Prevalence and clinical relevance of the morphological substrate of ventricular arrhythmias in patients without known cardiac conditions detected by cardiovascular MR.

OBJECTIVE: Cardiac MR (CMR) identifies the substrate of ventricular arrhythmia (VA) in cardiomyopathies and coronary heart disease. However, little is known about the value of CMR in patients with VA without previously known cardiac disorders. METHODS: 76 patients with VA (Lown ≥2) without known cardiac disease after regular diagnostic work-up were studied with CMR, and findings were correlated with electrocardiogram (ECG) and electrophysiological stimulation (EPS). Structural abnormalities matching the VA origin as defined by ECG and/or EPS, or a CMR-detected cardiac condition known to cause arrhythmia were defined as VA substrate. CMR findings were defined as clinically relevant, if resulting in a new diagnosis, change of treatment or additional diagnostic procedure. RESULTS: 44/76 patients demonstrated pathological CMR findings. In 24/76 patients, the pathology was detected by CMR and not by echocardiography. CMR-based diagnoses of cardiac disease were established in 20/76 patients, and all were morphological substrates for VA. In seven patients, the location of the CMR finding (scar) directly matched the VA origin. CMR findings resulted in a change of treatment in 21 patients and/or additional diagnostics in 8 patients. CONCLUSION: Undetected cardiac conditions are frequent causes of VA. This is the first study demonstrating the value of CMR for detection of morphological substrate and/or underlying cardiac disorders in VA patients without known cardiac disease. ADVANCES IN KNOWLEDGE: The high incidence of clinically relevant CMR findings which were not detected during initial diagnostic work-up strongly supports the use of CMR to screen VA patients for underlying heart disease.

Outcome of atrial fibrillation ablation: assessment of success.

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia with a prevalence in the general population of approximately 1%. Catheter ablation has emerged from being a highly experimental procedure to one of the most common ablation performed in many electrophysiology laboratories throughout the world. The stability of sinus rhythm restored by catheter ablation is important not only for comparison of different ablation techniques, but also for guiding anticoagulation and possible antiarrhythmic drug treatment. It has been shown that asymptomatic AF after ablation is at least as common as before the ablation. Rhythm assessment is therefore a key component of post AF ablation follow-up. A variety of electrocardiogram (ECG) monitoring techniques is available. Besides of technical characteristics such as the number of recording leads and further signal processing, these techniques differ mainly in the duration of ECG recordings and the involvement of the patient. Intermittent rhythm monitoring techniques include standard 12-lead ECG, Holter-ECG of various duration, patient activated external loop ECG recorder as well as patient activated transtelephonic ECG monitor. Continuous ECG represents the gold standard for rhythm monitoring recording and can be achieved by means of a pacemaker, implan-table defibrillator or implantable cardiac ECG monitor.

Modern noninvasive risk stratification in primary prevention of sudden cardiac death.

OBJECTIVE: Since the publication of MADIT II and SCD-HeFT, an implantable cardioverter defibrillator (ICD) for primary prevention represents an established, guideline-implemented therapeutic strategy. Facing such an enormous amount of potential ICD recipients, the identification of an effective risk stratification remains crucial. METHODS: This article reviews the tools of noninvasive risk stratification which are currently used and defines an optimal test configuration. This analysis focuses on the capacity of the tests regarding to the negative predictive value to reduce unneeded devices. RESULTS: Presently, no marker exists in terms of risk stratification which qualifies itself as gold standard. However, encouraging results can be stated for microvolt T-wave alternans (mTWA) providing a high negative predictive value. An increased QT variability (QTv) and an impaired deceleration capacity are associated with an excellent positive predictive value. Currently, only mTWA and QTv seem to be suitable in ischemic and non-ischemic disease, but available data, especially in non-ischemic patients, are too small to provide clear recommendations. CONCLUSION: The most hopeful tools at hand in modern noninvasive risk evaluation of sudden cardiac death in primary prevention seem to be mTWA and QTv. These noninvasive methods provide the best negative predictive or positive predictive value of all known parameters, while a higher rate of complete coronary revascularizations in acute coronary syndromes might also reduce the number of fatal arrhythmic events and therefore complicate the invention of an ideal risk marker.

Cardiac asystole in epilepsy: clinical and neurophysiologic features.

PURPOSE: Cardiac asystole provoked by epileptic seizures is a rare but important complication in epilepsy and is supposed to be relevant to the pathogenesis of sudden unexplained death in epilepsy (SUDEP). We sought to determine the frequency of this complication in a population of patients with medically intractable epilepsy and to analyze the correlation between EEG, electrocardiogram (ECG), and clinical features obtained from long-term video-EEG monitoring. METHODS: Retrospective analysis of the clinical records of hospitalized patients from May 1992 to June 2001 who underwent long-term video-/EEG monitoring. RESULTS: Of a total of 1,244 patients, five patients had cardiac asystole in the course of ictal events. In these patients, 11 asystolic events, between 4 and 60 s long in a total of 19 seizures, were registered. All seizures had a focal origin with simple partial seizures (n = 13), complex partial seizures (n = 4), and secondarily generalized seizures (n = 2). One patient showed the longest asystole ever reported (60 s) because of a seizure. Cardiac asystole occurred in two patients with left-sided temporal lobe epilepsy (TLE) and in three patients with frontal lobe epilepsy (FLE; two left-sided, one bifrontal). Two patients reported previous cardiac disease, but only one had a pathologic ECG by the time of admission. Two patients had a simultaneous central ictal apnea during the asystole. None of the patients had ongoing deficits due to the asystole. CONCLUSIONS: These findings confirm that seizure-induced asystole is a rare complication. The event appeared only in focal epilepsies (frontal and temporal) with a lateralization to the left side. A newly diagnosed or known cardiac disorder could be a risk factor for ictal asystole. Abnormally long postictal periods with altered consciousness might point to reduced cerebral perfusion during the event because of ictal asystole. Central ictal apnea could be a frequent associated phenomenon.

Catheter ablation for cardiac arrhythmias.

The clinical introduction of catheter ablation in 1981 revolutionized the treatment of cardiac arrhythmias. Implementation of radiofrequency as an alternative energy source, with the advantages of higher selectivity and less collateral damage, provided an expansion of catheter ablation therapy. Today the majority of arrhythmias can potentially be cured with catheter ablation therapy. The safety and efficacy of catheter ablation for treatment of AV nodal reentrant tachycardia, accessory pathway arrhythmias, focal atrial tachycardia, atrial flutter and idiopathic ventricular tachycardia, is well established. Catheter ablation for treatment of atrial fibrillation and ventricular tachycardia secondary to structural heart disease, remains an area of active research. In this article we will review the current state of knowledge about the technique, indications, and results of catheter ablation for the treatment of cardiac arrhythmias.

Segmental hepatic vein thrombosis associated with heparin-induced thrombocytopenia II.

We report the case of a 55-year-old man who developed heparin-induced thrombocytopenia II after a vertebral fracture. Autopsy revealed segmental hepatic vein thrombosis of the right lobe with subacute congestion and an activation of hepatic stellate cells. This case shows that heparin-induced thrombocytopenia II is a possible cause of the Budd-Chiari syndrome.

[Penetrating atherosclerotic ulcer of the thoracic aorta descendens]

Penetrating atherosclerotic ulcer of the thoracic aorta descendens. HISTORY AND CLINICAL FINDINGS: A 75-year-old man with a history of generalised atherosclerosis was admitted to hospital for invasive assessment of progredient typical angina pectoris. Apart from diminished peripheral pulses, physical examination was normal. INVESTIGATIONS: Coronary angiography revealed a three vessel coronary artery disease. The chest X-ray showed elongation and dilatation of the distal aortic arch and the proximal descending aorta thoracalis. Computed tomography and magnetic resonance imaging of the thorax as well as magnetic resonance angiography of the thoracic aorta, demonstrated a penetrating atherosclerotic ulcer of the descending aorta thoracalis, with extensive intramural hematoma. TREATMENT AND COURSE: After percutaneous ballon-dilatation of the right coronary artery and the circumflex artery, the patient was asymptomatic. Considering all aspects of the patients condition, medical treatment of the penetrating atherosclerotic ulcer was decided for the patient. The findings of the thoracic computed tomography after 6 months were unchanged. CONCLUSION: The penetrating atherosclerotic ulcer of the thoracic aorta is a less known clinical entity. Our case report demonstrates that even extensive forms can be clinical asymptomatic and discovered by routine radiologic examinations.

Percutaneous extraction of an abandoned coiled pacing lead.

Abandoning redundant pacing leads has been an accepted practice in most cases. Late migration of a lead is a rare, unpredictable, and potentially lethal complication of this approach and requires immediate removal. We report the case of an atrial pacing lead that had migrated and was found coiled in the right atrium. It was removed by a snare catheter via a femoral approach.

Inappropriate implantable defibrillator discharge caused by a retained pacemaker lead fragment.

INTRODUCTION: Inappropriate discharge is still a major issue of implantable cardioverter defibrillator therapy. The diagnostic options of modern devices facilitate classification of the underlying abnormality. METHODS AND RESULTS: A 65-year-old woman with depressed left ventricular performance received spurious shocks from an ICD, implanted for ventricular tachycardia. A lead fragment of an explanted VVI pacemaker system could be identified as cause of erroneous ventricular fibrillation detection by the ICD. The electrical noise caused by interaction between the lead remnant and the ICD lead was detectable even on the surface ECG. CONCLUSION: Based on our findings, removal of fragmented lead material should be considered prior to ICD implantation, to avoid potentially adverse and harmful interactions with ICD systems.

[Acute posterior wall infarct after factor VIII concentrate administration to a patient with severe hemophilia A]. / Akuter Hinterwandinfarkt nach Faktor-VIII-Konzentrat bei schwerer Hämophilie A.

HISTORY AND CLINICAL FINDING: A 69-year-old man with severe haemophilia A sustained an acute myocardial infarction (MI) after self-administration of 3000 units factor VIII over 10 min. On admission he had no signs of heart failure. INVESTIGATIONS: The ECG showed an acute posterior wall MI. Creatinekinase rose to a maximum of 321 U/l with a significant MB proportion. The echocardiogram demonstrated hypokinesia of the posterior wall. TREATMENT AND COURSE: After initial thrombolysis treatment with a total of 100 mg rtPA according to an accelerated scheme coronary angiography, performed because the symptoms persisted, revealed two-vessel disease. A subtotal stenosis of the right coronary artery was balloon-dilated with good primary results. Regular factor VIII substitution was temporarily administered with the aim of initially achieving high normal levels of factor VIII activity. CONCLUSION: Factor VIII substitution in haemophilia A may promote thrombotic complications. Thrombolytic treatment and balloon angioplasty of acute MI can be successfully performed even in patients with severe haemophilia A.