Frequent Ventricular Ectopic Beats Research Articles

The incidence of spontaneous arrhythmias in telemetered beagle dogs, Göttingen Minipigs and Cynomolgus non-human primates: A HESI consortium retrospective analysis

IntroductionCharacterization of the incidence of spontaneous arrhythmias to identify possible drug-related effects is often an important part of the analysis in safety pharmacology studies using telemetry. MethodsA retrospective analysis in non-clinical species with and without telemetry transmitters was conducted. Electrocardiograms (24 h) from male and female beagle dogs (n = 131), Göttingen minipigs (n = 108) and cynomolgus non-human primates (NHP; n = 78) were analyzed. ResultsVentricular tachycardia (VT) was observed in 3% of the dogs but was absent in minipigs and NHPs. Ventricular fibrillation (VF) was not observed in the 3 species. Ventricular premature beats (VPBs) were more frequent during daytime and atrioventricular blocks (AVBs) were more frequent at night in all species. A limited number of animals exhibited a high arrhythmia frequency and there was no correlation between animals with higher frequency of an arrhythmia type and the frequency of other arrythmias in the same animals. Clinical chemistry or hematology parameters were not different with or without telemetry devices. NHP with a transmural left ventricular pressure (LVP) catheter exhibited a greater incidence of VPBs and PJCs compared to telemetry animals without LVP. DiscussionAll species were similar with regards to the frequency of ventricular ectopic beats (26–46%) while the dog seemed to have more frequent junctional complexes and AVB compared to NHP and minipigs. Arrhythmia screening may be considered during pre-study evaluations, to exclude animals with abnormally high arrhythmia incidence.

P57 SPONTANEOUS DISSECTION OF THE DISTAL MARGINAL BRANCH IN A YOUNG WOMAN IN THE PERIPARTUM WITH NO FLOW LIMITATION AT THE PRESENTATION EVOLVED INTO SEVERE DISSECTION OF THE ANTERIOR CIRCUMFLEX AND DESCENDING ARTERY COMPLICATED BY CARDIOGENIC SHOCK

Abstract We describe the case of a 39–year–old woman with a history of recent natural birth, who came to our observation for an episode of oppressive chest pain while breastfeeding her baby at night. At the entrance, the electrocardiographic and echocardiographic findings and myocardiocitonecrosis enzymes were normal; after three hours the second enzymatic determination was clearly increased, so the patient was admitted to our ICU with a diagnosis of SCA / NSTEMI. She was therefore subjected to coronary angiography with a small hematoma in the distal tract of the marginal branch without flow limitation; it was therefore decided, in accordance with the AHA and ESC guidelines, for a conservative medical therapy. On the third day of hospitalization, the patient presented recurrence of chest pain with electrocardiographic evidence of ST segment elevation in the anterolateral site. A new angiographic evaluation was therefore performed urgently, showing a complete retrograde dissection from the marginal branch to the circumflex branch and to the anterior descending branch with TIMI 0–1 flow. During the procedure the patient underwent a prolonged hypotensive episode associated with frequent polymorphic ventricular ectopic beats, with rapid evolution towards a picture of overt cardiogenic shock. Therefore we proceeded quickly to perform PTCA with placement of medicated stents on all branches involved in the dissection, with rapid improvement of the haemodynamic picture. Spontaneous coronary dissections represent for a hemodynamist a condition of great technical difficulty where the margins of error are very high. Thanks to the technological evolution of materials, an experienced hemodynamist is able, more and more easily, to be successful in the revascularization procedure and to resolve extremely serious clinical pictures. This case report describes a spontaneous coronary dissection that most often occurs in young women in good health and without risk factors for coronary heart disease, particularly in the peripartum period. The presentation was similar to an acute coronary syndrome. According to AHA and ESC guidelines, therapy was conservative if dissection / hematoma is not a flow restriction with coronary angiography after a few days to demonstrate vessel restoration.

Left Ventricular Remodeling in Non-syndromic Mitral Valve Prolapse: Volume Overload or Concomitant Cardiomyopathy?

Mitral valve prolapse (MVP) is a common valvular disorder that can be associated with mitral regurgitation (MR), heart failure, ventricular arrhythmias and sudden cardiac death. Given the prognostic impact of these conditions, it is important to evaluate not only mitral valve morphology and regurgitation, but also the presence of left ventricular (LV) function and remodeling. To date, several possible hypotheses have been proposed regarding the underlying mechanisms of LV remodeling in the context of non-syndromic MVP, but the exact pathophysiological explanation remains elusive. Overall, volume overload related to severe MR is considered the main cause of LV dilatation in MVP. However, significant LV remodeling has been observed in patients with MVP and no/mild MR, particularly in patients with bileaflet MVP or Barlow’s disease, generating several new hypotheses. Recently, the concept of “prolapse volume” was introduced, adding a significant volume load to the LV on top of the transvalvular MR volume. Another possible hypothesis is the existence of a concomitant cardiomyopathy, supported by the link between MVP and myocardial fibrosis. The origin of this cardiomyopathy could be either genetic, a second hit (e.g., on top of genetic predisposition) and/or frequent ventricular ectopic beats. This review provides an overview of the different mechanisms and remaining questions regarding LV remodeling in non-syndromic MVP. Since technical specifications of imaging modalities impact the evaluation of MR severity and LV remodeling, and therefore might influence clinical decision making in these patients, this review will also discuss assessment of MVP using different imaging modalities.

217 Why it is important to recognize Brugada syndrome in athletes: a case report

Abstract Aims The Brugada syndrome (Brs) is an inherited disorder associated with risk of ventricular fibrillation and sudden cardiac death in a structurally normal heart. The purpose of this case presentation was to spread awareness about this condition, highlight the importance of timely diagnosis and effective treatment of this channelopathy especially in asymptomatic young athletes at high risk of sudden cardiac death. Methods and results In this report, we discuss the case of a 47-year-old male. He was a tennis player who performed a visit to the sports doctor to have issued a certificate for competitive fitness. He had no familiar history of sudden death or syncope. The patient’s electrocardiogram (ECG) revealed J-point elevation and ST-segment elevation in the right precordial leads V1 and V2 positioned in the second, third, or fourth intercostal space, showing classic type II ‘saddleback’ morphology in V2 and BrS was suspected. Hence, the patient underwent Holter ECG monitoring with evidence of spontaneous type 1 Brugada pattern (‘coved’ morphology), as well as frequent ventricular ectopic beats with left branch block morphology. Indeed, a diagnosis of BrS was made. Antiarrhythmic prophylaxis therapy with hydroquinidine was initiated and the patient was suspended from competitive activity with a 3-month follow-up. Conclusions The BrS is a hereditary disease characterized by a typical ECG pattern potentially predisposing active individuals with no patent structural heart disease to ventricular arrhythmias (VA) and sudden cardiac death (SCD). Nowadays, it is difficult to discern the true burden of BrS due to the unknown real prevalence of asymptomatic patients and the dynamic variability of the ECG pattern in individuals. The purpose of this case presentation was to spread awareness about this condition, highlight the importance of timely diagnosis, and effective treatment of this channelopathy especially in asymptomatic young athletes at high risk of SCD. Indeed, exercise may potentially worsen the ECG abnormalities in BrS patients, resulting in higher peak J-point amplitudes during the vasovagal reaction of the recovery period, possibly leading to an increased risk of cardiac events. Moreover, the enhanced vagal tone in athletes could be both a BrS risk factor and an exercise effect. For this reason, athletic pre-participation screening is essential for minimizing the risk for SCD in athletes participating in either competitive or leisure sporting activities.

B-PO02-201 ELECTRICAL CARDIOVERSION: KEEP AN EYE ON THE T!

Torsades de pointes (TdP) often seen in the setting of QT prolongation is an uncommon arrhythmia after synchronized electrical cardioversion (CV). Report a case of unexpected TdP after successful electrical CV. NA A 78-year-old man with coronary artery disease and prior CABG, ischemic cardiomyopathy with prior LVEF 50-55% was admitted with acute decompensated heart failure with newly depressed LVEF 20-25% and new-onset atrial flutter (AF) with 2:1 AV conduction (Fig. A). Due to persistent rapid ventricular rates despite digoxin and metoprolol, he underwent synchronized CV with successful restoration of sinus rhythm (Fig. B, QTc 478 ms). He experienced an episode of TdP 33 hours after CV, initiated by a short-long-short sequence, preceded by giant T-U waves (Fig. C). He underwent CPR / defibrillation with successful return of spontaneous circulation within 5 minutes. Post-arrest ECG showed sinus rhythm with prolonged QTc (500-620 ms) and macroscopic T-wave alternans (Fig. D); another showed junctional rhythm with giant T-U waves preceding frequent ventricular ectopic beats (Fig. E). Electrolytes were normal. He was treated with isoproterenol; digoxin and metoprolol were discontinued. Coronary angiogram showed no new stenoses. He underwent implantation of secondary prevention dual-chamber ICD with backup pacing rate set at 70 bpm, with no TdP recurrence at 2 months. CV is a common, effective procedure for termination of AF. There is increased risk of TdP due to repolarization abnormalities post CV. Macroscopic T-wave alternans and giant T-U waves are ominous ECG signs of impending ventricular arrhythmias.

Surgical Treatment of Primary Cardiac Tumor Associated with Malignant Arrhythmias.

Pediatric primary cardiac tumor is an extremely rare disease. The tumor can extend into the conduction system and cause malignant arrhythmias. We retrospectively reviewed 6 consecutive cases of children with primary cardiac tumor that manifested as rhythm disturbance. In our center, 6 children were enrolled from October 2009 to August 2016. Detailed operative data and follow-up information were comprehensively collected and statistically analyzed. The patients were ages 1 to 16 years and weighed 7.9 to 44.5 kg. Preoperative ventricular tachycardia was present in 3 patients, frequent ventricular ectopic beats in 1 patient, supraventricular tachycardia in 1 patient, and atrial flutter in 1 patient. All 6 patients underwent a complete tumor resection. The tumors were localized in the left ventricular free wall (3 patients), left ventricular outflow tract (1 patient), left atrium (1 patient), and right atrium (1 patient). One patient received 2 radiofrequency ablation procedures before tumor resection. Postoperative sick sinus syndrome occurred in 1 patient because the tumor infiltrated the sinoatrial node. Tumors from 2 patients were pathologically diagnosed as fibroma and 4 as rhabdomyoma. Reoperation of mitral valve repair was performed in 1 patient 1 year after tumor resection. The mean (± SD) follow-up time was 63.7 ± 31.4 months, and all children were well, with Ross functional classification I and no signs of recurrence or metastasis. In conclusion, cardiac tumor is a rare but nonneglectable reason for arrhythmia, and surgical resection is the optimal procedure, with satisfactory results.

P1502 A clinical case of mitral annulus disjunction syndrome revealed by cardiac MRI

Abstract A 39year old female patient with a family history of probable sudden cardiac death/long QT syndrome (sister died aged 36) was referred to our Arrhythmia/inherited cardiac conditions clinic. Patient was fit and well. She described occasional postural presyncope and some chest pain with stress. Not on any medication that could prolong QT. On examination she appeared well with normal heart sounds and no clinical signs of heart failure. Her ECG in clinic confirmed sinus rhythm with normal QTc at 418msec. There were U waves which may reflect late repolarisation of His Purkinje system. Diagnostic techniques and findings A 24-hour ECG tape to look at the average QT interval, an exercise tolerance test to look for appropriate shortening of QT interval with exercise and an echocardiogram to exclude significant structural abnormality were requested. The 24-hour ECG tape confirmed underlying sinus rhythm with multi-focal aberrant beats <1% of total. One symptom demonstrated short run of ventricular bigeminy. During the exercise tolerance test, QT interval was not obviously prolonged. There were frequent bifocal ventricular ectopic beats in recovery. The echocardiogram showed minor abnormality with mild left ventricular dilatation, otherwise normal findings. Patient referred for cardiac MRI In order to rule out any cardiomyopathy. Cardiac MRI did not show any prolapse on the 3 chamber cine. In addition, the inferior and inferolateral annulus showed thinning passing into the LV, which is a feature of some patients with mitral annulus disjunction syndrome. We went through the echocardiogram and in one single frame images are suspicious of focal P2 prolapse. Learning points: Mitral annulus disjunction (MAD) is an abnormal atrial displacement of the mitral valve leaflet hinge point. It has been associated with mitral valve prolapse and sudden cardiac death. MAD is usually revealed with echocardiogram. In this case report we showed that CMR revealed a MAD previously missed by echo. Abstract P1502 Figure.

P2592Combining home monitoring temporal trends and baseline patient risk profile for predicting impending heart failure hospitalizations. Results from the SELENE HF (BIO.Detect HF IV) study

Abstract Background/Introduction The lack of a validated method to efficiently combine information provided by Remote Monitoring (RM) of implantable defibrillators (ICD) and patient clinical profile has limited the use of RM in the prevention of worsening heart failure episodes. Purpose Our objective was to develop and validate an index combining RM temporal trends and a baseline risk score for predicting the first HF hospitalization after device implantation. Methods We prospectively enrolled 918 patients (81% male, median age 69, interquartile interval [QI], 61/76; Seattle Heart Failure Score [SHFS], 0.17, QI, −0.40/0.75) with indication to ICD (56%), or ICD with cardiac resynchronization therapy (44%). The Home Monitoring (HM) system was activated in all patients after implant to collect several technical and HF-related variables daily. Investigators were blinded to HM reports, and only received automatic alerts for critical technical issues. The primary endpoint was the first adjudicated HF hospitalization. The cohort was a posteriori 1:1 randomized in derivation and validation groups stratified by device type and primary endpoint occurrence. The SHFS was used for baseline risk assessment. Results During a median follow-up of 23 months (QI, 14/36), 62 first HF hospitalizations were adjudicated. In the derivation group, the index was constructed by combining the SHFS and temporal trends of 24-hour and rest mean heart rates, ventricular ectopic beat frequency, arrhythmic atrial burden, heart rate variability, physical exercise, and thoracic impedance. Variable selection was based on an automatic stepwise procedure, after applying appropriate transformations in variable-specific time frames to maximize the area under the receiver operating characteristics curve (AUC). The resulting index was associated to an AUC of 0.88 and an Odds Ratio of 2.72 (confidence interval [CI] 1.97–3.75, p<0.001) for index unitary increase. In the index validation test, first HF hospitalizations were predicted with a sensitivity of 73.3% (CI, 54.1%-87.7%), a median alerting time of 55 days (QI, 20/68), false alert rate of 0.75 (CI, 0.70–0.81) patient-year, and 95.1% false-alert-free days. Conclusion HM temporal trends of selected variables and the SHFS may be combined to timely and efficiently predict the first HF hospitalization after implant, with less than 1 expected per-patient false alert per year. Acknowledgement/Funding BIOTRONIK SE & Co. KG, Berlin, Germany

P4983Safety of dobutamine stress contrast echocardiography; a single-center experience of 15 years

Abstract Introduction Dobutamine stress contrast echo (DSCE) is an accurate method for the diagnosis of coronary artery disease (CAD). Scarcity of serious adverse events has led to its establishment as a popular method for the diagnosis of CAD and to its increased use beyond CAD. However, data regarding the safety of single-line dobutamine and contrast infusion are limited. The aim of our study was to assess the safety of a DSCE protocol using a single line of intravenous access. Methods Over a 15-year period (2004–2018), 34,675 patients underwent DSCE in our department, which was performed using 10–20–30–40–50 μg/kg/h of dobutamine with dosage increase every three minutes, while atropine up to 1mg could also be administered. Two commercially available contrast agents were used at rest and at peak in all patients and a single intravenous line was used for infusion of dobutamine, atropine and contrast agents. Demographic data, risk factors and information concerning the most common cardiovascular or allergic adverse events were available for all patients. Finally, the adverse events of DSCE were compared with respective events reported by relevant studies in order to determine the safety of our method. Results Mean age of patient population was 63.9 (SD: 11.4 years), while 67.9% of patients (n=23,544) were males. There were 22,731 hypertensive patients (65.6%), 9,256 diabetics (26.7%), 21,683 patients (62.5%) had dyslipidemia, 11,760 (33.9%) were smokers and 10,437 (30.1%) had a positive family history of CAD. Adverse events were reported in 876 patients (2.5%). Allergic reaction was reported in 69 patients (0.2%). We recorded 643 patients (1.85%) with non-sustained VT or frequent premature ventricular ectopic beats and 154 patients (0.44%) with AF or SVT episodes leading to protocol termination. In 24 patients (0.07%) with sustained VT, antiarrhythmic drugs were given intravascularly, while in 10 patients (0.03%) with VT or VF, resuscitation was needed. No death was reported. Frequency of life threatening adverse events reported by relevant studies did not differ significantly when compared to the present results. Conclusion DSCE protocols involving single line infusion of dobutamine, atropine and ultrasound enhancing agents are safe, since adverse event rates are low and do not differ significantly to rates reported for unenhanced DSE by other relevant studies. Implementation of such protocols in clinical practice may increase patient comfort and cost-effectiveness and should therefore be encouraged.

Ventricular ectopic beat detection using a wavelet transform and a convolutional neural network

Objective: Ventricular contractions in healthy individuals normally follow the contractions of atria to facilitate more efficient pump action and cardiac output. With a ventricular ectopic beat (VEB), volume within the ventricles are pumped to the body’s vessels before receiving blood from atria, thus causing inefficient blood circulation. VEBs tend to cause perturbations in the instantaneous heart rate time series, making the analysis of heart rate variability inappropriate around such events, or requiring special treatment (such as signal averaging). Moreover, VEB frequency can be indicative of life-threatening problems. However, VEBs can often mimic artifacts both in morphology and timing. Identification of VEBs is therefore an important unsolved problem. The aim of this study is to introduce a method of wavelet transform in combination with deep learning network for the classification of VEBs. Approach: We proposed a method to automatically discriminate VEB beats from other beats and artifacts with the use of wavelet transform of the electrocardiogram (ECG) and a convolutional neural network (CNN). Three types of wavelets (Morlet wavelet, Paul wavelet and Gaussian derivative) were used to transform segments of single-channel (1D) ECG waveforms to two-dimensional (2D) time-frequency ‘images’. The 2D time-frequency images were then passed into a CNN to optimize the convolutional filters and classification. Ten-fold cross validation was used to evaluate the approach on the MIT-BIH arrhythmia database (MIT-BIH). The American Heart Association (AHA) database was then used as an independent dataset to evaluate the trained network. Main results: Ten-fold cross validation results on MIT-BIH showed that the proposed algorithm with Paul wavelet achieved an overall F1 score of 84.94% and accuracy of 97.96% on out of sample validation. Independent test on AHA resulted in an F1 score of 84.96% and accuracy of 97.36%. Significance: The trained network possessed exceptional transferability across databases and generalization to unseen data.

Effect of Trimetazidine Dihydrochloride Therapy on Exercise Capacity in Patients With Nonobstructive Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy causes limiting symptoms in patients, mediated partly through inefficient myocardial energy use. There is conflicting evidence for therapy with inhibitors of myocardial fatty acid metabolism in patients with nonobstructive hypertrophic cardiomyopathy. To determine the effect of oral therapy with trimetazidine, a direct inhibitor of fatty acid β-oxidation, on exercise capacity in patients with symptomatic nonobstructive hypertrophic cardiomyopathy. This randomized, placebo-controlled, double-blind clinical trial at The Heart Hospital, University College London Hospitals, London, United Kingdom was performed between May 31, 2012, and September 8, 2014. The trial included 51 drug-refractory symptomatic (New York Heart Association class ≥2) patients aged 24 to 74 years with a maximum left ventricular outflow tract gradient 50 mm Hg or lower and a peak oxygen consumption during exercise of 80% or less predicted value for age and sex. Statistical analysis was performed from March 1, 2016 through July 4, 2018. Participants were randomly assigned to trimetazidine, 20 mg, 3 times daily (n = 27) or placebo (n = 24) for 3 months. The primary end point was peak oxygen consumption during upright bicycle ergometry. Secondary end points were 6-minute walk distance, quality of life (Minnesota Living with Heart Failure questionnaire), frequency of ventricular ectopic beats, diastolic function, serum N-terminal pro-brain natriuretic peptide level, and troponin T level. Of 49 participants who received trimetazidine (n = 26) or placebo (n = 23) and completed the study, 34 (70%) were male; the mean (SD) age was 50 (13) years. Trimetazidine therapy did not improve exercise capacity, with patients in the trimetazidine group walking 38.4 m (95% CI, 5.13 to 71.70 m) less than patients in the placebo group at 3 months after adjustment for their baseline walking distance measurements. After adjustment for baseline values, peak oxygen consumption was 1.35 mL/kg per minute lower (95% CI, -2.58 to -0.11 mL/kg per minute; P = .03) in the intervention group after 3 months. In symptomatic patients with nonobstructive hypertrophic cardiomyopathy, trimetazidine therapy does not improve exercise capacity. Pharmacologic therapy for this disease remains limited. ClinicalTrials.gov identifier: NCT01696370.

Beat-to-beat detection of aortic valve opening in HeartWare left ventricular assist device patients.

Continuous flow left ventricular assist devices (cfLVADS) result in a significant reduction in aortic valve (AV) opening, which has been associated with several complications. Reliable monitoring of AV opening is needed to determine whether pump speed adjustment may be able to minimize adverse outcomes. We assessed AV status continuously by echocardiography for 4 minutes in 3 states in 18 HeartWare HVAD patients: 2 minutes at rest, and 1 minute each following Valsalva maneuver and supine leg-raising. Using a previously described algorithm, beat-to-beat AV status was compared with the area under the curve of the normalized power spectral density analysis (PSD-AUC) for the corresponding beats of the pump speed waveform. Five thousand five hundred twenty-seven beats were analyzed. AV opening varied between 0% and 100% for the cohort with the median AV opening frequency 21.5%, and median duration of opening of 124msec (range 0-279). The receiver operating characteristic (ROC) curve area for AV opening by the PSD-AUC algorithm was 0.95 (P<0.0001). A PSD-AUC cut-off of 0.82 distinguished between an open and closed AV with 86% sensitivity and 93% specificity. Accuracy was similar in regular cardiac rhythm, atrial fibrillation or with frequent ventricular ectopic beats. Valsalva maneuver and leg-raising had no impact on accuracy. The PSD-AUC was strongly predictive of AV opening duration (P<0.0001). We found that AV status and opening duration can be determined with high accuracy on a beat-to-beat basis irrespective of cardiac rhythm and with low level exercise and changes in filling.

HEART FAILURE AND PREGNANCY: TO DELIVER OR TO CARRY ON

SESSION TITLE: Cardiovascular Disease SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Management of acute decompensated heart failure and life-threatening arrhythmias during pregnancy is challenging. Increasing physiological demands of pregnancy and limited pharmacological treatment options often push physicians to pursue early delivery. We report a rare case of cardiomyopathy manifesting as incessant ventricular tachycardia during second trimester of pregnancy. CASE PRESENTATION: A 30 year-old Caucasian female with no past medical history presented to the hospital with shortness of breath, palpitations, and lower extremity swelling during the 26th week of her first pregnancy. Electrocardiogram and telemetry revealed a high burden of non-sustained polymorphic ventricular tachycardia (VT) (figure 1). Patient was transferred to intensive care unit (ICU) and transthoracic echocardiogram (TTE) showed biventricular failure with left ventricular ejection fraction (LVEF) of 20%, severe left atrial dilation and mitral regurgitation (figure 2). Patient was started on esmolol and lidocaine infusions. A pulmonary artery catheter was placed for hemodynamic monitoring (figure 3). Diuresis was also initiated. Given the persistent VT and evidence of lidocaine toxicity, mexiletine was initiated and lidocaine discontinued. After 7 days, the frequency of ventricular ectopic beats significantly decreased. Considering the likelihood of peripartum cardiomyopathy, bromocriptine was administered, but patient could not tolerate it due to worsening hypotension and nausea. With increasing cardiovascular demands of pregnancy and persistent severe cardiomyopathy, a decision was made to pursue caesarian section at 28 weeks. Given the stress of surgery and mortality associated with it, an Impella CP left ventricular assist device was placed immediately prior to caesarian section. Patient tolerated both procedures well and was subsequently weaned off Impella CP device in the surgical ICU. Baby was also viable. Patient was eventually discharged on metoprolol and mexilitine along with standard therapy as well as a LifeVest. Follow up TTE at 4 months showed slight improvement in LEVF at 25%. Cardiac magnetic resonance imaging revealed extensive patchy and transmural late gadolinium enhancement (figure 3). DISCUSSION: Management of incessant ventricular tachycardia in pregnancy can be difficult as amiodarone is associated with fetal growth retardation. Lidocaine, procainamide and mexiletine are the recommend anti-arrhythmic agents for stable cases. In patients with severely depressed LVEF, caesarean section carries a high mortality rate. Preemptive use of circulatory left ventricular assist device such as Impella CP is potentially life saving. CONCLUSIONS: Cardiomyopathy in pregnancy can present as incessant ventricular tachycardia and should alert physician for further work up. Reference #1: Arany Z, and Elkayam U. Peripartum Cardiomyopathy. Circulation. 2016;133(14):1397-409. DISCLOSURES: No relevant relationships by Anthony Lubinsky, source=Web Response No relevant relationships by Assad Oskuei, source=Web Response

End-Stage Biventricular Failure from Necrotizing Autoimmune Myopathy

Necrotizing autoimmune myopathy is a rare neuromuscular disorder characterized clinically by severe proximal limb muscle weakness and pathologically by necrotic muscle fibers with minimal inflammation. It is often associated with statin therapy, connective tissue diseases, and malignancy. Most have characteristic autoantibodies although a small subset present without myositis-specific autoantibodies. While cardiac involvement is rare, conduction abnormalities, diastolic dysfunction, and wall motion abnormalities have been reported. Severe cardiomyopathy from necrotizing autoimmune myopathy resulting in end-stage biventricular failure is extremely rare without a clear role for guideline-directed medical therapy. A 45-year-old man with hypothyroidism was admitted with several months of worsening proximal muscular weakness. He was found to have new severe biventricular dysfunction with conduction abnormalities during diagnostic work-up. Physical exam was notable for symmetric proximal muscle weakness in upper and lower extremities, sclerodactyly, elevated jugular venous distension, and lower extremity edema. Laboratory testing showed a creatine kinase of 3101 U/L, ANA 1:640, positive RNP antibodies, positive PM/Scl 100 antibodies. Anti-HMGCR antibodies and anti-SRP antibodies were negative. Lower extremity MRI showed diffuse bilateral symmetric myositis around the pelvis consistent with an inflammatory myopathy. EMG suggested irritable myopathy. Left thigh skeletal muscle biopsy showed necrotizing autoimmune myopathy with a paucity of inflammatory cells. Electrocardiogram revealed a right bundle branch block and 1st degree AV block. Frequent atrial and ventricular ectopic beats were seen on telemetry. Transthoracic echocardiogram showed biventricular failure with LVEF 23% and severe global hypokinesis. Cardiac MRI showed patchy foci of delayed subendocardial delayed enhancement. Endomyocardial biopsy did not reveal evidence of lymphocytic infiltration or ongoing myocarditis. Right heart catheterization was notable for elevated biventricular pressures with a cardiac index of 2.18. No obstructive coronary artery disease was seen on coronary angiogram. He was treated with intravenous immunoglobulins, methotrexate, and high-dose prednisone with improvement in proximal weakness. Low-dose spironolactone and lisinopril were started but could not be increased due to degree of hypotension. This case highlights a rare manifestation of an exceedingly rare autoimmune condition associated with high mortality. Given the variability of cardiac involvement in the disorder, a high clinical suspicion is needed to establish an early diagnosis and pursue aggressive treatment with up-front combination immunomodulating therapy, which has been associated with improved outcomes.

Natural history of idiopathic ventricular arrhythmias in children

Idiopathic ventricular arrhythmia in children is usually benign. Ventricular ectopy in children usually is an incidental finding. Prevalence varies with age: neonates nearly 20%, school age 10%, teenagers 20-30%. During natural history total or partial disappearance of idiopathic ventricular ectopy, spontaneously or after treatment was described in about 23% children with premature ventricular beats, 28% with pairs and 65% with ventricular tachycardia. Arrhythmia more often resolves in infants than in older children, more often in arrhythmia with right than left bundle branch block morphology. Idiopathic ventricular tachycardia or frequent ventricular ectopic beats may in small percentage of pediatric patients lead to ventricular dysfunction, but risk factors of this arrhythmic cardiomyopathy in children are not established. Catheter ablation is recommended in children with ventricular dysfunction or hemodynamic compromise presumed to be due to ventricular arrhythmia, as primary therapy or in patients with arrhythmia not controlled medically

Case 3: Respiratory Distress and Tachycardia in a Preterm Neonate

A 31-week-gestation male infant is delivered vaginally in the setting of preterm labor and chorioamnionitis. The pregnancy was remarkable for late prenatal care, but no other complications. Maternal antenatal testing results were normal and the mother denied any significant medical history. The infant is initially stunned, but quickly recovers, with Apgar scores of 1 and 7 at 1 and 5 minutes, respectively. His size is appropriate for gestational age and his vital signs in the intensive care nursery include a temperature of 98.8°F (36.5°C), pulse of 172 beats/min, right lower extremity blood pressure of 76/34 mm Hg, respiratory rate of 62 breaths/min, and oxygen saturation of 98% on nasal continuous positive airway pressure support at 5 cm H2O and 21% fraction of inspired oxygen. On examination, the infant’s anterior fontanelle is soft, flat, and approximately 1 fingertip in size. His lungs are clear despite a mildly increased respiratory effort, including grunting and subcostal retractions. He has normal first and second heart sounds, a gallop rhythm, and no murmurs, and his liver is palpable 4 cm below the right costal margin. On investigation, chest radiography demonstrates an enlarged cardiac silhouette (Fig 1), and echocardiography shows findings consistent with restrictive cardiomyopathy, normal systolic function, but impaired diastolic function (Fig 2). Given this rare finding, pediatric cardiology is consulted, which recommends conducting a comprehensive cardiomyopathy genetic testing panel. During his first week after delivery, the infant develops frequent ventricular ectopic beats …

Prognostic Role of Ventricular Ectopic Beats in Systemic Sclerosis: A Prospective Cohort Study Shows ECG Indexes Predicting the Worse Outcome.

BackgroundArrhythmias are frequent in Systemic Sclerosis (SSc) and portend a bad prognosis, accounting alone for 6% of total deaths. Many of these patients die suddenly, thus prevention and intensified risk-stratification represent unmet medical needs. The major goal of this study was the definition of ECG indexes of poor prognosis.MethodsWe performed a prospective cohort study to define the role of 24h-ECG-Holter as an additional risk-stratification technique in the identification of SSc-patients at high risk of life-threatening arrhythmias and sudden cardiac death (SCD). One-hundred SSc-patients with symptoms and/or signs suggestive of cardiac involvement underwent 24h-ECG-Holter. The primary end-point was a composite of SCD or need for implantable cardioverter defibrillator (ICD).ResultsFifty-six patients (56%) had 24h-ECG-Holter abnormalities and 24(24%) presented frequent ventricular ectopic beats (VEBs). The number of VEBs correlated with high-sensitive cardiac troponin T (hs-cTnT) levels and inversely correlated with left-ventricular ejection fraction (LV-EF) on echocardiography. During a mean follow-up of 23.1±16.0 months, 5 patients died suddenly and two required ICD-implantation. The 7 patients who met the composite end-point had a higher number of VEBs, higher levels of hs-cTnT and NT-proBNP and lower LV-EF (p = 0.001 for all correlations). All these 7 patients had frequent VEBs, while LV-EF was not reduced in all and its range was wide. At ROC curve, VEBs>1190/24h showed 100% of sensitivity and 83% of specificity to predict the primary end-point (AUROC = 0.92,p<0.0001). Patients with VEBS>1190/24h had lower LV-EF and higher hs-cTnT levels and, at multivariate analysis, the presence of increased hs-cTnT and of right bundle branch block on ECG emerged as independent predictors of VEBs>1190/24h. None of demographic or disease-related characteristics emerged as predictors of poor outcome.ConclusionsVEBS>1190/24h identify patients at high risk of life-threatening arrhythmic complications. Thus, 24h-ECG-Holter should be considered a useful additional risk-stratification test to select SSc-patients at high-risk of SCD, in whom an ICD-implantation could represent a potential life-saving intervention.

Assessment of energy expenditure, physical activity and sleep pattern in patients with frequent symptomatic ventricular ectopic beats

Abstract Background Ventricular ectopic beats (VEBs) are considered as benign ventricular arrhythmias in patients without structural heart disease. However, symptomatic frequent VEBs can adversely affect energy metabolism. The present study aimed to determine the effect of symptomatic frequent VEBs on energy expenditure, physical activity and sleep pattern. Methods Thirty-seven patients with symptomatic frequent VEBs and no structural heart diseases were enrolled. Patients underwent simultaneous 24-hour-ambulatory Holter electrocardiogram monitoring and the BodyMedia armband device monitoring which measures energy expenditure. Data acquired from both devices were compared with the data acquired from healthy volunteers in the control group. Results Total energy expenditure (TEE) was higher in the patient group than the control group (1470 ± 353 kcal vs 1125 ± 275 kcal, P P = 0.028), physical activity duration (PAD) (0.35 vs. 0.48, P = 0.007) and sleep duration (SDN) (3.15 vs. 4.31, P = 0.004) were significantly lower in the patient group than control group. VEBs frequency was inversely correlated with only SDN ( r = −0.374, P = 0.027). Conclusion Total energy expenditure (TEE) is increased in patients with symptomatic frequent VEBs in comparison with healthy subjects while PAD, average metabolic equivalence (aMETs) and SDN are decreased. VEBs frequency was inversely correlated with SDN.

Spontaneous ventricular tachyarrhythmias in β2-adrenoceptor transgenic mice in relation to cardiac interstitial fibrosis.

Myocardial fibrosis is regarded as a pivotal proarrhythmic substrate, but there have been no comprehensive studies showing a correlation between the severity of fibrosis and ventricular tachyarrhythmias (VTAs). Our purpose was to document this relationship in a transgenic (TG) strain of mice with fibrotic cardiomyopathy. TG mice with cardiac overexpression of β2-adrenoceptors (β2-AR mice) and non-TG (NTG) littermates were studied at 4-12 mo of age. VTA was quantified by ECG telemetry. The effect of pharmacological blockade of β2-ARs on VTA was examined. Myocardial collagen content was determined by hydroxyproline assay. NTG and TG mice displayed circadian variation in heart rate, which was higher in TG mice than in NTG mice (P <0.05). Frequent spontaneous ventricular ectopic beats (VEBs) and ventricular tachycardia (VT) were prominent in TG mice but not present in NTG mice. The frequency of VEB and VT episodes in TG mice increased with age (P < 0.01). Ventricular collagen content was greater in TG mice than in NTG mice (P <0.001) and correlated with age (r = 0.71, P < 0.01). The number of VEBs or VT episodes correlated with age (r = 0.83 and r = 0.73) and the content of total or cross-linked collagen (r = 0.62∼0.66, all P <0.01). While having no effect in younger β2-TG mice, β2-AR blockade reduced the frequency of VTA in old β2-TG mice with more severe fibrosis. In conclusion, β2-TG mice exhibit interstitial fibrosis and spontaneous onset of VTA, becoming more severe with aging. The extent of cardiac fibrosis is a major determinant for both the frequency of VTA and proarrhythmic action of β2-AR activation.

Cardiac Repolarization and Autonomic Regulation during Short-Term Cold Exposure in Hypertensive Men: An Experimental Study

ObjectivesThe aim of our study was to assess the effect of short-term cold exposure, typical in subarctic climate, on cardiac electrical function among untreated middle-aged hypertensive men.MethodsWe conducted a population-based recruitment of 51 hypertensive men and a control group of 32 men without hypertension (age 55–65 years) who underwent whole-body cold exposure (15 min exposure to temperature −10°C, wind 3 m/s, winter clothes). Conduction times and amplitudes, vectorcardiography, arrhythmias, and heart rate variability (autonomic nervous function) were assessed.ResultsShort-term cold exposure increased T-peak to T-end interval from 67 to 72 ms (p<0.001) and 71 to 75 ms (p<0.001) and T-wave amplitude from 0.12 to 0.14 mV (p<0.001) and from 0.17 to 0.21 mV (p<0.001), while QTc interval was shortened from 408 to 398 ms (p<0.001) and from 410 to 401 ms (p<0.001) among hypertensive men and controls, respectively. Cold exposure increased both low (from 390 to 630 ms2 (p<0.001) and 380 to 700 ms2 (p<0.001), respectively) and high frequency heart rate variability (from 90 to 190 ms2 (p<0.001) and 150 to 300 ms2 (p<0.001), respectively), while low-to-high frequency-ratio was reduced. In addition, the frequency of ventricular ectopic beats increased slightly during cold exposure. The cold induced changes were similar between untreated hypertensive men and controls.ConclusionsShort-term cold exposure with moderate facial and mild whole body cooling resulted in prolongation of T-peak to T-end interval and higher T-wave amplitude while QTc interval was shortened. These changes of ventricular repolarization may have resulted from altered cardiac autonomic regulation and were unaffected by untreated hypertension.Trial RegistrationClinicalTrials.gov NCT02007031