Endovascular Repair of Descending Thoracic Aorta in Loeys-Dietz II Syndrome

Loeys-Dietz syndrome (LDS) is an autosomal dominant disorder that is predominantly characterized by involvement of the aorta, manifesting as aneurysmal dilatation or aortic dissection. Patients with LDS manifest with spontaneous aneurysms and dissections of central and peripheral arterial beds. We present 2 cases of young male patients with Loeys-Dietz II aortopathy, who manifested with spontaneous intimal tear of descending thoracic aorta and contained aortic rupture. Both patients were managed by endovascular repair, with collaborative efforts of teams comprising interventional cardiologists and radiologists, and a vascular surgeon.

Advanced Heart Failure With Preserved Systolic Function in Nonobstructive Hypertrophic Cardiomyopathy

Background—

In hypertrophic cardiomyopathy (HCM), heart transplant has been predominantly confined to patients with systolic dysfunction. An underappreciated HCM subset comprises patients with preserved left ventricular (LV) systolic function who may also require consideration for transplantation. Therefore, we sought to define the clinical profile and occurrence of advanced heart failure among patients with nonobstructive HCM and preserved systolic function.

Methods and Results—

Databases from 2 referral centers comprising 2100 HCM patients were interrogated. Forty-six nonobstructive HCM patients (2.2%) either received or were listed for heart transplant, including 20 with normal systolic function (ejection fraction ≥50%). At transplant listing, these 20 patients were 42±13 years old, each in New York Heart Association functional class III/IV with ejection fraction of 62±7%. LV was hypertrophied with maximum wall thickness of 22±4 mm and nondilated (end-diastolic dimension, 39±7 mm). Cardiovascular magnetic resonance in 10 (of 15) patients showed no or minimal fibrosis (≤5% LV mass). Elevated LV end-diastolic or pulmonary capillary wedge pressure, consistent with diastolic dysfunction, was present in 15 patients (75%). LV filling was impaired by echocardiographic measures in all patients, including a restrictive inflow pattern in 8 (40%). In 2 patients, traditional criteria for transplant were absent, including peak V O 2 >14 mL/kg/min. Heart transplantation was performed in 12 patients with each alive and without cardiovascular symptoms, 2.3±1.7 years later.

Conclusions—

A previously under-recognized segment of the broad HCM clinical spectrum consists of nonobstructive patients with advanced heart failure, in the presence of preserved systolic function, for whom heart transplant is the sole definitive therapeutic option.

Cocaine-related aortic dissection: lessons from the International Registry of Acute Aortic Dissection

BACKGROUND

Acute aortic dissection associated with cocaine use is rare and has been reported predominantly as single cases or in small patient cohorts.

METHODS

Our study analyzed 3584 patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2012. We divided the population on the basis of documented cocaine use (C+) versus non cocaine use (C-) and further stratified the cohorts into type A (33 C+/2332, 1.4%) and type B (30 C+/1252, 2.4%) dissection.

RESULTS

C+ patients presented at a younger age and were more likely to be male and black. Type B dissections were more common among C+ patients than in C- patients. Cocaine-related acute aortic dissection was reported more often at US sites than at European sites (86.4%, 51/63 vs 13.6%, 8/63; P < .001). Tobacco use was more prevalent in the C+ cohort. No differences were seen in history of hypertension, known atherosclerosis, or time from symptom onset to presentation. Type B C+ patients were more likely to be hypertensive at presentation. C+ patients had significantly smaller ascending aortic diameters at presentation. Acute renal failure was more common in type A C+ patients; however, mortality was significantly lower in type A C+ patients.

CONCLUSIONS

Cocaine use is implicated in 1.8% of patients with acute aortic dissection. The typical patient is relatively young and has the additional risk factors of hypertension and tobacco use. In-hospital mortality for those with cocaine-related type A dissection is lower than for those with non cocaine-related dissection, likely due to the younger age at presentation.

Moderate to vigorous physical activity interactions with genetic variants and body mass index in a large US ethnically diverse cohort

BACKGROUND

Little is known about the interaction between genetic and behavioural factors during lifecycle risk periods for obesity and how associations vary across race/ethnicity.

OBJECTIVE

The objective of this study was to examine joint associations of adiposity-related single-nucleotide polymorphisms (SNPs) and moderate to vigorous physical activity (MVPA) with body mass index (BMI) in a diverse adolescent cohort.

METHODS

Using data from the National Longitudinal Study of Adolescent Health (n = 8113: Wave II 1996; ages 12-21, Wave III; ages 18-27), we assessed interactions of 41 well-established SNPs and MVPA with BMI-for-age Z-scores in European Americans (EA; n = 5077), African-Americans (AA; n = 1736) and Hispanic Americans (HA; n = 1300).

RESULTS

Of 97 assessed, we found nominally significant SNP-MVPA interactions on BMI-for-age Z-score in EA at GNPDA2 and FTO and in HA at LZTR2/SEC16B. In EA, the estimated effect of the FTO risk allele on BMI-for-age Z-score was lower (β = -0.13; 95% confidence interval [CI]: 0.08, 0.18) in individuals with ≥5 vs. <5 (β = 0.24; CI: 0.16, 0.32) bouts of MVPA per week (P for interaction 0.02). Race/ethnicity-pooled meta-analysis showed nominally significant interactions for SNPs at TFAP2B, POC5 and LYPLAL1.

CONCLUSIONS

High MVPA may attenuate underlying genetic risk for obesity during adolescence, a high-risk period for adult obesity.

Increased Coronary Artery Plaque Volume Among Male Marathon Runners

BACKGROUND

Long-term marathon running improves many cardiovascular risk factors, and is presumed to protect against coronary artery plaque formation. This hypothesis, that long-term marathon running is protective against coronary atherosclerosis, was tested by quantitatively assessing coronary artery plaque using high resolution coronary computed tomographic angiography (CCTA) in veteran marathon runners compared to sedentary control subjects.

METHODS

Men in the study completed at least one marathon yearly for 25 consecutive years. All study subjects underwent CCTA, 12-lead electrocardiogram, measurement of blood pressure, heart rate, and lipid panel. A sedentary matched group was derived from a contemporaneous CCTA database of asymptomatic healthy individuals. CCTAs were analyzed using validated plaque characterization software.

RESULTS

Male marathon runners (n = 50) as compared with sedentary male controls (n = 23) had increased total plaque volume (200 vs. 126 mm3, p < 0.01), calcified plaque volume (84 vs. 44 mm3, p < 0.0001), and non-calcified plaque volume (116 vs. 82 mm3, p = 0.04). Lesion area and length, number of lesions per subject, and diameter stenosis did not reach statistical significance.

CONCLUSION

Long-term male marathon runners may have paradoxically increased coronary artery plaque volume.

Screen time behaviours may interact with obesity genes, independent of physical activity, to influence adolescent BMI in an ethnically diverse cohort

BACKGROUND

There has been little investigation of gene-by-environment interactions related to sedentary behaviour, a risk factor for obesity defined as leisure screen time (ST; i.e. television, video and computer games).

OBJECTIVE

To test the hypothesis that limiting ST use attenuates the genetic predisposition to increased body mass index (BMI), independent of physical activity.

DESIGN

Using 7642 wave II participants of the National Longitudinal Study of Adolescent Health, (Add Health; mean = 16.4 years, 52.6% female), we assessed the interaction of ST (h week(-1) ) and 41 established obesity single nucleotide polymorphisms (SNPs) with age- and sex-specific BMI Z-scores in 4788 European-American (EA), 1612 African-American (AA) and 1242 Hispanic American (HA) adolescents.

RESULTS

Nominally significant SNP*ST interaction were found for FLJ35779 in EA, GNPDA2 in AA and none in HA (EA: beta [SE] = 0.016[0.007]), AA: beta [SE] = 0.016[0.011]) per 7 h week(-1) ST and one risk allele in relation to BMI Z-score.

CONCLUSIONS

While for two established BMI loci, we find evidence that high levels of ST exacerbate the influence of obesity susceptibility variants on body mass; overall, we do not find strong evidence for interactions between the majority of established obesity loci. However, future studies with larger sample sizes, or that may build on our current study and the growing published literature, are clearly warranted.

Acute aortic dissection in blacks: insights from the International Registry of Acute Aortic Dissection

BACKGROUND

Few data exist on race-related differences in acute aortic dissection patients.

METHODS

We evaluated black (n = 189, 14%) or white (n = 1165, 86%) patients (mean age 62.8 ± 15.3 years; 36.4% women) enrolled in 13 US centers participating in the International Registry of Acute Aortic Dissection. We excluded patients of other racial descent.

RESULTS

Type B acute aortic dissection was more frequent in the black cohort (52.4% vs 39.3%, P = .001). Black patients were younger (mean age 54.6 ± 12.8 years vs 64.2 ± 15.2 years, P <.001) and more likely to have a history of cocaine abuse (12% vs 1.6%, P <.001), hypertension (89.7% vs 73.9%, P <.001), and diabetes (13.2% vs 6.4%, P = .001). Conversely, they were less likely to have bicuspid aortic valve (1.8% vs 5.8%, P = .029), iatrogenic dissection (0.5% vs 4.5%, P = .010), and prior aortic dissection repair (7.7% vs 12.8%, P = .047). Presenting features were similar except for more abdominal pain (44.6% vs 30.6%, P <.001) and left ventricular hypertrophy on echocardiogram (44.2% vs 20.1%, P <.001) in blacks. Management was similar. Hypotension/shock/tamponade was less common (7.6% vs 20.1%, P <.001), whereas acute kidney failure was more common (41.0% vs 21.7%, P <.001) in blacks. Mortality was similar in-hospital (14.3% vs 19.1%, P = .110, odds ratio 0.704, 95% confidence interval 0.457-1.085) and at 3 years postdischarge, as evaluated by Kaplan-Meier survival analysis (22.0% vs 14.3%, P = .224, SE = 0.062 and 0.018).

CONCLUSIONS

Our study shows differences in type, etiology, and presentation of blacks and whites with acute aortic dissection, yet similar mortality for these cohorts.

The IRAD classification system for characterizing survival after aortic dissection

BACKGROUND

The classification of aortic dissection into acute (<14 days from symptom onset) versus chronic (≥14 days) is based on survival estimates of patients treated decades before modern diagnostic and treatment modalities were available. A new classification of aortic dissection in the current era may provide clinicians with a more precise method of characterizing the interaction of time, dissection location, and treatment type with survival.

METHODS

We developed separate Kaplan-Meier survival curves for Type A and Type B aortic dissection using data from the International Registry of Aortic Dissection (IRAD). Daily survival was stratified based on type of therapy provided: medical therapy alone (medical), nonsurgical intervention plus medical therapy (endovascular), and open surgery plus medical therapy (surgical). The log-rank statistic was used to compare the survival curves of each management type within Type A and Type B aortic dissection.

RESULTS

There were 1815 patients included, 67.3% male with mean age 62.0 ± 14.2 years. When survival curves were constructed, 4 distinct time periods were noted: hyperacute (symptom onset to 24 hours), acute (2-7 days), subacute (8-30 days), and chronic (>30 days). Overall survival was progressively lower through the 4 time periods.

CONCLUSIONS

This IRAD classification system can provide clinicians with a more robust method of characterizing survival after aortic dissection over time than previous methods. This system will be useful for treating patients, counseling patients and families, and studying new diagnostic and treatment methods.

Abstract 280: Cocaine-Related Aortic Dissection: Lessons from the International Registry of Acute Aortic Dissection

Background: Acute Aortic Dissection (AAD) associated with cocaine use is a rare event for which only limited case reports and small cohort studies are available. This study compares demographics, history, presenting symptoms and in-hospital outcomes among AAD patients with a history of cocaine use (C+) to those of patients without a history of cocaine use (C-) in a large international registry.

Methods: Our study analyzed 3584 patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2012. We divided the population based on documented cocaine use and further stratified patients into Type A (33 C+/2332, 1.4%) and Type B (30 C+/1252, 2.4%) dissection cohorts.

Results: C+ patients presented at a younger age and were more likely to be male and black for both Type A and B dissections. Type B dissection was more common among C+ patients than in C- patients. Cocaine-related AAD was reported more often at US sites compared to European sites (86.4% 51/63 v. 13.6% 8/63, p<0.001). Tobacco use was more prevalent in the C+ cohort. No differences were seen in history of hypertension, known atherosclerosis or time from symptom onset to presentation between cohorts. Type B C+ patients were more likely to be hypertensive at presentation. Both Type A and Type B C+ cohorts had significantly smaller ascending aortic diameters than C- patients. Acute renal failure was more common in Type A C+ patients but mortality was significantly lower in Type A C+ patients vs type C- patients for reasons than could not be identified from the data base.

Conclusions: Cocaine abuse is implicated in approximately 2% of patients with acute aortic dissection. The typical patient is a relatively young male cigarette smoker, who like the majority of patients with AAD, has a history of hypertension. In hospital mortality for cocaine-related Type A dissection is lower than that seen with non-cocaine related type A dissection. The combination of tobacco use, cocaine use, and hypertension may predispose patients to AAD who may otherwise have little risk for the condition.

Abstract 274: Follow-Up of Young Acute Aortic Dissection Patients: How They Differ from Older Patients

Background: Young patients (pts) with acute aortic dissection (AAD) have distinct risk factors and presenting symptoms compared to older pts, but whether these differences extend past discharge is relatively unknown.

Methods: Among pts presenting with AAD enrolled in the International Registry of Acute Aortic Dissection, pts <40 (N=280) were compared with pts ≥ 40 (N=3585). Chi-square analysis or Fischer’s Exact test were performed for categorical variables; age was compared using Student’s T-test. Kaplan-Meier curves were generated for freedom from adverse events rates 0-60 months following discharge. Mean follow-up was 28.6 months.

Results: Significant differences in demographics and history were noted between pts <40 and the older cohort. Young pts more commonly had type A AAD (71.8%, 201/280, v. 64.6%, 2317/ 3585, p<0.016), while type B AAD was more typical in older pts (p<0.016). On imaging studies, pts <40 were less likely to present with IMH (7.3%, 246/3355, v. 2.3%, 6/266, p=0.002), but were more likely to have a patent false lumen (77.9%, 141/181, v. 62.1%, 1425/2295, p<0.001). Surgical management was more common in young pts, for both AAD types. In-hospital complications or mortality did not differ between groups. Kaplan-Meier analysis demonstrated better long-term survival in young pts compared to those ≥ 40 (p=0.029). Kaplan-Meier analyses of freedom from adverse events at 5 years illustrated no difference in aortic growth between groups, but significantly more late interventions in younger pts (p=0.006).

Conclusions: Young pts show distinct differences in comparison to older pts, specifically regarding presentation, AAD type and management. Long-term survival and follow-up intervention rates are higher in young pts.

Acute aortic intramural hematoma: an analysis from the International Registry of Acute Aortic Dissection

BACKGROUND

Acute aortic intramural hematoma (IMH) is an important subgroup of aortic dissection, and controversy surrounds appropriate management.

METHODS AND RESULTS

Patients with acute aortic syndromes in the International Registry of Acute Aortic Dissection (1996-2011) were evaluated to examine differences between patients (based on the initial imaging test) with IMH or classic dissection (AD). Of 2830 patients, 178 had IMH (64 type A [42%], 90 type B [58%], and 24 arch). Patients with IMH were older and presented with similar symptoms, such as severe pain. Patients with type A IMH were less likely to present with aortic regurgitation or pulse deficits and were more likely to have periaortic hematoma and pericardial effusion. Although type A IMH and AD were managed medically infrequently, type B IMH were more frequently treated medically. Overall in-hospital mortality was not statistically different for type A IMH compared to AD (26.6% versus 26.5%; P=0.998); type A IMH managed medically had significant mortality (40.0%), although less than classic AD (61.8%; P=0.195). Patients with type B IMH had a hospital mortality that was less but did not differ significantly (4.4% versus 11.1%; P=0.062) from classic AD. One-year mortality was not significantly different between AD and IMH.

CONCLUSIONS

Acute IMH has similar presentation to classic AD but is more frequently complicated with pericardial effusions and periaortic hematoma. Patients with IMH have a mortality that does not differ statistically from those with classic AD. A small subgroup of type A IMH patients are managed medically and have a significant in-hospital mortality.

Sickle cell trait associated with sudden death in competitive athletes

Sickle cell trait (SCT; hemoglobin AS) occurs in 8% of African Americans and although typically benign has been associated with sudden death in military recruits during intense physical activity. However, the role of SCT in the deaths of trained athletes is less well documented or acknowledged. The 31-year United States Sudden Death in Athletes Registry was interrogated to determine the frequency, epidemiology, and clinical profile of SCT-related death in a large population of competitive athletes. Of 2,462 athlete deaths, 23 (0.9% overall, 3.3% of African Americans) occurred in association with SCT: ages 12 to 22 years, 21 male (91%), and all African Americans. SCT diagnosis was made by solubility testing (n = 13) and/or hemoglobin electrophoresis (n = 16). Most victims competed in college (n = 17) and in football (n = 19). Of 271 African American football deaths in the registry, 7% (1 in 14) were known to be associated with SCT. Each athlete experienced distinctive noninstantaneous collapse with gradual deterioration over several minutes associated with vigorous or exhaustive physical exertion, usually during conditioning drills (n = 22) and typically early in the training season. Ambient temperatures were ≥80°F in 20 patients (87%), with most events in southern or border states during the summer and autumn (n = 17 [74%]). In conclusion, SCT can be associated with largely unpredictable sudden collapse and death and apparent predilection for African American college football players during conditioning. Understanding the risks, mechanisms, and event triggers of SCT may allow lifesaving alterations in training methods to be implemented.

Estimation of genetic effects on BMI during adolescence in an ethnically diverse cohort: The National Longitudinal Study of Adolescent Health

OBJECTIVE

The contribution of genetic variants to body mass index (BMI) during adolescence across multiethnic samples is largely unknown. We selected genetic loci associated with BMI or obesity in European-descent samples and examined them in a multiethnic adolescent sample.

DESIGN AND SAMPLE

In 5103 European American (EA), 1748 African American (AfA), 1304 Hispanic American (HA) and 439 Asian American (AsA) participants of the National Longitudinal Study of Adolescent Health (Add Health; ages 12-21 years, 47.5% male), we assessed the association between 41 established obesity-related single-nucleotide polymorphisms (SNPs) with BMI using additive genetic models, stratified by race/ethnicity, and in a pooled meta-analysis sample. We also compared the magnitude of effect for BMI-SNP associations in EA and AfA adolescents to comparable effect estimates from 11 861 EA and AfA adults in the Atherosclerosis Risk in Communities study (ages 45-64 years, 43.2% male).

RESULTS

Thirty-five of 41 BMI-SNP associations were directionally consistent with published studies in European populations, 18 achieved nominal significance (P<0.05; effect sizes from 0.19 to 0.71 kg m(-2) increase in BMI per effect allele), while 4 (FTO, TMEM18, TFAP2B, MC4R) remained significant after Bonferroni correction (P<0.0015). Of 41 BMI-SNP associations in AfA, HA and AsA adolescents, nine, three and five, respectively, were directionally consistent and nominally significant. In the pooled meta-analysis, 36 of 41 effect estimates were directionally consistent and 21 of 36 were nominally significant. In EA adolescents, BMI effect estimates were larger (P<0.05) for variants near TMEM18, PTER and MC4R and smaller for variants near MTIF3 and NRXN3 compared with EA adults.

CONCLUSION

Our findings suggest that obesity susceptibility loci may have a comparatively stronger role during adolescence than during adulthood, with variation across race/ethnic subpopulation.

Pharmacotherapy in the treatment of mitral regurgitation: a systematic review

BACKGROUND AND AIM OF THE STUDY

Chronic mitral regurgitation (MR) causes volume overload on the left ventricle and, if uncorrected, will over time lead to left ventricular remodeling and heart failure. The benefits of angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) in primary MR are not well defined.

METHODS

MEDLINE was searched for studies in which the effects of ACE inhibitors and ARBs on chronic MR had been examined. The inclusion criteria required the patient population to have chronic MR, a normal left ventricular ejection fraction, and to report a quantitative measure of the change in MR severity. Studies in which patients had secondary MR were excluded.

RESULTS

Nineteen studies met the inclusion criteria (13 daily therapy, five single-dose, and one combined study). The pooled mean decrease in regurgitant fraction (RF) was 7.7% [95% CI 4.9, 10.6] and 9.3% [95% CI 3.4, 15.2] for studies in patients with daily therapy and single-dose therapy, respectively. Among studies which reported changes in regurgitant volume (RV), the pooled mean decrease was 7.9 ml [95% CI 1.4, 14.5]. For patients with mitral valve prolapse (MVP), the pooled mean reduction in RF was 8.1% [95% CI 4.3, 11.9] and in rheumatic disease it was 3.4% [95% CI 13.2 - 7.0]. Across the seven studies of daily therapy which reported a change in left ventricular end-diastolic volume index (LVEDVI), the mean decrease was 11.5 ml/m2 [95% CI 2.4, 20.6].

CONCLUSION

ACE inhibitors and ARBs each reduced the RF, RV, and left ventricular size by a modest degree in chronic primary MR.

Type-selective benefits of medications in treatment of acute aortic dissection (from the International Registry of Acute Aortic Dissection [IRAD])

The effects of medications on the outcome of aortic dissection remain poorly understood. We sought to address this by analyzing the International Registry of Acute Aortic Dissection (IRAD) global registry database. A total of 1,301 patients with acute aortic dissection (722 with type A and 579 with type B) with information on their medications at discharge and followed for ≤5 years were analyzed for the effects of the medications on mortality. The initial univariate analysis showed that use of β blockers was associated with improved survival in all patients (p = 0.03), in patients with type A overall (p = 0.02), and in patients with type A who received surgery (p = 0.006). The analysis also showed that use of calcium channel blockers was associated with improved survival in patients with type B overall (p = 0.02) and in patients with type B receiving medical management (p = 0.03). Multivariate models also showed that the use of β blockers was associated with improved survival in those with type A undergoing surgery (odds ratio 0.47, 95% confidence interval 0.25 to 0.90, p = 0.02) and the use of calcium channel blockers was associated with improved survival in patients with type B medically treated patients (odds ratio 0.55, 95% confidence interval 0.35 to 0.88, p = 0.01). In conclusion, the present study showed that use of β blockers was associated with improved outcome in all patients and in type A patients (overall as well as in those managed surgically). In contrast, use of calcium channel blockers was associated with improved survival selectively in those with type B (overall and in those treated medically). The use of angiotensin-converting enzyme inhibitors did not show association with mortality.

Sensitivity of the aortic dissection detection risk score, a novel guideline-based tool for identification of acute aortic dissection at initial presentation: results from the international registry of acute aortic dissection

BACKGROUND

In 2010, the American Heart Association and American College of Cardiology released guidelines for the diagnosis and management of patients with thoracic aortic disease, which identified high-risk clinical features to assist in the early detection of acute aortic dissection. The sensitivity of these risk markers has not been validated.

METHODS AND RESULTS

We examined patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2009. The number of patients with confirmed acute aortic dissection who presented with 1 or more of 12 proposed clinical risk markers was determined. An aortic dissection detection (ADD) risk score of 0 to 3 was calculated on the basis of the number of risk categories (high-risk predisposing conditions, high-risk pain features, high-risk examination features) in which patients met criteria. The ADD risk score was tested for sensitivity. Of 2538 patients with acute aortic dissection, 2430 (95.7%) were identified by 1 or more of 12 proposed clinical risk markers. With the use of the ADD risk score, 108 patients (4.3%) were identified as low risk (ADD score 0), 927 patients (36.5%) were intermediate risk (ADD score 1), and 1503 patients (59.2%) were high risk (ADD score 2 or 3). Among 108 patients with no clinical risk markers present (ADD score 0), 72 had chest x-rays recorded, of which 35 (48.6%) demonstrated a widened mediastinum.

CONCLUSIONS

The clinical risk markers proposed in the 2010 thoracic aortic disease guidelines and their application as part of the ADD risk score comprise a highly sensitive clinical tool for the detection of acute aortic dissection.