Frequent Premature Ventricular Contractions Research Articles

Acute Efficacy of a Traditional Chinese Medicine for Treatment of Frequent Premature Ventricular Contractions in Patients with Concomitant Sinus Bradycardia: Results from a Double-Blind, Placebo-Controlled, Multicentre, Randomized Clinical Trial.

Pharmacological antiarrhythmic therapy such as beta-blockers in patients with frequent premature ventricular contractions (PVCs) and concomitant bradycardia is challenging. A traditional Chinese medicine, Shensong Yangxin (SSYX), has been effective in treatment of frequent PVCs and sinus bradycardia (SB) in separate patient cohorts. This double-blind, placebo-controlled, multicentre, randomized clinical trial investigates the acute efficacy of SSYX in reducing PVCs burden in patients with concomitant SB. Patients with symptomatic, frequent PVCs, and SB, defined as mean heart rate (MHR) of 45 to 59 beats per min (bpm), were recruited at 33 medical centres in mainland China and randomly assigned by computer to either SSYX or matching placebo for eight weeks. Patients, investigators, and trial personnel were masked to treatment allocation. Primary endpoints were changes in PVCs burden and MHR as assessed by 24-hour Holter monitoring relative to baseline. Secondary efficacy endpoints were subjective symptom score, ECG, and biochemical parameters. Analysis was based on intention-to-treat principles. 333 patients were randomized, of which 166 received SSYX and 167 placebo. Baseline characteristics did not differ. SSYX reduced PVCs burden by 68.2% (p < 0.001) and increased MHR by 10.9% (p < 0.001) compared to 32.2% and 4.7%, respectively, in the placebo group. SSYX group experienced greater symptomatic improvement (p < 0.001). No differences in reported adverse events were seen (20 versus 23). SSYX is an effective antiarrhythmic therapy for symptomatic, frequent PVCs uniquely suited patients with concomitant SB. Clinical trial number was NCT01750775.

Radiofrequency catheter ablation of premature ventricular contractions from near the His-bundle.

ObjectiveThis study aimed to investigate the effects of radiofrequency catheter ablation (RFCA) and clinical and electrophysiological characteristics in symptomatic patients with premature ventricular contractions (PVCs) from near the His‐bundle (His‐PVCs).MethodsThe patient characteristics, prevalence of complications with any life style related disease (ALSRD) including hypertension, dyslipidemia, or diabetes mellitus, and/or cardiovascular disease (CVD) including coronary artery disease, cerebrovascular disease, renal dysfunction, or cardiomyopathy, clinical status, frequency of PVCs evaluated by 24hour Holter monitoring, echocardiography including the left ventricular diastolic dysfunction (LVDD) parameters, and electrophysiological findings were evaluated in 14 consecutive symptomatic patients with His‐PVCs.ResultsThe prevalence of males, being elderly and/or slightly obese, current and/or history of smoking, ALSRD or CVD related complications, and LVDD probably resulting from ALSRD and/or CVD complications were higher in patients with His‐PVCs. RFCA of His‐PVCs steadily decreased the PVC frequency and improved the systolic function, LV dilation, and clinical status, but not the LVDD. There was a significant relationship between the accordance rate of the QRS polarity between sinus rhythm and His‐PVCs and the distance between the successful ablation site and His‐bundle.ConclusionThe analysis of the QRS duration and accordance rate of the QRS polarity between sinus rhythm and His‐PVCs before the RFCA may help to determine the distance between the origin of the PVCs and His‐bundle. Further, the appropriate ablation catheter may be selected during the RFCA procedure. Finally, RFCA may be one of the most effective, feasible, and safest therapies for symptomatic patients with His‐PVCs.

Isolated diastolic potentials as predictors of success in ablation of right ventricular outflow tract idiopathic premature ventricular contractions.

Background and aimsDiscrete potentials, low voltage and fragmented electrograms, have been previously reported at ablation site, in patients with premature ventricular contractions (PVCs) originating in the right ventricular outflow tract (RVOT). The aim of this study was to review the electrograms at ablation site and assess the presence of diastolic potentials and their association with success.MethodsWe retrospectively reviewed the electrograms obtained at the radiofrequency (RF) delivery sites of 48 patients subjected to ablation of RVOT frequent PVCs. We assessed the duration and amplitude of local electrogram, local activation time, and presence of diastolic potentials and fragmented electrograms.ResultsWe reviewed 134 electrograms, median 2 (1–4) per patient. Success was achieved in 40 patients (83%). At successful sites the local activation time was earlier– 54 (-35 to -77) ms vs -26 (-12 to -35) ms, p<0.0001; the local electrogram had lower amplitude 1 (0.45–1.15) vs 1.5 (0.5–2.1) mV, p = 0.006, and longer duration 106 (80–154) vs 74 (60–90) ms, p<0.0001. Diastolic potentials and fragmented electrograms were more frequently present, respectively 76% vs 9%, p <0.0001 and 54% vs 11%, p<0.0001. In univariable analysis these variables were all associated with success. In multivariable analysis only the presence of diastolic potentials [OR 15.5 (95% CI: 3.92–61.2; p<0.0001)], and the value of local activation time [OR 1.11 (95% CI: 1.049–1.172 p<0.0001)], were significantly associated with success.ConclusionIn this group of patients the presence of diastolic potentials at the ablation site was associated with success.

Premature ventricular contractions of the right ventricular outflow tract: Upward displacement of the ECG unmasks ST elevation in V1 associated with the presence of low voltage areas

Introduction and AimsFrequent premature ventricular contractions (PVCs) originating from the right ventricular outflow tract (RVOT) are usually considered a benign entity and the ECG is typically normal. The aim of this study was to assess whether upward displacement of the ECG to the second intercostal space (ICS) would reveal any abnormal pattern. MethodsA total of 18 consecutive patients with apparently normal hearts were studied, mean age 44±16 years, 12 women, who underwent catheter ablation of the RVOT due to frequent PVCs. A 12-lead ECG was performed in the standard position and repeated in a higher position, at the level of the second ICS. Three-dimensional bipolar electroanatomical voltage mapping (EVM) was performed in all patients and low voltage areas (LVAs) were defined as areas with amplitude <1.5 mV. ResultsThe ECG in the second ICS was normal in eleven patients but in seven (39%) it revealed a pattern of ST-segment elevation in V1. EVM revealed the presence of LVAs in six patients (33%) which included the earliest activation site (EAS) in five. The ST elevation was associated with the presence of LVAs (p<0.0001) and with the LVAs at the EAS (p=0.002). ConclusionIn this group of patients with apparently normal hearts and with frequent PVCs of the RVOT, upward displacement of the ECG revealed the presence of ST elevation in more than one third of patients, and the ST elevation was associated with the presence of LVAs in the RVOT.

Clinical Overview of Obesity and Diabetes Mellitus as Risk Factors for Atrial Fibrillation and Sudden Cardiac Death.

The epidemics of obesity and diabetes mellitus are associated with an increased incidence of both atrial fibrillation (AF), the most common sustained arrhythmia in adults, and sudden cardiac death (SCD). Obesity and DM are known to have adverse effects on cardiac structure and function. The pathologic mechanisms are thought to involve cardiac tissue remodeling, metabolic dysregulation, inflammation, and oxidative stress. Clinical data suggest that left atrial size, epicardial fat pad thickness, and other modifiable risk factors such as hypertension, glycemic control, and obstructive sleep apnea may mediate the association with AF. Data from human atrial tissue biopsies demonstrate alterations in atrial lipid content and evidence of mitochondrial dysfunction. With respect to ventricular arrhythmias, abnormalities such as long QT syndrome, frequent premature ventricular contractions, and left ventricular hypertrophy with diastolic dysfunction are commonly observed in obese and diabetic humans. The increased risk of SCD in this population may also be related to excessive cardiac lipid deposition and insulin resistance. While nutritional interventions have had limited success, perhaps due to poor long-term compliance, weight loss and improved cardiorespiratory fitness may reduce the frequency and severity of AF.

Excessive Atrial Ectopic Activity Worsens Prognosis and Predicts the Type of Major Adverse Cardiac Events in Patients With Frequent Premature Ventricular Contractions.

BackgroundThe aim of the study was to evaluate the impact of premature atrial contractions (PACs) burden, and the presence of non-sustained ventricular tachycardia (NSVT) on prognosis and type of major adverse cardiovascular events in patients with frequent premature ventricular contractions (PVCs).MethodsWe retrospectively studied 285 consecutive patients with frequent PVCs defined as PVC count equal or higher than 1% of total beats assessed with 24-h Holter recording. Patients with atrial fibrillation (AF) were excluded. We evaluated the impact of PAC burden and the presence of NSVT on the primary end points of all-cause mortality, stroke and new-onset AF, and secondary end points; arrhythmic end point (arrhythmic death or hospitalizations for ventricular arrhythmias) or heart failure (HF)-related end point (death or hospitalizations due to HF).ResultsThe PAC number showed an adjusted hazard ratio (HR) (95% confidence interval (CI), P value) of 1.077 (1.014 - 1.145, P = 0.017) for all-cause mortality, 1.250 (1.080 - 1.447, P = 0.003) for stroke, 1.090 (1.006 - 1.181, P = 0.036) for new-onset AF and 1.376 (1.128 - 1.679, P = 0.002) for the HF end point. The presence of NSVT showed an adjusted HR (95% CI) of 3.644 (1.147 - 11.57, P = 0.028) for the arrhythmic end point.ConclusionsIn patients with frequent PVCs a high PAC count was independently associated with increased mortality, higher rate of AF, stroke and HF adverse events, but not with arrhythmic adverse events. The presence of NSVT was independently associated with increased arrhythmic adverse events, but not with overall mortality, AF, stroke or HF events.

Hemodynamic consequences of premature ventricular contractions: Association of mechanical bradycardia and postextrasystolic potentiation with premature ventricular contraction-induced cardiomyopathy

The relationships between hemodynamic consequences of premature ventricular contractions (PVCs) and development of premature ventricular contraction-induced cardiomyopathy (PVC-CM) have not been investigated. The purpose of this study was to correlate concealed mechanical bradycardia and/or postextrasystolic potentiation (PEP) to PVC-CM. Invasive arterial pressure measurements from 17 patients with PVC-CM and 16 controls with frequent PVCs were retrospectively analyzed. PVCs were considered efficient (ejecting PVCs) when generating a measurable systolic arterial pressure. PEP was defined by a systolic arterial pressure of the post-PVC beat ≥5 mm Hg higher than the preceding sinus beat. Every PVC was analyzed for 10 minutes before ablation, and the electromechanical index (EMi = number of ejecting PVCs/total PVC) and postextrasystolic potentiation index (PEPi = number of PVCs with PEP/total PVC) were calculated. EMi was 29% ± 31% in PVC-CM and 78% ± 20% in controls (P <.0001). PEPi was 41% ± 28% in PVC-CM and 14% ± 10% in controls (P = .001). There was no control in groups of low EMi or high PEPi. EMi and PEPi were not significantly correlated to left ventricular dimensions or function in PVC-CM patients. PVC coupling interval was related to both ejecting PVCs and PEP. Patients with PVC-CM more often display nonejecting PVCs and PEP compared to controls.

Role of Cardiac Magnetic Resonance Imaging in Patients with Idiopathic Ventricular Arrhythmias.

Ventricular Arrhythmias (VAs) may present with a wide spectrum of clinical manifesta-tions ranging from mildly symptomatic frequent premature ventricular contractions to life-threatening events such as sustained ventricular tachycardia, ventricular fibrillation and sudden cardiac death. Myocardial scar plays a central role in the genesis and maintenance of re-entrant arrhythmias which are commonly associated with Structural Heart Diseases (SHD) such as ischemic heart disease, healed myocarditis and non-ischemic cardiomyopathies. However, the arrhythmogenic substrate may remain unclear in up to 50% of the cases after a routine diagnostic workup, comprehensive of 12-lead surface ECG, transthoracic echocardiography and coronary angiography/computed tomography. Whenever any abnormality cannot be identified, VAs are referred as to “idiopathic”. In the last dec-ade, Cardiac Magnetic Resonance (CMR) imaging has acquired a growing role in the identification and characterization of myocardial arrhythmogenic substrate, not only being able to accurately and re-producibly quantify biventricular function, but, more importantly, providing information about the presence of myocardial structural abnormalities such as myocardial fatty replacement, myocardial oe-dema, and necrosis/ fibrosis, which may otherwise remain unrecognized. Moreover, CMR has recent-ly demonstrated to be of great value in guiding interventional treatments, such as radiofrequency abla-tion, by reliably identifying VA sites of origin and improving long-term outcomes. In the present manuscript, we review the available data regarding the utility of CMR in the workup of apparently “idiopathic” VAs with a special focus on its prognostic relevance and its application in planning and guiding interventional treatments.

The Relationship Between Premature Ventricular Contractions and Lifestyle-Related Habits among the Japanese Working Population (FUJITSU Cardiovascular and Respiratory Observational Study-1; FACT-1).

Premature ventricular contractions (PVCs) are often found in healthy workers at medical checkups. In this study, we aimed to investigate the frequency of PVCs recorded during medical checkups in Japanese office workers without heart disease or other known contributing factors. Participants in this study were 17,641 office workers, who underwent an electrocardiogram examination during a regular medical checkup between April 1 2015 and March 31 2016 and had no known heart disease. The frequency of PVCs was recorded. Participants with PVCs were included in the PVC group and a control group of participants without PVCs was set in a nested case-control study to calculate the rate of complications for lifestyle-related diseases and the risk rate of PVCs for lifestyle-related habits. Within the participant group, PVCs were observed in 303 individuals (1.7%). When compared with the control group, the occurrence of regularly drinking alcohol (P=0.009) and insomnia (P=0.006) were significantly higher in the PVC group. Factors related to the onset of PVCs were examined using univariate analysis. The odds ratio (OR) was 1.731 in participants who regularly drank alcohol (95% CI: 1.146-2.633, P=0.009) when compared with participants who did not regularly drink alcohol, and 1.569 in participants with insomnia (95% CI: 1.023-2.422, P=0.040) when compared with participants without insomnia. The frequency of PVCs recorded at regular medical checkups in Japanese office workers without heart disease was 1.7%. Within our group of participants, the factors related to the onset of PVCs were a history of regularly drinking alcohol and sleep disorders.

Abstract 17270: Prognostic Impact of Ventricular Ectopy During the Recovery Phase of Stress Testing: A Meta-Analysis

Introduction: Ventricular ectopy after exercise, due to parasympathetic activity, predicts an increased risk of death in population-based cohorts. We sought to examine the composite risk of all cause mortality in patients with premature ventricular contractions (PVCs) in the early recovery phase of stress testing. Methods: PubMed, Medline &amp; EMBASE were queried for all English language articles from 1993 to 2017. The primary outcome was incidence of all cause mortality in patients with frequent PVCs during recovery phase (RPV) of stress testing. Frequent PVCs were defined as the presence of seven or more ventricular premature beats/min, frequent ventricular couplets, ventricular bigeminy or trigeminy, or any other form of ventricular tachycardia or ventricular fibrillation. Meta-analysis of the main outcome was performed using a weighted random effects model. Results: A total of four observational studies including 38765 patients were retrieved. Data for 2065 patients with RPV was pooled. A comparative analysis of PVC vs Infrequent/Non-PVC group showed a calculated risk ratio for all cause mortality of 1.8 (95% CI 1.36-2.38; p=0.001). I 2 statistic for heterogeneity testing was 82.8% (Fig.1). Conclusion: Frequent premature ventricular contractions during early recovery phase of stress testing are associated with increased all cause mortality as compared to patients with infrequent or no PVCs.

The safety of catheter ablation for premature ventricular contractions in patients without structural heart disease

BackgroundPatients with frequent premature ventricular contractions (PVCs) are often symptomatic. Catheter ablation was usually indicated to eliminate symptoms in patients with PVCs-induced cardiomyopathy. Currently, PVCs-ablation is also applied for patients with PVCs and no structural heart diseases (SHD); however, the safety and efficacy of ablation in these patients remains unclear.MethodsIn this retrospective study, data from patients who underwent ablation for PVCs from January 2010 to December 2016 at our hospital was retrieved. Predictors of complications and acute procedural success were evaluated.ResultsA total of 1231 patients (mean age 47.8 ± 16.8 years, 59% female) were included. The overall complication rate was 2.7%, and the most common complication was hydropericardium. Two ablation-related mortalities occurred. One patient died of coronary artery injury during the procedure and the other died from infectious endocarditis. Location (left ventricle and epicardium) was the main predictor of complications, with right ventricular outflow tract (RVOT) predicting fewer complications. The acute procedural success rate was 94.1% in all patients. The main predictor of acute procedural success was RVOT origin, while an epicardial origin was a predictor of procedural failure.ConclusionLocations of left ventricle and epicardium were predictors of procedural complications for patients with PVCs. Therefore, ablation is not recommended in these patients. For other origins of PVCs, particularly RVOT origin, ablation is a safety and effective treatment.

A novel familial truncating mutation in the filamin C gene associated with cardiac arrhythmias

The authors report for the first time a novel mutation in the FLNC gene associated with cardiac arrhythmias in two half-siblings. The FLNC gene on chromosome 7q32 encodes filamin C, which stabilizes the actin network within the cardiomyocyte. The proband is an 8-year-old asymptomatic patient with frequent premature ventricular contractions noted on serial monitoring. Interestingly, the proband and his half-brother harbored a heterozygous 13 base pair deletion that resulted in a frameshift mutation and introduction of a premature stop codon. Notably, the proband also had a very tragic family history of sudden death in young individuals involving three generations and five family members. Because of their concerning family history and arrhythmias, both siblings underwent off-label implantable cardiac device placement for primary prevention of sudden cardiac death. Whether or not the FLNC mutation is associated with sudden cardiac death requires additional investigation and is beyond the scope of this manuscript. While previous studies have identified several mutations in the FLNC gene associated with dilated and hypertrophic cardiomyopathies, the goal of this study was to report a novel mutation in the FLNC gene that is associated with cardiac arrhythmias. The current study indicates that this mutation may help identify patients at risk for cardiac arrhythmias who would benefit from further cardiac evaluation.

Isolated Right Ventricular Cardiac Sarcoidosis Presenting as Complete Heart Block

Introduction Sarcoidosis is a multi-organ disease with formation of granulomas. Involvement of the heart causes inflammation, leading to atrioventricular block (AVB) or ventricular arrhythmias, and portends a poor prognosis. Cardiac sarcoidosis is detected in only 2% of patients, and most have left ventricular (LV) involvement. Isolated right ventricular (RV) involvement is rare. High suspicion is necessary to make the diagnosis, and advanced testing is required. Recognizing cardiac sarcoid is imited to the RV and determining presence of pulmonary hypertension (PH), is imperative for management. Case Presentation A 53 yo woman presented with dyspnea and palpitations. She has a history of complete heart block (CHB) requiring permanent pacemaker placement, and atrial arrhythmias. On evaluation, BP 153/81 mmHg and HR 71 bpm. Physical exam was normal. Given clinical history and refractory dyspnea, there was concern for an inflammatory process. Cardiac monitoring revealed frequent premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia (NSVT). An echocardiogram demonstrated normal valvular and LV function, but the RV was severely dilated with moderate dysfunction. A right -heart catheterization (RHC) demonstrated normal pulmonary artery pressures and pulmonary capillary wedge pressure. A nuclear PET scan showed areas of increased FDG uptake within the RV, distal anteroseptal LV and pericardium, concerning for sarcoidosis. An endomyocardial biopsy (EMB) demonstrated multinucleated giant cells, confirming sarcoidosis. The patient underwent radiofrequency ablation for AFL. Her device was upgraded to a defibrillator. She was initiated on Cellcept. Serial echocardiograms revealed no PH and stable RV size and function. Case Discussion The diagnosis of cardiac sarcoidosis is elusive due to non-specific signs and symptoms. It often presents with CHB, ventricular arrhythmias or sudden death, atrial arrhythmias, or heart failure. Our patient was diagnosed with CHB, then went on to develop atrial and ventricular arrhythmias, and RV failure. The majority of patients with cardiac involvement have LV involvement. There are only a few case reports of isolated RV involvement. Since lone RV cardiac sarcoidosis is uncommon, diagnosis is delayed. Fortunately in our patient, once sarcoidosis was confirmed to be primarily involving the RV, a RHC and serial transthoracic echocardiograms were performed to rule out PH, which would influence treatment. Conclusion Cardiac sarcoidosis is rare, identified in only 25% of patients with systemic sarcoidosis, and has a poor prognosis. A high degree of suspicion is warranted, especially among young patients with arrhythmias of unclear etiology. Further investigation with serologic ACE levels, imaging such as cardiac magnetic resonance imaging (CMR) or nuclear PET scan, and EMB should be done. Finally, periodic echocardiograms and RHCs are necessary to ensure PH does not develop, which has implications for management.

Electrophysiological Characteristics of Bundle Branch Reentry Ventricular Tachycardia in Patients Without Structural Heart Disease

The distinct electrophysiological features of bundle branch reentry ventricular tachycardia (VT) in patients without structural heart disease have not been systemically characterized. Nine patients (mean age, 29.6 years) with normal left ventricular function were enrolled. Bundle branch reentry VT with right and left bundle branch block (BBB) patterns was induced in 1 and 9 patients, respectively. The right bundle was attempted to record by a 6F decapolar or quadripolar catheter. Electroanatomic mapping of the left ventricle was performed in 6 patients. In all left BBB pattern VT, the mean VT cycle length was 329.3±89.1 ms, and the median HV interval during tachycardia was longer than that of baseline (78 [73-100] versus 71 [64.5-88] ms; P=0.11). The H-RB interval during VT was slightly shorter (P=0.14); however, the median RB-V interval was markedly longer than that during sinus rhythm (50 [29.5-83] versus 30 [8-51] ms; P=0.043]. In 6 patients with 3-dimensional mapping of the left ventricle, a slow anterograde or retrograde conduction over left HIS-Purkinje system with normal myocardial voltage was identified. In addition, Purkinje-related VTs (1.0±1.3 types) were also induced in 5 patients. Ablation was applied in distal left BB in patients with baseline left BBB and in one narrow QRS patient with sustained Purkinje-related VT, whereas right BB was targeted in other patients. During a mean follow-up of 31.4 months, frequent premature ventricular contractions occurred in one patient, and new VT developed in the other patient. Bundle branch reentry VT can occur in young patients with extensive conduction disturbances within HIS-Purkinje system. Ablation targeting at the distal left BB which bifurcates into left posterior and anterior fascicle can preserve the residual atrioventricular conduction, but intensive follow-up is needed.

Astragalus mongholicus (Fisch.) Bge Improves Peripheral Treg Cell Immunity Imbalance in the Children With Viral Myocarditis by Reducing the Levels of miR-146b and miR-155.

Viral myocarditis (VMC) is a common cardiac disease, however, there still lacks an effective therapeutic strategy for VMC. Astragalus mongholicus (Fisch.) Bge (AB), a Chinese herb with some functional metabolites, may have some pharmacological effects on VMC. AB ingredients were measured by a full-scan LCQ mass spectrum. We aimed to explore the effects of AB on the VMC children by investigating peripheral Treg cell homeostasis. A total of 68 VMC children were random and evenly assigned into an AG group (received 10-mL AB oral liquid daily), and a CG group (received placebo daily). Peripheral blood mononuclear cells (PBMC) were obtained from peripheral blood and Treg cells were isolated. The levels of miR-146b, miR-155, Treg immunity activity and myocarditis biomarkers were measured in Treg cells. There were four main components (sucrose, calycosin, Astragaloside IV and calycosin-7-glucoside) in AB. The cases sinus tachycardia, frequent premature ventricular contractions, and supraventricular tachycardia were significantly reduced in the AG group (P < 0.05). Meanwhile, the myocardial enzymes and cardiac function indexes were improved in the AG group when compared with the CG group (P < 0.05). The time of electrocardiogram recovery, symptom duration and hospital stay was shorter in the AG group than in the CG group (P < 0.05). The levels of miR-146b and miR-155 were higher in the CG group than in the AG group (P < 0.05). The levels of ROR-γt (retinoic acid receptor-related orphan nuclear receptor gamma), FoxP3 (forkhead transcription factor), IL-10 (interleukin-11) and TGF-β (transforming growth factor beta) were lower in the CG group than in the AG group (P < 0.05). In contrast, the levels of IL-17, IL-21, CK-MB (creatine kinase-MB), cTnI (cardiac troponin I), GrB (granzyme B), sFasL (soluble fas ligand) and caspase-3 were higher in the CG group than in the AG group (P < 0.05). Furthermore, the levels of ROR-γt, FoxP3, IL-10, and TGF-β were positively, whereas the levels of IL-17, IL-21, CK-MB, cTnI, GrB, sFasL and caspase-3 were negatively, associated with the levels of miR-146b and miR-155 (P < 0.05). AB treatment improved cardiac functions, peripheral Treg cell immunity imbalance in the children with VMC by reducing the levels of miR-146b and miR-155.

Reversibility of Frequent Premature Ventricular Contraction Induced Cardiomyopathy after Radiofrequency Catheter Ablation

Reversibility of Frequent Premature Ventricular Contraction Induced Cardiomyopathy after Radiofrequency Catheter Ablation

Abstract P022: The Association of Sleep Apnea With Atrial Fibrillation and Ectopy Using Ambulatory Electrocardiogram in the Atherosclerosis Risk in Communities (ARIC) Study

Introduction: Sleep apnea (SA) is associated with burden of atrial fibrillation (AF), but studies of SA and ectopic beats, potential triggers of AF, are sparse. Our study contributes by examining the association of SA with AF, premature atrial contractions (PACs), and premature ventricular contractions (PVCs) from 48-hour continuous ambulatory electrocardiogram (aECG) monitoring. Methods: The study population includes 716 black and 438 white participants from the ARIC 48-hour aECG ancillary study, after excluding those with a paced rhythm (n=43) or poor quality measures (n=8). SA was defined as self-reported physician diagnosis or hospital discharge records with ICD-9-CM codes for SA. Prevalent AF was defined using 48-hour aECG monitoring, study visit ECGs, or hospital discharge code (427.3) since study baseline in 1986-1987. PACs and PVCs were defined if ectopy was present 1-5% (occasional) and &gt;5% (frequent) of the recording time versus &lt;1% of the recording time (referent). Multivariable logistic regression was used to examine this association with inverse variance weighting to account for the sampling and non-response. Results: Participants with SA (unweighted N=217) were more likely to be female (55%), white race (52%), current smokers (57%), have hypertension (82%), and be obese (57%). Participants with SA were 7.3 (95% CI: 3.7, 14.5) times more likely to have AF compared to those without SA after adjusting for covariates. Compared to participants without SA, the relative odds of occasional and frequent PACs versus the referent was increased by 20% and 50% respectively among participants with SA after adjusting for confounders, although not statistically significant. The association was similar and not statistically significant for frequent PVCs. Conclusions: In a community-based population using standardized 48-hour aECG monitoring, SA was associated with prevalent AF, but not significantly associated with PACs or PVCs. Further study is needed to establish mechanisms that link SA and cardiac arrhythmias.

Update Ventricular Tachycardia

Idiopathic ventricular tachycardia: Frequent monomorphic premature ventricular contractions or non-sustained ventricular tachycardia without underlying structural heart disease is not a rare condition and may cause significant symptoms. A subgroup of patients develops IVT-associated cardiomyopathy. Current ESC guidelines recommend primary catheter ablation in symptomatic patients with right ventricular outflow tract IVT. Catheter ablation is also recommended in symptomatic patients with a left ventricular outflow tract (or other rare) origin, if antiarrhythmic drugs are ineffective or not desired.Ventricular tachycardia associated with structural heart disease: Scar-associated ventricular arrhythmias may cause sudden cardiac death in a variety of heart diseases. While ICD implantation has been shown to reduce mortality, repetitive ICD shocks impact on survival and quality of life. In a recent meta-analysis, both amiodarone and catheter ablation reduce the incidence of recurrent ICD shocks. Discontinuation of amiodarone due to side effects is common. Current ESC guidelines recommend both strategies (class 1 indication). Catheter ablation is also recommended in drug-resistant VT or electrical storm. A totally subcutaneous ICD is a novel option in patients not requiring pacing.

Radiofrequency catheter ablation of premature ventricular contractions in children under CARTO3 system: a retrospective study from one single center

Objective: To evaluate the clinical effect and summarize the experience of radiofrequency catheter ablation (RFCA) for children suffered from premature ventricular contractions (PVCs). Methods: This retrospective study was conducted by descriptive analysis. A total of 108 cases with frequent PVCs from Shanghai Children's Medical Center were treated with RFCA under the guidance of CARTO3 system from January 2011 to December 2016. The immediate success rate of the procedure, the recurrence rate and the perioperative complications were summarized. The constituent ratio of different PVCs origins, the trend of overall procedure time and success rate in recent years were analyzed. Statistical analyses were performed using F test. Results: Immediate success of RFCA was achieved in 104 cases (96.3%, 104/108) and 4 cases (3.7%, 4/108) failed. The PVCs recurred during follow-up of over 6 months in 5 cases (4.8%, 5/104) . There were no severe complications related to the procedure. The sites of PVCs origin, in 52 cases originated from right ventricular outflow track (48.2%, 52/108) , 17 cases originated from left ventricular outflow track (15.7%, 17/108) and 26 cases originated from tricuspid annulus (24.1%, 26/108) . Among the three predilection sites of PVCs, the operation time was (141±46) min for right ventricular outflow track, (155±50) min for left ventricular outflow track, and (166±57) min for tricuspid annulus. However, the difference was not statistically significant (F=1.79, P=0.17) . X-ray exposure time was (14±8) minutes for right ventricular outflow track ablation, (32±14) minutes for left ventricular outflow track ablation and (16±8) minutes for tricuspid annulus ablation respectively. The exposure time for the ablation on left ventricle was significantly longer than the other two sites (F=5.12, P=0.018) . Conclusion: RFCA is safe and effective for PVCs in children with high success rate and low recurrence and complication rates.

Is There any Relationship Between Myocardial Repolarization Parameters and the Frequency of Ventricular Premature Contractions?

BackgroundVentricular premature contractions (VPCs) may trigger lethal ventricular arrhythmias in patients with structural heart disease. However, this role of VPCs in healthy people remains controversial once that not enough clinical trials are available. Recently, some myocardial repolarization markers, such as Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios, have been reported to be useful for predicting lethal ventricular arrhythmias in various clinical disorders without structural heart disease.ObjectiveIn this study, we aimed to investigate the relation between VPC frequent and myocardial repolarization markers in individuals without structural heart disease.MethodsThis study included 100 patients who had complaints of dizziness and palpitations. Twelve-lead electrocardiography and 24-hour ambulatory Holter recordings were obtained from all patients. VPC burden was calculated as the total number of VPCs divided by the number of all QRS complexes in the total recording time. P-values < 0.05 were considered significant.ResultsTp-e interval and Tp-e/QTc ratio were significantly higher in patients with higher VPC burden than in patients with lower VPC burden, and a positive correlation was found between these markers and VPC burden. Tp-e (β = 1.318, p = 0.043) and Tp-e/QTc (β = -405.136, p = 0.024) in the lead V5 were identified as independent predictors of increased VPC burden.ConclusionsTp-e interval and Tp-e/QTc ratio increased in patients with high VPC number. Our study showed that VPCs may have a negative effect on myocardial repolarization. This interaction may lead to an increased risk of malignant arrhythmias.