Idiopathic Premature Ventricular Contractions Research Articles

Can the efficacy of a medical treatment be predicted based on the type of idiopathic premature ventricular contraction?

BackgroundPremature ventricular contractions (PVCs) are common arrhythmias with diverse clinical implications. This retrospective study aimed to evaluate the efficacy of medical treatments using various clinical, imaging, and electrocardiographic parameters in patients with idiopathic PVCs. MethodsA total of 1051 patients with idiopathic PVCs were retrospectively analyzed. Patients were categorized into three groups based on treatment response: beta-blocker (BB) responders (479 patients), calcium-channel blocker (CCB) responders (335 patients), and class 1c antiarrhythmic (AA) responders (237 patients). Clinical, imaging, and electrocardiographic data were collected and analyzed to assess the factors influencing treatment response. ResultsAge, left ventricular ejection fraction (LVEF), PVC QRS duration, CI variability, and multiple PVC morphologies were identified as significant factors affecting treatment response. Older age and lower LVEF were associated with better response to BB treatment, whereas CCB responders showed narrower QRS complexes. BB responders also exhibited higher CI variability, possibly linked to automaticity mechanisms. Moreover, the BB responder group had a higher frequency of multiple PVC morphologies. ConclusionThese findings emphasize the importance of tailored treatment approaches based on individual patient characteristics.

Focal monopolar pulsed field ablation from within the great cardiac vein for idiopathic premature ventricular contractions after failed radiofrequency ablation

BackgroundIdiopathic epicardial premature ventricular contractions (PVCs) originating from the left ventricular summit are difficult to eliminate. ObjectiveThe purpose of this study was to describe the feasibility and procedural safety of monopolar biphasic focal pulsed field ablation (F-PFA) from within the great cardiac vein (GCV) for treatment of idiopathic epicardial PVCs. MethodsIn 4 pigs, F-PFA (Centauri, CardioFocus) was applied from within the GCV followed by macroscopic gross analysis. In 4 patients with previously failed radiofrequency ablation, electroanatomic mapping was used to guide F-PFA from within the GCV and the ventricular outflow tracts. Coronary angiography and optical coherence tomography (OCT) were performed in 2 patients. ResultsIn pigs, F-PFA from within the GCV (5 mm away from the coronary arteries) resulted in myocardial lesions with a maximal depth of 4 mm, which was associated with nonobstructive transient coronary spasms. In patients, sequential delivery of F-PFA in the ventricular outflow tracts and from within the GCV eliminated the PVCs. During F-PFA delivery from within the GCV with prophylactic nitroglycerin application, coronary angiography showed no coronary spasm when F-PFA was delivered >5 mm away from the coronary artery and a transient coronary spasm without changes in a subsequent OCT, when F-PFA was delivered directly on the coronary artery. Intracardiac echocardiography and computed tomography integration was used to monitor F-PFA delivery from within the GCV. There were no immediate or short-term complications. ConclusionSequential mapping-guided F-PFA from endocardial ventricular outflow tracts and from within the GCV is feasible with a favorable procedural safety profile for treatment of epicardial PVCs.

Automated template matching versus conventional pace-mapping during pvc ablation: results from a randomized controlled trial

Abstract Background Pace-mapping has an important role in the ablation of idiopathic premature ventricular contractions (PVC). There is a software with an automated algorithm annotating and visualizing template matching points. Automated template matching (ATM) facilitates the matching process and may thus shorten the procedure duration and potentially increase ablation success. In this randomized study we evaluate whether the use of the automated template matching (ATM) software compared to conventional pace-mapping (PM) influences outcomes and periprocedural parameters in patients undergoing PVC ablation. Methods The study was performed as a prospective randomized controlled single-center clinical trial. Patients scheduled for de-novo PVC ablation were included and randomly assigned to either PVC ablation using the ATM algorithm (ATM) or conventional pace-mapping (PM). The primary endpoint was the procedural outcome represented by the PVC burden after three and twelve months. Secondary endpoints were periprocedural parameters including procedure duration, number, and duration of radiofrequency application (RFA), fluoroscopy (FS) dose, and duration. An interim analysis was predetermined after 72 patients had completed their three-month follow-up. Results After the interim analysis, the study was prematurely ended for futility. At termination of the trial 108 patients had been included. 18 patients dropped out of the study. Out of the remaining 90 patients, 88 patients (97%) have completed the three-month follow-up, and 73 patients (81%) the twelve-month follow-up. The mean age at the time of procedure was 57.3 years [18-82] without significant differences between both groups. Before ablation, the mean PVC burden was 20.8% [0.1-55.0] (ATM: 20.8% [3.0-55.9]; PM: 20.7% [0.1-44.0]; p=0.959). At 3-month follow-up, the mean PVC burden in both groups (ATM: 4.7% [0-29.4]; PM: 3.6% [0-45.7]; p=0.512) showed no significant difference between the groups. At 12-month follow-up the mean PVC burden in both groups (ATM: 3.8% [0-31]; PM: 2.2% [0-25.6]; p=0.282) also resulted in a non-significant difference between the groups. Furthermore, the procedural parameters (table) did not differ significantly between both groups. Conclusion In this randomized trial, the use of the automated template matching software did not result in improved outcomes or procedure-related parameters. Conventional pace-mapping appeared to be equally effective compared to the automated template matching software as used in this study.Table secondary endpoints

Recording of chest leads via mobile ECG and quantitative correlation with Wilson leads in a patient with monomorphic PVCs

Abstract Introduction Mobile ECGs using handy smartphone-based devices such as the KardiaMobile (AliveCor) are increasingly used as diagnostic tool for arrhythmias. They can be especially useful in cases of non-permanent arrhythmia. However, they were designed to record limb leads and few experience exists with the recording of modified chest leads. However chest leads provide important diagnostic information in many forms of arrhythmias including premature ventricular contractions (PVCs). We hypothesized that chest lead recordings using the 6-lead enabled KardiaMobile 6L device in a novel way would closely resemble the Wilson chest leads. Methods A patient with monomorphic idiopathic PVCs was identified. A standard 12- lead ECG was then taken in a supine position, and the exact same electrode positions were then used to record a mobile ECG in the supine position in the following manner: right finger and left finger positioned at the right and left sensor of the KardiaMobile 6L device respectively; back sensor positioned on the chest wall at the former positions of the chest electrodes, in a sequential manner (figure 1). The QRS morphologies of the 12-lead ECG Wilson leads and the reconstructed chest-leads with the mobile device were then overlied using Adobe illustrator and photoshop. The 12-lead ECG was also compared to a second 12-lead ECG of the patient that had been taken on the day before. Results QRS-morphologies of the chest leads derived from the 12-lead ECG and mobile ECG device resembled closely considering both regularly conducted beats and PVCs (figure 2 left and middle ECGs). Transition scores (TZ) of the sinus beats (3,5) and the PVCs (4) were identical. Overlaying two representative QRS-complexes of leads V1-6 of the Wilson leads and the mobile tracings showed a mean correlation of 73% for sinus beats and 78% for PVCs. In comparison, correlation of the QRS-complexes between the two 12-lead ECGs taken on consecutive days was 60% and 68% respectively (figure 2 left and right ECGs). Conclusion QRS-morphologies of the chest-leads taken with the KardiaMobile closely resembled the Wilson leads of the 12-lead ECG, and correlated better than did another 12-lead ECG that was taken the day before. The techniques could be useful for self-recording of arrhythmias including PVCs by patients to guide clinical decision-making in cases where no 12-lead ECG can be achieved due to intermittent arrhythmia occurrence.

Cognitive Behavioral Therapy for Symptom Preoccupation Among Patients With Premature Ventricular Contractions: Nonrandomized Pretest-Posttest Study.

Premature ventricular contractions (PVCs) are a common cardiac condition often associated with disabling symptoms and impaired quality of life (QoL). Current treatment strategies have limited effectiveness in reducing symptoms and restoring QoL for patients with PVCs. Symptom preoccupation, involving cardiac-related fear, hypervigilance, and avoidance behavior, is associated with disability in other cardiac conditions and can be effectively targeted by cognitive behavioral therapy (CBT). The aim of this study was to evaluate the effect of a PVC-specific CBT protocol targeting symptom preoccupation in patients with symptomatic idiopathic PVCs. Nineteen patients diagnosed with symptomatic idiopathic PVCs and symptom preoccupation underwent PVC-specific CBT over 10 weeks. The treatment was delivered by a licensed psychologist via videoconference in conjunction with online text-based information and homework assignments. The main components of the treatment were exposure to cardiac-related symptoms and reducing cardiac-related avoidance and control behavior. Self-rated measures were collected at baseline, post treatment, and at 3- and 6-month follow-ups. The primary outcome was PVC-specific QoL at posttreatment assessment measured with a PVC-adapted version of the Atrial Fibrillation Effects on Quality of Life questionnaire. Secondary measures included symptom preoccupation measured with the Cardiac Anxiety Questionnaire. PVC burden was evaluated with 5-day continuous electrocardiogram recordings at baseline, post treatment, and 6-month follow-up. We observed large improvements in PVC-specific QoL (Cohen d=1.62, P<.001) and symptom preoccupation (Cohen d=1.73, P<.001) post treatment. These results were sustained at the 3- and 6-month follow-ups. PVC burden, as measured with 5-day continuous electrocardiogram, remained unchanged throughout follow-up. However, self-reported PVC symptoms were significantly lower at posttreatment assessment and at both the 3- and 6-month follow-ups. Reduction in symptom preoccupation had a statistically significant mediating effect of the intervention on PVC-specific QoL in an explorative mediation analysis. This uncontrolled pilot study shows preliminary promising results for PVC-specific CBT as a potentially effective treatment approach for patients with symptomatic idiopathic PVCs and symptom preoccupation. The substantial improvements in PVC-specific QoL and symptom preoccupation, along with the decreased self-reported PVC-related symptoms warrant further investigation in a larger randomized controlled trial. ClinicalTrials.gov NCT05087238; https://clinicaltrials.gov/study/NCT05087238.

Idiopathic Premature Ventricular Contraction Catheter Ablation, Sedentary Population vs. Athlete's Populations: Outcomes and Resumption of Sports Activity.

There are no investigations about the outcomes of idiopathic PVC catheter ablation (CA) in athletes compared to the sedentary population. We conducted a prospective single-centre observational study. The primary and secondary procedural outcomes were the post-ablation reduction of premature ventricular contractions (PVCs) in an athletes vs. non-athletes group and in agonist vs. leisure-time athletes. The third was the evaluation of the resumption of physical activity and the improvement of symptoms in agonist and leisure-time athletes. From January 2020 to October 2022 we enrolled 79 patients with RVOT/LVOT/fascicular PVC presumed origin. The median percentage of decrease between the pre-procedure and post-procedure Holter monitoring in the non-athletes group was 96 (IQR 68-98) and 98 in the athletes group (IQR 92-99) (p = 0.08). Considering the athletes, the median percentage of decrease in the number of PVCs was 98 (IQR 93-99) and 98 (IQR 87-99), respectively, in leisure-time and agonistic athletes (p = 0.42). Sixteen (70%) leisure time and seventeen (90%) agonist athletes (p = 0.24) have resumed physical activity 3 months after PVC CA; among agonistic athletes, 59% have resumed competitive physical activity. Many leisure-time (88%) and agonist (70%) athletes experienced an improvement in symptoms after ablation. PVC CA was effective and safe in both groups, reducing symptoms and allowing a quick and safe return to sports activities in athletes.

Effects of Premature Ventricular Complex Burden on Left Ventricular Global Longitudinal Strain in Patients without Structural Heart Disease.

Background: Evaluation of left ventricular (LV) function in patients with idiopathic premature ventricular contraction (PVC) with preserved LV ejection fraction (LVEF), especially in the subclinical stage, may be of great importance in terms of directing early treatment. Methods: A total of 122 patients, retrospectively recruited, were divided into three groups according to PVC burden: Group 1; 5% ≤ PVC < 10%, Group 2; 10% ≤ PVC < 15%, and Group 3; 15% ≤ PVC. Transthoracic echocardiography (TTE) was performed to evaluate LV parameters. Results: LV-GLS (Global longitudinal strain) was found to be significantly lower in groups 2 and 3 with high PVC burden (18.9% ± 1.4, 17.5% ± 2.1, 16.3% ± 1.3; p < 0.001, respectively). Correlation analysis revealed a positive and significant correlation between PVC burden and deterioration in LV-GLS (r: 0.536; p < 0.001). In addition, PVC burden was found to be an independent predictor of LV-GLS deterioration in multiple linear regression analysis (β: 0.525, p < 0.001). The ROC curve analysis demonstrated that a PVC burden cut-off value of 8.4% was associated with a LV-GLS deterioration greater than -18, with a specificity of 75.4% and a sensitivity of 75.4% (AUC: 0.81 [0.73-0.88] 95% CI; p < 0.001). Conclusions: PVC burden was an independent predictor of deterioration in LV-GLS. The presence of LV-GLS deterioration due to PVC burden emphasizes the necessity for closer patient monitoring, observation of the response to pharmacological treatment, and evaluation of early invasive treatment strategies in selected patient groups.

Efficacy of Propafenone for Treating Idiopathic Premature Ventricular Contractions in Children

Efficacy of Propafenone for Treating Idiopathic Premature Ventricular Contractions in Children

Retracted: Target Characteristics and Voltage Mapping of the Matrix in Idiopathic Premature Ventricular Contractions Originating from the Right Ventricular Outflow Tract.

[This retracts the article DOI: 10.1155/2021/5551325.].

Clinical Characteristics and Features of Idiopathic Premature Ventricular Contractions with an Enlarged Left Atrium in Patients Without Structural Heart Diseases

Background and aims: Idiopathic premature ventricular contractions (PVCs) may cause subtle changes in left atrium (LA) structure and function. Here, we investigated whether serum sodium, body mass index (BMI), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and other characteristics might be associated with LA in these patients. Methods: A total of 268 consecutive patients diagnosed with idiopathic PVCs were retrospectively analyzed. We assessed associations of enlarged LA and with the clinical features obtained from 24-hour Holter monitoring, electrocardiography and serum data in patients with PVCs. Results: Patients with an enlarged LA (n = 101), compared with a normal LA (n = 167), had significantly lower serum sodium (140.9 ± 3.0 mmol/L vs 141.7 ± 2.8 mmol/L; P = 0.022), higher BMI (24.5 ± 2.7 kg/m2 vs 21.7 ± 2.5 kg/m2; P &lt; 0.001), higher NT-proBNP [99.3 (193.6) pg/mL vs 77.8 (68.8) pg/mL; P &lt; 0.001] and lower average heart rates (73.0 ± 8.0 bpm vs 75.3 ± 7.6 bpm; P = 0.019). No significant differences were observed in P-wave dispersion, QRS duration, PVC coupling interval, pleomorphism, circadian rhythm, non-sustained ventricular tachycardia, serum potassium, serum magnesium, hypersensitive C-reactive protein, low-density lipoprotein cholesterol, symptoms and PVC duration. Conclusions: Beyond the burden of PVCs, attributes such as serum sodium, BMI, NT-proBNP and average heart beats may potentially correlate with LA enlargement in individuals with idiopathic PVCs.

Role of Cardiac Magnetic Resonance in the Assessment of Patients with Premature Ventricular Contractions: A Narrative Review.

Premature ventricular contractions (PVCs) are a common finding in clinical practice, requiring a full diagnostic work-up in order to exclude an underlying cardiomyopathy. Still, in a substantial proportion of patients, these investigations do not identify any substrate, and the PVCs are labelled as idiopathic. Cardiac magnetic resonance (CMR) has proven in the last decades as the method of choice for the exploration of patients with cardiomyopathies, since it can identify subtle changes in the myocardial tissue and help with risk stratification. In patients with idiopathic PVCs and a high PVC burden, several studies report the presence of late gadolinium enhancement (LGE) at CMR, which can offer additional diagnostic and prognostic benefits, as well as assistance in catheter ablation procedures, as the risk for adverse cardiac and risk for arrhythmic events events is higher compared to patients without scar. This paper focuses on the impact of the presence of LGE in patients with idiopathic PVCs, reviewing all the relevant studies published so far, including randomized controlled clinical trials, prospective or retrospective cohort studies, case series and case reports as well as systematic reviews.

The role of heart rate variability in predicting the response to beta blocker in patients with frequent premature ventricular contractions

Abstract Background Frequent premature ventricular contractions (PVCs) in patients with structurally normal heart are not uncommon. Beta blocker is generally used to reduce symptom and burden of PVCs, but the response to beta blockers vary from patient to patient. Purpose This study aimed to investigate whether the heart rate variability (HRV) values could predict the response to beta blockers in patients with frequent PVCs. Methods We analyzed the patients who underwent 24-hour Holter monitoring and had PVC burden &amp;gt;3% in baseline 24-hour Holter monitoring. Bisoprolol and nebivolol was used to reduce symptom and burden of PVCs. The response to beta blocker was defined as the reduction of PVCs burden more than 50% in follow-up Holter monitoring. Baseline HRV was measured by time domain and frequency domain methods using 24-hour Holter monitoring. Results A total of 125 patients (mean age, 52.1 ± 14.7 years; male, 38.3%) underwent repeated 24-hour Holter monitoring were finally analyzed. Mean follow-up duration between the Holter monitoring was 205 ± 200 days. Among 125 patients with frequent PVCs, 45 patients had response to beta blockers. The ratio of low-frequency (LF) and high-frequency (HF) was higher in response group than those with non-response to beta blocker (P=0.016). LF, HF, and other variables measured by time-domain method were not associated with response to beta blocker. Conclusion The HRV value, especially LF/HF ratio, could predict the response to beta blockers in patients with idiopathic frequent PVCs.

Number of ventricular premature beats and other causes of cardiomyopathy associated with arrhythmia: case reports

We report a case of two patients with frequent idiopathic premature ventricular contractions. One of them had more than 25% of ventricular contractions per day leading to fast development of cardiomyopathy and its complete regression upon ventricular arrhythmia elimination. The second one had from 40% to 73% of ventricular contractions per day including non-sustained and sustained ventricular tachycardia without any structural changes of the heart during 28 years of follow-up.

Differential Profiles of Cortisol, Components of Autonomic Nervous System, and Self-Rated Health in Premature Ventricular Contraction: An Observational Study of Three Circadian Types

Objective: Premature ventricular contraction (PVC) exhibits one of the three circadian patterns, namely fast-type, slow-type, and independent-type. This study aimed to investigate whether the cortisol-marker of hypothalamic-pituitary-adrenal axis, autonomic nervous system activity, and perceptive self-rated health are associated with the three PVC circadian types.Methods: This cross-sectional observational study recruited 65 idiopathic PVC subjects (23 fast-, 20 slow-, and 22 independent-type) as well as 5 control subjects. Each subject underwent a 24- hour Holter to examine PVC burden and heart rate variability, collected saliva for cortisol and norepinephrine level measurement at 6–7 am, 10–11 am, and 10–11 pm, and recorded their self-rated health scales. Furthermore, univariate and multiple linear regression were conducted to investigate the associations between the independent variables and PVC burden.Results: The average PVC burden was 15.7%, 8.5%, and 13.6% in fast-, slow-, and independent-type idiopathic PVCs, respectively. Multiple linear regression showed that the high burden of fast-type idiopathic PVC was associated with higher cortisol levels and lower parasympathetic nervous system tone. The high burden of slow-type idiopathic PVC was associated with lower cortisol levels and lower sympathetic nervous system tone. Meanwhile, in independent-type idiopathic PVC, the high burden was associated with higher cortisol levels and sympathetic nervous system tone as well as lower self-rated health scales.Conclusion: Each PVC circadian type is uniquely related to hypothalamic-pituitary-adrenal axis, autonomic nervous system, and selfrated health. Assessment of PVC circadian type needs to be carried out routinely considering the differences in the underlying associated factors.

Lead I R-wave indexes: A novel electrocardiographic criterion for distinguishing the origin of idiopathic premature ventricular contractions from the three subregions of the aortic sinus cusps

PurposeThe current study was conducted to investigate the electrocardiographic (ECG) characteristics of idiopathic premature ventricular contractions (PVCs) originating from the aortic sinus cusp (ASC) and establish a novel ECG criterion to discriminate PVCs originating from the right coronary cusp (RCC), left coronary cusp (LCC), and the left and right coronary cusp junction (LRJ). MethodsA retrospective analysis was performed on a total of 133 patients with idiopathic PVCs who underwent successful mapping and ablation. The sites of origin (SOO) were confirmed using fluoroscopy and a three-dimensional mapping system during radiofrequency catheter ablation (RFCA). Among the patients, 69 had PVCs originating from the LCC, 39 from the RCC, and 25 from the LRJ. Characteristics of surface 12‑lead electrocardiograms (ECGs) recorded during PVCs were analyzed. Q-, R-, S, and R'-wave amplitudes were measured in lead I, and the lead I R-wave indexes (IRa, IRb, IRc, IRd, and IRe) were derived by employing multiplication, subtraction, sum, and division operations on these ECG measurements. Notably, IRb and IRe demonstrated usefulness as ECG indexes for discriminating PVCs originating from RCC, LCC, and LRJ in the ASC. ResultsThe R- and S-wave amplitudes in lead I exhibited statistically significant differences among the three groups (P < 0.001 and P < 0.001, respectively). In discriminating PVCs originating from the RCC from the other two groups, IRb showed the largest area under the curve (AUC) of 0.813, as assessed by receiver operating characteristic (ROC) analysis, with a cutoff value of ≤0.5 indicating PVCs of RCC origin. The sensitivity and specificity were 80.3% and 78.7%, respectively. For discriminating PVCs arising from the LCC from those in the LRJ group, IRe exhibited the largest AUC of 0.801, with an optimal cutoff value of 0. An IRe value >0 indicated PVCs originating from the LRJ, while an IRe value ≤0 indicated PVCs originating from the LCC. The sensitivity and specificity of the IRe index were 84.0% and 70.7%, respectively. ConclusionLead I R-wave indexes provided simple and useful ECG criteria for discriminating PVCs originating from the LCC, RCC, and LRJ in the left ventricular outflow tract (LVOT).

Efficacy of Radiofrequency Catheter Ablation versus Antiarrhythmic Drugs in Treating High Burden Premature Ventricular Contractions in Children with Structurally Normal Heart

Abstract Background Scarce literature on whether antiarrhythmic drugs (AADs) or radiofrequency catheter ablation (RFCA) is more efficacious when treating idiopathic high burden premature ventricular contractions (PVCs) in children with many questions remain unanswered in this age group. Objectives To compare the efficacy of RFCA versus AADs on high burden idiopathic PVCs in children. Methods A total of 60 eligible child ≤18 years with High burden PVCs (≥10% of total beats per day) that were treated by either AADs (group A) or RFCA (group B). Both Baseline and followup clinical symptoms were collected, Physical examination, repeat standard ECG, standard or 12-lead Holter recording, and echocardiography were performed. Results Among RFCA (n = 30) and AADs (n = 30) groups, treatment success was 80.0% and 20.0% respectively, while AADs medications cessation was 73.3% and 26.7% respectively, the differences were statistically significant. Conclusion RFCA appears to be more efficacious than AADs in PVC reduction and consequently AADs medications cessation postablation. Performing RFCA in children with classical mapping and navigation was a safe and highly effective therapeutic option. Abbreviations AADs: antiarrhythmic drugs; BBB: bundle branch block; CCB: calcium channel blocker; ECG: electrocardiogram; LVEDD: left ventricular end-diastolic dimension; LVEF: left ventricular ejection fraction; LVESD: left ventricular end-systolic dimension; LVOT: left ventricular outflow tract; NSVT: non sustained ventricular tachycardia; PVC: premature ventricular contraction; RFCA: radiofrequency catheter ablation; RV: right ventricular/ventricle; RVOT: right ventricular outflow tract

Prediction of ablation success of idiopathic premature ventricular contractions with an inferior axis using the twelve-lead electrocardiogram

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Catheter ablation is the first line treatment for idiopathic premature ventricular contractions (PVCs) from the right ventricular outflow tract (RVOT) but not left ventricular outflow tract (LVOT). However, differentiating the two using the twelve-lead electrocardiogram (ECG) is challenging. As an alternative strategy to guide clinical decision-making, we sought to find ECG criteria that predict outcome of catheter ablation directly rather than focus only. Methods This observational single center study included patients undergoing an ablation procedure for idiopathic PVCs with an inferior axis (positive QRS in leads II, III and aVF) at Hannover Heart Rhythm Center between 2012 and 2020. Patients were excluded if no activation mapping was performed because of low PVC activity. A complete suppression of the index PVC at the end of the ablation procedure was considered as ablation success. PVC axis was estimated with the help of the hexaxial reference system, and as an objective control was also calculated measuring QRS voltages and using three formulas: Arctan (aVF/I), Arctan ((2*II-I)/(Sqr(3)*I)) and +/-Arctan ((2*aVF)/(Sqr(3)*I)). Results The analysis included 108 patients (53% male, age 53 ± 17 years) with a PVC count of 22063 ± 14426 /24h. The dominant PVC had Left Bundle Branch Block (LBBB) like morphology in 80%, a mean transition (TZ)-score of 2.3 ± 1.2 and a mean axis of 87 ± 15°, estimated with the help of the hexaxial system. There was no significant difference between axis as estimated with the help of the hexaxial system compared to calculation via any of the formulas (87 ± 14, 87 ± 12 and 86 ± 16°, respectively). Overall ablation success was 82%. Considering ablation outcome according to the identified PVC localization, 46 of 47 cases (97.9%) of RVOT focus and 38 of 39 cases (97.4%) of LVOT focus were successful. On the other hand, all 8 cases with a parahisian focus were not successful and only 4 of 14 cases (28.6%) with a CS/LV summit focus were successful. Two ECG criteria were found to predict ablation failure: a more leftward PVC axis (p=0.015), which was associated with a parahisian focus (p&amp;lt;0.001), and an early precordial transition compared to the QRS complex during AV-nodal conduction (p=0.016), which was associated with a CS/LV summit focus (p&amp;lt;0.001). Using ROC statistics, a cutoff value of 75° for PVC axis and of 2.75 for TZ-Score index predicted ablation success with a positive predictive value of 93% if neither parameter applied (prediction of ablation failure, if either applied, 53 %). Conclusion Two ECG criteria – a more leftward PVC axis and an early precordial transition compared to sinus rhythm – predicted ablation failure and a parahisian or CS/LV summit focus. These parameters should be considered when evaluating a patient for catheter ablation of PVCs with an inferior axis.

Similarly high success and low complication rates of catheter ablation for idiopathic premature ventricular contractions from the left and right ventricular outflow tract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Catheter ablation is the first line treatment for idiopathic premature ventricular contractions (PVCs) from the right ventricular outflow tract (RVOT) but not from the left ventricular outflow tract (LVOT), due to presumed lower success and higher complication rates in the LVOT. In this observational single center study we analyzed success rates and complication rates in patients undergoing catheter ablation for idiopathic PVCs with an inferior axis. Methods Patients undergoing catheter ablation for idiopathic PVCs with an inferior axis at Hannover Heart Rhythm Center between 2012 and 2020 were included. Patients were excluded if no activation mapping could be performed because of low PVC activity. Ablation success was defined as complete suppression of the index PVC at the end of the procedure. Results 108 patients (53% male, age 53 ± 17 years) with predominantly symptomatic (94%) PVCs with one (72%), two (20%) or more (8%) morphologies and a PVC count of 22063 ± 14426 /24h were included. 47 PVCs (44%) were located in the RVOT (21 anterior RVOT and 26 septal RVOT) and 39 PVCs (36%) in the LVOT (11 lateral LVOT, 5 septal LVOT, 8 RCC, 2 ACC, 13 LCC). 14 PVCs (13%) had the origin close to the CS/LV summit and 8 PVCs (7%) in the parahisian region. Overall success rate was 82%. Success rates for RVOT and LVOT origin were 98% (46/47 cases) and 97% (38/39 cases) respectively. No significant differences in procedure time (145 ± 68 vs. 158 ± 72 min), ablation time (441 ± 328 vs. 462 ± 307 sec), fluoroscopy time (496 ± 521 vs. 519 ± 473 sec) or minor complications (5 vs. 8) were observed for outflow tract PVCs, and no major complications occurred in this group. However, 3 major complications and significantly lower success rates were observed for non-outflow tract PVCs (0/8 for parahisian origin, 4/14 (29%) for CS/LV summit origin). 2 patients with a parahisian focus experienced higher degree AV block and 1 patient with an LV summit focus had a pericardial tamponade. Conclusion Catheter ablation of PVCs with LVOT origin can be performed with similarly high success and low complication rates compared to PVCs with RVOT origin, and therefore could be considered as first-line therapy like RVOT PVCs. On the other hand, identification of PVCs with a parahisian or CS/LV summit focus should be aspired before an ablation procedure, as these localizations are associated with poorer ablation outcome and higher complication rates.

Impact of pacing output and cycle length on QRS morphology in ablation of premature ventricular contractions (PACE-MAP-trial)

Abstract Funding Acknowledgements Type of funding sources: None. Background Pace mapping is an established technique to localize the origin of premature ventricular contractions (PVC). The QRS morphology induced by endocardial pacing is compared with a previously recorded template of the target arrhythmia. Based upon historic in-vitro models pacing at the arrhythmia’s coupling interval (CI) and stimulation threshold has become the gold standard in pace mapping. Purpose There is a paucity of data supporting pacing at the CI and stimulation threshold as the gold standard for pace mapping. In this prospective study, we sought to assess systematically the impact of variations of pacing output and cycle length on the resulting QRS morphology during pace mapping in the context of PVC ablation. Methods All patients undergoing ablation of idiopathic PVC were prospectively enrolled in this study. Pace mapping was performed using four different parameter settings: (1) A predefined fixed burst at maximum output (10V/2ms), (2) fixed burst at stimulation threshold, (3) coupling interval at maximum output and (4) coupling interval at stimulation threshold. Pacing cycle length (PCL) of the fixed burst was defined as follows: For a CI≤450ms = PCL of CI+100ms and for a CI≥450 = PCL of CI-100ms. Using an automated waveform comparison algorithm (Bard® LabSystem™ PRO software; Boston Scientific, MA, USA), the resulting QRS complexes were matched with the clinical PVC, and with the gold standard. For every parameter setting the mean of the matching percentage of three QRS complexes entered the analysis. Results We report data of the first 47 consecutive patients (57±18 years, 64% male) enrolled in this ongoing study between May 2021 and September 2022. The pacing protocols were performed at 75 different sites: 6/75 epicardially via great cardiac vein, 38/75 in the RVOT, 23/75 in LVOT and 8/75 in the left ventricular cavity. When comparing the QRS morphologies resulting from the four different pace mapping settings with the clinical PVC, the univariate analysis revealed no difference between groups (p=0.9). Furthermore, there was no difference comparing the paced QRS morphologies at different output and cycle length to the gold standard of threshold pacing at coupling interval (p=0.9). Conclusion Variations of pacing output and stimulation cycle length during pace mapping does not affect QRS morphology during PVC ablation. Applying a modern automated waveform comparison tool, no advantage was observed when comparing with the gold standard. It is therefore reasonable to assume, that pace mapping can be performed using an easily applicable setting of a fixed burst at maximum pacing output.

59. Differential Profiles of Cortisol, Components of Autonomic Nervous System, and Self-Rated Health in Predicting Circadian Variability of Idiopathic Premature Ventricular Contraction Burden

ABSTRACT: Premature ventricular contraction (PVC) patients exhibit specific circadian patterns, yet the lack of circadian rhythm increases the risk of cardiomyopathy. To fully understand the three types of PVC circadian rhythms, we must therefore understand the mechanism of circadian variability, not just of PVC burden. Reflecting on 65 idiopathic PVC patients collecting saliva for cortisol and norepinephrine levels three times daily, undergoing a 24-hour Holter examination, and reporting their morning, afternoon, and evening self-rated health scales; this paper indicates pathways in which psycho-neuro-endocrine physiology and circadian variability in frequency of PVC burden are embodied. Higher cortisol levels and lower parasympathetic nervous system tone are at higher risk of higher burden of fast-type idiopathic PVC. Lower cortisol levels and lower sympathetic nervous system tone are at higher risk of higher burden of slow-type idiopathic PVC. Higher cortisol levels and sympathetic nervous system tone as well as lower self-rated health scales are at higher risk of higher burden of independent-type idiopathic PVC.