Cryoballoon ablation of atrial fibrillation in patients with advanced systolic heart failure and cardiac implantable electronic devices.

BACKGROUND: Pulmonary vein isolation with cryoballoon catheter ablation (CCB) is an effective method of treatment in patients with atrial fibrillation (AF), but in patients with heart failure (HF) the role of CCB remains unknown. AIM: The aim of the study was to assess the feasibility, effectiveness, and safety of CCB in patients with HF and cardiac im-plantable electronic devices (CIEDs), the impact of the procedure on symptoms, and echocardiographic parameters. METHODS: Thirty consecutive HF patients with left ventricular ejection fraction (LVEF) ≤ 40% and CIED, referred for CCB of AF, were included. Procedural parameters were compared to a group of 59 consecutive patients without cardiac diseases referred for CCB (control group). RESULTS: The number of veins ablated per patient was smaller and application was performed less frequently in the right inferior pulmonary vein in the HF group compared with the control group (66.7% vs. 88.1%; p = 0.01, respectively). In two (6.7%) patients from the HF group and in five (8.5%) from the control group procedure-related complications occurred (p = 0.76). After six months 21 HF patients (70%), after one year 13 (43%), and after 625 days only three (10%) were free from arrhythmia. AF burden was significantly reduced after six months compared to the pre-ablation period (18.5% vs. 52.9%; p = 0.001). New York Heart Association and European Heart Rhythm Association classes were both significantly (p < 0.001) reduced and LVEF was higher after six months in the HF patients. CONCLUSIONS: Safety and feasibility of CCB for AF in HF patients with CIED are comparable to subjects with structurally nor-mal heart; however, stable positioning of the balloon in the right inferior pulmonary vein may be more challenging. Although late recurrences are common, ablation reduces arrhythmia burden and leads to a long-term improvement of symptoms and echocardiographic indices.

Long-term outcome of catheter ablation and other form of therapy for electrical storm in patients with implantable cardioverter-defibrillators.

PURPOSE: Radiofrequency catheter ablation (RFCA) for electrical storm (ES) has become a widely used therapeutic method. Its effectiveness in comparison to other forms of ES treatment is however uncertain. METHODS: This single-centre retrospective study investigated the long-term clinical outcome after RFCA for ES and compared long-time effects of ablation to other forms of treatment. The study population consisted of 70 consecutive patients hospitalised between January 2010 and June 2015 due to ES. Patients were recruited for the study if the following criteria were fulfilled: first ES caused by ventricular tachycardia (VT) or ventricular fibrillation (VF), implanted cardioverter defibrillator or cardiac resynchronisation therapy device and left ventricular ejection fraction < 50%. The follow-up data on VT/ES recurrence was obtained from pacemaker/implanted cardioverter defibrillator memory. Data on all-cause mortality was collected during outpatient visits or by telephone contact. RESULTS: Of the 70 patients enrolled, 28 (40%) were treated with RFCA (group A) and 42 (60%) received other forms of treatment for ES (group B). During a mean (±SD) 864 (629) days of follow-up, death occurred in 4 (14.3%) patients in the ablation group and in 16 (38.1%) patients treated with other methods [p = 0.03]. There was no significant between-group difference in VT/VF and ES recurrence. Statistical analysis revealed that the presence of cardiac resynchronisation therapy device during ES, stroke and/or transient ischaemic attack and lower baseline hematocrit level were the multivariate predictors of all-cause mortality. CONCLUSIONS: In patients treated with RFCA for ES, all-cause mortality was significantly lower compared to the group treated with other methods.

Ferritin as a potential biomarker of efficacy of treatment of atrial fibrillation - preliminary report.

BACKGROUND: Complex mechanisms of responsible for originating and maintaining of atrial fibrillation (AF) are involved in pathophysiology of this arrhythmia. Inflammation substantially contribute to arrhythmic remodelling of atrial tissue.The aim of the present study is to assess an applicability of ferritin and high sensitive C-reactive protein (hs-CRP) as biomarkers of atrial fibrillation and their usefulness in evaluation of efficacy of cryoablation. MATERIALS AND METHODS: The study population consisted of 40 patients who underwent first AF cryoablation procedure. The whole follow-up time was for 6 months. The efficacy of cryoablation was defined as lack of episodes of AF longer than 30 s reported either in patient's medical documentation or present in standard or Holter ECG records. Concentrations of hs-CRP (latex method ) and ferritin (immunochemical method) were determined in standard way in hospital laboratory. RESULTS: The recurrence of atrial fibrillation during follow-up was detected in 7 of 40 patients (efficacy 82.5%). Basal concentrations of hs-CRP and ferritin were significantly higher in patients who underwent ablation during AF. Ablation resulted in an increase of either hs-CRP or ferritin concentrations. After seven days, both hs-CRP and ferritin concentrations returned to basal level. The trend toward the higher concentration of hs-CRP was observed in AF recurrence subgroup in 30th and the 90th day after the procedure. Ferritin concentrations were significantly higher in recurrence subgroup after 30 and 90 days. CONCLUSION: Our results suggest that the evaluation of ferritin serum level can be a potential tool for assessment of AF treatment efficacy.

Do we need to monitor the percentage of biventricular pacing day by day?

BACKGROUND: Incidence and clinical significance of transient, daily fluctuations of biventricular pacing percentage (CRT%) remain unknown. We assessed the value of daily remote monitoring in identifying prognostically critical burden of low CRT%. METHODS AND RESULTS: Prospective, single-centre registry encompassed 304 consecutive heart failure patients with cardiac resynchronization therapy defibrillators (CRT-D). Patients with 24-h episodes of CRT% loss<95% were assigned to quartiles depending on cumulative time spent in low CRT%: quartile 1 (1-8days), 2 (9-20days), 3 (21-60days) and quartile 4 (>60days). During median follow-up of 35months 51,826 transmissions were analysed, including 15,029 in 208 (68.4%) patients with episodes of low CRT%. Overall, mean CRT%≥95% vs. <95% resulted in a 4-fold lower mortality (17.3 vs. 68.2%; p<0.001). Fifty-four percent of patients experienced episodes of CRT% loss, despite 85.6% having mean CRT%≥95%. Mortality was lowest in quartile 1 (7.7%), while longer periods of CRT% loss resulted in significantly higher death rates (25.0 vs. 34.6 vs. 57.7%; quartiles 2-4 respectively, p<0.001), despite mean CRT% still being ≥95% in quartiles 1-3. Cumulative low CRT% burden was the independent risk factor for death (HR 1.013; 95% CI 1.006-1.021; p<0.001). Mortality rose by 1.3 and 49% with every additional day and quartile of CRT% loss, respectively. CONCLUSIONS: Daily remote monitoring allows one to detect 24-h episodes of CRT% loss<95% in over two-thirds of CRT-D recipients during median observation of 3years. Cumulative low CRT% burden (in days) independently predicts mortality before mean CRT% drop.

Day by day telemetric care of patients treated with cardiac resynchronisation therapy: first Polish experience.

BACKGROUND: Due to the recent rapid increase in the number of patients implanted with pacemakers, cardioverter-defibrillators (ICD), and cardiac resynchronisation therapy devices (CRT), conventional monitoring at specialist clinics is becoming increasingly difficult. The development of technology has enabled remote device monitoring with the use of teletransmission systems. AIM: To assess the effectiveness of transmission and the possibility of using telemetric data for further clinical management of patients with heart failure (HF) treated with CRT-D. METHODS: The analysis included 305 consecutive patients with chronic HF, New York Heart Association functional classes II-IV, treated with the use of CRT-D by Biotronik or Medtronic in the years 2006-2012. The patients received transmitters, enabling the remote monitoring of the implanted device from the patients' houses. Scheduled reports were automatically sent every month. The triggers for pre-specified emergency alert transmissions were as follows: ventricular tachycardia (VT) or ventricular fibrillation (VF) episodes, CRT-D intervention, ventricular extrasystoles > 110/h, any episode of atrial fibrillation (AF), atrial flutter (AFL) or supraventricular tachycardia, mean heart rate (HR) during, mean 24-h HR, CRT pacing < 95%, Elective Replacement Indicator, or End Of Service and device malfunction. The all-cause mortality of the study population has been assessed at the end of the follow-up period (mean of 20.5 months). RESULTS: Devices manufactured by Biotronik were provided to 71% of the study population, while 29% received devices by Medtronic. In 97.3% of cases, the monitors were wireless, fully automatic, and capable of immediate data transmission whenever a pre-specified alert notification was fulfilled. The analysis of long-term outcomes revealed that all-cause mortality of the whole study population was 13%. The effectiveness of report transmission was 98%. During follow-up a total of 31,198 transmissions were received and analysed, which constituted, on average, 4.9 transmissions per patient per month. Among analyses, 30% were reports generated by scheduled remote follow-ups, and 70% were caused by unscheduled device alerts. Correct functioning of the system was confirmed; the quality of the received data was 100%. In 63.9% of patients, decisions based on the information obtained from telemonitoring reports were made to modify the therapy, refer the patients to cardiology or electrophysiology clinics, or hospitalise them urgently. The most common medical reaction was device reprogramming (46.8%). Pharmacotherapy was modified in 33.7% of patients: beta-blocker dose increase (25.9%), anticoagulant treatment inclusion (15.7%), amiodarone inclusion (1.9%), or digoxin inclusion (4.5%). The remaining medical responses were referring patients for atrioventricular junction ablation (8.1%), VT ablation (2.9%), or AF/AFl ablation (1.6%). CONCLUSIONS: Remote monitoring of implantable devices is feasible, safe, and effective in supervising patients with CRT-D devices. Daily-based remote monitoring of a large population of HF patients allows continuous "triage" of high-risk patients and selection of individuals who require urgent intervention.

Quality of life in cardiac resynchronization recipients: association with response and impact on outcome.

BACKGROUND: The prognostic impact of improvement in health-related quality of life (QoL) and its relation to response in cardiac resynchronization therapy (CRT) recipients remains unknown. AIM: To assess the correspondence between response to CRT and improvements in QoL and to verify if a change in QoL after pacing influences outcome in CRT patients. METHODS: Ninety-seven participants of the Triple-Site Versus Standard Cardiac Resynchronization Therapy Trial (TRUST CRT) randomized trial, in New York Heart Association class III-IV, QRS width ≥ 120 ms, left ventricular ejection fraction ≤ 35%, and significant mechanical dyssynchrony were included. Subjects filled out the Minnesota-QoL questionnaire prior to and 6 months after CRT with defibrillator (CRT-D) implantation. Data on major adverse cardiac events (MACEs: death, heart failure hospitalization, heart transplant) collected within the next 2.5 years and adjudicated blindly constituted the censoring variables. RESULTS: Within the first 6 months of resynchronization QoL improved in 81%, while worsening in 19% of patients. Clinical response, but not the echocardiographic one, was associated with improved QoL. During subsequent 2.5 years MACEs occurred in 37% of patients (23% died). Subjects without QoL improvement were significantly (both P < 0.05) more prone to experience MACE (61% vs 32%) and die (44% vs 18%) within the follow-up. Unimproved QoL increased the probability of future MACE by 2.7 times (95% confidence intervals [CI]: 1.26-5.83; P = 0.01) and death by 3.2 times (95% CI: 1.23-8.32; P = 0.02) independently from clinical and echocardiographic response. CONCLUSIONS: Clinical response, but not the echocardiographic one, was associated with improved QoL in CRT recipients. These preliminary data suggest that lack of improvement in QoL after CRT was associated with a strongly unfavorable prognosis, regardless of functional or echocardiographic response. Our results merit further studies with a larger number of patients.

Efficacy of cardiac resynchronisation therapy in the treatment of end-stage inotrope-dependent heart failure patients.

BACKGROUND AND AIM: Currently, cardiac resynchronisation therapy (CRT) is recommended only for New York Heart Association (NYHA) class IV ambulatory patients. However, some recent reports have suggested that CRT could also be beneficial for end-stage inotrope-dependent heart failure (HF) NYHA class IV patients. In this report, we summarise the results of CRT implantation in a group of 11 HF inotrope-dependent patients who were not candidates for urgent orthotopic heart transplantation (OHT). METHODS AND RESULTS: Between August 2006 and June 2011, 11 end-stage inotrope-dependent HF patients with wide QRS complex, ineligible for urgent OHT, were implanted with CRT in the Silesian Centre for Heart Diseases in Zabrze. Dependence on inotropic therapy was defined as an inability to stop the infusion of the drug without the occurrence of hypotension, oligooranuria and/or hypoxaemia. All patients were successfully implanted with CRT and subsequently weaned from inotropes in a median time of two (1-17) days. Mean QRS duration shortened from 190 ± 34 ms at baseline to 142 ± 25 ms (p < 0.001) after the procedure. Average left ventricular ejection fraction increased from 19 ± 4% to 25 ± 4% (p < 0.001). All patients were discharged from hospital. Median hospital stay after the procedure was ten (5-56) days. During the median follow-upof 1,212 (182-2,048) days, four patients died (one due to arrhythmic storm, three others due to progressive pump failure). During that period, 57 adequate device interventions occurred in three patients, including 52 therapies in one fatal case. CONCLUSIONS: CRT can be an alternative for end-stage inotrope-dependent HF patients with wide QRS who are ineligible for urgent heart transplantation.

Trying to predict the unpredictable: Variations in device-based daily monitored diagnostic parameters can predict malignant arrhythmic events in patients undergoing cardiac resynchronization therapy.

BACKGROUND: The aim of this study was to evaluate the value of device-based diagnostic parameters in predicting ventricular arrhythmias in cardiac resynchronization therapy (CRT) recipients. METHODS: Ninety-six CRT-D patients participating in TRUST CRT Trial were analyzed. The inclusion criteria were: heart failure in NYHA ≥ 3 class, QRS ≥ 120 ms, LVEF £ 35% and significant mechanical dyssynchrony. Patients were divided into those with (n = 31, 92 arrhythmias) and without (n = 65) appropriate ICD interventions within follow-up of 12.03 ± 6.7 months. Daily monitored device-based parameters: heart rate (HR), thoracic impedance (TI), HR variability and physical activity were analyzed in 4 time windows: within 10, 7, 3 days and 1 day before appropriate ICD interventions. RESULTS: A consistent pattern of changes in three monitored factors was observed prior to arrhythmia: 1) a gradual increase of day HR (from 103.43% of reference within 10-day window to 105.55% one day before, all p < 0.05 vs. reference); 2) variations in night HR (104.75% in 3 days, 107.65% one day before, all p < 0.05) and 3) TI decrease (from 97.8% in 10 days to 96.81% one day before, all p < 0.05). The combination of three parameters had better predictive value, which improved further after exclusion of patients with atrial fibrillation (AF). The predictive model combining HR and TI together with LVEF and NT-proBNP was more prognostic than the model involving LVEF and NT-proBNP alone (difference in AUC 0.05, 95% CI 0.0005-0.09, p = 0.04). CONCLUSIONS: Daily device-monitored parameters show significant variations prior to ventricular arrhythmia. Combination of multiple parameters improves arrhythmia predictive performance by its additive value to baseline risk factors, while presence of AF diminishes it.

Long-term outcomes of cardiac resynchronization therapy are worse in patients who require atrioventricular junction ablation for atrial fibrillation than in those with sinus rhythm.

BACKGROUND: The aim of the study was to assess the impact of atrial fibrillation (AF) with and without the need for atrioventricular junction (AVJ) ablation on outcomes in patients undergoing cardiac resynchronization therapy (CRT). METHODS: A single center cohort of 200 consecutive CRT patients was divided into three groups: 1) AF with CRT pacing < 95% in which AVJ ablation was performed (AF-ABL, n = 40; 20%), 2) AF without the need for AVJ ablation (AF-non ABL, n = 40; 20%), 3) sinus rhythm (SR, n = 120; 60%). All patients were assessed before CRT implantation and at 6-month follow-up. Positive clinical response to CRT was considered alive status without the need for heart transplantation and improvement ≥ 1 NYHA after 6 months. The comparative analysis among all study groups with respect to response-rate and long-term survival was performed. RESULTS: The 6-month response-rate in both AF-ABL and AF-nonABL was significantly lower than in SR (52.5 and 50 vs.77.5%, respectively; both p < 0.017), though there were no differences in baseline characteristics among study groups apart from higher baseline NT-proBNP levels in AF-ABL. However, after adjustment for this confounder, and despite optimal CRT pacing burden in study groups, the remote all-cause mortality during median follow-up of 36.1 months was significantly higher in AF-ABL than in SR (adjusted HR = 2.57, 95% CI 1.09-6.02, p = 0.03). What is more, no difference in long-term survival between SR and AF-nonABL was observed. CONCLUSIONS: Despite the improvement of CRT pacing burden and thus response-rate up to the level of AF subjects without the need for ablation, the long-term survival of AF patients requiring AVJ ablation remains still worse than in SR.