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Biomedical subjects

R Erbel

Publications and source records attributed to R Erbel.

At least 199 records · Page 11Linked to original sources
PubMed1998

[Aortic rupture after blunt chest trauma. Rapid diagnosis using transesophageal echocardiography when radiographic and computed tomographic findings are unclear].

HISTORY AND CLINICAL FINDINGS: A 37-year-old woman who was not wearing a seat-belt while driving a car had a head-on collision at 70 km/h. On arrival of the emergency physician she was awake and responsive but complained of pain with bruising over the sternum and the epigastrium. Pressure on the sternum was painful. Arterial pressure was 95/60 mm Hg, heart rate 112/min. On admission the heart sounds were unremarkable and peripheral pulses normal. Vesicular sounds were heard over both lungs. In addition to multiple facial abrasions voluntary movements were impaired and the right knee-joint was swollen. INVESTIGATIONS: The ECG showed sinus tachycardia (103 beats/min) with left axis deviation, but was otherwise unremarkable. Initially the haemoglobin was 12.6 g/dl with normal white cell and platelet counts. Clotting tests, serum transaminases, creatine kinase, lactate dehydrogenase and other routine laboratory tests were within normal limits. TREATMENT AND COURSE: Because the haemoglobin level had fallen to 7.7 g/dl within the first 4 hours erythrocytes concentrate was infused. The chest radiogram and subsequent computed tomography showed a mediastinal and paraaortic haematoma of unclear origin. Transoesophageal echocardiography (TEE) demonstrated rupture of the descending aorta with free floating intraluminal parts of the intima in the isthmal region, just distal to the origin of the left subclavian artery, which was not occluded. Colour Doppler echocardiography revealed abnormal flow into mediastinal and paraaortic tissues. At operation the echocardiographic findings were confirmed and part of the descending aorta was replaced by a 3 cm dacron tube during an aortic crossclamping time of 37 min. The patient was discharged after a postoperative stay of average length, during which her other injuries were treated. CONCLUSION: After blunt thoracic or deceleration trauma earliest possible TEE is indicated, because it can at once provide details of extent and degree of injury to heart and/or aorta.

Accidents, Traffic↗
PubMed1998

[Comparison between PTCA and bypass operation. Results of large randomized studies].

BACKGROUND: The percutaneous transluminal coronary angioplasty (PTCA) and the coronary artery bypass surgery (CABG) are established therapy modalities for the coronary artery disease. Meanwhile, first results of randomized trials comparing both therapy forms have been published. PATIENTS AND METHODS: The results of the 6 large randomized trials (GABI, RITA CABRI, BARI, EAST, and ERACI) were compared and summarized. Inclusion criterium was coronary multivessel disease (in RITA also one-vessel-disease). Patients with left main stem stenosis, previous PTCA or CABG, severely depressed ejection fraction and total coronary occlusions were excluded in most trials. Between 127 and 1829 patients were randomized. Follow-up was 1 to 5 years. RESULTS: There was no significant difference in mortality between the PTCA and the CABG-group, except in the diabetic patients of the BARI trial, who showed a significantly better survival after CABG. Mortality was 3 to 7% in most trials. The rate of myocardial infarction in the follow-up did not differ significantly. The prevalence of angina was higher in the PTCA-group in the first months after the procedure, but the difference became less marked during the follow-up. One year after the procedure, approximately 75% of the patients in the CABG-group and 70% in the PTCA-group were free from angina. The rate of additional revascularization procedures was significantly higher in the PTCA-group (32 to 54%) than in the CABG-group (3.2 to 13%). Treatment costs were significantly higher in the CABG-group. CONCLUSION: Both therapy forms were very effective concerning treatment of angina without a significant difference in mortality or frequency of myocardial infarction. The PTCA patients required more revascularization procedures, the costs for their treatment were lower than in the CABG-group. The question, whether coronary stent implantation will influence these conclusions significantly, remains open.

Angioplasty, Balloon, Coronary↗
PubMed1998

Comparison of electron-beam computed tomography and intracoronary ultrasound in detecting calcified and noncalcified plaques in patients with acute coronary syndromes and no or minimal to moderate angiographic coronary artery disease.

We compared intracoronary ultrasound (ICUS) and electron-beam computed tomography (EBCT) on a coronary segmental basis in 40 consecutive patients with acute coronary syndromes and no or minimal to moderate angiographic disease (53+/-10 years; 34 men, 6 women). ICUS was used to define plaques, and EBCT was used to quantify coronary calcium (using a threshold of a CT density > 130 Hounsfield units in an area > 1.03 mm2). In a site-by-site analysis, coronary segments were defined as normal if both methods were negative, as containing noncalcified plaques if only ICUS was positive, and as containing calcified plaques if both methods were positive. A total of 222 coronary segments were analyzed (5.6+/-1.9 segments per patient). In 36 patients (90%), a total of 95 segments with plaques were identified, whereas in 4 patients (10%), only normal segments were seen. Of the 95 segments with plaques, 61 (64%) were calcified, and 34 (36%) were noncalcified. There was a linear relationship between the number of segments with calcified and with noncalcified plaques (r = 0.86, p <0.0001), but the mean relative frequency of segments with calcified plaques (55+/-38%) was highly variable. Calcium was found in 15 of 16 patients (93%) with 3 or more segments with plaques, while it was found in only 12 of 20 patients (60%) with one or 2 segments with plaques (p = 0.026). Younger age, higher low-density lipoprotein-cholesterol levels, diabetes, and active smoking predicted a higher relative frequency of segments with noncalcified plaques. Thus, in patients with acute coronary syndromes but no angiographically critical stenoses, there is a linear relationship between segments with calcified plaques versus segments with noncalcified plaques. However, while the mean ratio of these segments is close to 1:1, it is highly variable among individual patients.

Acute Disease↗
PubMed1998

Analysis of vessel wall morphology, blood flow velocity, and the hemostatic system in a patient with a large intracoronary thrombus.

A patient with AMI caused by a large thrombus in the proximal LAD was successfully treated with PTCA and an intracoronary lysis combined with the platelet-receptor antagonist c7E3. Analysis of cellular hemostasis after 1 and 6 months revealed a sustained platelet activation despite combined anti-platelet therapy with ASA and ticlopidine. A progredient slow-flow phenomenon appeared during control angiographies, confirmed by intracoronary Doppler examination.

Abciximab↗
PubMed1998

Extramural vessel wall hematoma causing a reduced vessel diameter after coronary stenting: diagnosis by intravascular ultrasound and treatment by stent implantation.

An extramural vessel wall hematoma occurred immediately after implanting a coronary stent in an in-stent-restenosis of the intermedius branch. Angiography showed a significant luminal reduction distal to the intervention site. Intravascular ultrasound revealed an extramural echolucent zone compressing the vessel lumen. Stent implantation compressed the hematoma and allowed adequate myocardial perfusion. This demonstrates the value of intravascular ultrasound (IVUS) in cases of unusual angiographic results which can help to manage complications after coronary intervention.

Coronary Angiography↗
PubMed1998

[Improved structure identification with tissue Doppler echocardiography].

Tissue Doppler echocardiography (TDE) has been shown to be of particular value in patients with impaired myocardial function. Recently, the technique was successfully employed to localize the ventricular insertion of accessory atrioventricular pathways. The identification of abnormal cardiac structures is coming up now as a new field of clinical interest. The purpose of this study was to differentiate anomalous cardiac and aortic from native structures by physical properties of tissue motion using transesophageal TDE. Characteristic motion patterns of anomalous structures have not been described in detail and tissue Doppler findings have not been associated with clinical features up to now. Forty consecutive patients were included after anomalous cardiac or vascular structures had been detected by conventional transesophageal echocardiography (TEE). A control group consisted of 20 subjects. Rapidity of diagnosis in anomalous structures was divided into 3 categories, and TDE signals were related to particular pathology by a blinded, 2nd observer. Three different motion patterns could be defined: incoherent motion due to free oscillation of an anomalous structure which is independent of the surrounding tissue (Figure 1b); coherent motion with a phase difference meaning that motion depends on the motion of the surrounding tissue but is out of phase (Figure 2); concordant motion showing no difference in direction, velocity, or phase of motion compared with the surrounding tissue. Incoherent motion was present in endocarditic vegetations, 4th degree aortic plaques, Chiari network, valvular prolapse, intracavitary tumors, and freely oscillating thrombi as well as in normal valve leaflets and papillary muscles. Especially if endocarditic vegetations are present its incoherent motion facilitates to recognize these small structures. The colorcode of this motion pattern demarcates the vegetation reliably from the surrounding tissue (Figure 1b). Within 15 seconds vegetations could be detected in 9 (82%) vs 2 (18%) patients employing only conventional imaging. Using conventional echocardiographic approaches detection of vegetations is frequently hindered by their small size and minor echo intensity (Figure 1a). In contrast, size and echo intensity do not affect the tissue Doppler signal. Normal papillary muscles and distal portions of the mitral and tricuspid valves were demonstrated to regularly meet the criterion of incoherent tissue motion in the control group. In part, this was also observed with respect to the aortic and pulmonary valves. In valvular tissue incoherent motion was caused by passive floating, whereas papillary muscles show an active inverse motion for short time intervals. Nevertheless, physiologic incoherent motion did not lead to any false differential diagnosis. The phase difference of coherent motion results from damped oscillation. This phenomenon was visualized by tissue Doppler M-mode in 5 thrombi of the left atrial appendage (LAA) (100%) and in 1 ventricular thrombus (50% of all clots). Concordant motion was shown in 3rd degree aortic plaques and postrheumatic and calcified vegetations. These structures were found to be completely embedded or closely attached, so that their passive motion corresponded to the motion of the surrounding regular tissue. Detection and assessment of anomalous structures are based on their motion patterns which can be synchronous or asynchronous in comparison with the surrounding tissue. Another goal of this investigation was to test if the sensitivity of TEE to spontaneous echo contrast can be improved using TDE. In 21 patients presenting with left atrial dilation (left atrial diameter > 44 mm) due to mitral stenosis (n = 8), mitral regurge (n = 5), arterial hypertension (n = 5) and multiple valvular disease (n = 3) fundamental multiplane TEE and transesophageal TDE were performed with standardized gain setting. The control group consisted of 20 randomized individuals with normal left

Aorta, Thoracic↗
PubMed1998

[Asynchrony of ventricular contraction and relaxation--pathophysiologically recognized phenomenon, now can be clinically assessed].

When regional myocardial dysfunction is present, the physiological pattern of ventricular filling and contraction is impaired. During acute coronary occlusion, characteristic changes are observed in the ischemic myocardial segment: the amplitude of the systolic wall thickening is reduced (hypokinesia), then virtually absent (akinesia) and finally replaced by a paradoxical outward motion (dyskinesia). The maximum amplitude is reached in early diastole ("post-ejection thickening"). Since hyperkinesis develops in the normal region, the ischemic and the normal region contract asynchronously. Experimentally left ventricular asynchrony can be detected by means of subendo- and subepicardially implanted ultrasonic crystals ("sonomicrometry") or by the analysis of the phase difference of the first Fourier harmonic of dysfunctional versus control myocardial wall motion. In the clinical setting, digitized cineventriculography, radionuclide angiography and digitized M-mode echocardiography were used to assess left ventricular asynchrony in patients with coronary artery disease and hypertrophic cardiomyopathy. However, these imaging modalities are time-consuming and require complicated off-line analysis. Tissue Doppler echocardiography (TDE) is a new ultrasound modality that is based on color Doppler principles and allows for quantification of myocardial wall motion velocity by detection of consecutive phase shifts of the ultrasound signal reflected from the myocardium. The Doppler signals are displayed as a color or pulsed Doppler image by rejecting low-amplitude echoes from the blood pool due to changes in thresholding and filtering algorithms. In addition, the ability to measure low velocity is improved in the TDE system so that the lowest measurable velocity is 0.2 cm/s, a velocity level associated with cardiac tissue motion (Table 1). Due to its high temporal and spatial resolution, TDE provides valuable information on regional myocardial wall motion during different intervals of the cardiac cycle. In healthy subjects, patients with coronary artery disease and patients with hypertrophic cardiomyopathy, tissue Doppler echocardiography was used to assess myocardial synchrony/asynchrony on a 2-fold temporal and spatial analysis. Peak myocardial velocities in different myocardial regions were detected during rapid ejection, isovolumic relaxation, rapid filling and atrial contraction (Figure 1). In the apical view, during the isovolumic relaxation time (IVRT) healthy subjects showed slow, synchronous outward motion of the septum and the lateral wall with homogeneous color-encoding (blue/green, Figure 2). Analysis of peak velocities revealed low, negative velocities in both the septum and the lateral wall (Figure 3). In patients with a significant luminal narrowing of the LAD myocardial asynchrony was detected during the isovolumic relaxation period: while the septum was moving inwards (red color-encoding with low, positive velocities), the lateral wall was moving outwards (blue/green encoding, low, negative velocities). A representative example of a patient with CAD is given in Figure 4. The M-mode analysis of the abnormally contracting interventricular septum reveals positive peak tissue velocities during the isovolumic relaxation period (Figure 5). In hypertrophic cardiomyopathy, TDE was able to detect an abnormal inward motion of the interventricular septum during IVRT and a delay in the onset of rapid filling (Figure 6). Thus, tissue Doppler echocardiography is a feasible method for the on-line detection of myocardial asynchrony. Sensitivity and specificity of the findings have to be explored in further, prospectively randomized trials.

Cardiomyopathy, Hypertrophic↗
PubMed1998

[Digital archiving of imaged heart catheter studies on CD-R. Detection of irreversible CD damage].

The digital archiving has great advantages compared to the standard 35-mm X-ray cinefilm documentation. The data are immediately available and quantitative coronary angiography possible. In addition the technical progress is enhancing the availability of data. The loss of films is nearly eliminated, as only copies of the digital archive data are delivered. In addition a big advantage concerning pollution is present, when CD Rs are used. We report about the damage of CD Rs after 89, 162, 181 and 252 days when they were stored in polypropylene material containing envelopes. The damaged CD Rs all belonged to the provider Verbatim, whereas CD Rs of the provider Rank Xerox or Kodak were never damaged. In contrary to the Verbatim company, Rank Xerox gave written confirmation for 10-year storage and a written confirmation, that the storage in the polypropylene envelopes is possible. Mechanical, thermal damage and damage by humidity have to be discussed as well as chemical interactions of the CD Rs surface with the polypropylene material. As the digital storage for X-ray images has to be provided for 10 years in Germany, it is concluded, that the storage in polypropylene envelopes has to be avoided, when a written confirmation by the company is not given. These observations should stimulate to better control and analyze the real storage availabilities of digital data and provide in the future other media than CD R for long-term archiving.

CD-ROM↗
PubMed1998

[Intravascular ultrasound--the new gold standard?].

Intravascular ultrasound (IVUS) has evolved to a research tool to an intrinsic part of modern invasive cardiology. The main reason is the capability to obtain "in-vivo" micro anatomy by means of miniaturized echo-transducers with an outer diameter of 2.9-3.5 French. For the first time it is possible to base decisions not only on lumenograms but also on vessel wall assessment. The capabilities of IVUS can be divided in its diagnostic and intervention associated potentials. The diagnostic strength of IVUS is the ability to monitor compensatory coronary artery enlargement as a response to arteriosclerosis, to assess intermediate lesions, to reveal occult left main stem disease, and angiographically "silent" arteriosclerosis. In conjunction with the estimation of intracoronary flow reserve, patients with the diagnosis of coronary "syndrome X" can be better classified into those with or without early signs of arteriosclerosis. Additionally, IVUS is at present the only method allowing the classification of coronary artery lesions according to the AHA/ACC Stary classification. The intervention associated potentials of IVUS are the ability to allow optimal device selection, i.e. rotablators in calcified lesions or atherectomy devices in large plaque burden. The effects of PTCA on vessel wall morphology can be studied in great detail and the effect on luminal gain can be assessed almost on-line. The correlation between IVUS and angiography for estimation of luminal dimensions is inferior, because angiography is not able to describe complex luminal geometries. Several groups showed that the residual plaque area even after angiographically successful PTCA lies still in the range of 60%. A significant reduction of this number may influence long-term outcome after PTCA. Minimal luminal areas and residual plaque area after PTCA seem to be an indicator of restenosis, while the presence or absence of dissections seem to be less predictive. Additionally, the main mechanism of restenosis after PTCA is vessel shrinkage, not intimal hyperplasia. Intravascular monitoring of stent expansion led to high-pressure stent deployment with significant increase in post-procedural luminal diameters and finally the ability to withhold anticoagulation in patients with optimal stent deployment and to lower subacute stent thrombosis rates. First results for IVUS guided PTCA show a superior gain in post procedural free lumen without an increased complication rate. In the future, integrated devices, like balloons on IVUS catheters, steerable catheters, integrated flow and pressure transducers, tissue characterisation, and 0.018 inch IVUS guidewires will further enhance the usefulness of IVUS.

Angioplasty, Balloon, Coronary↗
PubMed1998

[Hemodynamic effects of a single intravenous administration of prostaglandin E1 in a patient sample with chronic NYHA-stage II/III heart failure].

We investigated the hemodynamic effects of a single infusion of PGE1 (60 micrograms infused over a period of 2 h--this is the single dose used in courses of treatment for peripheral occlusive arterial disease) in patients with chronic heart failure NYHA class II-III. The ejection fraction of these patients was < 55%, their average age was 58.4 years (standard deviation 10 years), and their condition was stable. Nineteen of the patients had coronary heart disease and one patient had myocarditis. The hemodynamic data were obtained invasively by catheterization of the right and left heart. Blood pressure and pulse rate were measured manually. Intravenous infusion of 60 micrograms PGE1 over a period of 2 hours did not significantly alter contractility or hemodynamics. Dp/dtmax, dp/dtmax/p, and dp/dt DP40, which are parameters of left ventricular contractility, determined with the aid of a catheter-tip manometer, did not differ significantly over time from those in the placebo control group. Similarly, the other data furnished no evidence that administration of PGE1 had any hemodynamic or myocardial effects. Hence, it is reasonable to state that it is safe to administer PGE1 to patients with peripheral occlusive arterial disease.

Adult↗
PubMed1998

[Management of coronary perforation after percutaneous balloon angioplasty with a new membrane stent].

A 59 year old patient underwent percutaneous transluminal coronary angioplasty of a de novo stenosis of the proximal right coronary artery. Vessel perforation occurred after balloon angioplasty and was successfully treated by implantation of a new stent graft, which completely covered the perforation without residual leakage. Emergency coronary surgery could, thus, be avoided.

Angioplasty, Balloon, Coronary↗
PubMed1998

[New imaging methods for visualizing coronary arteries].

Techniques in the field of coronary artery imaging can be divided into two groups: invasive and non-invasive methods. Apart from the conventional coronary artery angiography, invasive methods include intracoronary ultrasound, intracoronary angioscopy, and optical coherence tomography. Non-invasive methods include magnetic resonance tomography, synchrotron-coronary angiography, and electron beam computed tomography. In the late 1980s, intracoronary ultrasound has come into clinical practice. It offers a real-time, cross-sectional image of the coronary artery in high resolution. Coronary arteries enlarge in the presence of atherosclerotic plaque formation in order to compensate for luminal narrowing caused by plaque formation (remodeling). With coronary angiography, the plaque formation cannot be detected until a lumen reduction of about 40-45%. With intravascular ultrasound, the early stages of atherosclerosis can clearly be demonstrated. In combination with the intracoronary Doppler technique, syndrome X can be differentiated. Another important role of intracoronary ultrasound in the diagnosis of coronary artery disease is to guide coronary interventions and to assess the result of coronary interventions especially to evaluate the result of stent implantation. Due to the clinical use of intracoronary ultrasound and the guidance of high pressure stent implantation, the incidence of acute stent thrombosis has decreased to about 1%. Coronary angioscopy portrays the surface of the vessel lumen. It is helpful to identify the mural thrombus especially to differentiate fresh and chronic thrombus formation. Magnetic resonance tomography is able to image the coronary arterial contour of the proximal segment. With today's gating technique, it is possible to portray the whole coronary tree and avoid disturbances resulting from the heart beat and respiration. Electron beam computed tomography is a very promising technique in screening for coronary artery disease. It is a very sensitive method to identify coronary calcification and, thus, to detect atherosclerotic plaque. Studies have shown that the presence of calcification almost invariably indicates the presence of coronary artery disease and that the absence of calcification can nearly rule out significant coronary artery disease. Moreover, a close correlation exists between the amount of calcification and the severity of coronary artery disease. Additionally, in combination with contrast injection, coronary artery perfusion can be evaluated. This is important to assess the conductance of coronary stent and bypass graft.

Coronary Artery Disease↗
PubMed1998

[Arguments against conventional balloon dilatation of recurrences within the stent].

Today, stent restenosis is the major limitation of coronary stent implantation. Despite several prospective randomized trials, which documented significantly lower restenosis rates after stenting compared to conventional balloon angioplasty for the treatment of de-novo stenoses, restenotic lesions, bypass graft stenoses and symptomatic dissections, in daily clinical practice restenosis rates after coronary stenting are reported between 18% and 78% depending on the lesions treated. Interventional treatment options for symptomatic stent restenosis include repeat balloon angioplasty, a combination of ablative approaches (rotablation, laser angioplasty, directional atherectomy) with balloon angioplasty, and stent-in-stent (sandwich technique) placement. Long-term success for the treatment of focal (< or = 10 mm) stent restenosis seems to be equivalent for all these strategies with a restenosis rate of about 30% while after balloon angioplasty of diffuse (> 10 mm) stent restenosis restenosis rates range between 35% and 85%. From a pathophysiological point of view it seems conclusive that balloon angioplasty can only achieve a limited lumen by plastic deformation of the obstructive neointimal tissue, which is responsible for stent restenosis. In this situation techniques, which ablate the neointimal tissue, can create a more adequate lumen without extensive vessel trauma supported by lower restenosis rates between 25% and 56% compared to balloon angioplasty alone. Prospective randomized trial are needed in the future to support a superiority of ablative techniques over conventional balloon angioplasty for the treatment of stent restenosis.

Angioplasty, Balloon, Coronary↗
PubMed1998

In vivo tomographic assessment of the heart and blood vessels with intravascular ultrasound.

Intravascular ultrasound (IVUS) has emerged from being a research tool to becoming an intrinsic part of modern invasive cardiology mainly due to imaging micro anatomy in vivo. For the first time, it is possible to base therapeutic decisions not only on lumenograms but also on vessel wall assessment. IVUS has both diagnostic and intervention associated potential. The diagnostic strength of IVUS is its ability to describe compensatory coronary artery enlargement as a response to arteriosclerosis, to assess intermediate lesions, and to reveal occult left main stem disease and angiographically "silent" arteriosclerosis. The intervention associated potential of IVUS is the optimal device selection, i.e., rotablators in calcified lesions or atherectomy devices in large plaque burden. The effects of PTCA on vessel wall morphology can be studied in great detail and the effect on luminal gain can be assessed. Several groups have shown that the residual plaque area ("plaque burden") even after angiographically successful PTCA still lies in the range of 60%. A significant reduction in this number may influence long-term outcome after PTCA. Minimal luminal area and residual plaque area after PTCA seem to be indicators of restenosis, while the presence or absence of dissections seems to be less predictive. The main mechanism of restenosis after PTCA is vessel shrinkage, not intimal hyperplasia. Intravascular monitoring of stent expansion led to high-pressure stent deployment with a significant increase in post-procedural luminal diameters and the ability to withhold anticoagulation in patients with optimal stent deployment. In pulmonary and aortic diseases, IVUS contributed significantly to the understanding of aortic dissection and pulmonary hypertension. Additionally, with intracardiac ultrasound left and right ventricular function can be assessed. Intracardiac ultrasound has gained clinical usefulness for guiding transcatheter ablation in patients with conduction system abnormalities. In the future, integrated devices, such as balloons on IVUS catheters, steerable catheters, integrated flow and pressure transducers, tissue characterization, and 0.018" IVUS guide wire will further enhance the usefulness of IVUS.

Arteriosclerosis↗
PubMed1998

Impact of routine angiographic follow-up after angioplasty.

BACKGROUND: There is an ongoing controversy as to whether repeat coronary angiography should be routinely performed after successful percutaneous transluminal coronary angioplasty (PTCA). METHODS: We examined the 10-year outcome in 400 patients who had or had not undergone an angiographic control 6 months after successful PTCA and a subsequent event-free 6-month period. Our comparison was based on data gathered by questionnaire and telephone interview in 315 patients with (group A) and 85 patients without (group B) a routine 6-month angiographic control. Multivariate analysis (Cox model) was performed to identify predictors of adverse events. RESULTS: During the 10-year follow-up period, 22 (7%) of the 315 patients in group A died, compared with 16 (19%) patients in group B (P= .003). In groups A and B, respectively, acute myocardial infarction occurred in 28 (9%) and 10 (12%) patients (not significant [NS]); coronary artery bypass grafting (CABG) was performed in 42 (13%) and 14 (16%) patients (NS); repeat PTCA was performed in 89 (28%) and 11 (13%) patients (P= .012); and serious adverse events (death, myocardial infarction, CABG) occurred in 76 (24%) and 32 (38%) patients (P= .02). Absence of a 6-month angiographic follow-up was identified as an independent predictor of death associated with a 2.7 times higher mortality rate during the 10-year follow-up period. Previous myocardial infarction increased the risk of death 2.5 times. Any increase of residual diameter stenosis by 10% was combined with a 1.4 times higher mortality rate. The chance of bypass surgery was higher in patients with multivessel disease (2.9 times), in patients with unstable angina (2.1 times), and in case of an increase of residual diameter stenosis by 10% (1.3 times). No predictor for the risk of myocardial infarction was found. Angiographic follow-up increased the likelihood of PTCA 2.5 times. CONCLUSIONS: A routinely performed angiographic control 6 months after successful PTCA is associated with a significantly higher rate of repeat PTCA but, most important, is correlated with a significantly lower mortality rate during the 10-year follow-up period.

Adult↗
PubMed1998

Current concepts of coronary flow reserve for clinical decision making during cardiac catheterization.

Measurements of coronary flow reserve, once used only for research, have gained wide acceptance as an additional diagnostic approach in the decision-making process of diagnostic cardiac catheterization and coronary interventions. Apart from the noninvasive determination of coronary flow reserve, intracoronary Doppler flow wires have facilitated decision making in the catheterization laboratory. Different techniques, unstandardized procedures, and data from uncomparable patient populations have remained a confounding factor. This review examines current concepts of coronary flow reserve as well as methodologic considerations and pitfalls. Applications of coronary flow reserve for periinterventional assessment are evaluated on the background of practical guidance. According to a detailed examination of arterial structure and function, a normal coronary flow reserve exceeds a value of 3.0. Values below 3.0 suggest involvement of microvascular disease caused by functional or structural alterations. The influences of various factors such as age, hemodynamics, hypercholesterolemia, hypertrophy, hypertension, syndrome X, and coronary artery disease are discussed in relation to the effect on coronary flow reserve. From available information, measurements of coronary flow reserve are an adjunct to current interventional technology to optimize individual patient care. Further efforts should be undertaken to incorporate these new methods into our routine clinical decision making.

Blood Flow Velocity↗
PubMed1998

Measuring the effect of risk factors on coronary atherosclerosis: coronary calcium score versus angiographic disease severity.

OBJECTIVES: This study sought to determine whether noninvasive quantification of coronary calcium is comparable to selective coronary angiography in measuring the effect of cardiovascular risk factors on coronary atherosclerosis. BACKGROUND: Electron beam computed tomography (EBCT) allows the delineation of anatomic coronary atherosclerotic disease and may be useful for noninvasively defining the role of established and new cardiovascular risk factors in selected patient groups. METHODS: A total of 211 consecutive patients, 26 to 79 years old, referred for evaluation of suspected or recently diagnosed coronary artery disease were examined. Selective coronary angiography was used to define five angiographic disease categories: normal coronary arteries, nonobstructive disease and one-, two- or three-vessel disease. EBCT was used to calculate coronary calcium scores, and cardiovascular risk, including lipid variables and fibrinogen levels, was assessed. RESULTS: Coronary calcium score and angiographic disease severity categories were largely predicted by identical risk factors (i.e., age, male gender, total/high density lipoprotein cholesterol ratio, fibrinogen) and, to a lesser degree, hypertension. Only smoking predicted angiographic disease severity but not calcium scores. The risk factors together explained a comparable proportion of the variability in angiographic disease categories and in calcium score quintiles (33% vs. 41%, p=0.16 by bootstrap analysis). An overall risk score composed of these risk factors separated angiographic disease categories and calcium score quintiles with a similar area under the receiver operating characteristic curve ([mean+/-SE] 0.81+/-0.03 vs. 0.83+/-0.03, p=NS). CONCLUSIONS: Quantification of coronary calcium is comparable to selective coronary angiography in measuring the effect of established cardiovascular risk factors on coronary atherosclerosis. Thus, EBCT may be useful for the noninvasive evaluation of the relations between conventional or developing cardiovascular risk factors and coronary atherosclerosis.

Adult↗