Symptomatic Premature Ventricular Contractions Research Articles

Use of class IC antiarrhythmic drugs in patients with structural heart disease and implantable cardioverter defibrillator

Abstract Background Due to suspected pro-arrhythmic effects and increased mortality associated with class-IC antiarrhythmic drugs (AADs) in previous trials, AAD-therapy in structural heart disease (SHD) is mainly restricted to amiodarone. In the presence of diagnostic and therapeutic advancements in cardiovascular medicine, it remains unclear if previous studies adequately reflect contemporary patients. In clinical practice, class-IC-AADs are occasionally used in individual cases, particularly in patients with an implantable cardioverter defibrillator (ICD). Methods This study retrospectively investigated outcome in ICD-carriers with SHD in whom class-IC-AADs were used as an individualized therapy due to failure, side effects, or unacceptable risk of alternative therapeutic options. Results Fifty patients from four tertiary centers were included (median age 48.5 years; 52% female). The most common underlying SHD were dilated (42%) or ischemic cardiomyopathy (26%) (median LVEF=45%). Indications for AAD were sustained ventricular arrhythmias (VA) (58%), symptomatic premature ventricular contractions (26%), or atrial arrhythmias (16%). Median follow-up was 27.8 months. Freedom from sustained VA was 72%, freedom from ICD-therapy was 80%. In 19 patients (38%) AAD-therapy was terminated. The most common reason was insufficient efficacy (n=8). Pro-arrhythmia was suspected in three patients. Five patients died during follow-up (10.0%), two of cardiovascular cause (4.0%). Conclusion In a multicenter cohort of ICD-carriers with SHD, class-IC-AADs were associated with a low rate of pro-arrhythmic effects or cardiovascular mortality. The majority of patients remained free from sustained VA during a follow-up of >2 years. Further efforts should be made to evaluate the safety of class-IC-AADs in SHD-patients receiving contemporary cardiovascular therapy.

Bipolar catheter ablation of left ventricular summit PVC

Abstract Background Premature ventricular contractions (PVC) arising from the left ventricular summit are a challenging arrhythmia to manage, often refractory to conventional radiofrequency ablation. This study aimed to investigate the effectiveness of bipolar ablation as a therapeutic option for PVCs originating from this anatomically complex region. Methods We conducted a retrospective analysis of a prospective ablation registry to identify patients with recurrent, symptomatic PVCs originating from the left ventricular (LV) summit who underwent bipolar ablation. Bipolar ablation involved the use of two ablation catheters, delivering radiofrequency energy from opposite sides of the summit. The catheters were connected by a dedicated adapter, allowing to connect one ablation catheter in position of a return electrode. Procedural success was defined as the elimination of PVCs during the procedure and freedom from PVCs on follow-up monitoring. Results were compared to a similar patient group who had received unipolar ablation of summit-PVCs. Results A total of 12 pts received bipolar ablation between July 2022 and October 2023. Three pts underwent ablation for VT and were excluded. A total of 9 pts (mean age 57±18 years, n=7 [78%] male, BMI 28±5kg/m2) were included in the analysis. All but one had a history of a previous unsuccessful ablation attempt (median 1 [1-2]). In a group of 33 patients undergoing unipolar ablation 8 (32%) had received ≥ 1 previous ablation and were included in the analysis. Baseline parameters did not differ between groups. The acute procedural success rate for bipolar ablation was 89% in bipolar pts and 75% in unipolar pts, with a mean procedural time of 173±33 min, a mean fluoroscopy time of 14±9 min (158±55 min [p=0.478] and 14±12 min [p=0.995] for unipolar pts). Bipolar ablation was performed between the LVOT and RVOT in 6, and between LVOT and the distal CS in 6 pts with 25-35 W. No major complications were detected in bipolar pts while one non-fatal tamponade occurred in the unipolar pts group. Follow-up data at 97 [93-269] days revealed a sustained reduction in PVC burden in bipolar pts (from 18±13% to 7±9%; p=0.026) while unipolar ablation did not show a significant burden reduction (15±6% to 11±10%; p=0.382). The success rate of a relative burden reduction >50% did not differ significantly between the groups (bipolar: 6 pts [67%] 3 pts [38%]; p=0.347). Conclusion Bipolar ablation offers an effective and safe therapeutic approach for PVCs originating from the LV summit. It significantly reduced PVC burden in this analysis. The data suggest that a repeat procedure after a failed summit PVC ablation should only be performed if bipolar ablation is available during the second procedure. Larger studies are warranted to confirm efficacy and safety of this ablation method.

Use of class IC antiarrhythmic drugs in patients with structural heart disease and implantable cardioverter defibrillator.

Due to suspected pro-arrhythmic effects and increased mortality associated with class-IC antiarrhythmic drugs (AADs) in previous trials, AAD therapy in structural heart disease (SHD) is mainly restricted to amiodarone. In the presence of diagnostic and therapeutic advancements in cardiovascular medicine, it remains unclear if previous studies adequately reflect contemporary patients. In clinical practice, class-IC-AADs are occasionally used in individual cases, particularly in patients with an implantable cardioverter defibrillator (ICD). This study retrospectively investigated outcome in ICD-carriers with SHD in whom class-IC-AADs were used as an individualized therapy due to failure, side effects, or unacceptable risk of alternative therapeutic options. Fifty patients from four tertiary centers were included (median age 48.5years; 52% female). The most common underlying SHD were dilated (42%) or ischemic cardiomyopathy (26%) (median LVEF = 45%). Indications for AAD were sustained ventricular arrhythmias (VA) (58%), symptomatic premature ventricular contractions (26%), or atrial arrhythmias (16%). Median follow-up was 27.8months. Freedom from sustained VA was 72%, and freedom from ICD therapy was 80%. In 19 patients (38%), AAD therapy was terminated. The most common reason was insufficient efficacy (n = 8). Pro-arrhythmia was suspected in three patients. Five patients died during follow-up (10.0%), two of cardiovascular cause (4.0%). In a multicenter cohort of ICD-carriers with SHD, class-IC-AADs were associated with a low rate of pro-arrhythmic effects or cardiovascular mortality. The majority of patients remained free from sustained VA during a follow-up of > 2years. Further efforts should be made to evaluate the safety of class-IC-AADs in SHD patients receiving contemporary cardiovascular therapy.

PO-05-097 FIRST REPORT OF CRYOABLATION OF NON-PAPILLARY MUSCLE PVCS UNDER DIRECT VISUALIZATION DURING MV REPAIR: INTER-LEAFLET TRIANGLE AND THE AORTO-MITRAL CONTINUITY

Up to 60% of patients with mitral valve prolapse (MVP) have premature ventricular contractions (PVC), usually of papillary muscle (PM) origin. However, one-third of PVCs are of non-PM origin, from areas exposed to annular stress forces. We have previously demonstrated the feasibility of intraoperative cryoablation of PM PVCs under direct visualization during mitral valve (MV) repair. To our knowledge, this is the first report of a similar approach for non-PM PVCs. We present two cases of visually-guided surgical cryoablation of non-PM PVCs at the time of elective MV repair. Both were guided by ECG morphology criteria and hybrid PET/MRI imaging pre-operatively. n/a Case 1 (Figure): 73 year old female with degenerative MVP, severe MR and frequent PVCs (27%). There were two PVC morphologies: the dominant PVC was suggestive of interleaflet triangle (ILT) origin (abrupt V3 transition), and the less frequent PVC was consistent with postero-medial PM origin. Hybrid PET-MRI demonstrated focal uptake of FDG in the LV summit region just under the aortic valve. The patient underwent an uncomplicated MV repair, TV repair and cryoablation of the ILT (open endocardial retrograde approach) and then the posterior PM. Follow up TTE showed normal MV and aortic leaflets function without regurgitation or stenosis. An event monitor at 2 months post-op revealed a PVC burden of 2% (off drugs). Case 2: 76 year old male with degenerative MVP, severe mitral regurgitation (MR) and frequent symptomatic PVCs (24%), suggestive of an aortomitral continuity (AMC) origin. Simultaneous cardiac 18F FDG-PET and MRI with LGE imaging demonstrated focal uptake of FDG in the AMC region, no LGE was detected. The patient underwent an uncomplicated MV repair, TV repair and cryoablation of the AMC. The cryo-application was performed on the atrial side of the mitral annulus with forward pressure to reach the ventricular myocardium. There were no PVCs during post-op monitoring and a 6-month follow-up monitor revealed a PVC burden of 1% (off drugs). Surgical cryoablation of non-PM PVCs under direct visualization at the time of MV surgery, using standard ECG criteria and pre-op Hybrid PET-MRI imaging, is feasible. Further studies are needed to determine the safety and effectiveness of adjunctive PVC cryoablation at the time of MV surgery.

Asymptomatische ventrikuläre Extrasystolen behandeln?

Premature ventricular contractions (PVC) are acommon arrhythmia. Therapy is indicated in case of frequent symptomatic PVC or deterioration of left ventricular function. Asymptomatic patients should be evaluated critically for possible PVC-associated symptoms. Catheter ablation of PVCs in patients with normal left ventricular ejection fraction (LVEF) is safe and effective. PVC-induced cardiomyopathy should be considered in unexplained LVEF dysfunction with aPVC burden of at least 10%. If ECG and echocardiography do not clearly rule out structural heart disease (SHD) or the clinical presentation raises suspicion of SHD, cardiac magnetic resonance imaging should be performed. If SHD has been excluded, the guidelines recommend catheter ablation as primary therapy in frequent monomorphic PVC, regardless of symptoms. To prevent PVC-induced cardiomyopathy, ablation can also be considered in asymptomatic patients with aPVC burden > 20%. Also, in patients with known SHD frequent PVC can aggravate LV dysfunction and catheter ablation should be considered.

Abstract 12000: Ventricular Arrhythmias and Sudden Death Events Following Acalabrutinib Therapy Initiation for Hematology Malignancies

Introduction: Acalabrutinib, a next generation Bruton’s tyrosine kinase inhibitor (BTKi) associates with dramatic efficacy against hematology malignancies. Unexplained ventricular arrhythmias (VAs) with next generation BTKi therapy have been reported. Yet, whether acalabrutinib associates with VAs in long-term follow up is unknown. Methods: Leveraging a cohort of 290 consecutive hematologic malignancy patients treated with acalabrutinib (2014-2020), we assessed VA incidence. The primary endpoint was incident VA development (ventricular fibrillation, ventricular tachycardia, and symptomatic premature ventricular contractions). Probability Scores determined likelihood of acalabrutinib association. Incident rates as function of time on therapy were calculated. Weighted average incidence rates were compared to observed rates in a large contemporary similar aged general population using relative risk. Absolute excess risk (AER) for acalabrutinib associated VAs was estimated. Results: Over 1,063 person years of follow up, there were 8 incident VA cases, including 6 in those without coronary disease (CAD) or heart failure (HF), and 1 sudden death; median time to event was 14.9 months. Among those without prior ibrutinib use, CAD, or HF, weighted average incidence was 394 per 100,000 person years. This compares to 596 for ibrutinib related VAs (RR 0.66, P<0.01; figure) and 48.1 among similar aged non-BTKi treated subjects (RR 8.2, P<0.001; AER 346). Outside of age, no cardiac or electrocardiographic variables associated with VA development . Conclusions: Acalabrutinib associates with increased risk of incident VAs. Collectively, these data suggest VAs may be a class effect of BTKi therapies. Figure: Ventricular arrhythmia (VA) crude (A) and cumulative (B) incidence rates in acalabrutinib users versus ibrutinib and non BTKi treated populations. *Those without prior ibrutinib use or structural heart disease. **Assumes linear a event rate over time.

Ventricular arrhythmias and sudden death events following acalabrutinib initiation

AbstractAcalabrutinib, a next-generation Bruton’s tyrosine kinase inhibitor (BTKi), associates with dramatic efficacy against B-cell malignancies. Recently, unexplained ventricular arrhythmias (VAs) with next-generation BTKi-therapy have been reported. Yet, whether acalabrutinib associates with VAs in long-term follow-up is unknown. Leveraging a large-cohort of 290 consecutive B-cell malignancy patients treated with acalabrutinib from 2014 to 2020, we assessed the incidence of VAs. The primary-endpoint was incident VA development (ventricular fibrillation, ventricular tachycardia, and symptomatic premature ventricular contractions). Probability-scores were assessed to determine likelihood of acalabrutinib-association. Incident rates as function of time-on-therapy were calculated. Weighted average observed incidence rates were compared with expected population rates using relative-risks. Absolute excess risk (AER) for acalabrutinib-associated VAs was estimated. Over 1063 person-years of follow-up, there were 8 cases of incident-VAs, including 6 in those without coronary disease (CAD) or heart failure (HF) and 1 sudden-death; median time-to-event 14.9 months. Among those without prior ibrutinib-use, CAD, or HF, the weighted average incidence was 394 per 100 000 person years compared with a reported incidence of 48.1 among similar-aged non–BTKi-treated subjects (relative risk, 8.2; P < .001; AER, 346). Outside of age, no cardiac or electrocardiographic variables associated with VA development. Collectively, these data suggest VAs may be a class-effect of BTKi therapies.

Speckle Tracking Versus Conventional Echocardiography in Patients with Symptomatic Premature Ventricular Contractions

Frequent premature ventricular complexes [PVCs] are linked to the left ventricular [LV] dysfunction. Early diagnosis is crucial for the proper treatment.

Impact of age on catheter ablation of premature ventricular contractions

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Catheter ablation (CA) of frequent premature ventricular contractions (PVC) is increasingly performed in older patients as the population ages. Purpose The purpose of this study was to assess the impact of age on procedural characteristics, safety and efficacy on PVC ablations. Methods Consecutive patients with symptomatic PVCs undergoing CA between 2015 and 2020 were evaluated. Acute ablation success was defined as the elimination of PVCs at the end of the procedure. Sustained success was defined as an elimination of symptoms, and ≥80% reduction of PVC burden determined by Holter-ECG during long-term follow. Patients were sub-grouped based on age (&amp;lt; 65 years vs. ≥ 65 years). Results A total of 114 patients were enrolled (median age 64 years, 71% males) and followed up for a median duration of 228 days. Baseline and procedural data were similar in both age groups. A left-sided origin of PVCs was more frequently observed in the elderly patient group compared to younger patients (83% vs. 67%, p = 0.04, Figure 1). The median procedure time was significantly shorter in elderly patients (160 min vs. 193 min, p = 0.02). The rates of both acute (86% vs. 92%, p = 0.32) and sustained success (70% vs. 71%, p = 0.90) were similar between groups. Complications rates (3.7%) did not differ between the two groups. Conclusion In a large series of patients with a variety of underlying arrhythmia substrates, similar rates of acute procedural success, complications, and ventricular arrhythmia-free-survival were observed after CA of PVCs. Older age alone should not be a reason to withhold CA of PVCs. Abstract Figure 1

Symptomatic Premature Ventricular Contractions in Vasovagal Syncope Patients: Autonomic Modulation and Catheter Ablation.

IntroductionThere has been limited reports about the comorbid premature ventricular contractions (PVCs) and vasovagal syncope (VVS). Deceleration capacity (DC) was demonstrated to be a quantitative evaluation to assess the cardiac vagal activity. This study sought to report the impact of autonomic modulation on symptomatic PVCs in VVS patients.Methods and ResultsTwenty-six VVS patients with symptomatic idiopathic PVCs were consecutively enrolled. Identification and catheter ablation of left atrial ganglionated plexi (GP) and PVCs were performed in 26 and 20 patients, respectively. Holter 24 h-electrocardiograms were performed before and after the procedure to evaluate DC and PVCs occurrence. Eighteen patients were subtyped as DC-dependent PVCs (D-PVCs) and eight as DC-independent PVCs groups (I-PVCs). In D-PVCs group, circadian rhythm of hourly PVCs was positively correlated with hourly DC (P < 0.05) while there was no correlation in I-PVCs group (P > 0.05). Fifty-three GPs with positive vagal response were successfully elicited (2.0 ± 0.8 per patient). PVCs failed to occur spontaneously nor to be induced in six patients. In the remaining 20 patients, PVCs foci identified were all located in the ventricular outflow tract region. Post-ablation DC decreased significantly from baseline (P < 0.05). During mean follow-up of 10.64 ± 6.84 months, syncope recurred in one patient and PVCs recurred in another. PVCs burden of the six patients in whom neither catheter ablation nor antiarrhythmic drugs were applied demonstrated a significant decrease during follow-up (P = 0.037).ConclusionAutonomic activities were involved in the occurrence of symptomatic idiopathic PVCs in some VVS patients. D-PVCs might be facilitated by increased vagal activities. Catheter ablation of GP and PVCs foci may be an effective, safe treatment in patients with concomitant VVS and idiopathic PVCs.

Impact of age on catheter ablation of premature ventricular contractions.

Catheter ablation (CA) of frequent premature ventricular contractions (PVC) is increasingly performed in older patients as the population ages. The aim of this study was to assess the impact of age on procedural characteristics, safety and efficacy on PVC ablations. Consecutive patients with symptomatic PVCs undergoing CA between 2015 and 2020 were evaluated. Acute ablation success was defined as the elimination of PVCs at the end of the procedure. Sustained success was defined as an elimination of symptoms, and ≥80% reduction of PVC burden determined by Holter-electrocardiogram during long-term follow. Patients were sub-grouped based on age (<65 vs. ≥65 years). A total of 114 patients were enrolled (median age 64 years, 71% males) and followed up for a median duration of 228 days. Baseline and procedural data were similar in both age groups. A left-sided origin of PVCs was more frequently observed in the elderly patient group compared to younger patients (83% vs. 67%; p = .04). The median procedure time was significantly shorter in elderly patients (160 vs. 193 min; p = .02). The rates of both acute (86% vs. 92%; p = .32) and sustained success (70% vs. 71%; p = .90) were similar between groups. Complications rates (3.7%) did not differ between the two groups. In a large series of patients with a variety of underlying arrhythmia substrates, similar rates of acute procedural success, complications, and ventricular arrhythmia-free-survival were observed after CA of PVCs. Older age alone should not be a reason to withhold CA of PVCs.

Vitmamin D supplementation with Cardiac Rehabilitation reduces the number of RVOT Premature

Introduction. Vitamin D deficiency is a quite common pathology in European countries. Serum vitamin D levels are closely linked to physical fitness and lesser response to cardiac rehabilitation in various categories of patients with heart disease. Vitamin D is also involved in the function of heart cells via a vitamin D receptors found in cardiomyocytes. We present the case of a patient with vitamin D deficiency and symptomatic premature ventricular contractions (PVCs), in whom cardiac rehabilitation decreased PVC number, but association with vitamin D supplements led to a significant decrease in PVCs and complete disappearance of symptoms. Keywords: cardiac rehabilitation, vitamin D, ventricular premature contractions, physical activity,

Endocardial vs endo-epicardial ablation of ventricular arrhythmia in arrhythmogenic right ventricular cardiomyopathy: a single center experience

Abstract Background The majority of patients have a sub-epicardial scar as a substrate for VT episodes. Purpose We sought to compare the efficacy of endocardial (ENDO) and epicardial (EPI) substrate modification in patients with ARVC. Methods 20 consecutive ARVC patients (mean age 41,4±13,8, 70% males; ICD previously implanted in 10 patients) with indications to ventricular arrhythmia ablation (RFA) were included into a prospective observational study. The EPI group consisted of 10 patients with sustained ventricular tachycardia (VT) (definite diagnosis ARVC – 8 patients; borderline – 1, possible – 1) who signed an informed consent to epicardial access. The ENDO group included 10 patients (definite diagnosis ARVC – 9 patients), five of them demonstrated sustained VT and 5 patients had frequent symptomatic premature ventricular contractions (PVC). Epicardial access in the EPI group was obtained through subxyphoid puncture. Bi- and unipolar voltage mapping of endocardial and epicardial surfaces was performed. Maps were evaluated for the presence of local abnormal ventricular electrical activity (LAVA, low-voltage areas and sites with highly fractionated or late activity). Ablation was performed at sites of LAVA on either side of the ventricular wall. In the ENDO group endocardial only ablation at LAVA sites was performed. RF energy ablation was 40W at the epicardial surface and 40–50W at the endocardial surface. Results In the EPI group endocardially mapped area of unipolar endocardial low voltage zone (LVZ) significantly prevailed over bipolar endocardial area of LVZ: 75.4 cm2 [IQR: 23.2; 211.9] vs 6.7 cm2 [IQR: 4.4; 35.5](P=0.009). Epicardial bipolar LVZ area prevailed over unipolar epicardial LVZ area: 65.3 cm2 [IQR: 55.6; 91.3] vs 6.7 cm2 [IQR: 4.4; 35.3] (P=0.005). Endocardial unipolar LVZ area in the EPI group was larger than in the ENDO group (P&amp;gt;0,05). After ablation non-inducibility of any ventricular arrhythmia was achieved in 90% of patients in the EPI group and in 80% of cases in the ENDO group. During a mean follow-up period of 22.3±10.5 months freedom of ventricular arrhythmia recurrence was 70% in the EPI group and 100% in the control group. Conclusions Although epicardial area of abnormal potentials significantly prevails over endocardial area, endocardial unipolar mapping and higher RF ablation power allow performing successful ventricular arrhythmia treatment in the majority of ARVC patients. Funding Acknowledgement Type of funding source: None

Successful ablation of premature ventricular contractions exclusively guided by epicardial and endocardial non-invasive mapping (ECGI) and confirmed by substrate mapping

Ablation of premature ventricular contractions (PVCs), relies mostly on a detailed activation mapping. This can be impossible to achieve in case of paucity or even absence of PVCs during the procedure. Pacemapping as an alternative has many limitations. We present a case of a patient with very frequent symptomatic PVCs, that on the day of the procedure had total absence of PVCs. We performed successful ablation based exclusively on electrocardiographic imaging confirmed by substrate mapping.

Endocardial and endo-epicardial substrate mapping and ablation of ventricular arrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy

Purpose: to compare epicardial and endocardial surface area of local abnormal ventricular activity (LAVA) and low voltage zone (LVZ) and effectiveness of endocardial versus combined endo-epicardial ablation of ventricular arrhythmias in ARVC patients.Methods: a prospective observational “case-control” study comprised 20 patients with ARVC and ventricular arrhythmias referred to catheter ablation. The study group with epicardial approach (EPI group) comprised 10 patients with sustained VT, who signed informed consent for the epicardial access. The control group (ENDO group) comprised 10 patients with sustained VT or frequent symptomatic premature ventricular contractions (PVC). Electroanatomical voltage mapping and LAVA ablation was performed.Results: the patient mean age was 41.4±13.8 years, 70% males; 90% patients in the EPI group had sustained VT, 50% - in the ENDO group. In the EPI group the endocardial unipolar low voltage zone area (LVZ) significantly prevailed over the bipolar endocardial LVZ area: 75.4 cm2 [IQR: 23.2; 211.9] vs 6.7 cm2 [IQR: 4.4; 35.5] (Р=0.009). In the ENDO group the LVZ area on unipolar map had a trend toward the prevalence over the bipolar area, but was not statistically different: 12.7 cm2 (IQR: 0; 46.3) vs 3.65 cm2 (IQR: 0; 46.3) (Р&gt;0.05). The epicardial bipolar LVZ area prevailed over unipolar epicardial LVZ area: 65.3 cm2 [IQR: 55.6; 91.3] vs 6.7 cm2 [IQR: 4.4; 35.3] (Р=0.005). Non-inducibility of any ventricular arrhythmia was achieved in 90% of EPI patients and in 80% of ENDO cases. The median follow-up period was 22.3±10.5 months. During a mean follow-up period freedom of ventricular arrhythmia recurrence was 70% in the EPI group and 100% in the control group (Р&gt;0.05).Conclusion: Although there was a significant difference in bipolar LVZ areas between endo- and epicardial maps, our series showed that endocardial only ablation is an effective strategy in ventricular arrhythmia management in ARVC patients.

Benefit of Contact Force-Guided Catheter Ablation for Treating Premature Ventricular Contractions.

We evaluated whether an irrigated contact force-sensing catheter would improve the safety and effectiveness of radiofrequency ablation of premature ventricular contractions originating from the right ventricular outflow tract. We retrospectively reviewed the charts of patients with symptomatic premature ventricular contractions who underwent ablation with a contact force-sensing catheter (56 patients, SmartTouch) or conventional catheter (59 patients, ThermoCool) at our hospital from August 2013 through December 2015. During a mean follow-up of 16 ± 5 months, 3 patients in the conventional group had recurrences, compared with none in the contact force group. Complications occurred only in the conventional group (one steam pop; 2 ablations suspended because of significantly increasing impedance). In the contact force group, the median contact force during ablation was 10 g (interquartile range, 7-14 g). Times for overall procedure (36.9 ± 5 min), fluoroscopy (86.3 ± 22.7 s), and ablation (60.3 ± 21.4 s) were significantly shorter in the contact force group than in the conventional group (46.2 ± 6.2 min, 107.7 ± 30 s, and 88.7 ± 32.3 s, respectively; P <0.001). In the contact force group, cases with a force-time integral <560 gram-seconds (g-s) had significantly longer procedure and fluoroscopy times (both P <0.001) than did those with a force-time integral ≥560 g-s. These findings suggest that ablation of premature ventricular contractions originating from the right ventricular outflow tract with an irrigated contact force-sensing catheter instead of a conventional catheter shortens overall procedure, fluoroscopy, and ablation times without increasing risk of recurrence or complications.

232 Mediastinal Injury following Radiofrequency Catheter Ablation for Symptomatic Premature Ventricular Contractions - a Case Report

232 Mediastinal Injury following Radiofrequency Catheter Ablation for Symptomatic Premature Ventricular Contractions - a Case Report

Myocarditis Causing Premature Ventricular Contractions

Premature ventricular contractions are a common clinical presentation that drives further diagnostic workup. We hypothesize the presence of underlying inflammation is often unrecognized in these patients with a potential for continued disease progression if not diagnosed and treated early in the disease course. This is a single-center, prospective study including 107 patients with frequent symptomatic premature ventricular contractions (>5000/24 h) and no known ischemic heart disease. Patients underwent a combination of laboratory testing, 18F-fluorodeoxyglucose positron emission tomography scan, cardiac magnetic resonance imaging, and biopsy. Patients were diagnosed with myocarditis based on a multidisciplinary approach and treated with immunosuppressive therapy. The mean age of the cohort was 57±15 years, 41% were males, and left ventricular ejection fraction was 47±11.8%. Positive positron emission tomography scan was seen in 51% (55/107), of which 51% (28/55) had preserved left ventricle function. Based on clinical profile, 18F-fluorodeoxyglucose-positron emission tomography imaging, cardiac magnetic resonance, and histological data 58% patients (32/55) received immunosuppressive therapy alone and 25.4% (14/55) received immunosuppressive therapy and catheter ablation. Optimal response was seen in 67% (31/46) over a mean follow-up of 6±3 months. In patients with left ventricle systolic dysfunction, 37% (10/27) showed an improvement in mean left ventricular ejection fraction of 13±6%. Approximately 51% of patients presenting with frequent premature ventricular contractions have underlying myocardial inflammation in this cohort. 18F-fluorodeoxyglucose-positron emission tomography scan can be a useful modality for early diagnosis and treatment with immunosuppressive therapy in selected patients can improve clinical outcomes.

P919Ventricular arrhythmias in patients with mitral valve prolapse and severe mitral regurgitation

Abstract Background Mitral valve prolapse (MVP) is known to be associated with ventricular arrhythmias (VA), from symptomatic premature ventricular contractions (PVCs) to malignant ventricular tachycardia (VT) and sudden cardiac death (SCD). Previous studies identified risk factors for VA in these patients such as young woman, bileaflet prolapse and inverted T-waves, but they included only specific cohort of patients who experienced SCD or who had only trivial or mild mitral regurgitation (MR). The prevalence of VA and their potential risk factors in a population of MVP patients with severe MR are unknown. Purpose The aim of our study was to describe the prevalence of VA in patients who underwent mitral valve surgery for moderate to severe MR due to MVP and to identify clinical, electrocardiographic and echocardiographic parameters associated with VA. Methods 797 patients (65±12 years, 65% male) who underwent surgery for MVP were included from 2000 until 2018. The presence of VA was defined as symptomatic and frequent PVCs (Lown grade ≥2), non-sustained ventricular tachycardia (nsVT), VT or ventricular fibrillation (VF) documented before surgery and without an ischemic cause. The echocardiogram and electrocardiogram (ECG) prior to operation were used for the specific analysis. ECGs were checked for rhythm, conduction times, QRS morphology and inferior T-wave inversion. The origin of the PVCs was derived from a 12-lead ECG when available and divided in 5 groups; mitral annulus, papillary muscle (PM), left ventricle (LV, including outflow tract), right ventricle (including outflow tract) and other. By echocardiography, several parameters such as LV thickness and volumes, LV ejection fraction (EF), global longitudinal strain (GLS) and MR grade were obtained. Results A total of 99 (12%) patients showed VA; 70% (69/99) of the patients had symptomatic PVCs, 36% (36/99) had nsVT, 12% (12/99) VT and 3% (3/99) VF. 21 patients had more than one type of VA, of which the combination PVCs and nsVT was the most common (19/99, 19%). In addition, 6 patients experienced an out of hospital cardiac arrest of a non-ischemic cause. When comparing the clinical characteristics (Table), patients with VA were significantly younger (and with better renal function), more frequently diagnosed with Barlow's disease and experienced more palpitations as compared to patients without VA. The ECG analysis showed that patients with VA more often had inferior T-wave inversions and that the PVCs predominantly originated from the PM whereas in patients without VA the PVCs originated from different regions. Echocardiography showed that patients with VA had a thinner posterior wall, reduced LV EF and worse GLS; more severe MR was not associated with VA. Conclusion In MVP patients with moderate to severe MR undergoing surgery, Barlow's disease, inferior T-wave inversions, thinner posterior wall and LV systolic dysfunction are associated with the presence and development of VA.

P3833Low heart rate variability is associated with future arrhythmic events in hypertension

Abstract Background/Introduction Cardiac autonomic dysfunction and target organ damage are associated with increased cardiovascular mortality and arrhythmias. Purpose The aim of the study was to investigate the effect of heart rate variability (HRV) and markers of target organ damage in the prognosis of future arrhythmic events. Methods We studied 292 untreated at baseline hypertensives (mean age 53±13, 153 males). Cardiac autonomic function was evaluated by analysis of short-term HRV measures over 24-h using 24-h ambulatory blood pressure monitoring and the standard deviation of the measurements. Echocardiography was also performed and left ventricular mass index (LVMI) was estimated with the Demereux formula. Aortic stiffness was assessed with carotid-femoral pulse wave velocity (cfPWV) and wave reflections with aortic augmentation index corrected for heart rate (Alx@75). Patients were followed up for a median period of 13 years. The primary endpoint was a composite of atrial/ventricular tachycardias, symptomatic multiple premature ventricular contractions, second and third-degree heart blocks and pacemaker/defibrillator placement. Results In comparison without events, patients with the primary endpoint (n=37, 13%) had lower 24-h daytime HRV (9.6 beats per minute vs. 11.1 beats per minute, p=0.005), higher systolic blood pressure (168 mmHg vs. 163 mmHg, p=0.003), higher cfPWV (8.4 m/s vs. 7.7 m/s, p=0.005), higher LVMI (133 g/m2 vs. 122 g/m2, p=0.002) and higher AIx@75 (29.0% vs. 26.3%, p=0.043). In further analysis, receiver operating characteristic (ROC) curves were generated to evaluate the ability of HRV, cfPWV, LVMI and AIx@75 to discriminate subjects with arrhythmic events. The area under the curve (AUC) and 95% CIs of the ROC curves were AUC=0.35 (95% CI: 0.26–0.44, p=0.003) for HRV, AUC=0.64 (95% CI: 0.54–0.73, P&lt;0.006) for cfPWV, AUC=0.67 (95% CI: 0.58–0.75, P=0.001) for LVMI and AUC=0.55 (95% CI: 0.47–0.64, P=0.298) for AIx@75 (Figure). In Cox regression analysis, only HRV was associated with increased risk of arrhythmic events (Hazard ratio per 1 unit =0.87, 95% Confidence intervals 0.76 to 0.995, p=0.043) when adjusted for age, gender, cfPWV, LVMI and AIx@75. ROC curves of HRV &amp; target organ damage Conclusions Low heart rate variability is associated with increased risk of future arrhythmic events suggesting an early sympathovagal imbalance that could lead to future events in hypertension.