[Long-term outcome of catheter ablation therapy of supraventricular tachyarrhythmias]

AIM

The aim of the article is presentation of our results and experiences with radiofrequency catheter ablation (CA) in the therapy of supraventricular tachyarrhythmias.

PATIENTS AND METHODS

From 1996 to 2009, 1 485 patients underwent CA (total procedure number - 1 627). The group consist of 772 patients with paroxysmal atrioventricular nodal reentry tachycardia (AVNRT): 484 women, mean age 50.3 +/- 16.4 years; 312 patients with atrioventricular reentry tachycardia (AVRT): 145 women, mean age 40.1 +/- 14.9 years; 391 patients with typical atrial flutter (AF): 96 women, mean age 61.6 +/- 11 years; and 64 patients with atrial tachycardia (AT): 35 women, mean age 53.6 +/- 14.2 years, focal AT 33, macroreentrant AT 31. CA was performed for more than one type of arrhythmia in 54 patients.

RESULTS

Acute ablation success was achieved in 98.7% of patients with AVNRT, 94.6% of patients with AVRT, 97.7% of patients with AF, and 81.3% of patients with AT. Serious procedure complications occurred in 22 patients (1.4%). The recurrence rate was 1.8-12.5%. 88 patients underwent successful reablation procedure. Long-term ablation success was achieved in 89-99% of patients depending on the different type of arrhythmia. During the long-term follow-up (mean 73 +/- 38 months) died 23 patients, the most common cause of death was malignancy (9 patients).

CONCLUSION

Our long-term experience and good results documented high success rate and safety of radiofrequency catheter ablation in the therapy of patients with supraventricular tachyarrhythmias.

[Improvement of quality of life after ablation of longstanding persistent versus paroxysmal atrial fibrillation: results of 2-year follow-up]

AIMS

The purpose of the study was to assess quality of life and socio-economic parameters in patients after ablation of paroxysmal versus longstanding persistent atrial fibrillation (AF).

METHODS

The study included 89 patients with paroxysmal AF and 56 patients with longstanding persistent AF who underwent ablation within 1 year, and were afterwards prospectively followed up for 2 years. Quality of life was evaluated by the EQ-5D questionnaire before and every 6 months after ablation.

RESULTS

Objective, respectively subjective quality of life at baseline was lower in patients with longstanding persistent AF (67 +/- 16 vs 71 +/- 10; p = 0.01, resp. 64 +/- 12 vs 67 +/- 16; p = 0.07); however, after 2 years, it exceeded that of the patients with paroxysmal AF (80 +/- 17 vs 75 +/- 18; p = 0.03; resp. 73 +/- 13 vs 70 +/- 17; p = 0.18). The baseline-2 year difference in improvement was higher in patients with longstanding persistent AF in both objective (p = 0.001) and subjective component (p = 0.05). Both groups displayed significant decrease in the days of hospitalization, and the days of working incapacity.

CONCLUSION

Patients with longstanding persistent AF exhibit worse baseline quality of life than the patients with paroxysmal AF, and higher quality of life improvement after ablation.

Hemostatic changes before and during electrophysiologic study and radiofrequency catheter ablation

We sought to investigate specific hemostasis activation markers during electrophysiologic study (EPS) with consequent radiofrequency catheter ablation (RFA). Sixty patients were studied prospectively during routine EPS with RFA for paroxysmal supraventricular tachycardia. Blood samples were drawn before the insertion of venous sheaths (T0), at the end of EPS (T1), and 30 min after completion of RFA (T2). To study coagulation and fibrinolytic and platelet activity, we measured concentrations of thrombin-antithrombin III (TAT), D-dimers (DD), plasminogen activator inhibitor type 1 (PAI-1), tissue-type plasminogen activator (t-PA), and circulating platelet aggregates. The results are expressed as median and show 95% confidence levels. Levels of DD increased from 0.24 mg/L at T0 to 0.37 mg/L at T1 (P < 0.001) and to 0.59 mg/L at T2 (P < 0.001). TAT levels increased from 5.29 μg/L at T0 to 35.80 μg/L at T1 (P < 0.001) and decreased to 26.30 μg/L at T2 (P < 0.001). PAI-1 concentration decreased from 30.10 μg/L at T0 to 26.4 μg/L at T1 (P < 0.001). t-PA at T2 increased to 5.10 μg/L from 4.75 μg/L at T1 (P = 0.001). No other differences between corresponding medians were statistically significant (P > 0.05). We found that concentrations of DD at T2 versus T1 depended on the number of radiofrequency energy applications (r (S) = 0.387; P = 0.002). Marked platelet activation was observed from the start of the procedure, without changes during the procedure.

High-sensitivity troponin T as a marker of myocardial injury after radiofrequency catheter ablation

Background

The aim of our study was to monitor radiofrequency catheter ablation-induced myocardial damage by measuring high-sensitivity cardiac troponin T (hs-cTnT).

Methods

Serum concentrations of hs-cTnT (Elecsys 2010 system, Roche) were measured in 73 healthy blood donors and serially in 27 patients who had samples taken both before and 24 h after radiofrequency ablation (RFA) for atrioventricular nodal re-entry tachycardia (AVNRT), atrial fibrillation (AF) or right atrial flutter (AFL).

Results

Significant increases of hs-cTnT were seen in patients after RFA (AVNRT: P = 0.0115, AF: P = 0.0011, AFL: P = 0.0009). Postprocedural serum hs-cTnT correlated with the number of radiofrequency applications and with the duration of RFA procedure. Spearman's coefficient of rank correlation ( r) were as follows: hs-cTnT versus RFA duration: r = 0.771 ( P < 0.001); hs-cTnT versus number of pulses: r = 0.708 ( P < 0.001). Patients with the diagnosis of AVNRT had lower serum hs-cTnT concentration after RFA compared with AFL ( P < 0.0001) and AF ( P < 0.0001) patients.

Conclusions

Our data indicate that RFA causes a significant increase of serum hs-cTnT concentration that could be used to monitor myocardial injury.

[Can we cure atrial flutter with radiofrequency ablation in an hour?]

BACKGROUND

Radiofrequency ablation of common atrial flutter requires the creation of a complete transmural ablation line across cavotricuspid region to achieve bidirectional conduction block. Irrigated tip catheters facilitate rapid achievement of this block by creation larger and deeper lesions. The EASTHER registry was organized to collect data about the efficacy of the procedure in small and middle volume centres in Central and Eastern Europe, all using THERMOCOOL catheter technology.

METHODS

Easther is a prospective registry (April 2002-February 2003). 133 consecutive patients (81.1% male, age 59.0 +/- 10.4 years, range 30-81 years) with common atrial flutter were enrolled. Coincidence with atypical flutter was observed in 2.7%. Patients had a history of flutter of 31.0 +/- 53.6 month (range 1-403) and concomitant atrial fibrillation was observed in 42.9%. Structural heart disease was present in 38.9%. Amount of re-ablated cases was 14%. RF energy was applied during 60 sec in power-controlled mode at a setting between 40 to 50 W with an average flow rate of 19.0 ml/min.

RESULTS

Acute success rate defined as bi-directional block was achieved in 93.1%, although 94.7% of cases were assessed successful by the treating electrophysiologist. Average number of RF applications was 12.0 +/- 7.0 (range 2-40) per procedure. Average delivered power varied between a minimum of 36.1 +/- 15.1 W till a maximum of 45.3 +/- 13.0 W, while the average maximum temperature observed at the same time was varied between 39.0 +/- 3.4 degrees C and 45.4 +/- 4.0 degrees C. Total procedure time was 100.1 +/- 42.7 min (range 20-280 min) and fluoroscopy time was 15.8 +/- 9.6 min (range 4-45 min). In comparable French TC registry Average total and fluoroscopy time were 46.4 +/- 33.6 min, and 10.0 +/- 6.8 min resp. In the Middle European centres total and fluoroscopy time was 96.1 +/- 40.9 min, and 15.0 +/- 8.9 min resp. In centres from Eastern Europe it was 120.3 +/- 51.2 min, and 20.4 +/- 11.9 min resp. Two adverse events were reported. Both patients had strong chest pain during ablation. These results are comparable with the literature data published.

CONCLUSIONS

Irrigated tip catheters are effective and safe in ablation of common atrial flutter. This technology helps to accelerate and facilitate achievement of bi-directional isthmus block. Most of procedures were terminated to one hour in experienced centers in France as early as 2002. Procedures not exceeding one hour are feasible in case of spreading this method as method of first choice with gaining of experiences in centres of Middle and Eastern Europe.

[The activation of haemostasis during radiofrequency catheter ablation]

The aim of the study was to investigate chosen haemostasis activation markers during electrophysiologic study (EPS) with consequent radiofrequency catheter ablation (RFA). Sixty-three patients were studied prospectively. Indications for EPS and RFA were supraventricular tachycardias with the arrhythmogenic substrate located in the right atrium. Blood samples were drawn 24 hours before the procedure (T -1), at the beginning of the procedure (T0), at the end of EPS (T1), 30 minutes after completion of RFA (T2), and 24 hours after the procedure (T3). To study coagulation, fibrinolytic and platelet activation were measured concentrations of thrombin-antithrombin III (TAT), D-dimers (DD), platelet count and parameters, and circulating platelet aggregates (CPAi). During the EPS and RFA, TAT levels increased from the baseline 5.03 +/- 2.53 microg/l (T -1) to 12.90 +/- 12.83 microg/l at T0 (p < 0.001) to 36.07 +/- 15.59 microg/l at T1 (p < 0.001) and decreased to 28.85 +/- 13.14 microg/l at T2 (p < 0.001). Levels of DD increased from 0.30 +/- 0.20 mg/l at T0 to 0.44 +/- 0.25 mg/l at T1 (p < 0.001) and to 0.87 +/- 0.74 mg/l at T2 (p < 0.001). The number of platelets was significantly decreased (-13.7%) before and during the procedure (T -1 vs. T3; p < 0.001). Marked platelet activation (CPAi 0.62 +/- 0.32) was observed before the procedure opposite to the physiological values (CPAi 1.0 +/- 0.1), without changes during the procedure (CPAi at T2 0.69 +/- 0.23). Our results confirmed activation of several haemostasis parameters during EPS and RFA, and support eligibility of the antithrombotic prevention in patients indicated for EPS and RFA.

[Syncope in ventricular tachycardia as a first clinical sign of patent ductus arteriosus in an adulthood]

The case-report describes a 48-year-old-female patient with the patent ductus arteriosus with the following structural changes leading to the malignant arrhythmias manifested as a syncope. The patient was treated by Amplatzer occluder and the implantation of the cardioverter-defibrillator. The authors discuss the patent ductus arteriosus, arrhythmias and sudden cardiac death in the patients with the congenital heart disease in an adulthood.

[Ventricular fibrillation in chronic heart disease]

The objective of the work was to describe in subjects with spontaneous ventricular fibrillation, after elimination of acute cardiac disease, the strategy of antiarrhythmic treatment and to evaluate, based on prospective follow-up, the effectiveness of this treatment. The authors included in the group 36 patients (30 men and 6 women) within the range from 34 to 78 years (mean age 58 +/- 11 years) with spontaneous ventricular fibrillation. They divided the group into a subgroup (15 subjects) without revascularization of the heart muscle, into a subgroup (17 subjects) with revascularization of the myocardium (coronary angioplasty and bypasses) and a subgroup (4 subjects) where ischaemic heart disease was ruled out (mostly cardiomyopathies). In all subgroups they used programmed ventricular stimulation (apparatuses of Quinton Co. USA, Biotronik Co. GFR), in the subgroup with revascularization within 3 months. During the diagnostic procedure of ventricular stimulation they tested antiarrhythmic drugs most frequently amiodarone per os (for 4 weeks). An implantable cardioverter--defibrillator was implanted in 17 patients (8 subjects without revascularization, 6 subjects with revascularization, 3 subjects without ischaemic heart disease). All patients were followed up till death, maximum 24 months. The authors evaluated the rate of cardiac deaths (death on cardiac grounds, incl. sudden arrhythmic death) and sudden arrhythmic deaths (within one hour after the onset of symptoms or the first malignant ventricular tachyarrhythmia recorded after implantation of the defibrillator). In the subgroup without revascularization with electric instability of the ventricles according to programmed stimulation 66.7% they described seven cardiac deaths (46.7%) and 6 sudden "arrhythmic" deaths (40%) incl. 5 subjects with ineffective testing of antiarrhythmic drugs. Conversely in the subgroup with revascularization and with diagnostic programmed stimulation in 47.1% they found 3 cardiac deaths (17.7%), one sudden "arrhythmic" death (5.9%)--a subject with ineffective testing. In the subgroup without ischaemic heart disease they recorded cardiac and sudden "arrhythmic" deaths in half the subjects, in all instances in subjects without inducible ventricular tachyarrhythmia. The authors found in the course of a two-year investigation a relapse of cardiac arrest in 25% of subjects after spontaneous ventricular fibrillation. A third of these subjects (all without a cardioverter-defibrillator) died. They confirm the benefit of implantation of a defibrillator for all subjects regardless of the basic diagnosis and revascularization of the heart muscle.

[Myocardial revascularization in malignant ventricular tachyarrhythmia--prognostic significance]

BACKGROUND

The survival of patients with chronic ischaemic heart disease and malignant ventricular tachyarrhythmia is influenced positively in some instances by revascularization of the heart muscle and implantation of a cardioverter-defibrillator. The objective of the submitted work was to evaluate by perspective follow-up of subjects with chronic ischaemic heart disease and malignant ventricular tachyarrhythmia: a) the effect of revascularization of the heart muscle on the prognosis, making use of programmed stimulation of the ventricles and testing the effectiveness of antiarrhythmic treatment; b) the importance of implantation of a cardioverter-defibrillator in revascularized and non-revascularized subjects for the prevention of sudden "arrhythmic" deaths.

METHODS AND RESULTS

The authors examined 37 patients (32 men and 5 women), age bracket 34 to 78 years (mean age 61 +/- 11) with IHD and spontaneous ventricular tachyarrhythmia after ruling out acute myocardial infarction. The group was divided into sub-groups without revascularization (21 subjects) and with revascularization (16 subjects). In both sub-groups programmed stimulation of the ventricles was implemented. During the diagnostic finding of programmed stimulation they tested antiarrhythmic drugs, most frequently amiodarone administered orally. A cardioverter-defibrillator was implanted to 10 patients. All patients were followed-up to death, the longest period being 24 months. They evaluated the frequency of cardiac deaths (death on cardiac grounds incl. sudden "arrhythmic" death) and sudden "arrhythmic" deaths (death within on hour after onset of symptoms or first recorded malignant ventricular tachyarrhythmia). In the sub-group without revascularization with diagnostic inducibility of the heart muscle in 85.7% of patients the authors described 9 cardiac deaths (42.9%) and 8 sden "arrhythmic" deaths (38.1%). Conversely in the sub-group with revascularization and with diagnostic programmed stimulation of the ventricles in half the subjects 5 clinical deaths were found (31.3%) and 3 sudden "arrhythmic" deaths (18.8%). Analysis of 11 sudden "arrhythmic" deaths revealed that no subjects with an implanted cardioverter-defibrillator (5) died (documented malignant ventricular tachyarrhythmia). Five of the six patients who died (all without a cardioverter-defibrillator) were not revascularized.

CONCLUSIONS

Revascularization of the heart muscle in patients with ischaemic heart disease (after elimination of acute cardiac infarction) and malignant ventricular tachyarrhythmia reduces the risk of relapse of this arrhythmia. The benefit of implantation of a cardioverter-defibrillator was recorded in all subjects regardless of the revascularization of the heart muscle.

[Revascularization of the myocardium and electrical instability of the ventricles]

The objective of the investigation was to evaluate in patients with chronic ischaemic heart disease (IHD) and malignant ventricular tachyarrhythmia the asset of myocardial revascularization for improvemet of the electric instability of the ventricular myocardium and a subsequent outline of the tactics of antiarrhythmic treatment. The authors included in the group a total of 35 patients (30 men and 5 women), age 34-78 years (mean 61 +/- 11) with IHD (according to selective coronarography) with spontaneous ventricular fibrillation (18 sebjects) or persistent (above 30s) marked symptomatic ventricular tachycardia (17 subjects), after ruling out acute cardiac infarction. The group was divided into a subgroups of 16 subjects with revascularization of the heart muscle (coronary angioplasty, coronary bypass) and a subgroup (19 subjects) without revascularization of the hearth muscle. In both groups programmed stimulation of the cardiac chambers was implemented (PSSK) (apparatuses of Qinton Co. USA, Biotronik, GFR), in the subgroup after revascularization within three months. In case of a PSSK finding the authors tested antiarrhythmic drugs, most frequently amiodarone by the oral route (within one month). Treatment not causing permanent ventricular arrhythmia was considered effective. In the subgroup with revascularization the authors described diagnostic PSSK in 8 subject where testing of antiarrhythmics was made in 6 patients (an effective antiarrhythymic agent was found in one instance, i.e. in 16.7%). In the subgroup without revascularization diagnostic PSSK was implemented in 17 subject. Antiarrythmic drugs were tested in 16 patients (effective treatment in 12.5%--always amiodaroe by the oral route). Diagnostic ventricular tachyarrhythmia was found in patients with spontaneous ventricular tachycardia in all instances with revascularization and in 92.3% without revascularization. In patients with spontaneous ventricular fibrillation they proved diagnostic PSSK in 33.3% of the patients with revascularization and in 66.7% without revascularization. The relative number of implantation of cardioverter-defibrillators in group with and without revascularization was similar (25%, 26.3%). Revascularization of the heart muscle in patients with chronic IHD reduces markedly the electric instability of the ventricular heart muscle, in particular in case of spontaneou ventricular fibrillation. Selective coronarography and possibly revascularization of the heart muscle is esential in those patients. The tactics of antiarrhythymic treatment of revascularization of the heart muscle were not affected.