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Obesity is associated with additional left ventricular hypertrophy (LVH) in adults with hypertrophic cardiomyopathy (HCM). It is not known whether obesity can lead to further LVH in children with HCM. Echocardiographic LV dimensions were determined in 504 children with HCM. Measurements of interventricular septal thickness (IVST) and posterior wall thickness (PWT), and patients' weight and height were recorded. Obesity was defined as a body mass index (BMI) >= 99th percentile for age and sex. IVST data was available for 498 and PWT data for 484 patients. Patient age ranged from 2 to 20 years (mean +/- SD, 12.5 +/- 3.9) and 340 (68%) were males. Overall, patient BMI ranged from 7 to 50 (22.7 +/- 6.1). Obesity (BMI 18-50, mean 29.1) was present in 140 children aged 2-19.6 (11.3 +/- 4.1). The overall mean IVST was 20.5 +/- 9.6 mm and the overall mean PWT was 11.0 +/- 8.4 mm. The mean IVST in the obese patients was 21.6 +/- 10.0 mm and mean PWT was 13.3 +/- 14.7 mm. The mean IVST in the non-obese patients was 20.1 +/- 9.5 mm and mean PWT was 10.4 +/- 4.3 mm. Obesity was not significantly associated with IVST (p = 0.12), but was associated with increased PWT (0.0011). Obesity is associated with increased PWT but not IVST in children with HCM. Whether obesity and its impact on LVH influences clinical outcomes in children with HCM needs to be studied.

BACKGROUND Predictors of risk of lethal arrhythmic events (LAE) is poorly understood and may differ from adults in children with hypertrophic cardiomyopathy (HCM). OBJECTIVE The purpose of this study was to determine predictors of LAE in children with HCM. METHODS A retrospective data collection was performed on 446 children and teenagers 20 years and younger (290 [65%] male; mean age 10.1 +/- 5.7 years) with idiopathic HCM from 35 centers. Patients were classified as group 1 (HCM with LAE) if having a secondary prevention implantable cardioverter-defibrillator (ICD) or primary prevention ICD with appropriate interventions or group 2 (HCM without LAE) if having a primary prevention ICD without appropriate interventions. RESULTS There were 152 children (34%) in group 1 and 294 (66%) in group 2. Risk factors for group 1 by univariate analysis were septal thickness, posterior left ventricular (LV) wall thickness, lower LV outflow gradient, and Q wave > 3 mm in inferior electrocardiographic leads. Factors not associated with LAE were family history of SCD, abnormal blood pressure response to exercise, and ventricular tachycardia on ambulatory electrocardiographic monitoring. Risk factors for SCD by multivariate analysis were age at ICD placement (hazard ratio [HR] 0.9; P = .0025), LV posterior wall thickness z score (HR 1.02; P < .005), and LV outflow gradient < 30 mm Hg (HR 2.0; P < .006). LV posterior wall thickness z score >= 5 was associated with LAE. CONCLUSION Risk factors for LAE appear different in children compared to adults. Conventional adult risk factors were not significant in children. Further prospective studies are needed to improve risk stratification for LAE in children with HCM.

Obesity is associated with additional left ventricular hypertrophy (LVH) in adults with hypertrophic cardiomyopathy (HCM). It is not known whether obesity can lead to further LVH in children with HCM. Echocardiographic LV dimensions were determined in 504 children with HCM. Measurements of interventricular septal thickness (IVST) and posterior wall thickness (PWT), and patients' weight and height were recorded. Obesity was defined as a body mass index (BMI) >= 99th percentile for age and sex. IVST data was available for 498 and PWT data for 484 patients. Patient age ranged from 2 to 20 years (mean +/- SD, 12.5 +/- 3.9) and 340 (68%) were males. Overall, patient BMI ranged from 7 to 50 (22.7 +/- 6.1). Obesity (BMI 18-50, mean 29.1) was present in 140 children aged 2-19.6 (11.3 +/- 4.1). The overall mean IVST was 20.5 +/- 9.6 mm and the overall mean PWT was 11.0 +/- 8.4 mm. The mean IVST in the obese patients was 21.6 +/- 10.0 mm and mean PWT was 13.3 +/- 14.7 mm. The mean IVST in the non-obese patients was 20.1 +/- 9.5 mm and mean PWT was 10.4 +/- 4.3 mm. Obesity was not significantly associated with IVST (p = 0.12), but was associated with increased PWT (0.0011). Obesity is associated with increased PWT but not IVST in children with HCM. Whether obesity and its impact on LVH influences clinical outcomes in children with HCM needs to be studied.

BACKGROUND Predictors of risk of lethal arrhythmic events (LAE) is poorly understood and may differ from adults in children with hypertrophic cardiomyopathy (HCM). OBJECTIVE The purpose of this study was to determine predictors of LAE in children with HCM. METHODS A retrospective data collection was performed on 446 children and teenagers 20 years and younger (290 [65%] male; mean age 10.1 +/- 5.7 years) with idiopathic HCM from 35 centers. Patients were classified as group 1 (HCM with LAE) if having a secondary prevention implantable cardioverter-defibrillator (ICD) or primary prevention ICD with appropriate interventions or group 2 (HCM without LAE) if having a primary prevention ICD without appropriate interventions. RESULTS There were 152 children (34%) in group 1 and 294 (66%) in group 2. Risk factors for group 1 by univariate analysis were septal thickness, posterior left ventricular (LV) wall thickness, lower LV outflow gradient, and Q wave > 3 mm in inferior electrocardiographic leads. Factors not associated with LAE were family history of SCD, abnormal blood pressure response to exercise, and ventricular tachycardia on ambulatory electrocardiographic monitoring. Risk factors for SCD by multivariate analysis were age at ICD placement (hazard ratio [HR] 0.9; P = .0025), LV posterior wall thickness z score (HR 1.02; P < .005), and LV outflow gradient < 30 mm Hg (HR 2.0; P < .006). LV posterior wall thickness z score >= 5 was associated with LAE. CONCLUSION Risk factors for LAE appear different in children compared to adults. Conventional adult risk factors were not significant in children. Further prospective studies are needed to improve risk stratification for LAE in children with HCM.

This thesis identifies five common characteristics of successful post-World War II insurgencies: (1) a cause to fight for, (2) local populace support, (3) weakness in the authority, (4) favorable geographic condictions, and (5) external support during the middle and later stages of an insurgency. This list of characteristics is incomplete for current and future insurgencies and a sixth characteristic, (6) an information advantage, is necessary. For this study, 72 post-World War II insurgencies are identified, of which 11 are classified as failed insurgencies. Of these failed insurgencies, 6 were selected for analysis using the above 6 charactersitics of an insurgency in order to determine any trends in their failure. The 6 selected failed insurgencies are: Greek Civil War, Philippines (HUK), Malayan Emergency, Kenya Emergency, Dhofar Rebellion, and Bolivia. This research determined that no one characteristic stands out as the key for defeating an insurgency. Counterinsurgent forces must consider and take into account all 6 charactersitics and plan accordingly. It is further determined that 3 of the characteristics: local populace support, external support, and information advantage must be reduced to a significate disadvantage for an insurgency in order for an insurgency to fail., http://archive.org/details/whyinsurgentsfai109453570, US Army (USA) author., Approved for public release; distribution is unlimited.

This thesis identifies five common characteristics of successful post- World War II insurgencies: (1) a cause to fight for, (2) local populace support, (3) weakness in the authority, (4) favorable geographic conditions, and (5) external support during the middle and later stages of an insurgency. This list of characteristics is incomplete for current and future insurgencies and a sixth characteristic, (6) an information advantage, is necessary. For this study, 72 post-World War II insurgencies are identified, of which 11 are classified as failed insurgencies. Of these 11 failed insurgencies, 6 were selected for analysis using the above 6 characteristics of an insurgency in order to determine any trends in their failure. The 6 selected failed insurgencies are: Greek Civil War, Philippines (Huk), Malayan Emergency, Kenya Emergency, Dhofar Rebellion, and Bolivia. This research determined that no one characteristic stands out as the key for defeating an insurgency. Counterinsurgent forces must consider and take into account all 6 characteristics and plan accordingly. It is further determined that 3 of the characteristics: local populace support, external support, and information advantage, must be reduced to a significant disadvantage for an insurgency in order for an insurgency to fail.

This thesis identifies five common characteristics of successful post-World War II insurgencies: (1) a cause to fight for, (2) local populace support, (3) weakness in the authority, (4) favorable geographic condictions, and (5) external support during the middle and later stages of an insurgency. This list of characteristics is incomplete for current and future insurgencies and a sixth characteristic, (6) an information advantage, is necessary. For this study, 72 post-World War II insurgencies are identified, of which 11 are classified as failed insurgencies. Of these failed insurgencies, 6 were selected for analysis using the above 6 charactersitics of an insurgency in order to determine any trends in their failure. The 6 selected failed insurgencies are: Greek Civil War, Philippines (HUK), Malayan Emergency, Kenya Emergency, Dhofar Rebellion, and Bolivia. This research determined that no one characteristic stands out as the key for defeating an insurgency. Counterinsurgent forces must consider and take into account all 6 charactersitics and plan accordingly. It is further determined that 3 of the characteristics: local populace support, external support, and information advantage must be reduced to a significate disadvantage for an insurgency in order for an insurgency to fail.

This report utilizes most recent meteoroid flux data and illustrates the method used in calculating the probability of meteoroid puncture for a space-suited crewman in earth orbit. An example of the method is shown and uncertainties in the prediction are reviewed. Finally, guidelines are presented that could be followed in planning an experimental program of penetration studies on space suit materials intended to resolve some of these areas of uncertainty. (Author)