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A 32-year-old, otherwise healthy woman was admitted after successful out-of-hospital resuscitation due to ventricular fibrillation. Established cardiac, pulmonary, metabolic, and toxicological causes were excluded. However, persisting (biphasic) negative T waves in the inferior ECG leads and premature ventricular contractions (PVC) were noted. PVC morphology indicated a focus alternating between the posterior papillary muscle/the left posterior fascicle and the left ventricular outflow tract region/anterior papillary muscle. Echocardiography revealed a bileaflet mitral prolapse with mild mitral valve regurgitation. This case is a typical presentation of the recently described malignant bileaflet mitral valve prolapse syndrome. The patient was discharged without overt neurological deficit after implantation of a cardioverter-defibrillator.

Stress echocardiography (SE) is a powerful functional imaging technique to assess cardiac performance under work conditions. The main indication is the detection of myocardial ischemia due to coronary artery disease (CAD), however it can also be used in patients with structural heart disease (e. g. valvular disease, hypertrophic obstructive cardiomyopathy). Dynamic or pharmacological (dobutamine / adenosine) modalities are available to induce cardiac stress, basically depending on the clinical problem and the patient's ability to exercise. Exercise on a treadmill or a semi-supine bicycle is the most physiological way to induce stress. Dobutamine stimulation is useful in patients who are unable to exercise and for detection of viable myocardium in hypo- or akinetic segments. Adenosin-induced hyperaemia causes steal effects in myocardial segments with significant CAD. Main limitations of SE are the need for an appropriate acoustic window and the user-dependent variability with regard to the interpretation of the results., (© Georg Thieme Verlag KG Stuttgart · New York.)

Velocity and deformation imaging by Doppler and newer techniques based on "speckle tracking" in 2-D datasets have substantially added to the ability of echocardiography to detect myocardial ischemia. Typical parameters include tissue velocities and regional deformation ("strain") and deformation rate ("strain rate"), which with the Doppler-independent new techniques ("2-D strain", "velocity vector imaging") can be measured in several directions, largely independent of insonation angle. All of these techniques can be readily combined with stress echocardiography; so far, published results are mostly based on the combination with dobutamine echocardiography. Typical signs of myocardial ischemia include a decrease in tissue velocities, deformation rates, and deformation. Additionally, systolic deformation occurs later in systole and often still goes on after aortic valve closure (postsystolic deformation). While tissue velocities are unable to clearly identify regional ischemia because of tethering of the neighboring wall segments and a physiological variation in regional tissue velocities, deformation parameters are better suited to detect regional ischemia. The limited literature on the detection of myocardial ischemia by these techniques clearly shows a value of velocity and deformation imaging especially in those cases where qualitative visual assessment of wall motion remains ambiguous. Due to rapid evolution of these techniques, a final assessment of their potential is not possible yet.

Tissue Doppler imaging is a new ultrasound technique for the acquisition and analysis of myocardial velocity and deforming parameters in the human heart. In cardiology this innovative technique is used to identify ischemic regions and stunned areas after cardiac infarction and to diagnose dyssynchrony. In the last two years, our research group has been using this technique extensively on fetal hearts. It is possible to establish the fetal cardiac cycle clearly just by analyzing the typical courses of myocardial velocity curves. The quality of the curves is comparable to the results in adult cardiology. Consequently, many innovative analysis options can be acquired, e.g., the comparison of the kinetics of several myocardial regions in the cardiac cycle, the determination of pre- and post-systolic intervals (isovolumic contraction time, isovolumic relaxation time), the evaluation of diastolic function by analyzing the E(m) and A(m) waves and the detection of the atrial contraction. These parameters are currently used in cardiology for extended function analysis. Tissue Doppler imaging is the first step in parametric imaging of the fetal heart and consequently marks the beginning of a new era in fetal echocardiography.

Tissue Doppler and its derived parameters strain and strain rate show characteristic changes in patients with cardiomyopathy. Longitudinal systolic (S) and early diastolic (E') peak tissue velocities are reduced in the basal segments of the left ventricle in patients with dilated, hypertrophic, and restrictive cardiomyopathies, and in the right ventricular free wall in patients with arrhythmogenic dysplasia of the right ventricle. Similarly, strain and strain rate are lower than in normals. These changes are detectable in asymptomatic, genetically affected patients and in early stages of cardiomyopathy, where conventional echo signs such as impaired left ventricular ejection fraction or increased wall thickness are not yet present. Thus, tissue Doppler analysis may contribute to better identifying carriers of disease and subclinical early stages of cardiomyopathy. However, lack of measurement standardization and small numbers of cardiomyopathy patients examined by Doppler, together with difficulty in defining reliable normalcy ranges, still hamper widespread clinical use of this new tool.

During recent years, heart failure has been recognized as a complex disease involving both hemodynamic abnormalities caused by reduced contractile forces and neurohormonal changes characterized by an increase in sympathetic tone and an activation of the renin-angiotensin-aldosterone system as well as the endothelial pathways. Neurohumoral factors represent the natural response of the individual to heart failure. Among them natriuretic peptides, i. e., brain natriuretic peptide (BNP) and amino-terminal pro BNP (Nt-proBNP) release have recently been shown to be a reliable and rapid marker for diagnosis, optimization of pharmacological treatment and risk stratification in heart failure patients. This article summarizes important aspects of the release of natriuretic peptides as a guide for diagnosis, therapy and prognosis of patients with heart failure and cardiac resynchronization therapy.

Transthoracic echocardiography provides numerous options for the evaluation and quantification of contractile cardiac asynchrony in patients with advanced heart failure. Important information on the presence of asynchrony can be obtained already during a standard routine examination with conventional techniques (2D, M-mode and Doppler). Newer techniques such as tissue Doppler imaging and real-time 3D-echocardiography enable us to better quantify the degree of asynchrony. The following article describes the echocardiographic features of asynchrony and algorithms for the improved identification of suitable patients for cardiac resynchronization therapy.

Background and Aim: Cardiac resynchronization therapy (CRT) with biventricular stimulation is a new therapeutic option for patients with advanced heart failure and left ventricular asynchrony. The presence of a left bundle branch block morphology in the electrocardiogram is presently the most important selection criterion. Transthoracic echocardiography provides important additional information on the ventricular contraction sequence and the hemodynamic consequences of asynchrony. This may help to identify suitable patients, to improve the selection criteria and to optimize CRT during follow-up. This article discusses the potential techniques and limitations and provides practical guidance for the individual patient follow-up.

Background and Aim: Cardiac resynchronization therapy (CRT) by pacemakers is a new therapeutic principle in the treatment of advanced heart failure. It aims to correct the intracardiac conduction disturbances that are frequently associated with left ventricular dysfunction and thus reduce their negative hemodynamic consequences. In early studies on CRT, acute improvement in cardiac hemodynamics could be shown. Nowadays it is accepted that cardiopulmonary exercise capacity is also improved in the long term with CRT. In addition, reduction of functional mitral regurgitation and reverse left ventricular remodeling have been demonstrated in the majoriy of patients. The results of recent studies demonstrate a reduction in mortality and hospitalizations by CRT. The results of these trials have led to an accepted indication for CRT as an adjunct treatment in heart failure in the updated US guidelines. However, about 30% of patients undergoing device implantation according to currently accepted implant criteria will show no substantial improvement with CRT. Therefore, other indicators to identify therapy responders must be developed in the future, e.g. by using echocardiographic techniques. Moreover, it is yet unclear in how many patients a defibrillator backup is necessary for a CRT patient. This article summarizes the current status of CRT with regard to indications and clinical results. In addition, unresolved issues are discussed and potential developments for the future highlighted.

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.

The case of a quadricuspid aortic valve diagnosed in adult age is reported. A 67-year-old patient, who had no previous diseases or cardiovascular complaints, presented in the clinic for an embolic occlusion of the left retinal artery. Isolated moderate aortic regurgitation was diagnosed clinically and echocardiographically. For its further evaluation and for seeking embolic sources, multiplane transesophageal echocardiography was performed, which discovered a quadricuspid aortic valve as the cause of aortic regurgitation and major atherosclerotic lesions in the ascending aorta and the aortic arch as possible cause of the embolic event. The fourth, accessory cusp, smaller than the other three, was localized between the non-coronary and left coronary cusp. In the short axis view the quadricuspid aortic valve showed in diastole a "X"-configuration, with a persistent central orifice between the commissures, which was the cause of the regurgitation jet in color Doppler examination, and in the systole a trapezoid opening pattern. In the long-axis view the valve showed a tricuspid closing pattern. The quadricuspid aortic valve can be exactly diagnosed by multiplane transesophageal echocardiography.