[Scientific results of the pacemaker register: possibilities and limits]. / Wissenschaftliche Ergebnisse des Herzschrittmacherregisters: Möglichkeiten und Grenzen.

The German obligatory external quality assurance for pacemaker implantation generates a large database giving an almost complete review of in-patient pacemaker interventions since 2001. Publications on lead fixation, age and gender dependency of pacemaker indications, choice of pacing mode and complication rates as well as investigations into the causes of lead dysfunction prove that the database is basically suitable for health service research. In contrast to pacemaker registries of other European countries the focus on in-patient operations, missing product specifications and the absence of patient follow-up largely limits the scientific potential of the database. It is greatly hoped that these limitations will be overcome by cross-sectional and longitudinal quality assurance within the next years.

[Training requirements for transvenous implantation of pacemakers and cardioverter-defibrillators]. / Empfehlungen zur strukturierung der herzschrittmacher- und defibrillatortherapie.

Therapy with implantable pacemakers, cardioverter defibrillators (ICD), and devices for cardiac resynchronization (CRT) is performed by various medical and surgical specialists. With the change from implantation by thoracotomy to the transvenous approach, an increasing number of devices are implanted by cardiologists. The purpose of this paper is to establish training requirements for transvenous device therapy, implantation and follow-up examinations, regardless of the implanting person, an internist, cardiologist, general surgeon, or cardiothoracic surgeon. Epicardial lead placement should be performed only by surgeons. Two levels of training topics are defined, level 1 for pacemakers and level 2 for ICD and CRT devices. Surgery that involves the implantation of foreign material should demand the highest standards of operating rooms design and environment. Catheter laboratories used for implantations should meet operating room standards. Complications need to be documented carefully for quality control.

[Avoidance of ventricular pacing in patients with sinus node disease or intermittent AV block]. / Ventrikuläre Stimulationsvermeidung bei Patienten mit Sinusknotenerkrankung oder intermittierendem AV-Block.

In patients with frequent right ventricular stimulation, worsening of heart failure and atrial fibrillation may occur. Avoidance of unnecessary right ventricular pacing is a major requirement for pacemaker selection and programming in patients with sinus node disease or intermittent AV block. In dual chamber pacemakers this goal can be achieved by programming a long AV delay or an AV delay hysteresis. Algorithms that allow AAI pacing in a dual chamber pacing mode and change to DDD mode in case of high degree AV block are a new attempt to avoid unnecessary right ventricular pacing. The article describes various strategies to avoid unnecessary ventricular pacing and discusses their advantages and disadvantages.

Influence of anxiety on the course of heart disease after acute myocardial infarction - risk factor or protective function?

BACKGROUND: There is a lack of clarity concerning the effect of anxiety on the course of cardiac events following myocardial infarction. Some studies have identified anxiety as a risk factor for further cardiac events. However, it is also considered to be a protective factor, as a higher level of anxiety may improve patient compliance and regular medical checkups. METHODS: A group of 76 patients with myocardial infarction underwent physical examination and had their anxiety levels assessed within the first week, and 31 months after myocardial infarction. Cardiac events were documented during the follow-up period. We investigated the predictive value for the occurrence of cardiac events of sociodemographic, psychological and physical parameters when evaluated within the first week after myocardial infarction. Compliancy and regularity of medical checkups were registered. RESULTS: Cardiac events occurred in 24 patients during a mean follow-up period of 31 months. The group of anxious patients not only suffered more often from cardiac events, these events also occurred earlier than in nonanxious patients. Age, gender, partner status, level of anxiety and comorbid diabetes at the time of first assessment proved to be discriminatory variables between patients suffering further cardiac incidents and those free of further events. Anxious patients were more likely to continue smoking, whereas less anxious patients were more likely to give up smoking.

Long term complications in single and dual chamber pacing are influenced by surgical experience and patient morbidity.

OBJECTIVE: To determine how short and long term complication rates after pacemaker implantation are influenced by patient morbidity, operator experience, and choice of pacing system. DESIGN: Retrospective analysis of 1884 patients who received VVI (n = 610), VDD (n = 371), or DDD devices (n = 903) between 1990 and 2001. Follow up period was 64 (34) months. The influence of age, sex, coronary artery disease, myocardial infarction, reduced left ventricular (LV) function, right ventricular (RV) dilatation, atrial fibrillation, device type, and operator experience on operation time and complication rate were analysed. RESULTS: Operation time was prolonged in patients with coronary artery disease, inferior myocardial infarction, reduced LV function, and RV dilatation. Implantation of DDD pacemakers prolonged operation time, particularly among operators with a low or medium level of experience. The overall complication rate was 4.5%. Sixty seven per cent of these complications occurred within the first three months. Complication rate was increased by age, reduced LV function, and RV dilatation. Implantation of DDD systems led to a higher complication rate (6.3%) than implantation of VVI (2.6%) or VDD pacemakers (3.2%). These differences were present only among operators with a low or medium level of experience. CONCLUSIONS: Operation time and complication rate increased with age, impaired LV function, and RV dilatation. Complication rates were higher with DDD than with VVI or VDD implantation and were excessive among inexperienced but not experienced operators.

Red, yellow, green go!--A novel tool for microscopic segregation of secretory vesicle pools according to their age.

Large dense-core vesicles (LDCVs) were labelled in cultured bovine adrenal chromaffin cells expressing fluorescent chimaeric 'cargo' proteins that were targeted to these secretory vesicles. When the cells were stimulated with nicotine 48 h after transduction, the fractional loss of fluorescent LDCVs was much greater than the fractional catecholamine secretion, implying selective release of newly assembled vesicles. This was confirmed using a fluorescent 'timer' construct that changes its fluorescence emission from green to red over several hours, and by measurement of the location and mobility of LDCVs in live cells by confocal fluorescence microscopy. Newly assembled (green) LDCVs were located mostly in peripheral regions of the cells, were virtually immobile and could be released by nicotine, but not by Ba2+; in contrast, older (red) LDCVs were centrally located and relatively mobile, and their exocytotic release was triggered by Ba2+, but not by nicotine. We describe the image restoration procedure that is necessary in order to analyse the behaviour of LDCVs labelled with this construct.

Plasma catecholamines and N-terminal proBNP in patients with acute myocardial infarction undergoing primary angioplasty. Relation to left ventricular function and clinical outcome.

BACKGROUND: Neither profiles nor prognostic values of neurohormonal markers have been prospectively evaluated in patients with acute myocardial infarction (AMI) undergoing primary angioplasty. METHODS AND RESULTS: In 118 consecutive patients with AMI undergoing successful reperfusion (TIMI 2 and 3) by primary angioplasty, plasma concentrations of norepinephrine, epinephrine and N-terminal proBNP (NT-proBNP) were measured before, 60 min and 10 days after angioplasty. Catecholamine concentrations (mean+/-SEM) rose to a maximum in the first hour after angioplasty (norepinephrine: 602+/-44 ng/L, epinephrine: 213+/-24 ng/L) and returned to normal at day 10. Conversely, NT-proBNP levels maintained a further increase from 799+/-44 pmol/L at baseline to 924+/-54 pmol/L at day 10. A NT-proBNP concentration above median at 60 min post-angioplasty predicted major adverse cardiac events (n=27) during the 18-36 month follow-up with an odds ratio of 5.9 (1.7-20.3) and was superior to catecholamines, to left ventricular ejection fraction and to other established postinfarction risk markers. CONCLUSIONS: In a low-risk cohort of patients with AMI undergoing successful reperfusion therapy, plasma NT-proBNP concentrations are elevated for at least ten days. The prognostic value of early plasma NT-proBNP should be further evaluated concerning its ability to facilitate risk stratification of infarct patients.

[Preventive pacemaker stimulation in atrial fibrillation]. / Präventive Schrittmacherstimulation bei Vorhofflimmern.

Preventive pacing algorithms and the use of alternative or multifocal pacing sides are new approaches for treatment of paroxysmal atrial tachyarrhythmias. However, present data are not sufficient to define a new indication for pacemaker implantation in patients with refractory atrial fibrillation. Yet, preventive pacing should be predominantly performed either in patients with an established pacemaker indication or during controlled study projects. In patients undergoing cardiac surgery, biatrial overdrive pacing using temporary epicardial wires can be recommended for prevention of postoperative atrial fibrillation.

Meningioma gigante en edad pediátrica: caso clínico y revisión de la literatura / Giant meningioma in pediatric age: clinical case and literature review

Se presenta el caso clínico de una menor de menos de tres años portadora de un meningioma gigante que invadía la región temporal, fose pterigomaxilar y órbita a izquierda. Se describe el manejo clínico quirúrgico y la evolución muy favorable del caso. Se revisa la literatura y se discute la poca frecuencia de este tipo de tumores en la edad pediátrica.

Over-expression of NCS-1 in AtT-20 cells affects ACTH secretion and storage.

The effect of over-expressing neuronal calcium sensor 1 (NCS-1) upon stimulated adrenocorticotrophin (ACTH) secretion was studied in AtT-20 cells. Stably-transfected AtT-20 cell lines over-expressing NCS-1 were obtained and compared to wild type AtT-20 cells. Corticotrophin releasing factor (CRF-41)-stimulated ACTH secretion from NCS-1 over-expressing cells was significantly reduced from that obtained in wild type AtT-20 cells. The effects of other stimulants of ACTH secretion from wild type AtT-20 cells were not attenuated in NCS-1 over-expressing cells. Calcium, guanosine 5'-O-(3'-thiotriphosphate) (GTP-gamma-S) and mastoparan stimulated ACTH secretion from permeabilised wild type AtT-20 and NCS-1 over-expressing AtT-20 cells with significantly greater ACTH secretion obtained in NCS-1 over-expressing cells. This study shows that in intact cells over-expression of NCS-1 reduces exocytotic ACTH release, while in permeabilised cells increases ACTH release. NCS-1 has multiple cellular targets and that directly and indirectly via these targets acts to increase the releasable ACTH pool while inhibiting CRF-41 stimulus-secretion coupling.

Incidence and predictors of pacemaker dysfunction with unipolar ventricular lead configuration. Can we identify patients who benefit from bipolar electrodes?

Unipolar ventricular leads were implanted in a considerable percentage of pacemaker recipients. There is little information on incidence and risk factors for unipolar pacemaker dysfunction using modern lead designs. Included in a cross-sectional analysis were 682 patients who fulfilled the following criteria: chronically implanted bipolar ventricular leads (> 1 year), intraoperative stimulation threshold < 1.0 V/0.5 ms, and potential amplitude > 6 mV. Incidences of chest wall stimulation (CWS) at an output of twice the amplitude threshold and of myopotential oversensing (MPO) at a sensitivity of half the sensing threshold were assessed. Energy (0.60 [0.72] vs 0.63 [0.81] microJ) and sensing thresholds (8.31 [3.18] mV vs 8.47 [3.47] mV) did not differ between uni- and bipolar modes. While all pacemakers worked properly during bipolar configuration, malfunctions were observed in 5.9% of patients during unipolar configuration (CWS = 1.9%, MPO = 4.2%). Patient age > 76 years (hazard ratio HR 8.2; P < 0.001), heart failure > or = NYHA Class II (HR 3.8; P < 0.001), and an antiarrhythmic therapy with Class I or III drugs (HR 3.3; P = 0.002) were independently associated with the occurrence of unipolar pacemaker dysfunction. Use of steroid-eluting leads reduced the probability of pacemaker dysfunction (HR 0.45; P = 0.03). Risk factors for unipolar ventricular pacemaker malfunction were higher age, heart failure, and antiarrhythmic drug therapy. Particularly in these patients, use of bipolar ventricular leads is beneficial.

Troponin T elevation after successful directional atherectomy.

BACKGROUND: The incidence and correlates of postinterventional cardiac troponin T (cTnT) elevation have not been evaluated in patients with successful directional atherectomy (DCA). METHODS: Total creatine kinase (CK) activity, CK-MB mass concentrations and cTnT levels were measured in 36 patients before, and serially 4, 24, 48 and 72 hours after successful DCA. Patients were followed for death, Q-wave infarction, need for emergency bypass surgery, periprocedural vascular complications (transient in-lab vessel closure, side branch compromise, large dissection), and non-Q-wave infarction on ECG. Patients were followed for clinical outcomes and angiographic restenosis for 6 months. Vascular correlates were studied by coronary angiography and intravascular ultrasound before, immediately after and 4 hours after elective and successful DCA. RESULTS: 25 patients (69.4%) had elevated levels of cTnT, whereas CK-MB mass > or = 6 ng/ml and mild elevations of total CK activity were present in only 36.1 and 5.6%, respectively. Elevated cTnT was related to vascular complications in 44% of cases. Inapparent microembolization of platelets or plaque debris was considered responsible for most of the remaining micronecroses. During 6 month follow-up rates of clinical restenosis (44 vs 9%, p = 0.059) tended to be higher in patients with as compared to patients without cTnT release after DCA. CONCLUSION: Successful DCA is associated with postprocedural elevations of cTnT which relate to minor vascular complications and presumably microembolization of platelets or plaque debris. The superior diagnostic performance of cTnT compared to CK-MB mass may relate to more sensitive identification of microinfarction. Further studies are mandatory to confirm the association between elevation of cTnT and risk of restenosis and TVR.

Delayed restoration of atrioventricular synchrony with beat-to-beat mode switch.

This case report describes a patient with complete AV block and a VDD pacemaker who experienced repetitive episodes of symptomatic bradycardia. Episodes occurred due to activation of an automatic beat-to-beat mode switch algorithm. After mode switch to VDI operation, the pacemaker failed to immediately switch back to AV synchronous pacing when regular sinus rhythm (> or = 100 beats per minute) resumed despite adequate P wave sensing. Dizziness was felt for up to several minutes of asynchronous pacing at the lower rate limit until VDD mode was restored. Episodes were completely eliminated by programming the mode switch function from an automatic beat-to-beat algorithm to a fixed rate algorithm.