Myocardial scar extent evaluated by cardiac magnetic resonance imaging in ICD patients: relationship to spontaneous VT during long-term follow-up.

Patients with ischemic cardiomyopathy have an increased risk for ventricular arrhythmia, since myocardial infarction can be the substrate for re-entrant arrhythmias. Contrast-enhanced cardiac magnetic resonance imaging (CMR) has proven to reliably quantify myocardial infarction. Aim of our study was to evaluate correlations between functional and contrast-enhanced CMR findings and spontaneous ventricular tachy-arrhythmias in patients with ischemic cardiomyopathy who underwent implantable cardioverter-defibrillator (ICD) therapy. Forty-one patients with ischemic cardiomyopathy and indication for ICD therapy underwent cine and late gadolinium enhancement CMR for quantification of left ventricular volumes, function and scar tissue before subsequent implantation of ICD device. During a follow-up period of 1184 ± 442 days 68 monomorphic and 14 polymorphic types of ventricular tachycardia (VT) could be observed in 12 patients. Patients with monomorphic VT had larger scar volumes (25.3 ± 11.3 vs. 11.8 ± 7.5% of myocardial mass, P < 0.05) than patients with polymorphic VT. Moreover myocardial infarction involved more segments in the LAD perfusion territory (86 vs. 20%, P < 0.05) than in patients with polymorphic VT. Patients with spontaneous monomorphic VT during the long-term follow-up period had more infarcted tissue, which was more often present in the LAD perfusion territory than patients with polymorphic events. These data strengthen the diagnostic benefit of CMR in patients with ischemic cardiomyopathy. CMR may be used for better risk stratification in patients with ischemic cardiomyopathy undergoing ICD therapy.

Cryoablation versus radiofrequency energy for the ablation of atrioventricular nodal reentrant tachycardia (the CYRANO Study): results from a large multicenter prospective randomized trial.

BACKGROUND: Cryoablation has emerged as an alternative to radiofrequency catheter ablation (RFCA) for the treatment of atrioventricular (AV) nodal reentrant tachycardia (AVNRT). The purpose of this prospective randomized study was to test whether cryoablation is as effective as RFCA during both short-term and long-term follow-up with a lower risk of permanent AV block. METHODS AND RESULTS: A total of 509 patients underwent slow pathway cryoablation (n=251) or RFCA (n=258). The primary end point was immediate ablation failure, permanent AV block, and AVNRT recurrence during a 6-month follow-up. Secondary end points included procedural parameters, device functionality, and pain perception. Significantly more patients in the cryoablation group than the RFCA group reached the primary end point (12.6% versus 6.3%; P=0.018). Whereas immediate ablation success (96.8% versus 98.4%) and occurrence of permanent AV block (0% versus 0.4%) did not differ, AVNRT recurrence was significantly more frequent in the cryoablation group (9.4% versus 4.4%; P=0.029). In the cryoablation group, procedure duration was longer (138±54 versus 123±48 minutes; P=0.0012) and more device problems occurred (13 versus 2 patients; P=0.033). Pain perception was lower in the cryoablation group (P<0.001). CONCLUSIONS: Cryoablation for AVNRT is as effective as RFCA over the short term but is associated with a higher recurrence rate at the 6-month follow-up. The risk of permanent AV block does not differ significantly between cryoablation and RFCA. The potential benefits of cryoenergy relative to ablation safety and pain perception are counterbalanced by longer procedure times, more device problems, and a high recurrence rate. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00196222.

Angiographic results of a Tacrolimus-eluting stent in acute coronary syndrome lesions.

BACKGROUND: The Janus stent releases Tacrolimus from reservoirs located at the abluminal stent surface without any polymer. In stable coronary lesions the stent did not show relevant antiproliferative effects. Since Tacrolimus provides antiproliferative and antiinflammatory properties, we sought to investigate the efficacy of the Tacrolimus eluting Janus stent in acute coronary syndrome lesions with a more pronounced inflammatory cell reaction compared to stable coronary artery lesions. METHODS: Patients with acute coronary syndrome (STEMI or NSTEMI) undergoing cardiac catheterization and stent implantation were enrolled in this prospective registry. Primary outcome measure was in-stent late lumen loss at 6 months. There were two pre-specified subgroups based on presence or absence of high-pressure post-dilation (HPPD) with a balloon >or= 0.25 mm larger than the delivery balloon. RESULTS: Sixty patients were enrolled. In 34 patients HPPD was performed. Reference diameter was 2.85+/-0.57 mm. Stented length was 30.8+/-23.8 mm in HPPD and 19.7+/-7.3 mm in non-HPPD group. For the total population in-stent late loss was 0.92+/-0.80 mm and binary restenosis rate 32.6%. Late loss (1.09+/-0.74 mm Vs. 0.64+/-0.83 mm) and binary restenosis rate (37.0% Vs. 25.0%) were higher in the HPPD subgroup compared to lesions in non-HPPD. The angiographic evidence of thrombus was associated with a higher late loss. Restenotic pattern was occlusive in 40%, diffuse in 33% and focal in 27%. CONCLUSION: The use of the Tacrolimus eluting Janus stent in acute coronary syndrome lesions was associated with a high late lumen loss, a high angiographic restenosis rate and a mainly occlusive or diffuse pattern of restenosis.

Reproducibility of the proximal flow convergence method in mitral and tricuspid regurgitation.

BACKGROUND: The follow-up of patients with mitral and tricuspid regurgitation is important for their clinical treatment. We aimed to evaluate the reproducibility of the flow convergence method in mitral and tricuspid regurgitation. METHODS: The proximal flow convergence region was imaged with color Doppler ultrasound scanning echocardiography in 83 patients with mitral regurgitation, tricuspid regurgitation, or both. Proximal isovelocity surface area radii for aliasing velocities of 27 to 29 cm/s and 41 to 43 cm/s were repeatedly measured by the same experienced investigator on different days and by experienced and less experienced investigators at 1 day. RESULTS: In mitral regurgitation, the intraobserver variability rate was 0.2% +/- 13.5% (2.8% +/- 13.3%) and the interobserver variability was 0.1% +/- 13.8% (1.7% +/- 18.0%) for an aliasing velocity of 27 to 29 cm/s (41-43 cm/s). For the aliasing velocity of 27 to 29 cm/s (41-43 cm/s), the 95% ranges for change of the proximal isovelocity surface area radii were +/- 2.7 mm (+/- 1.8 mm) for measurements repeated by the same investigator and +/- 2.7 mm ( +/- 2.4 mm) for different investigators. Interobserver variability was independent of the investigators' experience. Similar data were achieved in tricuspid regurgitation. CONCLUSIONS: The proximal flow convergence method is acceptably reproducible in mitral and tricuspid regurgitation independent of the investigators experience. For the aliasing velocity of 27 to 29 cm/s (41-43 cm/s), the proximal isovelocity surface area radius has to change for >2.7 (2.4) mm before an altered severity of mitral or tricuspid regurgitation in a single patient can be assumed.

Quantification of mitral regurgitation by the proximal flow convergence method--comparison of transthoracic and transesophageal echocardiography.

BACKGROUND: No dataexist to indicate whether transthoracic (TTE) and transesophageal echocardiography (TEE) are of comparable value for the detection and quantification of mitral regurgitation using the proximal flow convergence method. HYPOTHESIS: The study was performed to compare the value of TTE and TEE for the detection and quantification of mitral regurgitation using this method. METHODS: The study included 57 patients with and 11 patients without mitral regurgitation. In all patients, the proximal flow convergence region was imaged by transthoracic and transesophageal color Doppler echocardiography, and proximal isovelocity surface area radii were determined. In 19 patients, monoplane TEE and in 49 patients multiplane TEE was performed. Thirty-one patients with mitral regurgitation underwent cardiac catheterization. RESULTS: Both methods had a comparable sensitivity for the detection of mitral regurgitation. Proximal isovelocity surface area radii derived from TTE and TEE agreed moderately (mean difference -0.5 +/- 1.3 mm). TTE and TEE correlated significantly with the angiographic grade (rank correlation coefficients 0.83 and 0.81), and both differentiated mild to moderate from severe mitral regurgitation with an accuracy of 90%. Regurgitant volumes derived from both echocardiographic techniques and cardiac catheterization correlated moderately (correlation coefficients between 0.67 and 0.81). CONCLUSIONS: TTE and TEE were of comparable value for the detection and quantification of mitral regurgitation using the proximal flow convergence method.