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With an estimated incidence of approximated 36 per 100,000 persons per year, paroxysmal supraventricular tachycardias form a relevant clinical set of problems. They occur based on different substrates with varied symptoms and electrocardiographic items. The 12-channel ECG depicts the background to determine the underlying pathomechanism. The sinus node and all components of the conduction system such as atrial myocardium can be involved. Vagal maneuvers, several pharmacological strategies and various ablation technology are available for acute therapy.

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Pulmonary hypertension is newly defined as an elevation of the mean pulmonary arterial pressure >20 mmHg and a pulmonary vascular resistance ≥3 Wood units. Arrhythmias are an increasing problem in patients with pulmonary hypertension. Pathophysiological aspects leading to supraventricular arrhythmias are atrial fibrosis caused by increased right atrial pressure and dilation. An increased sympathetic tone leads to prolongation of action potential and delayed polarisations causing arrhythmias. Therapy of arrhythmias includes drugs (preferred amiodarone) and electrophysiological therapy like electric cardioversion and ablation, which is safe in patients with pulmonary hypertension.

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BACKGROUND: Sudden cardiac death (SCD) accounts for approximately 30 % in patients with pulmonary arterial hypertension (PAH). The exact circumference for SCD in this patient population is still unclear. Malignant cardiac arrhythmias are reported to be rarely present. There are no systematic data concerning long-term electrocardiographic (ECG) recording in patients with PAH. OBJECTIVES: We sought to investigate the rate of potentially relevant arrhythmias in patients with pulmonary hypertension (PH). METHODS: Consecutive patients without diagnosis of known cardiac arrhythmias followed in our outpatient clinic for PH were enrolled in the study. All patients underwent a 72-h Holter ECG. Clinical data, 6-min walk distance, laboratory values, and echocardiography were collected/performed. RESULTS: Ninety-two consecutive patients (New York Heart Association class (NYHA) III/IV: 65.2 %/5.4 %, PH Group 1: 35.9 %, Group 3: 10.9 %, Group 4: 28.3 %, Group 5: 2.2 %) were investigated. Relevant arrhythmias were newly detected in 17 patients: non-sustained ventricular tachycardia (n = 12), intermittent second-degree heart block (n = 1), intermittent third-degree heart block (n= 3), and atrial flutter (n = 1). Echocardiographic systolic pulmonary pressure and diameter of the right heart were elevated in patients with relevant arrhythmias. Right heart catheterization revealed higher pulmonary vascular resistance (672 vs. 542 dyn · s · cm(-5), p = 0.247) and lower cardiac index (2.46 vs. 2.82 l/min/m(2), p = 0.184). CONCLUSIONS: Ventricular tachycardias occur more often in PH patients than previously reported. However, the prognostic relevance of non-sustained ventricular tachycardias in this cohort remains unclear. As a large number of PH patients die from SCD, closer monitoring, e.g., using implantable event recorders, might be useful to identify patients at high risk.

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BACKGROUND AND AIMS: Capsule endoscopy is an established tool for investigation of the small intestine. Because of limited clinical experience in patients with cardiac devices the US Food and Drug Administration and the manufacturers recommend not to use capsule endoscopy in these patients. METHODS: Studies investigating possible interference between small bowel capsule endoscopy and cardiac pacemakers and implanted cardioverters were analysed. For the review we considered studies published in English or German and indexed in PubMed (Medline) as well as relevant abstracts and technical data from the manufacturer. RESULTS: In vitro and in vivo studies applying real capsules revealed no clinically relevant interference with pacemakers and implanted cardioverters. This evidence already has had an impact on clinical practice and recommendations of scientific societies. On the other hand wireless telemetry can interfere with CE video. CONCLUSION: According to present evidence, small bowel capsule endoscopy can be used in patients with pacemakers and implanted cardioverters after obtaining informed consent concerning the formal existence of contraindication.

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AIMS: Troponin I (TNI) is an established marker for the diagnosis of acute coronary syndrome (ACS). The study evaluated if (induced) tachycardiac arrhyhthmias within the scope of the electrophysiological studies (EPS) led to elevation of TNI serum levels. METHOD: TNI was measured in the serum of 28 patients before and after the EPS. The left ventricular ejection fraction (LV-EF) was investigated by two-dimensional echocardiography. Left ventricle hypertrophy (LVH) was measured according to the recommendations of the American Society of Echocardiography. All patients underwent coronary angiography prior to the EPS, and significant coronary heart disease was defined as stenosis > 50%. The EPS revealed supraventricular and ventricular tachycardias using the 18-step protocol with one, two, and three extrastimuli. RESULTS: Indications for the EPS were syncope (n = 15), atrioventricular tachycardia (n = 4), non-sustained VT (n = 6), and sustained VT (n = 3). Coronary heart disease (CHD) was detected in 8 patients (1-vessel: n = 3; 2-vessel: n = 4; 3-vessel: n = 1), and 2 patients underwent percutaneous coronary intervention before EPS. Echocardiography revealed normal LV-EF in 18 patients and a reduction in the others (low n = 3, middle n = 5, high n = 2). Thirteen patients suffered from LVH. In 2 patients, external cardioversion was required during the EPS. TNI was elevated over 0.1 ng/ml (risk stratification cut-off for ACS) in 4 patients before and in 12 patients after EPS. There was no relationship between LV-EF, CHD, and the elevation of TNI after the EPS. CONCLUSION: TNI can be elevated by (induced) tachycardias within the scope of electrophysiological studies without a relationship to LV-EF, LVH, and CHD.

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We present a patient with an accessory pathway difficult to ablate in the right free wall. Two prolonged and failed attempts at radiofrequency catheter ablation of this accessory pathway in other institutions led to a third attempt in our hospital. Successful outcome of accessory pathway ablation was achieved by mapping the right free wall using an intracoronary catheter in the right coronary artery. A long vascular sheeth was introduced in the right femoral vein, manipulated into the tricuspid anulus, which allowed a stable catheter position with adequate tissue contact of the ablation catheter at the target site. The combination of exact mapping and adequate tissue contact of the ablation catheter as described above facilitated successful outcome in this patient. Further investigation is necessary to determine the role of this technique as first choice therapy in patients prone to develop recurrence of accessory pathway conduction or primary failure of catheter ablation.

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We present the case of a 44 year old woman with recurrent episodes of supraventricular tachycardia due to AV-nodal reentry (AVNRT). She was refractory to conventional medical treatment and referred to our hospital with the view to catheter ablation of the slow AV-nodal pathway. AVNRT of the common type was easily induced performing stimulation from the high right atrium and proximal coronary sinus. Other forms of supraventricular tachycardia were definitely ruled out during further electrophysiologic study. Repetitive RF applications around the right posteroseptal region failed to cure the tachycardia which remained inducible with a typical jump in the AH interval. Extensive RF applications from posteroinferior to the midseptum including the area of the proximal coronary sinus and its os were ineffective as well.AVNRT was transiently but reproducibly eliminated while burns were applied to the high midseptum but AVNRT reoccured within 20 minutes. Finally after retrograde passage of the aortic valve with a 4 mm tip ablation catheter, RF was applied to the left postero to midseptal region. An accelerated junctional rhythm was immediately observed and AVNRT remained non-inducible from that time onwards. It is concluded that an atypical posterior extension of the AV node with predominant leftatrial course might be responsible for this unusual success of slow pathway elimination from left posteroseptal.

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We report a case of an artificial fistula between the internal thoracic artery and vein after coronary artery bypass surgery, anastomosing the left internal thoracic artery to the LAD. Because of symptomatic anterior wall ischaemia due to coronary steal a treatment was mandatory. Instead of surgical correction, this shunt was closed by coil embolization of the venous limb.

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We present a case of WPW syndrome with an accessory pathway in the right free wall. Two prolonged and failed attempts at radiofrequency catheter ablation of this accessory pathway in other institutions led to a third attempt in our hospital. With a 7F catheter in the right coronary artery, transient ischemia in the right ventricular myocardium developed with consecutive loss of bidirectional preexcitation within 45 seconds prior to catheter ablation. Removal of the guiding catheter, while the mapping catheter in the coronary artery was still in place, was reproducibly followed by the reoccurrence of the preexcitation pattern. Successful outcome of accessory pathway ablation was achieved by mapping the right free wall using an intracoronary catheter in the right coronary artery and ablating the accessory pathway using a modified long vascular sheet.

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Adenosine is generally considered to be safe and effective in treatment of orthodromic circus movement tachycardia in patients with accessory pathways. We present a case with reproducible induction of atrial fibrillation after initial successful termination of orthodromic circus movement tachycardia using a left sided accessory pathway by adenosine. With the induction of atrial fibrillation sudden onset of preexcitation with subsequent rapid ventricular response was accompanied by moderate hemodynamic compromise. Before and after successful ablation of the accessory pathway, adenosine was not able to induce atrial fibrillation when applied during sinus rhythm. Adenosine induced atrial fibrillation is due to shortening of the atrial action potential duration and atrial refractoriness, whereas shortening of the antegrade refractory period in the accessory pathway leads to rapid conduction to the ventricles. Thus, care should be taken using adenosine in patients with orthodromic circus movement tachycardias and evidence of antegrade preexcitation during sinus rhythm.

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The idiopathic long QT syndrome (LQTS) carries a high mortality in untreated patients. Administration of beta-receptor antagonists is considered the treatment of choice. Data concerning the usefulness of implantable cardioverter-defibrillator (ICD) therapy in this condition are sparse. We report on a 29-year-old female with LQTS who was treated with propranolol, but also underwent implantation of an ICD as a fail-safe therapy. During the next 17 months, the patient was asymptomatic. However, after skipping her propranolol for 3 days, she had several syncopal spells with concomitant device therapy. ICD interrogation revealed a total of 55 nonsustained runs of ventricular tachycardia and 16 sustained episodes that were correctly identified by the device and respectively terminated by the first shock. This case report demonstrates that in selected patients with the LQTS, using ICD therapy as a fail-safe treatment may be life-saving, particularly when compliance to medical therapy is uncertain.

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With the frequent use and excellent longevity of the internal mammary artery graft, knowledge about the behaviour of this graft under different conditions is becoming relevant. We studied 20 patients with combined two-dimensional and pulsed Doppler sonography before and after exercise testing and established values for peak velocities and flow duration. During exercise flow duration shortened in systole and diastole by the same order of magnitude, while peak diastolic velocity especially increased during exercise.

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In a group of 22 patients, Doppler signals from the proximal part of the internal mammary artery graft were studied from the supraclavicular fossa as well as from the high intercostal spaces. An adequate signal was found more often from the supraclavicular position. Both positions showed higher peak systolic than peak diastolic velocities. Transition of the flow to the typical coronary flow pattern with higher peak diastolic velocity seems to occur in lower parts of the graft.

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Internal mammary artery grafting to the left anterior descending artery gives higher long-term patency and improved survival as compared with venous grafts. Few data exist on the operative mortality and infarction rate in coronary artery bypass surgery when using this type of graft in high-risk groups, such as patients with left main stenosis. In 19 months, we studied 81 consecutive patients with left main stenosis who received a mammary artery graft to the left anterior descending artery as well as vein grafts to other vessels and found no excessive mortality or infarction rate. We suggest that patients with left main stenosis should be treated with an internal mammary artery graft.

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The noninvasive examination of internal mammary artery grafts is gaining importance with the increasing use of this vessel in the surgical treatment of coronary atherosclerosis of the left anterior descending artery. We studied 36 patients (37 internal mammary artery grafts) with combined two-dimensional and pulsed Doppler echography from the supraclavicular fossa. Adequate visualization and Doppler signals were obtained in 95% of arterial grafts. Twenty-four grafts leading to an area without evidence of old myocardial infarction or ischemia and 10 grafts leading to an area of old myocardial infarction but without evidence of ischemia on exercise showed a significant decrease of the peak systolic velocity and of the peak systolic velocity/peak diastolic velocity ratio as compared to the controls, which consisted of the contralateral internal mammary arteries in situ. One patient with a distally subtotally occluded mammary artery graft had a flow pattern different from the other bypassed mammary arteries. It seems that combined two-dimensional and pulsed Doppler echography is a useful method to evaluate the functional status of internal mammary artery grafts.

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