Clinical significance of unexplained persistent sinus tachycardia in women with structurally normal heart during the peripartum period.

BACKGROUND: Persistent sinus tachycardia (ST) is frequently encountered during pregnancy and peripartum period and its etiology often remains elusive. We sought to examine the possible association between unexplained persistent ST and obstetric outcomes. METHODS: A case control study was conducted using chart review of women admitted in labor to one of 7 hospitals of Northwell Health between January 2015 to June 2021. After excluding women with structurally abnormal hearts, we identified patients with persistent ST during the peripartum period, defined as a heart rate of more than 100 bpm for more than 48 h. A control group was created by randomly subsampling those who did not meet the inclusion criteria for sinus tachycardia. Obstetric outcomes were measured as mother's length of stay (LOS), pre-term labor (PTL), admission to the neonatal ICU (NICU), and whether she received cesarean-section (CS). RESULTS: Seventy-eight patients with persistent ST were identified, out of 141,769 women admitted for labor throughout the Northwell Health system. 23 patients with ST attributable to infection or hypovolemia from anemia requiring transfusion and 55 with unclear etiology were identified. After adjusting for age and parity, pregnant mothers with ST were 2.35 times more likely to have a CS than those without (95% CI: 1.46-3.81, p = 0.0005) and had 1.38 times the LOS (1.21- 1.56, p < 0.0001). Among mothers with ST, those with unexplained ST were 2.14 times more likely to have a CS (1.22-3.75, p = 0.008). CONCLUSION: Among pregnant patients, patients with ST have higher rates of CS.This association is unclear, however potential mechanisms include catecholamine surge, indolent infection, hormonal fluctuations, and medications. More studies are needed to explore the mechanism of ST in pregnant woman to determine the clinical significance and appropriate management.

Tachycardia in hyperthyroidism: Not so common.

OBJECTIVE: The commonly held association of hyperthyroidism with sinus tachycardia and widened pulse pressure (PP) has not been reassessed in decades despite patients with hyperthyroidism in current practice not always present with these signs. The study objective was to assess prevalence and variability of sinus tachycardia and widened PP in present day among individuals with different degrees of hyperthyroidism. METHODS: Data was collected retrospectively from 248 adult patients in an outpatient setting with biochemical evidence of hyperthyroidism, recorded heart rate (HR) and blood pressure (BP) who were not treated with medications that can influence these parameters. RESULTS: Mean age was 42.0 ± 14.2 years with 66.9% being female. Median free thyroxine (fT4) level was 3.49 (IQR 2.42-4.58) ng/dL and thyroid stimulating hormone (TSH) 0.02 (IQR 0.01-0.03) mIU/L. Tachycardia, defined as HR >100 bpm, was present in 28.2%. In the lowest and highest fT4 quartiles, tachycardia was present in 16.4% and 38.7% respectively. Using logistic regression, tachycardia was associated with higher fT4 and diastolic BP. More lenient outcome of tachycardia with HR >90 bpm was seen in 47.2%. Widened PP, defined as >50 mmHg, was observed in 64.1% of patients and correlated with higher fT4 and BP. CONCLUSIONS: Tachycardia is not a common feature of hyperthyroidism today. The relatively infrequent finding of tachycardia in this study compared to older studies may reflect differences in the way medicine is practiced today. The increased ordering of thyroid function tests most likely unmasked cases of mild or asymptomatic thyrotoxicosis. A widened PP was a more prevalent clinical finding in this study.

Prevalence of inappropriate sinus tachycardia and the comparison of the heart rate variability characteristics with propensity score-matched controls.

OBJECTIVE: Inappropriate sinus tachycardia (IST) is a syndrome characterized by an elevated resting heart rate with distressing symptoms and no secondary cause of sinus tachycardia. This study was conducted to evaluate both the prevalence of IST among symptomatic patients and heart rate variability (HRV) characteristics. METHODS: The records of all consecutive symptomatic patients who had undergone 24-hour Holter monitoring between September 2015 and November 2016 at a single center were retrospectively evaluated. IST was defined as a 24-hour mean heart rate (HR) of ≥90 beats/minute and a resting HR of ≥100 beats/minute in the absence of any secondary cause of sinus tachycardia. All of the study data related to clinical characteristics, symptoms, concomitant diseases, and Holter electrocardiogram parameters were obtained from the electronic hospital records. A propensity age- and sex-matched control group was selected from a non-IST patient cohort. RESULTS: A total of 1865 consecutive patients were evaluated and 32% were excluded due to an inadequate Holter recording period or insufficient quality, atrial fibrillation episodes, atrioventricular block, or >1% atrial or ventricular extrasystoles. Among 1265 patients with sinus rhythm, 4.98% (n=63) had IST. The IST patients were younger (39.6±17.4 vs. 50.2±17.2 years; <0.001), and female gender was more prominent (60.3% vs. 43.8%; p=0.009). All of the time and frequency domain parameters of HRV except the low frequency/high frequency ratio were significantly reduced in the IST group compared with the propensity-matched controls. CONCLUSION: The IST prevalence among symptomatic patients in sinus rhythm was 4.98%. IST was primarily seen in younger women, and they had diminished time and frequency domain HRV parameters.

Natural history and clinical outcomes of inappropriate sinus tachycardia.

BACKGROUND: Limited data are available regarding the demographics, disease associations, and long-term prognosis of patients with inappropriate sinus tachycardia (IST). OBJECTIVE: To establish epidemiologic data for patients with IST, including symptom onset, comorbid disease, and long-term outcomes. METHODS: We retrospectively reviewed all patients with an IST diagnosis at the Mayo Clinic (Rochester, MN) during a 20-year period (1998-2018). We extracted demographic data and clinical outcomes compared to an age and gender-matched control group with atrioventricular nodal reentry tachycardia (AVNRT). RESULTS: Within the study period, a total of 305 patients with IST were identified (mean follow-up 3.5 years) with 92.1% female and mean age 33.2 ± 11.2 years. The most frequently identified circumstances triggering the condition included pregnancy (7.9%) and infectious illness (5.9%) while the most common comorbid conditions were depression (25.6%) and anxiety (24.6%). At diagnosis, the mean left ventricular ejection fraction (LVEF) was 62.3 ± 6.2%, with 77 patients having follow-up echocardiographic data. No significant difference in LVEF was seen after a mean 4.9 ± 4.3-year follow-up (baseline LVEF 59.8 ± 10.7% vs subsequent 61.4 ± 8.1%; P = .2971). Two deaths occurred within the study period, with one related to myocardial infarction and the other noncardiac; compared to an age and gender-matched AVNRT control group there was no excess mortality during the follow-up period. CONCLUSIONS: In our study cohort, IST predominately affects young females with structurally normal hearts and modest coexistent psychiatric disease. In most cases of IST, a major event occurring just before or at the time of diagnosis could not be identified, although nearly 8% of patients first noted symptoms during or shortly after pregnancy. In our cohort, there was no evidence of cardiomyopathy or mortality related to IST.

ECG changes in patients with primary hyperthyroidism.

INTRODUCTION: Thyroid hormones plays key role in regulating cardiovascular system. Its imbalance leads to various electrophysiological changes in cardiovascular system. This study was done to determine the frequency of electrocardiographic (ECG) changes in patients with primary hyperthyroidism. METHODS: It was a descriptive cross-sectional study conducted in the Department of Medicine, Medical Unit III, Ward-7, Jinnah Postgraduate Medical Centre, Karachi, from October 2013 to April 2014. A total of 103 patients newly diagnosed with primary hyperthyroidism were included in this study. Venous blood samples were collected for T3, T3, TSH analyzed by radioimmunoassay. ECG was performed. Outcome variables were the ECG changes i.e. sinus tachycardia and atrial fibrillation. RESULTS: The average age of the patients was 30.09±5.57 years (95%CI: 29 to 31.18). Out of 103 cases, 19 (18.45%) were male and 84 (81.55%) were female. Sinus tachycardia was observed in 60.19% (62/103) patients whereas atrial fibrillation was found in 11.65 (12/103) of cases. CONCLUSION: In this study frequency of electrocardiographic changes in term of sinus tachycardia was high. This report has emphasized the importance of thyrotoxicosis as a cause of cardiac morbidity and mortality in patients with thyrotoxicosis. These cardiac complications are readily reversible if timely optimal treatment is offered.

Alcohol consumption, sinus tachycardia, and cardiac arrhythmias at the Munich Octoberfest: results from the Munich Beer Related Electrocardiogram Workup Study (MunichBREW).

AIMS: Alcohol is a risk factor for cardiac arrhythmias. Retrospective analyses suggest supraventricular arrhythmias consecutive to acute alcohol consumption, but prospective data are limited. We intended to prospectively associate acute alcohol consumption with cardiac arrhythmias. METHODS AND RESULTS: At the 2015 Munich Octoberfest, we enrolled 3028 voluntary participants who received a smartphone-based ECG and breath alcohol concentration (BAC) measurements. ECGs were analysed for cardiac arrhythmias (sinus tachycardia, sinus arrhythmia, premature atrial/ventricular complexes, atrial fibrillation/flutter) and respiratory sinus arrhythmia. By multivariable adjusted logistic regression we associated BACs with cardiac arrhythmias. Similarly, we analysed 4131 participants of the community-based KORA S4 Study (Co-operative Health Research in the Region of Augsburg) and associated cardiac arrhythmias with chronic alcohol consumption. In our acute alcohol cohort (mean age 34.4 ± 13.3 years, 29% women), mean BAC was 0.85 ± 0.54 g/kg. Cardiac arrhythmias occurred in 30.5% (sinus tachycardia 25.9%; other arrhythmia subtypes 5.4%). Breath alcohol concentration was significantly associated with cardiac arrhythmias overall (odds ratio (OR) per 1-unit change 1.75, 95% confidence interval (CI) 1.50-2.05; P < 0.001) and sinus tachycardia in particular (OR 1.96, 95%CI 1.66-2.31; P < 0.001). Respiratory sinus arrhythmia measuring autonomic tone was significantly reduced under the influence of alcohol. In KORA S4, chronic alcohol consumption was associated with sinus tachycardia (OR 1.03, 95%CI 1.01-1.06; P = 0.006). CONCLUSIONS: Acute alcohol consumption is associated with cardiac arrhythmias and sinus tachycardia in particular. This partly reflects autonomic imbalance as assessed by significantly reduced respiratory sinus arrhythmia. Such imbalance might lead to sympathetically triggered atrial fibrillation resembling the holiday heart syndrome. CLINICALTRIALS.ORG ACCESSION NUMBER: NCT02550340.

The suppressive effects of landiolol administration on the occurrence of postoperative atrial fibrillation and tachycardia, and plasma IL-6 elevation in patients undergoing esophageal surgery: A randomized controlled clinical trial.

STUDY OBJECTIVE: To determine whether perioperative landiolol administration suppresses postoperative atrial fibrillation (AF) and the plasma cytokines elevation in patients undergoing esophageal cancer surgery. DESIGN: A prospective, randomized controlled trial. SETTING: Akita University Hospital, Akita, Japan, from April 2012 to January 2015. PATIENTS: Forty American Society of Anesthesiologists grade I-II patients undergoing elective esophagectomy. INTERVENTIONS: Patients were randomly divided into two groups, landiolol group (landiolol: 5µg/kg/min) and control group (the same volume of covered saline). Landiolol or saline was infused continuously from the induction of anesthesia until next morning. MEASUREMENTS: We examined the new onset of AF and sinus tachycardia, and measured plasma concentrations of cytokines (IL-1ß, IL-6, IL-8, IL-10, and TNF-α) just before surgery, at the end of surgery, the next day, and 2days after surgery. Data (mean±SD) were analyzed using two-way ANOVA followed by the Bonferroni"s test for post hoc comparison; a P<0.05 was considered statistically significant. MAIN RESULTS: Demographic data were similar between the landiolol and the control groups. The incidence of AF was significantly lower in the landiolol group (1/19=5.3%) compared with the control group (7/20=35%) as well as sinus tachycardia (landiolol group, 0/19=0% vs. control group, 5/20=25%). Plasma IL-6 level at the end of surgery was significantly lower in the landiolol group compared with the control group, but the other plasma cytokines levels were similar between the two groups during the entire study period. CONCLUSIONS: Perioperative landiolol administration suppressed the incidence of new-onset of AF as well as sinus tachycardia, and the plasma IL-6 elevation in patients undergoing esophageal cancer surgery.

11 analytically confirmed cases of mexedrone use among polydrug users.

INTRODUCTION: Mexedrone, 3-methoxy-2-(methylamino)-1-(4-methylphenyl)propan-1-one, is the alpha-methoxy-derivative of mephedrone (4-methyl-N-methyl cathinone). Mexedrone inhibits the re-uptake of serotonin and dopamine in a dose-dependent manner and has affinity for serotonin and dopamine membrane transporters and receptors (5-HT2 and D2 receptors), producing sympathomimetic effects similar to amfetamines. To date there are no published clinical reports on mexedrone use that are analytically confirmed. OBJECTIVE: To characterise the features of mexedrone use in patients who presented to our hospital after using a variety of psychoactive substances including mexedrone, with analytical confirmation in each case. METHODS: This is an observational case series. Urine toxicological screening using ultra-performance liquid chromatography with tandem mass spectrometry and exact mass time of flight was employed in all patients. RESULTS: A total of 305 cases were screened and mexedrone was identified in 11 urine samples. Agitation was the most common presenting feature in 10 of 11 patients. This was marked to the extent of aggression in some cases, with six patients requiring sedation and/or physical restraint. Delusions and hallucinations, often with paranoia, were observed in three cases with a prominent supernatural/demonic theme. None of these individuals had a history of psychosis. Seven of 11 patients were tachycardic >100 bpm. The median length of stay was 20 hours (range 2-77; IQR 4-33). Mexedrone alone is only likely to have been responsible for these clinical features in 2 cases; in two others mexedrone was found in high concentration along with substantial amounts of other stimulants. In 7 other cases other stimulants detected more likely explained the features. However, comprehensive analytical data enabled us to identify the full complement of agents contributing to the clinical presentation. CONCLUSIONS: Agitation was the predominant clinical feature in this case series and was often accompanied by a sinus tachycardia; mexedrone was primarily responsible in 2 patients but contributed substantially in two others. Patients typically recovered fully within 24 hours, unless they required sedation.

Optimal QT interval correction formula in sinus tachycardia for identifying cardiovascular and mortality risk: Findings from the Penn Atrial Fibrillation Free study.

BACKGROUND: The QT interval measures cardiac repolarization, and prolongation is associated with adverse cardiovascular outcomes and death. The exponential Bazett correction formula overestimates the QT interval during tachycardia. OBJECTIVE: We evaluated 4 formulas of QT interval correction in individuals with sinus tachycardia for the identification of coronary artery disease, heart failure, and mortality. METHODS: The Penn Atrial Fibrillation Free study is a large cohort study of patients without atrial fibrillation. The present study examined 6723 Penn Atrial Fibrillation Free study patients without a history of heart failure and with baseline sinus rate ≥100 beats/min. Medical records were queried for index clinical parameters, incident cardiovascular events, and all-cause mortality. The QT interval was corrected by using Bazett (QT/RR(0.5)), Fridericia (QT/RR(0.33)), Framingham [QT + 0.154 * (1000 - RR)], and Hodges (QT + 105 * (1/RR - 1)) formulas. RESULTS: In 6723 patients with a median follow-up of 4.5 years (interquartile range 1.9-6.4 years), the annualized cardiovascular event rate was 2.3% and the annualized mortality rate was 2.2%. QT prolongation was diagnosed in 39% of the cohort using the Bazett formula, 6.2% using the Fridericia formula, 3.7% using the Framingham formula, and 8.7% using the Hodges formula. Only the Hodges formula was an independent risk marker for death across the range of QT values (highest tertile: hazard ratio 1.26; 95% confidence interval 1.03-1.55). CONCLUSION: Although all correction formulas demonstrated an association between QTc values and cardiovascular events, only the Hodges formula identified one-third of individuals with tachycardia that are at higher risk of all-cause mortality. Furthermore, the Bazett correction formula overestimates the number of patients with a prolonged QT interval and was not associated with mortality. Future work may validate these findings and result in changes to automated algorithms for QT interval assessment.

Epidemiology and definition of inappropriate sinus tachycardia.

Inappropriate sinus tachycardia (IST) is a clinical syndrome lacking formal diagnostic criteria. It is generally defined as an elevated resting heart rate (HR; >90-100 bpm) with an exaggerated response to physical or emotional stress and a clearly sinus mechanism. Clinical manifestations are broad from a complete lack of symptoms to incapacitating incessant tachycardia. Now understood to be relatively prevalent, it is observed to have a generally benign prognosis, though symptoms may persist for years. Whether IST is a single discrete entity or a heterogeneous condition with overlap to other syndromes such as postural orthostatic tachycardia syndrome remains a matter of debate.

Reducción de frecuencia en la taquicardia sinusal en pacientes con trasplante cardiaco: ¿ha llegado el momento? / Slowing sinus tachycardia in heart transplant recipients: is it time?

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Transfusion-related adverse events in the Platelet Dose study.

BACKGROUND: How platelet (PLT) product characteristics such as dose, source (whole blood derived [WBD] vs. apheresis), storage duration, and ABO matching status affect the risks of transfusion-related adverse events (TRAEs) is unclear. Similarly, more information is needed to define how recipient characteristics affect the frequency of TRAEs after PLT transfusion. STUDY DESIGN AND METHODS: In the multicenter Platelet Dose ("PLADO") study, pediatric and adult hematology-oncology patients with hypoproliferative thrombocytopenia were randomized to receive low-dose (LD), medium-dose (MD), or high-dose (HD) PLT prophylaxis for a pretransfusion PLT count of not more than 10 × 10(9) /L. All PLT units (apheresis or WBD) were leukoreduced. Post hoc analyses of PLADO data were performed using multipredictor models. RESULTS: A total of 5034 PLT transfusions to 1102 patients were analyzed. A TRAE occurred with 501 PLT transfusions (10.0%). The most common TRAEs were fever (6.6% of transfusions), allergic or hypersensitivity reactions (1.9%), and sinus tachycardia (1.8%). Patients assigned HD PLTs were more likely than LD or MD patients to experience any TRAE (odds ratio for HD vs. MD, 1.50; 95% confidence interval, 1.10-2.05; three-group comparison p = 0.02). PLT source and ABO matching status were not significantly related to overall TRAE risk. Compared to a patient's first PLT transfusion, subsequent PLT transfusions were less likely to have a TRAE reported, primarily due to a lower risk of allergic or hypersensitivity reactions. CONCLUSION: The most important PLT unit characteristic associated with TRAEs was PLT dose per transfusion. HD PLTs may increase the risk of TRAEs, and LD PLTs may reduce the risk.

The incidence of supraventricular arrhythmias in patients with essential arterial hypertension--clinical and evolutive correlations.

AIM OF THE STUDY: The analysis of supraventricular rhythm disorders encountered in hypertensive patients and the establishment of correlations with other associated risk factors, duration of hypertension, the evolution and prognosis. MATERIAL AND METHODS: The study included a group of 110 patients, 80 men and 30 women, aged between 40 and 85, admitted in the 1st Cardiology Clinic during 2010-2013, diagnosed with essential arterial hypertension second and third degree. For the detection of arrhythmic events surface 12-lead ECG and 24-hour Holter monitoring were used. RESULTS AND DISCUSSION: Supraventricular arrhythmias encountered in the patients of the group were: ESA (mostly isolated, but also doublets, atrial bigeminy), atrial fibrillation, atrial flutter, sinus tachycardia, sinus bradycardia. Some arrhythmias may be an expression of the excessive activation of the sympathetic nervous system or on the contrary, vagal predominance, (ex. sinus bradycardia). Part of the arrhythmias occurring in hypertensive patients are hypertensive heart disease expressions, others are due to associated risk factors (smoking, alcohol) and even medication administered. In some cases, rhythm disturbances disappear with the normalization of the blood pressure; however, most of the times, the specific combination of anti-arrhythmic medication with antihypertensive medication is required. CONCLUSIONS: Supraventricular arrhythmias are frequently found in hypertensive patients, especially in those with long-term, uncontrolled hypertension, with impact on the evolution, prognosis and therapeutic management.

Hypertrophic cardiomyopathy: prognostic factors and survival analysis in 128 Egyptian patients.

BACKGROUND: Hypertrophic cardiomyopathy is an important cause of disability and death in patients of all ages. Egyptian children may differ from Western and Asian patients in the pattern of hypertrophy distribution, clinical manifestations, and risk factors. OBJECTIVES: The aim of our study was to report the clinical characteristics and outcomes of Egyptian children with hypertrophic cardiomyopathy studied over a 7-year duration and to determine whether the reported adult risk factors for sudden cardiac death are predictive of the outcome in these affected children. STUDY DESIGN AND METHODS: This retrospective study included 128 hypertrophic cardiomyopathy children. The data included personal history, family history, physical examination, baseline laboratory measurements, electrocardiogram, and Holter and echocardiographic results. Logistic regression analysis was used for the detection of risk factors of death. RESULTS: Fifty-one out of 128 patients died during the period of the study. Of the 51 deaths, 36 (70.5%) occurred in patients presenting before 1 year of age. Only eight patients had surgical intervention. Extreme left ventricular hypertrophy, that is, interventricular septal wall thickness or posterior wall thickness Z-score >6, sinus tachycardia, and supraventricular tachycardia were found to be independent risk factors for prediction of death in patients with hypertrophic cardiomyopathy. CONCLUSIONS: At our Egyptian tertiary care centre, hypertrophic cardiomyopathy has a relatively worse prognosis when compared with reports from Western and Asian series. Infants have a worse outcome than children presenting after the age of 1 year. A poorer prognosis in childhood hypertrophic cardiomyopathy is predicted by an extreme left ventricular hypertrophy, the presence of sinus tachycardia, and supraventricular tachycardia.

Frequent additional tachyarrhythmias in patients with inappropriate sinus tachycardia undergoing sinus node modification: an important cause of symptom recurrence.

BACKGROUND: Symptom recurrence following sinus node modification (SNM) for inappropriate sinus tachycardia (IST) remains significant despite achieving acute procedural success. The impact of non-IST tachyarrhythmias on symptom recurrence remains poorly characterized. OBJECTIVES: The objective was to determine the prevalence and nature of additional tachyarrhythmias preceding and following SNM for IST. METHODS: Consecutive patients with IST undergoing SNM at the University of Pennsylvania were studied. SNM was initially performed using an anatomic approach targeting the superolateral crista terminalis under intracardiac echocardiographic guidance and later using an electrophysiologic approach, targeting the site of the earliest right atrial activation during maximum heart rate (HR) with isoproterenol infusion. An effort was made to shift the site more caudally until a decrease of >25% in resting HR was achieved, with a blunted response to isoproterenol and flattening of the P-wave axis in leads III and aVF. Patients were followed for arrhythmia recurrence. Tachyarrhythmias were documented with electrocardiographic monitoring and then characterized during EP study. RESULTS: Thirty-three patients underwent SNM and were followed for a mean of 2.0 ± 1.5 years. During follow-up, 27% developed a non-IST tachyarrhythmia and 18% developed recurrent IST. Additionally, 42% of patients had a non-IST tachyarrhythmia prior to SNM. CONCLUSIONS: Non-IST tachyarrhythmias are common in patients with IST before and after SNM. A major reason for symptom recurrence following SNM is development of a non-IST tachyarrhythmia. These tachyarrhythmias should be detected and treated to optimize patient outcomes.

Cardiac disease in patients with mucopolysaccharidosis: presentation, diagnosis and management.

The mucopolysaccharidoses (MPSs) are inherited lysosomal storage disorders caused by the absence of functional enzymes that contribute to the degradation of glycosaminoglycans (GAGs). The progressive systemic deposition of GAGs results in multi-organ system dysfunction that varies with the particular GAG deposited and the specific enzyme mutation(s) present. Cardiac involvement has been reported in all MPS syndromes and is a common and early feature, particularly for those with MPS I, II, and VI. Cardiac valve thickening, dysfunction (more severe for left-sided than for right-sided valves), and hypertrophy are commonly present; conduction abnormalities, coronary artery and other vascular involvement may also occur. Cardiac disease emerges silently and contributes significantly to early mortality.The clinical examination of individuals with MPS is often difficult due to physical and, sometimes, intellectual patient limitations. The absence of precordial murmurs does not exclude the presence of cardiac disease. Echocardiography and electrocardiography are key diagnostic techniques for evaluation of valves, ventricular dimensions and function, which are recommended on a regular basis. The optimal technique for evaluation of coronary artery involvement remains unsettled.Standard medical and surgical techniques can be modified for MPS patients, and systemic therapies such as hematopoietic stem cell transplantation and enzyme replacement therapy (ERT) may alter overall disease progression with regression of ventricular hypertrophy and maintenance of ventricular function. Cardiac valve disease is usually unresponsive or, at best, stabilized, although ERT within the first few months of life may prevent valve involvement, a fact that emphasizes the importance of early diagnosis and treatment in MPS.

Impact of left ventricular ejection fraction on occurrence of ventricular events in defibrillator patients with coronary artery disease.

AIMS: Primary preventive implantable cardioverter defibrillator (ICD) therapy is indicated in patients with coronary artery disease (CAD) and left ventricular ejection fraction (LVEF) of ≤ 35%, but some patients in the major trials had LVEF in the range of 30-35%. We hypothesized that these patients constitute a lower-risk population and might derive less benefit from ICD therapy. METHODS AND RESULTS: In this retrospective study, patients with CAD in whom an ICD was implanted for primary prevention were studied. We determined the incidence of ICD therapies in two predefined LVEF cut-off groups (≤/>20%; ≤/>30%), predictors of ICD therapies, and overall mortality. A total of 536 patients were included: 88% male, age 63 ± 10 years, follow-up 30 ± 25 months. In all, 115 patients (22%) experienced appropriate ICD interventions; in 36% of them, the arrhythmia was treated with shock. Inappropriate therapy was delivered in 8%. Cumulative mortality at 5 years was 20%. Using our two cut-off levels, more ICD-therapies occurred in patients with poorer LVEF, but the difference was significant only with the cut-off value of ≤/>20%. Only 2 of 12 parameters were predictors of appropriate ICD therapy: age, odds ratio (OR) 1.047 (1.015-1.079) per year and QRS width, OR 1.014 per ms (1.004-1.024). CONCLUSION: Refined risk stratification using different LVEF cut-off levels is not helpful in patients with CAD and LVEF ≤ 35%. Mortality was lower than in randomized trials in this real-world setting, probably due to better drug treatment at implant.

[Risk of arrhythmia and domestic low-voltage electrical injury]. / Risque de trouble du rythme et électrisation par courant domestique.

AIM: Analysis of domestic low-voltage (220-240 V) electrical injury in children admitted to a pediatric emergency department to illustrate the low risk of initial or delayed risk of arrhythmia. MATERIAL AND METHODS: Retrospective study between 2001 and 2008 analyzing all children aged less than 15 years admitted for a low-voltage electrical injury. The data collected were age, sex, time and circumstances of the accident, time and day of admission, transport modalities, presence of risk factors for arrhythmia (transthoracic current, wet skin, tetany, loss of consciousness or neurological symptoms, and initial EKG abnormalities), injuries, EKG, muscular and/or cardiac enzyme values, progression and complications. For statistical analysis, data were entered in Microsoft Excel tables. Analysis was done with StatView5.1 (SAS Institute) and Epi Info 6.04fr (VF, ENSP epiconcept). In the descriptive analysis, the data are presented as mean values with SD, median and range. RESULTS: Forty-eight children were included. The mean annual number of admissions was equal to 6 (range, 3-12). The mean age was 6.2 + or - 4.3 years (median, 4.6 years). There was a male predominance: the overall sex ratio was 1.5, i.e., 3 before the age of 2 and 2.6 before the age of 10. The electrical injury occurred after contact with a wire or a connected cord or after the introduction of a metallic object in a wall socket. Ten children had risk factors of arrhythmia (mainly wet skin or thoracic pain). Twenty-nine children suffered from burns to the extremities (digits and hands, 70 %). At admission, 45 children had an EKG performed. The initial EKG was considered abnormal in 8 cases showing: sinusal tachycardia (n=4), incomplete right bundle branch block (n=4), and V(1) negative T waves (n=1). The EKG normalized within the first 12h. Hospitalization for cardiac monitoring was required for 18 children. No delayed arrhythmia occurred. In a mean time of 3.5h after the accident, a troponin dosage was given to 15 children and was normal in all cases. One child developed rhabdomyolysis and evolved without needing dialysis. CONCLUSION: After a low-voltage electrical injury, initial arrhythmia is not frequent, with often a nonspecific and transitory EKG expression; delayed arrhythmia is very rare. Children presenting to the emergency department after such an electrical accident, who are asymptomatic, without any risk factors for arrhythmia (wet skin, tetany, vertical pathway of the current, preexistent cardiological conditions, loss of consciousness) and with a normal initial EKG do not require cardiac monitoring.

Taquicardia auricular de vena pulmonar: características clínicas, electrocardiográficas y electrofisiológicas diferenciales / Atrial tachycardia originating from the pulmonary vein: clinical, electrocardiographic, and differential electrophysiologic characteristics

Introducción y objetivos. Las venas pulmonares (VP) son un origen frecuente de taquicardias auriculares (TA) ocasionalmente difícil de reconocer en el ECG. Analizamos las características diferenciales clínicas y electrofisiológicas, incluidas la duración y la presencia de melladura en la onda P sinusal, asociadas a las TA-VP. Métodos. Ochenta y siete pacientes sometidos a ablación de TA fueron incluidos y agrupados: TA-VP (grupo 1, n = 25), TA-VP asociada a fibrilación auricular (grupo 2, n = 18), otras TA izquierdas (grupo 3, n = 7) y TA derechas (grupo 4, n = 37). Resultados. El grupo 1 presentó edad media más joven (44 ± 14 años) que los grupos 2 a 4 (57 ± 9, 58 ± 12 y 53 ± 16 años, respectivamente; p < 0,05) y menor diámetro auricular izquierdo que otras TA izquierdas (grupos 2 y 3): 38 ± 4 vs. 48 ± 7 y 49 ± 5 mm, respectivamente (p < 0,05). Las TA-VP fueron debidas más frecuentemente a automatismo anormal/actividad desencadenada (p < 0,05) y presentaron ciclo auricular corto: 289 ± 45 y 280 ± 48 (grupos 1-2) vs. 392 ± 106 y 407 ± 87 ms (grupos 3-4; p < 0,05). La identificación de una onda P sinusal con duración ≥ 110 ms (sensibilidad/especificidad, 68%/69%) y melladura (79%/70%) en menores de 50 años con TA sin cardiopatía de base se asoció a TAVP (p < 0,05). Conclusiones. Una P sinusal prolongada y mellada en pacientes jóvenes con TA rápidas y sin cardiopatía predice un origen en VP (AU)

Introduction and objectives. Although atrial tachycardia (AT) frequently originates in the pulmonary vein, pulmonary vein atrial tachycardia (PV-AT) can be difficult to recognize on an ECG. The aim of this study was to identify clinical and electrophysiologic characteristics specific to PV-AT, including sinus P-wave duration and notching. Methods. The study included 87 patients who underwent AT ablation, divided into four groups: those with PV-AT alone (Group 1, n=25), those with PV-AT associated with atrial fibrillation (Group 2, n=18), and those with other forms of left AT (Group 3, n=7) and right AT (Group 4, n =37). Results. The mean age of patients in Group 1, at 44±14 years, was less than in Groups 2, 3 and 4, at 57±9, 58±12 and 53±16 years, respectively (P < .05) and the left atrial diameter, at 38±4 mm, was less than in the other left AT groups: 48±7 mm in Group 2 and 49±5 mm in Group 3 (P < .05). Overall, PV-AT was most frequently due to abnormal automaticity or triggered activity (P < .05) and presented with a short cycle length: 289±45 ms and 280±48 ms in Groups 1 and 2, respectively, versus 392±106 ms and 407 ± 87 ms in Groups 3 and 4, respectively (P < .05). In patients aged <50 years with at and no underlying heart disease pv-at was significantly p <.05) associated with a P-wave duration ≥110 ms (sensitivity 68%, specificity 69%) and P-wave notching (sensitivity 79%, specificity 70%). Conclusions. Sinus P-wave prolongation and notching in young patients with a rapid AT but without heart disease predicted an origin in the pulmonary vein (AU)

[Peculiar physiological reactions to +Gx loads of nonprofessional members of short-term missions to the ISS].

Physiological reactions to +Gx loads of 10 nonprofessional members of 8 to 12-d. missions to the ISS some of whom had partial health defciency were compared with data about space station MIR cosmonauts (n=10) who participated in flights of similar duration but were qualified as essentially healthy. Age of the ISS visitors varied between 29 and 60 years, whereas the MIR cosmonauts were 31 to 49 years old. Based on analysis of objective information, the ISS visitors were distinguished by much more pronounced sinus tachycardia and tachypnea during insertion and re-entry. There were several instances of pre-launch extrasystole arrhythmias that persisted during insertion and were, as a rule, more serious during re-entry. Also, descent from orbit caused more frequent cardiac rhythm disturbances, polymorphism and severity in these space flyers in comparison with the MIR cosmonauts. Particularly grave ECG deviations were observed in two 60-y.o. crew members. However, all these disturbances were episodic by character. These results suggest that development of individual programs of medical risk mitigation for nonprofessional flyers to the ISS should give regard for the status of cardiac rhythm regulation as re-entry g-loads may affect ECG dramatically. Besides, the analysis highlighted the necessity of more rigorous selection of aged candidates for ISS missions with partial health deficiency