Lilian Mantziari

The impact of recently introduced asymmetric bidirectional ablation catheters on procedural parameters and acute success rates of ablation procedures is unknown. We retrospectively analyzed data regarding ablations using a novel bidirectional catheter in a tertiary cardiac center and compared these in 1:5 ratio with a control group of procedures matched for age, gender, operator, and ablation type. A total of 50 cases and 250 controls of median age 60 (50-68) years were studied. Structural heart disease was equally prevalent in both groups (39%) while history of previous ablations was more common in the study arm (54% vs 30%, P = 0.001). Most of the ablation cases were for atrial fibrillation (46%), followed by atrial tachycardia (28%), supraventricular tachycardia (12%), and ventricular tachycardia (14%). Median procedure duration was 128 (52-147) minutes with the bidirectional, versus 143 (105-200) minutes with the conventional catheter (P = 0.232), and median fluoroscopy time was 17 (10-34) minutes versus 23 (12-39) minutes, respectively (P = 0.988). There was a trend toward a lower procedure duration for the atrial tachycardia ablations, 89 (52-147) minutes versus 130 (100-210) minutes, P = 0.064. The procedure was successfully completed in 96% of the bidirectional versus 84% of the control cases (P = 0.151). A negative correlation was observed between the relative fluoroscopy duration and the case number (r = -0.312, P = 0.028), reflecting the learning curve for the bidirectional catheter. The introduction of the bidirectional catheter resulted in no prolongation of procedure parameters and similar success rates, while there was a trend toward a lower procedure duration for atrial tachycardia ablations.

The aim of the present study was to examine the value of the right atrial volume index (RAVI) as predictor of functional capacity in patients with heart failure. A total of 51 patients with stable chronic heart failure of ischaemic or non-ischaemic aetiology were prospectively enrolled. The systolic function of the right ventricle was quantified using the tricuspid annular plane systolic excursion (TAPSE). Right atrial volume was measured in the apical 4-chamber view and was indexed to body surface area. The functional capacity was assessed by the Duke Activity Status Index (DASI). Patients with a low functional capacity (DASI<10) had lower TAPSE (1.4 ± 0.3 cm versus 2.0 ± 0.4 cm, p<0.001), higher RAVI (42 ± 15 ml/m(2) versus 22 ± 9 ml/m(2), p<0.001), higher estimated right ventricular systolic pressure (61 ± 13 mmHg versus 40 ± 16 mmHg, p<0.001), larger right ventricular end-diastolic diameter (4.7 ± 0.8 cm versus 3.6 ± 0.7 cm, p<0.001) and lower left ventricular ejection fraction (26 ± 6% versus 30 ± 7%, p=0.022). Multivariate analysis revealed that TAPSE was the single independent predictor of DASI. In the subgroup of patients with reduced right ventricular systolic function (TAPSE<2 cm), RAVI was the single independent predictor of low DASI. In the overall population RAVI=30.6 ml/m(2) had 75% sensitivity and 83% specificity in predicting DASI<10. Within the subgroup of patients with TAPSE<2 cm, RAVI=30.6 ml/m(2) had better sensitivity and specificity (79% and 90% respectively) in predicting DASI<10. Increased right atrial volume index predicts low functional capacity quantified by the Duke Activity Status Index in patients with stable chronic heart failure.

We explored the differences in epidemiologic, clinical, laboratory and echocardiographic characteristics between idiopathic dilated (IDCM) and ischaemic cardiomyopathy (ICM). Consecutive patients with stable chronic heart failure evaluated at a tertiary cardiac centre were enrolled. Clinical examination, blood tests and echocardiographic study were performed. A total of 76 patients (43 IDCM, 33 ICM) were studied. IDCM patients were younger (p<0.001) and female gender was more prevalent (p=0.022). NYHA class and left ventricular ejection fraction were similar. IDCM patients had lower rates of dyslipidaemia (p<0.001) but smoked more than ICM patients (p=0.023) and had higher rates of family history of sudden cardiac death (p=0.048). Blood pressure was similar but resting heart rate was higher in IDCM patients (p=0.022). IDCM patients presented less frequently with peripheral oedema or ascites (p=0.046 and 0.020, respectively) and showed better right ventricular function on echocardiogram. QRS duration was similar between groups but only in IDCM patients there was a positive correlation between QRS duration and age (r=0.619, p<0.001). Cardiac output was similar but functional capacity assessed by the Duke Activity Status Index was better in IDCM (p=0.036). Despite these differences, IDCM and ICM patients received similar treatments. Patients with IDCM were younger, presented lower rates of right ventricular dysfunction and clinical right ventricular failure and had better functional capacity. Additional differences in clinical and laboratory findings exist pointing to a different patient population with diverse prognosis and potential need for individualized management.

In 2008 the radiofrequency ablation procedures (RFA) registry of the Hellenic Cardiological Society (HCS) was created. This is a dynamic, web-based application, which acts as the interface for storing and retrieving patients' demographic data and ablation procedures. Access to the site is permitted only to registered users. The purpose of this study is to report the results of RFA procedures performed in Greece over the 2008-2010 period. There are 27 centers in 24 hospitals that are licensed to perform RFA in Greece. During the period 2008-2010, 3541 RFA procedures were performed in 3344 patients in 23 centers. Four centers did not contribute data at all for various reasons. It is interesting that nearly 50% of the total number of procedures were performed at 3 high volume centers (>100 cases/year). The most common procedure was slow pathway ablation for atrioventricular reentrant tachycardia, the second was ablation of accessory pathway related tachycardias, and the third was ablation of atrial fibrillation. Success rates were high (92.1%), the complication rate was 3% (serious complications <1%) and total relapse rate was 8.7% at six months' follow up. The electronic RFA registry in Greece confirmed that all RFA procedures are performed in Greece with high success and low complication rates, comparable to the European and US standards. The experience and results from the first three-year period using the registry are very interesting and encouraging, thus indicating the need for development of similar databases at the national level.