ABSTRACT
Riata® and Riata ST® implantable cardioverter defibrillator (ICD) leads (St. Jude Medical, Sylmar, CA) show an increased incidence of insulation defects, particularly "inside-out" lead fracture where inner, separately insulated cables penetrate through the surrounding silicone of the lead body. The exact incidence of Riata® lead problems is not clear and seems to range between 2-4% per year in the first 5 years after implantation according to new registry data. We recommend beyond a detailed information the following care of patients with Riata® and Riata ST® leads: 1) Activation of automatic ICD alerts, 2) remote monitoring with automatic daily alerts whenever possible, 3) monthly ICD controls in patients at high risk (pacemaker dependency, history of ventricular tachyarrhythmias) and high or moderate lead-related risk (8F, 7F single coil), 3-monthly controls in moderate patient and lead-related risk, 3 to 6-monthly controls in low patient and lead-related risk (no bradycardia, no history of ventricular tachyarrhythmia). Every ICD control should include meticulous analysis of oversensing artifacts in stored electrograms (EGMs) of sustained and non-sustained ventricular tachyarrhythmias and registration of EGMs during provocation testing (pectoral muscle activity, arm movements). If electrical abnormalities are observed, reoperation with addition of a new ICD lead is recommended; lead extraction only if indicated according to current guidelines. Fluoroscopy should only be performed if electrical abnormalities are found by an experienced electrophysiologist and a high frame rate and resolution. Management of fluoroscopic abnormalities in the absence of electrical abnormalities is not clear. Therefore, routine fluoroscopy of patients with Riata® leads without electrical abnormalities is not recommended.
Subject(s)
Cardiology/standards , Defibrillators, Implantable/standards , Device Removal/methods , Device Removal/standards , Electrodes, Implanted , Equipment Failure , Practice Guidelines as Topic , Germany , HumansABSTRACT
BACKGROUND: Health days are an established forum for prevention and health promotion for different groups in the general population. Through the use of modular questionnaires "Global Risk Assessment" (GloRiA) on computers (handheld and desktop), the recording of patient data and presentation of the results can be optimized. Possible applications include identification of risk factors, early detection of patients at risk, epidemiology and health services research, promotion of patient adherence by visualizations (e.g. risk scores). Up to 12 different question modules are available (e.g. risk for the occurrence of cardiovascularevents by Framingham score, forfuture riskof diabetes mellitus using FindRisk score, smoking, COPD, pain, comorbidities). METHODS AND RESULTS: During 57 health days in 2010 and 2011, data were collected from 3451 persons (53% women, mean age 59.6 +/- 15.4 years) using GloRiA. The percentage of former smokers was 32.7%, while that of current smokers was 14.7%. The average 10-year risk based on the Framingham score (calculated with 1739 persons) in 53.7% of respondents was at <10%, in 37.0% at 10-20%, and in 9.3% at > 20%. In men risk was higher than in women. Smoking cessation would theoretically reduce the mean 10-year risk from 10.9 +/- 9.2% to 7.4 +/- 6.6%. In 50.5% of participants blood pressure measurement revealed elevated values, and in 10% or 2%, respectively, a moderately high or high 10-year riskof incident diabetes mellitus according to FindRisk. CONCLUSION: The use of GloRiA for the consolidation of health data under the framework of health days provides new and sustained possibilities in early detection of cardiovascular disease. The calculation and visualization of risks and the impact of treatment decisions, e.g. reduction of cardiovascular risk by smoking cessation, were communicated directly to the participants. The individual health report facilitates the diagnostic procedures bya physician.
Subject(s)
Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/prevention & control , Diagnosis, Computer-Assisted/methods , Early Diagnosis , Electronic Health Records , Health Promotion/methods , Internet , Mass Screening/methods , Risk Assessment/methods , Software , Adult , Aged , Body Mass Index , Comorbidity , Female , Germany , Humans , Male , Middle Aged , Risk-Taking , Smoking/adverse effects , Smoking/epidemiology , Surveys and QuestionnairesABSTRACT
BACKGROUND: Sustained, stable wide QRS-complex tachycardia (WCT) remains a diagnostic challenge, because the treatment of supra-ventricular tachycardia (SVT) with aberrant conduction differs considerably from that of a ventricular tachycardia (VT). A usual recommendation for treating a case of a stable WCT is to manage it as if it were VT, in accordance with the consideration of "first do no harm". The aim of this study was to determine whether Board-certified emergency-physicians are able to differentiate VT from SVT with aberrant conduction in a high percentage of cases (> 90%), thus to assure more precise prehospital treatment." METHODS: Eight electrocardiograms with WCT (four with electrophysiologically proven VT or SVT, respectively) were evaluated in a blinded fashion by 64 Board-certified emergency-physicians (23 female, 41 male, mean age: 37,8 + 5,1 years). Initially, the diagnosis had to be made without any further information. Afterwards the same electrocardiograms were presented again, providing important additional information. RESULTS: 55% of the study population were able to establish the correct diagnosis merely by evaluating the electrocardiogram. Providing the above mentioned additional information, the number of correct diagnoses increased to 61%. These results were roughly similar in all subgroups, only the subgroup of cardiologists showed a trend to better results with correct diagnoses in 68% without and 73 % with additional information. None of the subgroups reached the pre-specified cut-off of > or = 90% correct diagnoses. Specialist status as well as experience in emergency medicine had no significant influence on the results, only the subgroup of emergency physicians with an experience of more than five years showed a trend towards a higher rate of correct diagnosis, compared with the subgroup with less than one year experience in emergency medicine. CONCLUSION: In cases of stable WCT the evaluation of the electrocardiogram without further information in prehospital emergency-medicine leads to unsatisfactory results. The correct diagnosis in WCT can be improved by using additional data but the diagnostic accuracy is still low. Therefore, the differential diagnosis of stable WCT in preclinical emergency-medicine cannot be recommended. Until proven otherwise, any stable WCT should be managed as if it were VT.
Subject(s)
Electrocardiography , Emergency Medical Services , Emergency Medicine , Tachycardia, Supraventricular/diagnosis , Tachycardia, Ventricular/diagnosis , Tachycardia/diagnosis , Adult , Diagnosis, Differential , Female , Humans , MaleABSTRACT
Age-related physiologic changes, a higher prevalence of chronic illness, and concomitant (often multiple) medication account for a higher susceptibility of elderly patients to syncope. Although elderly patients are the largest group with syncope, the causes frequently remain unclear. Multifactorial causes, lack of witnesses, overlap with falls, and additional cognitive impairment often confound the assessment of syncope in the elderly. Thus, strategic investigation is often needed to establish the diagnosis and to unmask the cause. In addition to a comprehensive medical history (by both patient and witnesses), a thorough physical examination including supine and standing blood pressure measurements and a standard 12 lead ECG remain the mainstay of diagnosis. The decision whether additional tests are needed depends on indications whether organic heart disease is present or not. Without evidence of structural heart disease, tilt table testing and studies of autonomic function are the next steps. In contrast, additional cardiac investigation (including invasive studies) is needed in patients with suspected or documented cardiac disease. External or implantable loop recorders represent a significant improvement in the diagnosis of rare episodes of (brady- or tachy)-arrhythmias. Prognosis is determined by the underlying (heart) disease.
Subject(s)
Heart Diseases/complications , Syncope/etiology , Aged , Aged, 80 and over , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/mortality , Cause of Death , Death, Sudden, Cardiac/prevention & control , Electrocardiography, Ambulatory/instrumentation , Electrodes, Implanted , Heart Diseases/diagnosis , Heart Diseases/mortality , Humans , Risk Factors , Syncope/mortalityABSTRACT
The study describes the electrophysiological effects of transvenous cardiac nerve stimulation in an animal model of myocardial infarction. In ten sheep with recent myocardial infarction, transvenous stimulation of parasympathetic cardiac nerves was achieved from a catheter in the right pulmonary artery. The effects of transvenous cardiac nerve stimulation on sinus rhythm cycle length, ventricular refractory periods and inducibility of monomorphic ventricular tachycardia were evaluated. Sinus rhythm cycle length increased from 620 +/- 24 ms to 723 +/- 30 ms during nerve stimulation with 20 Hz and to 779 +/- 28 ms during stimulation with 40 Hz (p < 0.05). Effective ventricular refractory periods from stimulation sites in non-infarcted right and left ventricular myocardium showed a tendency towards prolongation during cardiac nerve stimulation with shortening after cessation of stimulation. These differences, however, were not significant. In contrast, refractory periods from stimulation sites within the infarcted area remained unchanged during cardiac nerve stimulation. The inducibility of monomorphic ventricular tachycardia by programmed electrical stimulation was reduced during transvenous cardiac nerve stimulation. Pathological examination showed cholinergic nerves in close proximity to the tip of the stimulation catheter in the right pulmonary artery. Transvenous cardiac nerve stimulation in sheep with remote myocardial infarction exhibits electrophysiological effects on the ventricles. Although a parasympathetic effect on the ventricles could not be proven, the observed effects may result from direct stimulation of efferent parasympathetic nerves.
Subject(s)
Atrioventricular Node/physiopathology , Cardiac Pacing, Artificial/methods , Catheterization, Central Venous/methods , Myocardial Infarction/physiopathology , Myocardial Infarction/therapy , Parasympathetic Nervous System/physiopathology , Tachycardia, Ventricular/physiopathology , Animals , Cardiac Pacing, Artificial/adverse effects , Disease Models, Animal , Electric Stimulation Therapy , Myocardial Infarction/pathology , Sheep , Tachycardia, Ventricular/etiology , Tachycardia, Ventricular/pathology , Treatment OutcomeABSTRACT
The most effective and safest option for the prevention of atrial fibrillation and its sequelae--cardiovascular morbidity and mortality, stroke)--is primary prophylaxis. Here, the management of arterial hypertension--the most common cause underlying atrial fibrillation--is of considerable importance. In addition to blood pressure reduction, substances with an action of the autonomic nervous system and the renin-angiotensin-aldosterone system (ACE-inhibitors, AT1 antagonists, beta blockers) have a positive effect on the remodeling, so-called, of the atrial myocytes, and thus on the occurrence of atrial fibrillation with its associated stroke risk. For patients with elevated blood pressure, therefore, the therapeutic strategy should, in the individual case, give consideration to the possibility of exerting a positive effect on atrial fibrillation.
Subject(s)
Antihypertensive Agents/therapeutic use , Atrial Fibrillation/prevention & control , Hypertension/drug therapy , Adrenergic beta-Antagonists/therapeutic use , Angiotensin II Type 1 Receptor Blockers , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Atrial Fibrillation/epidemiology , Atrial Fibrillation/etiology , Coumarins/therapeutic use , Cross-Sectional Studies , Germany , Humans , Hypertension/complications , Hypertension/epidemiology , Intracranial Embolism/epidemiology , Intracranial Embolism/etiology , Intracranial Embolism/prevention & control , Risk Factors , Ventricular Remodeling/drug effectsABSTRACT
AIMS: Efficacy of pace-termination of atrial arrhythmias (ATP) may depend on atrial cycle length and regularity. Whether device programming of ATP therapies can improve ATP efficacy and alter atrial tachyarrhythmia burden is unknown. METHODS AND RESULTS: ATP efficacy was evaluated in 61 patients (39 males; 66 +/- 10 years) with a standard indication for pacing, 95% with a history of AT/AF. Each patient was implanted with a novel DDDRP pacemaker capable of delivering ATP therapy. ATP efficacy and AT/AF frequency and burden were compared within each patient during a period of nominal ATP programming (NP) followed by a period of aggressive incremental programming (IP). Adjusted ATP-termination efficacy was higher during IP than during NP (54.8% vs 37.9%, P < 0.05). No differences in AT/AF frequency (3.3 +/- 5.9 vs 3.2 +/- 6.9 day(-1)) or burden (18 +/- 28% vs 18 +/- 29%) were observed comparing NP with IP. The majority of episodes during both the NP (81%) and IP (77%) periods terminated within 10 min. Episodes lasting 24 h or more accounted for only 0.4% of the episodes in both groups. but accounted for 38% of the average burden during NP and 51% during IP. CONCLUSIONS: Device programming of ATP therapies can influence the number of treated episodes and the efficacy of ATP therapies although arrhythmic frequency and burden may not change. Total atrial arrhythmia burden is disproportionately influenced by long (>24 h) episodes.
Subject(s)
Atrial Fibrillation/therapy , Atrial Flutter/therapy , Pacemaker, Artificial , Tachycardia/therapy , Aged , Cardiac Pacing, Artificial/methods , Female , Humans , Male , Prospective Studies , Time FactorsABSTRACT
The Wearable Cardioverter Defibrillator (WCD) is an external defibrillator that automatically detects and treats ventricular tachyarrhythmias without the need for assistance from a bystander while at the same time allowing the patient to ambulate freely. The main components of the system are the defibrillator unit and a chest belt with electrodes for arrhythmia detection and therapy delivery. Between December 1998 and October 2001, 84 patients used the device at our institution. The majority of patients had a history of acute myocardial infarction or coronary artery bypass surgery with an increased risk for sudden cardiac death or were awaiting heart transplantation. During a mean follow-up of 116+/-90 days, 7 episodes of ventricular tachyarrhythmias were detected and terminated successfully by the WCD in 5 patients. In 9720 days, there was one inappropriate shock due to oversensing of electrical noise. Four patients died during follow-up; none of them had a cardiac arrest while wearing the device. Five patients were excluded because of irregularities in device use. An ICD was implanted in 24 patients at the end of the follow-up period. The WCD is effective in detecting and treating ventricular tachyarrhythmias in patients with an intermittently increased risk for sudden cardiac death. Further use of the system in larger patient populations is needed to confirm its safety and cost effectiveness.
Subject(s)
Death, Sudden, Cardiac/prevention & control , Defibrillators, Implantable , Electric Countershock , Aged , Coronary Artery Bypass , Electric Countershock/instrumentation , Female , Follow-Up Studies , Heart Transplantation , Humans , Male , Middle Aged , Myocardial Infarction , Risk Factors , Tachycardia, Ventricular/therapy , Time Factors , Ventricular Fibrillation/therapySubject(s)
Catheter Ablation , Ventricular Premature Complexes/therapy , Adrenergic beta-Antagonists/therapeutic use , Anti-Arrhythmia Agents/therapeutic use , Clinical Trials as Topic , Electrocardiography , Follow-Up Studies , Humans , Patient Selection , Treatment Outcome , Ventricular Premature Complexes/diagnosis , Ventricular Premature Complexes/drug therapyABSTRACT
The limited efficacy of and side effects associated with antiarrhythmic drug therapy have led to renewed interest in non-pharmacologic treatment options for paroxysmal atrial fibrillation. In addition to catheter ablation of the initiating ectopic atrial beats, electrical stimulation of the atrium is a new and promising method to reduce the frequency of arrhythmia recurrences. Recent studies have confirmed the importance of both the initiating triggers and the electrophysiologic substrate for the recurrence and perpetuation, respectively, of atrial fibrillation. Bradycardia and pauses, atrial premature beats, and early recurrence of atrial fibrillation all seem to play an important role for (re-)initiation of an episode. Results from single-site atrial pacing in the high right atrium have shown a reduction of atrial fibrillation episodes and progression into chronic atrial fibrillation in selected groups of patients (brady-tachycardia syndrome and vagally induced atrial fibrillation). Therefore, specific preventive pacing algorithms (atrial overdrive pacing, rate smoothing or rate acceleration after detection of atrial premature beats and termination of a mode-switch) and new pacing sites have recently been investigated in order to address all of these initiation mechanisms and to increase the efficacy of pacing. In studies published so far, the specific pacing algorithms seem to add benefit compared to atrial-based demand (AAI or DDD) pacing alone. Finally, attempts are being made to terminate recurrences of atrial tachycardia or atrial flutter with antitachycardia pacing algorithms in order to avoid progression into atrial fibrillation. Based on experimental and clinical evidence, the initial phase of the majority of atrial tachyarrhythmia recurrences is not 'leading circle reentry'. Most episodes start relatively regular and seem to have an excitable gap, allowing capture and pace termination.
Subject(s)
Aldosterone/blood , Atrial Fibrillation/therapy , Electric Countershock , Atrial Fibrillation/blood , Chronic Disease , Female , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
Although radiofrequency (RF) catheter ablation has been shown to be an effective treatment strategy in patients with supraventricular tachycardia, RF ablation may lead to potentially serious complications. We describe a case of a 65-year old man who was transferred for catheter ablation of typical atrial flutter. 21 RF applications (mean energy: 81+/-9 watts) were applied in the temperature-controlled mode (70 degrees C) between a 8-mm tip electrode and an indifferent electrode using a high-power RF generator (100 watts) until bi-directional atrial isthmus block was achieved. After the procedure, a third-degree skin burn (10x2 cm) was observed at the lateral edge of the adhesive indifferent electrode whereas the medial edge of the electrode was not fully attached to the skin surface. This case is one out of 1128 ablation procedures (0.09 %) at our institution using a high-power RF generator. The present study demonstrates a severe skin burn induced by mal-attachment of an indifferent electrode during RF ablation. Long RF energy application times, high-power settings, and heavy sedation may have contributed to the observed severity of skin damage.
Subject(s)
Atrial Flutter/surgery , Burns, Electric/etiology , Catheter Ablation/adverse effects , Catheter Ablation/instrumentation , Aged , Atrial Flutter/diagnosis , Burns, Electric/diagnosis , Burns, Electric/surgery , Electrodes/adverse effects , Follow-Up Studies , Humans , Injury Severity Score , Male , Risk Assessment , Skin Transplantation/methods , Treatment OutcomeSubject(s)
Death, Sudden, Cardiac/prevention & control , Anti-Arrhythmia Agents/therapeutic use , Arrhythmias, Cardiac/complications , Clinical Trials as Topic , Defibrillators, Implantable , Electrocardiography , Follow-Up Studies , Heart Diseases/complications , Humans , Myocardial Infarction/complications , Primary Prevention , Prospective Studies , Risk Factors , Time Factors , Ventricular Dysfunction, Left/complicationsABSTRACT
Maintenance of sinus rhythm is the primary goal of antiarrhythmic drug therapy for recurrent atrial fibrillation (AF). However, concern about proarrhythmic and negative inotropic effects has led to increasing reluctance to administer antiarrhythmic agents for this non-life-threatening arrhythmia. Moricizine is well tolerated in a wide variety of patients, and therefore, may be a safe and effective agent for treating AF. We retrospectively assessed the efficacy and safety of moricizine (mean dose 609 +/- 9 mg/day) in 85 consecutive patients with recurrent AF (2.6 +/- 0.5 years duration, 1.6 +/- 1 failed antiarrhythmic drugs). Structural heart disease was present in 69 (81%), but no recent myocardial infarct (< or =90 days) was present; mean left atrial size was 46 +/- 1 mm, and mean left ventricular ejection fraction was 0.51 +/- 0.01. Moricizine was discontinued because of unsuccessful direct-current cardioversion (n = 5) or clinically unacceptable side effects (n = 6); 6 patients developed transient side effects not requiring discontinuation. Of the 74 patients continuing therapy, 68% remained in sinus rhythm after 6 months, and 59% after 12 months. During a follow-up (21 +/- 2 months), there were neither deaths nor adverse effects requiring discontinuation of therapy. Thus, moricizine was effective, safe, and well tolerated in our patient cohort with AF.
Subject(s)
Anti-Arrhythmia Agents/therapeutic use , Atrial Fibrillation/drug therapy , Moricizine/therapeutic use , Adult , Aged , Aged, 80 and over , Atrial Fibrillation/physiopathology , Electrocardiography , Female , Heart Rate , Humans , Male , Middle Aged , Recurrence , Retrospective StudiesABSTRACT
BACKGROUND: Previous studies have suggested that atrial fibrillation (AF) is associated with the activation of the atrial angiotensin system. However, it is not known whether the expression of angiotensin II receptors changes during AF. The purpose of this study was to determine the atrial expression of angiotensin II type 1 and type 2 receptors (AT(1)-R and AT(2)-R) in patients with AF. METHODS AND RESULTS: Atrial tissue samples from 30 patients undergoing open heart surgery were examined. Eleven patients had chronic persistent AF (> or =6 months; cAF), 8 patients had paroxysmal AF (pAF), and 11 patients were in sinus rhythm. AT(1)-R and AT(2)-R were localized in the atrial tissue by immunohistochemistry and quantified at the protein and mRNA level by Western blotting and quantitative polymerase chain reaction. Both types of AT-R were predominantly expressed in atrial myocytes in all groups. The amount of AT(1)-R was reduced to 34.9% during cAF (P<0.01) and to 51.7% during pAF (P<0.05) compared with patients in sinus rhythm. In contrast, AT(2)-R was increased during cAF (246%; P=NS) and pAF (505%; P<0.01). AT(1)-R/AT(2)-R mRNA content was similar in all groups. CONCLUSIONS: AF is associated with the down-regulation of atrial AT(1)-R and the up-regulation of AT(2)-R proteins. These findings may help define the pathophysiological role of the angiotensin system in the structural remodeling of the fibrillating atria.
Subject(s)
Atrial Fibrillation/metabolism , Myocardium/metabolism , Receptors, Angiotensin/genetics , Receptors, Angiotensin/metabolism , Adult , Aged , Atrial Fibrillation/physiopathology , Blotting, Western , Female , Gene Expression/physiology , Humans , Immunohistochemistry , Male , Middle Aged , Myocardium/chemistry , RNA, Messenger/analysis , Receptor, Angiotensin, Type 1 , Receptor, Angiotensin, Type 2 , Receptors, Angiotensin/analysisABSTRACT
OBJECTIVES: The purpose of this study was to determine whether atrial expression of the extracellular signal-regulated kinases Erk1/Erk2 and of the angiotensin-converting enzyme (ACE) is altered in patients with atrial fibrillation (AF). BACKGROUND: Recent studies have demonstrated that atrial fibrosis can provide a pathophysiologic substrate for AF. However, the molecular mechanisms responsible for the development of atrial fibrosis are unclear. METHODS: Atrial tissue samples of 43 patients undergoing open heart surgery were examined. Seventeen patients had chronic persistent AF (> or =6 months; CAF), 8 patients had paroxysmal AF (PAF) and 18 patients had no history of AF. Erk expression was analyzed at the mRNA (quantitative reverse transcription polymerase chain reaction), the protein (immunoblot techniques) and atrial tissue (immunohistochemistry) levels. Erk-activating kinases (MEK1/2) and ACE were analyzed by immunoblot techniques. RESULTS: Increased amounts of Erk2-mRNA were found in patients with CAF (75 +/- 20 U vs. sinus rhythm: 31 +/- 25 U; p < 0.05). Activated Erk1/Erk2 and MEK1/2 were increased to more than 150% in patients with AF compared to patients with sinus rhythm. No differences between CAF and PAF were found. The expression of ACE was three-fold increased during CAF. Amounts of activated Erk1/Erk2 were reduced in patients treated with ACE inhibitors. Patients with AF showed an increased expression of Erk1/Erk2 in interstitial cells and marked atrial fibrosis. CONCLUSIONS: An ACE-dependent increase in the amounts of activated Erk1/Erk2 in atrial interstitial cells may contribute as a molecular mechanism for the development of atrial fibrosis in patients with AF. These findings may have important impact on the treatment of AF.
