Simon Hönig

Acute Results of Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation Using a Single Mesh Catheter

Introduction: Catheter‐based pulmonary vein isolation (PVI) is an established therapy to treat patients with paroxysmal atrial fibrillation. We evaluated the efficacy of a simplified interventional procedure for PVI by using a single mesh catheter for mapping as well as ablation and with guidance of fluoroscopic imaging only.

64-Detector CT Angiography in Renal Artery Stent Evaluation: Prospective Comparison with Selective Catheter Angiography

PURPOSE To prospectively assess the diagnostic accuracy of 64-detector computed tomographic (CT) renal artery (RA) angiography for the evaluation of RA in-stent restenosis (ISR) by using selective catheter RA angiography as the reference standard. MATERIALS AND METHODS Institutional review board approval and written informed consent were obtained. Eighty-six patients (46 men, 40 women; mean age +/- standard deviation, 71 years +/- 9) with 95 RA stents were examined with 64-detector CT RA angiography by experienced radiologists 1 day before selective catheter RA angiography was performed by experienced cardiologists. Each group was blinded to the results of the other imaging method. For image reconstruction, a standard (B25f) and an edge-enhancing (B46f) kernel were chosen. An ISR of more than 50% was considered as hemodynamically significant. Sensitivity, specificity, and positive and negative predictive values for the detection of ISR by using CT RA angiography were calculated. RESULTS At CT RA angiography, 93 (98%) of 95 stents were assessable for diagnosis. Two stents could not be evaluated owing to hardening artifacts affected by vessel calcifications. All nine cases of significant ISR seen at selective catheter RA angiography were correctly diagnosed by using CT RA angiography, giving a sensitivity of 100% and a negative predictive value of 100%. One case of nonsignificant ISR seen at selective catheter RA angiography was interpreted as significant by using CT RA angiography, giving a specificity of 99% and a positive predictive value of 90%. In four of 78 patients without ISR seen at selective catheter RA angiography, CT RA angiography showed nonsignificant ISR, giving a specificity of 95% and a positive predictive value of 56%. CONCLUSION Sixty-four-detector CT RA angiography can provide an excellent noninvasive technique to help detect and evaluate ISR within the RA stents used in our study.

One-year follow-up after pulmonary vein isolation using a single mesh catheter in patients with paroxysmal atrial fibrillation.

BACKGROUND Catheter-based pulmonary vein (PV) isolation has emerged as established therapy for patients with paroxysmal atrial fibrillation (AF). OBJECTIVE The purpose of this study was to determine the results at 1-year follow-up after PV isolation was performed using a single novel multipolar catheter for mapping and ablation. METHODS Patients with paroxysmal AF were screened by cardiac computed tomography for anatomic suitability to undergo PV ablation with the Bard HD Mesh Ablator Catheter (MESH). PV isolation with the MESH was performed only in patients who matched the criteria of four clearly separated PVs with an ostial diameter of 15 to 25 mm. RESULTS PV isolation with the MESH was performed in 36 (55%) of 65 screened patients. In all 36 patients, all PVs could be mapped with the MESH. Electrical isolation could be achieved in 135 (96%) of 140 PVs that revealed PV potentials. One-year follow-up was completed for 35 patients; one patient was lost to follow-up. Ten (29%) patients reported to be symptom-free and had no AF during three 48-hour ECGs, whereas 25 (71%) patients suffered from AF recurrences. Reablation performed in 11 patients revealed reconnection of three PVs in 6 patients and four PVs in 5 patients. CONCLUSION The single-catheter approach using the MESH for mapping and ablation was associated with a high AF recurrence rate within the first year despite a high acute success rate. Thus, the minimalist complexity of the procedure must be balanced with the poor clinical success leading to a high number of second procedures.

Pre-injection of magnesium sulfate enhances the efficacy of ibutilide for the conversion of typical but not of atypical persistent atrial flutter

BACKGROUND Ibutilide is a class III antiarrhythmic drug, frequently used for conversion of atrial fibrillation and flutter. Retrospective cohort evaluations found that intravenous application of magnesium enhances the efficacy of ibutilide for chemical conversion of these arrhythmias. This prospective study sought to investigate the effects of intravenously pre-injected magnesium on the conversion rate of ibutilide for typical and atypical atrial flutter. METHODS We performed a prospective, randomized, placebo-controlled study. Patients with typical atrial flutter (TAF) or atypical atrial flutter (AAF) were randomized to receive either 4 g of intravenous magnesium sulfate or placebo immediately before administration of a maximum dose of 2 mg of ibutilide fumarate. Continuous rhythm monitoring for 4 h provided information on conversion to sinus rhythm. QT interval durations were measured before randomization, after magnesium, as well as 30 min and 4 h after starting ibutilide infusion. RESULTS We randomized 117 patients (58 with and 59 without pre-injection of magnesium; 65 with TAF and 52 with AAF). In patients with TAF, pre-injection of magnesium significantly improved the efficacy of ibutilide for conversion (85% with magnesium vs. 59% with placebo, p=0.017). In patients with AAF, no significant difference in conversion rates between patients receiving magnesium or placebo was detected (48% vs. 56%, p=0.189). Pre-injection of magnesium did not significantly influence the QT intervals at any time after administration of ibutilide. CONCLUSIONS Pre-injection of magnesium significantly enhances the efficacy of ibutilide for the conversion of TAF but not of AAF.

Removal of a chronically implanted active-fixation coronary sinus pacing lead using the Cook Evolution(C) lead extraction sheath.

In this case, a unipolar active-fixation coronary sinus lead (Star Fix®) had to be removed because of severe infection. For lead removal, a venous lead entry site approach with a transvenous mechanical dilator technique was …

Incidence of stent thrombosis in patients with drug eluting stents and short-term dual antiplatelet therapy

AIMS This study sought to investigate the incidence of stent thrombosis (ST) in patients treated with drug-eluting stents (DES) and clearly defined short-term dual antiplatelet therapy (DAT) for three or six months for sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES), respectively. METHODS AND RESULTS A series of 1023 consecutive patients with 1,414 stented lesions and prescribed short-term DAT were followed for at least two years after DES implantation. The individual durations of DAT, the rate of ischaemic events, and survival status were assessed. Follow-up was completed for 1017 patients (99.4%) with a mean follow-up of 3.0 +/- 0.7 years. DAT duration was 2.8 +/- 0.4 and 5.9 +/- 0.8 months in patients with SES and PES, respectively. Adherence to continued single antiplatelet therapy was 98.4%. We identified 14 patients with definite ST (1.4%) and no patients with probable ST with a cumulative incidence of 0.6% at 30 days, of 0.8% at one year, of 1.2% at 2 years, and of 1.4% at three years. CONCLUSIONS Definite or probable ST after DES implantation and short DAT occurs with a cumulative incidence of 1.4% at 3 years if excellent patient adherence to the continued single antiplatelet therapy can be achieved.

Ablation of a right-sided accessory pathway with the Hansen robotic system.

We report the case of a successful ablation of an accessory pathway (AP) with the Hansen robotic system. We used the robotic system for ablation of a right-sided AP, after no stable catheter position could be achieved with a handheld steerable sheath.

Clinical experience with routine use of a single combined mapping and ablation catheter for isolation of pulmonary veins in patients with paroxysmal atrial fibrillation.

ZusammenfassungHINTERGRUND: Die Pulmonalvenenisolation (PVI) mittels Katheterablation hat sich zur etablierten Therapie bei Patienten mit paroxysmalem Vorhofflimmern (PVF) entwickelt. Es war unser Ziel, die aufwendige interventionelle Prozedur der PVI durch die alleinige Verwendung eines neuen multipolaren Mapping- und Ablationskatheters bei geeigneten Patienten zu vereinfachen. METHODEN: Bei 64 Patienten mit PVF wurde vor der Durchführung einer PVI die anatomische Eignung zur vereinfachten Katheterablation mit dem High Density Mesh Ablator Catheter (MESH) mittels kardialer Computertomographie evaluiert. Eine PVI mittels MESH wurde schließlich bei 38 Patienten, welche die Voraussetzung von 4 unabhängig voneinander mündenden Pulmonalvenen mit einem ostialen Durchmesser von 15 – 25 mm erfüllten, durchgeführt. Die restlichen 26 Patienten dienten als Kontrollgruppe und wurden mit einem konventionellen Ablationskatheter unter zusätzlicher Verwendung eines zirkulären Mapping-Katheters und eines 3D-Mapping Systems abladiert. ERGEBNIS: Bei allen 38 Patienten konnte mit dem MESH in allen 4 Pulmonalvenen ein Mapping durchgeführt werden. Eine PVI wurde bei 142/148 (96 %) der Pulmonalvenen mit nachgewiesenen Potentialen erzielt. In der Kontrollgruppe konnten 100/105 (95 %) der Pulmonalvenen mit nachgewiesenen Potentialen isoliert werden. Die klinischen Ergebnisse nach 6 Monaten wiesen zwischen den beiden Gruppen keine signifikanten Unterschiede auf. SCHLUSSFOLGERUNG: Bei geeigneten Patienten kann mit dem routinemäßigen Einsatz des MESH bei reduzierter Komplexität der Prozedur eine PVI mit hoher akuter Erfolgsrate durchgeführt werden. Ob sich diese vereinfachte Ablationstechnik durchsetzen wird, hängt jedoch von den klinischen Ergebnissen einer Langzeit-Nachsorge ab.SummaryBACKGROUND: Catheter-based isolation of pulmonary veins has become established treatment for patients with paroxysmal atrial fibrillation. We wished to simplify the interventional procedure by using a single novel multipolar catheter for mapping and ablation in appropriate patients. METHODS: Sixty-four patients with paroxysmal atrial fibrillation scheduled for pulmonary vein isolation were screened by cardiac computed tomography for anatomic suitability to undergo a simplified procedure with the high-density mesh ablator catheter (MESH) as the only left atrial device. The procedure was undertaken in 38 patients matching the criteria of four clearly separated pulmonary veins with ostial diameters 15–25 mm; the remaining 26 patients served as a control group and were treated using a three-dimensional mapping system guided ablation using a circular mapping catheter and a single-point ablation catheter. RESULTS: In all 38 patients, all four pulmonary veins could be accessed and mapped with the MESH. Using the MESH, electrical isolation was achieved in 142/148 (96%) pulmonary veins with recorded potentials. In the control group, 100/105 (95%) pulmonary veins with recorded potentials could be isolated. After 6 months, clinical results did not differ significantly between the two treatment groups. CONCLUSION: In appropriate patients, the routine single catheter approach with the MESH for mapping and ablation yields a high acute success rate despite the reduced complexity of the procedure. Long-term data on clinical success rates are needed to justify this simplified approach.