Showing papers by "Karl-Heinz Kuck published in 2005"

Recovered Pulmonary Vein Conduction as a Dominant Factor for Recurrent Atrial Tachyarrhythmias After Complete Circular Isolation of the Pulmonary Veins Lessons From Double Lasso Technique

Abstract: Background— Atrial tachyarrhythmias (ATa) can recur after continuous circular lesions (CCLs) around the ipsilateral pulmonary veins (PVs) in patients with atrial fibrillation (AF). This study characterizes the electrophysiological findings in patients with and without ATa after complete PV isolation. Methods and Results— Twenty-nine of 100 patients had recurrent ATa after complete PV isolation by use of CCLs during a mean follow-up of ≈8 months. A repeat procedure was performed in 26 patients with ATa and in 7 volunteers without ATa at 3 to 4 months after CCLs. No recovered PV conduction was demonstrated in the 7 volunteers, whereas recovered PV conduction was found in 21 patients with recurrent ATa (right-sided PVs in 9 patients and left-sided PVs in 16 patients). The interval from the onset of the P wave to the earliest PV spike was 157±66 ms in the right-sided PVs and 149±45 ms in the left-sided PVs. During the procedure, PV tachycardia activated the atrium and resulted in atrial tachycardia (AT) in 10...

Electrophysiological Findings During Ablation of Persistent Atrial Fibrillation With Electroanatomic Mapping and Double Lasso Catheter Technique

Abstract: Background— Pulmonary veins (PVs) can be completely isolated with continuous circular lesions (CCLs) around the ipsilateral PVs. However, electrophysiological findings have not been described in detail during ablation of persistent atrial fibrillation (AF). Methods and Results— Forty patients with symptomatic persistent AF underwent complete isolation of the right-sided and left-sided ipsilateral PVs guided by 3D mapping and double Lasso technique during AF. Irrigated ablation was initially performed in the right-sided CCLs and subsequently in the left-sided CCLs. After complete isolation of both lateral PVs, stable sinus rhythm was achieved after AF termination in 12 patients; AF persisted and required cardioversion in 18 patients. In the remaining 10 patients, AF changed to left macroreentrant atrial tachycardia in 6 and common-type atrial flutter in 4 patients. All atrial tachycardias were successfully terminated during the procedure. Atrial tachyarrhythmias recurred in 15 of 40 patients at a median of...

Reduction of myocardial scar size after implantation of mesenchymal stem cells in rats: what is the mechanism?

Abstract: The use of a cellular therapy offers a promising approach for the treatment of heart disease. Besides other precursor cells, bone marrow (BM)-derived stem cells were discovered that migrate into ischemic myocardium and participate in myogenesis as well as angiogenesis. A subpopulation of those are the mesenchymal stem cells (MSC), which may be potential candidates for repairing ischemic heart tissue. MSC are easy to prepare and can be used in an autologous strategy. Here we demonstrate the effect of transplanted MSC in our autologous rat model of myocardial injury. BM was isolated from tibiae and femurs of Wistar rats. After 24 h, the adhering MSC were separated, expanded, retrovirally transduced using green fluorescent protein (GFP), and cloned. A cryo-infarct was generated in the rat hearts, and immediately after this the cells were injected into the border zone of the lesion. After a 10-week follow up, the hearts were excised and the myocardial scar areas were measured using computer-guided morphometry...

Downsizing of the mitral valve and coronary revascularization in severe ischemic mitral regurgitation results in reverse left ventricular and left atrial remodeling.

Abstract: Objective: Data of combined mitral downsizing by restrictive prosthetic ring annuloplasty and coronary artery bypass grafting (CABG) in patients with ischemic cardiomyopathy and moderately severe to severe mitral regurgitation (MR) are rare, and little is known about the effect on reverse left ventricular (LV) and left atrial (LA) remodeling. Methods: Thirty-eight patients (70.6G8.3 years) with coronary artery disease, ischemic cardiomyopathy (LV ejection fraction [LVEF] 31G8%) and moderately severe to severe MR (grade 3.6G0.5) underwent CABG and mitral downsizing by 2–4 ring sizes. Clinical follow-up and serial transthoracic echocardiographic studies were performed after surgery (discharge, 3G 0.5 months, 13G7 months) to assess survival, NYHA class, MR, leaflet coaptation height, LA and LV dimensions/volumes, fractional shortening (FS) and LVEF. Results: Early mortality (!30 days) was 2.6%, survival at follow-up was 92 and 85%, respectively. NYHA class improved from 3.3G 0.6 to 1.5G0.6 (P!0.001). Residual MR at discharge and at follow-up was grade 0.5 and 0.6, respectively (P!0.001). Leaflet coaptation height was 8G1 mm and did not change over time. LV end-diastolic, end-systolic and LA dimensions decreased from 60G 7t o 57G8 mm, from 47G 9t o 42G9 mm and from 51G 5t o 45G4 mm, FS increased from 23G 9t o 28G10% (P!0.001); LV end-diastolic and end-systolic volumes decreased from 188G33 to 171G30 ml and from 129G35 to 105G33 ml, LVEF increased from 31G 8t o 39G10% (P!0.001). Conclusions: Combined mitral downsizing and CABG surgery was performed with excellent clinical results: only minimal residual MR, a significant reduction of LA dimension and an increase of LV contractility due to reverse remodeling were observed. Q 2005 Elsevier B.V. All rights reserved.

Topographic distribution of focal left atrial tachycardias defined by electrocardiographic and electrophysiological data.

Abstract: Background Detailed information about the topographic distribution of focal left atrial tachycardias (FLATs) is limited. Methods and Results A total of 143 atrial tachycardia (AT) foci were successfully ablated in 140 patients (56 men, mean age 44.6{|±17.9 years). In 36.4% (52/143 ATs), a left atrial (LA) origin of the tachycardia was identified from the site of successful ablation. In 46% (24/52) of FLATs, the site of origin (SO) was near the ostium of a pulmonary vein (PV), and in 36.5% (19/52), the SO was near the mitral annulus (MA). In the remaining ATs, the SO was in the left atrial appendage (LAA), septum, LA roof and inside the coronary sinus. P waves in V1 showed biphasic morphology with an initial negative component in most FLATs originating from the septal MA, superior MA, and LAA. However, P waves in V1 were positive in all patients with FLATs originating from PVs. Negative P waves in aVL were always observed in FLATs originating from left PVs. The mean cycle length of FLATs from PVs was significantly shorter than that from the MA. Conclusion Knowledge of the topographic distribution, P-wave morphology, and tachycardia cycle length facilitates successful ablation of FLATs. (Circ J 2005; 69: 205 - 210)

Three years experience with monopolar and bipolar radiofrequency ablation surgery in patients with permanent atrial fibrillation

Abstract: Objective: In our population permanent atrial fibrillation (pAF) is a frequent concomitant problem in patients undergoing open heart surgery. A 3-year experience with a treatment strategy using mono- and bipolar radiofrequency (RF) ablation procedures in a heterogeneous group of patients is reported. Methods: In a prospective analysis the incidence of pAF among all patients undergoing open heart surgery in our department between February 2001 and July 2004 was evaluated. In a second step a selective group of 106 patients with pAF (primary mitral: n=63; aortic: n=24; CABG: n=16; aortic+mitral: n=3) underwent either monopolar (n=86) or bipolar (n=20) RF ablation procedures creating two encircling isolation lesions around the left and the right pulmonary veins (PVs) and a connection line between both. In addition amiodarone was given for 3 months after surgery. Regular follow-ups were performed 3, 6, 9, 12, 18, 24 and 36 months after surgery. Results: The incidence of pAF in the total group of 4.110 patients was 3.6%. While the rate was low in cases without severe heart valve disease (1.1%), a significantly higher presence of pAF in patients scheduled for heart valve surgery (10.3%) was observed (P< 0.0001). The incidence was 30-39% in patients with degenerative and rheumatic mitral valve (MV) disease, and further particularly high in the older aged compared to younger patients (4.2-8.3% at 70-99 years; P<0.001). Hospital mortality after combined open heart and RF ablation surgery was 1.9%. Whereas patients with small left atrial size (LA-diameters <56 mm; n= 59) had SR in almost 90% at follow-up, LA enlargement (LA-diameter ≥56 mm; n = 47) was associated with a significant risk of persisting pAF after surgery (P=0.033, 0.002 and 0.006 at 3, 6 and 9 months follow-up). Conclusion: The use of RF ablation procedures in combination with amiodarone therapy represents a safe and efficient option to cure pAF during open heart surgery in a selective group of patients. The preoperative LA size was of significant importance for the outcome in this investigation.

Complete pulmonary vein isolation guided by three-dimensional electroanatomical mapping for the treatment of paroxysmal atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy.

Abstract: Aims Evaluation of the clinical outcome of patients with hypertrophic obstructive cardiomyopathy (HOCM) and paroxysmal atrial fibrillation (AF) treated with complete pulmonary vein (PV) isolation guided by three-dimensional (3-D) electroanatomical (EA) mapping. Methods Circumferential radiofrequency (RF) ablation and continuous circular lesions (CCLs) around the left and right-sided PVs were performed in 4 highly symptomatic patients (2 males; age 57.5±8.3 years) with HOCM and anti-arrhythmic drug (AAD) refractory paroxysmal AF. Ablation was guided by 3-D EA mapping combined with conventional circumferential PV mapping. The endpoints of the ablation were defined as: (1) absence of all PV spikes documented with the two Lasso catheters within the ipsilateral PVs; and (2) no recurrence of the PV spikes within all PVs following intravenous administration of adenosine. Results The ablation endpoints were achieved in all patients. A repeat ablation was performed in one patient due to repetitive atrial tachycardia, 1 month after the initial procedure. During a follow-up of 5.8±2.7 months, all patients are free of AF recurrence. Short episodes of symptomatic AT were documented after the repeat procedure, and were well controlled with oral amiodarone in the patient. No procedure-related complications were observed. Conclusion The present study demonstrates that complete isolation of ipsilateral PVs guided by 3-D EA mapping is potentially effective for the treatment of highly symptomatic, drug refractory paroxysmal AF in patients with HOCM.

Use of the novel magnetic navigation system Niobe in percutaneous coronary interventions; the Hamburg experience.

Abstract: Introduction: In interventional cardiology an increasing demand to treat complex coronary lesions (i.e. distal lesions, tortuous vessels, chronic occiusions) has developed within the last years. New devices to fulfill this demand are therefore needed. Methods and results: The magnetic navigation system (Niobe System; Stereotaxis Inc.) represents a novel system which allows 3-dimensional control of the guide wire tip using magnetic fields. Two computer controlled permanent magnets on each side of the patient create a uniform magnetic field which can freely be directed. A small magnet at the guide wire tip will align according to the vector of the magnetic field. Advancing and retracting of the wire is to be done manually. The remaining steps of angioplasty (i.e. balloon angioplasty and stent implantation) are performed conventionally, after magnetically guided crossing of the target lesion. The study was performed to proof the feasibility of the technique in the treatment of coronary lesions. Seventy seven patients with 82 coronary lesions underwent magnetic guided coronary interventions. Sixty three lesions (77%) could be crossed successfully using magnetic guidance, 13 more by switching to conventional guide wires. Successful angioplasty (with or without stent implantation) was achieved in 74 lesions (90%). Mean lluoroscopy time was 13,9′8 min. Conclusions: The use of magnetic guidance in coronary interventions is a promising tool to treat complex coronary lesions. With more experience and improved devices (i.e. coated wires, steerable microcatheters) the safety and efficacy of the procedures should be improved.

[ICD therapy 2005--from implantation to follow-up measures].

Abstract: Die erste Implantation eines ICD erfolgte 1980 durch M. Mirowski [1]. Die erste Implantation in Deutschland wurde 1984 durchgefuhrt. Die anfangs verwendeten Gerate hatten epikardiale Elektroden, die eine Thorakotomie erforderlich machten, und einen nicht programmierbaren Detektionsalgorithmus, der werkseitig vorgegeben war. Seit Ende der 80er Jahre stehen ICDs als transvenose Systeme zur Verfugung und sind zu multiprogrammierbaren Mehrkammergeraten mit komplexen Detektionsund Therapiealgorithmen weiterentwickelt worden [2]. Entsprechend ist die Rate von implantierten Zweiund Drei-Kammer-ICDs in den letzten Jahren auf nahezu 60% angestiegen [3]. Dies ist z.T. darauf zuruckzufuhren, dass Patienten mit einer ICD-Indikation in ca. 20–30% der Falle auch eine Indikation fur einen Zweikammerschrittmacher oder fur ein biventrikulares System haben [4, 5], z.T. sind die hohen Implantationszahlen von Zwei-Kammer-ICDs aber auch auf die Annahme gegrundet, dass ein Algorithmus, der auf Informationen aus Vorhof und Ventrikel zuruckgreifen kann, einem Einkammeralgorithmus uberlegen ist [6]. Eine Evidenz fur diese Annahme fehlte bis zur Veroffentlichung der 1+1-Studie, bzw. vorhandene Daten widersprachen dieser Annahme sogar [7, 8]. Diese Aspekte werden in dem Beitrag „Wie viele Elektroden braucht der ICD?“ von A. Schaumann et al. [9] und in dem Beitrag „Kardiale Resynchronisationstherapie“ von C. Stellbrink [10] gewurdigt. Mit komplexeren Geraten und entsprechend niedrigeren Detektionsgrenzen werden die Tachy-kardielast und der Nachsorgeaufwand deutlich groser, wahrend die Langlebigkeit der Gerate hierdurch eher eingeschrankt wird und die Rate von Sondenkomplikationen zunimmt. Daher haben zwei Entwicklungen eingesetzt, die zukunftweisend sind: 1. Die ICD-Therapie wird haufig mit einer medikamentosen antiarrhythmischen Therapie oder einer Ablationsstrategie verbunden als sog. Hybridtherapie. 2. Einige Gerate konnen heute bereits via Telefon nachgesorgt werden und erleichtern damit die Nachsorge. Die Hybridtherapie ist sowohl im Hinblick auf supraventrikulare als auch ventrikulare Tachykardien sinnvoll, um sowohl adaquate als auch inadaquate Therapien zu vermeiden. So kann bereits bei der Implantation eine Hochfrequenzstromablation aller langsamen induzierbaren ventrikularen Tachykardien angestrebt werden. Mit dem ICD werden dann nur noch schnelle ventrikulare Tachykardien adressiert. Diese Hybridtherapie scheint angesichts exzellenter Ergebnisse der HFS-Ablation bei Patienten mit einer koronaren Herzerkrankung angezeigt und wird zurzeit in zwei prospektiven Studien, der SMSund der VTach-Studie, initiiert durch Professor Kuck, AK St. Georg Hamburg, gepruft [11] und in dem Beitrag „Haufige ventrikulare Tachykardie: Antiarrhythmika oder Ablation?” von H. Tanner et al. [12] in diesem Heft besprochen. Bei Patienten, bei denen eine niedrige Detektionsgrenze unumganglich ist, konnen, wie von Klein & Korte vorgeschlagen und in ihrem Beitrag „Inadaquate ICD-Therapien: was tun?“ diskutiert [13], praventiv supraventrikulare Tachykardien, die haufig fur inadaquate ICD-Therapien verantwortlich sind, abladiert werden, wie z.B. Vorhofflattern oder atriale Makro-Reentrytachykardien [14]. Auch Vorhofflimmern, die wohl haufigste Ursache fur inadaquate ICD-Therapien, ist inzwischen einer kurativen Ablationsbehandlung zuganglich [15, 16]. Diese Vorgehensweise bedarf allerdings weiterer prospektiver Untersuchungen, da das Prozedurrisiko, der Nutzen fur den Patienten und die Therapiekosten gegeneinander abgewogen werden mussen. In diesem Zusammenhang wird die elektrophysiologische Untersuchung, die als Voraussetzung der ICD-Implantation zunehmend seltener durchgefuhrt wird (Quick-ICD-Studie, Dr. D. Bansch), eine neue Wertigkeit erfahren. 1Allgemeines Krankenhaus St. Georg, Hamburg

Unusual case of coronary–subclavian steal syndrome

Abstract: A 46 year old man presented with an acute coronary syndrome in October 2003. Coronary angiography revealed severe triple vessel disease and urgent bypass grafting was performed, joining the left internal mammary artery (LIMA) to the left anterior descending artery (LAD). During two attempts to close the thorax, episodes of severe hypotension occurred. These were considered by the surgeons to be associated with the LIMA (vasospasm). Therefore they decided to …