Recovery Of Sinus Rhythm Research Articles

The results of emergency medical care for patients with paroxysmal atrial fibrillation

The main purpose of the study was to assess the quality and effectiveness of emergency medical care (EMC)in atrial fibrillation paroxysm (AF) at the prehospital stage. Materials and methods: the analysis included 111 patients who called an ambulance due to AF paroxysm. The patients were divided into groups depending on the recovery of sinus rhythm in the presence of a team. A telephone survey of patients was conducted 30 days after seeking medical help. Results: the sinus rhythm in the presence of the brigade was restored in 40% of cases. At the same time, the median recovery time of the rhythm was 32 minutes [Q1–Q3: 29–50]. 9% of patients were hospitalized. 53% of patients refused hospitalization. The probability of rhythm recovery increased with the help of a medical team and was not associated with the choice of an antiarrhythmic and the use of potassium and magnesium drugs. At the same time, in the next 30 days, complications (hospitalization, recurrence of AF and repeated call an ambulance) were observed more often among patients with restored rhythm (43% vs. 12%;p=0.00022). In 60.5% of patients who were trying to restore the rhythm, No anticoagulants were used, and in 7% 2 anticoagulants were used simultaneously. Conclusion. When providing EMC at the prehospital stage, rhythm restoration in the presence of a team is observed in 40% of cases, which is associated with a large number of complications in the next 30 days and a large percentage of errors associated with anticoagulant therapy.

A comparison between stand-alone left atrial appendage occlusion and resection as a method of preventing cardiogenic thromboembolic stroke.

The present study evaluated the differences between left atrial appendage occlusion (LAAO) and left atrial appendage resection (LAAR) in terms of the safety and efficacy. From January 2018 to August 2022, 94 patients underwent a stand-alone LAAO, and 90 patients underwent stand-alone LAAR in our institution. All of these patients were included in this study. LAAO was performed via left mini-thoracotomy, and LAAR was performed via a left thoracoscopic approach. The patients' characteristics and perioperative and postoperative data were obtained by retrospectively reviewing their medical records. The mean age of the patients was 72.4 ± 10.2 (LAAO) and 66.2 ± 9.4 (LAAR) years old (P < 0.05). There were no marked differences in the mean duration of atrial fibrillation (AF) or the ratio of AF type between both groups. The average CHA2DS2-Vasc scores were 4.4 ± 1.6 (LAAO) and 2.7 ± 1.8 (LAAR) (P < 0.05), and the average HAS-BLED scores were 2.9 ± 1.0 (LAAO) and 2.2 ± 1.2 (LAAR) (P < 0.05). The mean operation time was 49 ± 20min (LAAO) and 34 ± 15min (LAAR) (P < 0.05). No substantial gaps were detected in preoperative echo-graphic findings between the groups. No significant differences were observed in the amount of intraoperative or postoperative bleeding or the rate of intraoperative massive bleeding events between the groups. Successful LAA closure was achieved in all cases in both groups. Approximately 50% of patients underwent concomitant left pulmonary vein isolation (LPVI) during surgery, indicating no significant differences between the groups (P = 0.872). The early mortality rate was 1.04% in the LAAO group and 0% in the LAAR group (P = 0.132). There was no significant difference in the rate of postoperative LAA stump thrombus between the groups (8.5% in the LAAO group and 6.7% in the LAAR group; P = 0.320). The mean follow-up period was 851 ± 500 (6-1618) days in the LAAO group and 1208 ± 357 (49-1694) days in the LAAR group. Postoperative stroke events were detected in 1 patient in each group (P = 0.432). There was no significant difference in the sinus rhythm recovery rate after LPVI between these groups (31.1% in the LAAO group and 28.6% in the LAAR group; P = 0.763). There were no significant differences between LAAO and LAAR in terms of the feasibility and the effectiveness as a method for stroke prophylaxis only to selected patients for both procedures, although further studies including the comparison between groups with the same backgrounds to confirm the authentic differences in the clinical results between these procedures.

Preliminary results of a prospective randomized study comparing the efficacy and safety of refralon and amiodarone in cardioversion in patients with paroxysmal atrial fibrillation and flutter

Aim. To compare the efficacy and safety of chemical cardioversion (CCV) with refralon and amiodarone in patients with paroxysmal atrial fibril­lation and flutter (AF/AFL).Material and methods. Fifty five patients (mean age, 65±11 years) with paroxysmal AF/AFL were included. All patients underwent a preliminary examination to rule out contraindications to CCV. Further, patients were randomized into groups of refralon (n=30) and amiodarone (n=28), respectively. CCV with refralon was carried out as follows: administration in doses of 5-5-10-10 µg/kg at intervals of 15 minutes. Patients of the second group were intravenously injected with amiodarone at a dose of 5 mg/kg of body weight for 20-60 minutes, depending on the drug tolerability. If AF/AFL persists after 60 minutes, infusion of amio­darone 100 mg/hour until restoration of sinus rhythm (SR) or reaching a dose of 1200 mg/day. Treatment efficacy was assessed by SR reco­very, absence of AF/AFL recurrence, and arrhythmia relief time, and safety was assessed by detection of ventricular arrhythmogenic effects, bradyarrhythmias, blood pressure reduction, and QT interval prolongation. The follow-up period lasted 24 hours.Results. SR was restored in 96,7% (n=29) of patients in the refralon group, of which 56,7% (n=17) after a dose of 5 mcg/kg. In the amio­darone group, SR was restored in 57,1% (n=16) of patients (p&lt;0,001). The arrhythmia relief time in the refralon group was 14 [7;23] min, while in the amiodarone group — 150 [82;240] min (p&lt;0,001). There were no significant differences in the incidence of bradyarrhythmias, lowering blood pressure, and QT prolongation in the groups.Conclusion. Refralon demonstrates a higher efficiency and lower time to AF/AFL relief compared with amiodarone, while in most patients, SR recovery occurs after the administration of the lowest doses, which ensures CCV safety.

MP-453081-9 CARDIAC SYMPATHOEXCITATION MONITORING DURING PULMONARY VEIN ISOLATION BY PSYCHOGENIC SWEATING: POSSIBILITY OF REPRESENTING CARDIAC SYMPATHETIC NEUROMODULATION

Vagal responses during pulmonary vein isolation (PVI) have been reported, suggesting cardiac neuromodulation in atrial fibrillation (AF) patients. The cardiac sympathetic nervous system also innervates the left atrium (LA) and its nerve fibers are reported to be greatly distributed around the PV antrum. However, the sympathetic nervous system’s response during PVI is unclear and the precise method to evaluate the cardiac sympathetic reflex is still not established. Psychogenic sweating (skin potential response; SPR) occurs during sympathetic excitation and may be useful to represent cardiac sympathoexcitation during PVI. We investigated whether the SPR could represent a cardiac sympathetic response during a balloon-based PVI and considered its clinical implications in persistent AF patients. Eighty persistent AF patients (Hot-balloon;45pt, Cryoballoon;35pt) were enrolled and the SPR was monitored during balloon-based ablation of each PV. The SPR was measured by the difference in two skin potentials recorded from skin electrodes (Figure top row). The reduction in the activation recovery interval (ARI), suggesting sympathetic excitation, was examined from the ventricle unipolar electrogram of the great cardiac vein recorded from an electrode catheter placed inside the coronal sinus (Figure bottom row). An ROC analysis was used to determine a valid reduction in the SPR, with a reduction cut-off value of 3.5mV in the heart rate (HR) increase due to sympathoexcitation (sensitivity 73%, specificity 97%). SPRs occurred in 41% of the PVs (LSPV=41%, RSPV=38%, LIPV=28%, RIPV=20%). The SPR was related to a significant increase in the blood pressure and HR, and a reduction in the ARI (p<0.01, Table). A total of 18 patients (20%) had AF recurrences within the 1-year follow-up. The number of SPRs within the 4PVs was 1.08PV in non-recurrence patients and 1.83PV in AF recurrent patients (p=0.07). The patients that had early recurrences but recovered sinus rhythm (SR) within 3 months, had more frequent SPRs than the other recurrent patients (2.80 vs. 0.63PV, p<0.01). The SPR was strongly related to cardiac sympathoexcitation during PVI. The SPR was suggested to represent the cardiac sympathetic reflex during PV antrum ablation, which may lead to an investigation of the cardiac sympathetic neuromodulation during PVI. Frequent SPRs were related to SR recovery after early AF recurrences and a cardiac sympathetic response may have an important role in the outcome of the PVI.

Effectiveness of pharmacological cardioversion of new-onset atrial fibrillation during thoracic surgery operations: a single-centre experience

ObjectiveProphylactic pharmacological conversion agents could reduce the incidence of postoperative atrial fibrillation (AF) in patients undergoing thoracic operations. The current study examined whether the use of pharmacological conversion agents could help to restore sinus rhythm in patients with AF newly developed during thoracic operations.MethodsMedical records of 18,605 patients from January 1, 2015 to December 31, 2019, at the Shanghai Chest Hospital were reviewed. Patients with non-sinus rhythm prior to the surgery (n = 128) were excluded from data analysis. The final analysis included 18,477 patients (n = 16,292 undergoing lung operations; n = 2,185 undergoing esophageal operations).ResultsIntraoperative AF (defined as AF lasting for at least 5 min) occurred in 646 out of a total of 18,477 subjects (3.49%). Within the 646 subjects, 258 received pharmacological conversion agents during the surgery. sinus rhythm was restored in 20.15% (52/248) of patients treated with pharmacological cardioversion and in 20.87% (81/399) patients not receiving pharmacological intervention. In a subgroup analysis of the 258 patients receiving pharmacological conversion agents, recovery of sinus rhythm was highest in beta-blocker group (35.59%, 21/59 vs. 15.78%, 15/95 in amiodarone group, p = 0.008, 5.55%, and 1/18 in amiodarone plus beta-blockers group, p = 0.016). The incidence of hypotension was higher in pharmacological conversion (27.5% vs. 9.3% in patients not receiving pharmacological intervention, p < 0.001). In subjects not recovering to sinus rhythm during the surgery (n = 513), electrical cardioversion in post-anesthesia care unit (PACU) restored sinus rhythm in > 98% of the cases (155/158 vs. 63/355 in subjects not receiving cardioversion; p < 0.001).ConclusionsOur experience shows that pharmacological conversion, in general, failed to show better treatment effectiveness on intraoperative new-onset AF within period of surgery except for beta-blockers. Patients with AF persisting beyond the surgery could be effectively managed with electrical cardioversion.

Electrocardiostimulation in acute poisoning with antiarrhythmic drugs in children (clinical case)

Severe poisoning with cardiotropic drugs in children, accompanied by pronounced rhythm disorders and low cardiac output syndrome, is quite rare, but sometimes they can end fatally.The objective was to demonstrate the successful use of electrocardiostimulation in acute propafenone poisoning in a child of three years old.Materials and Methods. A retrospective analysis of the features of the course of severe propafenone poisoning in a three-year-old child who required pacing was carried out. Special attention was paid to the analysis of rhythm disorders that led to cardiac arrest by the type of electrical activity without a pulse, high efficiency of timely electrocardiostimulation in order to relieve bradyarrhythmia. Against the background of the therapy, a stable recovery of the correct sinus rhythm was achieved six hours after the connection of a temporary electrocardiostimulator.Conclusion. The presence of persistent bradyarrhythmia-type rhythm disorders in acute poisoning with antiarrhythmic drugs in children is an indication for the emergency use of electrocardiostimulation.

Effects of Atrial Fibrillation Radiofrequency Ablation in Patients Aged &gt; 75 Years Undergoing Mitral Valve Surgery

Few data exist about the efficacy of radiofrequency (RF) maze procedures in elderly patients with atrial fibrillation (AF) undergoing surgery for mitral valve disease. The aim of the present investigation was to evaluate the effects of AF ablation associated with mitral valve surgery on the recovery and long-term maintenance of sinus rhythm in elderly patients aged > 75 years. Moreover, we evaluated the effects on survival. This study included 96 consecutive patients with AF (42 men and 56 women) aged > 75 years (mean age 78 ± 3) who underwent RF ablation associated with mitral valve surgery (group I). This group was compared to 209 younger patients (mean age 65 ± 8 years) treated in the same period (group II). Baseline clinical and echocardiographic characteristics were similar in the two groups. Four patients died during hospitalization, one aged > 75 years. In surviving patients at the end of the follow-up period, sinus rhythm was present respectively in 64% of the elderly and 74% of younger patients (p = 0.778). The rate of persistence of sinus rhythm without AF recurrences (38% vs. 41%, p = 0.705) was similar in the two groups. After surgery, sinus rhythm was frequently never regained in aged patients (27% vs. 20%, p = 0.231). Elderly patients more frequently needed permanent pacing and had more hospitalizations and a higher number of non-AF atrial tachyarrhythmias. At eight-year follow-up, survival was lower in older patients (48% aged > 75 vs. 79% aged < 75 years). Elderly patients had a similar long-term rate of stable sinus rhythm maintenance in comparison to younger patients after AF radiofrequency ablation associated with mitral valve surgery. However, they needed more frequent permanent pacing and had higher rates of hospitalizations and post-procedural atrial tachyarrhythmias. The effects of survival are difficult to evaluate due to the different life expectancies of the two groups.

Prediction of new onset atrial fibrillation recurrence or persistence with artificial intelligence: first insights of the PRAFAI study

Abstract Introduction Atrial fibrillation (AF) is the most prevalent arrhythmia in the world and it is associated with a high rate of cardiovascular morbidity and mortality. A higher burden of atrial fibrillation is related to more adverse cardiovascular events and the rhythm control strategy (maintenance or recovery of sinus rhythm) is particularly indicated in patients with paroxysmal symptomatic atrial fibrillation. All things considered, in order to select the optimal therapeutic strategy, it might be useful to accurately predict the probability of recurrence or permanence of AF after its onset. The predictive models implemented so far, show a limited predictive power or were built on samples of patients undergoing specific therapies. Thus, developing an specific model based on features derived from electronic health records (EHR) of patients with a first AF episode seems essential. Purpose To develop an artificial intelligence powered predictive model based on EHR variables in order to predict the AF recurrence after its onset. Methods The methodological design of the research is based on the analysis of secondary data from a retrospective cohort obtained from the EHR of a tertiary hospital. All new onset AF from 2015 to 2018 were identified by ICD codes, and a 2 years EHR driven follow-up was made to determine the AF recurrence or permanence of the arrhythmia in those patients. A systematic review was pursued to determine which features exhibited a greater predictive power for AF recurrence, and they were inquired to the system for the mentioned participants. After the standardization of the variables and a feature selection process, several missing value imputation methods and around 12 different Machine Learning algorithms were tested to predict the AF recurrence in a subset of patients who developed AF in the first semester of 2015, in order to select the algorithms with the highest prediction accuracy for further tests. Results 523 patients had an AF onset in the first semester of 2015. Among them, 310 (59.3%) had AF recurrence in a 2 years period. A support vector machine (SVM) algorithm with a median imputation method to handle missing values performed the best and had an 0.77 AUC in the training set and 0.71 in the test set. Hyperthyroidism, vasodilator drug use and obstructive sleep apnea were notoriously related to AF recurrence, while Ic antiarrhythmic drugs, AF ablation, cognitive impairment and anxiety were the most influential variables for the absence of recurrence. Classical AF recurrence factors such as age or left atrium diameter ratify their role in this setting. Conclusion A SVM Machine Learning algorithm discloses an accurate AF recurrence probability based on EHR features. Pharmacologic and epidemiological variables, added to classically assessed ones, seem to be specially related to this arrhythmic recurrence. Further research including the whole cohort features will probably improve the accuracy of this selected SVM algorithm. Funding Acknowledgement Type of funding sources: None.

48 A CASE OF RECURRENT VENTRICULAR TACHYCARDIA IN A PATIENT WITH GRANULOMATOSIS WITH POLYANGIITIS WITH A CHALLEGING IDENTIFICATION OF ARRHYTHMIC SUBSTRATE: THE ROLE OF MULTIMODALITY IMAGING

Abstract Background Granulomatosis with polyangiitis (GPA), previously known as Wegener's granulomatosis, is a pulmonary-renal syndrome affecting small and medium sized blood vessels. Cardiac involvement is rare and generally includes pericarditis, myocarditis and aortic valve disease. We report a case of recurrent sustained ventricular tachycardia (VTs) in a patient with GPA. Case summary A 67-year-old man with past medical history of GPA presented palpitations, chest pain and episodes of presyncope. Electrocardiographic tracing upon ED presentation showed sustained monomorphic VT (fig.1) associated with global hypokinesia of the left ventricle and moderately reduced ejection fraction at transthoracic echocardiography (TTE). As the patient was hemodynamically stable, prompt treatment with amiodarone was adopted with successful recovery of sinus rhythm. After a few hours, TTE was normal. However, as troponin I was markedly elevated, coronarography was performed and coronary disease was ruled out. Contrast-enhanced cardiac magnetic resonance imaging (ceCMR) revealed late gadolinium enhancement in basal anteroseptal mid wall, suggestive of myocardial scar tissue with non-ischemic pattern. No sustained ventricular arrhythmias were induced during electrophysiological study (EPS), even with an aggressive protocol (up to 4 extra stimuli and ventricular refractoriness) and electro-anatomical mapping of both ventricles failed to show any arrhythmic substrate. An implantable cardioverter defibrillator (ICD) was then implanted. After 4 months the patient was admitted for multiple episodes of sustained VT (with cycle length in the ICD monitoring window) refractory to drugs and three external defibrillations. Repeated EPS failed to induce sustained arrhythmias. High-density electroanatomical mapping of the right ventricle, however, showed fragmented potentials in the mid-posterior septal wall (fig. 2-3). After myocardial biopsy of the region of interest, radiofrequency catheter ablation of the area was performed with regression of the potentials. The results of endomyocardial biopsy demonstrated fibrosis. At 5 months of follow-up, the patient didn't relapse. Discussion Multimodality imaging is of paramount importance in identifying arrhythmogenic substrate and in characterizing the specific anatomical–functional components of VT circuits. In our patient high-density electroanatomical mapping was able to identify fragmented potentials and define the ablation target area, despite the mismatch with ceCMR.

228 PD-1-TARGETED T-CELL CHECKPOINT INHIBITORS-RELATED MYOCARDITIS COMPLICATED BY COMPLETE ATRIOVENTRICULAR BLOCK: A CASE SERIES OF SUCCESSFUL MANAGEMENT

Abstract Background Immune checkpoint inhibitors (ICI) have revolutionized the clinical management of a broad spectrum of solid and hematopoietic malignancies over the past decade. ICI are associated with several Immune-related Adverse Events, among which myocarditis and atrioventricular blocks are uncommon but potentially fatal toxicities. Material and Methods We describe two patients undergoing treatment with PD-1 checkpoint inhibitors for metastatic cancers who developed myositis and myocarditis complicated by complete atrioventricular block (CAVB). The first patient had a history of metastatic sarcomatoid urothelial carcinoma treated with Pembrolizumab. After two cycles, he developed eyelid ptosis and was hospitalized for syncopal episodes due to CAVB associated with ICI myocarditis. The second patient had a history of metastatic melanoma and was hospitalized for myocarditis and myositis after the second infusion of Nivolumab. Results In the first case, high-dose corticosteroid therapy was promptly initiated, with subsequent rapid recovery of sinus rhythm and rapid resolution of symptoms. The second patient, despite high-dose corticosteroid therapy, developed CAVB requiring implantation of a definitive PM. After initiation of mycophenolate mofetil and intravenous immunoglobulin therapy, gradual recovery was observed. Both patients had normal left ventricular function with no wall motion abnormalities. However, speckle tracking echocardiography revealed a normal global longitudinal left ventricular strain (GLS) of -19.8% in patient 1 and a depressed GLS of -14.7% in patient 2, consistent with the different evolution of the two myocarditis. Conclusions We recommend a high degree of caution and awareness to all physicians when treating immunotherapy patients. Myocarditis is a relatively rare but potentially fatal event due to its early onset, non-specific clinical presentation and fulminant progression. GLS may be useful in detecting myocardial damage in these patients. Discontinuation of ICI, cardiac pacing, treatment with high-dose corticosteroids and immunosuppressive agents may improve the outcome.

Predictors of tachycardia-induced cardiomyopathy in patients with first-time decompensation of chro­nic heart failure with reduced left ventricular ejection fraction of nonischemic etiology and persistent atrial tachyarrhythmia

Aim To identify possible predictors of tachycardia-induced cardiomyopathy (TICMP) in patients with newly developed decompensated chronic heart failure (CHF) of nonischemic origin with reduced left ventricular ejection fraction (LV EF) and with persistent atrial tachyarrhythmias.Material and methods This study included 88 patients with newly developed decompensated CHF of nonischemic origin with reduced LV EF and persistent atrial tachyarrhythmias. Resting 12-lead electrocardiography (EGC) and transthoracic echocardiography (EchoCG) were performed upon admission and following the electrical impulse therapy for all patients. Also, 24-h ECG monitoring was performed to confirm sinus rhythm stability. After recovery of sinus rhythm, outpatient monitoring was performed for three months, including repeated EchoCG to evaluate the dynamics of heart chamber dimensions and LV EF.Results The patients were divided into two groups based on the increase in LV EF: 68 responders (TICMP patients with a LV EF increase by &gt;10%) and 20 non-responders (patients with an increase in LV EF by &lt;10% during 3 months following the sinus rhythm recovery). According to results of the baseline EchoCG, LV EF did not significantly differ in the two subgroups (TICMP, 40±8.3 %, 18-50 % and non-responders, 38.55±7.9 %, 24-50 %); moreover, the incidence of cases with LV EF &lt;30% did not differ either (9 patients TICMP and 2 non-responders, р=1.0). TICMP patients compared to non-responders, had significantly smaller left atrial dimensions (4.53±1.14 (2-7) cm and 5.68±1.41 (4-8) cm, р=0.034; 80.8±28.9 (27-215) ml and 117.8±41.3 (46-230) ml, р=0.03, respectively) and left ventricular end-systolic volume (ESV) (67.7±33.1 (29-140) ml and 104.5±44.7 (26-172) ml, р=0.02, respectively). The effect of major EchoCG parameters on the probability of TICMP development was assessed by one-factor and multifactor regression analyses with adjustments for age and sex. The probability of TICMP increased with the following baseline EchoCG parameters: end-diastolic volume (EDV) &lt;174 ml [odd ratio (OR), 0.115, 95 % confidence interval (CI): 0.035-0.371], ESV &lt;127 ml [OR, 0.034, 95 % CI: 0.007-0.181], left atrial volume &lt;96 ml [OR, 0.08 , 95 % CI: 0.023-0.274], right ventricular dimension &lt;4 cm [OR, 0.042 , 95 % CI: 0.005-0.389].Conclusion Among patients with newly developed decompensation of CHF with reduced LV EF of non-ischemic origin and persistent atrial arrhythmias, TICMP was detected in 72 % of patients. The probability of TICMP did not depend on baseline EF and duration of arrhythmias, but increased with the following baseline EchoCG parameters: EDV&lt; 174 ml, ESV&lt; 127 ml, left atrial volume &lt;96 ml, right ventricular dimension &lt;4 cm. The multifactorial analysis showed that a right atrial volume &lt;96 ml is an independent predictor for the development of TICMP.

Mechanical function of the left atrium within 28 days after restoration of sinus rhythm in patients with paroxysmal atrial fibrillation

Objective: Atrial fibrillation is a strong independent risk factor for cardioembolic stroke, with a significant impact on morbidity, mortality and healthcare costs. The aim of our study is to investigate left atrial mechanical function in healthy subjects and patients with atrial fibrillation paroxysms less than 48 hours with low risk of thromboembolic complications at 1 and 28 days after restoration of sinus rhythm. Methods: Thirty-six healthy controls and patients with paroxysms of non-valvular atrial fibrillation less than 48 hours (n=25) with low-risk CHA2DS2VASc score were included in the study. The mechanical function of the left atrium (LA) was investigated by the 2D speckle tracking program. Transthoracic echocardiography was performed on the 1st and 28th days after restoration of sinus rhythm by pharmacological cardioversion. Results: Despite the absence of differences in left ventricular systolic function and LA size between the groups, there was a significant decrease in LA deformation and strain rate on day 1 immediately after sinus rhythm recovery in the patients. In the pump phase, the decrease was about 3%, reservoir phase – 10%, and conduit phase – 7% compared to the control group. The strain rate also decreased in the patient group: -1.5 s-1 versus control: -2.14 s-1 (p&amp;lt;0.0001). On the 28th day after restoration of sinus rhythm, there were significant changes in reservoir and conduit functions in patients group in comparison with control group. Global longitudinal LA strain (reservoir phase) decreased to 7%, conduit phase decreased to 11% compared with the control group. In patients group we can see the dynamics during 28 days: pump phase and strain rate were significantly improved, however reservoir and conduit did not significantly change and were lower than in healthy. Conclusion: Mechanical function of the LA in patients with non-valvular atrial fibrillation and low risk of thromboembolic complications, studied with speckle tracking on the first day was significantly impaired compared with the control group (reservoir phase and strain rate). By day 28, mechanical function improved compared to day 1, but reservoir phase remained significantly lower than normal.

Abstract 9267: Modified Protocol of Niferidil Administration for Rhythm Restoration in Patients With Paroxysm of Atrial Fibrillation

Introduction: Niferidil is a new Russian class III antiarrhythmic drug, which in clinical trials has shown a high efficiency of restoration of sinus rhythm (SR) in persistent AF (87%), not inferior to electrical cardioversion. Currently, a three-stage scheme of drug administration is used (10 μg / kg - 10 μg / kg - 10 μg / kg). In a number of patients, SR is restored before the end of the first dose of the drug, which indicates the effectiveness of an even lower dose (5 μg / kg) of the drug, which has not been studied in clinical trials. Objective: To evaluate the effectiveness and safety of the modified protocol of niferidil administration in patients with paroxysmal AF. Methods: Included 87 patients with paroxysmal, 42 of them were men, mean age 63 [57;70]. After exclusion of contraindications, all patients received niferidil according to the following scheme. The initial dose of niferidil was 5 μg/kg of body weight, if AF did not terminate after 15 minutes (min.), niferidil was additionally administered at a dose of 5 μg/kg (total dose of 10 μg/kg). If SR was not restored patients received subsequent injections of niferidil 10 μg/kg, each after 15 min. (maximal total dose of 30 μg/kg). Injections were discontinued in case of SR restoration, QTc&gt;500ms or proarrhythmia. All patients underwent continuous ECG monitoring within 24 hours to assess effectiveness and safety of niferidil. Results: SR was restored in 81 out of 87 patients (cumulative effectiveness of niferidil in doses up to 30 μg / kg was 93,1 %. 49,4 % of them restored SR after administration of 5 μg/kg dose, 66 (77 %) - after 10 μg/kg dose, 77 (88,5 %) - after 20 μg/kg dose, 81 (93,1 %) - after 30 μg/kg dose. In none of the cases was there any development of life-threatening ventricular arrhythmias. Prolongation of the QTc&gt;500 ms was recorded in 14 patients (16%). Bradyarrhythmias after SR recovery were reported in 6 patients (6,8 %). In all cases sinus bradycardia was asymptomatic. Conclusions: The modified protocol of cardioversion allows SR to be restored in a significant number of AF patient’s lower doses of niferidil. The drug is highly effective in the treatment of paroxysmal AF, while in almost half of the cases, SR is restored after the administration after drug dose - 5 μg / kg. None of the patients developed Torsades de pointes.

Prediction of new onset atrial fibrillation recurrence or persistence with artificial intelligence: first insights of the PRAFAI study

Abstract Introduction Atrial fibrillation (AF) is the most prevalent arrhythmia in the world and it is associated with a high rate of cardiovascular morbidity and mortality. A higher burden of atrial fibrillation is related to more adverse cardiovascular events and the rhythm control strategy (maintenance or recovery of sinus rhythm) is particularly indicated in patients with paroxysmal symptomatic atrial fibrillation. All things considered, in order to select the optimal therapeutic strategy, it might be useful to accurately predict the probability of recurrence or permanence of AF after its onset. The predictive models implemented so far, show a limited predictive power or were built on samples of patients undergoing specific therapies. Thus, developing an specific model based on features derived from electronic health records (EHR) of patients with a first AF episode seems essential. Purpose To develop an artificial intelligence powered predictive model based on EHR variables in order to predict the AF recurrence after its onset. Methods The methodological design of the research is based on the analysis of secondary data from a retrospective cohort obtained from the EHR of a tertiary hospital. All new onset AF from 2015 to 2018 were identified by ICD codes, and a 2 years EHR driven follow-up was made to determine the AF recurrence or permanence of the arrhythmia in those patients. A systematic review was pursued to determine which features exhibited a greater predictive power for AF recurrence, and they were inquired to the system for the mentioned participants. After the standardization of the variables and a feature selection process, several missing value imputation methods and around 12 different Machine Learning algorithms were tested to predict the AF recurrence in a subset of patients who developed AF in the first semester of 2015, in order to select the algorithms with the highest prediction accuracy for further tests. Results 523 patients had an AF onset in the first semester of 2015. Among them, 310 (59.3%) had AF recurrence in a 2 years period. A support vector machine (SVM) algorithm with a median imputation method to handle missing values performed the best and had an 0.77 AUC in the training set and 0.71 in the test set. Hyperthyroidism, vasodilator drug use and obstructive sleep apnea were notoriously related to AF recurrence, while Ic antiarrhythmic drugs, AF ablation, cognitive impairment and anxiety were the most influential variables for the absence of recurrence. Classical AF recurrence factors such as age or left atrium diameter ratify their role in this setting. Conclusion A SVM Machine Learning algorithm discloses an accurate AF recurrence probability based on EHR features. Pharmacologic and epidemiological variables, added to classically assessed ones, seem to be specially related to this arrhythmic recurrence. Further research including the whole cohort features will probably improve the accuracy of this selected SVM algorithm. Funding Acknowledgement Type of funding sources: None.

The effect of different preoperative left atrial appendage emptying speeds on left atrial function in patients with persistent atrial fibrillation after left atrial appendage closure combined with catheter ablation

ObjectiveThe present study aimed to investigate whether different preoperative left atrial appendage emptying speeds (LAAEVs) have an effect on left atrial function in patients with sinus arrhythmia after left atrial appendage closure (LAAC) combined with catheter ablation (CA).MethodsA total of 163 patients with persistent non-valvular atrial fibrillation who received combined LAAC+CA surgery were included in the present study. Regular follow-up was conducted for 12 months, and patients with complete data and successful sinus rhythm recovery were selected as the study subjects (n = 82). The patients were divided into two groups: the LAAEV < 25 cm/s group and the LAAEV ≥ 25 cm/s group (n = 41 each). The propensity score was used for matching according to gender, age, CHA2DS2-VASc score, and HAS-BLED score. The changes in the two groups in LA structure, storage function, conduit function, and pump function were compared.ResultsBefore surgery, the maximum LA volume (LAVmax) and minimum LA volume (LAVmin) were greater in the LAAEV < 25 cm/s group than in the LAAEV ≥ 25 cm/s group. The LA storage function (eg. Ƹ and SRs), conduit function (eg. SRe), and pump function (eg. SRa) were all worse in the LAAEV < 25 cm/s group than in the LAAEV ≥ 25 cm/s group. After the combined LAAC+CA surgery, the LA storage, conduit, and pump functions improved in both groups. At 12 months after surgery, there were no statistically significant differences between the two groups.ConclusionBefore combined LAAC+CA surgery, the LA structure and function of the LAAEV < 25 cm/s group were worse than those of the LAAEV ≥ 25 cm/s group. However, after LAAC+CA surgery, the LA structure and function of the patients were improved, and there were no significant differences between the two groups. Inferred improvement in LA structure and function in the LAAEV < 25 cm/s group was superior to that in the LAAEV ≥ 25 cm/s group.

Evaluation of atrial contractility and remodeling after the Maze-3 procedure with combined heart interventions

Highlights. The most important goal of atrial fibrillation surgical treatment is to eliminate the arrhythmia in order to restore atrial contractility and improve their transport function. Our study showed positive dynamics of atrial contractility and remodeling after the maze-3 procedure against the background of a regular heart rhythm restoration. The study of sinus rhythm predictors maintenance and recovery of atrial transport function will help to make patient selection more personified.Aim. Evaluation of atrial contractility and remodeling after the maze-3 procedure with combined interventions on the heart.Methods. The analysis of 217 combined surgical interventions was carried out, where a maze-3 was used to treat atrial fibrillation (AF). The operations were performed in our center from 2012 to 2016. Key points of the study: rhythm after surgery and echocardiographic control in the long-term follow-up in order to determine the dynamics of atrial contractility and volumes. The average follow-up period was 47 (1–100) months. 40 (18.4%) patients had paroxysmal, 38 (17.5%) persistent, 139 (64.1%) long-term persistent AF. The mean AF duration before surgery was 27.4 months (1–200 months). The indications for the maze-3 procedure were: ineffectiveness of antiarrhythmic therapy, the need to perform combined cardiac procedures. We used standard statistical research methods with one – and multivariate logistic regression.Results. In the long-term follow-up, sinus rhythm (SR) persists in 79% of patients. In the long-term follow-up, in this group of patients, the left atrial contractility was restored from 76% to 91%, while the biatrial contractility increased from 82 to 96%. Shorter AF duration before surgery was a positive predictor of SR recovery and atrial contractility (p = 0.005), while pulmonary artery pressure and patient age negatively affected these indicators (p = 0.041 and p = 0.038, respectively). The presence of SR early after surgery was not a significant predictor of AF freedom. At the same time, according to the long-term observations, patients maintaining a regular atrial heart rate had positive indicators of atrial systolic function restoration and a positive dynamics of a decrease in atrial volumes.Conclusion. SR and restoration of left atrial contractility are two interrelated goals of the maze procedure. The negative factors associated with the failure of surgical treatment of AF are increased pressure in the pulmonary artery, long-term AF before surgery, and the age of patients.

Does it make sense to study heart rate variability in episodes of paroxysmal atrial fibrillation during the 24-hour electrocardiographic monitoring?

Aim. To study the characteristics of heart rate variability (HRV) in episodes of paro xysmal atrial fibrillation (AF) and sinus rhythm (SR) during the 24-hour Holter electro cardiographic (ECG) monitoring and to assess the presence and nature of their relationships.Material and methods. We analyzed 37 records of 24-hour Holter ECG monitoring obtained from patients with paroxysmal AF. For analysis, records were selected from the Long Term Atrial Fibrillation database (LTAFDB) (n=26), as well as from the long-term storage database “Myocard-holter” of the Sverdlovsk Regional Clinical Hospital № 1 (n=11). Each record contained at least 120 min of SR and at least 120 min of paroxysmal AF episodes. In addition, 48 HRV indices were calculated independently for SR and for AF episodes, after which the 96 HRV parameters obtained for each record were subjected to exploratory data analysis.Results. Analysis of HRV in AF paroxysm showed a significant increase in the RMSSD, SD1, pNN50 indices, which confirmed the great importance of parasympathetic influence in the regulation of AF. Despite the fact that single HRV parameters in AF are not directly related to any single parameters in SR, we have shown that the AF is not completely chaotic and independent of the characteristics of baseline HR variability. We found that for some of the HRV indices determined during AF paroxysm (PAF_CVI, PAF_pNN20, PAF_pNN50, PAF_ApEn, PAF_SDNN, PAF_SD2), up to 74% of the variance of these indices can be explained using multivariate linear models, including 4 HRV indices for SR and taken as predictors. It was shown that among all the indices analyzed, only the PAF_HTI, calculated in paroxysmal AF, had a moderate negative correlation with the duration of AF episodes (r=0,60, p&lt;0,01).Conclusion. It is shown that the study of HRV indices on AF paroxysm has a wide clinical and electrophysiological potential. The paper proposes statistical models that demonstrate the relationship between HRV in SR and in the rhythm of AF episode. The PAF_HTI index, assessed on episodes of AF, showed a relationship with the duration of AF episodes, which suggests the expediency of using HRV characteristics on AF to assess the possibility of SR recovery.

P186 PROLONGED ASYSTOLIA REQUIRING CRP ON THERAPY WITH TICAGRELOR AND CYCLOSPORINE

Abstract 64–year–old man, from SriLanka, affected by arterial hypertension, complicated diabetes mellitus (retinopathy, vasculopathy, peripheral neuropathy) and chronic kidney injury in hemodialysis. Liver transplantation for hepatocarcinoma due to alcholic cirrhosis required cyclosporine as immunosuppressive agent. He also suffered from chronic multifactorial anemia and mild thrombocytopenia. Home therapy included atenolol 50mg, clonidine, lercanidipine, insulin, kayexalate, cyclosporine. He was admitted in ED for a chest pain during hemodialysis, associated with high blood pressure values and lateral ST–depression on ECG. Iv nitroglycerin relieved symtoms and normalized the repolarization. Echocardiogram showed a concentric ventricular hypertrophy, without wall motion changes or significant valvulopathy. Laboratory tests detected the known anemia, thrombocytopenia (Hb 9.6g/dl, PLT 100x109/L) and renal injury (creat 10mg/dl, K + 5.1mmol/L) with a stable rise of troponin T hs 80pg/ml (n.v.&amp;lt;14). Aspirin and ticagrelor 180mg were administered and Patient admitted for unstable angina. Coronary angiography (femoral approach) was performed and revealed a critical stenosis of proximal IVA with subocclusion of diagonal branch; no other significant lesion was detected. Coronary artery disease was effectively treated by PCI with 2 DES. During the 2nd day of hospitalization an asystolia up to 10” occurred and atenolol was stopped. The next day, he had a new diurnal sinus arrest, lasting about 40”; external pacing had no efficacy. After CPR, he had a ROSC with recovery of sinus rhythm. No electrolyte alteration or ischemic recurrences. Aminophylline was started and ticagrelor was suspended for possible side effect enhanced by interaction with cyclosporine; shift to clopidogrel was made. No recurrence of rhythm alteration occurred neither after aminophylline interruption at 72 hours nor after reintroduction of beta–blocker on the 8th day for sinus tachycardia. Cyclosporinemia was mildly elevated. It’s known that ticagrelor is associated with a higher incidence of bradyarrhythmias mediated by increase in adenosine concentration, but these are mainly asymptomatic and nocturnal. Cyclosporine– ticagrelor interaction, through inhibition of cytochrome P450 (CYP3A4) and P–gp, increased the concentration of ticagrelor and promoted its side effect: in our case prolonged episodes of asystolia requiring CPR, solved by drug withdrawal and aminophylline with target on adenosine receptors.

ПОШУКОВЕ ДОСЛІДЖЕННЯ ПРЕДИКТОРІВ ПІЗНІХ РЕЦИДИВІВ АРИТМІЇ У ПАЦІЄНТІВ З ПЕРСИСТУЮЧОЮ ФІБРИЛЯЦІЄЮ ПЕРЕДСЕРДЬ ПІСЛЯ КАРДІОВЕРСІЇ

Introduction. The existing guidelines do not contain a clear algorithm for predicting the late recurrences of atrial fibrillation (AFib). Objectives. We have studied the predictors of late recurrence of arrhythmia in patients with persistent AFib after the restoration of sinus rhythm (SR). Research methods. A prospective single-center study included 120 hospitalized patients with persistent AFib who underwent successful cardioversion. The recurrence of AFib was assessed in the early period after cardioversion by recording 12-channel ECG, Holter ECG monitoring and event ECG monitoring. After a nine-month period follow-up visit was performed. Baseline demographic, clinical-functional features and comorbidities were compared in group with (n = 87) and without (n = 33) late recurrences of Afib. Results. There were no differences in demographic, anthropometric data and comorbidities. Patients with late recurrence of AFib had a lower heart rate (HR) after SR recovery (p &lt;0.001). Early recurrences of AFib were found in 43 (49.4%) patients with late recurrences of arrhythmia and only in two (6.0%) without late recurrences (p &lt;0.001). Patients with late recurrences of arrhythmia had a lower average daily HR (p &lt;0.001), a higher number of single atrial extrasystoles (p = 0.001), atrial pairs and runs (p = 0.01) recorded by Holter ECG monitoring. Conclusions. Late recurrences of arrhythmia during the nine-month follow-up period were reported in 72.5% of patients. Groups of patients with and without late recurrence of arrhythmia had significant differences in the incidence of early recurrences, mean HR on SR, and the presence of atrial extrasystoles after rhythm recovery.

Short-term outcome of adenosine-lidocaine-magnesium polarizing cardioplegia in humans.

Hyperkalaemic depolarized myocardial arrest is the cornerstone of myocardial protection, although some potassium-related cytotoxicity has been demonstrated. Polarized arrest has gained interest because of a reported better myocardial protection in preclinical studies. The goal of this study was to analyse the quality of myocardial protection and hospital outcome after normokalaemic adenosine-lidocaine-magnesium (ALM) blood polarizing cardioplegia, compared to hyperkalaemic blood Buckberg depolarizing cardioplegia, in elective routine adult cardiac surgery. One thousand consecutive elective adult cardiac patients [627 undergoing ALM-polarizing cardioplegia (ALM-POL) vs 373 Buckberg depolarized cardioplegia (BUCK-DEPOL)] who were operated on were analysed. Perioperative leakage of high-sensitivity troponin I (Hs-TnI), peripheral lactate, inotropic and vasoactive daily requirement [maximal vasoactive inotropic score (VISMAX)], hospital mortality and morbidity were collected and compared in the overall population and in the propensity score (PS) matched population (206 pairs). A significantly lower leakage of Hs-TnI during hospitalization was detected in patients receiving ALM-POL versus those receiving BUCK-DEPOL (group time P < 0.001 for overall population and PS matched pairs). The maximum value of postoperative Hs-TnI was also lower after ALM-POL (P < 0.001 in both cohorts), and spontaneous recovery of sinus rhythm at aortic declamping was higher (P < 0.001 in favour of ALM-POL). Maximal VISMAX during hospitalization was significantly higher after BUCK-DEPOL in both cohorts (P = 0.019 for overall population; P = 0.031 for PS matched population), with significantly higher VISMAX on the day of surgery in BUCK-DEPOL PS matched patients (P = 0.042). No other significant differences in hospital morbidity and mortality were found. Despite comparable short-term clinical outcomes, ALM-POL cardioplegia proved superior in terms of quality of myocardial protection compared to BUCK-DEPOL cardioplegia in elective routine adult cardiac surgery.