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Aims Cerebral embolism is a possible serious complication during catheter ablation of atrial fibrillation (AF). The purpose of this prospective pilot study was to analyse the incidence and possible impact of cryo ablation on cerebral lesions and possible differences to radiofrequency (RF) ablation during pulmonary vein isolation (PVI). Methods and results Pulmonary vein isolation was performed in 89 patients, either with the cryoballoon technique (n = 45) or with RF ablation (n = 44). Phenprocoumon was stopped 3 days before intervention and replaced by subcutaneous low-molecular-weight heparin. During the catheter procedure, an infusion of unfractionated heparin was maintained to achieve an activated clotting time (ACT) of >300 s. Cerebral magnetic resonance imaging scans were performed 1 day before and after PVI, and at 3-month follow-up. Chronic lesions were observed in 11 patients (12.3%) before PVI without statistically significant difference between the two groups. None of the patients had neurological symptoms during or following the procedure. Seven patients (7.9%) developed acute lesions 1 day after PVI, without statistically significant difference between the group treated by cryoenergy (8.9%) and RF ablation (6.8%). Patients with acute lesions were significantly older compared with those without acute cerebral lesions. No additional cerebral lesions during follow-up were observed. Conclusion A considerable portion of patients with AF but without any neurological symptoms had chronic cerebral lesions before PVI. Additional acute lesions could be added after the procedure. Both ablation techniques showed additional cerebral acute lesions with no neurological symptoms after PVI. [ABSTRACT FROM PUBLISHER]

Introduction: Severe pulmonary vein stenosis (PVS) after catheter ablation of atrial fibrillation (AF) is a well-recognized complication with a further reported incidence of 1.3%. The preferred therapy for symptomatic PVS is pulmonary vein (PV) angioplasty, but this treatment modality is followed by restenosis in 44–70%. Whether there is additional long-term benefit from PVS stenting is uncertain. The aim of this study was the evaluation of the long-term success after PV stenting of severe stenosis. Methods and Results: Ten patients (pts) with 13 PVS were prospectively evaluated. PV stenting was performed with Palmaz Genesis stents. Magnetic resonance imaging (MRI), lung perfusion scans, and CT-scans were performed before, directly after, and every 12 months thereafter. Primary endpoint of the study was the occurrence of restenosis after PV stenting. After a median follow-up of 47.7 (IQRs 25/75 47.2–48.5) months, the primary endpoint was achieved in 3 out of 13 PVs (23% of the treated PVs). We observed two in-stent restenosis 2 and 4 years after PV stenting. These pts experienced onset of dyspnea some weeks before. After an additional balloon angioplasty, the in-stent restenosis was resolved. In one asymptomatic patient, we observed an occlusion of the PV stent 13 months poststenting. Normalization of lung perfusion was noted 4 years after PV stenting versus directly poststenting in all pts without in-stent restenosis (n = 7). Conclusion: PVS stenting with stent sizes ≥10 mm seems to be an adequate therapy modality for treatment of severe acquired PVS. Late in-stent restenosis after PVS stenting can occur. The normalization of the initially disturbed lung perfusion scan is possible and remains stable, even 4 years after PVS stenting. [ABSTRACT FROM AUTHOR]

Multi-detector CT reliably permits visualization of coronary arteries, but due to the occurrence of motion artefacts at heart rates >65 bpm caused by a temporal resolution of 165 ms, its utilisation has so far been limited to patients with a preferably low heart rate. We investigated the assessment of image quality on computed tomography of coronary arteries in a large series of patients without additional heart rate control using dual-source computed tomography (DSCT). DSCT (Siemens Somatom Definition, 83-ms temporal resolution) was performed in 165 consecutive patients (mean age 64 +/- 11.4 years) after injection of 60-80 ml of contrast. Data sets were reconstructed in 5% intervals of the cardiac cycle and evaluated by two readers in consensus concerning evaluability of the coronary arteries and presence of motion and beam-hardening artefacts using the AHA 16-segment coronary model. Mean heart rate during CT was 65 +/- 10.5 bpm; visualisation without artefacts was possible in 98.7% of 2,541 coronary segments. Only two segments were considered unevaluable due to cardiac motion; 30 segments were unassessable due to poor signal-to-noise ratio or coronary calcifications (both n = 15). Data reconstruction at 65-70% of the cardiac cycle provided for the best image quality. For heart rates >85 bpm, a systolic reconstruction at 45% revealed satisfactory results. Compared with earlier CT generations, DSCT provides for non-invasive coronary angiography with diagnostic image quality even at heart rates >65 bpm and thus may broaden the spectrum of patients that can be investigated non-invasively. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the radiation-dose-reduction potential of automatic exposure control (AEC) in 16-slice and 64-slice multislice computed tomography (MSCT) of the coronary arteries (computed tomography angiography, CTA) in patients. The rapid growth in MSCT CIA emphasises the necessity of adjusting technique factors to reduce radiation dose exposure. Design: A retrospective data analysis was performed for 154 patients who had undergone MSCT CTA. Group 1 (n = 56) had undergone 16-slice MSCT without AEC, and group 2 (n = 51), with AEC. In group 1, invasive coronary angiography (ICA) had been performed in addition. Group 3 (n = 47) had been examined using a 64-slice scanner (with AEC, without ECG-triggered tube current modulation). Results: In group 1, the mean (SD) effective dose (ED) for MSCT CIA was 9.76 (1 .84) mSv and for ICA it was 2.6 (1.27) mSv. In group 2, the mean ED for MSCT CIA was 5.83 (1.73) mSv, which signifies a 42.8% dose reduction for CTA by the use of AEC. In comparison to ICA, MSCT CIA without AEC shows a 3.8-fold increase in radiation dose, and the radiation dose of CTA with AEC was increased by a factor of 1 .9. In group 3, the mean ED for MSCT CIA was 1 3.58 (2.80) mSV. Conclusions: This is the first study to show the significant dose-reduction potential (42.8%) of AEC in MSCT CIA in patients. This relatively new technique can be used to optimise the radiation dose levels in MSCT CIA. [ABSTRACT FROM AUTHOR]

We present gadolinium-enhanced cardiac magnetic resonance imaging (CMRI) in Tako-Tsubo-like left ventricular dysfunction showing the findings in acute phase and in follow-up. Gadolinium-enhanced CMRI allows to distinguish between myocardial infarction and other myocardial alterations, e.g., myocarditis. CMRI may thus permit to non-invasively identify patients with Tako-Tsubo syndrome by ruling out myocardial infarction or myocarditis in the setting of wall motion abnormalities (WMA). [ABSTRACT FROM AUTHOR]