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We report about a 67-year old man, who was submitted to our clinic with acute coronary syndrome. The cardiac catheterization showed a proximal thrombus in the left anterior descending (LAD). The other coronary arteries did not have significant lesions. After percutaneous transluminal coronary angioplasty with stent-implantation into the proximal LAD the patient remained clinically stable. Cardiac enzymes confirmed no myocardial necrosis. Three days after the acute coronary syndrome the patient developed a podagra, which was treated with colchicinum, diclofenac and local cooling. Five hours after initial therapy the patient developed severe symptoms of angina pectoris and electrocardiographical signs of an acute posterior and anterior myocardial infarction. Immediate coronary angiography demonstrated extended vasospasm of the right coronary artery. Intracoronary application of verapamil and nitroglycerin resolved the coronary spasm. The patient reported about a self-indicated application of diclofenac six hours before hospital admission. This case demonstrates that oral application of diclofenac can provoke coronary vasospasm.

Today's definition of coronary artery disease (CAD) comprises two forms: obstructive and non-obstructive CAD. The 31-72% chance of a life-threatening event-like a myocardial infarction-with non-obstructive CAD is well documented in numerous studies. The objective in modern strategies of diagnosis and therapy should therefore be expedient identification of patients at high risk for coronary events, who will benefit from a customized therapy. Before initiating diagnostic procedures of CAD, a well defined strategy should be pursued. There are two possible primary objectives: ASSESSMENT OF THE INDIVIDUAL RISK FOR A CORONARY EVENT: Assessment of the individual "absolute" risk for a coronary event is not possible using single traditional risk factors. The individual risk can be estimated by integrating several of the traditional risk factors into a scoring system. These so-called risk scores (e.g. Framingham score and Procam score), however, have been associated with shortcomings: insufficient discrimination of high-risk from low-risk individuals. The calcium score has therefore become increasingly established; this Agatston score is independent of the traditional risk factors, so there is no correlation between Agatston and Procam scores. Today, the calcium score is considered the superior test for identifying individuals at high risk for a coronary event and its use is recommended by the European Society of Cardiology (ESC) guidelines for prevention of cardiovascular diseases. PROOF OR EXCLUSION OF A HEMODYNAMICALLY SIGNIFICANT CORONARY STENOSIS: Another concept is the definitive proof or exclusion of a hemodynamically "significant" coronary narrowing. The probability of an obstructive CAD is traditionally assessed by the type of chest pain, age, gender and stress-ECG. In patients with a low probability of an obstructive CAD, cardiac catheterization is not indicated, whereas in patients with a high probability of a hemodynamically significant coronary stenosis, an invasive strategy should be performed. Since non-invasive coronary angiography (CTA) with cardiac-CT has been shown to provide a high negative predictive value, CTA (with good imaging quality) is suitable for ruling out a significant obstructive CAD in the group at intermediate risk for an obstructive CAD. Another approach could be a functional test to initially prove a relevant, inducible myocardial ischemia: In a large cohort it was shown that patients will only prognostically benefit from revascularization procedures if the ischemic myocardial area is greater than 10%. Therefore, the assessment of the extent of myocardial ischemia is the domain of modern stress imaging tests. Stress-echocardiography and myocardial scintigraphy have almost the same sensitivity (74-80%, 84-90%, respectively) and specificity (84-89%, 77-86%, respectively), which are considerably higher than for stress-ECG. Cardiac MR is most suitable for the assessment of myocardial perfusion, because it traces the first pass dynamics of gadolinium at rest and during stress in reproducible slices at an acceptable spatial and a high temporal resolution without ionizing radiation. Whether the non-invasive coronary angiography with cardiac-CT and the Adenosin-perfusion imaging with cardiac-MR will completely replace diagnostic cardiac catheterization and stress-echocardiography as well as myocardial scintigraphy remains to be evaluated in further studies.

Objective: The electron-beam computed tomography-(EBCT-)derived calcium score provides a measure of coronary atherosclerotic plaque disease which may allow for more precise risk stratification in symptomatic patients. However, it remains unclear if EBCT can add prognostic information compared with the clinical information derived from risk factor assessment, exercise stress testing, and coronary angiography., Methods and Results: A cohort of 300 consecutive patients with recent (<3 months) onset of symptoms was retrospectively identified who were examined for possible coronary artery disease (CAD) and who all underwent EBCT. Successful follow-up after 3.5 years was obtained in 255 (85%) patients whose mean age at baseline was 58+/-11 years (n = 181 (71%), males). Four clinical categories with increasing evidence of CAD were constructed on the basis of risk factor assessment, exercise stress testing, coronary angiographic anatomy, and coronary revascularization at baseline. During follow-up, major adverse cardiac events (MACE: myocardial infarction, cardiac death, revascularization) were observed in 40 (16%) patients, including myocardial infarction and cardiac death in 5 patients. The 4 clinical categories were highly predictive of MACE, with a relative risk estimate of 28.3 (95% CI, 6.7-119.1) in the upper vs. the reference category. In univariate analysis, the relative risk estimate of MACE associated with a calcium score > or =100 was 12.0 (95% CI, 4.7-30.6). After adjustment for the clinical categories and for age, this estimate decreased in multivariate analysis, but remained predictive at 4.4 (95% CI, 1.5-12.6)., Conclusion: In patients with first-time evaluation of possible CAD, EBCT-derived coronary calcium is suggested to provide for independent and additional information compared with the clinically available information.

Recently, in a cross-sectional study, a correlation of moderate degree was documented between serum BNP (brain natriuretic peptide) and exercise capacity in patients with chronic heart failure (CHF). However, it remains unknown if BNP, which increases in response to high myocardial wall stress, is sufficiently sensitive for changes in exercise capacity during clinical follow-up. To elucidate this, 42 CHF patients were recruited and randomized into a training (T; 58 +/- 10 years; n = 14 NYHA II; n = 5 NYHA III) and a control group (CO; 54 +/- 9, n = 17 NYHA II; n = 6 NYHA III). T carried out 12 weeks of endurance training on a cycle ergometer (4 sessions per week, 45 min duration). Venous blood sampling and cycle ergometry with simultaneous gas exchange measurements were carried out prior to and after the experimental phase. Due to its superior stability during laboratory procedures, NTproBNP was determined instead of BNP. Both proteins are secreted in equimolar amounts and share an identical diagnostic meaning. In both groups, NT-proBNP decreased slightly (T: from 1092 +/- 980 to 805 +/- 724 pg x ml(-1); CO: from 1075 +/- 1068 to 857 +/- 1138 pg x ml(-1); T vs CO: p = 0.65). Anaerobic threshold (AT) as a measure of exercise capacity went up in T (from 0.96 +/- 0.17 to 1.10 +/- 0.22 l x min(-1)) but remained almost constant in CO (pre: 1.02 +/- 0.27; post: 1.00 +/- 0.27 l x min(-1); T vs CO: p < 0.001). The correlation between changes in NT-proBNP and changes in AT remained insignificant (r = 0.02, p = 0.89)-even if only T was considered (r = 0.09, p = 0.72). Improved exercise capacity in CHF patients due to 3 months of endurance training is not reflected in the course of NT-proBNP. These findings are inconsistent with a sufficient sensitivity of this parameter to detect changes in exercise capacity during clinical follow-up. Changes in NT-proBNP beyond its spontaneous variability are more likely to be detected following therapeutical interventions which aim more clearly at the myocardium. In determining alterations of functional capacity ergometric testing cannot be replaced by serial determinations of NT-proBNP.

Methods: Time and frequency domain analysis were conducted during a period of 600 s each. We performed a special protocol consisting of five different "pacing" periods: 1) recording of normal sinus rhythm (SR1); 2) atrial pacing with a rate 15% higher than the intrinsic heart rate; 3) ventricular pacing triggered by atrial activation (VAT, with a short AV-delay of 80 ms); 4) AV-sequential pacing with an atrial rate 15% higher than the intrinsic heart rate and a very short AV delay of 80 ms (DDD); 5) normal sinus rhythm (SR2). Only patients with normal AV-nodal conduction or with AV-block I degrees were included. The influence of a structural heart disease as well as a non-sustained VT on Holter ECG and a depressed EF on HRV parameters were analyzed using a multivariate analysis. All patients were lying in a supine position. Blood pressure was measured continuously and the frequency of breathing was controlled., Results: No differences in HRV between the two sinus rhythm periods SR1 versus SR2 could be detected. Neither SR1 vs VAT showed a significant difference for SDNN and r-MSSD. In contrast, HRV during SR1 compared to AAI, and HRV during VAT compared to AAI were significantly different (p < 0.001). When comparing HRV during DDD, which should be zero, and AAI, we found a significantly lower SDNN and r-MSSD (1.2 ms vs 4 ms, p < 0.04). The presence of structural heart disease, a non-sustained ventricular tachycardia, a depressed ejection fraction of less than 0.50 did not reveal a significant influence on the HRV parameters (multivariate analysis). The mean Wenckebach in patients with structural heart disease tended to be greater (437 ms vs 350 ms, p = 0.05); an increase in the Wenckebach was not correlated to a change in HRV parameters (p = ns)., Conclusion: Heart rate variability derived from consecutive RR-intervals is predominantly caused by periodicity in sinus-node impulse formation. A conduction variability of the AV-node exists, but is very low. The presence of a structural heart disease, a non-sustained ventricular tachycardia on Holter ECG, as well as a depressed ejection fraction of less than 0.50 showed no significant influence on the HRV parameters. Therefore, one can apply the calculation of heart rate variability for risk stratification in patients suffering from structural heart disease and moderate AV-nodal conduction disturbances. Attenuation of the oscillation of the heart rate, i. e. heart rate variability (HRV), is associated with an increased risk for mortality in patients with structural heart disease. Many of these patients also suffer from conduction disturbances, e. g. AV-nodal conduction delays. Whether the calculation of HRV in those patients is recommendable has not been investigated yet. Therefore, we conducted a study consisting of 20 consecutive patients in order to determine the formation of HRV, the influence of structural heart disease, the presence of a nonsustained ventricular tachycardia (VT), and a reduced ejection fraction (EF) on the HRV parameters during an elective electrophysiologic study.

Background: Ventricular late potentials detected by the signal averaged electrocardiogram (SAECG) have been used to predict cardiac death in patients after recent myocardial infarction. The goal of this study was to investigate the prognostic significance of the SAECG in a population of chronic coronary artery disease, with and without previous myocardial infarction., Methods: SAECG was recorded in 698 patients with angiographically proven coronary artery disease and analyzed by time domain analysis (TDA) and by spectral temporal mapping (STM). Cardiac death or ventricular fibrillation (= cardiac event) were used as the primary endpoint for follow-up (25 to 33 months)., Results: A cardiac event occurred in 46 out of 698 patients (6.6%). An abnormal SAECG using TDA was found in 43% of patients with a cardiac event, as compared to 21.7% in those without (p<0.0005). The probability of a cardiac event during follow-up was 4.4% when TDA and STM were both normal, 9.5% and 10.2% when either STM or TDA were abnormal and 28.5% when both were abnormal. A duration of the averaged QRS complex of more than 120 ms and a left ventricular ejection fraction of less than 45% were the only independent predictors of a cardiac event. Logistic regression analysis could predict a cardiac event with a sensitivity of 54% and a specificity of 88%., Conclusions: In patients with chronic coronary artery disease the duration of the signal averaged QRS complex and left ventricular ejection fraction are independent predictors of cardiac death or ventricular fibrillation.

Antithrombotic therapy in acute coronary syndrome without ST-segment elevation should be initiated with aspirin 100 mg/day (loading dose 250-500 mg) and Clopidogrel 75 mg/day (loading dose 300 mg). In addition, anticoagulation with unfractionated heparin or low molecular weight heparin should be started. A GP IIb/IIIa receptor blocker can be given either upfront (Eptifibatide/Tirofiban) or directly in the cathlab preceding PCI (Abciximab). Aspirin should be given in the chronic phase lifelong, Clopidogrel for at least nine months. An invasive strategy is recommended in high-risk patients within 48 hours.

Atherosclerotic artery disease is a systemic vascular disorder typically involving multiple vascular territories in the same patient. To assess the prevalence and the topographic distribution of non-coronary peripheral artery disease (PAD), cerebrovascular (CVD) and renal artery disease (RAD) in patients with an angiographically confirmed coronary artery disease (CAD) a cross-sectional survey among inpatients admitted for symptoms of CAD was performed. The relationship between CAD and multiterritory vascular disease, and the major risk factors were also assessed. A total of 1855 consecutive patients, mean age 65 +/- 10.6 years (18-92 years), 1184 (63.8%) men and 671 (36.2%) women with an angiographically confirmed CAD were studied. The patients were divided into four age groups: group A < 35 years of age, group B 35 to 54 years, group C 55 to 74 years and group D > or =75 years of age. While 1265 (68.2%) had no evidence of a relevant non-coronary artery disease, in 590 (31.8%) a significant non-coronary artery disease in at least one additional major vascular territory was documented. CAD was most frequently associated with PAD in n = 176 (9.5%) patients. In 22 (1.2%), all four studied vascular territories were significantly diseased. The prevalence of the multi-territory artery disease increased with age: lowest in group A and highest in the group D. However, the data analysis by gender revealed the highest prevalence of CAD associated with PAD and RAD, respectively, in women 35 to 54 years of age. Using the multivariant logistic regression model, type II diabetes was the only major risk factor for a multi-territory expression of atherosclerosis.

Cardiac involvement in patients with systemic lupus erythematosus (SLE) is common. The natural history of the cardiovascular manifestations has been altered by systemic corticosteroids used for the treatment of SLE; thus, young patients with SLE may suffer from angina and myocardial infarction. The surgical problems and special requirements in patients with SLE are discussed. CAD is one of the major complications limiting the prognosis of the patient with SLE. In the future, a large number of SLE patients may be candidates for myocardial revascularization. In our opinion, total autogenous arterial bypass grafting is advised and intraoperative biopsies of the LIMA are meaningful in patients with SLE.

Feasibility and reliability of a 12 lead electrocardiogram (ECG), recorded by the patient himself and transmitted via telephone are mandatory for prehospital diagnosis of myocardial ischemia in patients with coronary heart disease. In this study, a 12-lead ECG recorded by patients and transmitted to the cardiology call center via telephone (Tele-ECG; model CG-7100; Card Guard) was compared with the conventional 12-lead ECG from the same patient recorded at the same time in 128 cases. The Tele-ECGs received by the call center were compared with conventional ECG by two cardiologists and one internist independently and blindly. In relation to the conventional ECG, reproducibility of PQ, QRS and QT-durations [ms] as measured in the Tele-ECG was 85%. Concordance between Tele-ECG and conventional ECG in the detection of negative T-waves was very high (Kappa value (kappa) 0.94, 0.96 and 0.97), respectively, depending on the physician. ST-segment changes were diagnosed correctly in most of the cases in Tele-ECG (kappa=0.98-0.99), as compared with the conventional ECG by all physicians. Concordance between Tele- and conventional ECG concerning the pattern of old myocardial infarction was very high (kappa=0.99) for all infarct localization. The limitations of Tele-ECG were of technical nature. In 14 cases, the peripheral electrodes were displaced; in 12 cases, there were baseline artifacts. These technical errors could be corrected in 126/128 patients (98.4%) by transtelephonic verbal communication. In conclusion, the reliability and feasibility of the 12-lead Tele-ECG-recorder used in this pilot study could be demonstrated. In an ongoing randomized controlled multicenter study, it is being investigated whether the strategy of prehospital diagnosis of acute coronary syndromes by Tele-ECG in combination with verbal communication is able to reduce pre- and in-hospital time delay, to avoid unnecessary hospital admissions and to reduce the economic burden of coronary heart disease.

Exercise training for patients with coronary artery disease (CAD) is recommended in a wide range between 40-85% of maximum functional capacity (MFC) or 55-90% of maximum heart rate (HR). During exercise, high levels of catecholamines and metabolic acidosis could induce arrhythmia and ischemia. But catecholamines have never been determined in CAD during constant load exercise in the upper range of recommended intensities. In 11 CAD patients (age 58+/-8 years, BMI 26.1+/-4.0 kg x m(-2), NYHA I n=7, II n=4) we tested the maximum functional capacity (MFC), norepinephrine (NE), epinephrine (E) and blood lactate ([Lac(-)](B)) in a symptom-limited incremental ergometer test. Related to the exercise recommendation, the kinetics of NE, E and [Lac(-)](B) were determined in two 30 min constant load tests in randomized order: one was performed at the anaerobic lactate threshold (CTAT), a second was performed 10% above the individual threshold intensity (CT+10%). In the incremental tests maximum workload and VO(2) were 141+/-54 W and 1766+/-532 ml x min(-1), respectively (85+/-22% of normal; [Lac(-)](B) 5.7+/-1.9 mmol x l(-1), HR 138+/-28 b x min(-1), NE 11.7+/-5.1, E 1.6+/-1.4 nmol x l(-1)). In CTAT the anaerobic threshold (63+/-7% of MFC) represented the mean range of recommended exercise intensity for CAD (40-85%) and could be validated as steady-state intensity because catecholamines and [Lac(-)](B) concentrations remained constant after the initial increase (workload 88+/-35 W, [Lac(-)](B) 3.3+/-1.4 mmol x l(-1), HR 117+/- 23 b x min(-1), NE 8.3+/-3.5, E 0.8+/- 0.7 nmol x l(-1)). In all patients CT+10% (71+/-7% of MFC) led to a continuous rise in [Lac(-)](B), to a NE overload and to earlier exhaustion, although the intensities were in the recommended training range (workload 100+/-38 W, [Lac(-)](B) 5.8+/- 1.9 mmol x l(-1), HR 129+/- 29 b x min(-1), NE 13.9+/-6.9, E 1.5+/- 1.7 nmol x l(-1); p<0.01 against CTAT for all except E). Conclusions In the upper range of recommended training intensity for CAD patients, norepinephrine and lactate were higher during endurance exercise than at MFC in incremental tests. Endurance exercise with intensities >70% of MFC could overload the cardiac patient and increase the risk of arryhthmia and ischemia. Therefore, endurance exercise should be performed below 70% of MFC or below 85% of maximum HR, respectively, whereas higher intensities should apply to interval exercise.

Chronic cardiac insufficiency is an illness with increasing epidemiological importance and mortality. Therefore different invasive and non-invasive investigation methods for early recording were developed. The left ventricular ejection fraction (LVEF) has played a special role in this direction. The determination of the contractile reserve by means of non-invasive measurement of blood pressure and flow through the aortic valve is a new and up to now widely unknown method for recording the capability and power reserve of the of myocardium. Since no comparative investigations are known from literature and results from a follow-up are not available yet, we tested whether, by means of contractile reserve, the discrimination of subjects with different cardiac power is possible or not. Forty-two men between 44 and 62 years of age belonging to three groups with different cardiac power (persistence trained, healthy subjects and patients with CHD) were examined non-invasively. The main result of the study is that it is possible to distinguish between the three groups significantly by means of the contractile reserve. The largest value (15.25 W +/- 3.46 W) was found in the "persistence trained" group, followed by the "healthy subjects" (10.85 W +/- 4.19 W). The smallest values were from the "patients" group (7.88 W +/- 2.95 W). The differences between the mean values of the CHD "patients" and the "persistence trained" were significant (p < 0.001). Similar comparisons of the groups of "healthy subjects" and "trained persons" and "healthy subjects" and "patients", respectively, yield p values of p = 0.007 and p = 0.040. These differences are also significant. This study is a first investigation and description of the method. A validation only can be achieved by follow-up investigations.

Coronary stenting has become the primary therapeutic option for many coronary lesions. As opposed to conventional stenting the advantages of direct stenting are a reduction of procedural time, radiation exposure and costs. However, data about the incidence of in-stent restenosis are so far not available. It was the aim of this prospective study to compare the expansion of the Multilink stent after direct stenting and predilatation by quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). Between January 2000 and June 2001, 82 patients were assigned to direct stenting (46 lesions) or predilatation (40 lesions) in lesions of coronary arteries > 3 mm. The procedural success rate was 92% in patients undergoing direct stenting. The baseline clinical characteristics were similar in both groups. The comparison of the angiographic data shows that direct stenting was performed in lesions with a lower degree of stenosis (71 +/- 12% vs 79 +/- 11%, p = 0.01) and that significantly shorter stents were used (14.4 +/- 3.0 vs 17.8 +/- 4.1 mm, p = 0.0007). The mean stenosis length was not significantly different in either group (10.5 +/- 3.4 vs 11.7 +/- 4.3 mm, n.s.). The QCA data after stent implantation show no differences of either implantation technique. Stent expansion was assessed by IVUS estimation of the proximal, distal and minimal in stent area. The minimal in-stent area (9.53 +/- 3.23, mm2 vs 8.65 +/- 1.96 mm2, n.s.) and the stent symmetry index (0.88 vs 0.88 n.s.) were not different in either patient group. These results indicate that in this subset of selected coronary lesions > 3 mm, elective stent implantation with and without predilatation effectively can achieve comparable stent expansion as assessed by QCA and IVUS. In comparison to conventional stent implantation stents, which were implanted without predilatation, were significantly shorter to cover the same lesion length.

The routine use of sensor-tipped guide wires for the assessment of functional coronary lesion severity has become widespread in the catheterization laboratory. The physiological parameters derived from pressure or flow velocity measurements, fractional flow reserve, relative and absolute coronary blood flow velocity reserve show a high agreement with noninvasive stress testing for myocardial ischemia. However, since these parameters are based on either intracoronary pressure or flow velocity, they do not investigate the hemodynamics of the coronary circulation completely, leading to ambiguous or conflicting outcomes. Only the use of simultaneously measured distal pressure and flow velocity will avoid any possible misinterpretation of the data. We have successfully used an index of stenosis resistance during maximal hyperemia to characterize the functional significance of a coronary stenosis. Recent developments in guide wire technology, currently used for research investigations, put these simultaneous measurements within clinical reach.

Objectives: Determination of fractional flow reserve (FFR) allows the functional assessment of coronary stenoses before and after an intervention. Preliminary data suggest that a FFR > or = 0.94 is associated with an excellent clinical outcome after stent implantation. However, these results were limited both by the number of patients included and the use of non-contemporary stent designs. We sought to determine the prognostic value of FFR measurements in a large patient cohort undergoing coronary stent implantation., Methods: Eighty-nine consecutive patients were enrolled in whom a stent implantation was performed and a pressure wire was used as a guide wire. Patients were followed for at least 6 months. Death, myocardial infarction (MI) and target vessel revascularization (TVR) were considered cardiac events. A FFR > or = 0.94 was regarded as an optimal functional result., Results: A complete follow-up was available in all patents. Pre-interventional FFR increased from 0.66 +/- 0.16 to 0.95 +/- 0.05 (p < 0.0001) after stent implantation. Sixteen (18%) events occurred during follow-up including 10 (11.2%) TVR. Final FFR was significantly higher in patients without compared to patients with an event (0.92 +/- 0.06 vs. 0.96 +/- 0.05, p < 0.003). By univariate analysis, the presence of diabetes mellitus, left ventricular function, residual diameter stenosis and final FFR were associated with a worse clinical outcome. In the multivariate analysis, only the final FFR and left ventricular function remained as significant predictors for cardiac events (relative risk, 3.50; 95% CI: 1.29-9.52, P < 0.014, and 0.97; 95% CI: 0.93-1.00, p = 0.047)., Conclusion: These results demonstrate in a nonselected patient cohort a strong correlation between FFR values after coronary stenting and subsequent cardiac events. Further studies have to investigate whether outcome after stenting might be improved by guiding the procedure with a pressure guide wire.

Background: The rapidly expanding number and scope of health technologies used in the prevention, diagnosis, and treatment of coronary heart disease present physicians and policy makers with complex decisions that must be made even under uncertainty about the risks and benefits of these procedures. A physician must determine which procedures offer the best trade-off between potential harm and benefit, and yield the maximum expected health benefit for the patient. In addition, the cost-effectiveness of alternative choices must be considered to optimize resource allocations from a societal perspective, further complicating the decision making process., Methods: Decision analysis is the application of explicit and quantitative methods to analyze decisions under conditions of uncertainty. Briefly, the basic concepts of decision analysis and cost-effectiveness analysis are described. Three examples of decision-analytic models for the prevention, diagnosis, and treatment of coronary heart disease are discussed to demonstrate situations in which decision analysis may be helpful, and to introduce different methodological approaches., Conclusion: Decision analysis may aid clinical decisions affecting individual patients as well as inform clinical policy decisions and decisions regarding national health policy. However, this method is not a complete procedure for determining resource allocation decisions in health care, because it cannot incorporate all the values relevant to such decisions.

Better MR image quality of coronary arteries and coronary grafts is the product of increased spatial and temporal resolution. Breathing artifacts could be reduced by implementing breath-holding and navigator techniques. With these developments normal coronary arteries can often be imaged reliably. Several trials have been performed in order to test the reliability of MR angiography to detect coronary artery stenosis. But up to now, sensitivity and specificity have proven to be too low to introduce these techniques in clinical routine. The patency of coronary grafts can be detected reliably using different MR techniques. Coronary flow reserve can be measured using the MR phase contrast technique. This noninvasive approach was tested in diseased coronary arteries and in graft stenoses. A reduced MR coronary flow reserve corresponded to reduced flow reserve measured invasively. Measurement of MR flow reserve in normal and diseased coronary grafts revealed significant differences (3.3 +/- 0.4 vs. 1.3 +/- 0.2).

As the number of diagnostic coronary angiographies without subsequent revascularization procedures is continuously rising, the need for non-invasive diagnostic procedures with a high diagnostic accuracy is well appreciated. Because of the technical advances in magnetic resonance imaging (MRI) over the last few years, major improvements have been made in the functional assessment of wall motion, myocardial perfusion and coronary flow measurements, as well as the visualization of the anatomy of the coronary arteries by MRI. Besides these classical parameters of ischemia and anatomical pathology, for the first time MRI might offer the possibility to not only non-invasively assess the lumen of the coronary arteries, but also to visualize the vessel wall. Thus, early manifestations of coronary artery disease may be detectable for the identification of patients with preclinical disease as candidates for aggressive risk modification. In this review the current status as well as future perspectives of MRI are discussed.

Intracoronary irradiation is currently the most promising approach to reduce restenosis after percutaneous transluminal coronary angioplasty. Meanwhile numerous data are available concerning efficacy and safety of this novel method. These data confirm the results of preclinical studies that reported a dramatic reduction of neo-intima proliferation and negative remodeling. However, the number of reports on an elevated incidence of late stent thrombosis (> 30 days post intervention) are increasing. It is commonly suggested that the delayed neo-intima formation within vascular stents is responsible for this new phenomenon. We report the case of a 48-year-old man who underwent coronary irradiation therapy after stent placement in a de-novo/restenotic lesion. Despite an explicit recommendation of a combined anti-aggregatory therapy consisting of ticlopidine and acetysalicylic acid for at least 6 months, ticlopidine was withdrawn after 4 weeks. Two weeks later, the patient was readmitted to an external hospital with an acute myocardial infarction and successfully treated with thrombolysis. The angiographic and intravascular control, which was conducted after another two weeks, showed absolutely no neointima formation within the implanted stent. Thus, a late thrombotic occlusion of the implanted stent appears most likely to be the cause underlying the myocardial infarction. This case underlines, together with other existing reports, the importance of a prolonged, combined anti-aggregatory therapy after stent placement and subsequent intracoronary irradiation.

Rapid progress in the understanding and treatment of unstable angina and acute coronary syndrome are prompting occasional revisions to current treatment guidelines. The recommendations contained in this paper are based on the consensus reached during discussions at the 'International Cardiology Forum' in September 1998. Consensus was reached on significant major points, although some aspects remain controversial. A substantial body of data accumulated in a host of studies justify changes to current treatment habits.

The interpretation of three-dimensional (3D) structures of the coronary tree and the myocardium by a clinician demands a subjective visual integration of two-dimensional (2D) images of cardiac diagnostic procedures like coronary angiography and myocardial scintigraphy. Although in the conventional analysis of 2D display scintigraphic myocardial perfusion segments are arbitrarily assigned to three major coronary artery systems, the standard myocardial perfusion distribution territories correspond with the individual pathologic-anatomic coronary tree in only 50-60% of the patients. Hence, the mental integration of both 2D images of coronary angiography and myocardial scintigraphy does not necessarily allow an accurate assignment of particular myocardial perfusion regions to the corresponding vessels. For an objective assignment of each vessel segment of the coronary tree to the corresponding myocardial regions, we have developed a 3D "fusion image" technique and applied it to patients with coronary artery disease. Cause-and-effect relationships may be more obvious with 3D data fusion and may enable an easier comparison of anatomy and physiology. Preliminary results demonstrate that our newly developed 3D fusion image is useful for accurate assignment of coronary vessel segments to the corresponding myocardial perfusion regions and suggest that it may allow the clinician a comprehensive and accurate assessment of the patient's myocardial status.

Background: A fractional flow reserve (FFRmyo) < 0.75 is a well validated parameter for significance of coronary stenoses in cases of normal myocardial function. We used the FFRmyo limit in patients with impaired myocardial perfusion by myocardial infarction and/or hypertension for intermediate stenoses of the LAD for decision to PTCA and checked the indication by clinical follow-up., Methods: In 20 pts (5 women) with chest pain and visual 50 D% LAD stenoses, the FFRmyo was obtained by using a RADI-Pressure-Wire, the CFR by a densitometric technique (HODGSON), and the geometry of stenosis (minimal lumen diameter and diameter stenosis) by quantitative coronary angiography (QCA). EF and the kinetics of the anterolateral wall (expressed as radial shortening fraction) were measured by laevography., Results: The mean age of our 20 pts. was 59.4 years: 13 of the pts. (65%) had a history of hypertension, 9 (45%) pts. a history of myocardial infarction. The mean diameter stenosis was 50.8%. The mean value of CFR was 2.9. The FFRmyo ranged from 0.66 to 0.90, the mean value was 0.78. The 12 pts. with FFRmyo > or = 0.75 (60%, group A) were treated with the usual anti-anginal medications. A PTCA was performed only in patients with FFRmyo < 0.75 (N = 8 (40%), group B). Except for one pt. with instent restenosis, in the 7 pts. with denovo stenoses stent implantation was performed. Significant differences between the groups A and B were seen only for the total number of myocardial infarctions (8/12 vs. 1/8) and diameter stenosis (48.5% vs. 54.3%). All lesions of group B had a diameter stenosis of 50% or higher. CFR correlated significantly with the radial shortening fraction (r = 0.75), minimal lumen diameter (r = -0.51) and diameter stenosis (r = -0.46). FFRmyo correlated with diameter stenosis (r = -0.47) only. All pts. treated with PTCA were primarily free of pain or reduced angina at least 1 CCS stage; only one developed an angina due to a restenosis (74 D%) 2 months after PTCA and stent implantation. The pts. of group A did not get worse, nor were they readmitted within 6 to 13 months after catheterization., Conclusions: Pts. with 50 D% stenoses, impaired myocardial perfusion and FFRmyo < 0.75 had a good long-term benefit concerning clinical and angiographic result. No pts. with FFRmyo < 0.75 had a D% lower than 50; therefore, the PTCA of intermediate stenoses without quantification must be avoided. CFR is not helpful for a decision to PTCA in such cases, because a normal value of CFR is relevant only.

Supravalvular aortic stenosis is a rare cause of left ventricular outflow obstruction in adults. It occurs as an isolated defect sporadically or on a hereditary basis with an autosomal dominant trait without further phenotypical anomalies, or as part of the Williams syndrome with mental retardation and multiple other anomalies. This lesion was proved to result from a defect of the elastin coding gene. Supravalvular aortic stenosis is frequently associated with cardiovascular defects, particularly of the peripheral pulmonary arteries, thoracic aorta, carotid, subclavian, and coronary arteries and the aortic valve. The coronary arteries are subject to an increased perfusion pressure leading to dilatation, tortuosity and accelerated arteriosclerosis. We give details of a 35-year-old patient in whom a previously asymptomatic supravalvular aortic stenosis is associated with an excessive dilatation of the right coronary artery and the left anterior descending coronary artery as well as an ostium stenosis of the left common carotid artery. The patient did not present any phenotypical anomalies of the Williams syndrome.

In recent years, evaluation of cardiac autonomic activity by means of heart rate variability (HRV) determination and baroreflex sensitivity (BRS) testing has become readily available. The results of the ATRAMI (Autonomic Tone and Reflexes After Myocardial Infarction) study showed that both diminished HRV and baro-reflex sensitivity are associated with poor outcome in patients after myocardial infarction. In contrast to patients with coronary disease little information is available concerning cardiac autonomic activity in idiopathic dilated cardiomyopathy (IDC). Therefore, HRV and BRS were assessed in 160 patients with IDC and preserved sinus rhythm in order to investigate the relationship between HRV, BRS, and left ventricular ejection fraction. Time domain indices of HRV were computed from 24-hour digital Holter recordings. BRS testing was performed using the noninvasive phenylephrine method. Mean standard deviation of all normal RR intervals (SDNN) of the whole study population was 112 +/- 46 ms. A well preserved HRV (SDNN > 105 ms) was found in 74 patients (46%), a moderately decreased HRV (SDNN 70-105 ms) in 59 patients (37%), and a severely decreased HRV (SDNN < 70 ms) in 27 patients (17%). Mean BRS was 7.5 +/- 5.0 ms/mm Hg. A well preserved BRS (> 6 ms/mm Hg) was present in 78 patients (57%), a moderately decreased BRS (3-6 ms/mm Hg) was present in 38 patients (28%), and a severely decreased BRS (< 3 ms/mm Hg) in 21 patients (15%). There was only a weak correlation between SDNN and BRS (r = 0.19; p < 0.05). A weak correlation was found for SDNN and left ventricular ejection fraction (r = 0.29; p < 0.05). There was no significant correlation between BRS and left ventricular ejection fraction (r = 0.14). In summary, there was only a weak correlation between the HRV, BRS, and left ventricular ejection fraction in patients with IDC suggesting that these 3 variables may be independent predictors of sudden death in IDC. The relative prognostic value of these variables and other potential risk predictors including the presence of arrhythmias on Holter, microvolt T wave alternans, QTc dispersion, and signal-averaged ECG is currently under investigation in a large prospective observational study (Marburg Cardiomyopathy Study (MACAS)) during 5-year follow-up at our institution.

The hallmark of ischemic heart disease is the presence of focal obstructions in the major coronary arteries. Classically, epicardial stenoses are thought to exert their pathogenetic role mainly through a limitation on maximal flow capacity in the distal vascular bed. Ischemia is thus thought to occur whenever oxygen consumption exceeds the flow availability. Although a number of experimental studies confirmed these assumptions, the adherence of this experimental model with the clinical observations is still far from being convincing. Evidence now exists that atherosclerosis causes more profound alterations in the regulation of myocardial perfusion, besides the hydraulic effects of epicardial obstructions. These alterations affect endothelial regulation of coronary vasomotor tone both in the large arteries and in the distal microcirculation. In agreement with this experimental evidence, an abnormal response to endothelium-mediated vasodilators has been reported in patients with coronary artery disease. Moreover, several studies also reported an abnormal response of atherosclerotic coronary microcirculation to atrial pacing tachycardia and dipyridamole, which are thought to be largely endothelium independent. An even more striking observation is the finding of an intense microvascular constrictor response in the myocardium, supplied by a severely stenotic coronary artery, to pacing-induced ischemia. This observation strongly suggests that coronary microcirculation might aggravate the flow reduction imposed by the epicardial stenosis, thus playing some role in the pathogenesis of ischemia. This phenomenon might reflect the presence of a primary abnormality of coronary microcirculation in patients with coronary artery disease or the existence of a pressure-oriented regulation of vascular tone which prevent trans-stenotic pressure drop by means of a heterogeneously distributed microcirculatory vasoconstriction.

Magnetic resonance imaging (MRI) has become a well-established method for the diagnosis of diseases of the heart and the great vessels. Almost 20% of all patients cannot be completely examined by transthoracic echocardiography. In this patient group, MRI can be used as a second line technique to provide important diagnostic information not obtainable by echocardiography. However, there are clinical problems for which MRI may be used as the first line technique such as complex congenital heart disease, diseases of the great vessels, pericardial disease or cardiac tumors. MRI is undergoing rapid technical improvement and this will further improve the diagnostic utility of the technique, especially in patients with coronary artery disease.

The endothelium plays a crucial role in the process of atherosclerotic disease by its regulatory functions on the vasculature, such as control of vasomotor tone, local hemostasis and proliferative processes. Dysfunction of endothelial vasoreactivity contributes to reduced myocardial blood supply and, therefore, might promote myocardial ischemia. To control vasomotor tone, the endothelium releases a variety of substances such as prostacyclin, hyperpolarizing factor, endothelin and, most importantly, nitric oxide (NO). Endothelium-dependent vasodilation is impaired in patients with environmental or genetic risk factors for atherosclerotic disease, such as hypercholesterolemia, mainly due to increased oxidative stress produced by superoxide anions, which rapidly inactivate nitric oxide. Experimentally, an imbalance between nitric oxide and superoxide anions towards reduced nitric oxide bioavailability enhances migration of monocytes into the vessel wall and proliferation of smooth muscle cells. These oxidative processes, resembling a chronic inflammatory process, extending to the vessel wall, contribute to plaque architecture, e.g., by destabilization of fibrous caps. Indeed, long-term follow-up of patients with endothelial dysfunction demonstrated that impaired endothelium-dependent vasodilation is associated with increased cardiovascular event rates. Recent clinical data supported the role of endothelial dysfunction in patients with acute coronary syndrome and demonstrated a relation with elevated C-reactive protein levels, an unspecific marker of inflammation. Taken together, assessment of coronary endothelial vasoreactivity may serve as an index integrating the overall stress imposed by risk factors on the arterial wall and provides pivotal information, both as a diagnostic and prognostic tool in patients at risk for coronary heart disease.

Magnetic resonance imaging of the coronary arteries is difficult due to the tortuous course of these vessels, their small diameter, and their rapid movement caused by respiration and cardiac contraction. Initial investigations could demonstrate the feasibility of non-invasive magnetic resonance coronary angiography using 2-dimensional turbo-FLASH gradient-echo sequences in repeated breathholds of approximately 16 heart beats duration. Further developments, especially the design of navigator-echo-based respiratory gated 3-dimensional imaging sequences, permitted the acquisition of contiguous volume data sets of the heart which eliminated many limitations of 2-dimensional repeated breathhold sequences. With a spatial resolution of approximately 1.2 x 1.2 x 2 mm and a temporal resolution of approximately 126 ms, several authors reported sensitivities of 70-80% and specificities of approximately 90% for the detection of coronary artery stenoses. Further improvements can be expected from new, intravascular contrast agents and from ultrafast sequences which permit acquisition of a sufficiently large imaging volume within one single breathold.

Patients with recurrent syncope undiagnosed after extensive noninvasive and invasive testing pose a diagnostic and therapeutic dilemma. Holter monitoring is non-diagnostic in 90% of cases. Recent developments in loop recorder technology permit longterm ECG monitoring in patients with recurrent unexplained syncope. The implantable loop recorder monitors a single lead electrogram continuously using 2 sensing electrodes on the device shell. The device was implanted in 20 patients (11 male, 9 female) with the history of recurrent syncope. During a mean follow-up of 12+/-6 months after device implantation, 11 patients (55%) experienced syncope (8 pts) or presyncope (3 pts). In the remaining 9 patients, no syncope occurred. In all 11 patients with syncope or presyncope during follow-up, loop recording definitively determined whether an arrhythmia was the cause of symptoms or not. Diagnosis included bradycardia in one patient, tachycardia in two patients, in one patient two rhythm disturbances were revealed: frequent ventricular premature beats with bigemini and atrial flutter. Two patients had a neurocardiogenic syncope. Syncope was nonarrhythmic in 5 patients. An implantable loop recorder is useful for establishing the diagnosis if symptoms are recurrent but too infrequent for conventional monitoring techniques.

Unlabelled: Stress echocardiography has been shown to be a valuable noninvasive method for the diagnosis of restenosis after coronary angioplasty. To determine the usefulness of dobutamine stress echocardiography (DSE) for assessment of restenosis after intracoronary stent implantation, we studied 50 patients (59+/-10 years; 1-vessel disease, n=16; multivessel disease, n=34) after stent implantation. After 6 month, both DSE (5-40 mcg/kg/min, 0-1mg atropine) and angiography were performed within 48 hours and evaluated in a blinded fashion. Restenosis was defined by quantitative coronary angiography as minimal lumen diameter (LD) <50% of average reference LD. Diagnostic criteria of DSE were new or worsening wall motion abnormalities in corresponding perfusion territories during stress. Angiography revealed restenosis in 8 patients; one patient had a denovostenosis distal to the stented segment (8 x left anterior descending artery, 1 ACVB to the right coronary artery). In 6 of these 9 patients, DSE was positive (mean reduction of LD 88+/-7%; sensitivity 67%), in 3 patients negative (mean reduction of LD 62+/-7%, 1 x termination of DSE because of wall motion abnormalities in an area not supplied by the stented vessel). In 38 of 41 patients without restenosis, DSE showed no stress-induced wall motion abnormalities in the LV area supplied by the stented vessel (specificity 93%)., Conclusions: DSE is a useful noninvasive method for detecting restenosis after intracoronary stent implantation. With negative DSE at follow-up, a functionally relevant stent restenosis is highly unlikely.

The analysis of wall motion abnormalities with dobutamine stress echocardiography is an established method for the detection of myocardial ischemia. With ultrafast magnetic resonance tomography, the application of identical stress protocols as used for echocardiography is possible. In 208 consecutive patients (147 M, 61 F) with suspected coronary artery disease, dobutamine stress echocardiography partially using harmonic imaging and dobutamine stress magnetic resonance tomography (DSMR) were performed prior to cardiac catheterization. DSMR images were acquired during short breath holds in 3 short axis-, a 4-, and a 2-chamber view using a turbo gradient echo technique. Patients were examined at rest and during a standard dobutamine-atropine scheme until submaximal heart rate was reached. Regional wall motion was assessed in a 16 segment model. Significant coronary heart disease was defined as angiographic >/=50% diameter stenosis. With DSMR, significantly more patients yielded very good (69%) or good (13%) image quality in comparison with dobutamine stress echocardiography (20% and 31%, p<0. 05). Moderate image quality occurred in 16% with MR and 41% with dobutamine stress echocardiography (p<0.05), 2% and 8% were non-diagnostic. With each technique 18 patients could not be examined (DSE: emphysema: 10, adipositas: 8, DSMR: claustrophobia: 11, adipositas: 6, contraindication: 1). Four patients did not reach target heart rate. In 107 patients, significant coronary artery disease was found. With DSMR sensitivity was 88.7% (dobutamine stress echocardiography: 74.3%; p<0.05) and specificity 85.7% (dobutamine stress echocardiography: 69.8%; p <0.05). This difference was most pronounced in the group with moderate echocardiographic image quality. High dose DSMR is superior to dobutamine stress echocardiography and can replace this technique especially in patients with moderate echocardiographic image quality.

Despite considerable progress in the knowledge about pathophysiology of cardiac allograft vascular disease (CAVD), only few systematic studies are available, characterizing the natural course during long-term follow-up after heart transplantation (HTX). Therefore, we analyzed in 354 heart transplant recipients (305 male, 45.9 +/- 11.2 years, mean observation period 5.8 +/- 3.0 years, range 0.9-12.4 years) the results of 1129 coronary angiograms under the aspects of development, severity, localization, and progression of disease related to the prognosis of patients. As expected an increasing prevalence was found over time with a luminal obstruction > or = 30% in 83% of all patients more than 10 years after HTX. Coronary artery stenosis (> or = 50%) at initial diagnosis was predominantly localized in the LAD (46%) followed by RCX (31%) and RCA (23%). Angiographic risk profiles with an impaired prognosis could be identified in the form of an early development (< 4 years post HTX) of disease (p = 0.03), luminal obstruction > 50% (p = 0.001), and multivessel appearance at first diagnosis (p = 0.02) as well as in progressive forms of CAVD (p = 0.001). Summarizing, CAVD is a frequent finding in HTX recipients. Especially in patients with early onset, progressive, and advanced stages of disease it represents a prognostically limiting complication following HTX. Identification of the natural course is of major importance defining the need and efficacy of future palliative therapeutical approaches.

The number of heart catheter laboratories in Germany has been increasing for years. While there are general training regulations for cardiologists, nothing comparable exists for the assistant staff in interventional cardiology. Qualification is settled within the department. Aim of this study was the determination of the demand in general training and qualification courses. All heart catheter laboratories in North Rhine-Westphalia were questioned. Assistants (227) and medical directors (43) from 48 laboratories (54.0% returns) answered. Of the assistants 59.1% were qualified nurses, 28.2% consulting room assistants, and 10.1% medical technicians. Most of them were female (85.0%); the average age was 34.3 years. Of the assistants 73.1% were not trained in their current hospital or practice. Before their occupation in cardiac catheterization, 51.8% worked in nursing and 17.6% in ECG, sonography, etc. None of the 227 assistants was still in training at the time of questioning although 68.3% of the hospitals and practices accept trainees. Nine out of ten laboratories offer inhouse qualification, mainly in radiation protection (82.1%) and medical fields (66.7%), and 85.3% of the assistants have already attended these. Of the medical directors 90.0% and 99.2% of the assistants consider general training and qualification courses to be necessary. When asked for important fields for training programs, the assistant staff mentions "medicine" (77.6%), "examination assistance" (67.0%), and "EDP" (60.4%), while the medical directors place importance on "quality management" (89.2%) and "radiation protection" (86.5%). The job market for assistants the interventional cardiology is still good: 14.3% of the laboratories plan to take on new employees, 61.9% want to keep their number of assistants. The share of part-time work is low (16.8%). The momentary qualification and training of assistant staff in interventional cardiology does not match the demand. General programs for trainees with universally applicable teaching objectives and examination regulations are necessary.

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.

Mönckeberg's disease (MD) is characterized by media calcinosis (MC) of the arteries of the lower extremities. MC is distinct from atherosclerosis, occurs in different vascular beds, and its etiology is unknown. Here, we report a case of a 46-year old male with no prior medical history of cardiovascular disease, no metabolic risk factors, and normal laboratory findings, who presented with accidental findings of marked diffuse calcifications along the entire course of the femoral superficial and profunda arteries on plain x-ray films. Follow-up cardiovascular diagnostics using high resolution B-mode ultrasonography, ultrafast CT, and x-ray angiography revealed extensive abluminal arterial wall calcification without evidence for premature or advanced intima-related atherosclerosis in the abdominal aorta, in the arteries of the pelvis, and the lower extremities. Calcifications were also present in the proximal segments of the circumflex and left anterior descending coronary arteries. The carotid arteries showed no calcium deposits. This observation confirms that MC may occur in the absence of secondary risk factors (primary MC) and independently of atherosclerosis. Simultaneous involvement of several vascular territories including the coronary arteries appears possible. The systemic character of primary MC is consistent with a genetical cause of this as yet poorly defined disease.

Reports from several countries indicate that women are disadvantaged in the treatment of coronary heart disease. The aim of the present review is to examine--on the basis of current population-based data (National Health Survey [NHS], hospital diagnosis registry, mortality rates)--whether in the Federal Republic of Germany more recently a change in favor of women could be established. According to NHS results prevalence rates of hypertension, overweight, and smoking in men exceed those of women, whereas hypercholesterolaemia is equally prevalent in both sexes. From 1984/85 to 1990/91 the NHS revealed a marked decline of smoking in men, and a parallel increase in women. The prevalence of chest pain shows no gender difference, but chest pain in men is more predictive for coronary artery disease. In acute myocardial infarction [AMI] thrombolysis and PTCA are applied with equal frequency; the average length of stay in hospital is greater for women. Coronary bypass surgery and rehabilitation in hospitals are less frequently applied in women. Little is known about gender differences in psychosocial adaptation after AMI. AMI mortality rates in all age groups are lower in women, and their mean age of death is higher. However, the decline of AMI mortality since 1980 was less pronounced in women compared to men.

The presented case report describes lifethreatening complications of pharmacological stress echocardiography with dobutamine. A 66-year old male suffered an acute anterior wall myocardial infarction during dobutamine atropine stress echocardiography. Symptoms and signs of myocardial infarction developed after maximal dobutamine-dose (40 micrograms/kg/min) and the additional application of atropine. Emergency coronary angiography revealed extensive coronary artery disease with proximal occlusion of the left anterior descending artery which was successfully recanalized. In a second patient ventricular fibrillation echocardiography and electrocardiographic signs of acute myocardial ischemia developed after high-dose dobutamine stress and required prolonged resuscitation. The possible mechanisms, incidence and risk of acute myocardial ischemia during dobutamine-atropine stress are discussed and compared to bicycle ergometry. The presented life threatening complications of dobutamine-atropine stressechocardiography emphasize the important of available and adequate emergency facilities.

Respiratory gated MR coronary angiography is a new MR imaging technique which permits reconstruction of the coronary arteries from a three-dimensional data set obtained from contiguous parallel sections. In this study, respiratory gated MR angiography was applied to assess significant coronary artery stenoses (> or = 50%). MR imaging was performed in 68 patients (50 men, 18 women) who had been referred to cardiac catheterization because of suspected or known coronary artery disease. The evaluation of coronary artery stenoses was performed in a blinded manner in the proximal, middle, and distal vessel segments after multiplanar coronary reconstruction of the MR images. Of the 680 coronary segments, 275 (40%) were located outside the imaging volume and were, therefore, excluded from further analysis. The highest sensitivity for stenosis detection was found in the proximal left anterior descending (LAD) and right coronary artery (RCA) with 75% and 71%, respectively. The overall sensitivity, however, was low with 48%. The overall specificity was 92%. The positive and negative predictive values were 67% and 85%, respectively. This study shows that significant coronary artery stenoses, especially in the proximal LAD and RCA, can be correctly identified using respiratory gated MR angiography. However, further technical improvements are necessary before this method may become a reliable diagnostic tool in clinical practice.

The assessment of coronary flow reserve, defined as the ratio of hyperemic to resting coronary blood flow, allows a more functional analysis of the coronary vasculature in addition to coronary angiography. Three different kinds of cardiac catherization procedures for measurement of coronary flow reserve will be reviewed with respect to reliability, feasibility and clinical significance in the diagnosis and treatment of diseases of coronary conductance and resistive vessels: first, from the techniques utilizing selective catherization of coronary sinus, the thermodilution and the oxymetry have to be considered qualitatively rather than quantitatively because of a large variance and an underestimation of hyperemic blood flow responses. The gas chromatographic argon method provides a more quantitative rationale for the selective measurement of resting and hyperemic coronary flow, and thus to more exact differentiation between a reduced hyperemic vs an increased resting flow as a major cause of a reduced flow reserve. Furthermore, because of a reliable reproducibility this approach allows to proceed follow up studies to assess impact of therapeutic interventions on coronary flow reserve in individual patients. Second, angiographic methods utilize either densitometry or time-to-arrival measurements of defined boluses of contrast medium. The utility of the TIMI-frame count and of densitometric algorithms will be discussed. These methods offer the advantage of being rather easy to handle and to be performed within routine coronary angiography. However, they can be applied to a only rather small group of patients because of methodological limitations in patients with multivessel disease, with disturbed left ventricular function and with irregular heart rate. Third, this group comprises methods in which devices have to be advanced into coronary circulation such as pressure or doppler guide wires, which allows selective assessment of regional coronary flow and reserve. Currently evaluated approaches to assess significance of coronary stenosis will be discussed. In conclusion, currently different methods for the assessment of coronary flow reserve are available in cardiac catherization laboratories and each of these methods provides specific advantages and disadvantages, which have to be considered to select the appropriate approach for the diagnosis of functional disturbances of the coronary conductance and resistance vessels. The obtained functional data on coronary circulation should always be interpreted only in context with myocardial function and clinical symptoms of the individual patient.

A relation between myocardial ischemia and induction of ventricular arrhythmias can be demonstrated in patients with coronary heart disease--in contrast to patients with primary non ischemic cardiac diseases--using a combined metabolic-electrophysiological investigation protocol consisting of programmed atrial and ventricular stimulation with simultaneous measurement of the arterio/coronary venous difference for lactate, pyruvate, free fatty acids and amino acids. There are significant metabolic distinctions between both ischemic and non ischemic heart disease under pacing stress conditions as well as at rest. Areas of "hibernating myocardium" resp. "mismatch" zones in the myocardium showing reduced or abolished perfusion and preserved metabolism during scintographic SPECT/PET studies, may be found more often in patients with ventricular tachycardias (VT) or ventricular fibrillation (VF) in the chronic post myocardial infarction state than in patients without VT/VF. The proof of such zones may be considered a possible risk factor for arrhythmic events and sudden cardiac death after myocardial infarction. Hereby the concept of an interaction between acute and chronic ischemia triggering the onset of polymorphic VT or VF gaines increasing acceptance. In contrast, monomorphic reentrant VT are usually generated in the border zone of scarred areas where islands of vital fibers are surrounded by fibrotic tissue. These arrhythmogenic origin regions are characterized by a "match" pattern presenting a comparably severe reduction of perfusion and metabolism. Under those circumstances a control resp. suppression of the VT focus can only be provided by interventional techniques like catheter ablation, antitachycardiac surgery or implantation of a cardioverter/defibrillator beyond antiarrhythmic drug therapy. An antiischemic causal treatment (bypass surgery or angioplasty) represents for maximal 40% of patients with ischemically induced ventricular arrhythmias an adequate and sufficient therapeutic option. This pure antiischemic procedure seems to be justified especially in patients with preserved left ventricular function, proof of reversible ischemia and non inducibility of VT/VF following revascularization or non inducibility pre- and post intervention. In all other instances an additional treatment by antiarrhythmic drugs or preferably the implantable defibrillator is required.

During the last 25 years the internal thoracic artery has become a well established conduit for coronary revascularization. Next to angiography, duplex-sonography is increasingly used as a non-invasive imaging procedure for the evaluation of this graft vessel. Preoperative investigation in 117 patients has yielded a high level of agreement between angiography and duplex-sonography. While the preoperative flow-pattern is dominated by systolic flow as it is typical for vessels supplying skeletal muscle, the postoperative findings show an adaptation to the coronary vascular bed as the diastolic flow increases. These non-invasive measurements are well matched with invasive intravascular recordings. Coronary angiography and duplex-sonography of the internal thoracic artery yielded comparable findings in respect to the procedural result. Considering the increasing use of the internal thoracic artery in coronary artery bypass surgery, this non-invasive method should gain increasing relevance.