Frequent Ventricular Premature Beats Research Articles

Cardiac Resynchronization Therapy–Defibrillator Implantation with Shock Lead Placement in the Left Bundle Branch Area by Reshaping Steerable Delivery Sheath: A Case Report

Abstract Background There are few reports of establishing cardiac resynchronization therapy-defibrillator with placing a shock lead directly into the LBBA. Case summary A 76-year-old woman with heart failure due to dilated cardiomyopathy presented to our cardiovascular medicine department. Despite receiving optimal medical therapy, she had New York Heart Association class III heart failure. While her electrocardiogram showed a sinus rhythm with a left bundle branch block pattern (QRS duration, 160 ms) and left ventricular ejection fraction of 21.0%, holter monitoring revealed frequent multifocal ventricular premature beats and non-sustained ventricular tachycardia. Owing to worsening heart failure symptoms, cardiac resynchronization therapy (CRT)-D implantation was performed. As the Agilis HisPro catheter has two 90° deflections, we reshaped its proximal part to the second deflection and added a septal curve, allowing us to screw the shock lead deep into ventricular septum and achieve QRS narrowing of right ventricular pace (114 ms). The time from stimulus to left ventricular activation was 84 ms. Coronary sinus and right atrial leads were placed in conventional manner. Finally, a defibrillation threshold test confirmed a successful treatment with no postoperative adverse events. Discussion Combining left bundle branch area pacing (LBBAP) with coronary sinus (CS) pacing improved prognosis by achieving superior electrical resynchronisation (left bundle branch–optimized CRT: LOT-CRT). However, in the absence of suitable tool for directly placing the shock lead in left bundle branch area (LBBA), it was difficult to establish LOT-CRTD. Herein, we established LOT-CRTD by reshaping Agilis HisPro catheter, which enabled shock lead placement in LBBA.

Postextrasystolic repolarization changes of ventricular premature beats correlate with structural heart disease and suggest prognostic implications

Ventricular premature beats (VPBs) can potentially lead to life-threatening arrhythmias, especially in patients with structural heart disease (SHD). However, identifying dangerous VPBs has always been a topic and challenge in clinical research. This study aimed to evaluate the relationship of postextrasystolic repolarization changes of VPBs with SHD and its possible additional prognostic value. 125 cases of frequent VPBs with SHD and 156 cases without SHD were included. VPBs were stratified selected from 24 h Holter recording according to the scale of heart rate. Average QTDV (difference value of QT interval between the first beat follow VPB with beats preceding VPB) and max QTDV were significantly longer in SHD group than that in the non-SHD group. For identifying patients with SHD, the best cutoff value were 19 ms for average QTDV (AUC = 0.931) and 29 ms for max QTDV (AUC = 0.910) respectively. For Tu morphology analysis, PT2 (postextrasystolic T wave amplitude change ≥2 mV), reversed T wave, and Pu (postextrasystolic u wave) change were all highly specific, but low sensitive as identification of SHD. Compared with average QTDV < 19 ms patients, average QTDV ≥ 19 ms patients had significantly larger left heart size and wores left cardiac function. The presence of non-persistent ventricular tachycardia runs was higher in average QTDV ≥ 19 ms group and positive Pu change group than that in control groups. The findings indicated that postextrasystolic repolarization changes of VPBs correlated with SHD and suggested potential value in prognosis asssessment.

Genetic characterization of drug-induced long QT syndrome in a large prospective cohort

Abstract Introduction Drug-induced long QT syndrome (DI-LQTS) is a clinical entity with a poorly defined etiopathogenesis. Purpose The objective of the study was to determine the genetic basis of a prospective cohort of patients with DI-LQTS in the setting of a tertiary hospital center. Methods Prospective observational study with consecutive inclusion of patients with the diagnosis of DI-LQTS according to standard criteria, in a tertiary hospital, between 2018 and 2022. A genetic study was performed through massive DNA sequencing to identify variants in known genes associated with cardiopathy, arrhythmogenic and cardiomyopathy. Results 86 patients (age 65±15 years, 59% men) were included. The mean corrected QT interval (QTc) of the entire cohort was 543±56 ms. The drugs associated with QTc interval prolongation were: psychotropics 51%, antiarrhythmics 38%, anesthetics 30%, antibiotics 16%, antineoplastics 5%, others 4%. Twenty-one patients (24%) presented with ventricular arrhythmias at the time of drug-induced QTc prolongation: 10 (12%) ventricular fibrillation, 7 (8%) sustained ventricular tachycardia, 3 (3%) non-sustained ventricular tachycardia, 1 (1%) frequent ventricular premature beats. Genetic information was obtained in 83 (97%) patients. 17 pathogenic mutations associated with heart disease were identified in 15 (18%) patients: 4 (5%) patients with 5 mutations in ion channel genes (KCNE1, KCNE1B, KCNH2, RYR1, RYR2), and 12 (14%) patients with 12 mutations in genes associated with cardiomyopathy (NF1, PKD2, ABCC6, TTN, FHOD3, MYO6, COL11A1, CCDC40, CRELD1, COL4A1). Two patients had 2 pathogenic mutations each, one of them with both mutations associated with channelopathy, and another with a mutation associated with channelopathy and a second mutation related to cardiomyopathy. Only 1 patient carrying a pathogenic mutation related to cardiomyopathy had a clear phenotype, while in 3 carrier patients there was a history of transient systolic dysfunction, 2 due to tachycardiocardiopathy and 1 due to peripartum cardiomyopathy. The identification of a pathogenic mutation was not related to significant differences in QTc interval prolongation (544±63 vs 542±55 ms) or risk of ventricular arrhythmias (26% vs 24%). Conclusions The genetic basis of drug-induced long QT syndrome is essentially different from that of the congenital form of the disease. The identification of pathogenic mutations in genes associated with cardiomyopathy is relatively frequent, while those associated with ion channel genes are uncommon.

Safety and efficacy of a temperature-controlled ablation system for ventricular tachycardia: first results from the TRAC-VT study

Abstract Background Catheter ablation using radiofrequency (RF) energy, is a well-recognized treatment option for patients with ventricular arrhythmias. However, procedural complications may be high, and efficacy is often suboptimal with high recurrence rates. Purpose The TRAC-VT study evaluated safety and efficacy of the DiamondTemp Ablation (DTA) System for the treatment of patients with ventricular arrhythmias by catheter ablation. Methods A temperature-controlled, irrigated RF catheter (with six thermocouples and an internal network of diamond coatings) was utilized to treat subjects with either sustained monomorphic ventricular tachycardia (VT) and structural heart disease or with frequent monomorphic symptomatic ventricular premature beats (VPBs) and normal hearts. Patients were enrolled at five hospital centers in five European countries and were followed for 6 months. Ablation was performed in temperature-control mode with an irrigation flow of 8 mL/min for all power deliveries. The target temperature was set to 55 or 60 °C with a power output limited to 50 Watts. RF energy was applied for a maximum of 45 seconds per target site, depending on impedance drop and electrogram abatement. Results The study enrolled 49 subjects (age 67±12 years, 80% male) in total (38 with sustained monomorphic VT and structural heart disease and 11 with symptomatic VPBs). In all cases, mapping and navigation was used with EnSite systems (Abbott). The average ablation time (defined as time from the insertion of the DTA catheter until removal from body) was 87 ± 44 minutes. During this time, RF energy was applied for an average of 28.2 ± 10.2 seconds with a power of 44.0 ± 7.0 W and a temperature of 50.9 ± 3.9 °C during 35.0 ± 23.2 applications. Acute procedural success was 100% (93%-100%), and it was defined as the elimination of VPBs or non-inducibility for sustained VT (using solely the DTA catheter). The primary safety procedure-related endpoint was an evaluation of cardiovascular-related death, stroke / TIA, cardiac tamponade/perforation, bleeding complication, myocardial infarction, thromboembolism, and pulmonary edema. In total review of the primary safety endpoint, one subject had a confirmation of a stroke / TIA event. Regarding longer term procedural efficacy, the 6-month follow-up was completed in 92% of subjects. For the whole study population chronic success from recurrence of ventricular arrhythmia (faster than 100 beats/min after 6 months) was 73.4% (58.6%-83.6%) for non-sustained ventricular arrhythmias (≥3 beats) and 87.7% (74.7%-94.3%) for sustained ventricular arrhythmias (≥30 sec). Conclusions VT/VPBs ablation using a temperature-controlled irrigated RF catheter was safe and effective with low VT recurrence at 6 months of follow-up.

A Case Report of Arrhythmia Caused by Skin Expander Implantation

A 51-year-old female patient suffered facial burns during her youth. Following the healing of the wound, a skin expander was implanted on 7 December 2021 to address scar contracture. The preoperative electrocardiogram (ECG) indicated sinus rhythm within the normal range. Color Doppler ultrasound revealed no abnormalities. The patient had no history of hypertension, heart disease, diabetes, arrhythmia, or other cardiovascular and cerebrovascular conditions. On 16 June 2022, the skin expander was removed, and facial scar resection was performed. The routine ECG showed ventricular premature beats. During the operation, when the surgeon pulled and compressed the neck dilator, significant arrhythmia was observed, with the heart rate dropping below 50 beats per minute and frequent ventricular premature beats occurring. The surgeon promptly halted the procedure, resulting in immediate relief of the patient's pain. Subsequently, the ventricular premature beats ceased, and normal sinus rhythm was restored. Once the heart rate exceeded 60 beats per minute, the surgeon resumed the operation, but ventricular premature beats persisted. After removing the dilator, the heart rate gradually returned to normal, and no further arrhythmia occurred. The patient recovered smoothly post-operation, with stable vital signs and no reported discomfort. She safely returned to the ward. It was determined that the patient's arrhythmia was caused by the compression of the carotid sinus due to the stretching of the neck dilator.

Nicotine Formulation Influences the Autonomic and Arrhythmogenic Effects of Electronic Cigarettes.

Evidence is mounting that electronic cigarette (e-cig) use induces cardiac sympathetic dominance and electrical dysfunction conducive to arrhythmias and dependent upon nicotine. A variety of nicotine types and concentrations are available in e-cigs, but their relative cardiovascular effects remain unclear. Here we examine how different nicotine forms (racemic, free base, and salt) and concentrations influence e-cig-evoked cardiac dysfunction and arrhythmogenesis and provide a mechanism for nicotine-salt-induced autonomic imbalance. ECG-telemetered C57BL/6J mice were exposed to filtered air (FA) or e-cig aerosols from propylene glycol and vegetable glycerin solvents either without nicotine (vehicle) or with increasing nicotine concentrations (1%, 2.5%, and 5%) for three 9-minute puff sessions per concentration. Spontaneous ventricular premature beat (VPB) incidence rates, heart rate, and heart rate variability (HRV) were compared between treatments. Subsequently, to test the role of β1-adrenergic activation in e-cig-induced cardiac effects, mice were pretreated with atenolol and exposed to either FA or 2.5% nicotine salt. During puffing and washout phases, ≥2.5% racemic nicotine reduced heart rate and increased HRV relative to FA and vehicle controls, indicating parasympathetic dominance. Relative to both controls, 5% nicotine salt elevated heart rate and decreased HRV during washout, suggesting sympathetic dominance, and also increased VPB frequency. Atenolol abolished e-cig-induced elevations in heart rate and declines in HRV during washout, indicating e-cig-evoked sympathetic dominance is mediated by β1-adrenergic stimulation. Our findings suggest that inhalation of e-cig aerosols from nicotine-salt-containing e-liquids could increase the cardiovascular risks of vaping by inducing sympathetic dominance and cardiac arrhythmias. Exposure to e-cig aerosols containing commercially relevant concentrations of nicotine salts may increase nicotine delivery and impair cardiac function by eliciting β1-adrenoceptor-mediated sympathoexcitation and provoking ventricular arrhythmias. If confirmed in humans, our work suggests that regulatory targeting of nicotine salts through minimum pH standards or limits on acid additives in e-liquids may mitigate the public health risks of vaping.

An Early Indicator in Evaluating Cardiac Dysfunction Related to Premature Ventricular Complexes: Cardiorespiratory Capacity.

Cardiac dysfunction induced by premature ventricular complexes (PVCs) is relatively controversial and challenging to detect in the early stage. In this observational study, we retrospectively analyzed the cardiopulmonary exercise test (CPET) data of 94 patients with frequent premature ventricular beats (47 males, 49.83 ± 13.63 years) and 98 participants (55 males, 50.84 ± 9.41 years) whose age and gender were matched with the patient with PVCs. The baseline information and routine echocardiography detection were recorded on admission. PVCs were diagnosed by 24 h Holter monitoring, and cardiorespiratory capacity was assessed using peak oxygen uptake (V'O2peak), anaerobic threshold (AT), and other CPET parameters with an individualized bicycle ramp protocol according to the predicted workload and exercise situation of each participant. There were no statistically significant differences in most baseline characteristics between the two groups. Indicators that reflect cardiopulmonary capacity, such as V'O2peak, AT, and ΔO2 pulse/Δwork rate(ΔV'O2/ΔWR), were all significantly lower in the PVC group (p = 0.031, 0.021, and 0.013, respectively) despite normal and nondiscriminatory left ventricular ejection fractions between the two groups. However, there was no statistically significant difference among subgroups based on the frequency of PVCs, which was <10,000 beats/24 h, 10,000-20,000 beats/24 h, and >20,000 beats/24 h. The cardiorespiratory capacity was lower in patients with frequent PVCs, indicating that CPET could detect early signs of impaired cardiac function induced by PVCs.

Inflammation of conduction tissue is a major determinant of electrical instability in patients with arrhythmic phenotype of myocarditis

Abstract Background Arrhythmic presentation of myocarditis can be life-threatening although often associated with a preserved cardiac dimension and function. The involvement of conduction tissue (CT) has been suggested as pro-arrhythmic factor, but its role has not conclusively supported. Purpose CT inflammation in myocarditis with arrhythmic presentation. Methods We retrospectively enrolled consecutive patients from January 2010 to June 2021 with acute myocarditis (&amp;lt; 1 month from the onset of symptoms). Patients were categorized according to clinical presentation in arrhythmic [frequent premature ventricular beats, non-sustained or sustained ventricular tachycardia (VT) and survivors of ventricular fibrillation, associated to preserved cardiac contractility –LVEF ≥ 50%] (Group A) and cardiomyopathy phenotype (signs and symptoms of heart failure with LVEF≤ 45%) (Group B). All patients had a normal coronary network at angiography and an unremarkable valvular pattern at 2D-Echo.They all underwent a LV endomyocardial biopsy; sections of CT (Purkinje fibres) were identified by morphologic (Ashoff and Monkeberg criteria) findings and positive immunohistochemistry for HCN4. CT infiltration was demonstrated by the presence of CD45Ro+ T lymphocytes and the necrosis of adjacent small and loosely arranged myocytes. The extent of myocardial fibrosis, the rate of vasculitis and CT inflammation was compared between the two groups. Results Among 217 consecutive pts with biopsy-proven diagnosis of myocarditis, 107 (49.3%) had an arrhythmic presentation (Group A). CT was observed in 33 (30.8%) patients in the Group A and 31 (28.2%) of Group B. In patients with biopsy-evidence of CT, no significant difference was reported in the mean age (51.2±16.8 vs 53.7±14.7; p-value: 0.53) . Inflamed CT was documented in 2 (6.5%) cases in Group B and in 33 (100%) in Group A (p-value&amp;lt; 0.001). No statistically difference was observed between Group A and B regarding the presence of vasculitis (4 vs 1; p-value: 0.36) and myocardial fibrosis (8.8±4.2% vs 9.5±4.3%; p-value: 0.50). Conclusion CT inflammation is a major determinant of electrical instability in human myocarditis with arrhythmic presentation. Figure Legend Sustained ventricular tachycardia (A) associated to severe infiltration by CD45Ro T lymphocytes of CT in an acute myocarditis with arrhythmic presentation.

P324 LEFT VENTRICULAR ISOLATED CARDIOMYOPATHY OR DILATED CARDIOMYOPATHY: THE ROLE OF GENETIC ANALYSIS

Abstract Introduction arrhytmogenic cardiomyopathy (ACM) is a genetic heart muscle disease caracterized by substitution of the ventricular myocardium with fibrofatty tissue. The disease was originally termed “arrhytmogenic right ventricular (dysplasia)/cardiomyopathy” to define a condition which distinctively affected the right ventricle and predisposed to fatal ventricular arrhythmias. New insights led to comprehending that the left ventricle is also frequently affected. Clinical case 62 yo, male, no cardiovascular risk factors, positive history for frequent ventricular premature beats treated with Sotalol 40 mg twice a day. No other previous cardiological events. Accesses the ER with suddenly occured dyspnea for minimal exertion, without palpitation, chest discomfort or loss of consciousness. EKG: synus rhythm, low voltages, negative V4–V6 T waves, fragmented QRS. Blood testing: TnI 0,532 ng/ml (n.v. 0–0.034) NTproBNP 3840. Echocardiography: dilated left ventricle. 20% EF due to infero–lateral wall akynesia. Coronary angiography was performed and showed no coronary stenosis. Considered the frequent NSVTs showed by the telemetry, he was admitted to ICU and treated with Amiodarone, Atenolol 100 mg, Sacubistril/Valsartan 24/26 mg, diuretic therapy showing good control of major arrhytmic events. To evaluate characterize heart tissue, a magnetic resonance was performed, which showed: scalloping of the mid and apical left ventricular lateral wall, with fibrofatty substitution. Subepicardial, mid–wall and transmural LGE of the LV anterior, lateral and inferior walls. No RV abnormalities. Considered the reduced EF and the presence of arrhytmic substratum, an ICD was implanted. Finally, a genetic evaluation was discussed with the patient, but was declined. Discussion in patients presenting with typical LV abnormalities, without RV involvement, the phenotipic Padua criterias are not enough for a certain diagnosis. This is because of the phenotipic overlap between ACM and other diseases, such as dilated cardiomyopathy, myocarditis and cardiac sarcoidosis. In the presence of LV involvement, consistent with ACM, the evidence of a pathogenetic mutation is key for the diagnosis.

PO-04-090 2 HIT WONDER: AUTOSOMAL RECESSIVE-CPVT WITH CONDUCTION DISEASE

Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is a primary arrhythmogenic syndrome with clinical manifestations of syncope and sudden death following exercise or agitation. Present familial cases of autosomal recessive CPVT due to homozygous variants in RYR2 with associated conduction disease. The case was reviewed in detail as below. A 14 year-old girl presented following out of hospital cardiac arrest at a trampoline park. AED strip demonstrated ventricular fibrillation that terminated to sinus rhythm with electrical cardioversion. Workup was notable for a resting ECG with a rate of 52 bpm, a PR of 238 and a right bundle branch block with a QRS duration of 145ms . Exercise stress test resulted in frequent premature ventricular beats and bidirectional couplets. Genetic testing demonstrated homozygosity of a novel VUS in RYR2 (c.9392A>C (p.Tyr3131Ser)). Analysis by REVEL demonstrated a score of (0.763), predicting pathogenicity. Parents were found to be heterozygous asymptomatic carriers of the same variant and one sibling was homozygous for the variant. This sibling had a prolonged PR interval and intraventricular conduction delay and was phenotypically positive during exercise stress test. Two siblings who were heterozygous for the variant had normal ECG and exercise stress tests. The proband was started on nadalol and flecainide and a dual chamber ICD was placed for secondary prevention and significant sinus bradycardia prior to initiation of antiarrhythmics. On follow up EST the patient was noted to have acute onset high grade AV block during exercise resulting in initiation of ventricular pacing as well as runs of atrial tachycardia. Baseline ECG did not demonstrate QRS widening and flecainide level was within limits. The affected sibling was started on nadolol. We report two cases of patients homozygous for a VUS in RYR2 manifesting phenotypically as CPVT with associated conduction disease. Further study of this distinct phenotype of CPVT is warranted.

A New Scoring System for Predicting Ventricular Arrhythmia Risk in Patients with Acute Myocardial Infarction.

In this study, a risk score for ventricular arrhythmias (VA) were evaluated for predicting the risk of ventricular arrhythmia (VA) of acute myocardial infarction (AMI) patients. Patients with AMI were divided into two sets according to whether VA occurred during hospitalization. Another cohort was enrolled for external validation. The area under the curve (AUC) of receiver operating characteristic (ROC) was calculated to evaluate the accuracy of the model. A total of 1493 eligible patients with AMI were enrolled as the training set, of whom 70 (4.7%) developed VA during hospitalization. In-hospital mortality was significantly higher in the VA set than in the non-VA set (31.4% vs 2.7%, P=0.001). The independent predictors of VA in patients with AMI including Killip grade ≥3, STEMI patients, LVEF <50%, frequent premature ventricular beats, serum potassium <3.5 mmol/L, type 2 diabetes, and creatinine level. The AUC of the model for predicting VT/VF in the training set was 0.815 (95% CI: 0.763-0.866). A total of 1149 cases were enrolled from Xuzhou Center Hospital as the external validation set. The AUC of the model in the external validation set for predicting VT/VF was 0.755 (95% CI: 0.687-0.823). Calibration curves indicated a good consistency between the predicted and the observed probabilities of VA in both sets. We have established a clinical prediction risk score for predicting the occurrence of VA in AMI patients. The prediction score is easy to use, performs well and can be used to guide clinical practice.

CARDIAC PROTECTION THERAPY CAN PREVENT THE ELEVATION OF CENTRAL BLOOD PRESSURE IN ADULT PATIENTS WITH CONGENITAL HEART DISEASE

Objective: There is no evidence of beneficial effect of cardiac protection (CP) therapy for heart failure, that is medication of renin-angiotensin system antagonists and beta blockers, in patients with congenital heart disease (CHD). However, these drugs have blood pressure (BP) lowering effect and may prevent future hypertension in CHD patients, who are high risk for hypertension. Therefore, we examine the BP lowering effect of CP in adults with CHD. Design and method: We enrolled 131 consecutive subjects aged &gt; 20 years who visited the Department of Adult Congenital Heart Disease, Chiba Cardiovascular Center. The exclusion criteria were as follows: (1) a history of atrial fibrillation or frequent supra or ventricular premature beats, (2) history of cardiac operation in the past 6 months, (3) medication for hypertension, and (4) NYHA II-IV. We divided the remaining 60 patients into cardiac protection (+) and (-) and compared their brachial and central systolic BP (SBP). We defined a patient whose brachial SBP was higher than 1SD of age and sex matched control (Japanese general population) as high SBP. Moreover, we defined a patient whose central SBP was higher than 1SD of control as high central SBP. Results: Fifteen patients were medicated CP drugs (carvedilol 7, bisoprolol 1, enalapril 11, candesartan 2) (CP+). The mean age was 34.1 ± 13.2 years in CP- and 30.3 ± 11.4 in CP+. The brachial systolic/diastolic BP was 124.4 ± 19.7/74.6 ± 14.0 mmHg in CP- 116.7 ± 12.5/66.2 ± 12.1 mmHg in CP+. There were 14 high SBP patients in CP- and one patient in CP+ (p = 0.0535). The central SBP was 126.8 ± 21.0 mmHg in CP- and 113.2 ± 16.0 mmHg in CP+. There were 16 high central CBP patients in CP- and one patient in CP+ (p = 0.0043). Conclusions: The number of high central SBP in patients with CP+ was smaller than CP-. It may be obvious because the drugs used for CP have BP lowering effect. It is well known that hypertension is popular in patients with CHD. CP drugs for heart failure may prevent future cardiovascular disease in patients with CHD.

Straight back syndrome and frequent ventricular premature beats.

Straight back syndrome and frequent ventricular premature beats.

Newer Methods for Ventricular Tachycardia Ablation and When to Use Them.

Radiofrequency (RF) catheter ablation has long been an important therapy for ventricular tachycardia and frequent symptomatic premature ventricular beats and nonsustained arrhythmias when antiarrhythmic drugs fail to suppress the arrhythmias. It is increasingly used in preference to antiarrhythmic drugs, sparing the patient adverse effects of drugs. Success of ablation varies with the underlying heart disease and type of arrhythmia: very effective for patients without structural heart disease, less effective in structural heart disease. Failure occurs when a target for ablation cannot be identified or ablation lesions fail to reach and abolish the arrhythmia substrate that may be extensive, intramural, or subepicardial in location. Approaches to improving ablation lesion creation are modifications to RF ablation and emerging investigational techniques. Easily- implemented modifications to RF methods include manipulating the size and location of the cutaneous dispersive electrode, increasing duration of RF delivery, and use of lower-tonicity catheter irrigation (usually 0.45% saline). When catheters can be placed on either side of culprit substrate, RF can be delivered in a bipolar or simultaneous unipolar configuration that can be successful. Catheters with extendable and retractable irrigated needles for delivery of RF are under investigation in clinical trials. Cryoablation is potentially useful with specific situations in which maintaining contact is difficult. Transvascular ethanol ablation and stereotactic radioablation have both shown promise for arrhythmias that fail other ablation strategies. Although substantial clinical progress has been achieved, further improvement is clearly needed. With ability to increase ablation lesion size, continued careful evaluation of safety, which has been excellent for standard RF ablation, remains important.

438 Appearances are deceiving

Abstract Aims Mitral valve prolapse (MVP) is frequently found in the population (3% prevalence). MVP prognosis is generally benign; however, malignant arrhythmias and increased risk of arrhythmic sudden cardiac death (0.2% to 0.4% per year) was described in patients, usually female, mostly affected by bileaflet myxomatous disease, mid-systolic click, ripolarization abnormalities in the inferior leads, and complex ventricular arrhythmias with polymorphic/right bundle branch block morphology, without significant regurgitation. The actual burden, risk stratification, and treatment of the so-called arrhythmic MVP are unknown. Methods Z.T. is a 32 years old woman who was admitted to the Emergency Department (ED) with left arm and face paraesthesia. She also reported having suffered from migraine and hypertension a few days earlier. ECG: normal sinus rhythm, no ripolarization abnormalities. CT and MRI were executed to rule out cerebral ischaemic events and both resulted negative. No SCD was reported in the anamnesis and the patient denied syncopal and pre-syncopal episodes. Z.T. had undergone cardiologic examination for tachycardia 2 years before the present events, during her second pregnancy (she produced no documentation to this effect). No chronic therapy. Low blood pressure at home. Due to the patient’s cardiologic history, ECG monitoring was performed, evidencing frequent premature ventricular beats (PVBs), some couples, and triplets. Cardiologic evaluation was requested. On Echocardiogram: Normal bi-ventricular function. Bileaflet mitral valve prolapse with myxomatous degeneration. Minimal valve regurgitation. Mitral annulus disjunction. TE echocardiogram: no PFO. Nadolol 20 mg was prescribed and after 24 h of observation the patient was discharged, scheduling Holter ECG, cardiac MRI and arrhythmologic evaluation. Results One month later, the patient reported intolerance to nadolol due to hypotension and pre-syncopal episodes during postural changes. Holter ECG revealed: polymorphic PVBs (2009), couples (383), triplets (40). Cardiac MRI: mitral valve prolapse (11 mm), mitral annulus disjunction (8mm) systolic curling (3mm). No LGE. No oedema. Nadolol was discontinued and substituted with bisoprolol 2.5 mg. Physical activity was discouraged; Ergometric test and Holter ECG were ordered under treatment with bisoprolol. The Ergometric test revealed reduced extrasystolia during physical effort, isolated PVBs and some couples during recovery. Holter ECG revealed continuing isolated PVBs (980) and some couples (37). No complex arrhythmia. Conclusion Z.T. is affected by an arrhythmic MVP syndrome characterized by complex PVBs, mitral annular disjunction, and systolic curling, which have been described by pathological and cardiac magnetic resonance studies in sudden death victims. However, Z.T. is asymptomatic: no ECG ripolarization abnormalities at rest and good response to medical therapy with β-blockers. Our patient strategy was conservative and we decided to follow up with trimestral cardiologic evaluation and Holter ECG. Further research is needed to best identify high-risk patients and suggest treatments aimed to prevent sudden death.

Arrhythmogenic right ventricular cardiomyopathy associated with arrhythmia-induced cardiomyopathy: A case report

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a kind of inherited cardio-myopathy, which is characterized by fibro-fatty replacement of right ventricular myocardium, leading to ventricular arrhythmia. However, rapid atrial arrhythmias are also common, including atrial fibrillation, atrial flutter and atrial tachycardia. Long term rapid atrial arrhythmia can lead to further deterioration of cardiac function. This case is a 51-year-old male. He was admitted to Department of Cardiology, Peking University Third Hospital with palpitation and fatigue after exercise. Electrocardiogram showed incessant atrial tachycardia. Echocardiography revealed dilation of all his four chambers, especially the right ventricle, with the left ventricular ejection fraction of 40% and the right ventricular hypokinesis. Cardiac magnetic resonance imaging found that the right ventricle was significantly enlarged, and the right ventricular aneurysm had formed; the right ventricular ejection fraction was as low as 8%, and the left ventricular ejection fraction was 35%. The patients met the diagnostic criteria of ARVC, and both left and right ventricles were involved. His physical activities were restricted, and metoprolol, digoxin, spironolactone and ramipril were given. Rivaroxaban was also given because atrial tachycardia could cause left atrial thrombosis and embolism. His atrial tachycardia converted spontaneously to normal sinus rhythm after these treatments. Since the patient had severe right ventricular dysfunction, frequent premature ventricular beats and non-sustained ventricular tachycardia on Holter monitoring, indicating a high risk of sudden death, implantable cardioverter defibrillator (ICD) was implanted. After discharge from hospital, physical activity restriction and the above medicines were continued. As rapid atrial arrhythmia could lead to inappropriate ICD shocks, amiodarone was added to prevent the recurrence of atrial tachycardia, and also control ventricular arrhythmia. After 6 months, echocardiography was repeated and showed that the left ventricle diameter was reduced significantly, and the left ventricular ejection fraction increased to 60%, while the size of right ventricle and right atrium decreased slightly. According to the clinical manifestations and outcomes, he was diagnosed with ARVC associated with arrhythmia induced cardiomyopathy. According to the results of his cardiac magnetic resonance imaging, the patient had left ventricular involvement caused by ARVC, and the persistent atrial tachycardia led to left ventricular systolic dysfunction.

Combination of arrhythmogenic right ventricular dysplasia with left ventricular non-compaction as a special form of cardiomyopathy: clinic, diagnostics, genetic, natural course

Abstract Background A few cases of combination of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) with left ventricular noncompaction (LVNC) have been described. Aims To study the genetics, diagnostical features and clinical course of the combination of ARVC with LVNC. Materials and methods 58 patients with ARVC diagnosis (26 men; mean age 39.1±14.2 years; mean follow-up period – 21.5 [6; 60] months) and 125 patients with LVNC (74 men; mean age 46.4±15.1 years; mean follow-up period – 14 [3; 40] months). All patients underwent electrocardiogram (ECG), echocardiography, 24-h ECG monitoring. Heart MRI was performed in 53 (91.4%) patients with ARVC and 60 (48%) with LVNC, heart CT – in 18 (31%) patients with ARVC and 89 (71.2%) with LVNC. For all patients with combination of ARVC and LVNC DNA-diagnostic was performed using both ARVC (PKP2, DSG2, DSP, DSC2, JUP, TMEM43, TGFB3, PLN, LMNA, DES, CTTNA3, EMD, SCN5A, LDB3, CRYAB, FLNC) and LVNC (MYH7, MYBPC3, TAZ, TPM1, LDB3, MYL2, MYL3, ACTC1, TNNT2, TNI3) gene panels. Results Combination of ARVC and LVNC was found in 9 patients (15.5% of patients form ARVC cohort and 7.2% from LVNC cohort). These patients were distinguished from patients with isolated ARVC or LVNC by aggressive ventricular arrhythmias (frequent premature ventricular beats, sustained ventricular tachycardia, significantly worse antiarrhythmic therapy effect, appropriate shocks of implanted cardioverter-defibrillators (ICD) in all patients with ICD). Patients with combination of ARVC+LVNC were also distinguished from patients with isolated LVNC by the dilatation of RV, low QRS voltage on ECG, presence of AV block, absence of signs of LV hypertrophy on ECG. LV dilatation with reduction of its ejection fraction distinguished patients with mixed cardiomyopathy from patients with isolated ARVC. Potentially pathogenic variants (IV-V classes of pathogenicity) and variants of unclear clinical significance (III class of pathogenicity) were found in both desmosomal and non-desmosomal genes in 78% of patients, including 3 (33%) in DSP gene. Conclusions The combination of ARVC and LVNC can be caused by mutations in both desmosomal and non-desmosomal genes and has typical features: aggressive, resistant ventricular rhythm abnormalities leading to appropriate ICD shocks and a high risk of sudden cardiac death. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Genetic testing of patients was supported by Grant No. 16-15-10421 of the Russian Science Foundation

Characterisation of ventricular premature beats during exercise testing in masters athletes

Abstract Background Exercise induced ventricular premature beats (VPBs) are associated with an adverse outcome in patients with cardiac disease and the general population. The incidence and significance of exercise induced VPBs in masters athletes remains unknown. Methods 237 masters athletes (54.6±8 years of age, 42% male) and 50 controls of similar age and sex were assessed with a 12-lead ECG, echocardiogram, cardiopulmonary exercise test, 24-hour holter, cardiovascular magnetic resonance imaging and a CT coronary angiogram. Athletes had participated in endurance exercise for a meanof 32±12 years. Results Athletes achieved a higher VO2 max (43.2 ml/min/kg vs 28 ml/min/kg) compared with controls and on average weighed 12kg less (63kg vs 75kg). VPBs were common in master athletes during exercise but are no more common than in age matched sedentary controls (39.3% vs 33.3% &amp;gt;1 VPB, and 8.9% vs 5.9% complex or frequent VPBs). There were no sex differences in terms of VPB number (40% vs 39%) or complex morphology (10% vs 8%) between male and female athletes. Athletes demonstrating complex ectopy during ETT had similar age (54.8±9 and 54.6±8), years of competition (34±9 and 32±12), VO2 max (40±6 and 43±7ml/min/kg), left ventricular mass (142±36g and 148±35g), end diastolic volume (160±35ml and 157±32ml) and incidence of late gadolinium enhancement (14% and 10%) compared with athletes who did not reveal complex VPBs. Conclusion VPBs are common during exercise testing in both masters athletes and sedentary age matched controls. Exercise-induced complex ectopy in an asymptomatic, low risk masters athlete represents a poor marker of significant structural heart disease. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Cardiac Risk in the Young

Coronary artery branch misinterpreted as pathological septal late gadolinium enhancement: a common pitfall during evaluation of athletes with ventricular arrhythmias.

Cardiac magnetic resonance (CMR) is increasingly prescribed in sport cardiology during pre-participation screening. Common indications are electrocardiography abnormalities, rhythm disturbances, cardiovascular symptoms like syncope, family history for hereditary cardiomyopathy or sudden death, which are all conditions that increase the likelihood of underlying cardiac disease at risk of arrhythmic events with exercise. However, despite its unique capability of tissue characterization and accurate thickness, volume, and function estimation, CMR can be prone to false-positive findings, especially during late gadolinium enhancement (LGE) assessment, leading to cardiac disease overdiagnosis and inappropriate disqualification from competitive sports activity. Herein, we report the case of a 45-year-old male middle distance runner, who came to our attention for frequent premature ventricular beats. Arrhythmias had a prevalent right bundle branch morphology and showed a mild worsening in amount and complexity during effort. Echocardiogram was unremarkable. Conversely, the CMR post-contrast images detected a mid-wall hyperintense signal on basal interventricular septum,...

Performance of a novel ECG criterion for improving detection of left ventricular hypertrophy: a cross-sectional study in a general Chinese population

ObjectivesThe sensitivity of ECG for detecting left ventricular hypertrophy (LVH) is low. The aim of this study was to explore a better ECG criterion for screening LVH in a large...