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Many patients with severe aortic stenosis have a "low-flow, low-gradient" aortic stenosis. The management of these patients can be quite difficult, as these patients often show impairment of the left ventricle, which can lead to false measurements of the severity of stenosis and also leads to a higher risk during aortic valve replacement. More diagnostic tools than only standard echocardiography are needed to correctly differentiate true severe aortic stenosis from pseudo severe aortic stenosis.

Remote follow-up of patients with implantable electronic cardiac devices (IECD) is a scientifically well-evaluated and technically mature method. Advantages over conventional follow-up include rapid detection of clinically relevant events (i. e. arrhythmias) and of technical problems. Additionally, telemetric follow-up of IECDs has a high degree of acceptance among both patients as well as health care professionals and carries the potential to reduce health care costs. The implementation of a remote follow-up programme is associated with organisational, infrastructural and legal aspects, which are reviewed.

Due to the technical advances in pumps, oxygenators and cannulas, veno-arterial extracorporeal membrane oxygenation (va-ECMO) or extracorporeal life support (ECLS) has been widely used in emergency medicine and intensive care medicine for several years. An accepted indication is peri-interventional cardiac failure in cardiac surgery (postcardiotomy low cardiac output syndrome). Furthermore, especially the use of va-ECMO for other indications in critical care medicine, such as in patients with severe sepsis with septic cardiomyopathy or in cardiopulmonary resuscitation has tremendously increased. The basic indications for va-ECMO are therapy refractory cardiac or cardiopulmonary failure. The fundamental purpose of va-ECMO is bridging the function of the lungs and/or the heart. Consequently, this support system does not represent a causal therapy by itself; however, it provides enough time for the affected organ to recover (bridge to recovery) or for the decision for a long-lasting organ substitution by a ventricular assist device or by transplantation (bridge to decision). Although the outcome for bridged patients seems to be favorable, it should not be forgotten that the support system represents an invasive procedure with potentially far-reaching complications. Therefore, the initiation of these systems needs a professional and experienced (interdisciplinary) team, sufficient resources and an individual approach balancing the risks and benefits. This review gives an overview of the indications, complications and contraindications for va-ECMO. It discusses its advantages in organ transplantation and transport of critically ill patients. The reader will learn the differences between peripheral and central cannulation and how to monitor and manage va-ECMO.

Acute decompensated heart failure (ADHF) is a major public health problem throughout the world and its importance is continuing to grow. More than 50% of ADHF patients have coronary artery disease, which is generally associated with a history of hypertension. Recent data suggest that half of the patients presenting with acute heart failure have preserved left ventricular systolic function. The diagnosis of ADHF may be difficult at times, and the clinical assessment and patient profiling is essential for appropriate therapy. Immediate therapeutic goals are not only to improve symptoms, restore oxygenation and stabilize hemodynamic conditions, but also to improve short- and long-term survival. In addition to general supportive measures such as oxygen supplementation, noninvasive ventilation, analgesia, diuretics, vasodilators together with inotropic agents and/or vasopressors remain the cornerstone of therapy in patients with ADHF.

Background and Aim: Previous studies have found a similarly impaired prognosis in patients with heart failure with preserved ejection fraction (HFpEF) as in patients with systolic heart failure (HFrEF). This study examines the prognosis of HFpEF patients with only mild symptoms and compares two different methods of diagnosing HFpEF., Methods: Of 670 consecutive patients presenting in our outpatient clinic (57.6 ± 16 years, 50.1 % male), 165 revealed a typical clinical presentation with heart failure NYHA class II-III. The following echocardiographic parameters were assessed: ejection fraction (EF), left atrial size (LA), early and late antegrade mitral flow (E and A), early mitral annular movement (E'). Criteria for HFrEF were typical symptoms (NYHA II-III) and an EF < 50 %, HFpEF was diagnosed in patients with typical presentation, NYHA ≥ 2 and EF ≥ 50 % using 2 different definitions: similarly to the criteria of the I-Preserve study or as recommended by the german association of cardiology (DGK) that imply prove of diastolic dysfunction. Patients were followed-up for up to 2.5 years (mean 1.7±0.7) and the following events were registered: death, hospitalisation (myocardial infarction/coronary intervention/cardiac decompensation), cardiac transplantation (HTX)., Results: The majority (93.3 %) of the 165 heart failure patients had mild symptoms NYHA II. Of the 165 patients with typical symptoms, systolic heart failure could be found in 51 (30.9 %) and HFpEF according to I-Preserve criteria in 114 (69.1 %) patients. 56 (33.9 %) patients fulfilled the DGK criteria for HFpEF. Patients with HFpEF were significantly older, more often obese, female and hypertensive. The event rate was higher in patients with systolic heart failure (32 events, 62.7 %) than in patients with HFpEF (I-PRESERVE criteria: 28 events, 24.6 %; DGK criteria: 16 events, 28.6 %; both p < 0,001, log-rank), whereby this difference was mainly caused by increased hospitalisations (43.1 vs. 14.9 and 21,4 %, p < 0.001 and p < 0.016). Significantly more patients with HFrEF reached the combined end point death/HTX (p = 0.019 [I-Preserve] and p = 0.022 [DGK]). Both HFpEF groups showed no significant difference in any of the event types., Conclusion: Patients with HFpEF and mild symptoms have a more benign prognosis than those with systolic heart failure. Whether additional echocardiographic measurements are valuable for the diagnosis of HFpEF has to be proved in larger studies., (© Georg Thieme Verlag KG Stuttgart · New York.)

Patients suffering from septic shock often present with not only severe reduction of afterload induced by vasodilation but are also affected by sepsis-induced cardiac dysfunction. Elevated troponin levels, which are typically not caused by coronary ischemia, may indicate septic cardiomyopathy which is characterized both by altered systolic function as well as by disturbances in the regulation of heart rate and heart rate variability. The latter findings are based not only on the dysfunction of the autonomous nervous system but are also the result of the direct interaction of endotoxins with cardiac pacemaker cells. In order to quantify the extent of septic cardiomyopathy, cardiac output has to be considered in the light of the existing afterload, i.e., by the parameter 'afterload-related cardiac performance' (ACP). Therapy of septic shock (and thereby septic cardiomyopathy) is based on the well-known causative, supportive, and adjunctive strategies. Stabilization of cardiac function is assured by volume resuscitation (including blood transfusion) and inotropic support (dobutamine). Further specific therapeutic approaches have not yet been established.

Besides optimal drug therapy, cardiac resynchronisation therapy offers a further therapy option for selected patients. Additional ICD implantation should be evaluated as well to prevent sudden cardiac death.

As the population of elderly people is increasing, the number of patients requiring hospitalization for acute exacerbations is rising. Traditionally, these episodes of hemodynamic instability were viewed as a transient event characterized by systolic dysfunction, low cardiac output, and fluid overload. Diuretics, along with vasodilator and inotropic therapy, eventually became elements of standard care. In a multicenter observational registry (ADHERE--Acute Decompensated Heart Failure National Registry) of more than 275 hospitals, patients with acute decompensated heart failure were analyzed for their characteristics and treatments options. These data have shown that this population consists of multiple types of heart failure, various forms of acute decompensation, combinations of comorbidities, and varying degrees of disease severity. The challenges in the treatment require multidisciplinary approaches since patients typically are elderly and have complex combinations of comorbidities. So far only a limited number of drugs is currently available to treat the different groups. Over the past years it was shown that even "standard drugs" might be deleterious by induction of myocardial injury, worsening of renal function or increasing mortality upon treatment. Therefore, based on pathophysiology, different types of acute decompensated heart failure require specialized treatment strategies.

The treatment of progressive and terminal heart failure follows the principle of causative therapy. Therefore, etiology and pathophysiology of the underlying disease and its hemodynamic conditions are indispensable. This applies to coronary artery disease, hypertension, valvular heart disease, the cardiomyopathies with and without inflammation, and microbial persistence similarly. The classic treatment algorithms both in heart failure with and without reduced ejection fraction are based on measures onloading the heart (angiotensin-converting enzyme inhibitors, angiotensin antagonists, beta-blockers, diuretics) and on antiarrhythmics and anticoagulation, when needed. Device therapy for cardiac resynchronization in left bundle branch block and permanent stimulation therapy may contribute to the hemodynamic benefit. ICD (implantable cardioverter defibrillator) therapy prevents sudden cardiac death, which is often associated with progressive heart failure. Heart transplantation and left ventricular assist devices are final options in the treatment repertoire of terminal heart failure.

The non-invasive ventilation (NIV) has been practiced successfully for years in the clinical routine. Now this therapeutic option should be transferred in the pre hospital emergency service. But there are many risks, they must be mentioned: As a matter of fact an effective clinical therapy can not be brought to the streets easily - even if there are good and well-tried conservative therapies and just at last just a few patients.

Arterial hypertension is the leading cause of mortality and morbidity with a worldwide prevalence of 26%. Aging increases the incidence of arterial hypertension. Arterial hypertension is the prime example for a chronic disease with asymptomatic beginning, creeping course and fatal outcome. Arterial hypertension is a major cardiovascular risk factor and leads to vascular as well as myocardial manifestations: coronary artery disease, hypertensive microvascular disease, concentric left ventricular hypertrophy as well as perivascular and interstitial fibrosis. In the late stages of the disease, hypertrophy and cardiac failure develop. Arterial hypertension is the leading cause of coronary artery disease and cardiac failure, and coronary artery disease is the cause of heart failure in 50% of cases. Various non-invasive and invasive procedures are available for screening and follow-up. The primary therapeutic target is to reverse cardiac manifestations of arterial hypertension using specific therapeutic algorithms as well as lowering blood pressure. This article covers the pathophysiology of arterial hypertension and cardiac failure, clinical symptoms, diagnostic options and therapeutical goals as well as medicinal options.

Since 1st October 2003 the new German "Approbationsordnung für Arzte" (Medical Licensing Regulations) requires an increasing amount of small group teaching sessions and encourages a multidisciplinary and more practical approach to the related topics. In 2004 the German Society of Anaesthesiology and Intensive Care Medicine has provided almost all anaesthesia faculties of German Universities with equipment for full-scale simulation. This article describes methods for a simulation-based medical education training program. Basic requirements for a successful training program using full scale simulators are the provision of an adequate logistical and material infrastructure, teacher attendance of train-the-trainer courses, implementation in the medical curriculum and an instructor-student ratio of 1:3, equivalent to that for bedside teaching. If these requirements were fulfilled, medical students scored the simulation scenarios "induction of anaesthesia", "acute pulmonary embolism", "acute management of a multiple trauma patient" and "postoperative hypotension" as 1.5, 1.6, 1.5 and 1.5, respectively, on a scale of 1-6. These scores were better than those given for other segments of the curriculum.

Acute heart failure and especially its most severe form, cardiogenic shock, remain the final common pathway to death in a substantial number of patients with acute myocardial infarction (MI). Several studies demonstrated that mechanical reperfusion of occluded coronary arteries by percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery improves survival in patients with acute MI and cardiogenic shock. There is strong evidence that intraaortic balloon pump (IABP) support and ventricular assist devices can stabilize hemodynamics in these patients so that revascularization procedures can be safely performed. This article provides an overview of the therapeutic strategies for acute MI with cardiogenic shock, with focus on the role and particularities of different devices used as mechanical circulatory support in these patients.

The problem of sudden cardiac death (SCD) is complex and many questions concerning the pathophysiologic mechanism are still unanswered. At present the only reliable way of recognizing high risk patients is by means of left ventricular dysfunction, measured as LV-EF

Acute heart failure is always an indication for referral to an intensive care unit. In the widest sense, the term acute heart failure includes the manifestation forms of pulmonary edema, cardiogenic shock or rapid-onset decompensated cardiac insufficiency unaccompanied by shock or pulmonary edema (low-output syndrome). Acute heart failure may occur in the absence of previously known heart disease. Existing prior specific diseases that may end in acute cardiac insufficiency include acute myocardial infarction, decompensated cardiomyopathy, myocarditis, cardiac tamponade, endocarditis or arrhythmogenic heart failure.

The beneficial hemodynamic effects of cardiac resynchronization in patients with intraventricular conduction delay have been demonstrated. The potential hemodynamic effects of cardiac resynchronization to compensate the pacing-induced left ventricular conduction delay in chronically paced heart failure patients are not as well established. The aim of the study was to evaluate the acute hemodynamic effects of biventricular and left ventricular pacing in chronically paced patients with advanced heart failure. Fourteen consecutive pacemaker or defibrillator patients with permanent atrial fibrillation and AV block (11 male, 3 woman, mean age: 68 +/- 7 years) were enrolled in this study. There were 5 ischemic (36%) and 9 nonischemic (64%) patients (mean left ventricular ejection fraction: 19 +/- 5%; mean end-diastolic left ventricular diameter: 71 +/- 11 mm). In all patients a right ventricular and left ventricular (via coronary sinus) pacing lead was placed. The aortic and left ventricular hemodynamic measurements were performed using a two-channel micro-tip catheter. The measurements of the aortic pulse pressure (APP) and (dP/ dtmax) were performed during right ventricular apical pacing (RVP), left ventricular (LVP), and biventricular pacing (BVP) (70 bpm). Compared to RVP, LVP and BVP increased APP and dP/dtmax (35.8 +/- 4.2 vs 43.3 +/- 4.5 and 41.2 +/- 4 mmHg; p < 0.001) and (758 +/- 56 vs 967 +/- 60 and 961 +/- 62 mmHg/s; p < 0.001). LVP and BVP showed a comparable hemodynamic response. The hemodynamic effects were not related to the width of the paced QRS complex. Every patient showed improved hemodynamics during LVP and BVP unrelated to the underlying heart disease and to the baseline level of left ventricular dysfunction. BVP and LVP pacing acutely improve contractile left ventricular function in chronically paced patients with advanced heart failure.

Today, an increasing number of old and very old patients is referred for invasive cardiovascular procedures. At our institution, cardiac catheterization has been performed in 82 patients 80 years of age or older (50 m, 32 f; mean age 82 +/- 2 years) during the last 11 years; in 70 patients, because of clinically proven or suspected coronary heart disease, and in 12 patients, because of heart valve disease. In comparison with younger patients, elderly patients with coronary heart disease more often presented with unstable angina, or had multivessel disease and reduced ejection fractions. PTCA (n = 25) and bypass grafting (n = 7) aimed at revascularization in 32 patients; in 38 patients, medical treatment was continued. Furthermore, valve replacement (n = 7) or valvuloplasty (n = 1) were judged to be indicated in 8 of the 12 patients with heart valve disease. Diagnostic procedure was more frequently burdened with serious complications in elderly than in younger patients (5/82 versus 3/300, p < 0.01). During follow-up of 25 +/- 23, median 21 months, cardiovascular events were significantly less frequent in patients with coronary heart disease who had undergone revascularization procedures than in those with medical therapy (2/29 versus 9/36; p = 0.05); more revascularized patients were free of angina at the time of reevaluation. Thus, risks of invasive diagnostic procedures are increased in very old patients. Diagnostics, however, result in therapeutical consequences, revascularization obviously improves symptomatology and prognosis in patients at extremely advanced age suffering from coronary heart disease.

Between April 1988 and February 1995, 35 patients aged 80 years or older underwent elective coronary artery bypass grafting. Concomitant aortic valve replacement was performed in eight patients. Fifteen patients with moderate to severe left ventricular dysfunction (left ventricular ejection fraction (EF) 20 to 45%) (group I) were compared to 20 patients with an EF > 45% (group II). There were no differences according to age, NYHA classification and associated diseases. Group I patients had significantly more myocardial infarctions compared to group II (1.3 +/- 1.1 vs. 0.5 +/- 0.8; p < 0.05). Also more bypass grafts per patient were used in group I (3.1 +/- 0.9 vs. 2.3 +/- 0.9; p < 0.01). No differences between the groups were observed in the postoperative course. One patient of group II died from multiorgan failure (hospital mortality 2.2%). A follow-up could be performed in 32 of 34 hospital survivors (94%) 12.0 +/- 11.2 months (1-41 months) postoperatively. There was one non-cardiac death in each group. All hospital survivors improved by at least one NYHA functional class. Actuarial survival at 3 years is 91% in both groups. In patients aged 80 years or older with or without left ventricular dysfunction coronary artery bypass surgery can be performed with an acceptable risk and a functional benefit. Thus, elective operations should be performed in this age group despite left ventricular dysfunction.

In cardiac surgery, ventricular assist devices for mechanical circulatory support are implanted for short or mid-term use in patients with therapy refractory postoperative low-output-syndrome to overtake the function of the left, right or of both ventricles until recovery of myocardium can be achieved. In the long-term, these systems are in use as a bridge to transplantation. An increasing number of clinical reports clearly demonstrates that ventricular assist devices can guarantee in a relatively high percentage of patients with postoperative low-output-syndrome a sufficient regeneration of the cardiac function with satisfactory functional and hemodynamic long-term results. Furthermore, a high percentage of patients bridged to transplantation can be successfully transplanted with good clinical outcome and survival rates.

In cardiac surgery mechanical circulatory support with intra-aortic balloon counterpulsation (IABP) is an established measure for the therapy of perioperative low-output-syndrome and refractory cardiogenic shock. The favourable influence on the myocardial oxygen supply and demand-relationship with an improvement of the energetic balance guarantees the functional and ultrastructural recovery of reversibly damaged ischemic myocardium. The efficacy of IABP is uncontradicted and verified by high survival rates even in patients with severe impairment of the ventricular function. The system is easy to applicate by standardized surgical techniques of im- and explantation, safely to handle due to improvements of the technical equipment and can be applied at a low risk.

The present definitions of low-output syndrome (LOS) associated with cardiac surgery are based on data obtained via the Swan-Ganz-catheter. However, further important data such as signs of chronic renal insufficiency, arterial vascular disease, and perioperative volume overload have hardly been considered. At the Heart Center NRW, FRG, the Swan-Ganz-Catheter is not used routinely to monitor patients following cardiac surgery. According to our experience, the definition of low-output syndrome includes a wider spectrum of relevant criteria. In addition to the data obtained by means of a central venous catheter the clinical aspect of the patient as well as laboratory analysis should be regarded as well. In 1259 consecutive patients (pts) (914 with coronary surgery and 318 with valve surgery) the incidence and mortality of low-output syndrome were determined. In 49 of the 941 coronary surgery pts (5.2%) a postoperative low-output syndrome occurred. Nine pts (0.95%) died as a result of this complication. According to our therapeutical strategy, the low-output syndrome was treated medically in 28 pts (2.9%); in 14 pts (1.5%) IABP implantation was necessary, and 7 pts needed mechanical circulatory support. Surprisingly, the same incidence of LOS occurred in the valve surgery group of pts as in the coronary group. We saw a low-output syndrome in 17 of the 318 pts (5.3%), with fatal outcome in three pts. In 14 of these pts (4.4%) the LOS was treated medically, while the remaining three pts (0.9%) required diastolic augmentation of the IABP.

In a 21-month-old child with complex cyanotic congenital heart disease an aortopulmonary shunt was created as preparation for a modified Fontan operation. During the early postoperative period low cardiac output with right atrial pressures of 20 mm Hg developed due to a slow ventricular tachycardia (ventricular rate 135 bpm). Pharmacological interventions (isoprenaline 0.01 mg/kg hourly and lidocaine 1 mg/kg hourly were without any effect. As epicardial pacing leads had not been implanted during surgery, atrial pacing was performed via the transoesophageal route using a 9.5-F bipolar electrode catheter with an interelectrode distance of 15 mm. Atrial capture could be established with an impulse width of 9.9 ms and 10 mA output at a rate of 150 bpm. With restoration of atrioventricular synchronicity, right atrial pressure finally decreased to 10 mm Hg with consecutive stabilization of the cardiovascular status. After 12.5 h transoesophageal pacing could be stopped without any problems due to spontaneous cessation of ventricular tachycardia. No clinical signs of oesophageal injury were noted. It is concluded that transoesophageal pacing is a practical, safe and effective method for emergency cardiac pacing.

Among nearly 2000 consecutive PTCA-patients 42 (36 male, six female; mean age 60 +/- 11 years) had ejection fractions < or = 35% (mean 30 +/- 5%). 34 patients suffered from unstable and eight from stable angina. All had previous myocardial infarction and of these 23 had recent myocardial infarction. Four patients had prior coronary bypass surgery and one had undergone aneurysmectomy. 31 of 42 (= 74%) patients had multiple vessel disease (stenoses > 50%). Successful procedure was achieved in 35 of 42 patients (= 83%). The lesion-related success rate of PTCA was 89%, of recanalization 60%. Six procedures were multiple vessel PT-CA. Major complications occurred in two of 42 patients (one myocardial infarction, one emergency bypass operation). The in-hospital mortality was 2.4%. Follow-up angiography was performed in 22 patients and showed restenoses in nine cases. All patients underwent repeat coronary angioplasty, of these one patient had postprocedural myocardial infarction. The ejection fraction had meanwhile significantly improved from 29 +/- 5% to 36 +/- 7%. Clinical follow-up after 18 +/- 14 months (two to 53 months) was available in 39 of 40 patients, who were discharged from hospital without major complications. 29 patients were free of angina or anginal class II, one had a late cardiac transplant. Five patients had died of cardiac and one of noncardiac causes. Thus, PTCA in patients with severely depressed ventricular function shows acceptable acute results, which are comparable to those of routine angioplasty, continued symptomatic improvement can be achieved. However, the late outcome is significantly worse than in patients with normal left ventricular function.

Perioperative circulatory disorders in patients may take the form of a transitory reduction in oxygen transport to the peripheral tissues (pre-shock), manifest circulatory insufficiency in the presence or absence of concomitant heart insufficiency or general congestive heart failure due to the destabilization of an preexisting heart disease. The least problematical stage in this programme of therapy is the treatment of transitory perioperative circulatory insufficiency by manipulation of the oxygen transport system using the following means: comparative volume optimization [according to the central venous pressure (CVP)], positive inotropic support with dobutamine (5-10 micrograms.kg-1.min-1), monitoring of the blood pressure, heart rate and oxygen consumption and, in severe cases, insertion of a Swan-Ganz catheter. In manifest circulatory insufficiency, sepsis or acute congestive heart failure, the Swan-Ganz catheter seems to be obligatory. In such cases, the positive inotropic therapy is based on catecholamines of medium (dobutamine) or high (epinephrine) positive inotropic efficacy, as a normal pattern and functioning of beta-adrenoceptors can be assumed in such cases if there is no history of cardiac insufficiency. The systemic vascular resistance (SVR) is adjusted to 800-1200 n.s.cm-5 to relieve the working capacity of the heart and to maintain sufficient perfusion pressure by means of constrictors (phenylephrine, norepinephrine) or dilators [nifedipine, nitroglycerin or, if necessary, angiotensin-converting-enzyme (ACE) inhibitors].(ABSTRACT TRUNCATED AT 250 WORDS)

Low cardiac output can be encountered after corrective surgery for complex congenital malformation in children and infants and is often accompanied by an impairment of renal function, ascites, hyperosmolarity and hyperpyrexia. In most instances, combined afterload-reduction and inotropic stimulation will be effective. If low cardiac output persists, a peritonealdialysis (PD) may allow correction of fluid balance and consecutive improvement of hemodynamics. During a 18 month-period, PD was performed in 14 children in the postoperative period following major cardiac surgery (transposition 5, Fallot tetralogy 5, various complex anomalies 4). This represents 3.1% of all cardiac operations performed in children with congenital heart disease throughout the same period. There were 8 males and 6 females with a median age of 2.5 years (range 3 days to 4 years) and a median bodyweight of 5.5 kg (range 3.4 to 10 kg). Low cardiac output was defined when two or more of the following factors were met: mean arterial pressure (MAP) below 40 mm Hg despite inotropic stimulation, central venous pressure (CVP) over 15 mm Hg, urine production less than 1 ml/kg/hour and/or increasing transaminases. Before starting peritoneal dialysis all children received combined positive inotropic and vasodilative therapy. The PD-catheter was introduced 8 to 30 hours after operation. We used a PD-solution with 1.5% and/or 4.5% glucose. Fluid balance was monitored hourly. Just after introduction of the catheter a mean of 65 ml +/- 25 ml/kg ascites could be removed and the total quantity of removed fluid was 175 ml +/- 45 ml/kg bodyweight.(ABSTRACT TRUNCATED AT 250 WORDS)

The postoperative course of 95 patients following esophagectomy was analyzed with regard to the occurrence of cardiac arrhythmias and circulatory instability. In 86 subjects (90%), post-operative atrial and ventricular arrhythmias were recorded. In all, 29 patients (30%), showed hypotonic episodes, with arterial mean pressures of less than 65 mmHg being recorded. Preloading was reduced in 8 cases, as was afterloading in 16 subjects, whereas in 5 patients actual cardiac failure occurred. There was a strong correlation between circulatory instability and postoperative surgical complications. All 24 subjects who developed surgical complications (that is, 80% of all patients exhibiting circulatory instability) experienced hypotonic episodes. In this group of patients, management should consist of a rational combination of vasoactive substances together with surgical removal of the focus. This analysis supports our proposition that in postoperative instability, one should always suspect initial, actual surgical complications and initiate adequate diagnostic and therapeutic measures.

The model of the failure of the right ventricle was formed in dog experiments. The animals were connected with the right mechanically assisted circulation. The blood was pumped synchronously with the heart action from the right atrium directly to the pulmonary artery by temporary bypass of the right ventricle. The right volume relief improved (p less than 0.03) the decisive hemodynamic parameters. The value of assisted circulation in case of the hitherto only difficulty to controlled failure of the right ventricle is proved with that.

At the present time mechanical assisted circulation is indicated in patients with cardiac failure after open heart operations. The results after clinical implantation of the left ventricular assist devices are not encouraging. However, most of these patients suffer from irreversible cardiac failure and no restitution is to be expected. In patients with postoperative cardiac failure, a distinction must be made between isolated left heart failure and total heart failure. In patients with total heart failure - for example with diffuse, marked coronary sclerosis - both left and right ventricle failure exists. In these patients, no left ventricular assist device per se can bring the desired effect, since due to the right heart failure syndrome, the left system does not work adequately. With the biventricular bypass it is possible to maintain complete circulation in cases of cardiac insufficiency. The cannulation concept is biventricular transatrial to the aorta or to the pulmonary artery. The technique is simple and can be carried out very quickly. In cases of clinical emergency this device can be recommended due to the satisfactory haemodynamic effects achieved and the small degree of traumatic haemolysis. It represents an easy and quick implantable system for total functional heart replacement.

A case report is given on a new method for treatment of drug-resistant slow ventricular tachycardias by automatic dynamic overdrive stimulation, using an implantable pacemaker system. In a 60-year-old patient with coronary heart disease and ventricular tachycardia refractory to drug therapy, an antitachycardia Medtronic pacemaker (type SP 0501) was implanted in October 1984 and used successfully in 65 attacks during 13 months. However, when trying to terminate the tachycardia by means of programmed stimulation, acceleration of the ectopic ventricular rate occurred at 8 occasions. The administration of the experimental antiarrhythmic drug diprafenone (Class Ic) resulted in a reduction of the ventricular frequency but not of the rate of attacks. Then the Vitatron Quintech DDD pacemaker was implanted, providing the chance of terminating the now reduced ventricular rate by the dynamic overdrive mode.