = 0.031). In two other studies on the inhibiting effect of dihydropyridine calcium entry blockers on the progression of coronary artery disease in man defining angiographic endpoints, the drugs were also shown to reduce the number of newly formed significant coronary lesions. If further trials in man confirm a protective role of calcium entry blockers against the formation of atherosclerotic coronary lesions, a new strategy in the prevention of coronary artery disease has to be considered.

Animals↗
PubMed1992

Anatomical progression of coronary artery disease in humans as seen by prospective, repeated, quantitated coronary angiography. Relation to clinical events and risk factors. The INTACT Study Group.

BACKGROUND: At present, there is extensive knowledge on the clinical course of coronary artery disease (CAD), whereas data on the underlying anatomical changes and their relation to clinical events are still limited. METHODS AND RESULTS: We investigated progression and regression of CAD prospectively over 3 years in 230 patients (average age, 53.2 years) with mild to moderate disease by applying quantitated, repeated coronary angiography. Minimal stenotic diameters, segment diameters, and percent stenosis were analyzed by the computer-assisted Coronary Angiography Analysis System (CAAS). Progression was defined either as an increase in percent stenosis of preexisting stenoses by greater than or equal to 20% including occlusions or as formation of new stenoses greater than or equal to 20% and new occlusions in previously angiographically "normal" segments. At first angiography, we found 838 stenoses greater than or equal to 20% (average degree, 39.3%) and 135 occlusions in the four major coronary branches (4.23 lesions per patient). At second angiography, 82 (9.8%) of the preexisting stenoses had progressed, 15 of them up to occlusion (1.8%; preocclusion degree averaging 46.6%; 29.7-65.6%). In addition, there were 144 newly formed stenoses (average degree, 39.2%) and 10 new occlusions. Hence, 25 (2.6%) of all stenoses had become occluded. Altogether, 129 patients (56.1%) showed progression: 68 (29.6%) with new lesions only, 27 (11.7%) with preexisting lesions, and 34 (14.8%) with both types. Regression (decrease in degree of stenoses greater than or equal to 20%) was present in 29 stenoses (3.6%) and 28 patients (12%). The incidence of new myocardial infarctions was low, with three originating from occluding preexisting stenoses and one from new stenoses; hence, only four (16%) of the 25 new occlusions led to myocardial infarctions. Risk factor analysis showed that cigarette smoking correlated significantly with the formation of new lesions (p = 0.001), whereas total cholesterol correlated with the further progression of preexisting stenoses (p = 0.017) but not with the incidence of new lesions. CONCLUSIONS: In patients with mild to moderate CAD, the angiographic progression is slow (in this study 18.7% of patients and 7% of stenoses per year) but exceeds regression (4.1% of patients and 1.2% of stenoses per year). Progression is predominantly seen in the formation of new coronary stenoses and less in growth of preexisting ones. Most of the stenoses were of a low degree (less than 50%), clinically not manifest including those going into occlusion and leading to myocardial infarction. Progression was influenced by risk factors, especially cigarette smoking (formation of new lesions) and high cholesterol levels (progression of preexisting stenoses).

Constriction, Pathologic↗
PubMed1991

Percutaneous transluminal angioplasty of aortocoronary venous bypass grafts and effect of the caliber of the grafted coronary artery on graft stenosis.

The influence of morphologic parameters on the recurrence of stenosis after percutaneous transluminal coronary angioplasty of 49 stenoses in aortocoronary venous bypass grafts of 41 patients was investigated. Vessel dimensions were measured quantitatively. Angioplasty was successful in 46 stenoses (94%) of 38 patients (93%). In 35 patients (92% of successfully treated patients) with 42 stenoses, control angiography was performed after a mean interval of 189 +/- 186 days. In 9 patients (26%), 9 stenoses (21%) had recurred. The diameter of the grafted coronary artery distal to the anastomosis was significantly smaller in grafted arteries with than without recurrent stenoses (1.92 +/- 0.52 vs 2.45 +/- 0.50 mm; p less than 0.01). Recurrence also correlated with the ratio between graft diameter and coronary artery diameter greater than 1.35 (p less than 0.02) and with the stenosis length greater than 10 mm before angioplasty (p less than 0.01). Graft age, graft diameter and stenosis location in the graft had no significant influence on recurrence. Thus, the diameter of the grafted coronary artery and the length of the critical stenosis are parameters for recurrence after angioplasty of graft stenoses and should be considered in the selection of patients for this intervention.

Aged↗
PubMed1991

Substance P-like immunoreactivity and somatostatin-like immunoreactivity in the ventricular fluid of patients with chronic pain syndromes.

Substance P-like and somatostatin-like immunoreactivities (SPLI and SLI) were determined in ventricular fluid of patients with chronic pain syndromes and in a comparison group with multiple sclerosis, essential tremor, epilepsy and postanoxic myoclonus. Concentrations of SPLI and SLI were non-significantly decreased by 40% and 33% in chronic pain patients as compared with control patients without pain. There were no differences apparent between subgroups of pain patients (deafferentation pain, neoplasia-induced pain, thalamic pain). High pressure liquid chromatography combined with radioimmunoassay showed marked heterogeneity of SPLI and SLI.

Adult↗