EKG: J wave vs. J point

Interesting debate is published in JACC Apr 12, 2011 issue. The following two articles debate the issue.

Surawicz B, Macfarlane PW. Inappropriate and confusing electrocardiographic terms. J-wave syndrome and early repolarization. JACC 2011;57:1584-86.

Antzelevitch C, Yan GX, Viskin S. Rationale for the use of the terms J-wave syndromes and Early repolarization. JACC 2011;57:1587-90.

ICU: NGAL to detect Acute Kidney Injury

JACC 2011;57:1752-61

Article

Balloon Pulmonary Angioplasty - Adverse reactions (C3PO group)

Balloon Angioplasty and Stenting of Branch Pulmonary Arteries
Adverse Events and Procedural Characteristics: Results of a Multi-Institutional Registry
Ralf J. Holzer, et al.
Circ Cardiovasc Interv Apr 26, 2011 (Pub ahead of print)

Background—Pulmonary artery (PA) balloon angioplasty and/or stenting (PA rehabilitation) is one of the most common procedures performed in the cardiac catheterization laboratory, but comprehensive and consistently reported data on procedure-related adverse events (AE) are scarce.

Methods and Results—Data were prospectively collected using a multicenter registry (Congenital Cardiac Catheterization Project on Outcomes). All cases that included balloon angioplasty and/or stent implantation in a proximal or lobar PA position were included. Multivariate analysis was used to evaluate for independent predictors of AE and need for early reintervention. Between February 2007 and December 2009, 8 institutions submitted details on 1315 procedures with a PA intervention. An AE was documented in 22% with a high severity (level 3 to 5) AE in 10% of cases. Types of AE included vascular/cardiac trauma (19%), technical AE (15%), arrhythmias (15%), hemodynamic AE (14%), bleeding via endotracheal tube/reperfusion injury (12%), and other AE (24%). AE were classified as not preventable in 50%, possibly preventable in 41%, and preventable in 9%. By multivariate analysis, independent risk factors for level 3 to 5 AE were presence of ≥2 indicators of hemodynamic vulnerability, age below 1 month, use of cutting balloons, and operator experience of <10 years. Reintervention during the study period occurred in 22% of patients undergoing PA rehabilitation.

Conclusions—PA rehabilitation is associated with a 10% incidence of high-level severity AE. Hemodynamic vulnerability, young age, use of cutting balloons, and lower operator experience were significant independent risk factors for procedure-related AE.

Link to article

Innovation: Robotic Coronary Angioplasty

J Am Coll Cardiol Intv, 2011; 4:460-465,

First-in-Human Evaluation of a Novel Robotic-Assisted Coronary Angioplasty System

Juan F. Granada, MD*,,*, Juan A. Delgado, MD, Maria Paola Uribe, MSCE, Andres Fernandez, MD, Guillermo Blanco, MD, Martin B. Leon, MD, Giora Weisz, MD
* Skirball Center for Cardiovascular Research, Cardiovascular Research Foundation, New York, New York Corbic Research Institute, Envigado, Colombia Corbic Medical Center, Envigado, Columbia New York Presbyterian Hospital, Columbia University Medical Center, New York, New York (Email: jgranada@crf.org)

Background: A remote-control, robotic-assisted angioplasty system is under development to address some of the procedural challenges and occupational hazards associated with traditional PCI.

Methods:

CorPath 200 robotic system (Corindus, Inc., Natick, Massachusetts) consists of a remote cockpit & a multicomponent bedside unit that enables the operator to advance, retract, and rotate guidewires and rapid exchange catheters. The primary endpoint was device clinical success (30% residual stenosis) without in-hospital major adverse cardiac events.

Technical success was defined as the ability of the system to complete all the planned angioplasty steps on the basis of procedural segments. Patients were followed up to 30 days after angioplasty procedure.

Results: A total of 8 patients were enrolled in the study. The primary endpoint was achieved in all patients (100%). The technical success of the robotic system was 97.9% in completing 47 of 48 planned steps. There were no device- or procedure-related complications and no in-hospital or 30-day major adverse cardiac events. The operators rated the robotic system performances as equal to or better than manual procedures in 97.5% of the cases. The operator radiation exposure was 97% lower than the levels found at the standard table position.

Conclusions: Early clinical experience with a robotic-assisted angioplasty system demonstrated feasibility, safety, and procedural effectiveness comparable to manual operation. In addition, the total operator exposure to radiation was significantly low. A larger study is warranted to verify the safety and effectiveness of robotic-assisted percutaneous coronary intervention.

Wrist Circumference in Obese Children

Circulation. 2011;123:1757-1762

Wrist Circumference Is a Clinical Marker of Insulin Resistance in Overweight and Obese Children and Adolescents

Marco Capizzi, MD et al. Italy.

Background— Excess fat is one of the main determinants of insulin resistance, representing the metabolic basis for developing future cardiovascular disease. The aim of the current study was to find an easy-to-detect clinical marker of insulin resistance which can be used to identify young subjects at increased risk of cardiovascular disease.

Methods and Results— Four-hundred and seventy-seven overweight/obese children and adolescents (mean age 10.31±2.80 years) were consecutively enrolled. Standard deviation score body mass index, fasting biochemical parameters, and homeostasis model assessment of insulin resistance were evaluated. Statistical differences were investigated using multiple linear regression analysis. Manual measure of wrist circumference was evaluated in all children and adolescents. Fifty-one subjects, randomly selected, underwent nuclear magnetic resonance imaging of the wrist to evaluate transversal wrist area at the Lister tubercle level. A statistically significant association was found between manual measure of wrist circumference and insulin levels or homeostasis model assessment of insulin resistance (β=0.34 and 0.35, respectively; P<10–5 for both comparisons). These associations were more significant than those between SD score body mass index and insulin levels or homeostasis model assessment of insulin resistance (β=0.12 and 0.10, respectively; P0.02 for both comparisons). Nuclear magnetic resonance imaging acquisition clarified that the association between wrist circumference and insulin levels or homeostasis model assessment of insulin resistance reflected the association with bone tissue-related areas (P0.01 for both) but not with the adipose tissue ones (P>0.05), explaining 20% and 17% of the variances of the 2 parameters.

Conclusions— Our findings suggest a close relationship among wrist circumference, its bone component, and insulin resistance in overweight/obese children and adolescents, opening new perspectives in the prediction of cardiovascular disease.

Out of Hospital Cardiac Arrest in Children - Outcomes

J Am Coll Cardiol, 2011; 57:1822-1828, doi:10.1016/j.jacc.2010.11.054
© 2011 by the American College of Cardiology Foundation

Incidence, Causes, and Outcomes of Out-of-Hospital Cardiac Arrest in Children

A Comprehensive, Prospective, Population-Based Study in the Netherlands

Abdennasser Bardai, MD et al.

Email: h.l.tan@amc.uva.nl).

Objectives: This study sought to determine comprehensively the incidence of pediatric out-of-hospital cardiac arrest (OHCA) and its contribution to total pediatric mortality, the causes of pediatric OHCA, and the outcome of resuscitation of pediatric OHCA patients.

Background: There is a paucity of complete studies on incidence, causes, and outcomes of pediatric OHCA.

Methods: In this prospective, population-based study, OHCA victims younger than age 21 years in 1 province of the Netherlands were registered through both emergency medical services and coroners over a period of 4.3 years. Death certificate data on total pediatric mortality, survival status, and neurological outcome at hospital discharge also were obtained.

Results: With a total mortality of 923 during the study period and 233 victims of OHCA (including 221 who died and 12 who survived), OHCA caused 24% (221 of 923) of total pediatric mortality. Natural causes of OHCA amounted to 115 (49%) cases, with cardiac causes being most prevalent (n = 90, 39%). The incidence of pediatric OHCA was 9.0 per 100,000 pediatric person-years (95% confidence interval: 7.8 to 10.3), whereas the incidence of pediatric OHCA from cardiac causes was 3.2 (95% confidence interval: 2.5 to 3.9). Of 51 resuscitated patients, 12 (24%) survived; among survivors, 10 (83%) had a neurologically intact outcome.

Conclusions: Out-of-hospital cardiac arrest accounts for a significant proportion of pediatric mortality, and cardiac causes are the most prevalent causes of OHCA. The vast majority of OHCA survivors have a neurologically intact outcome.

Editorial:
J Am Coll Cardiol, 2011; 57:1829-1830, doi:10.1016/j.jacc.2010.11.055

Improved Outcomes for Cardiac Arrest in Children

Share the Baton With the Bystander*

Sumeet S. Chugh, MD*
Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California

* Reprint requests and correspondence: Dr. Sumeet S. Chugh, The Heart Institute, 5702 South Tower, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, California 90048 (Email: sumeet.chugh@cshs.org).

Key Words: bystander • cardiac arrest • death • pediatric • population • sudden • survival

We continue to grapple with the complexities of preventing and resuscitating out-of-hospital cardiac arrests (OHCAs). Of these, cardiac arrests among children clearly have the most devastating effect on communities. The study from Bardai et al. (1) based in North Holland, the Netherlands, is an important investigation with some caveats and several lessons that merit some discussion.
This was a prospective study in a community of 2.4 million people, with 588,389 residents younger than 21 years of age. It is important to recognize that the manner in which Bardai et al. (1) presented their data tends to overestimate the actual incidence of pediatric OHCA. Their definition of OHCA was very broad and included natural causes (cardiac and noncardiac) as well as all unnatural causes of OHCA, such as traffic accidents and violent trauma. Another reason for possible overestimation relates to their inclusion of subjects 20 years of age or younger (the 18- to 20-year age group represented 25% of total OHCAs). Nonetheless, their findings indicate that similar to adults, there is likely to be geographic variation in the annual incidence of pediatric OHCA. Even if we focus on the subgroup of natural OHCA of likely cardiac cause, the annual incidence ranges from 3.2 per 100,000 children in North Holland, the Netherlands, to 7.5 per 100,000 in Portland, Oregon (2). For the purpose of reporting, it is helpful to make a clear separation between OHCA resulting from natural causes versus that resulting from unnatural causes, because the approach to prevention is distinctly different for each category. Although childhood cardiac arrests invariably are the most devastating of the OHCAs, fortunately, they are relatively uncommon, representing 1.3% and 2.8% of all OHCAs in North Holland, the Netherlands, and Portland, Oregon, respectively.

Similar to adults, the vast majority of pediatric OHCAs (78% in the North Holland study) are related to cardiac causes. However, the age distribution of North Holland pediatric OHCAs in this subgroup is distinct from that of earlier reports. The significantly lower proportion of infants (39%) is a departure from the expected highest rates in the younger than 1 year age group compared with older pediatric age groups, and the authors point us to published data that suggests a 5.7-fold higher incidence of sudden infant death syndrome (SIDS) in the United States compared with the Netherlands (3). Because they do not provide us with any information regarding what proportion of infants had a diagnosis of SIDS, we have to assume that the rates of SIDS are lower compared with those of other communities. Although successful SIDS prevention through education and modification of behavior and societal or cultural practices is a well-established strategy, the North Holland findings could indicate that there is significant room for improvement in prevention of SIDS in other parts of the world.

The most striking findings of the North Holland study relate to the outcome of resuscitated pediatric OHCAs, both in terms of survival to hospital discharge as well as neurologic recovery. The overall rate of survival to hospital discharge was 24% (12 of 51), and the overall rate of neurologic recovery was 83%. When taken in the context of the existing literature (6.4% survival in a recent large North American experience [4]), this is an enviable rate of survival and neurologic recovery for pediatric OHCAs. OHCAs with ventricular tachycardia or ventricular fibrillation, as opposed to pulseless electrical activity or asystole, are significantly more likely to survive, and Bardai et al. (1) report high rates of ventricular tachycardia or ventricular fibrillation (36% overall, with 83% among adolescents). However, these rates do not seem to be explained by the somewhat modest response times that are in the range of 11 to 12 min. It is likely, therefore, that this favorable outcome is attributable to the high rates of witnessed collapse, bystander cardiopulmonary resuscitation, and use of automated external defibrillators. Although there are other factors, such as population density and overall education level of residents, that likely contribute to the survival advantage enjoyed by North Holland pediatric residents, this solid outcome clearly reflects successful bystander education in a well-deployed emergency medical response system.

Bardai et al. (1) need to be congratulated for their impressive work in a sizable community. Although their community may have some specific characteristics that are not transferable to other regions, the excellent survival and neurologic recovery rates are unmistakable and demonstrate the feasibility of attaining better outcomes for pediatric OHCA, especially by increasing awareness within the community. Improved bystander CPR, as well as use of automated external defibrillators, are likely to be of particular benefit for resuscitation in children. Simultaneously, because most naturally occurring pediatric sudden deaths are likely to be cardiac, we also must continue to focus our efforts on prevention. Although SIDS is acknowledged to be a complex disorder with multiple causes, major inroads have also been made by focused community-based educational interventions (3). In addition, the younger the age, the higher the likelihood of a genetic cause. A renewed emphasis needs to be placed on community health care providers obtaining detailed family histories with appropriate referral for genetic screening and counseling. In the event of unexplained sudden deaths, a molecular autopsy (5,6) should become part of the community forensic investigation as a critical means of enhancing prevention for family members who are left behind.




Footnotes

Dr. Chugh is the Pauline and Harold Price Professor of Cardiac Electrophysiology at the Cedars-Sinai Heart Institute, Los Angeles, California; there are no other relationships to disclose.

* Editorials published in the Journal of the American College of Cardiology reflect the views of the authors and do not necessarily represent the views of JACC or the American College of Cardiology.


References

1. Bardai A, Berdowski J, van der Werf C, et al. Incidence, causes, and outcomes of out-of-hospital cardiac arrest in children: a comprehensive, prospective, population-based study in the Netherlands J Am Coll Cardiol 2011;57:1822-1828.[Abstract/Free Full Text]
2. Chugh SS, Reinier K, Balaji S, et al. Population-based analysis of sudden death in children: the Oregon Sudden Unexpected Death Study Heart Rhythm 2009;6:1618-1622.[CrossRef][Web of Science][Medline]
3. Moon RY, Horne RS, Hauck FR. Sudden infant death syndrome Lancet 2007;370:1578-1587.[CrossRef][Web of Science][Medline]
4. Atkins DL, Everson-Stewart S, Sears GK, et al. Epidemiology and outcomes from out-of-hospital cardiac arrest in children: the Resuscitation Outcomes Consortium Epistry-Cardiac Arrest Circulation 2009;119:1484-1491.[Abstract/Free Full Text]
5. Chugh SS, Senashova O, Watts A, et al. Postmortem molecular screening in unexplained sudden death J Am Coll Cardiol 2004;43:1625-1629.[Abstract/Free Full Text]
6. Tan HL, Hofman N, van Langen IM, van der Wal AC, Wilde AA. Sudden unexplained death: heritability and diagnostic yield of cardiological and genetic examination in surviving relatives Circulation 2005;112:207-213.[Abstract/Free Full Text]

UK is better than US in Health Status

Am. J. Epidemiol. (2011) 173 (8):858-865.

Health Across the Life Span in the United States and England

1. Melissa L. Martinson*,
2. Julien O. Teitler and
3. Nancy E. Reichman

Abstract

This study systematically compared health indicators in the United States and England from childhood through old age (ages 0–80 years).

Data were from the 1999–2006 National Health and Nutrition Examination Survey for the United States (n = 39,849) and the 2003–2006 Health Survey for England (n = 69,084).

Results:

Individuals in the United States have higher rates of most chronic diseases and markers of disease than their same-age counterparts in England.

Differences at young ages are as large as those at older ages for most conditions, including obesity, low high-density lipoprotein cholesterol, high cholesterol ratio, high C-reactive protein, hypertension (for females), diabetes, asthma, heart attack or angina (for females), and stroke (for females).

For males, heart attack or angina is higher in the United States only at younger ages, and hypertension is higher in England than in the United States at young ages. The patterns were similar when the sample was restricted to whites, the insured, nonobese, nonsmoking nondrinkers, and specific income categories and when stratified by normal weight, overweight, and obese weight categories.

The findings from this study indicate that US health disadvantages compared with England arise at early ages and that differences in the body weight distributions of the 2 countries do not play a clear role.

Intro...

Per capita spending on health care is higher in the United States than in any other country and double that in the United Kingdom (1). Despite the high rate of spending, adults aged 50 years or older in the United States have significantly worse health status (2–4) and lower life expectancy (1, 5) than those in England. Individuals in the United States also have higher mortality rates throughout the life course until at least age 75 years (based on 2007 mortality statistics) (6, 7). Why health status differs so dramatically in these 2 countries, which share much in terms of history and culture, is an unresolved puzzle.

Link to the article

T wave components in LQTS 1

• CIRCEP.110.958827Published online before print April 21, 2011
• Original Article

Detection of Extra-Components of T Wave by Independent Component Analysis in Congenital Long QT Syndrome

1. Hitoshi Horigome,
2. Yasuhiro Ishikawa,
3. Junko Shiono,
4. Mari Iwamoto,
5. Naokata Sumitomo and
6. Masao Yoshinaga

1. ¹ University of Tsukuba, Tsukuba, Ibaraki, Japan;
2. ² Ishikawa Clinic & Toyohashi University of Technology, Toyohashi, Aichi, Japan;
3. ³ Ibaraki Children's Hospital, Mito, Ibaraki, Japan;
4. ⁴ Yokohama City University, Yokohama, Japan;
5. ⁵ Nihon University, School of Medicine, Tokyo, Japan;
6. ⁶ National Hospital Organization Kagoshima Medical Center, Kagoshima, Jap
   hhorigom@md.tsukuba.ac.jp

Abstract

Background—The main EKG criteria for the diagnosis of long QT syndrome (LQTS) include abnormal T wave morphology as well as prolonged QT interval. The T wave in LQTS probably includes additional components of myocardial repolarization process, which is derived from aberrant ion currents. We investigated whether independent component analysis (ICA) can extract such abnormal repolarization component.

Methods and Results—Digital EKG data were obtained as time series from 10 channels using 20 surface electrodes in 22 patients with genetically-confirmed LQTS type 1 (LQT1) and 30 normal subjects. In each case, T wave area was analyzed by radical ICA after noise reduction by the wavelet thresholding method. Furthermore, inverse ICA was applied to determine the origin of each independent component (IC). Radical ICA revealed that a T-wave consisted of four basic ICs in all control subjects, whereas five or more (mostly 6) ICs were identified in all 22 cases of LQT1. The extra ICs, which were not evident in normal subjects, were assumed to contribute to the formation of abnormal T-wave morphology. The extra ICs were identified even in those patients with normal QTc values and those taking β-blockers. Inverse ICA indicated that the additional ICs originate predominantly from the late phase of the T wave of the left ventricle.

Conclusions—Extra ICs appear during repolarization in all LQT1 patients but not in normal subjects. ICA is a potentially useful multivariate statistical method to differentiate LQT1 patients from normal subjects.

Heart risk factors high in young Indian adults

By Amy Norton
NEW YORK Wed Apr 20, 2011 6:29pm EDT

NEW YORK (Reuters Health) - More and more, young urban adults in India are developing obesity, high blood pressure and diabetes -- suggesting that rising rates of heart disease could be in the future, a new study finds.
Among 1,100 young adults from New Delhi, all three conditions became steadily more common over the 7 years of the study. And all are known to contribute to heart disease.
At the outset, when the average study participant was 29 years old, about 50 percent had waistlines that fit the criteria for abdominal obesity. Seven years later, that was true for 70 percent.
Meanwhile, rates of high blood pressure rose from 11 percent to 34 percent among men, and from 5 percent to 15 percent among women. Diabetes also became a growing problem -- with the rate rising from 5 percent to 12 percent among men, and from 3.5 percent to 7 percent among women.
Those "remarkable changes" in such a short time suggest that these young adults could have high rates of heart disease and stroke down the road, the researchers warn.
The findings, reported in the Journal of the American College of Cardiology, add to a bleak outlook for Indians' heart health.
The country of 1 billion-plus was estimated to account for 60 percent of the world's heart disease cases in 2010. And a recent study found that people in India and other South Asian countries suffer their first heart attack at age 53, on average -- 6 years earlier than the rest of the world.
Dr. Dorairaj Prabhakaran, who worked on the new study, was not surprised at how common heart disease risk factors were even in this young population.
"Given the rapid socioeconomic and demographic transitions in India, I was not surprised at the high incidence rates," Prabhakaran, a cardiologist at the Center for Chronic Disease Control in New Delhi, told Reuters Health in an email.
Western-style diets often catch the blame for feeding obesity and its associated health problems, Prabhakaran noted. But such eating habits are not that common in India.
"Many popular Indian foods are unhealthy, as they are rich in sugar and saturated fat," said Prabhakaran.
He added that many traditional Indian foods are high in salt, while popular inexpensive foods like biscuits and other baked goods contain trans-fat -- which can not only raise "bad" LDL cholesterol but also lower heart-healthy HDL cholesterol.
Bigger portions of those foods, decreasing physical activity, and other heart threats like smoking could be behind the current findings.
And while the study looked only at young adults in New Delhi, Prabhakaran said that heart risk factors in rural areas of southern India have risen quickly in the last decade and are near the levels seen in urban areas.
"Reducing cardiovascular disease and its risk factors requires a policy response," Prabhakaran said, "particularly tobacco control, making fruits and vegetables available locally and affordable, and an enabling environment to improve physical activity."
Heart disease and its risk factors put a "huge" financial burden on the Indian people and healthcare system, Prabhakaran and his colleagues point out.
The annual cost of treating diabetes, for example, consumes anywhere from 5 percent to 34 percent of personal income in India.
An editorial published with the study agreed on the need for tobacco control and other public policies aimed at improving heart health in India.
Health education is not enough because "smoking, sedentariness, and poor diet do not arise in a vacuum," write Drs. Gilles Paradis, of McGill University in Montreal, Canada, and Arnaud Chiolero of the University of Lausanne in Switzerland.
"The task is daunting," they write, "but we have a moral obligation to support the global fight against (cardiovascular disease) and chronic diseases, which are the pandemic of the twenty-first century."
SOURCE: Journal of the American College of Cardiology, April 26, 2011.

Survival difference based on ethnicity

Published online April 18, 2011
PEDIATRICS (doi:10.1542/peds.2010-2702)

Racial/Ethnic Disparities in Risk of Early Childhood Mortality Among Children With Congenital Heart Defects

Wendy N. Nembhard, PhD, Jason L. Salemi, MPH, Mary K. Ethen, MPH, David E. Fixler, MD, MSc, Angela DiMaggio, BS, Mark A. Canfield, PhD

BACKGROUND Infants with congenital heart defects (CHDs) have increased risk of childhood morbidity and mortality. However, little is known about racial/ethnic differences in early childhood mortality.

PATIENTS AND METHODS We conducted a retrospective cohort study with data from the Texas Birth Defect Registry on 19 530 singleton, live-born infants with a CHD and born January 1, 1996, to December 31, 2003, to non-Hispanic (NH) white, NH black, and Hispanic women. Texas Birth Defect Registry data were linked to Texas death records and the National Death Index to ascertain deaths between January 1, 1996, and December 31, 2005. Kaplan-Meier survival estimates were computed, and hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated from multivariable Cox-proportional hazard regression models to determine the effect of maternal race/ethnicity on mortality for selected CHD phenotypes.

RESULTS After adjusting for covariates, compared with NH white children, NH black children had increased early childhood mortality risk for transposition of the great arteries (HR: 2.04 [95% CI: 1.40–2.97]), tetralogy of Fallot (HR: 1.85 [95% CI: 1.09–3.12]), pulmonary valve atresia without ventricular septal defect (VSD) (HR: 2.60 [95% CI: 1.32–5.12]), VSD (HR: 1.56 [95% CI: 1.19–2.03]), and atrial septal defect (HR: 1.34 [95% CI: 1.08–1.66]). Hispanic children had higher mortality risk for pulmonary valve atresia without VSD (HR: 1.76 [95% CI: 1.06–2.91]) and hypoplastic left heart syndrome (HR: 1.51 [95% CI: 1.13–2.02]).

CONCLUSIONS We provide evidence that supports racial/ethnic disparities in early childhood mortality among infants with CHDs. Identifying infants with the greatest risk of early childhood mortality will facilitate development of interventions and policies to mitigate these risks.