A rare case of recurrent paroxysmal supraventricular tachycardia in pregnancy managed with adenosine, a wonder drug

Paroxysmal supraventricular tachycardia (PSVT) is the most common sustained arrhythmia during pregnancy and a challenging situation due to lack of evidence based guidelines. About 50% of PSVT, who fail to respond to vagal maneuvres, responds to therapies as pharmacologic agents as adenosine and electrocardioversion. We reported a case of 29 years old primigravida women with no organic heart disease who presented at 21 weeks of period of gestation with complaints of palpitations and shortness of breath. Her ECG revealed PSVT for which she received adenosine as anti-arrhythmic for conversion to sinus rhythm. She was started prophylactically on tablet metoprolol 25 mg twice daily, as advised by cardiologist. In third trimester, she had recurrent episodes of PSVT for which she received adenosine in emergency department. She delivered a healthy female baby by an elective caesarean section done under spinal anesthesia. Fortunately, her intraoperative and postpartum was uneventful with no recurrence of PSVT during hospital stay. She was discharged on day 4 of caesarean section on tablet metoprolol 12.5 mg twice daily and followed in postpartum period for complications. To summarize, PSVT occurring during pregnancy, labour or at caesarean section is not uncommon. Treatment remains a challenge though, as clinical decision must be tackled with appropriate consideration of both maternal and fetal factors. So, multi-disciplinary approach is needed for treatment including obstetrician, cardiologists, physician and neonatologists. Our case highlighted the necessity of keeping anti-arrhythmic drugs such as adenosine readily available on the labour ward.

Advances in the Molecular Genetics of Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia is a primary arrhythmogenic syndrome with genetic features most commonly seen in adolescents, with syncope and sudden death following exercise or agitation as the main clinical manifestations. The mechanism of its occurrence is related to the aberrant release of Ca2+ from cardiomyocytes caused by abnormal RyR2 channels or CASQ2 proteins under conditions of sympathetic excitation, thus inducing a delayed posterior exertional pole, manifested by sympathetic excitation inducing adrenaline secretion, resulting in bidirectional or polymorphic ventricular tachycardia. The mortality rate of the disease is high, but patients usually do not have organic heart disease, the clinical manifestations may not be obvious, and no significant abnormal changes in the QT interval are often observed on electrocardiography. Therefore, the disease is often easily missed and misdiagnosed. A number of genetic mutations have been linked to the development of this disease, and the mechanisms are different. In this paper, we would like to summarize the possible genes related to catecholaminergic polymorphic ventricular tachycardia in order to review the genetic tests currently performed, and to further promote the development of genetic testing techniques and deepen the research on the molecular level of this disease.

Sudden Cardiac Death in the General Population: Can We Improve Risk Stratification and Prevention?

A total of 15 to 20% of deaths worldwide are sudden (within 1 hour of symptom onset). Our ability to predict and prevent sudden cardiac death (SCD) in the general population, in which 85% have no known organic heart disease (OHD) or stable OHD with left ventricular ejection fraction >40%, is limited to poor. The purpose of this commentary is to suggest a new approach to SCD in this population. Oxidative stress is a common thread in development and progression of the major cardiac diseases associated with SCD. It has a profound adverse effect upon heart rate variability (HRV), sympathetic tone (S), and parasympathetic tone (P). Recently, developed technology finally has allowed accurate measures of S and P. Using this technique, the general population can be screened, those at risk for SCD can be identified with a higher degree of success, and preventative measures instituted. For example, in 133 geriatric type 2 diabetics with S and/or P abnormalities upon screening, the potent and natural antioxidant (r)α lipoic acid reduced SCD (relative risk reduction) 43% (p = 0.0076), mean follow-up 6.31 years. Diabetes mellitus patients have high glycemic oxidative stress. Addressing oxidative stress S and P abnormalities can reduce SCD. S and P screening of the general population will be discussed.

Electrocardiographic abnormalities in severe anaemia and its reversibility after correction of anaemia

Background: Anaemia is one of the commonest clinical problems in our country. It affects various organs including the heart. Clinical manifestations of anaemia referable to cardiovascular system may closely simulate symptoms and signs of organic heart disease. It includes some electrocardiogram (ECG) changes also. ECG changes in anaemia show correlation to haemoglobin (Hb) concentration and the changes are reversible after correction of anaemia. In this study, the main objective was to study electrocardiographic changes in patients with severe anaemia and ECG reversibility after treatment of anaemia.Methods: 50 patients admitted in medicine wards of Shri B. M. Patil Medical College, Hospital and Research Center, Vijayapura for severe anaemia (Hb concentration less than or equal to 7 gm %) were studied for ECG changes. All patients were reassessed for reversibility of changes after treatment.Results: Out of 50 patients with severe anaemia, 20 patients were having Hb % of 3 to 5 gm %. Of which 16 patients were having ECG changes (10 were females and 6 were males). All ECG changes were reverted to normal after correction of anaemia, except one patient (showed pre-treatment T wave inversion and post-treatment flat T waves).Conclusions: ECG abnormalities in patients with severe anaemia are more common in females. ECG abnormalities in patients with severe anaemia (Hb 5 gm %) can get reverted to normal after correction of anaemia.

Identification of potential core genes in atrial fibrillation based on bioinformatics analysis

OBJECTIVE:Atrial fibrillation (AF) is one of the most common arrhythmias, which is caused by a number of minorring disorders caused by the heart owner's guide. It is noted in almost all organic heart disease and can also occur in non-organic heart disease,causing serious complications, such as heart failure and arterial embolism, seriously threaten people's health.Atrial fibrillation can cause serious complications, such as heart failure and arterial embolism, which seriously threaten people's health. Clinically, according to the characteristics of atrial fibrillation, atrial fibrillation is divided into paroxysmal atrial fibrillation,persistent atrial fibrillation, permanent atrial fibrillation (cannot be converted to sinus rhythm).Among them, persistent atrial fibrillation poses the greatest threat to people's health.So the main purpose of this study is to identify the differential genes in patients with permanent atrial fibrillation. MATERIALS AND METHODS:To explore potential differential genes for permanent atrial fibrillation, we analyzed three microarray datasets GSE2240 derived from the Gene Expression Omnibus (GEO) database. We used the“limma”function package of R software to screen differentially expressed genes(DEGs), and used the“pheatmap”function package to construct heatmaps for the screened differential genes.Visualization and Integration Discovery (DAVID) ,Cytoscape ,BMKcloud and String platforms were utilized for Genome Ontology (GO) analysis,Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis , PPI(protein-proteinInteraction) network analysis ,module analysis,and identification hub genes based on the selected differential genes.RESULTS:74 DEGs in total were identified, including 41 up- and 33 downregulated genes. These DEGs were mainly enriched in PI3K-Akt signaling pathway ,cGMP-PKG signaling pathway, Focal adhesion, and so on. The module analysis filtered out 12 key genes, including PRL, CREB1, AGO2, NAMPT, IGFBP2, FGF7, ANGPT2, SYT13, NRXN1, AQP4, TCEAL2, and CPLX1. 2 Hub genes were identified, including IGFBP2, and FGF7.CONCLUSIONS:IGFBP2 and FGF7 were identified as Hub genes of AF, which helped us to understand more deeply the pathophysiological mechanism of AF.

P1547 Left ventricular papillary muscle strain as an indicator of hypertrophic cardiomyopathy

Background Although recognized as part of the mitral valve complex, few studies have assessed the left ventricular papillary muscle. We confirmed during autopsy that papillary muscle consists of longitudinal aligned muscle fibers, and that the papillary muscle originated from the left ventricular oblique muscle. Therefore, papillary muscle contraction was considered only in the longitudinal direction. Purpose We previously reported that left ventricular papillary muscle strain (LV-PMS) in 100 patients without organic heart disease was correlated with multiple left ventricular function assessment parameters. This study aimed to determine whether left ventricular papillary muscle strain (LV-PMS) in patients with hypertrophic cardiomyopathy (HCM) is correlated with left ventricular function parameters as in non-HCM patients. Methods We measured left ventricular papillary muscle strain (LV-PMS) between two points on papillary muscles except where chordae adhere and the left ventricular wall, and compared values between patients without organic heart disease and with hypertrophic cardiomyopathy (HCM). Among 1,344 patients who were assessed by echocardiography at our hospital between January and June 2018, we selected 42 (mean age, 68.9 ± 17.4 years; male, 67%) who did not have coronary heart disease and in whom left ventricular papillary muscle contraction strain (LV-PMS) could be determined. Obvious anterior and posterior papillary muscles were evaluated. We also analyzed age, EF, e’, s’, E/e’, E/A, left atrial volume index (LAV-I) and global longitudinal strain (GLS) as possibly relevant factors. Results Among the 42 patients, 22 (52%) and 17 (40%) had hypertension and HCM, respectively. We measured the strength of linear associations among paired variables (LV-PMS, age, EF, e’, s’, E/e’, E/A, LAV-I and GLS) using Pearson product-moment correlation coefficients. Age (r = 0.64), e’ (r = -0.76), s’ (r = -0.61), LAV-I (r = 0.61) and GLS (r = 0.57; all p < 0.001), as well as E/e’ (r = 0.44, p < 0.05) significantly correlated in patients without HCM, whereas only GLS correlated in patients with HCM (r = 0.723, p < 0.001). One-way analyses of variance showed that LV-PMS values significantly differed only among patients without HCM when categorized according to age < 50, ≥ 50 < 75 and > 75 years (p < 0.001), whereas these values significantly differed in all patients (p < 0.05) when categorized according to GLS < -20%, ≥ -20 to < -15% and > -15%. Conclusions We found that LV-PMS correlated with five factors including age in patients without HCM, but only with GLS in those with HCM. Despite the small study cohort, we considered that LV-PMS and GLS would be useful for evaluating left ventricular function in patients with HCM.

P275 Feasibility and accuracy of the automated quantification of two- and three-dimensional left ventricular ejection fraction and its role in the arrhythmic risk stratification of organic heart disease

BACKGROUND New automated approaches for left heart chamber quantification based on adaptive analytics algorithms have been introduced for both two- (2DE) and three-dimensional (3DE) echocardiography. These algorithms measure a left ventricular ejection fraction (LVEF) and reduce the intra- and inter-observer variability associated with the conventional manual tracing of LV endocardial borders. However, the clinical utility of these algorithms in the sudden cardiac death (SCD) risk stratification of patients with organic heart disease remains to be clarified. PURPOSE We sought to test the feasibility and the accuracy of two automated algorithms that measure 2DE and 3DE LVEF in patients with impaired LV systolic function and to define the cut-off values for fully automated 2DE and 3DE LVEF that could predict major arrhythmic events (MAE). We wanted also to assess the feasibility of replacing manual 2DE and semi-automated (SA) 3DE LVEF with fully-automated (FA) 2DE and 3DE LVEF respectively, in the stratification of high arrhythmic risk patients. METHODS We prospectively enrolled 240 patients (63 ± 13 years, 81% men) with both ischemic and non-ischemic cardiomyopathy with 2DE LVEF < 50%, no previous MAE or coronary artery revascularization < 90 days, after at least 3 months of optimal medical therapy for heart failure. MAE were defined as SCD, resuscitated cardiac arrest (CA), ventricular fibrillation, sustained ventricular tachycardia and appropriate ICD shocks. The risk detection cut-off values for 2DE and 3DE FA LVEF were computed using the maximally selected rank statistics method. In order to predict the risk of MAE we created four different risk models, including both clinical characteristics (age, NYHA class, aetiology of the LV dysfunction) and imaging-derived data (2DE manual LVEF, 2DE FA LVEF, 3DE SA LVEF and 3DE FA LVEF), analyzed by a ROC curve. RESULTS During a 27 ± 25months follow-up period, 31 patients (13%) presented MAE including SCD (n= 22; 9%), resuscitated CA (n = 3; 1%) and appropriate ICD shocks (n = 6; 2%). Both 2DE and 3DE FA LVEF showed high feasibility (92% and 95%, respectively), and good agreement with conventional LVEF (2DE mean difference 4 ± 7%, and 3DE mean difference 4 ± 7%). We identified two FA LVEF cut-offs for the MAE detection: 2DE <39% (p = 0.006) and 3DE <37% (p = 0.005). The model including the 2DE FA LVEF showed an area under the curve (AUC) larger than the one including conventional 2DE LVEF (0.83 vs 0.80). Conversely, the AUC obtained with FA 3DE LVEF model was slightly lower than the one obtained using SA 3DE LVEF model (0.80 vs 0.84). CONCLUSIONS Both 2DE and 3DE FA LVEF are feasible and accurate alternative to the conventional (manual) or SA endocardial border tracing. The use of specific FA 2DE LVEF cut-off values showed a comparable predictive power in the MAE risk stratification compared to the conventional one with the advantage of very low intra- and inter-observer variability.

P1581 The global myocardial work index is a powerful predictor of major arrhythmic events in patients with organic heart disease and reduced left ventricular ejection fraction

Background Current guidelines recommend implantable cardioverter defibrillator (ICD) for primary prevention of sudden cardiac death in patients with left ventricular ejection fraction (2DE LVEF) by two-dimensional echocardiography≤ 35%. However, new echocardiography parameters of LV function such as the mechanical dispersion (MD), the LVEF by three-dimensional echocardiography (3DE) and the global myocardial work index (GWI) have been reported to provide a more accurate stratification of the arrhythmic risk, and potentially improve ICD patient selection. Purpose We wanted to compare the arrhythmic risk predictive power of the new parameters of LV function with the conventional 2DLVEF. Material and Methods we prospectively enrolled 216 patients (63 ± 12 years, 88% men) with organic heart diseases and 2DE LVEF <50%, in whom we re-measured LVEF using 3DE, and obtained MD and GWI using 2DE speckle tracking. Major arrhythmic events were defined as sudden cardiac death, sustained ventricular tachycardia, ventricular fibrillation and appropriate ICD shocks. We assessed the predictive power of 4 different parameters: 2DE LVEF< 35%; 3DE LVEF< 35%; MD > 80 ms; and GWI< 672 mmHg% to identify patients at risk of major arrhythmic events. Results During a mean follow-up of 27 ± 24 months, 24 patients (10%) experienced sudden cardiac death, whereas 28 patients (13%) presented major arrhythmic events. The predictive power in terms of major arrhythmic events prediction (Harrel C statistics) improved from 0.67 (95%CI 0.57-0.76) for 2DE LVEF< 35%, to 0.73 (95%CI 0.64-0.82) for 3DE LVEF< 35%, and 0.77 (95%CI 0.68-0.86) for GWI < 672 mm Hg%. Whereas, MD > 80 ms showed a limited predictive power (HCS= 0.53, 95%CI 0.41-0.76)). Conclusions GWI< 672 mm Hg% was the most accurate predictor of major arrhythmic events among echocardiography parameters in patients with organic heart disease and LVEF < 50%.

P6005Incidence and clinical characteristics of coronary artery spasm in patients with out-of-hospital cardiac arrest

Background Substantial cases of out-of-hospital cardiac arrest (OHCA) due to acute coronary syndrome have been recognized thus far, but there have been few reports about the aetiology of patients with OHCA without the organic heart disease. Especially, coronary artery spasm would be one of the causes of OHCA. Purpose This study aimed to investigate causes of OHCA without the organic heart disease and to investigate the characteristics and angiographic findings of OHCA patients with vasospastic angina (VSA). Methods Between January 2010 and April 2018, 920 patients with OHCA caused by probable or definite cardiovascular disease were transferred to our hospital. Return of spontaneous contraction was successfully achieved in 151 patients, among whom diagnosis was made in 130 patients. First, we analysed the causes of OHCA in these patients. Second, we compared clinical and angiographic characteristics between the VSA group with OHCA (OHCA-VSA) and the VSA group without OHCA (stable VSA; n=72) from our database. Results Among the 130 patients, 95 (73%) had the organic heart disease; 72, acute coronary syndrome; 19, myocardial disease; 2, valvular heart disease; and 1, congenital heart disease. There were 35 patients (27%) without the organic heart disease. Nineteen patients had primary (i.e., Brugada syndrome, QT prolongation) or secondary arrhythmia (i.e. drug adverse effect). Electrocardiogram, coronary angiogram, and LV structure and function were normal in 35 patients. However, there were 16 patients (11%) with VSA defined by Japanese guideline. The OHCA-VSA group was significantly younger (50±14) than the stable VSA group (64±11, P=0.003). The incidence of diffuse-type spasm in the OHCA-VSA group (100%) was significantly higher than that in the stable VSA group (100% vs. 69%, P<0.05). In addition, the incidence of triple-vessel coronary spasm in the OHCA-VSA group was significantly higher than that in the stable VSA group (86% vs. 25%, P=0.003). Conclusion OHCA patients without the organic heart disease had considerable cases of VSA, in addition to primary or secondary arrhythmia. Furthermore, the severity of spasm in the OHCA-VSA group was more serious and extensive than in comparison with the stable VSA group.