[Low flow/low gradient aortic valve stenosis : clinical and diagnostic management]. / "Low-Flow/Low-Gradient"-Aortenklappenstenose : Klinisches und diagnostisches Spektrum.

Low gradient aortic stenoses (AS) represent a special challenge for physicians with respect to an exact diagnosis and optimal therapy. The difficulty lies in the estimation of the severity of AS which is decisive for subsequent treatment and the prognosis. Low flow and low gradient can be due to systolic or diastolic dysfunction by high-grade as well as by medium-grade AS and be of non-valvular origin. The latter group is to be interpreted as pseudoaortic stenosis as long as the low flow can successfully be raised by interventional means. However, only patients in the first group can be expected to profit from valve replacement and for patients in the second group the accompanying diseases must be the focus of therapeutic treatment. Therefore, according to recent European surveys up to 30% of patients with severe AS are undertreated due to false estimation of the severity of stenosis and perioperative risk stratification. Furthermore, follow-up investigations have shown that patients with low flow/low gradient stenosis and borderline-normal ejection fraction (EF) are in an advanced stage of the disease because they have often developed a severe reduction in longitudinal myocardial function and in addition have pronounced myocardial replacement fibrosis due to cardiac remodelling despite a preserved EF. Therefore, aortic valve area, mean pressure gradient and EF alone cannot be taken into consideration for the management of patients with severe AS but a comprehensive assessment of the hemodynamics, such as stroke volume, special functional parameters as well as individual clinical appearance is essential for precise diagnostic and therapeutic decision making.

[Improved quality of coronary diagnostics and interventions by virtual reality simulation]. / Qualitätsverbesserung von Koronardiagnostik und -intervention durch "Virtual-Reality"-Simulation.

Currently, more than 800,000 diagnostic procedures and 300,000 percutaneous coronary interventions are performed annually in 556 catheter laboratories in Germany. These numbers document the importance of training programs in interventional cardiology. However, this need is in sharp contrast to the time constraints for continuing medical education in Germany due to personnel and financial restrictions. A possible solution for this dilemma could be new training programs which partially supplement conventional clinical training by simulation-based medical education. Currently five virtual reality simulators for diagnostic procedures and percutaneous coronary interventions are available. These simulators provide a realistic hands-on training comparable to flight simulation in aviation.The simulator of choice for a defined training program depending on the underlying learning objectives could either be a simple mechanical model (for puncture training) or even a combination of virtual reality simulator and a full-scale mannequin (for team training and crisis resource management). For the selection of the adequate training program the basic skills of the trainee, the learning objectives and the underlying curriculum have to be taken into account. Absolutely mandatory for the success of simulation-based training is a dedicated teacher providing feedback and guidance. This teacher should be an experienced interventional cardiologist who knows both the simulator and the selected training cases which serve as a vehicle for transferring knowledge and skills.In this paper the potential of virtual reality simulation in cardiology will be discussed and the conditions which must be fulfilled to achieve quality improvement by simulation-based training will be defined.

[Functional cardiac MRI for assessment of aortic valve disease]. / Aortenklappenstenose im MRT mit Dynamik und 3D.

Aortic valve disease shows a rising incidence with the increasing mean age of Western populations. The detection of hemodynamic parameters, which transcends the mere assessment of valve morphology, has an important future potential concerning classification of the severity of disease. MRI allows a non-invasive and a spatially flexible view of the aortic valve and the adjacent anatomic region, left ventricular outflow tract (LVOT) and ascending aorta. Moreover, the technique allows the determination of functional hemodynamic parameters, such as flow velocities and effective orifice areas. The new approach of a serial systolic planimetry velocity-encoded MRI sequence (VENC-MRI) facilitates the sizing of blood-filled cardiac structures with the registration of changes in magnitude during systole. Additionally, the subvalvular VENC-MRI measurements improve the clinically important exact determination of the LVOT area with respect to its specific eccentric configuration and its systolic deformity.

Implementing artificial insemination as an effective tool for ex situ conservation of endangered avian species.

Approximately 503 of the known species of birds are classified as 'endangered' or 'critical'. Captive propagation programs have proven useful in maintaining genetic diversity and restoring wild populations of certain species, including the Peregrine falcon, California condor and Whooping crane. Artificial insemination (AI) has the potential of solving problems inherent to reproductive management of small, closed populations of endangered birds, including dealing with demographic instability, physical and behavioral disabilities, sexual incompatibility, lack of synchrony, and need to maintain gene diversity. In this review, we address the necessary methods and factors that allow AI to be applied effectively to manage rare bird populations. It is clear that semen availability and quality are the greatest limiting factors to implementing consistently successful AI for birds. Behavioral sensitivity to animal handling and the ability to minimize stress in individual birds also are keys to success. Multiple, deep vaginal inseminations can improve fertility, particularly when semen quality is marginal. Laparoscopic methods of semen transfer also have produced fertile eggs. All of these practices leading to successful AI remain dependent on having adequate basic knowledge on female reproductive status, copulatory behavior, endocrine profiles and duration of fertility, especially as related to oviposition. The overall greatest challenge and highest priority is defining these normative traits, which are highly species-specific.

Contemplative meditation reduces ambulatory blood pressure and stress-induced hypertension: a randomized pilot trial.

A total of 52 pharmacologically untreated subjects with essential hypertension were randomly allocated to either 8 weeks of contemplative meditation combined with breathing techniques (CMBT) or no intervention in this observer-blind controlled pilot trial. CMBT induced clinically relevant and consistent decreases in heart rate, systolic and diastolic blood pressure if measured during office readings, 24-h ambulatory monitoring and mental stress test. Longer-term studies should evaluate CMBT as an antihypertensive strategy.

Natriuretic peptides and myocardial oxygen supply-to-demand ratio in patients with aortic stenosis.

BACKGROUND: In severe aortic stenosis (AS), brain natriuretic peptide (BNP) and its precursor, the amino-terminal pro-hormone (NT-proBNP) are independent predictors of outcome. Deterioration of cardiac function in AS is currently assessed by symptomatology and echocardiography to determine the optimal time point for surgery. We investigated whether BNP or NT-proBNP may help to estimate the individual risk of patients for subendocardial ischaemia in patients with moderate and severe AS. DESIGN: In 71 patients with AS and 24 controls, the association of plasma natriuretic peptides with invasively measured haemodynamic parameters, including the myocardial oxygen supply-to-demand ratio [diastolic pressure time index/systolic pressure time index (DPTI/SPTI)] was cross-sectionally assessed. RESULTS: Levels of natriuretic peptides increased with severity of AS. In patients with moderate AS (n = 30), natriuretic peptides differentiated between symptomatic and asymptomatic status (P = 0.01). BNP and NT-proBNP values correlated negatively with DPTI/SPTI (r = -0.58 and -0.51, P < 0.001, respectively) and left ventricular (LV) ejection fraction (EF) (r = -0.52 and -0.59, P < 0.001, respectively). DPTI/SPTI correlated with aortic valve area (P < 0.0001) but not with EF. Receiver operating characteristic analysis determined cut-off values of > 450 pg mL(-1) for BNP and of > 1800 pg mL(-1) for NT-proBNP for those AS patients who were at highest risk for subendocardial ischaemia (i.e. DPTI/SPTI < 0.22) in combination with impaired LV systolic function (i.e. EF < 45%). CONCLUSIONS: Elevated natriuretic peptides show cardiac deterioration in AS and may help to identify those patients in need for early valve replacement.

[Quality assurance in echocardiography. Three-level system in formation and qualifying and concept of an external quality review]. / Qualitätsleitlinien Echokardiographie Stufenkonzept Ausbildung, Qualifizierung und Externe Qualitätssicherung.

Measures of quality assurance in echocardiography can be categorized according to standard principles into measures of reviewing structure, processing, and results. This document contains 1) the description of a three level system for education and qualifying in echocardiographic examinations (quality of structure) and 2) the draft of an external quality assurance process for reviewing the results of one echocardiographic investigator or of one laboratory of echocardiography (quality of results). The document also contains a draft description of a nationwide independent institution for certification, which is needed for both projects.A level 1 investigator should be able to perform and interpret a basic investigation. A basic investigation allows to exclude most of all cardiac diseases that can be diagnosed by echocardiography, and pathological findings should be filtered out. A level 2 investigator is able to perform an extended examination, and a comprehensive echocardiographic diagnosis can be established after her or his examination. Additional specific training and experience is necessary to be certified for TEE and stress echo examinations. A level 3 echocardiographer has done research work in echocardiography and should have performed certified teaching courses in echocardiography. The external quality assurance process should provide the possibility to certify the results and reports of a single investigator or of an echo laboratory, according to standard principles of reviewing the records. The process of certification is exclusively performed on a voluntary basis. The nationwide institution of certification should be part of the academy of education in cardiology of the German Society of Cardiology.

[A structured report data set for documentation of echocardiographic studies--Update 2004]. / Strukturierter Datensatz zur Befunddokumentation in der Echokardiographie--Version 2004 für den Arbeitskreis "Standardisierung und LV-Funktion" der Arbeitsgruppe Kardiovaskulärer Ultraschall der DGK.

A standardized documentation of echocardiographic studies is necessary to provide comparability of data and to realize software-based documentation and electronic communication, both essential for quality management in echocardiography.Therefore, the subgroup on "Standardization and LV function" of the working group on cardiovascular ultrasound of the German Cardiac Society developed a consensus report for documentation of echocardiographic studies, which was first published in 2000. This report represents the current update of the standardized documentation for echocardiography; its impact for quality management in conjunction with the "guidelines echocardiography" is discussed.

[Documentation in the cardiac catheterization laboratory using electronic databases--experiences in 176 German cath labs]. / EDV-gestützte Dokumentation im Herzkatheterlabor: Eine Bestandsaufnahme.

Due to the introduction of a variety of new features to the German health system, such as a new reimbursement system for inpatient work based on diagnosis-related groups, an obligation to detailed documentation for total quality management, as well as due to the continuing increase in the amount of imaging and other data within invasive cardiology, the use of electronic databases for documentation in the cardiac cath lab is of significant importance. The user friendliness and robustness of the software system for daily clinical practice is crucial for the acceptance of electronic documentation systems by physicians, nurses and technicians. This survey was aimed to explore the current practice and experiences of German cardiac catheterization labs with electronic databases particularly designed for documentation in invasive cardiology, including report generation of cath studies, risk and complication management and logistics for medical material ordering for the cath lab. Of the 176 hospitals and practices having agreed in taking part in this surveillance 165, are currently using an electronic database for administration of medical data and study reports. In 64% of the cath labs, a sub-specialized software system for detailed documentation of the course and the results of an invasive procedure, the human and material resources used, generation of the cath report, and documentation of procedural and post-procedural complications for total quality management is used. The acceptance and satisfaction with the software solutions currently available reveals to be rather inhomogeneous. While user-friendliness and flexibility of a number of software products were positively mentioned, main issues, such as missing hardware of software interfaces with the hospital information system for patient administration, missing stability of several systems, image management too complex and report configuration too inconvenient for daily clinical practice, were criticized. In general, in the light of continuing increase of the amount of clinical and imaging data as well as due to the legal obligation of detailed procedural documentation in all areas of invasive cardiology, a documentation system based on electronic databases bears the potential of an enormous economization of the daily workload of a cardiac cath lab. Prerequisites for the acceptance of such a system in clinical practice is not only the stability and reliability of the system but also the ability to link such a sub-system to existing databases via suitable interfaces and the flexibility of the system for modification of its features to meet the individual requirements of each user.

[Cathi-training on virtual patients for catheter interventions]. / Cathi-training on virtual patients for catheter interventions.

In this paper we present a trainings system for catheter interventions, especially PCTAs also called ballon dilatation. Despite the large number of such interventions the education of the cardiologist is still based on learning on the patient. This means risk to the patient and additional cost. To overcome these problems we developed the CathI system (Catheter Instruction System), a realistic computerbased training system. It provides the physician with the same equipment found in a catheter laboratory, e.g. original control instruments for the flouroscopy system, syringes, catheters, and guide wires. CathI only replaces patient and C-arm by a virtual patient and a virtual x-ray system.

[Percutaneous revascularization of multivessel coronary disease using stents - a multicenter, prospective study]. / Perkutane Revaskularisation der koronaren Mehrgefässerkrankung nach Einführung von Stents - Eine multizentrische, prospektive Studie.

BACKGROUND AND OBJECTIVE: Symptomatic patients with multivessel coronary disease (MVD) benefit from both coronary artery bypass grafting (CABG) and percutaneous coronary angioplasty (PTCA). The >>German Angioplasty Bypass Investigation<< (GABI-I) trial randomized patients to one of these treatment strategies between 1986 and 1991. In order to evaluate the impact of current technology, in particular coronary stents, the GABI-II trial was initiated, which in 1996 and 1997 prospectively enrolled patients according to the initial GABI-I criteria. PATIENTS AND METHODS: Into the study 136 consecutive patients (108 men, 28 women; 63 +/- 12 years) were included. Patients from GABI-I served as controls. RESULTS: A mean of 2.1 +/- 0.5 vessels were treated per patient (vs. 1.9 +/- 0.5 vessels in the PTCA arm of GABI-I) and 63 % of the lesions were covered with stents. With respect to the primary endpoint less patients remained with a CCS class III or IV in GABI-II after 12 months (1,5 % vs. 8 % in the PTCA arm of GABI-I, p<0,01). No patient required emergency or urgent bypass operation in GABI-II (vs. 9 % in GABI-I, p < 0.01). After 12 months, 8 % of the patients were sent for bypass surgery (CABG) vs. 21 % in GABI-I (p < 0.001), and 20 % (vs. 23 % in GABI-I) of the patients underwent Re-PTCA. The percentage of patients without reinterventions was 72 % vs. 56 % in GABI-I (p < 0.01), but remained lower compared to patients randomized to CABG in GABI-I (94 %, p < 0.001). CONCLUSION: PTCA in patients with MVD is still associated with a higher reintervention rate as compared with CABG. However, in contrast to angioplasty a decade ago, PTCA in conjunction with stents significantly lowered the need for subsequent revascularization, which was mainly driven by the reduced necessity for bypass surgery.

A novel perfusion catheter for hybrid procedures in minimally invasive bypass surgery.

BACKGROUND: Combined off-pump bypass grafting and percutaneous coronary intervention (hybrid procedures) is supposed to be beneficial for high-risk patients. We developed a novel perfusion catheter to facilitate these hybrid interventions. METHODS: First, we tested coagulatory activation in vitro. Afterwards, 6 landrace pigs underwent active coronary perfusion of the LAD. In a second study, 15 pigs underwent off-pump bypass surgery (LIMA to LAD grafting) and the catheter was used to provide myocardial perfusion and prevent bleeding at the site of the coronary anastomosis. RESULTS: In the in vitro perfusion studies, no activation of coagulation or clotting occurred. Active coronary perfusion was feasible without signs of regional myocardial ischemia or coagulation over a 50-minute period. During off-pump bypass surgery, the catheter prevented bleeding in the operation field and facilitated the surgical procedure. CONCLUSION: The new perfusion catheter can optimize the conditions of off-pump bypass surgery by preventing bleeding in the operation field, maintaining myocardial perfusion and allowing direct angiographic control of the anastomosis. Therefore, this new technique could be an important tool to facilitate hybrid interventions.

Postpericardiotomy syndrome and cardiac tamponade as a late complication after pacemaker implantation.

In a 78-year old woman, pacemaker implantation was complicated by a transient perforation of the endocardial lead. The patient was in stable condition for up to 7 weeks after implantation, after which pericardial effusion and subacute cardiac tamponade developed and pericardiocentesis became necessary. This case illustrates that even after initially uneventful pacemaker lead perforation, careful, long-term follow-up is necessary to recognize the potential development of late postpericardiotomy syndrome.

Assessment of myocardial infarction in humans with (23)Na MR imaging: comparison with cine MR imaging and delayed contrast enhancement.

PURPOSE: To demonstrate the feasibility of sodium 23 ((23)Na) magnetic resonance (MR) imaging for assessment of subacute and chronic myocardial infarction and compare with cine, late enhancement, and T2-weighted imaging. MATERIALS AND METHODS: Thirty patients underwent MR imaging 8 days +/- 4 (subacute, n = 15) or more than 6 months (chronic, n = 15) after myocardial infarction by using a (23)Na surface coil with a double angulated electrocardiogram-triggered three-dimensional gradient-echo sequence at 1.5 T. In addition, cine, inversion-recovery gradient-echo, and, in the subacute group, T2-weighted images (n = 9) were obtained. Myocardial infarction mass was depicted as elevated signal intensity or wall motion abnormalities and expressed as a percentage of total left ventricular mass for all modalities. Correlations were tested with correlation coefficients. RESULTS: All patients after subacute infarction and 12 of 15 patients with chronic infarction had an area of elevated (23)Na signal intensity that significantly correlated with wall motion abnormalities (subacute; r = 0.96, P <.001, and chronic; r = 0.9, P <.001); three patients had no wall motion abnormalities or elevated (23)Na signal intensity. Only 10 patients in the subacute and nine in the chronic group revealed late enhancement; significant correlation with (23)Na MR imaging occurred only in subacute group (r = 0.68, P <.05). Myocardial edema in subacute infarction correlated (r = 0.71, P <.05) with areas of elevated (23)Na signal intensity but was extensively larger. CONCLUSION: (23)Na MR imaging demonstrates dysfunctional myocardium caused by subacute and chronic myocardial infarction.

Use of intravascular ultrasound to compare effects of different strategies of lipid-lowering therapy on plaque volume and composition in patients with coronary artery disease.

BACKGROUND: We studied whether lipid-lowering therapy with atorvastatin (target LDL cholesterol [LDL-C] <100 mg/dL) compared with a moderate treatment regimen that used other lipid-lowering drugs led to a lesser progression of atherosclerosis and to different changes in plaque echogenicity in patients with coronary artery disease. METHODS AND RESULTS: This study was a 12-month, open-label, randomized, multicenter trial, which used serial 3D intracoronary ultrasound to calculate plaque volume and plaque echogenicity. After transcatheter therapy, 131 patients were randomized (atorvastatin n=65, usual care n=66). The target plaque had to be a minor lesion (ie, a diameter stenosis of <50% on angiography). After 12 months, mean LDL-C was reduced from 155 to 86 mg/dL in the atorvastatin group and from 166 to 140 mg/dL in the usual care group. Mean absolute plaque volume showed a larger increase in the usual care group compared with the atorvastatin group (usual care 9.6+/-28.1 mm(3), atorvastatin 1.2+/-30.4 mm(3); P=0.191). The hyperechogenicity index of the plaque increased to a larger extent for the atorvastatin group than for the usual care group, with a significant treatment effect for the percent change (atorvastatin 42.2%, usual care 10.1%; P=0.021). CONCLUSIONS: One year of lipid-lowering therapy to <100 mg/dL LDL-C most likely led to a slowdown of plaque growth of minor lesions. The significantly larger increase in plaque hyperechogenicity is most likely due to a change in plaque composition.

Persistence of the eustachian valve in secundum atrial septal defects: possible implications for cerebral embolism and transcatheter closure procedures.

Transcatheter closure of large secundum atrial septal defects is now accepted clinical practice. With the introduction of easily applicable closure devices the indications for this procedure have been expanded to include the closure of patent foramen ovale after cerebral stroke of unknown origin. In some of these patients a persistent eustachian valve is present. The clinical relevance of this finding is still unclear. A 36 year old patient with a brainstem stroke of unknown origin and a secundum atrial septal defect in combination with a persisting prominent eustachian valve is reported. The potential role of the eustachian valve in the genesis of the stroke and the difficulties during transcatheter closure of the defect because of the persisting valve are discussed.

Haemodynamic quantification of different provocation manoeuvres by simultaneous measurement of right and left atrial pressure: implications for the echocardiographic detection of persistent foramen ovale.

AIMS: Persistent foramen ovale (PFO) is found in 9.2--32% of echocardiographic examinations. The gold standard for the detection of a PFO is transoesophageal echocardiography (TEE) and the mostly used provocation test is the Valsalva manoeuvre. The aim of our study was to evaluate the effectiveness of the Valsalva manoeuvre compared to other provocation tests by simultaneous haemodynamic measurements of the right and left atrial pressure. METHODS: Fifty patients underwent Swan-Ganz catheterization. Right atrial pressure and pulmonary capillary wedge pressure, which corresponds to the left atrial pressure, were measured simultaneously. The following manoeuvres were compared: the Valsalva manoeuvre, coughing, deep inspiration and expiration pressures of 20 mmHg, 40 mmHg and 60 mmHg. The main objective of our study was to compare the occurrence of pressure gradients (right atrial pressure> left atrial pressure). For further quantification mean gradients, time duration of pressure overlap, as well as products of mean gradients and overlap time were analysed. RESULTS: During the Valsalva manoeuvre a significant pressure gradient could be observed in 84% of the patients, followed by an expiration pressure of 60 mmHg (82%), inspiration (78%), expiration pressure of 40 mmHg (76%), coughing (75%) and an expiration pressure of 20 mmHg (62%). Comparing the mean gradients and the products of mean gradients and overlap time duration during the different manoeuvres, we could detect the significantly best results with the Valsalva manoeuvre. CONCLUSIONS: The Valsalva manoeuvre might be the most effective test to provoke a right-to-left atrial shunt for the detection of a PFO during echocardiographic examinations.

[A standardized documentation structure for data documentation in echocardiography. Work Team on Standards and LV Function of the Work Group on Cardiovascular Ultrasound of the German Society of Cardiology, Heart and Circulation Research]. / Eine standardisierte Dokumentations-struktur zur Befunddokumentation in der Echokardiographie. Für den Arbeitskreis Standardisierung und LV-Funktion der Arbeitsgruppe Kardiovaskulärer Ultraschall der Deutschen Gesellschaft für Kardiologie--Herz- und Kreislaufforschung.

Presently, there are no well-defined standards for documentation of echocardiographic studies. Nevertheless, standards are essential to provide comparability of data and to realize electronic communication, both essential for quality management in echocardiography. Therefore, the working group "Standards and LV function" of the German Society of Cardiology developed a consensus for documentation of echocardiographic studies. In the present paper this consensus is presented and illustrated by typical clinical examples. Additionally, a prototype of a user-oriented software based on this data set is presented. The complete data set for transesophageal and transthoracic echocardiography and the software prototype can be downloaded at http:@echo.ma.uni-heidelberg.de.

[Noise field findings in 24 patients with coronary heart disease]. / Rauschfeldbefunde bei 24 Patienten mit koronarer Herzkrankheit.

PURPOSE: In earlier studies it was shown that patients with vascular disturbances (e.g. sudden hearing loss) had white-noise field campimetry abnormalities despite normal visual fields. The aim of this study was to clarify whether patients with coronary heart disease (CHD) have such disturbances in the white-noise field campimetry, too. PATIENTS AND METHODS: Twenty-four patients (m:f = 23:1; mean age 58 +/- 9 years) with an angiographically documented CHD and 30 healthy controls (m:f = 29:1; mean age 54 +/- 7 years) were examined. In order to evaluate the morphological and functional ocular status, we examined the following parameters: morphological status, visual acuity, intraocular pressure, perimetry (Tübinger Automatic Perimeter 2000 ct, Oculus) and white-noise field campimetry (Tübinger Electronic Campimeter, Oculus). RESULTS: Fifteen patients had had a cardiac infarction. Twenty-one patients, but only 6 controls had alterations in perilimbal vessels of the conjunctiva and sixteen patients had a tortuousity of retinal vessels. The visual acuity, the intraocular pressure, the cup/disc ratio and the visual fields were within normal ranges. However, twenty patients and 5 controls were abnormal in the white-noise field campimetry. DISCUSSION: Although patients with CHD appeared unaffected in the standard eye examinations, the disturbances in the white-noise field campimetry indicated a functional visual impairment. Together with the changes in the perilimbal vessels of the conjunctiva and the retinal vessels, a disturbed ocular microcirculation as the underlaying cause could be discussed.