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J Tebbenjohanns

Publications and source records attributed to J Tebbenjohanns.

At least 19 recordsLinked to original sources
PubMed2003

[Therapy of atrial fibrillation].

Atrial fibrillation is the most common cardiac arrhythmia in adults. Paroxysmal atrial fibrillation terminates spontaneously, whereas the persistent form terminates only after medical or electrical cardioversion. Permanent atrial fibrillation cannot be cardioverted. Restoration of sinus rhythm can be achieved by antiarrhythmic drugs or electrical cardioversion, both performed under continuous electrocardiographic monitoring. If atrial fibrillation has lasted longer than 48 hours or the precise time of onset cannot be determined, there are two alternative approaches: systemic anticoagulation to achieve an international normalised ratio (INR) of 2.0 to 3.0 for at least three weeks, followed by cardioversion; or cardioversion guided by transesophageal echocadiography indicating the absence of thrombus. Several drugs have been shown to be effective for the maintenance of sinus rhythm. Anticoagulant therapy is mandatory for a minimum of three weeks after cardioversion. In case of drug refractory, highly symptomatic atrial fibrillation the indication for radiofrequency catheter ablation should be discussed, although the value of this new method is still under evaluation.

Anti-Arrhythmia Agents↗
PubMed2001

Transvenous biventricular defibrillation halves energy requirements in patients.

BACKGROUND: Defibrillation thresholds (DFT) with standard implantable cardioverter-defibrillator leads in the right ventricle (RV) may be determined by weak shock field intensity in the myocardium of the left ventricle (LV). Adding a shocking electrode in a coronary vein on the middle of the LV free wall, thereby establishing biventricular defibrillation, substantially reduced defibrillation requirements in animals. We investigated the feasibility of this approach in 24 patients receiving an implantable cardioverter-defibrillator using a prototype over-the-wire temporary LV defibrillation lead. METHODS AND RESULTS: The LV lead was inserted through the coronary sinus, using a guide catheter and guidewire, into a posterior or lateral coronary vein whose location was determined by retrograde venography. Paired DFT testing compared a standard system (RV to superior vena cava plus can emulator [SVC+Can], 60% tilt biphasic shock) to a system including the LV lead. The biventricular system was tested with a dual-shock waveform (20% tilt monophasic shock from LV-->SVC+Can, then 60% tilt biphasic shock from RV-->SVC+Can). Twenty patients completed DFT testing. Venography and LV lead insertion time was 46+/-40 minutes. The biventricular system reduced mean DFT by 45% (8.9+/-1.1 J versus 4.9+/-0.5 J, P<0.001). Twelve patients (60%) had a standard system DFT >/=8 J, and the biventricular system gave a lower DFT in all patients. There were no adverse events related to the use of the LV lead, which was removed after testing. CONCLUSIONS: Internal defibrillation using a transvenously inserted LV lead is feasible, produces significantly lower DFTs, and seems safe under the conditions tested. Biventricular defibrillation may be a useful option for reducing DFTs or could be added to an LV pacing lead for heart failure.

Coronary Angiography↗
PubMed2001

Investigation of coronary venous anatomy by retrograde venography in patients with malignant ventricular tachycardia.

BACKGROUND: The coronary venous system is increasingly used for left ventricular or biventricular pacing in patients with severe heart failure. The present study investigated the structure of the coronary veins in patients presenting with structural heart disease and malignant ventricular tachyarrhythmias. The availability of veins for possible lead placement was assessed. METHODS AND RESULTS: The number, relative size, and location of coronary veins were evaluated by retrograde venography in 129 patients undergoing cardioverter-defibrillator implantation. Detailed x-ray image analysis was performed in 86 patients, for whom optimal coronary sinus occlusion and vein visualization was achieved. The anterior interventricular vein and the middle cardiac vein were visible in 85 (99%) of 86 patients and in 86 (100%) of 86 patients, respectively. Between these 2 veins, at least 1 additional prominent vein was visible in 85 (99%) of 86 patients. Just 1 vein was present in 44 (51%) of 86 patients. Two veins were observed in 40 (46%) of 86 patients, and >2 veins were visualized in 2 (2%) of 86 patients. Venous anatomy allowed positioning of a 0.014-in guidewire in a coronary vein in 115 (93%) of 124 patients. CONCLUSIONS: The presence, diameter, angulation, and tortuosity of veins as visualized by retrograde venography determine their acceptability for the placement of a lead in a predetermined location. Despite the considerable variability of the coronary venous system among patients, a lateral vessel for lead introduction was available in 82%, and a posterior or lateral vessel was available in 99% of individuals within a patient population that could potentially benefit from a lead on the left ventricle.

Aged↗
PubMed2001

Atrial reentrant tachycardia after surgery for congenital heart disease: endocardial mapping and radiofrequency catheter ablation using a novel, noncontact mapping system.

BACKGROUND: The purpose of the present study was to determine the role of a novel, noncontact mapping system for assessing a variety of atrial reentrant tachycardias (ART) in patients after the surgical correction of congenital heart disease. METHODS AND RESULTS: In 14 patients, an electrophysiological study using the Ensite 3000 system was performed to assess ARTs resistant to medical treatment. Sixteen different forms of ART were inducible in the 14 patients studied. The reentrant circuit of all ARTs could be characterized and localized with respect to anatomic landmarks such as atriotomy scars, intraatrial patches/baffles, and cardiac structures. In 15 of the 16 ARTs (in 13 of the 14 patients), a target area of the reentrant circuit for radiofrequency current application (ie, an area of conduction between 2 anatomical obstacles such as surgical barriers and cardiac structures of electrical isolation) could be localized within the systemic venous atrium. Nine patients exhibited macroreentry, and 4 showed microreentry. In 12 patients, ART could be terminated by creating linear radiofrequency current lesions (75 degrees C, 180 to 390 s). Completeness of linear lesions after radiofrequency current delivery was proven by analyzing color-coded isopotential maps of atrial activation while applying atrial pacing techniques. The mean duration of the procedures was 286 minutes (range, 130 to 435 minutes); fluoroscopy time ranged from 7 to 33.8 minutes (mean, 17.4 minutes). CONCLUSIONS: In patients with ART after the surgical correction of congenital heart disease, the use of the noncontact mapping system allows for characterization of the tachycardia and guidance for effective radiofrequency current delivery.

Adolescent↗
PubMed2001

[Usefulness of a VDD defibrillation electrode in recording atrial electrograms during atrial flutter and atrial fibrillation].

BACKGROUND: Monitoring of atrial signals improves the accuracy in identifying supraventricular tachyarrhythmias to prevent inappropriate therapies in patients with implantable cardioverter-defibrillators (ICD). Since complications due to the additional atrial lead were found in dual chamber ICD systems with 2 leads, we designed a single-pass VDD-lead for use with dual chamber ICDs. PATIENTS AND METHODS: After promising animal experiments in a German multicenter study a prototype VDD lead (single-coil defibrillation electrode with 2 additional fractally coated rings for bipolar sensing in the atrium) was temporarily used in 20 patients. Atrial and ventricular signals were recorded during sinus rhythm, atrial flutter, atrial fibrillation and ventricular tachycardia or ventricular fibrillation. Terminations of ventricular arrhythmias were performed by internal DC shock. RESULTS: The implantation of the electrode was successful in 18 of 20 patients. Mean atrial pacing threshold was 2.45 +/- 0.9 V/0.5 ms, mean atrial impedance was 215 +/- 31 Ohm. Atrial amplitudes were greater during sinus rhythm (2.7 +/- 1.6 mV) than during atrial flutter (1.36 +/- 0.28 mV, p < 0.05) or atrial fibrillation (0.92 +/- 0.29 mV, p < 0.01). During ventricular fibrillation atrial "sinus"-signals had significantly (p < 0.01) lower amplitudes than during sinus rhythm. Mean ventricular sensing was 13.3 +/- 7.9 mV, mean ventricular impedance was 577 +/- 64 Ohm. Defibrillation was successful with 20 J shock. 99.6% of P waves could be detected in sinus rhythm and 85 +/- 9.9% of flutter waves during atrial flutter. During atrial fibrillation 55% of atrial signals could be detected without modification of the signal amplifier. CONCLUSIONS: A new designed VDD dual chamber electrode provides stable detection of atrial and ventricular signals during sinus rhythm and atrial flutter. For reliable detection of atrial fibrillation modifications of the signal amplifier are necessary.

Aged↗
PubMed2001

Prospective evaluation of catheter ablation in patients with implantable cardioverter defibrillators and multiple inappropriate ICD therapies due to atrial fibrillation and type I atrial flutter.

The high incidence of inappropriate therapies due to drug refractory supraventricular tachycardia remains a major unsolved problem of the ICD. Most of the inappropriate therapies for supraventricular tachycardia are caused by AF and type I atrial flutter with rapid ventricular response. The purpose of this prospective study was to determine the usefulness of AVN modulation or ablation for rapid AF and ablation of the tricuspid annulus-inferior vena cava (TA-IVC) isthmus for type I atrial flutter in ICD patients with frequent inappropriate ICD interventions. Eighteen consecutive patients were enrolled in this study. Twelve patients received a mean of 34 +/- 36 antitachycardia pacing (ATP) and 41 +/- 32 shock therapies for rapid AF during 49 +/- 39 months, and 6 patients a mean of 111 +/- 200 ATP and 11 +/- 8 shock therapies for type I atrial flutter during 52 +/- 37 months preceding ablation procedure. Modification of the AVN was successful in 10 (83%) of 12 AF patients, in 2 (17%) patients ablation of the AVN was performed. A complete TA-IVC isthmus block was achieved in 5 (83%) of 6 atrial flutter patients. Three (25%) AF patients had 11 +/- 24 recurrences of ATP and 0.4 +/- 1.1 shock therapies for rapid AF during 15 +/- 7 months. None of the atrial flutter patients had recurrences of inappropriate therapies for type I atrial flutter during 14 +/- 8 months, but two (33%) patients had inappropriate ICD therapies for type II atrial flutter or rapid AF. There was an overall mean incidence of 18 +/- 22 inappropriate ICD therapies per 6 months before and 4 +/- 9 per 6 months after the ablation procedure (P < 0.05). In conclusion, radiofrequency catheter modification or ablation of the AVN for rapid AF and ablation for atrial flutter type I are demonstrated to be highly effective in the majority of ICD patients with drug refractory multiple inappropriate ICD therapies.

Aged↗
PubMed2001

Multicenter experiences with a single lead electrode for dual chamber ICD systems.

Monitoring of atrial signals improves the accuracy in identifying supraventricular tachyarrhythmias to prevent inappropriate therapies in patients with implantable ICDs. Since difficulties due to the additional atrial lead were found in dual chamber ICD systems with two leads, the authors designed a single pass VDD lead for use with dual chamber ICDs. After a successful animal study, the prototype VDD lead (single coil defibrillation lead with two additional fractally coated rings for bipolar sensing in the atrium) was temporarily used in 30 patients during a German multicenter study. Atrial and ventricular signals were recorded during sinus rhythm (SR), atrial flutter, AF, and VT or VF. The implantation of the lead was successful in 27 of 30 patients. Mean atrial pacing threshold was 2.5 +/- 0.9 V/0.5 ms, mean atrial impedance was 213 +/- 31 ohms. Atrial amplitudes were greater during SR (2.7 +/- 1.6 mV) than during atrial flutter (1.46 +/- 0.3 mV, P < 0.05) or AF (0.93 +/- 0.37 mV, P < 0.01). During VF atrial "sinus" signals had significantly (P < 0.01) lower amplitudes (1.4 +/- 0.52 mV) than during SR. The mean ventricular sensing was 13.3 +/- 7.9 mV and mean ventricular impedance was 577 +/- 64 ohms. Defibrillation was successful with a 20-J shock in all patients. In addition, 99.6% of P waves could be detected in SR and 84.4% of flutter waves during atrial flutter. During AF, 56.6% of atrial signals could be detected without modification of the signal amplifier. In conclusion, a new designed VDD dual chamber lead provides stable detection of atrial and ventricular signals during SR and atrial flutter. Reliable detection of atrial signals is possible without modification of the ICD amplifier.

Aged↗
PubMed2000

Absorption and hemodynamic effects of airway administration of adrenaline in patients with severe cardiac disease.

BACKGROUND: If intravenous access cannot be attained during resuscitation of adult patients, endotracheal application of at least 2 mg of adrenaline is recommended. However, the effects of this intervention have not yet been demonstrated in adults. OBJECTIVE: To demonstrate the effects of adrenaline administered through the airways. DESIGN: Prospective clinical trial. SETTING: Operating theater at university hospital. PATIENTS: 34 patients receiving implantable cardioverter defibrillators under general anesthesia. INTERVENTION: When mean arterial pressure decreased below 80 mm Hg, 100 times the effective central intravenous dose of adrenaline (mean +/- SD, 1.3+/-0.6 mg [range, 0.7 to 3 mg]) was administered over 5 seconds into the endotracheal tube or through a bronchial catheter. Ten forced ventilations followed. MEASUREMENTS: Hemodynamic variables were recorded with a polygraph recorder. Adrenaline levels were measured in 13 patients. RESULTS: Plasma levels and arterial pressure increased in all patients (P < 0.002). Higher plasma levels (P < 0.039) and greater arterial pressure (P < 0.001) were achieved with this method than with intravenous injection. The effects of adrenaline did not differ between the two airway routes. Sustained ventricular arrhythmia did not occur. CONCLUSION: These substantial effects support the standard recommendation to consider the airways as an alternate route for at least 2 mg of adrenaline during resuscitation.

Absorption↗
PubMed2000

Radiofrequency ablation of atrioventricular nodal reentrant tachycardia: mechanisms and recurrence rate.

Radiofrequency catheter ablation is the treatment of choice in atrioventricular nodal reentrant tachycardia. Electrophysiologic investigations in 623 patients revealed eight mechanisms of tachycardia ablation: Ablation of fast (I) or slow (II), modification of fast (III) or slow AV nodal pathways (IV), modification of both pathways (V), ablation of fast and modification of slow (VI), ablation of slow and modification of fast pathways (VII) and ablation of both pathways (VIII). The criteria of diagnosis of these eight mechanisms of tachycardia ablation are described. Follow-up showed fewer relapses in patients with ablation (0-2%) in comparison to patients with modification of a single AV nodal pathway (8-12%). Alteration of both pathways includes an increasing risk of total AV nodal block, which occurred in 7 patients (1.1%). Detailed analysis of the mechanism of catheter ablation is recommended in all patients after radiofrequency current delivery for AV nodal reentrant tachycardia to estimate the risk of relapse during follow-up or development of total AV block in the particular patient in case of a further ablation procedure.

Catheter Ablation↗
PubMed2000

[Supraventricular tachycardia in infants, children and adolescents: diagnosis, drug and interventional therapy].

Supraventricular tachycardias are the most frequent forms of symptomatic tachyarrhythmias in infants, children and adolescents. Clinical symptoms depend on age and underlying cardiac anatomy. Newborn babies and infants with paroxysmal atrioventricular reentrant tachycardias usually present with signs of congestive heart failure due to rapid heart rate. In older children and adolescents, palpitations are the leading symptom. Patients with chronic-permanent tachycardias (i.e., atrial ectopic tachycardia, permanent form of junctional reciprocating tachycardia) often develop a secondary form of dilated cardiomyopathy, the so-called "tachymyopathy". Adenosine has evolved as the drug of choice in any age group for the termination of atrioventricular reentrant tachycardia of any origin. In addition, it serves as a diagnostic tool in primary atrial tachycardias. Long-term management of atrioventricular reentrant tachycardia in infancy and childhood is age dependent. In newborn babies and infants, pharmacological therapy is advised due to the high spontaneous cessation rate of those tachycardias at the end of the first year of life. In contrast to this, the probability of spontaneous cessation of tachycardia in children > 1 year of age is very low. Therefore, radiofrequency catheter ablation of the anatomical substrate of the tachycardia is a rational alternative to long-lasting antiarrhythmic therapy. Results in children with a structurally normal heart are comparable to those achieved in adults. In patients with congenital heart disease and supraventricular tachycardias, catheter ablation during preoperative cardiac catheterization is recommended. Atrial reentrant tachycardias have been identified as one major risk factor for late postoperative morbidity and mortality in young patients. Pharmacological therapy is often not sufficient to control the tachycardia. In addition, underlying sinus node dysfunction may be aggravated in a considerable portion of the patients affected. Catheter ablation based on conventional endocardial mapping techniques by multipolar electrode catheters with the aim of identifying the critical region of the reentrant circuit is associated with an impaired success rate and a considerable recurrence rate. It may be assumed that, using the modern mapping techniques currently available (electroanatomical mapping and non-contact mapping), results of radiofrequency catheter ablation of atrial reentrant tachycardias after surgical correction of congenital heart disease will be significantly improved within the next few years.

Acute Disease↗
PubMed2000

Bimodal RR interval distribution in chronic atrial fibrillation: impact of dual atrioventricular nodal physiology on long-term rate control after catheter ablation of the posterior atrionodal input.

INTRODUCTION: Radiofrequency (RF) catheter modification of the AV node in patients with atrial fibrillation (AF) is limited by an unpredictable decrease of the ventricular rate and a high incidence of permanent AV block. A bimodal RR histogram has been suggested to serve as a predictor for successful outcome but the corresponding AV node properties have never been characterized. We hypothesized that a bimodal histogram indicates dual AV nodal physiology and predicts a better outcome after AV node modification in chronic AF. METHODS AND RESULTS: Thirty-seven patients were prospectively subdivided into two groups according to the RR histogram of 24-hour ECG monitoring. Before to RF ablation, internal cardioversion and programmed stimulation were performed. Among the 22 patients (group I) with a bimodal RR histogram, dual AV nodal physiology was found in 17 (77%) patients. Ablation significantly decreased ventricular rate with loss of the peak of short RR cycles after ablation (mean and maximal ventricular rates: 32% and 35% rate reduction, respectively; P < 0.01). In 15 patients with a unimodal RR histogram (group II), dual AV nodal physiology was found in 2 (13%), and rate reductions were 16% and 17%, respectively. At 6 months, 3 (14%) patients in group I and 6 (40%) in group II underwent elective AV nodal ablation with pacemaker implantation due to intolerable rapid ventricular response to AF. CONCLUSION: Bimodal RR interval distribution during chronic AF suggests the presence of dual AV nodal physiology and predicts a better outcome of RF ablation of the posterior atrionodal input.

Adult↗
PubMed1999

Temperature response following nontraumatic low power radiofrequency application.

A marker for the efficiency of heating would be helpful in radiofrequency ablation of tachyarrhythmias. We hypothesized that changes of the catheter tip temperature during nontraumatic, very low power radiofrequency exposure would correlate with the temperature achieved during radiofrequency ablation, and therefore, could be used as a marker for heating efficiency. In 71 ablation attempts for drug refractory supraventricular tachycardias, the catheter tip temperature response to a 1-W-5-second test pulse was measured. Subsequently at the same site, radiofrequency current was delivered with a target temperature of 70 degrees C and a power limit of 50 W. The test pulse, with a measured power level of 1.62 +/- 0.28 W, resulted in a heating efficiency of 0.78 +/- 0.60 degree C/W. During ablation, the achieved tip temperature was 52.9 +/- 7.5 degrees C, requiring a power output of 40.7 +/- 10.9 W. The heating efficiency was 0.57 +/- 0.74 degree C/W. The correlation between heating efficiency at low power and during radiofrequency ablation was linear with a correlation coefficient of 0.88. Regression analysis demonstrated that a heating efficiency above 1 degree C/W predicts a mean ablation temperature above 50 degrees C with more than 95% confidence interval. The temperature response to a very low power radiofrequency application correlates with the temperature rise achieved during radiofrequency ablation. It is suggested that delivery of low power radiofrequency current could be used to determine and monitor efficiency of heating during catheter mapping and ablation procedures.

Catheter Ablation↗
PubMed1999

Noninvasive diagnosis in patients with undocumented tachycardias: value of the adenosine test to predict AV nodal reentrant tachycardia.

INTRODUCTION: Patients with symptoms suggestive of paroxysmal supraventricular tachycardia (PSVT) but no tachycardia documentation often undergo diagnostic electrophysiologic study. In dual AV node physiology with AV node reentrant tachycardia (AVNRT), the anterograde fast pathway is more sensitive than the slow pathway to the effects of adenosine. The purpose of the study was to test the hypothesis that adenosine can be used as a bedside test for the diagnosis of dual AV node physiology and hence for AVNRT. METHODS AND RESULTS: During electrophysiologic study, 37 patients without prior documentation but symptoms indicative for PSVT received incremental dosages of adenosine during sinus rhythm until second-degree or greater AV block was observed. Suggestive signs of dual AV node physiology on the surface ECG (sudden jump of PQ interval > or = 50 msec) were found in 13 (76%) of 17 patients with inducible AVNRT but in only 1 (5%) of the remaining patients (P < 0.01). In the AVNRT group, the maximal increase of the PQ interval between two beats was greater (88+/-45 msec) than in the remaining 20 patients (17+/-11 msec) (P < 0.01). CONCLUSION: Careful evaluation of surface ECG during administration of adenosine helps to identify patients prone to AVNRT. The adenosine test is a valuable noninvasive adjunct in patients with undocumented palpitations suggestive of PSVT.

Adenosine↗