Treatment of atrial fibrillation with second-generation cryoballoon followed by contact-sensing radiofrequency catheter ablation for arrhythmia recurrences-results of a 5-year follow-up.

INTRODUCTION: The aim of this study was to report the long-term follow-up results of cryoballoon (CB) ablation in patients with atrial fibrillation. METHODS: All consecutive patients who underwent second-generation CB ablation from February 2015 to December 2017 were included in our study. In all procedures, we used a 28-mm CB placed via a single transseptal puncture guided by intracardiac ultrasound. A 20-mm octapolar intraluminal circular catheter was used for intracardiac recordings. A single 180-s freeze strategy was employed. Repeated procedures were performed with a 3D mapping system and radiofrequency catheters. RESULTS: A total of 126 patients (69.8% male, mean age 57 ± 11 years), of which 77.0% had paroxysmal atrial fibrillation (PAF), were included in the study. After a 5-year period, 52.4% of patients were in sinus rhythm without AF recurrence, off antiarrhythmic drugs. A total of 61.9% of patients were free of AF recurrence when redo PVI procedures were performed. When accounting for redo pulmonary vein isolation and antiarrhythmic drugs, a total of 73.8% of the patients were without AF recurrence in long-term follow-up. The patients who underwent redo pulmonary vein isolation procedures had statistically significant lower rates of AF recurrence (p = 0.006). In patients with PAF, long-term success rates improved from 62.9 to 79.4% for patients who underwent the redo procedure (p = 0.020). In patients with persistent atrial fibrillation (PersAF), success rates went up from 41.4 to 55.1% for patients with single or repeated PVI procedure (p = 0.071). In the whole cohort, a total of 3 (2.4%) procedure-related major complications occurred which included persistent PNP, arterial pseudoaneurysm, and arteriovenous fistula. CONCLUSION: Our data suggest a favorable long-term safety and efficacy profile of second-generation CB ablation. In the mixed paroxysmal and persistent population, up to 73.8% of patients remained free of AF recurrence in the 5-year follow-up, when accounting for redo procedures and AADs. Only 2.4% of patients experienced major complications of the ablation procedure, none with permanent sequelae.

Feasibility and safety of reprocessing of intracardiac echocardiography catheters for electrophysiology procedures - a large single center experience.

PURPOSE: Intra-cardiac echocardiography (ICE) has become an important tool for catheter ablation. Adoption of ICE imaging is still limited because of its prohibitively high cost. Our aim was to study the safety and feasibility of ICE catheters reprocessing and its environmental and financial impact. METHODS: This was a single center retrospective analysis of all consecutive electrophysiology procedures in which ICE catheters were used from 2015 to 2022. In total, 1128 patients were studied (70.6% male, mean age was 57.9 ± 13.2 years). The majority of procedures were related to atrial fibrillation ablation (84.6%). RESULTS: For the whole cohort, 57 new ICE catheters were used. Consequently one catheter could be used for 19.8 procedures. New catheters were only used when the image obtained by reused probes was not satisfactory. There were no cases of ICE probe steering mechanism malfunction, no procedure related infections and no allergic reactions that could be attributed to the resterilization process. In total, there was 8.6% of complications not related to ICE imaging. Financially, ICE probe reprocessing resulted with 90% cost reduction (> 2 millions of Euros savings for the studied period) and 95% waste reduction (639.5 kg less, mostly non degradable waste was produced). CONCLUSION: Our data suggests that ICE catheter reprocessing is feasible and safe. It seems that risk of infection is not increased. Significant economic and environmental savings could be achieved by ICE catheters reprocessing. Furthermore, ICE reprocessing could allow more extensive ICE usage resulting in safer procedures with a potential reduction of serious complications.

Radiation dose reduction in the setting of cryoballoon ablation for atrial fibrillation: the value of optimized fluoroscopy settings and intracardiac echocardiography.

Cryoballoon (CB) has proven to be very effective in the percutaneous treatment of atrial fibrillation (AF). CB ablation is still hampered by X-ray exposure and the doses applied are consistently higher if compared to radiofrequency ablation. All patients who underwent CB ablation between 2015 and 2020 were analysed. Intracardiac echography was consistently used for transeptal puncture. To demonstrate the differences in radiation exposure 3 groups of 50 consecutive patients were selected. In the first group (G1) 3D rotational angiography (3DRA) was used as an intraprocedural imaging method. In the second group (G2), traditional X-ray imaging was used and frame rates both for fluoro and cine modes of diascopy were lowered. In the third group (G3) only 2-3 frames per second were used, cine mode was abandoned and the grid was removed from the X-ray detector. A total of 150 patients were included (76% males, mean age 57.3 ± 11.5 years). A dramatic reduction of radiation dose was obtained from 9585 ± 5610 µGy/m2 in G1 to 2469 ± 2002 µGy/m2 in G2 and finally 227.1 ± 360 µGy/m2 in G3 (p < 0.0001). There was also a significant decrease of procedural and fluoroscopy times. No difference in major complications and midterm outcomes was found between the groups. By following a few relatively simple steps (omitting the pre-procedural imaging, removing grid from the X-ray detector and using very low frame rates) CB ablation could be performed with ultralow radiation exposure without compromising the safety of efficacy of the procedure.

Intra-procedural three-dimensional rotational angiography in cryoballoon ablation for atrial fibrillation.

Cryoballoon (CB) is an established technology for atrial fibrillation (AF) ablation and is usually performed using solely fluoroscopy. We aimed to study the feasibility of three-dimensional rotational angiography (3DRA) as intra-procedural imaging in CB ablation. Analyzed data were retrospectively collected from patients that underwent second generation CB ablation from February 2015 to August 2017. We studied 68 consecutive patients that received 3DRA (3DRA group). Sixty-six patients who received conventional X-ray imaging served as a control group. 3DRA was performed via an introducer placed in the left atrium. Angiographic images were segmented and fused with live fluoroscopy to guide the ablation. We have analyzed 134 CB patients (73.8% male, 56.9 ± 11.4 years). Paroxysmal AF was present in 77.6% of patients. 3DRA was successfully performed in all 3DRA group patients. The mean procedure time was significantly shorter in the control group (82.4 ± 26.3 min) than in the 3DRA group (121.1 ± 21.4 min) (p < 0.0001). Total radiation dose (419.3 ± 317.9 vs 998.3 ± 673 mGy, p < 0.0001) and contrast administration (83.2 ± 22.3 mL vs 191.6 ± 33.4 mL, p < 0.0001) were significantly lower in control group. There was no significant difference in 2-year success rate, 35.2% of patients had AF recurrence in the 3DRA group and 30.3% in the control group (p = 0.584). Major complications occurred in 2.9% and 1.5% of patients in 3DRA group and control group, respectively (p = 1.000). 3DRA is a feasible method of intra-procedural imaging to guide CB ablation. However, it prolongs procedure time, increases radiation dose and contrast administration with no significant effect on procedure outcomes and complication rates.

Use of figure of eight suture for groin closure with no heparin reversal in patients undergoing cryoballoon ablation for atrial fibrillation.

PURPOSE: We aimed to demonstrate the feasibility of figure of eight (FoE) suture for groin access closure in cryoballoon (CB) ablation and its impact on the lab workflow. METHODS: We retrospectively analyzed all patients who underwent CB ablation in our institution from June 2018. From June 2019, we have been consistently using FoE suture for hemostasis (FoE+ group), and before that conventional manual compression was utilized (FoE- group). Ablations were performed under uninterrupted oral anticoagulant strategy. Both femoral veins were punctured, and a single introducer was placed in each vein. In the FoE- group, after ablation, protamine was administered, and manual compression was applied. In the FoE+ group, the suture was placed in both groins without protamine administration and manual compression. All patients were in decubitus position until the next morning. RESULTS: A total of 190 consecutive patients (73.2% male, 59.7 ± 11.0 years old) were evaluated, 90 being in the FoE+ group. There was no difference in the mean procedure duration between two groups (72.7 ± 23.1 min vs 73.7 ± 27.1 min, p = 0.784). However, the total lab time was significantly longer in FoE- group (132.9 ± 35.3 min vs 109.9 ± 32.6 min, p < 0.0001). There was no difference in complication rates. No major vascular complications were found in our cohort. CONCLUSIONS: Utilization of FoE sutures for hemostasis seems to be a safe and effective after cryoballoon ablation. It abolishes the need for protamine administration which can cause serious adverse events. As manual compression is unrequired, EP lab workflow improves due to significantly shortened total lab time per patient.

Improved real-time recordings using the fourth-generation cryoballoon technology-detection of dual fascicle electrograms.

BACKGROUND: We aimed to analyze the rate of visualization of real-time (RT) recordings and dual fascicle electrograms in our first series of patients treated with the fourth-generation cryoballoon (CB) device. METHODS: All consecutive patients who underwent CB ablation using the fourth-generation technology were included in the analysis. In all procedures, we used a 28-mm CB placed via a single transseptal puncture guided by intracardiac ultrasound. A 20-mm octapolar intraluminal circular catheter was used for intracardiac recordings. A single 180-s freeze strategy was employed. RESULTS: A total of 129 patients (72.9% male, mean age 60.1 ± 10.9 years) were enrolled in the study. RT recordings were detected in 445 (86.2%) pulmonary veins (PVs). Specifically, RT recordings were visualized in 115 left superior PVs (89.2%), 107 left inferior PVs (82.9%), 118 right superior PVs (91.4%), and 105 right inferior PVs (81.3%). Dual fascicle electrograms could be observed only in patients in sinus rhythm, in 23 of 396 PVs (5.8%). They were most commonly observed in the left superior PV (8.1%), somewhat less in both inferior veins (6.1%), while this phenomenon was least frequent in the right superior PV (3.0%). CONCLUSIONS: By using the fourth-generation CB, we report a specific pattern of isolation represented by a sequential isolation of two apparently distinct PV fascicles during a single CB freeze delivery. This phenomenon occurred in 5.8% of PV ablations. Of note, the rate of visualization of RT isolation with this novel CB was very high and could be documented in 86.2% of PVs.

Learning curves in atrial fibrillation ablation - A comparison between second generation cryoballoon and contact force sensing radiofrequency catheters.

OBJECTIVE: To examine the learning curves of atrial fibrillation (AF) ablation comparing the cryoballoon (CB) and radiofrequency (RF) catheters. METHODS: We performed a retrospective data analysis from the initiation of AF ablation program in our center. For CB ablation, a second generation 28 mm balloon was utilized and for RF ablation. RESULTS: A total of 100 consecutive patients (50 in each group) have been enrolled in the study (male 74%, mean age 58.9 ± 10 years, paroxysmal AF 85%). The mean procedure time was shorter for CB (116.6 ± 39.8 min) than RF group (191.8 ± 101.1 min) (p < 0.001). There was no difference in the mean fluoroscopy time, 24.2 ± 10.6 min in RF and 22.4 ± 11.7 min in CB group, (p = 0.422). Seven major complications occurred during the study; 5 in RF group (10%) and 2 in CB group (4%) (p = 0.436). After the mean follow up of 14.5 ± 2.4 months, 15 patients in RF group (30%) and 11 in CB group (26%) experienced AF recurrences (P = 0.300). CONCLUSION: When starting a new AF ablation program, our results suggest that CB significantly shortens procedure while fluoroscopy time and clinical outcomes are comparable to RF ablation.

TWARMI pilot trial: The value and optimal criteria of microvolt T-wave alternans in the diagnosis of reversible myocardial ischemia in patients without structural cardiac disease.

AIMS: Microvolt T-wave alternans (MTWA) testing is a beat-to-beat fluctuation in the amplitude of T wave. We investigated whether: (a) MTWA can be new non-invasive tool for detection of reversible ischemia in patients with suspected CAD without structural heart disease, (b) MTWA can detect ischemia earlier and with greater test accuracy compared with exercise ECG ST-segment testing, and (c) threshold value of MTWA and heart rate at which the alternans is estimated can be different compared to standard values. METHODS: A total of 101 patients with suspected stable coronary disease, but without structural heart disease, were included. Echocardiography, exercise ECG test, MTWA with classical and modified threshold alternans values, and coronary angiography were performed. RESULTS: About 33.3% patients had a false-positive result on exercise ECG test. The sensitivity of exercise ECG ST-segment test in the detection of coronary artery disease was 97.8%, and the specificity was 42.5% (DOR 33.89). In a group of angiographically positive patients, standard MTWA accurately identified 60% of patients, while 40% had a false-negative result. About 91.8% patients with negative angiography result were accurately identified with 8.2% false positives. The sensitivity of MTWA was 59.61% and specificity 91.83%. Best ratio of sensitivity and specificity (86.53% and 95.91%, DOR 151.06) had modified criteria for positive MTWA (MTWA >1.5 µV at heart rate 115-125/min). CONCLUSIONS: This study showed that MTWA can be the new non-invasive tool for the detection of reversible ischemia in patients with suspected CAD without structural heart disease. Also, MTWA can detect ischemia earlier and with greater accuracy compared with exercise ECG testing.

[ATRIAL FIBRILLATION AND HEMODINAMICALY UNSTABLE WIDE QRS COMPLEX TACHYCARDIA ­ A case report].

Tachycardia is an arrhythmia characterized by heart rate > 100 / minute. According to the width of the QRS complex it can be divided into narrow QRS (< 120 ms) and wide QRS tachycardia (> 120 ms). Narrow QRS tachycardia is always supraventricular which means that its source is proximal to the bundle of His, while wide QRS tachycardia can be ventricular (source is in the ventricle, distal to the bundle of His) or supraventricular. The strategies for treating these two conditions are different so the correct diagnosis is prerequisite for optimal therapy. We present this case because the differential diagnosis of wide QRS tachycardia and therefore the treatment planning was particularly difficult due to concurrently present atrial fibrillation with hemodynamic compromise and an acute threat to the life of the patient.

[EUROPEAN RESUSCITATION COUNCIL GUIDELINES FOR RESUSCITATION 2015].

Adult basic life support and automated external defibrillation ­ Interactions between the emergency medical dispatcher, the bystander who provides CPR and the timely deployment of an AED is critical. All CPR providers should perform chest compressions, those who are trained and able should combine chest compressions and rescue breaths in the ratio 30:2. Defibrillation within 3­5 min of collapse can produce survival rates as high as 50­70%. Adult advanced life support ­ Continued emphasis on minimally interrupted high-quality chest compressions, paused briefly only to enable specific interventions, including interruptions for less than 5 s to attempt defibrillation. Use of self-adhesive pads for defibrillation. Waveform capnography to confirm and continually monitor tracheal tube placement, quality of CPR and to provide an early indication of return of spontaneous circulation. Cardiac arrest in special circumstances ­ Special causes: hypoxia; hypo-/hyperkalemia, and other electrolyte disorders; hypo-/hyperthermia; hypovolemia; tension pneumothorax; tamponade; thrombosis; toxins. Special environments are specialised healthcare facilities, commercial airplanes or air ambulances, field of play, outside environment or the scene of a mass casualty incident. Special patients are those with severe comorbidities and with specific physiological conditions. Post resuscitation care is new to the ERC Guidelines. Targeted temperature management remains, now aiming at 36°C instead of the previously recommended 32 ­ 34°C. Pediatric life support ­ For chest compressions, the lower sternum should be depressed by at least one third the anterior-posterior diameter of the chest (4 cm for the infant and 5 cm for the child). For cardioversion of a supraventricular tachycardia (SVT), the initial dose has been revised to 1 J kg­1. Resuscitation and support of transition of babies at birth ­ For uncompromised babies, a delay in cord clamping of at least one minute from the complete delivery of the infant, is now recommended for term and preterm babies. Tracheal intubation should not be routine in the presence of meconium and should only be performed for suspected tracheal obstruction. Ventilatory support of term infants should start with air. Acute coronary syndrome (ACS) ­ Pre-hospital recording of a 12-lead electrocardiogram (ECG) is recommended in patients with suspected ST segment elevation acute myocardial infarction (STEMI). Patients with acute chest pain with presumed ACS do not need supplemental oxygen unless they present with signs of hypoxia, dyspnea, or heart failure. In geographic regions where PCI facilities exist and are available, direct triage and transport for PCI is preferred to pre-hospital fibrinolysis for STEMI. First aid is included for the first time in the 2015 ERC Guidelines. Principles of education in resuscitation ­ Directive CPR feedback devices are useful for improving compression rate, depth, release, and hand position. Whilst optimal intervals for retraining are not known, frequent 'low dose' retraining may be beneficial. Training in non-technical skills is an essential adjunct to technical skills. The ethics of resuscitation and end-of-life decisions ­ Ethical principles in the context of patient-centered health care: autonomy, beneficence, non-maleficence; justice and equal access. The need for harmonisation in legislation, jurisdiction, terminology and practice still remains within Europe.

[The first case of radiofrequent ablation of ventricular tachycardia in a patient with ischemic cardiomyopathy in our country]. / Prvi slucaj radiofrekventne ablacije ventrikularne tahikardije kod bolesnika s ishemijskom kardiomiopatijom u nasoj zemlji.

Ablation of ventricular tachycardia in patients with ischemic cardiomyopathy is more complicated and more difficult than ablation of most supraventricular tachycardias. Arrhythmogenic substrate is complex and its localisation is often unclear. Because of the tachycardia characteristics, more precise mapping methods often can't be utilised. Also, patients are usually seriously ill with decreased systolic function, heart failure, ischemia and various comorbidities where tachycardia induction and ablation procedure may facilitate abrupt hemodynamic disturbance. Uninducibility of the clinical tachycardia can be achieved in 65-95% of patients, but tachycardia recurs in 20-44% of patients. Serious complications were noted in 8% of patients with lethal outcome in 2.7% of patients. Decision about therapeutic strategy should be made individually according to potential risk and procedure benefit. This paper presents the first case of the successful ablation of ventricular tachycardia in a patient with ischemic cardiomyopathy in our country.

Cardiac arrest in a patient with Ebstein's anomaly without accessory pathways.

We describe a case report of a patient with cardiac arrest and Ebstein's anomaly. This case report shows us necessity for arrhythmia evaluation and sudden death risk stratification even in asymptomatic patients. Prophylactic ICD implantation in this patient population is limited to observational studies and the selection of patients is impeded by the absence of randomized trials and weak predictors.

Quality of life after cardiac surgery.

The aim of this study was to determine a health-related quality of life two or more years after a cardiac surgery using the MOS-36 item short-form health survey questionnaire. 330 members of "Croatian society of patients who underwent cardiac surgery" were asked and 196 responders, 122 men and 74 women, were included in survey, all of them more than two years after surgery and older than fifty years of age. The answers were collected by phone. Women gained better results for Physical Functioning (p < 0.003) and men estimated better scores for psychical health (p < 0.001). Our patients gained some different results in respect to the Croatian sample of healthy people of the same age. They declared better General Health (p < 0.001), less Bodily Pain (p < 0.001), but inferior Role-Emotion (p < 0.001) and Social Functioning (p < 0.001). The estimations of QOL improving were comparable with the results of numerous shorter follow-ups.

Behaviour after cardiosurgery.

Aim of this study was to estimate behavioral changes after cardiac surgery (CS). A questionnaire was sent by mail to 74 women and 122 men during May 2004 and the answers were collected by phone. For statistical analysis, the chi2-test was used. A common unhealthy habits before CS were inappropriate diet (80% of all responders), addictions to alcohol (62%) and nicotine (54%). Significantly fewer patients after CS continue with fatty diet (chi2 = 39.069; p < 0.001), smoking (chi2 = 90.286; p < 0.001) and alcohol drinking habits (chi2 = 60.667; p < 0.001). A significant worsening of sexual life (chi2 = 91.533; p < 0.001) and significantly less negative influence of weather changes (chi2 = 20.821; p < 0.001) was found after CS. Men drink more (chi2 = 16.299; p < 0.001) and smoke more (chi2 = 19.635; p < 0.001), have better sexual life (chi2 = 17.317; p < 0.001), fewer sleeping disorders (chi2 = 17.334; p < 0.001) and better oral health (chi2 = 38.632; p < 0.001) than women. These results can be useful for setting up preventive measures for CVD.

[Influence of electrical cardioversion on troponine I and brain natriuretic peptide (NT-proBNP) levels in patients with persistent atrial fibrillation/flutter]. / Utjecaj elektrokonverzije na vrijednosti troponina I i mozdanog natriuretskog peptida (NT-proBNP) u bolesnika s perzistentnom fibrilacijom/undulacijom atrija.

The goal of our research was to determine how electrical cardioversion influences troponine I and brain natriuretic peptide (NT-proBNP) levels in patients with persistent atrial fibrillation (AF), without heart failure. Reaserch was conducted on 20 patients with AF. Before and after cardioversion levels of troponine I, creatine-kinase (CK), lactate-dehydrogenase (LDH) and brain natriuretic peptide (NT-proBNP) were measured. Average total applied energy was 344,2 +/- 268,9 Joule. After cardioversion CK level was insignificantly higher (113,3:259,0). Levels of troponine I did not change significantly after cardioversion (0,185:0,202). By measuring levels of NT-proBNP significantly lower levels of NT-proBNP were found after cardioversion (1095:432). There was a strong correlation between the duration of arrhythmia and the NT-proBNP level. Electrical cardioversion with standard recommended energy does not cause significant myocardial lesion. CK level elevation is a consequence of skeletal muscle lesion. Possible elevation of troponine I should be interpreted by another etiology. Increased production of BNP is caused by increased pressure and volume overload of the atrium, in patients with AF, independent of global cardiac function, according to that we think that in patients with AF discriminatory values of BNP in heart failure diagnostics should be corrected to higher levels.

Heart rate variability differences in post-myocardial infarction patients based on initial treatment during acute phase of disease.

The aim of study was to asses the heart rate variability (HRV) differences in 128 post-myocardial infarction (MI) patients based on initial treatment during acute phase of disease. The patients were divided into groups: group 1 patients who underwent primary PCI, group 2 patients who received fibrinolysis and group 3 patients who were treated conservatively. In comparison with groups 2 and 3, group 1 patients had all HRV analyzed parameters higher except for LF/HF ratio. The results of study suggest that patients who were treated by primary PCI had better preserved autonomic cardiac function compared with patients who received fibrinolysis or those who were treated conservatively in the acute phase of MI.

[Present status of cardiac pacing in Croatia]. / Sadasnje stanje elektrostimulacije srca u Republici Hrvatskoj.

The number of implanted cardiac pacemakers in Croatia has considerably increased in the recent years. However, we still have not reached the level of the developed European countries. This particularly applies to the number of implanted cardioverter-defibrillators, and less so to the proportion of simple and sophisticated cardiac pacemakers. Despite this, when indication is established our patients receive top quality and most modern devices, because in Croatia the products of the most renowned world manufacturers are implanted.

[Prevalence of ultraextensive drug metabolizers in Croatian population--long-PCR based detection of amplified CYP2D6 gene]. / Prevalencija vrlo brzih metabolizatora lijekova u hrvatskoj populaciji--detekcija amplificiranog gena CYP2D6 metodom long-PCR.

Cytochrome P450 enzyme debrisoquine 4-hydroxylase, responsible for the metabolism of different classes of drugs and other chemical substances, exhibits genetic polymorphism with great interindividual and interethnic differences in metabolic capacity. The activity of enzyme ranges from very expressed, rapid, to total absence of activity. Up to 7% of Caucasians may demonstrate ultrarapid metabolism--UEM of debrisoquine and other drugs, substrates of debrisoquin hydroxylase, due to inheritance of multiplicate functional CYP2D6 gene, causing an increased amount of enzyme to be expressed. Identification of subjects with ultrarapid metabolism is of potential clinical value for optimization of therapy and avoidance of therapeutic failure due to inadequate dosage. In our study we wanted to determine the prevalence of UEM genotype in Croatian population applying long-PCR method. We found a 4% prevalence of ultrarapid metabolizers with multiplicated CYP2D6 gene.