Twenty-five years of observations from the International Registry of Acute Aortic Dissection (IRAD) and its impact on the cardiovascular scientific community

OBJECTIVE

The International Registry of Acute Aortic Dissection (IRAD) celebrated its 25th anniversary in January 2021. This study evaluated IRAD's role in promoting the understanding and management of acute aortic dissection (AD) over these years.

METHODS

IRAD studies were identified, analyzed, and ranked according to their citations per year (c/y) to determine the most-cited IRAD studies and topics. A systematic search of the literature identified cardiovascular guidelines on the diagnosis and management of acute AD. Consequently, IRAD's presence and impact were quantified using these documents.

RESULTS

Ninety-seven IRAD studies were identified, of which 82 obtained more than 10 cumulative citations. The median c/y index was 7.33 (25th-75th percentile, 4.01-16.65). Forty-two studies had a greater than median c/y index and were considered most impactful. Of these studies, most investigated both type A and type B AD (n = 17, 40.5%) and short-term outcomes (n = 26, 61.9%). Nineteen guideline documents were identified from 26 cardiovascular societies located in Northern America, Europe, and Japan. Sixty-nine IRAD studies were cited by these guidelines, including 38 of the 42 most-impactful IRAD studies. Among them, partial thrombosis of the false lumen as a predictor of postdischarge mortality and aortic diameters as a predictor of type A occurrence were determined as most-impactful specific IRAD topics by their c/y index.

CONCLUSIONS

IRAD has had and continues to have an important role in providing observations, credible knowledge, and research questions to improve the outcomes of patients with acute AD.

The ZFP36 family of RNA binding proteins regulates homeostatic and autoreactive T cell responses

RNA binding proteins are important regulators of T cell activation, proliferation, and cytokine production. The zinc finger protein 36 (ZFP36) family genes (Zfp36, Zfp36l1, and Zfp36l2) encode RNA binding proteins that promote the degradation of transcripts containing AU-rich elements. Numerous studies have demonstrated both individual and shared functions of the ZFP36 family in immune cells, but their collective function in T cells remains unclear. Here, we found a redundant and critical role for the ZFP36 proteins in regulating T cell quiescence. T cell-specific deletion of all three ZFP36 family members in mice resulted in early lethality, immune cell activation, and multiorgan pathology characterized by inflammation of the eyes, central nervous system, kidneys, and liver. Mice with T cell-specific deletion of any two Zfp36 genes were protected from this spontaneous syndrome. Triply deficient T cells overproduced proinflammatory cytokines, including IFN-γ, TNF, and GM-CSF, due to increased mRNA stability of these transcripts. Unexpectedly, T cell-specific deletion of both Zfp36l1 and Zfp36l2 rendered mice resistant to experimental autoimmune encephalomyelitits due to failed priming of antigen-specific CD4⁺ T cells. ZFP36L1 and ZFP36L2 double-deficient CD4⁺ T cells had poor proliferation during in vitro T helper cell polarization. Thus, the ZFP36 family redundantly regulates T cell quiescence at homeostasis, but ZFP36L1 and ZFP36L2 are specifically required for antigen-specific T cell clonal expansion.

Early Mortality in Type A Acute Aortic Dissection: Insights From the International Registry of Acute Aortic Dissection

Importance

Early data revealed a mortality rate of 1% to 2% per hour for type A acute aortic dissection (TAAAD) during the initial 48 hours. Despite advances in diagnostic testing and treatment, this mortality rate continues to be cited because of a lack of contemporary data characterizing early mortality and the effect of timely surgery.

Objective

To examine early mortality rates for patients with TAAAD in the contemporary era.

Design, Setting, and Participants

This cohort study examined data for patients with TAAAD in the International Registry of Acute Aortic Dissection between 1996 and 2018. Patients were grouped according to the mode of their intended treatment, surgical or medical.

Exposure

Surgical treatment.

Main Outcomes and Measures

Mortality was assessed in the initial 48 hours after hospital arrival using Kaplan-Meier curves. In-hospital complications were also evaluated.

Results

A total of 5611 patients with TAAAD were identified based on intended treatment: 5131 (91.4%) in the surgical group (3442 [67.1%] male; mean [SD] age, 60.4 [14.1] years) and 480 (8.6%) in the medical group (480 [52.5%] male; mean [SD] age, 70.9 [14.7] years). Reasons for medical management included advanced age (n = 141), comorbidities (n = 281), and patient preference (n = 81). Over the first 48 hours, the mortality for all patients in the study was 5.8%. Among patients who were medically managed, mortality was 0.5% per hour (23.7% at 48 hours). For those whose intended treatment was surgical, 48-hour mortality was 4.4%. In the surgical group, 51 patients (1%) died before the operation.

Conclusions and Relevance

In this study, the overall mortality rate for TAAAD was 5.8% at 48 hours. For patients in the medical group, TAAAD had a mortality rate of 0.5% per hour (23.7% at 48 hours). However, among those in the surgical group, 48-hour mortality decreased to 4.4%.

Involvement of TLR2-TLR4, NLRP3, and IL-17 in pain induced by a novel Sprague-Dawley rat model of experimental autoimmune encephalomyelitis

Up to 92% of patients suffering from multiple sclerosis (MS) experience pain, most without adequate treatment, and many report pain long before motor symptoms associated with MS diagnosis. In the most commonly studied rodent model of MS, experimental autoimmune encephalomyelitis (EAE), motor impairments/disabilities caused by EAE can interfere with pain testing. In this study, we characterize a novel low-dose myelin-oligodendrocyte-glycoprotein (MOG)-induced Sprague-Dawley (SD) model of EAE-related pain in male rats, optimized to minimize motor impairments/disabilities. Adult male SD rats were treated with increasing doses of intradermal myelin-oligodendrocyte-glycoprotein (MOG1-125) (0, 4, 8, and 16 μg) in incomplete Freund's adjuvant (IFA) vehicle to induce mild EAE. Von Frey testing and motor assessments were conducted prior to EAE induction and then weekly thereafter to assess EAE-induced pain and motor impairment. Results from these studies demonstrated that doses of 8 and 16 μg MOG1-125 were sufficient to produce stable mechanical allodynia for up to 1 month in the absence of hindpaw motor impairments/disabilities. In the follow-up studies, these doses of MOG1-125, were administered to create allodynia in the absence of confounded motor impairments. Then, 2 weeks later, rats began daily subcutaneous injections of the Toll-like receptor 2 and 4 (TLR2-TLR4) antagonist (+)-naltrexone [(+)-NTX] or saline for an additional 13 days. We found that (+)-NTX also reverses EAE-induced mechanical allodynia in the MOG-induced SD rat model of EAE, supporting parallels between models, but now allowing a protracted timecourse to be examined completely free of motor confounds. Exploring further mechanisms, we demonstrated that both spinal NOD-like receptor protein 3 (NLRP3) and interleukin-17 (IL-17) are necessary for EAE-induced pain, as intrathecal injections of NLRP3 antagonist MCC950 and IL-17 neutralizing antibody both acutely reversed EAE-induced pain. Finally, we show that spinal glial immunoreactivity induced by EAE is reversed by (+)-NTX, and that spinal demyelination correlates with the severity of motor impairments/disabilities. These findings characterize an optimized MOG-induced SD rat model of EAE for the study of pain with minimal motor impairments/disabilities. Finally, these studies support the role of TLR2-TLR4 antagonists as a potential treatment for MS-related pain and other pain and inflammatory-related disorders.

Alcohol Septal Ablation for Obstructive Hypertrophic Cardiomyopathy

Over the past several decades, alcohol septal ablation has become an established therapy for selected patients, in whom there is clinical improvement in symptoms as well as objective functional capacity. Patient selection is essential to success, with continued emphasis on the procedure being performed by experienced operators as part of a multidisciplinary team. In many patients, the outcomes of alcohol septal ablation are comparable to the standard of surgical myectomy. The optimization of the outcomes of alcohol septal ablation is essential for the longitudinal care of patients with hypertrophic cardiomyopathy.

Location of Aortic Enlargement and Risk of Type A Dissection at Smaller Diameters

BACKGROUND

Previous work has demonstrated that more than one-half of acute type A aortic dissections (ATADs) occur at a maximal aortic diameter (MAD) of <5.5 cm. However, no analysis has investigated whether ATAD risk at smaller MADs is more common with modest dilation of the aortic root (AR) or supracoronary ascending aorta (AA) in patients without genetically triggered aortopathy.

OBJECTIVES

This study sought to determine if the segment of modest aortic dilation affects risk of ATAD.

METHODS

Using the International Registry of Acute Aortic Dissection (IRAD) database from May 1996 to October 2016, we identified 667 ATAD patients with MAD <5.5 cm. Patients were stratified by location of the largest proximal aortic segment (AR or AA). Patients with known genetically triggered aortopathy were excluded. MADs at time of dissection were compared between AR and AA groups. Secondary outcomes included operation, postoperative outcomes, and long-term survival.

RESULTS

Of patients with ATAD at an MAD <5.5 cm, 79.5% (n = 530) were in the AA group and 20.5% (n = 137) in the AR group. Modestly dilated ARs (median MAD 4.6 cm [IQR: 4.1-5.0 cm]) dissected at a significantly smaller diameter than modestly dilated AAs (median MAD 4.8 cm [IQR: 4.4-5.1 cm]) (P < 0.01). AR patients were significantly younger than AA patients (58.5 ± 13.0 years vs 63.2 ± 13.3 years; P < 0.01) and more commonly male (78% vs 65%; P < 0.01). Postoperative and long-term outcomes did not differ between groups.

CONCLUSIONS

ATAD appears to occur at smaller diameters in patients with modest dilation in the AR vs the AA (4.6 vs 4.8 cm). These findings may have implications for future consensus guidelines regarding the management of patients with aortic disease.

Iatrogenic aortic dissection of the descending aorta after percutaneous coronary intervention

Aortic dissection is a rare and potentially fatal complication of coronary angiography. We report a case of a woman in her late 80s who underwent a left femoral approach coronary angiogram for evaluation of a transcatheter aortic valve replacement (TAVR). Following the procedure, she had a cardiac arrest and was found to have a descending aortic dissection on transoesophageal echocardiogram. Autopsy showed an acute intimal tear of the descending aorta, most likely related to catheter manipulation. Patients undergoing evaluation for TAVR, who tend to be elderly with concomitant atherosclerosis, are at risk for complications following cardiac catheterisation including aortic dissection.

Aortic Size and Clinical Care Pathways Before Type A Aortic Dissection

Patients with aortic enlargement are recommended to undergo serial imaging and clinical follow-up until they reach surgical thresholds. This study aimed to identify aortic diameter and care of patients with aortic imaging before aortic dissection (AD). In a retrospective cohort of AD patients, we evaluated previous imaging results in addition to ordering providers and indications. Imaging was stratified as >1 or <1 year: 62 patients (53% men) had aortic imaging before AD (most recent test: 82% echo, 11% computed tomography, 6% magnetic resonance imaging). Imaging was ordered most frequently by primary care physicians (35%) and cardiologists (39%). The most frequent imaging indications were arrhythmia (11%), dyspnea (10%), before or after aortic valve surgery (8%), chest pain (6%), and aneurysm surveillance in 13%. Of all patients, 94% had aortic diameters below the surgical threshold before the AD. Imaging was performed <1 year before AD in 47% and aortic size was 4.4 ± 0.8 cm in ascending aorta and 4.0 ± 0.8 cm in sinus. In patients whose most recent imaging was >1 year before AD (1,317 ± 1,017 days), the mean ascending aortic diameter was 4.2 ± 0.4 cm. In conclusion, in a series of patients with aortic imaging before AD, the aortic size was far short of surgical thresholds in 94% of the group. In >50%, imaging was last performed >1 year before dissection.

T cell transgressions: Tales of T cell form and function in diverse disease states

Insights into T cell form, function, and dysfunction are rapidly evolving. T cells have remarkably varied effector functions including protecting the host from infection, activating cells of the innate immune system, releasing cytokines and chemokines, and heavily contributing to immunological memory. Under healthy conditions, T cells orchestrate a finely tuned attack on invading pathogens while minimizing damage to the host. The dark side of T cells is that they also exhibit autoreactivity and inflict harm to host cells, creating autoimmunity. The mechanisms of T cell autoreactivity are complex and dynamic. Emerging research is elucidating the mechanisms leading T cells to become autoreactive and how such responses cause or contribute to diverse disease states, both peripherally and within the central nervous system. This review provides foundational information on T cell development, differentiation, and functions. Key T cell subtypes, cytokines that create their effector roles, and sex differences are highlighted. Pathological T cell contributions to diverse peripheral and central disease states, arising from errors in reactivity, are highlighted, with a focus on multiple sclerosis, rheumatoid arthritis, osteoarthritis, neuropathic pain, and type 1 diabetes.

Acute Myocardial Infarction-Like Events in Related Patients With a Desmoplakin-Associated Arrhythmogenic Cardiomyopathy

Patients with familial arrhythmogenic cardiomyopathy typically present with ventricular arrhythmias or progressive heart failure. This paper characterizes a rare presentation of an underlying genetic cardiomyopathy with clinical manifestations mimicking an acute myocardial infarction in 2 siblings, each with the same mutation in the desmoplakin (DSP) gene. (Level of Difficulty: Advanced.)

Impact of a multidisciplinary acute aortic dissection program: Improved outcomes with a comprehensive initial surgical repair strategy

OBJECTIVE

As part of a multidisciplinary aortic dissection (AD) program, a more comprehensive repair strategy for patients with acute type A aortic dissection (ATAAD) and frequent endografting for suitable patients with type B aortic dissection (ATBAD) was adopted in 2015. The aim of this study was to evaluate the impact of these changes.

METHODS

This study is a retrospective review of a prospective database containing all patients treated for acute AD between 2003 and 2020. Patients were grouped based on differing repair strategies (pre 2015 vs post 2015). Clinical characteristics, procedural details, and survival data were analyzed.

RESULTS

During this time, 323 patients (210 pre, 113 post) were treated for acute AD at our institution. There were 221 patients with ATAAD (149 pre, 72 post) and 102 patients with ATBAD (61 pre, 41 post). The majority (60%) were males, with a mean age of 65.9 ± 15.2 years. There were no differences in cardiovascular risk factors or demographics between the groups. After 2015, fewer patients with ATAAD underwent medical management alone (15% pre vs 4% post; P = .014), and most that underwent surgical intervention had a total arch or aggressive hemiarch repair (27% pre vs 78% post; P < .001). Seventy-four patients (73%) with ATBAD were treated medically, whereas 28 underwent medical management and endografting (23% pre, 34% post; P = .214). For all patients with AD, 30-day mortality was significantly improved (26% pre vs 10% post; P < .001) especially among patients who underwent ATAAD surgery (23% pre vs 9% post; P = .018). Three-year Kaplan-Meier survival estimates showed survival improvement among patients with ATAAD (Log rank P-value = .019); however, this improvement does not extend to type B dissections or the overall cohort. A survival analysis landmarked to 30 days after initial presentation showed no statistical difference in survival from 30 days to 3 years post-presentation.

CONCLUSIONS

A more comprehensive repair strategy in the management of patients with acute AD resulted in improved overall patient outcomes and significantly decreased 30-day mortality, even though more complex repairs were performed. The long-term impact of the changes made to our program remains to be evaluated.

Type A Acute Aortic Dissection Presenting With Cerebrovascular Accident at Advanced Age

Our aim was to analyze outcomes of patients aged 70 years or above presenting with type A acute aortic dissection (TAAAD) and cerebrovascular accident (CVA). A retrospective analysis of the International Registry of Acute Aortic Dissection (IRAD) was conducted. Patients aged 70 years or above (n = 1449) were stratified according to presence or absence of CVA before surgery (CVA: n = 110, 7.6%). In-hospital outcomes and mortality up to 5 years were analyzed. Additionally, in-hospital outcomes of patients who received medical management were described. No patient presenting with CVA over the age of 87 years underwent surgery. The rates of in-hospital mortality and post-operative CVA were significantly higher in patients presenting with CVA (in-hospital mortality: 32.7% vs 21.7%, P = 0.008; post-operative CVA: 23.4% vs 8.3%, P < 0.001). Presence of CVA was independently associated with significantly increased in-hospital mortality (odds ratio 2.99, 95% confidence interval 1.35 - 6.60, P = 0.007). In survivors of the hospital stay, presenting CVA had no independent influence on mortality up to 5 years (hazard ratio 1.52, 95% confidence interval 0.99 - 2.31, P = 0.54). In medically managed patients, exceedingly high rates of in-hospital mortality (71.4%) and CVA (90.9%) were noted. Patients presenting with TAAAD and CVA at ≥ 70 years of age are at significantly increased risk of in-hospital mortality, although long-term mortality is not affected in hospital survivors. Medical management is associated with poor outcomes. We believe that surgical management should be offered after critical assessment of comorbidities.

Sudden Unexpected Death Due to Myocarditis in Young People, Including Athletes

Sudden deaths in young active people and athletes are distinctly uncommon and frequently related to highly visible cardiovascular conditions including hypertrophic cardiomyopathy and congenital coronary anomalies. Myocarditis is also a cause of sudden death in the young, but frequently under-recognized clinically, and therefore deserving of the present analysis. Two large registries were interrogated for cases of myocarditis, and clinical, demographic, and pathologic findings were assessed. Of 97 cases of myocarditis identified, ages were 19.3 ± 6.2 years, 76% male, and 58 were physically active at or near the time of death. Almost one-half of the 97 cases (47%) had a viral prodrome or symptoms (i.e., syncope, malaise, chest pain or palpitations). Nine were evaluated by cardiologists, but in none was a diagnosis of myocarditis established before death. The inflammatory cellular infiltrate was predominantly lymphocytic (67%), was most frequently multifocal (59%) and involved the conduction system (including atrioventricular node), 38%. In conclusion, myocarditis is an important but under-recognized cause of sudden death in young people including competitive athletes. Clinical diagnosis is difficult because symptoms are nonspecific and often ignored, requiring high index of suspicion for diagnosis. Our data support the ACC/AHA consensus guidelines recommending removal of individuals with myocarditis from competitive sports during recovery. Selective examination of conduction systems showed a number of cases with involvement of myocarditis, suggesting a novel mechanism for sudden death.

Toll-like receptor 2 and 4 antagonism for the treatment of experimental autoimmune encephalomyelitis (EAE)-related pain

Neuropathic pain is a major symptom of multiple sclerosis (MS) with up to 92% of patients reporting bodily pain, and 85% reporting pain severe enough to cause functional disability. None of the available therapeutics target MS pain. Toll-like receptors 2 and 4 (TLR2/TLR4) have emerged as targets for treating a wide array of autoimmune disorders, including MS, as well as having demonstrated success at suppressing pain in diverse animal models. The current series of studies tested systemic TLR2/TLR4 antagonists in males and females in a low-dose Myelin oligodendrocyte glycoprotein (MOG) experimental autoimmune encephalomyelitis (EAE) model, with reduced motor dysfunction to allow unconfounded testing of allodynia through 50+ days post-MOG. The data demonstrated that blocking TLR2/TLR4 suppressed EAE-related pain, equally in males and females; upregulation of dorsal spinal cord proinflammatory gene expression for TLR2, TLR4, NLRP3, interleukin-1β, IkBα, TNF-α and interleukin-17; and upregulation of dorsal spinal cord expression of glial immunoreactivity markers. In support of these results, intrathecal interleukin-1 receptor antagonist reversed EAE-induced allodynia, both early and late after EAE induction. In contrast, blocking TLR2/TLR4 did not suppress EAE-induced motor disturbances induced by a higher MOG dose. These data suggest that blocking TLR2/TLR4 prevents the production of proinflammatory factors involved in low dose EAE pathology. Moreover, in this EAE model, TLR2/TLR4 antagonists were highly effective in reducing pain, whereas motor impairment, as seen in high dose MOG EAE, is not affected.

Clinical Features and Outcomes of Pregnancy-Related Acute Aortic Dissection

Importance

Women with aortopathy conditions are at risk for pregnancy-related aortic dissection, and these conditions may not be recognized until after the aortic dissection occurs.

Objective

To examine the clinical characteristics, imaging features, and outcomes in women with pregnancy-related acute aortic dissection.

Design, Setting, and Participants

A cohort study, comprising data from the International Registry of Acute Aortic Dissection (IRAD) (February 1, 1998, to February 28, 2018). The multicenter referral center study included 29 women with aortic dissection during pregnancy or less than 12 weeks post partum in IRAD from 1998 to 2018.

Main Outcomes and Measures

Clinical features of pregnancy-related aortic dissection to be studied included underlying aortopathy, aortic size, type of aortic dissection, timing of dissection, hypertension, and previous aortic surgery.

Results

A total of 29 women (mean [SD] age, 32 [6] years) had pregnancy-related aortic dissection, representing 0.3% of all aortic dissections and 1% of aortic dissection in women in the IRAD. Among women younger than 35 years, aortic dissection was related to pregnancy in 20 of 105 women (19%). Thirteen women (45%) had type A aortic dissection, and 16 women (55%) had type B. Aortic dissection onset was known in 27 women (93%): 15 during pregnancy, 4 in the first trimester, and 11 in the third trimester; 12 were post partum, occurring a mean (SD) of 12.5 (14) days post partum. At type A aortic dissection diagnosis, the mean (SD) aortic diameters were sinus of Valsalva, 54.5 (5) mm and ascending aorta, 54.7 (6) mm. At type B aortic dissection diagnosis, the mean (SD) descending aortic diameter was 32.5 (5) mm. Twenty women (69%) had an aortopathy condition or a positive family history: 13 women (65%) with Marfan syndrome, 2 women (10%) with Loeys-Dietz syndrome, 2 women (10%) with bicuspid aortic valves, 2 women (10%) with a family history of aortic disease, and 1 woman (5%) with familial thoracic aortic aneurysm. Aortopathy was not recognized until after aortic dissection in 47% of the women. Twenty-eight women (97%) survived aortic dissection hospitalization.

Conclusions and Relevance

Aortic dissection complicating pregnancy is rare. Most pregnancy-related aortic dissection is due to an aortopathy often not diagnosed until after aortic dissection. In this study, type A aortic dissections were associated with a dilated aorta, and type B aortic dissections often were not. Recognition of underlying conditions and risks for aortic dissection may improve management of pregnancy in women with aortopathy.

Experimental autoimmune encephalopathy (EAE)-induced hippocampal neuroinflammation and memory deficits are prevented with the non-opioid TLR2/TLR4 antagonist (+)-naltrexone

Multiple sclerosis (MS) is associated with burdensome memory impairments and preclinical literature suggests that these impairments are linked to neuroinflammation. Previously, we have shown that toll-like receptor 4 (TLR4) antagonists, such as (+)-naltrexone [(+)-NTX], block neuropathic pain and associated spinal inflammation in rats. Here we extend these findings to first demonstrate that (+)-NTX blocks TLR2 in addition to TLR4. Additionally, we examined in two rat strains whether (+)-NTX could attenuate learning and memory disturbances and associated neuroinflammation using a low-dose experimental autoimmune encephalomyelitis (EAE) model of MS. EAE is the most commonly used experimental model for the human inflammatory demyelinating disease, MS. This low-dose model avoided motor impairments that would confound learning and memory measurements. Fourteen days later, daily subcutaneous (+)-NTX or saline injections began and continued throughout the study. Contextual and auditory-fear conditioning were conducted at day 21 to assess hippocampal and amygdalar function. With this low-dose model, EAE impaired long-term, but not short-term, contextual fear memory; both long-term and short-term auditory-cued fear memory were spared. This was associated with increased mRNA for hippocampal interleukin-1β (IL-1β), TLR2, TLR4, NLRP3, and IL-17 and elevated expression of the microglial marker Iba1 in CA1 and DG regions of the hippocampus, confirming the neuroinflammation observed in higher-dose EAE models. Importantly, (+)-NTX completely prevented the EAE-induced memory impairments and robustly attenuated the associated proinflammatory effects. These findings suggest that (+)-NTX may exert therapeutic effects on memory function by dampening the neuroinflammatory response in the hippocampus through blockade of TLR2/TLR4. This study suggests that TLR2 and TLR4 antagonists may be effective at treating MS-related memory deficits.

Transesophageal Echocardiography to Diagnose Watchman Device Infection

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The authors report a rare case of infected Watchman device 4 months after placement.

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A high index of suspicion allowed timely diagnosis of Watchman device infection.

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Transesophageal echocardiography led to diagnosis of an infected Watchman device.

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High clinical morbidity is associated with Watchman device endocarditis.

The Clinical Impact of Imaging Surveillance and Clinic Visit Frequency after Acute Aortic Dissection

Background  Guidelines recommend frequent follow-up after acute aortic dissection (AAD), but optimal rates of follow-up are not clear.

Methods  We examined rates of imaging and clinic visits in 267 individuals surviving AAD during recommended intervals (≤1, > 1–3, > 3–6, > 6–12 months, then annually), frequency of adverse imaging findings, and the relationship between follow-up and mortality.

Results  Type A and B AAD were noted in 46 and 54% of patients, respectively. Mean follow-up was 54.7 ± 13.3 months, with 52 deaths. Adverse imaging findings peaked at 6 to 12 months (5.6%), but rarely resulted in an intervention (3.4% peak at 6–12 months). Compared with those with less frequent imaging, patients with imaging for 33 to 66% of intervals ( p  = 0.22) or ≥66% of intervals ( p  = 0.77) had similar adjusted survival. In comparison to patients with fewer clinic visits, those with visits in 33 to 66% of intervals experienced lower adjusted mortality (hazards ratio: 0.47, 95% confidence interval: 0.23–0.97, p  = 0.04), with no difference seen in those with ≥66% (vs. < 33%) interval visits ( p  = 0.47). Imaging at 6 to 12 months (vs. none) was associated with decreased adjusted mortality (hazards ratio: 0.50, 95% confidence interval: 0.27–0.91, p  = 0.02), while imaging during other intervals, or clinic visits during any specific intervals, was not associated with a difference in mortality ( p  > 0.05 for each).

Conclusions  Adverse imaging findings following AAD are common, but rarely require prompt intervention. Patients with the lowest and highest rates of clinic visits experienced increased mortality. While the overall rate of surveillance imaging did not correlate with mortality, adverse imaging findings and related interventions peaked at 6 to 12 months after AAD, and imaging during this time was associated with improved survival.

Association of Guideline Adherence for Serial Evaluations With Survival and Adverse Clinical Events in Patients With Asymptomatic Severe Aortic Stenosis

Importance

For patients with asymptomatic severe aortic stenosis and normal left ventricular function, current practice guidelines empirically recommend serial evaluations every 6 to 12 months. The benefit of this clinical monitoring is unknown.

Objective

To determine the association of guideline adherence with clinical outcomes in patients with asymptomatic severe aortic stenosis.

Design, Setting, and Participants

This retrospective cohort study involved 300 patients with asymptomatic severe aortic stenosis who were seen in the ambulatory Minneapolis Heart Institute at Abbott Northwestern Hospital. Rates of survival and adverse clinical events, including myocardial infarction, stroke, and heart failure hospitalization, were compared between patients who adhered to serial evaluation guidance and those who did not. Medical records were reviewed from July 25, 2007, to December 6, 2012. Data analysis took place from February 4, 2017, to July 10, 2017.

Main Outcomes and Measures

All-cause mortality, heart failure hospitalization, and major adverse clinical events during follow-up.

Results

The study population of 300 comprised 143 men (47.7%) and had a mean (SD) age of 78.6 (11.5) years. There were no differences in age, race/ethnicity, sex, comorbidities, insurance status, left ventricular function, and aortic stenosis severity between patients with (n = 202) and patients without (n = 98) guideline adherence. Aortic valve replacement (surgical or catheter based) was performed more frequently (54.0% vs 19.4%; P < .001) and the median (interquartile range) time for this performance was earlier (2.2 [1.2-3.6] years vs 3.5 [2.0-5.8] years; P < .001) in patients with guideline adherence. All-cause mortality was higher for nonadherent patients (hazard ratio [HR], 1.57; 95% CI, 1.07-2.30; P < .001), and these patients also had a higher rate of hospital admission for heart failure decompensation in follow-up (HR, 1.66; 95% CI, 1.27-2.18; P < .001). Four-year survival that is free from death and heart failure hospitalization was higher for adherent patients than for nonadherent patients (38.7% vs 23.3%; P < .001), and this difference remained significant in models adjusted for baseline variables (adjusted HR, 1.54; 95% CI, 1.04-2.29; P = .03).

Conclusions and Relevance

The findings of this study support the need for close monitoring of patients with asymptomatic severe aortic stenosis and help to validate current guidelines for serial evaluations. These findings also support initiatives to improve guideline adherence in clinical practice.

Insights From the International Registry of Acute Aortic Dissection: A 20-Year Experience of Collaborative Clinical Research

Acute aortic dissection (AAD) is a life-threatening condition associated with high morbidity and mortality rates, and it remains a challenge to diagnose and treat. The International Registry of Acute Aortic Dissection was established in 1996 with the mission to raise awareness of this condition and provide insights to guide diagnosis and treatment. Since then, >7300 cases have been included from >51 sites in 12 countries. Although presenting symptoms and physical findings have not changed significantly over this period, the use of computed tomography in the diagnosis has increased, and more patients are managed with interventional procedures: surgery in type A AAD and endovascular therapy in type B AAD; with these changes in care, there has been a significant decrease in overall in-hospital mortality in type A AAD but not in type B AAD. Herein, we summarized the key lessons learned from this international registry of patients with AAD over the past 20 years.

Clinical and pathologic findings of aortic dissection at autopsy: Review of 336 cases over nearly 6 decades

BACKGROUND

We aimed to characterize the clinical and pathologic findings of aortic dissection (AD) over a nearly 60-year period.

METHODS

The Jesse E. Edwards Registry of Cardiovascular Disease database was queried for cardiac specimens from autopsies with AD as a diagnosis and compared 2 cohorts: early (1956-1992) and current (1993-2015).

RESULTS

From 1956 to 2015, 338 cases (166 early, 170 current) with AD were included (mean age: 60; 62% male). The AD was 86% type A and 14% type B. Sixty-two percent of cases were under medical care at time of death (61% early, 62% current, P = not significant). Of those under medical care, 63% were not diagnosed prior to death (64% early, 62% current, P = not significant). Risks for dissection did not differ between time intervals and include left ventricular hypertrophy, suggestive of hypertension (84%), prior cardiovascular surgery (38%), bicuspid valve (14%), and connective tissue disease (9%). An intimal tear was identified in the ascending aorta in the majority (68%), followed by descending (14%), root (9.5%), and arch (7%). Aortic rupture occurred in 58%, most frequently in the ascending aorta (41%).

CONCLUSIONS

In a large cardiovascular registry, >60% of cases of AD were not detected clinically and first identified at autopsy. Although diagnostic techniques have significantly improved over the time interval, the percentage of AD discovered at autopsy did not differ from the early to the current era. The most prevalent risk factors for dissection including hypertension and prior cardiovascular surgery remain similar in both time periods. AD death is related to rupture of the aorta in the majority of cases.

Contemporary Management of Ischemic Mitral Regurgitation: A Review

Ischemic mitral regurgitation occurs relatively frequently in patients with coronary artery disease and is associated with an increased long-term risk. The pathophysiology of ischemic mitral regurgitation is vexing and poses both diagnostic and therapeutic challenges, leading to the need for a comprehensive, multidisciplinary approach. The management is largely focused on medical therapy, and for those eligible, coronary revascularization or cardiac resynchronization therapy may be considered. In select patients, mitral valve surgery or catheter-based therapy may be undertaken with careful consideration of the underlying pathophysiology, surgical risk, and expected long-term outcomes. The appropriate evaluation of patients with ischemic mitral regurgitation involves a careful multidisciplinary approach that carefully considers symptomatology, the etiology and severity of the mitral regurgitation, and the assessment of comorbidities and operative risk to individualize the care of these patients.

Delay from Diagnosis to Surgery in Transferred Type A Aortic Dissection

OBJECTIVES

The purpose of this research is to analyze factors associated with delays to surgical management of Type A acute aortic dissection patients.

METHODS

Time from diagnosis to surgery and associated factors were evaluated in 1880 surgically managed Type A dissection patients enrolled in the International Registry of Acute Aortic Dissection.

RESULTS

The majority of patients were transferred (75.7% vs 24.3%). Patients who were transferred had a median delay from diagnosis to surgery of 4.0 hours (interquartile range 2.5-7.2 hours), compared with 2.3 hours (interquartile range 1.1-4.2 hours; P < .001) in nontransferred patients. Among patients who were transferred, those with worst-ever, posterior, or tearing chest pain those with severe complications, and those receiving transthoracic echocardiogram prior to a transesophageal echocardiogram or as the only echocardiogram were treated more quickly. Those undergoing magnetic resonance imaging, or who had prior cardiac surgery, had longer delays to surgery. Among nontransferred patients, those with coma were treated more quickly. In both groups, patients presenting with emergent conditions such as cardiac tamponade, hypotension, or shock had more rapid treatment. Among transferred patients, surviving patients had longer delays (4.1 [2.6-7.8] hours vs 3.3 [2.0-6.0] hours, P = .001). Overall mortality did not differ between patients who were transferred vs not (19.3% vs 21.1%, P = .416).

CONCLUSION

Simply being transferred added significantly to the delay to surgery for Type A acute aortic dissection patients, but a number of factors affected its extent. Overall, signs and symptoms leading to a definitive diagnosis or indicating immediate life threat reduced time to surgery, while factors suggesting other diagnoses correlated with delays.

Long-Term Marathon Running Is Associated with Low Coronary Plaque Formation in Women

INTRODUCTION

Marathon running is presumed to improve cardiovascular risk, but health benefits of high volume running are unknown. High-resolution coronary computed tomography angiography and cardiac risk factor assessment were completed in women with long-term marathon running histories to compare to sedentary women with similar risk factors.

METHODS

Women who had run at least one marathon per year for 10-25 yr underwent coronary computed tomography angiography, 12-lead ECG, blood pressure and heart rate measurement, lipid panel, and a demographic/health risk factor survey. Sedentary matched controls were derived from a contemporaneous clinical study database. CT scans were analyzed for calcified and noncalcified plaque prevalence, volume, stenosis severity, and calcium score.

RESULTS

Women marathon runners (n = 26), age 42-82 yr, with combined 1217 marathons (average 47) exhibited significantly lower coronary plaque prevalence and less calcific plaque volume. The marathon runners also had less risk factors (smoking, hypertension, and hyperlipidemia); significantly lower resting heart rate, body weight, body mass index, and triglyceride levels; and higher high-density lipoprotein cholesterol levels compared with controls (n = 28). The five women runners with coronary plaque had run marathons for more years and were on average 12 yr older (65 vs 53) than the runners without plaque.

CONCLUSION

Women marathon runners had minimal coronary artery calcium counts, lower coronary artery plaque prevalence, and less calcified plaque volume compared with sedentary women. Developing coronary artery plaque in long-term women marathon runners appears related to older age and more cardiac risk factors, although the runners with coronary artery plaque had accumulated significantly more years running marathons.

Death and Cardiac Arrest in U.S. Triathlon Participants, 1985 to 2016: A Case Series

BACKGROUND

Reports of race-related triathlon fatalities have raised questions regarding athlete safety.

OBJECTIVE

To describe death and cardiac arrest among triathlon participants.

DESIGN

Case series.

SETTING

United States.

PARTICIPANTS

Participants in U.S. triathlon races from 1985 to 2016.

MEASUREMENTS

Data on deaths and cardiac arrests were assembled from such sources as the U.S. National Registry of Sudden Death in Athletes (which uses news media, Internet searches, LexisNexis archival databases, and news clipping services) and USA Triathlon (USAT) records. Incidence of death or cardiac arrest in USAT-sanctioned races from 2006 to 2016 was calculated.

RESULTS

A total of 135 sudden deaths, resuscitated cardiac arrests, and trauma-related deaths were compiled; mean (±SE) age of victims was 46.7 ± 12.4 years, and 85% were male. Most sudden deaths and cardiac arrests occurred in the swim segment (n = 90); the others occurred during bicycling (n = 7), running (n = 15), and postrace recovery (n = 8). Fifteen trauma-related deaths occurred during the bike segment. Incidence of death or cardiac arrest among USAT participants (n = 4 776 443) was 1.74 per 100 000 (2.40 in men and 0.74 in women per 100 000; P < 0.001). In men, risk increased substantially with age and was much greater for those aged 60 years and older (18.6 per 100 000 participants). Death or cardiac arrest risk was similar for short, intermediate, and long races (1.61 vs. 1.41 vs. 1.92 per 100 000 participants). At autopsy, 27 of 61 decedents (44%) had clinically relevant cardiovascular abnormalities, most frequently atherosclerotic coronary disease or cardiomyopathy.

LIMITATIONS

Case identification may be incomplete and may underestimate events, particularly in the early study period. In addition, prerace medical history is unknown in most cases.

CONCLUSION

Deaths and cardiac arrests during the triathlon are not rare; most have occurred in middle-aged and older men. Most sudden deaths in triathletes happened during the swim segment, and clinically silent cardiovascular disease was present in an unexpected proportion of decedents.

PRIMARY FUNDING SOURCE

Minneapolis Heart Institute Foundation.

Reconstitution of immune cell populations in multiple sclerosis patients after autologous stem cell transplantation

Multiple sclerosis is an inflammatory T cell-mediated autoimmune disease. In a Phase II clinical trial, high-dose immunosuppressive therapy combined with autologous CD34⁺ haematopoietic stem cell transplant resulted in 69·2% of subjects remaining disease-free without evidence of relapse, loss of neurological function or new magnetic resonance imaging (MRI) lesions to year 5 post-treatment. A combination of CyTOF mass cytometry and multi-parameter flow cytometry was used to explore the reconstitution kinetics of immune cell subsets in the periphery post-haematopoietic cell transplant (HSCT) and the impact of treatment on the phenotype of circulating T cells in this study population. Repopulation of immune cell subsets progressed similarly for all patients studied 2 years post-therapy, regardless of clinical outcome. At month 2, monocytes and natural killer (NK) cells were proportionally more abundant, while CD4 T cells and B cells were reduced, relative to baseline. In contrast to the changes observed at earlier time-points in the T cell compartment, B cells were proportionally more abundant and expansion in the proportion of naive B cells was observed 1 and 2 years post-therapy. Within the T cell compartment, the proportion of effector memory and late effector subsets of CD4 and CD8 T cells was increased, together with transient increases in proportions of CD45RA-regulatory T cells (T_regs ) and T helper type 1 (Th1 cells) and a decrease in Th17·1 cells. While none of the treatment effects studied correlated with clinical outcome, patients who remained healthy throughout the 5-year study had significantly higher absolute numbers of memory CD4 and CD8 T cells in the periphery prior to stem cell transplantation.

Transient Aortic Intramural Hematoma Complicating Transaortic Valve Replacement

Acute aortic intramural hematoma, which is a variant of acute aortic syndromes, most frequently occurs spontaneously and typically is treated similar to classic aortic dissection. Here, we describe a case in which an iatrogenic aortic intramural hematoma occurs shortly after transaortic valve replacement. The patient was managed conservatively, and the hematoma quickly resolved as demonstrated by serial imaging.

The interaction between physical activity and obesity gene variants in association with BMI: Does the obesogenic environment matter?

Little is known about how obesity susceptibility single nucleotide polymorphisms (SNPs) interact with moderate to vigorous physical activity (MVPA) in relation to BMI during adolescence, once obesogenic neighborhood factors are accounted for. In race stratified models, including European (EA; N=4977), African (AA; N=1726), and Hispanic Americans (HA; N=1270) from the National Longitudinal Study of Adolescent to Adult Health (1996; ages 12-21), we assessed the evidence for a SNPxMVPA interaction with BMI-for-age Z score, once accounting for obesogenic neighborhood factors including physical activity amenities, transportation and recreation infrastructure, poverty and crime. Eight SNPxMVPA interactions with suggestive significance (p<0.10; three in each EA, and AA, two in HA) were observed showing attenuation on BMI-for-age Z score in adolescents with ≥5 versus <5 bouts/week MVPA, except for rs10146997 (near NRXN3). Findings were robust to the inclusion of neighborhood-level variables as covariates. These findings suggest that any attenuation from MVPA on a genetic susceptibility to obesity during adolescence is likely not operating through obesogenic neighborhood factors.

Relation of Doppler Tissue Imaging Parameters With Heart Failure Progression in Hypertrophic Cardiomyopathy

Refractory progressive heart failure (HF) is becoming the predominant cause of mortality in nonobstructive hypertrophic cardiomyopathy (HC). To anticipate development of this important and often unpredictable clinical course, we investigated whether left ventricular diastolic dysfunction, assessed by echocardiographic Doppler parameters, could identify a subset of patients with HC without obstruction at rest who would experience progression of HF. Diastolic function parameters, assessed by Doppler tissue imaging (DTI), mitral inflow, and pulmonary venous flow were measured in 274 consecutive adult patients with HC evaluated from 2003 to 2007. DTI and other diastolic and clinical/demographic parameters were measured against the composite end point of HF/death, heart transplantation, or progression to advanced New York Heart Association functional class III/IV symptoms and sudden death (SD)/implantable defibrillator (ICD) interventions. HF end points were reached in 19 of 274 patients (7%) over a follow-up period of 4.0 ± 2.3 years. Variables significantly associated with HF outcome by univariate analysis included male gender, initial New York Heart Association class II, lower ejection fraction, and reduced septal and lateral e' mitral annular tissue velocities. Multivariable analysis showed only a reduced lateral e' mitral annular tissue velocity to be independently associated with the composite HF end points (HR 0.77; 95% CI 0.65 to 0.91; p = 0.003). In addition, estimated pulmonary arterial systolic pressure and extensive late gadolinium enhancement by magnetic resonance were also associated with HF outcome (p = 0.04 and p <0.001, respectively). No Doppler (or clinical) variable was associated with SD/appropriate ICD interventions. In conclusion, in HC without outflow obstruction at rest, diastolic dysfunction, evidenced by DTI-reduced lateral e' mitral annular tissue velocity, was associated with adverse long-term HF outcome but was unrelated to SD. This echocardiographic marker provides a potential noninvasive strategy for anticipating progressive HF in this HC patient group.

Patho-Histological Findings of Annular Rupture Related to Left Ventricular Outflow Tract (LVOT) Calcification Following Transcatheter Aortic Valve Replacement (TAVR)

Peri-aortic hematoma has been recently described as a potentially life-threatening complication following transcatheter aortic valve replacement (TAVR). Patient- and procedure-related factors exist that predispose to peri-aortic hematoma formation, which can progress to myocardial rupture at the aortic root-myocardial junction. While conservative therapy with blood pressure control is the expectant management following peri-aortic hematoma formation, myocardial rupture can occur at the site of the aortic annulus. Hence, interventionists and echocardiologists must be prepared for emergent intervention to salvage the patient once the complication is recognized. The present report highlights the patho-histological findings related to left ventricular outflow tract calcification following TAVR.

Influence of SNP*SNP interaction on BMI in European American adolescents: findings from the National Longitudinal Study of Adolescent Health

BACKGROUND

Adolescent obesity is predictive of future weight gain, obesity and adult onset severe obesity (body mass index [BMI] ≥40 kg m(-2) ). Despite successful efforts to identify Single Nucleotide Polymorphisms (SNPs) influencing BMI, <5% of the 40-80% heritability of the phenotype has been explained. Identification of gene-gene (G-G) interactions between known variants can help explain this hidden heritability as well as identify potential biological mechanisms affecting weight gain during this critical developmental period.

OBJECTIVE

We have recently shown distinct genetic effects on BMI across the life course, and thus it is important to examine the evidence for epistasis in adolescence.

METHODS

In adolescent participants of European descent from wave II of the National Longitudinal Study of Adolescent Health (Add Health, n = 5072, ages 12-21, 52.5% female), we tested 34 established BMI-related SNPs for G-G interaction effects on BMI z-score. We used mixed-effects regression, assuming multiplicative interaction models adjusting for age, sex and geographic region, with random effects for family and school.

RESULTS

For 28 G-G interactions that were nominally significant (P < 0.05), we attempted to replicate our results in an adolescent sample from the Childhood European American Cohort from Philadelphia. In the replication study, one interaction (PRKD1-FTO) was significant after correction for multiple testing.

CONCLUSIONS

Our results are suggestive of epistatic effects on BMI during adolescence and point to potentially interactive effects between genes in biological pathways important in obesity.

Internal medicine point-of-care ultrasound assessment of left ventricular function correlates with formal echocardiography

PURPOSE

Although focused cardiac ultrasonographic (FoCUS) examination has been evaluated in emergency departments and intensive care units with good correlation to formal echocardiography, accuracy for the assessment of left ventricular systolic function (LVSF) when performed by internal medicine physicians still needs independent evaluation.

METHODS

This prospective observational study in a 640-bed, academic, quaternary care center, included 178 inpatients examined by 10 internal medicine physicians who had completed our internal medicine bedside ultrasound training program. The ability to estimate LVSF with FoCUS as "normal," "mild to moderately decreased," or "severely decreased" was compared with left ventricular ejection fraction (>50%, 31-49%, and <31%, respectively) from formal echocardiography interpreted by a cardiologist.

RESULTS

Sensitivity and specificity of FoCUS for any degree of LVSF impairment were 0.91 (95% confidence interval [CI] 0.80, 0.97) and 0.88 (95% CI 0.81, 0.93), respectively. The interrater agreement between internal medicine physician-performed FoCUS and formal echocardiography for any LVSF impairment was "good/substantial" with κ = 0.77 (p < 0.001), 95% CI (0.67, 0.87). Formal echocardiography was classified as "technically limited due to patient factors" in 20% of patients; however, echogenicity was sufficient in 100% of FoCUS exams to classify LVSF.

CONCLUSIONS

Internal medicine physicians using FoCUS identify normal versus decreased LVSF with high sensitivity, specificity, and "good/substantial" interrater agreement when compared with formal echocardiography. These results support the role of cardiac FoCUS by properly trained internal medicine physicians for discriminating normal from reduced LVSF.