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The implantable cardioverter-defibrillator (ICD) was a breakthrough in the prevention of sudden cardiac death. After years of technical development in the USA, Michel Mirowski succeeded in proving reliable automatic defibrillation of ventricular tachyarrhythmias through initial human implantations in 1980, despite many obstacles. Nearly 4 years later, the first patients received ICDs at multiple centers in Germany. Subsequently, outside the USA, Germany became the country with highest implantation rates. The absolute number of implantations remained small as long as implantations required epicardial defibrillation electrodes and therefore thoracotomy by cardiac surgeons. Pacemaker-like implantation using a transvenous defibrillation electrode with a pectoral ICD became feasible in the early 1990s pushing implantation rates to the next level. Technical advancements were accompanied by clinical research in Germany, and often, the first-in-human studies were conducted in Germany. In 1991, the first guidelines for indications were established in the USA and Germany. Several randomized studies on indications were published between 1996 and 2009, mostly led by American teams with German participation, but also under German leadership (CASH, CAT, DINAMIT, IRIS). The DANISH study in 2016 questioned the results of these long-standing studies. Instead of providing ICDs to patients using a broad indication, future efforts aim to identify patients who, despite optimal medical therapy, cardiac resynchronization therapy (CRT), and/or catheter ablation, need protection against sudden cardiac death. Risk scores incorporating myocardial scars in magnetic resonance imaging (MRI) and genetic information are expected to contribute to more individualized and effective indications., (© 2024. The Author(s).)

Background: Stroke and dementia have several modifiable risk factors in common. In the primary care prevention project INVADE (INtervention project on VAscular brain diseases and Dementia in the district of Ebersberg), these vascular risk factors were recorded systematically and treated according to evidence-based guidelines., Methods: All insurants of the AOK Bayern who were ≥ 50 years of age and lived in the Upper Bavarian district of Ebersberg received the offer to participate in INVADE, about one-third enrolled in the program. Examinations by the family doctor, self-reports of the participants, laboratory analyses, and a duplex sonography of the extracranial neck vessels were used to create individual risk profiles, from which the intervention measures were derived. GPs documented the treatment and health status of the participants at quarterly intervals. The entire examination program was repeated every two years. The success of the intervention was determined in comparison with the district of Dachau, where the insurants received the primary care treatment as usual. Administrative data of the health and long-term care fund for the period from 2013 to 2016 were used as clinical endpoints. Primary endpoints included mortality and onset of long-term care, secondary endpoints were inpatient treatments due to cerebrovascular disease., Results: The comparison between the district of Ebersberg (N = 10.663) and the district of Dachau (N = 13.225) was in favor of the prevention program for both the primary clinical endpoints and the combined secondary endpoint. Mortality risk (HR = 0.90; 95 % confidence interval: 0.84-0.97), long-term care risk (HR = 0.88; 0.81-0.96), and the likelihood of inpatient treatment for cerebrovascular disease (OR = 0.87; 0.77-0.97) were significantly reduced., Conclusions: The results support the assumption that the incidence of cerebrovascular disease and dementia can be reduced by a systematic general-practice based identification and treatment of vascular risk factors and can thus increase life expectancy and disability-free life time., Registration: clinicaltrials.gov, NCT1107548, registration date: 21.04.2010, drks.de, DRKS00011348, registration date: 29.12.2016., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Community participation, recognised as a central feature of successful health promotion and prevention, is often difficult to implement. In this research project internationally recognised methods of participatory health research were applied to demonstrate ways in which community members can be engaged. Participatory health research is characterised by a close collaboration between academic researchers, practitioners and community members in order to generate common knowledge. It is not a question of translating knowledge from research into practice, but rather a question of promoting a collective learning process on the part of all participants for the purpose of developing solutions which address the interests and needs of local people. The result of the project is a new approach for strengthening the quality of prevention and health promotion interventions: participatory quality development (PQD)., (© Georg Thieme Verlag KG Stuttgart · New York.)

Two young patients with documented episodes of symptomatic paroxysmal atrial fibrillation have been referred for pulmonary vein isolation. Both patients had a history of concomitant regular tachycardia. in both cases pulmonaryvein isolation has not been performed but in each patient a supraventricular tachycardia (right focal atrial tachycardia/atrioventricular reentry tachycardia) could be induced and ablated instead. Concomitant supraventricular tachycardia acting as a trigger arrhythmia is frequent in young patients with atrial fibrillation without underlying cardiacdisease. In these patients a concomitant supra-ventricular tachycardia should beexcluded by electrophysiological study or ablated before pulmonary vein isolation or initiating an antiarrhythmic drug therapy. In most cases ablation of supraventricular tachycardia is safe and successful whereas the risks of ablative therapy of atrial fibrillation can not be neglected and success is moderate.

The intrinsic connection between empowerment and participation is apparent in the Ottawa Charter on Health Promotion. In order for citizens to reach a higher degree of autonomy and control over health-related factors (empowerment) they need to have an active role in the decision-making processes affecting their lives and the environment in which they live (participation). This implies that many decisions are made affecting the health of citizens over which they have no influence. The question is: Who has the power to make such decisions and how can this power be shared more equitably? This question can be raised not only at the highest political level, but also locally in the context of the collaboration between various stake-holders. The local level plays a key role in deciding which health promotion measures are developed and funded, thus contributing in an important way to strengthening communities. In this article the method "Circles of Decision-Making" is presented as a tool for assisting those working at the local level in determining to what degree the active participation of the various stake-holders has been achieved and in what ways the participation of those "on the outside" of decision-making processes can be strengthened. This method is based on the concept of Participatory Quality Development (PQD) created by the authors and their community partners. PQD uses methods from community-based research to address issues of quality in community-level health promotion and prevention.

Infections of implantable cardioverter defibrillators (ICD) are severe, potentially life-threatening complications of ICD therapy. In the majority these infections are nosocomial by staphylococci, which become apparent within 0.5 years after implantation. Prophylaxis requires a strictly sterile environment during implantation and perioperative antibiotics. While infection of the ICD pocket is diagnosed clinically, infection of the electrodes must be proven by transesophageal echocardiography and positive blood cultures. Therapeutically, the complete ICD system has to be removed to avoid relapses of infection. Beyond 6 months after implantation, lead extraction might become technically demanding and should be done with a standby of cardiac surgery. Antibiotic treatment has to be started before removal of the system, continued for at least 2 weeks before reimplantation and for another 10 days thereafter. Reimplantation should be done outside the originally infected area.

Severe cardiac insufficiency with a clearly diminished contraction of the left ventricle is often accompanied by a pronounced left bundle branch block in the EKG. The early and late activated sides of the ventricular walls contract asynchronously, further decreasing the cardiac output. Resynchronization can be achieved through a biventricular pacemaker, which simultaneously stimulates the early and late sides of the ventricular walls. In addition to the electrode usually placed in the tip of the right ventricle, a second electrode is placed on the lateral wall of the left ventricle. This normally leads to an immediate small increase in the blood pressure and to an increased functional capacity. For patients with asynchrony of the left ventricle, an improvement of the cardiac insufficiency by approximately a half of an NYHA class and a decrease in the yearly mortality by 4% has been documented.

Microbe-induced (infectious) endocarditis is an endovascular infection, caused mainly by bacteria, of cardiovascular structures. The major predilection site are the native heart valves, but involvement of implanted intracardiac foreign material is increasingly being seen. The mortality rate of infectious endocarditis depends on clinical factors and the causal agent, but also on the time of the establishment of the diagnosis and the initiation of appropriate treatment. In Germany, the current mortality rate ranges up to 18%. Between January 2003 and July 2004, with the aim of improving patient care and thus the outcome of this condition, a guideline commission worked out recommendations for the diagnosis, treatment and management of the disease for the use of general practitioners and hospital physicians, in particular microbiologists, infectiologists, cardiologists and cardiac surgeons. The basis for this guideline was the systematic search through the literature of the European guideline. On the 16th and 28th of June 2004, the entire guideline was formerly approved in a nominal group process.

In patients with congestive heart disease in whom left ventricular dilatation is associated with severely disordered contraction due to delayed ventricular conduction, a new form of treatment not requiring drugs is currently becoming established--biventricular pacing. Via an implanted electrode, biventricular stimulation accelerates conduction in the left ventricle and resynchronizes its contraction. Patients being considered for such therapy must have stable stage III disease (NYHA classification) under optimal medication, and a left bundle branch block with a QRS of at least 150 ms. Definitive recommendations with regard to indications will be possible only when current randomized mortality studies have been concluded.

All 181 patients with malignant arrhythmias who have been provided with an implantable cardioverter-defibrillator (ICD) at the University Clinics of Muenster during the last 3 years, were investigated by a clinical questionnaire on quality of life (QOL). 132 patients answered and could be included in the study (response rate 73%). The mean age of the patients was 55 +/- 11.8 years, 73% males, 60% had already retired. In the general view 51% of the patients reported fair to excellent quality of life, while 24% gave a negative description of their QOL. 26% of the patients suffered from side-effects of the treatment, primarily from unspecific psychological complaints and ICD-related disturbances. "Unrest" was the predominant psychological complaint (64% of the patients), followed by rumification, shortness of breath, weakness and sleep disturbances. Somatic function and sex life were the functional areas primarily affected (more than half of the patients complaining about these). The "Psychological General Well-Being Index (PGWB)" showed reduced well-being in 61% of the patients. Comparing with the literature and regarding the PGWB-scales well-being, anxiety, and depression no significant differences could be found in comparison with other cardiologic samples after bypass-surgery or valve replacement. The results indicate the need of individual counseling and offers of psychosocial support for this highly strained group to reduce anxiety and to improve the quality of life in order to help the patient to gain greater overall benefit from the new ICD-therapy.

Postoperative tests of implantable cardioverter defibrillators (ICDs) are routinely performed to ensure appropriate defibrillation by the device. However, efficacy and complications of this procedure are unknown. To scrutinize the currently accepted indications to test the defibrillation function of the ICD we retrospectively analyzed 844 ICD-tests in 439 ICD-systems and 409 patients. 755 ICD-tests (89.4%) were routinely performed (57% before discharge and 43% during follow-up); 58 tests (6.9%) were performed after a change of the antiarrhythmic drug regimen, 24 tests (2.9%) after a revision of a part of the ICD-system, and seven tests (0.8%) because of a suspected dysfunction of the ICD. During routine-tests six ICD-systems (0.8%) failed to defibrillate the patient. However, in all but one test abnormalities of the ICD-system had been observed before the test. After addition of antiarrhythmic drugs, three of 58 ICD-systems (5.2%) failed to defibrillate the patient during the test (amiodarone: n = 2, flecainide: n = 1). Four of seven ICD-systems (57%) tested due to a suspected dysfunction failed to defibrillate the patient. After revisions of parts of the ICD-systems, ICD-tests never revealed a failure of defibrillation. During 16 ICD-tests (1.9%) complications occurred. The most frequent complications was inappropriate shocks (n = 10; 1.2%), the most severe one (transient) neurologic symptoms (n = 4; 0.48%). Our experience demonstrates that postoperative tests of the defibrillation function of ICDs rarely reveal ICD-dysfunction. As testing is unpleasant for the patient and not free of complications, tests might be restricted to those patients in whom an ICD-dysfunction is suspected (based on clinical presentation, results of chest-x-ray, testing of sensing signal and stimulation threshold) or class I or class III antiarrhythmic drugs have been added to the antiarrhythmic drug regimen.

The defibrillation threshold (DFT) is no threshold in the true sense. Between energy levels which defibrillate in all cases and energy levels which never defibrillate, a broad range of energies exists which might or might not defibrillate. Thus, the value of the DFT is dependant on the protocol used for its determination. Usually the DFT presents an energy at which the implantable cardioverter-defibrillator (ICD) will defibrillate successfully at a rate of approximately 75%. To achieve a 100% success rate the energy has to be programmed 15 J above the DFT or twice the DFT.Using DFT measurements the energy needed for internal defibrillation could be gradually reduced in the last years. Major break throughs have been the introduction of the biphasic defibrillation waveform and the use of pectorally implanted ICD shells as defibrillation electrodes. The shortening of the defibrillation impulse by the use of lower capacitances could not improve DFTs but allowed to construct ICDs of smaller volume. Addition of a superior vena cava electrode or a subcutaneous array electrode at the left lateral chest to the standard bipolar electrode system (right ventricle, pectoral ICD can) allowed for tri- and quadripolar lead configurations which reduced DFTs on average only slightly but reduced the standard deviation of DFTs significantly and thus helped to avoid high DFTs. Besides building smaller ICDs, reduction of DFTs and thus programming of lower defibrillation ICD energies allows for improved battery longevities and reduced capacitor charging times and thus a lower incidence of syncopes.

Patients with implantable cardioverter defibrillators (ICD) often suffer inappropriate ICD-therapies. The incidence, causes and risk factors of ICD-therapies for a rhythm other than ventricular tachyarrhythmias (VT) were determined retrospectively in 462 consecutive patients (pts). Inappropriate ICD-therapies were identified based on stored R-R intervals and/or electrograms. Eighty-two pts (18%) had inappropriate ICD-therapies. Actuarial rates for inappropriate ICD-therapies were 13%, 20%, 24% and 29% at 1, 2, 3 and 4 years after ICD-implantation, respectively. Atrial fibrillation with rapid ventricular response was the most common cause (34 pts, 39%). In 26 pts (30%), sinus tachycardia triggered inappropriate ICD-therapies, in 21 pts (24%) overseeing, mostly due to fractures and insulation failures of the leads, in three pts atrial flutter, in two pts non-sustained VT, in one pt supra-ventricular tachycardia and in another pt T-wave double sensing caused inappropriate ICD-therapies. In order to prevent recurrences of inappropriate ICD-therapies due to atrial fibrillation or sinus tachycardia, a rate stability (n = 19) or onset (n = 15) criterion was programmed, 41 pts additionally received beta-blocking agents and/or digoxin. In pts with overseeing an operative revision of lead system was performed. During further follow-up (15 +/- 13 months), 15 pts had recurrences of inappropriate ICD-therapies (eight pts due to atrial fibrillation, three due to sinus tachycardia and four due to overseeing). On multivariate analysis (Cox regression), history of atrial fibrillation, maximum heart rate during exercise and low cut-off rate for VT-detection were predictors of inappropriate ICD-therapies. Thus, inappropriate ICD-therapies are frequent, especially in the first year after implantation. Additional detection criteria, beta-blocking agents and/or digoxin prevent recurrences in most patients. In patients with a history of atrial fibrillation, high heart rate during exercise or a low cut-off rate for VT-detection, activation of additional detection criteria should be considered directly after ICD-implantation.

30 patients (mean age 51.4 +/- 11.6 years; female n = 6) were studied early after orthotopic heart transplantation (11.6 +/- 5.5 weeks). Twelve recipients had undergone specific treatment for biopsy proven rejection. Using a mechanical intravascular ultrasound device (3.5-F catheter), 153 coronary artery segments (16 left coronary main stem, 122 left anterior descending artery, 15 left circumflex artery) were studied. Intimal index and circumferential extension of a three-layer appearance of the vessel wall were assessed. In all segments, systolic-diastolic changes in area (delta A) with respect to vessel area and pressure (delta P) were used to study normalized compliance (normalized compliance = [delta A/A]/delta P [mm Hg-1 x 10(3)]). Intravascular ultrasound findings were correlated to perioperative ischemia time, LDL/HDL-ratio, Lp(a) and donor age. In a subgroup of 13 recipients, intravascular ultrasound investigation was repeated after an interval of 67.4 +/- 10.2 weeks. At first investigation, mean intimal index of all coronary segments was 0.07 +/- 0.10. Mean circumferential extension of a three-layer appearance of the vessel wall was 84 +/- 112 degrees. Normalized compliance was 2.43 +/- 1.90 mm Hg-1 in the left main stem 2.45 +/- 1.47 mm Hg-1 within the left anterior descending artery, and 2.66 +/- 1.72 mm Hg-1 within the circumflex artery (differences n.s.). No correlation was found between intimal index and normalized compliance (r = -0.322), nor between circumferential extension of intimal thickening and normalized compliance (r = -0.362). Furthermore, there was no correlation between normalized compliance and donor age. Normalized compliance was significantly lower in recipients with proven rejection than in those without (1.76 +/- 0.81 versus 2.95 +/- 1.22 mm Hg-1, p = 0.005). Both, intimal index and circumferential extension of intimal thickening, were significantly higher in recipients following rejection periods (p < 0.05). The extent of coronary vessel wall alterations on ultrasound correlated to donor age but not to perioperative ischemia time, LDL/HDL-ratio and Lp(a). Re-investigation of a subgroup of 13 recipients 67.4 +/- 10.2 weeks after the first study showed an insignificant increase of the intimal index (from 0.03 to 0.09) and of the circumferential extension of intimal thickening (from 40 to 111 degrees). Normalized compliance changed from 2.53 +/- 1.48 to 2.87 +/- 1.33 mm Hg-1 (differences n.s.). Early after orthotopic heart transplantation, a significant correlation between atherosclerotic coronary vessel wall alterations assessed by intravascular ultrasound and donor age can be confirmed. Heart recipients following rejection periods present with significantly more atherosclerotic vessel wall alterations and a severely reduced compliance of the coronary vessels.

Treatment strategies in patients with life-threatening ventricular tachyarrhythmias (i.e. sustained ventricular tachycardia, ventricular fibrillation, aborted sudden cardiac death) are changing. Amiodarone and d,l-sotalol, chosen by electrophysiologic study guidance, can be considered as drugs of choice for the pharmacological treatment. Compared to these agents, which both have additional electrophysiologic effects, the new pure class III agents seem to be less effective. With regard to antiarrhythmic efficacy, clinical trials comparing the long-term efficacy of antiarrhythmic agents and the implantable cardioverter/defibrillator are under way. Preliminary results indicate that the implantable cardioverter/defibrillator may provide superior outcome with regard to sudden cardiac death compared to the use of class III agents.

The depiction of atherosclerotic vessel abnormalities is a prerequisite for percutaneous interventional therapy and long-term observations of peripheral artery disease. The aim of this in-vitro study was to determine the potentials and limitations of 12.5 and 20 MHz intravascular ultrasound, computed tomography and magnetic resonance (MR) imaging in comparison to direct magnification radiography for the localization and quantification of peripheral vessel wall calcifications. Forty-three postmortem, human iliac segments were examined by intravascular ultrasound (12.5 and 20 MHz), computed tomography and magnetic resonance tomography (gradient echo-and spin echo-technique). For comparative analysis, each segment was divided into eight sectors of 45 degrees each; using all five methods, the presence of calcified wall areas was examined in each sector, and luminal area (42 segments) and plaque area (32 isolated plaques) were quantitatively estimated. In the sonograms, the circumferential extension of the boundary between intima and media was measured. 122 of 344 sectors showed regional vessel wall calcifications. Sensitivity of 20 MHz intravascular ultrasound was 73% versus 59% with the 12.5 probe, specificity was 97% with 20 MHz, 96% with 12.5 MHz. Sensitivity of both 12.5 and 20 MHz intravascular ultrasound was higher with increased thickness of the calcified structures. 20 MHz ultrasound identified the intima-media boundary averaging 146.8 degrees of the vessel circumference; the corresponding value of 131.8 degree with 12.5 MHz did not differ significantly. Computed tomography detected calcifications with a sensitivity of 88%, specificity was 88%. With MR imaging, sensitivity of the gradient echo-technique was 94% versus a sensitivity of 86% with spin echo-technique. Quantification of luminal and plaque areas showed that luminal area was precisely estimated only by 20 MHz ultrasound (no significant difference to direct magnification radiography), whereas all other techniques showed significant overestimation. Plaque areas were markedly overestimated by computed tomography and MR imaging, too. In an in vitro set-up, intravascular ultrasound, MR tomography and computed tomography do not allow an authentic depiction of peripheral vessel wall architecture. Limited resolution, subintimal shadowing and and distortion are the main limitations of these new techniques so that details of regional vessel wall calcifications cannot be presented thoroughly. Relevant over-estimation of luminal and plaque areas must be considered.

Ultimately, implantable cardioverter-defibrillators (ICD) will one day be implantable like present pacemakers. However, due to the size of the pulse generator and the low defibrillation efficacy of monophasic shocks, only a few selected patients have been implanted transvenously-pectorally. Therefore, we have prospectively investigated whether a transvenous-pectoral approach is in general feasible with a new downsized ICD capable of delivering biphasic shocks. Out of 33 patients, 76% received a bipolar transvenous defibrillation lead system. In the first 13 consecutive patients, a randomized crossover study showed that this high efficacy was above all achieved by a superior defibrillation efficacy of the biphasic waveform in comparison to the monophasic waveform (69% vs. 23%; p = 0.03). Not a single patient could be defibrillated exclusively with the monophasic waveform. In a further 15 consecutive patients, a crossover study showed that a position of the transvenous anode within the Vena anonyma instead of the Vena cava superior is, in general, not superior (87% vs. 80%; p = 0.67). Only one patient could be exclusively defibrillated with the V. anonyma position. Intraoperatively, no complications occurred and all but one patient received a pectoral implantation of the pulse generator. Postoperatively, in five patients local complications related to the ICD system were seen; two needed a surgical revision. In two patients movements of the left shoulder joint were temporarily restricted. Thus, in the majority of patients a new downsized ICD capable of biphasic shocks can be implanted transvenously-pectorally like a pacemaker.

For years the high efficacy of implantable cardioverter-defibrillators (ICD) to prevent sudden cardiac death was impaired by the substantial perioperative mortality of the therapy. With the introduction of transvenous-subcutaneous defibrillation leads, thoracotomy could be abandoned and perioperative mortality was reduced to less than 1%. Despite frequent lead complications as dislocations, conductor fractures and isolation failures, long-term efficacy in termination of ventricular tachyarrhythmias remained approximately 98% and prevention of sudden cardiac death was not impaired. All nonthoracotomy defibrillation lead systems involve an endocardial right ventricular lead usually introduced from the left cephalic vein or directly via the subclavian vein. This lead has a pace/sense tip and at least one defibrillation electrode located in the right ventricle. Additionally, a second transvenous electrode and/or a subcutaneous patch or array electrode or the pulse generator shell has to be used for defibrillation. In combination with the biphasic defibrillation waveform, virtually all patients can be defibrillated using a combination of these electrodes. In most patients defibrillation is possible with transvenous electrodes alone and there is no need for an additional subcutaneous electrode. Smaller pulse generators have already been implanted in a subpectoral position--in many patients allowing a single incision approach as used for pacemaker implantation. Ultimately, with even smaller pulse generators ICDs should be implantable like present pacemakers in local anesthesia. This overview covers the history, models, practical aspects of implantation and testing, efficacy and complications of transvenous/subcutaneous defibrillation leads. Figures show the impact of the surgical approach on the frequency of de novo ICD implantations, X-rays of nearly all current bipolar and tripolar transvenous subcutaneous ICD lead systems, transvenous-epicardial hybrid systems and various complications. Additional figures cover lead complications not visible on X-rays. Defibrillation thresholds are compared for various lead configurations. Sensing amplitudes and pacing thresholds are compared for bipolar and pseudobipolar sense/pace leads as well as for different cardiac diseases. Tables summarize the main characteristics of current transvenous and subcutaneous ICD leads and external devices for intraoperative testing of ICD leads as well as the complications of transvenous/subcutaneous leads in three multicenter studies.