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Aim To assess intervendor agreement of cardiovascular magnetic resonance feature tracking (CMR-FT) and to study the impact of repeated measures on reproducibility. Materials and methods Ten healthy volunteers underwent cine imaging in short-axis orientation at rest and with dobutamine stimulation (10 and 20 μg/kg/min). All images were analysed three times using two types of software (TomTec, Unterschleissheim, Germany and Circle, cvi42, Calgary, Canada) to assess global left ventricular circumferential (Ecc) and radial (Err) strains and torsion. Differences in intra- and interobserver variability within and between software types were assessed based on single and averaged measurements (two and three repetitions with subsequent averaging of results, respectively) as determined by Bland–Altman analysis, intraclass correlation coefficients (ICC), and coefficient of variation (CoV). Results Myocardial strains and torsion significantly increased on dobutamine stimulation with both types of software (p, Highlights • This is the first comparison of two types of CMR-FT software resulting in clinically valuable inter-vendor agreement data. • Assessment of myocardial strain and torsion is feasible with both types of software at rest and with dobutamine stimulation. • For both vendors, Ecc qualifies as the most robust parameter with the lowest variability.

In order to determine the quality of different chromophores to form β-sheet model systems, this paper reports on the structure of the isolated amino acid Ac–Trp–OMe and its dimer. The amino acid is protected at the terminal positions by introducing an acetyl and an O-methyl group. Only one isomer with a linear β-sheet related structure is obtained for the monomer. In contrast to similar systems containing the Phe chromophore, no β-sheet model system is obtained for the dimer. Due to the presence of polar NH groups in the side-chain of the indole moiety the minimum energy structure of the dimer contains hydrogen bonds between the NH groups of indole and C=O groups of the backbone. The structures are derived from the frequencies obtained from IR/R2PI spectra applied both to the region of the N–H and C=O stretching vibrations and a theoretical approach including force field and ab initio calculations. The force field calculations are used to explore the various possibilities on the potential energy surfaces ...

A combined experimental and theoretical study on the structures and vibrations of 3- and 4-aminophenol in their neutral and ionic ground states is presented. The vibrations of the two possible isomers of 3-aminophenol and the one isomer of 4-aminophenol are investigated by mass analyzed threshold ionization (MATI) spectroscopy in the ionic ground state and by infrared resonant 2-photon ionization (IR/R2PI) spectroscopy in the neutral ground state. The experimentally observed vibrational frequencies of all isomers are in excellent agreement with the calculated values obtained by density functional theory (DFT) and at the complete active space self-consistent field (CASSCF) level of theory. The calculations support the assignment of different isomers. Furthermore, the experimentally observed ionization potentials are well predicted by CASMP2//CASSCF calculations.

A combined experimental and theoretical study on the structure of the dipeptide model Ac–Phe–NHMe and its dimer (Ac–Phe–NHMe)2 is presented. In order to get a detailed vibrational analysis of all functional groups which are relevant to analyse the different structural arrangements, IR/R2PI spectra are recorded in the regions of the NH and the CO stretching vibrations. Force field calculations are used to scan the complex conformational landscape both of Ac–Phe–NHMe and the dimer (Ac–Phe–NHMe)2. Subsequent ab initio and DFT calculations on the most stable structures lead to predictions of the cluster geometries and their vibrational frequencies. Three isomers of the Ac–Phe–NHMe monomer have been assigned which contain either a β-sheet related configuration or hydrogen-bonded structures. The most prominent species has a β-sheet related conformation. The observed dimer contains a doubly hydrogen-bonded arrangement and turns out to be a β-sheet model system. In contrast to the β-sheet model (Ac–Phe–OMe)2 a different structural arrangement is found, connecting “the outer” CO and NH groups.

In this paper the structures of the isolated tripeptide model Ac–Val–Tyr(Me)–NHMe (Val = valine, Tyr = tyrosine) and its cluster with water are investigated by mass-, isomer- and state-selective IR/UV double resonance spectroscopy. From the IR spectra both in the region of the NH and CO stretching vibrations and in combination with force field and ab initio calculations it can unambiguously be derived that the peptide contains a stretched, β-sheet related structure. Thus the peptide serves as an ideal candidate for β-sheet model systems. By adding one water molecule to the peptide the β-sheet related structure seems to be preserved with a water molecule being attached to the NHMe group.

In this paper we report on the structure of the isolated dipeptide Ac–Val–Phe–OMe (Val=valine, Phe=phenylalanine) which is protected at the terminal positions by introducing an acetyl and a methyl group. Both resonant two-photon ionization (R2PI) and IR/R2PI spectroscopy are applied. This is the first application of IR/R2PI spectroscopy to a dipeptide. Both the region of the C–H and N–H stretching vibrations as well as the region of the C=O stretching vibrations are investigated. The chosen dipeptide exhibits only one prominent conformer in the gas phase containing a “linear” non-hydrogen-bonded structure which is an ideal candidate for a β-sheet model.

In this paper we report on the structure of isolated clusters formed by the protected amino acid Ac-Phe-OMe and pyrazole or 5-methyl-3-aminopyrazole (MAP). Ac-Phe-OMe contains phenylalanine (Phe) which is protected at the terminal positions by introducing an acetyl and a methyl group. From our previous gas phase investigations it is known that the conformation of Ac-Phe-OMe is similar to the one of an amino acid in a β-sheet structure. Experimental studies in the liquid phase show that pyrazole derivatives are suitable agents to form very stable aggregates with β-sheet model peptides in order to prevent an aggregation with other peptide molecules. The structures of the Ac-Phe-OMe/(pyrazole, MAP) clusters are investigated by applying Resonant 2-Photon Ionization (R2PI) and infrared/R2PI spectroscopy as well as Hartree-Fock and DFT calculations. Different structural arrangements of the clusters are discussed. In the case of MAP at least two different isomers are observed experimentally.

We report on the structure of phenylalanine which is protected at the terminal positions by introducing an acetyl and a methyl group (Ac–Phe–OMe). The structures of Ac–Phe–OMe and its dimer are investigated by applying resonant 2-photon ionization (R2PI) and IR/R2PI spectroscopy as well as Hartree-Fock and density functional theory (DFT) calculations. In contrast to the R2PI spectrum of unprotected phenylalanine the spectrum of Ac–Phe–OMe exhibits only one prominent isomer. The geometry of this isomer can be correlated with a β-sheet related structure. In the case of (Ac–Phe–OMe)2 only hydrogen-bonded NH groups are observed, indicating a dimer which can easily be formed by two monomers building a β-sheet model system. This is the first observation of such a model system in the gas phase.

In this Letter, we report on the application of infrared/photo induced Rydberg ionisation (IR/PIRI) spectroscopy to the hydrogen-bonded phenol(H2O)1+ cluster yielding the frequency of the symmetric OH stretching vibration of the bare cluster ion. By comparing IR/PIRI and IR-photodissociation spectra the symmetric OH stretching mode of the water moiety turns out to be a localised uncoupled vibration. Furthermore, CASSCF calculations for the phenolic OH stretching vibration of phenol(H2O)1 in the S 0 , S 1 , and D0 states are performed by using a very large active space including σ- and π-orbitals. These calculations yield OH stretching frequencies which are in good agreement with the experimentally observed vibrational frequencies of the S0 and S1 states. The OH stretching vibration of the D0 state is predicted to be lower than 2800 cm−1.

The IR double-resonance techniques IR/R2PI (infrared/resonant 2-photon ionization), IR/PIRI (infrared-photo-induced Rydberg ionization) and IR-photodissociation spectroscopy are valuable tools to investigate structure, vibrations, and dynamical processes of neutral and ionic hydrogen-bonded clusters containing aromatic molecules. In this paper we report on the application of the IR double-resonance techniques to determine the NH and OH stretching vibrations of 4-aminophenol and 4-aminophenol(H2O)1, both in the neutral (S0) and ionic (D0) ground state. All vibrational frequencies obtained for 4-aminophenol and the cluster are compared with the values obtained from ab initio and DFT calculations. In the S0 state, a trans-linear arrangement of 4-aminophenol(H2O)1 is obtained containing an O-H·· O hydrogen bond. In the D0 state an overlay of two spectra can be observed resulting from the trans-linear structure and a second structure which contains a N-H·· O hydrogen bond. The observation of these two structures within the ion is an interesting example of a rearrangement reaction in the ionic state.

In this paper we report on the application of infrared/photoinduced Rydberg ionization (IR/PIRI) and IR-photodissociation spectroscopy to investigate the CH, NH or OH stretching vibrations of indole+ and the indole(H2O)1+ cluster cation. All vibrational frequencies of indole+ and indole(H2O)1+ are compared with the values obtained from ab initio calculations. In the case of the indole+ cation the NH vibration is observed. This is the first observation of a NH vibration in a bare cation. For indole(H2O)1+ a hydrogen-bonded structure with a nearly linear hydrogen bond can be derived both from ab initio calculations and the IR-spectra. By applying the state selective IR/PIRI spectroscopy to indole(H2O)1+, no vibrational couplings between the intermolecular O–H⋯N stretching vibration and the intramolecular OH stretching modes of the water moiety are observed. In the IR-photodissociation spectra of indole(H2O)1+ the NH, OH, and CH stretching vibrations as well as overtones of bending modes are observed. In agr...

Recurrent syncopes in a 68 year old patient prompted further examination in addition to a neurological check. Holter monitoring was performed without antiarrhythmic medication. The ECG showed accelerated polymorphic ventricular tachycardias with degeneration to ventricular flutter and spontaneous termination (left). The tachycardias were documented twice and were sustained for up to …

HISTORY AND CLINICAL FINDINGS A 29-year-old female was admitted with the diagnosis of multiple deep vein thrombosis of the upper limbs and neck and pneumonia secondary to pulmonary embolism on the right side. Medical history revealed that in vitro fertilization with hormone stimulation had been carried out 5 weeks before. For ten days the patient had noticed a growing, painful swelling on the right side of her neck accompanied by difficulties in swallowing. Since this time she had experienced episodes of shortness of breath without chest pain. Clinical findings showed a soft and slightly painful swelling of the right side of the neck without dyspnoea or cyanosis at rest. Breath sounds were decreased over the right lower lung on auscultation. INVESTIGATIONS Magnetic resonance imaging (MRI) confirmed complete obstruction of the subclavian and brachiocephalic vein on the right side and clots in the superior vena cava, left subclavian vein, bilateral internal jugular veins and the right axillar vein. Chest x-ray showed pleural effusion on the right side. TREATMENT AND COURSE As the seven-week pregnancy was found not to be viable anymore, fibinolysis with streptokinase was started under protection of a temporary cava filter. During the following hours the patient developed serious bleeding as a complication of this therapy and fibrinolysis had to be discontinued after 16 hours. In subsequent examinations the obstruction of the left internal jugular vein was unchanged but collaterals around the obstruction were noticed. The other veins affected were open, some with reduced flow. Several risk factors were found in the history of the patient such as smoking, immobilization, a positive family history, protein S deficiency and APC resistance. After 3 weeks of hospital therapy the patient was discharged under oral anticoagulation with coumarin. CONCLUSION In vitro fertilization with hormonal stimulation may cause serious complications in patients with unknown coagulation disorders or with an ovarian hyperstimulation syndrome. Risk factors for thromboembolism need to be ruled out carefully before starting the procedure.

The structures of neutral catechol, catechol(H2O)1, and catechol(H2O)3 are investigated by IR/R2PI spectroscopy and ab initio calculations at the HF and MP2 level of theory. Furthermore, the structure of the ionic catechol(H2O)1+ cluster is derived from resonant IR-photodissociation spectroscopy as well as ab initio calculations. Trans-linear arrangements are obtained for the neutral (S0) and ionic (D0) ground state of the catechol(H2O)1 cluster. In the case of the neutral catechol(H2O)3 cluster (S0 state) a cyclic and a π-bonded structure are discussed which are of similar stability. From the IR spectrum of catechol(H2O)3 it can be derived that the cyclic structure is the most probable arrangement. The calculated OH stretching frequencies of this structure are in good agreement with the experimentally observed values.

In this paper structures of resorcinol (1,3-dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene) cations are presented. The adiabatic ionization potentials of the dihydroxybenzenes and the vibrations of the ionic ground state of the dihydroxybenzene cations are experimentally obtained by mass analyzed threshold ionization (MATI) and infrared photoinduced Rydberg ionization (IR-PIRI) spectroscopy. In contrast to the catechol (1,2-dihydroxybenzene) cation, two isomers of different symmetry can be obtained for resorcinol and hydroquinone cations. The MATI and IR-PIRI spectra of the isomers of resorcinol will be interpreted by comparing the experimental results with the results of density functional theory (DFT) and ab initio calculations performed at the complete active space self-consistent field (CASSCF) level of theory. Furthermore, the adiabatic ionization potentials as well as the excitation energies (for the S1←S0 transition of neutral dihydroxybenzenes) are derived from CASSCF calculations for th...

This Letter presents a new technique (IR/PIRI) to investigate OH stretching vibrations of cations. In the IR/PIRI technique the MATI signals obtained for the electronic origin or a vibrational state of the ion are depleted by an IR laser if the frequency of the IR laser is in resonance with an OH stretching vibration of the cation. As an example, the resorcinol molecule is chosen. Two different isomers of this molecule are investigated. In combination with ab initio calculations and IR depletion spectroscopy performed for the electronic ground (S 0 ) and electronically excited state (S 1 ) of the neutral molecule all OH stretching vibrations of the different isomers in the S 0 , S 1 , and D 0 states are interpreted.

To determine structure and vibrations of catechol and d2-catechol (C 6 H 4 (OD) 2 ) in the ionic ground state, MATI spectra as well as ab initio and DFT calculations are presented. The comparison of the experimentally observed vibrational frequencies with the calculated values leads to a complete assignment of all vibrations. CASSCF and DFT calculations predict a planar geometry of catechol in the S 0 and D 0 states. CASSCF calculations for the S 1 state show that the free OH group of catechol is rotated out of the plane of the aromatic ring by ∼24°. This calculation supports the assumptions of earlier experimental work. The adiabatic excitation energies (S 1 ←S 0 ) and the adiabatic ionization potentials of catechol and its deuterated isotopomer can be predicted by CASSCF calculations including zero-point energies and MP2 corrections.

In this communication the first IR/R2PI (infrared/resonant two-photon ionisation) spectra of CO stretching vibrations are presented applied to a β-sheet model system. CO vibrations are extremely important to describe the structure of isolated peptides and especially the hydrogen bonding in β-sheet related structures in the gas phase.

Oxygen free radicals have been shown to play a major role in the development of perfusion abnormalities, contractile dysfunction, and irreversible injury in ischemic-reperfused myocardium. The aim of this study was to assess the direct protective effects of radical scavengers, calcium antagonists, and combination of these substances against free radical induced myocyte damage. Viability (% of rod-shaped cells) and adenine nucleotide content (AdN, high-pressure liquid chromatography) of isolated adult rat cardiomyocytes were measured after exposure to hypoxanthine (2 mM) and xanthine oxidase (25 mU/ml). After 90 min, viability of myocytes decreased to 4.2 +/- 3.4% (mean +/- SEM) of pre-exposure control, and AdN decreased from 28.2 +/- 1.8 to 8.09 +/- 1.1 nmol/mg protein. Addition of catalase (1500 U/ml) resulted in the preservation of viability (77 +/- 6% of pre-exposure control, n = 6, mean +/- SEM), and AdN 84 +/- 6%, p less than 0.001. These values are not significantly different from those measured in myocytes not exposed to free radicals (88 +/- 9% and 79 +/- 6%, respectively). Superoxide dismutase (2400 U/ml), dimethylthiourea (10 mM), and desferrioxamine (1 mM) did not preserve either viability or AdN. The calcium antagonist verapamil (10 microM) also preserved myocyte viability significantly (23 +/- 9.7%, p less than 0.05 vs unprotected cells), but failed to prevent the loss of AdN (13.2 +/- 4%, not significant as compared to unprotected cells). Viability and AdN in myocytes treated with nifedipine (10 microM) or diltiazem (10 microM) were not higher than in unprotected cells. All combined treatment forms which included catalase resulted in the preservation of myocyte viability as well as AdN. These data show that only the hydrogen peroxide scavenger catalase protects isolated cardiomyocytes against free radicals generated in the purine catabolic pathway.

Automatic atrial anti-tachy pacing (aATP) is a novel approach to treat paroxysmal/persistent atrial tachyarrhythmias in pacemaker patients. To evaluate the efficacy of aATP in terminating spontaneous atrial flutter/tachycardia episodes (AT), a dual-chamber stimulator with extensive diagnostic capabilities and programmable aATP therapies (AT500(TM), Medtronic Inc.) was implanted in 30 patients with conventional pacing indications. During a mean follow-up time of 5.5 (1-12) months, aATP was delivered for 10494 AT. According to automatic device analysis, 8289 AT were treated with success (success-rate 79.0%). On 468 AT stored with the corresponding atrial EGM, an additional manual analysis was performed. The success-rate based on automatic analysis of these AT episodes (73.1%) was comparable to that found for all treated AT (79.0%), but manual EGM analysis revealed that only 209 of the 468 treated AT episodes (44.7%) were actually terminated by aATP. The aATP success-rate in the slower (cycle length 360-270 ms) AT detection zone was significantly higher (73.8%, 62/84 eps) than in the overlapping, faster (cycle length 270-220 ms) AT zone (38.3%, 147/384 eps, P0.01).According to manual analysis, 1. aATP was safe and had a success-rate of 44.7%, 2. aATP success-rate was higher for AT in the slower than in the faster detection zone and 3. automatic analysis overestimated the efficacy of aATP.

A 21-year-old woman with known endocardial fibroelastosis diagnosed when aged 3 months was admitted because of progressive dyspnoea. The physical examination revealed symptoms of heart failure, with pulmonary rales, mild hepatomegaly, and tachyarrhythmia.The electrocardiogram showed atrial fibrillation, complete right bundle branch block and right ventricular hypertrophy. Echocardiography indicated hypertrophy and dilatation of the right ventricle (61 mm) with tricuspid regurgitation and hypoplasia of the left ventricle. Heart catheterization confirmed pulmonary hypertension (60/46 mmHg) as well as dilatation and hypokinesia of the right ventricle. Right ventricular biopsy showed severe myocardial hypertrophy resulting from secondary pulmonary hypertension, while no evidence of myocarditis or idiopathic dilated cardiomyopathy was found.Symptoms of heart failure improved under medical treatment with digitalis, angiotensin-converting enzyme inhibitor and diuretics.Primary endocardial fibroelastosis of the contracted type must be included in the differential diagnosis of heart failure occurring in young adults.

We report the case of a 69 year old patient, who underwent transvenous implantable cardioverter defibrillator (ICD) device change (Medtronic GEM VR 7227 Cx Active Can) because the ICD reached its replacement indicators. Preoperative chest X-ray and intraoperative defibrillation threshold tests and high voltage impedance did not show lead fracture of the five year old lead (Transvene 6936-65). At the second postoperative day the alarm of the newly implanted ICD device was activated because of high impedance in the painless lead impedance measurement (PLI) and the lead was replaced. The explanted lead showed a fracture detectable only by PLI.

The discrimination of supraventricular versus ventricular tachycardias by an implantable cardioverter-defibrillator (ICD) is still a remaining clinical problem. The false positive detection of supraventricular as ventricular tachycardias causes inadequate electrical therapies of the ICD. To improve the increase of specificity criterias like "Onset" or "Stability" are offered. If these criterias during tachycardia are not fulfilled, the "sustained rate duration" (SRD) is offered as a security criterion. The SRD reasons the delivery of the therapy during tachycardia after a programmable time. Aim of the study was to evaluate, if SRD in patients with known arrhythmia absoluta (AA) in atrial fibrillation and programmed "Onset"/"Stability" increases the sensitivity without loss of specificity in the treatment of hemodynamically tolerated ventricular tachycardias and which programming should be chosen. Our patient collective included 274 patients (pts) with new implanted ICD of the third generation. In 39 (14%) pts AA was known in the medical history. From these 39 (100%) pts, 18 (46%) pts had known tachyarrhythmic episodes (group I) in the area of the ventricular tachycardia-zoneor = 160 beats per minute, whereas in 21 (54%) pts a tachyarrhythmia absoluta (TAA) was unknown (group II). During follow-up of 12 +/- 8 (2-26) months, 151 tachycardias occurred and could be classified as supraventricular tachycardias by stored electrograms. In 9/18 pts of group I, a TAA occurred during follow-up. The initial programmed SRD during first TAA was 62 +/- 39 (35-90) s and was prolonged to 135 +/- 64 (90-180) s. After this prolongation, no inadequate therapy was delivered. In group II, 19/21 (90%) were inadequately treated during TAA. The initial SRD-programming was 45 +/- 28 (0-90) s and was prolonged to 201 +/- 150 (60-480) s during follow-up. After prolongation of the SRD, no more inadequate therapies due to AA were delivered. In pts with new implanted ICD and known TAA, which is hemodynamically tolerated, the SRD should be programmed beside all other available detection parameters for improving the increase of specificity at least 135 s to avoid inadequate therapies of the ICD. In pts with unknown TAA, SRD should be prolonged to 135 s at least the second tachyarrhythmic episode, which is hemodynamically well tolerated.

A recently developed cutting balloon was used for coronary angioplasty in 21 patients (4 women, 17 men; mean age 57.6 [36-81] years) with coronary heart disease (angioplasty of the right coronary artery in 4, of the circumflex branch in 4, and of the anterior interventricular branch in 13 patients). The balloon contains 3-4 longitudinally arranged metal cutters to prevent uncontrolled vessel tears. An average stenosis reduction from 84 +/- 8.6% to 30 +/- 10.6% was achieved in ten patients. In the eleven others a second dilatation with a conventional balloon was necessary because of a residual stenosis of over 50% after the first dilatation with the cutting balloon. This reduced the original stenosis from 78.6 +/- 9.4% to 30.4 +/- 9.9%. Complete occlusion at the place of previous dilatation occurred in one patient 14 hours after the procedure, due to a dissection which required a stent implantation. These preliminary results suggest that the cutting balloon can achieve a stenosis reduction similar to that with a conventional balloon.

In order to investigate the influence of hydration on the backbone of a peptide or protected amino acid, the successive aggregation of water to Ac-Phe-OMe is analysed by means of IR/UV double resonance spectroscopy. To achieve meaningful results the spectra have been recorded in the region of the amide A and OH stretching vibrations as well as the amide I/II modes. Comparison with ab initio and DFT calculations leads to size-selective structural assignments. Two isomers of the mono- and dihydrated clusters and one isomer of the trihydrated cluster are observed in the molecular beam leading to a formation of the first solvation shell of the backbone. In case of the trihydrated cluster the backbone geometry is remarkably changed compared to the structure of the monomer since a network of water molecules can be formed.

Despite continuous improvement in balloon-catheter and guidewire technology, acute coronary occlusion after PTCA occurs in 2–5% [1, 2]. With increasing numbers of multiple stenoses that are dilated, this complication has become an even greater problem. In most cases, the underlying mechanism is a dissection, resulting in luminal obstruction by an intimal flap [3–5].

Minipigs (20–30 kg bodyweight) were fed an atherogenic diet (2% cholesterol), starting 4 wks prior to endothelial balloon-denudation in one coronary artery. Another 4 weeks later, a balloon-mounted tantalum-stent (2.0–4.0 mm diameter) was implanted at the site of previous endothelial damage. Animals were given 10,000 U heparin immediately before PTCA and stent-implantation. 100 mg acetyl-salicylic acid per day were given orally afterwards. Stent-implantation could be performed at the selected site in all cases without complications due to good radiopacity of the tantalumstent. 4 weeks later, repeat angiography for assessment of stented vessel patency and eventual stenoses was performed. Subsequently, hearts were perfusion-fixed with glutaraldehyde for histologic examination. All vessels were patent (left circumflex, n = 4) left anterior descending coronary artery, n = 1) on angiography. Stents were covered by endothelium. Results 3 months after stent-implantation are currently assessed.

A high restenosis rate of conventional coronary angioplasty (PTCA) and an even higher reocclusion rate of recanalized vessels encourages the development of new interventional techniques. Percutaneous Excimer laser angioplasty (PTLA) provides an alternative technique to ablate the obliterating atherosclerotic plaque without thermal damage to the surrounding tissue.

Ten patients, two women and eight men, were treated with the new balloon-expandable Wiktor Stent for acute coronary occlusion after PTCA. Two patients presented with an acute myocardial infarction. Stents with a diameter of 3.0 or 3.5 mm were implanted into the right coronary artery (n = 7), the left anterior descending (n = 2) artery, and the left circumflex coronary artery (n = 1). Stent implantation in the target segment was successful in all cases. Afterwards, patients received coumadine for 3 months and 100 mg acetylsalicyclic acid per day. We observed one acute occlusion after 8 h. Late occlusion occurred in two patients after cessation of anticoagulation within 3 weeks. Control angiography after 6 months in seven patients revealed stenosis within the stent in two cases.

The beta-blocker carvedilol has been shown to induce vasodilation in patients with coronary artery disease. In a double-blind, randomized, placebo-controlled cross-over study, we looked for the acute vasodilating effect after i.v. administration in patients with heart failure. In 10 patients with coronary artery disease and six patients with dilated cardiomyopathy, all with an ejection fraction lower than 40%, the rate-pressure-product during supine ergometry and Swan-Ganz-catheterization rose to a significantly smaller extent after 5 mg carvedilol i.v. compared to placebo. This was mainly due to a lower heart rate at rest and during exercise, while blood pressure was not changed compared to placebo. Calculated total peripheral resistance during exercise after carvedilol was higher--significantly so in the CAD-group--than after placebo. These results show that in patients with heart failure, an acute vasodilating effect of i.v. carvedilol is not detectable.

We investigated the acute effect of the new long-acting ACE-inhibitor ramipril on angina-limited exercise tolerance and exercise-induced ST-depression in 18 normotensive patients with angiographically confirmed coronary artery disease in a double-blind, placebo-controlled study. Patients underwent a repeat exercise ECG 24 hours following either 5 mg ramipril p.o. or placebo. Plasma-ACE activity (nmol/min x ml) in the ramipril-group (n = 8) was significantly reduced 24 hours after 5 mg ramipril compared to placebo (n = 10): 14.0 +/- 2.0 vs 87.2 +/- 13.5, p less than 0.001. Exercise-induced ST-segment depression was not different before and after ramipril or placebo. Heart rate at rest and during angina-limited exercise was not different between the first exercise-ECG and that after ramipril or placebo, nor between the groups. Systolic arterial pressure (mmHg) was slightly, but insignificantly, lower after than before ramipril at rest (113.8 +/- 5 vs 125 +/- 6.8) and at maximal exercise, 1.5 watt/kg (150 +/- 9.4 vs 158.3 +/- 13.3). In the placebo group, blood pressure at rest and during exercise was not different before and after placebo: 126 +/- 4.7 vs 125.5 +/- 7.5 and 157.5 +/- 3.8 vs 158 +/- 3.6. Rate-pressure-product (mmHg/min x 1000) at rest prior to (8.42 +/- 0.83 and 8.95 +/- 0.51) and after ramipril or placebo (8.00 +/- 0.94 and 8.93 +/- 0.71) showed no significant difference. Similarly, rate-pressure-product at maximal exercise was equal among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)