American Heart Association

Monthly Archives: March 2016

Breakfast Intake Inversely Associated With Incident Stroke

Neal S. Parikh, MD

Kubota Y, Iso H, Sawada N, Tsugane S, The JPHC Study Group. Association of Breakfast Intake With Incident Stroke and Coronary Heart Disease: The Japan Public Health Center–Based Study. Stroke. 2016

The association between breakfast intake and good health is often touted in popular culture.

The authors cite studies demonstrating associations between skipping breakfast and multiple metabolic derangements and vascular risk factors including obesity, hypertension, dyslipidemia and glucose intolerance. Given these findings and the findings of a study of male US health professionals suggesting an inverse relationship between breakfast intake and coronary heart disease, the authors studied the association between breakfast intake and incident stroke and coronary heart disease.

The study was a population-based, prospective study using the Japan Public Health Center-Based (JPHC) study. Of 140,420 Japanese adults who were eligible, the study included 82,772 participants who had answered a breakfast intake questionnaire in the late 1990s and were free of prevalent stroke or coronary heart disease. Breakfast intake was defined as frequency of breakfast intake per week with daily breakfast as the reference. Covariates included age, sex, BMI, hypertension, hyperlipidemia, diabetes, blood pressure and cholesterol medications, smoking, exercise, sleep, stress, cohabitation, nature of employment, alcohol intake, caloric intake, and intake of vegetables, fruit, fish, soy, dairy, nuts, fat, fiber, and sodium. The outcomes were incident stroke (ischemic, subarachnoid hemorrhage, cerebral hemorrhage), MI, and sudden cardiac death.

The 82,772 participants provided 1,050,030 patient-years of follow-up. Participants who ate breakfast less frequently were less healthy and less likely to be on appropriate medication (e.g. for hypertension and hyperlipidemia). There were 4,642 cases of coronary heart disease and 3,772 strokes (including 1050 cerebral hemorrhages, 417 subarachnoid hemorrhages, 2,286 ischemic strokes).

After adjusting for potential confounders including dietary and lifestyle factors, total cardiovascular disease was associated with complete breakfast omission (HR, 1.14; CI 1.01-1.27) as was total stroke (HR 1.18, CI 1.04-1.34). An association was seen between breakfast omission and cerebral hemorrhage (HR, 1.36, CI 1.10-1.70) but not with coronary heart disease, subarachnoid hemorrhage, or cerebral infarction. The association between breakfast omission and stroke was only seen in non-users of anti-hypertensive medications.

The main limitation is that breakfast intake frequency was a time-fixed variable, which means that the methods did not account for the possibility of breakfast habits changing over time. Second, those omitting breakfast were less healthy, which raises the real possibility of residual confounding, especially as the confidence interval nearly crossed 1.0 for total cardiovascular disease.

Nonetheless, as the authors explain, there is a plausible causal pathway from breakfast omission to morning hypertension and cerebral hemorrhage. Additionally, to its merit, the study exhaustively controlled for vascular risk factors and dietary and lifestyle factors. This study suggests that failure to regularly eat breakfast is associated with cardiovascular disease, particularly hemorrhagic stroke. It may therefore indeed be healthful to eat breakfast daily.

Assessing Mismatch Using DWI and FLAIR Predicts Favorable Outcome Following Recanalization With IV-tPA

Jay Shah, MD

Legrand L, Tisserand M, Turc G, Edjlali M, Calvet D, Trystram D, et al. Fluid-Attenuated Inversion Recovery Vascular Hyperintensities–Diffusion-Weighted Imaging Mismatch Identifies Acute Stroke Patients Most Likely to Benefit From Recanalization. Stroke. 2016

Perfusion-Diffusion mismatch on MRI has been proposed to select ischemic stroke patients for revascularization therapy. However, this strategy is time consuming and requires gadolinium. The authors previously have reported using mismatch between Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) and diffusion for penumbral evaluation. FVH represent slow retrograde flow in leptomeningeal collaterals and are thought to represent impaired but viable tissue. The authors hypothesize that recanalization after IV-tPA would have better outcomes within FVH-DWI mismatch patients than non-mismatch patients. 

This study was a retrospective analysis of a prospective registry of patients treated exclusively with standard IV-tPA dosing for acute stroke between 2004-14. Other inclusion criteria included proximal M1 occlusion, pre-treatment and 24-hour follow-up MRI, and 3 month modified rankin scale (mRS) score. FVH-DWI mismatch was considered present when FVH extended beyond boundaries of the cortical DWI lesion. In total, 164 patients were included in the analysis. 121 patients had FVH-DWI mismatch. Complete recanalization occurred in 50 patients. Association between recanalization and favorable outcome was significant in patients with FVH-DWI mismatch (OR= 16.2). 

This study shows that DWI and FLAIR images can identify patients who are more likely to benefit from recanalization and the authors propose that this modality can be used as a surrogate to perfusion imaging. However, it is clearly understood that clinical outcomes in acute ischemic stroke is strongly associated with recanalization of the occluded artery. Non-mismatch patients also demonstrated benefit, albeit to a lesser degree and therefore revascularization should not be withheld for a perceived lack of benefit. Furthermore, all patients within this study had M1 occlusion but did not undergo endovascular intervention which is now established as the standard of care. For such patients, if recanalization can be achieved according to guideline recommendations, there should not be a need for further penumbral evaluation. However, in patients with a prolonged presentation or an unknown time of onset, assessment of mismatch could provide utility in selecting appropriate patients. Further studies should focus on this patient population.

The Nuts and Bolts of Organizing a Telestroke Network: A Challenging but Achievable Goal

International Stroke Conference (ISC)
February 17-19, 2016

February 17, 2016
The delicate intricacies of Telestroke networks were fully exposed in this interesting session at the International Stroke Conference. The discussion mainly focused on how to set-up Telestroke networks including organizing hubs and spokes, quality and outcome reporting and economic, legal, licensing and credentialing considerations. The highlights have been summarized below.

This field has grown significantly since it origins back in the 1920s. However, it wasn’t until more recent years that it became mainstream care for acute stroke patients after an inflow of literature proved this technology to be a cost-effective intervention from both a societal and hospital perspective. There are essentially three Telestroke network models. The Hub-Spoke one in which a tertiary center provides the service to satellite primary centers, the distributed model where the expertise is delivered by a third party and patients are transferred to available tertiary centers and the Hub-less model where physicians that belong to different institutions take Telestroke call on a rotatory basis to provide regional coverage. Regardless of the model, hubs and spokes may face multiple challenges while trying to institute this technology including, but not limited to, cost burden for small hospitals, commitment from staff for call coverage, access to outside hospital data, ability to interact with the patients and perform accurate physical examinations and the ability to obtain follow-up information on the cases. Often, quality maintenance may become challenging and time consuming requiring 24/7 availability of clinical and technological support, ongoing staff training, hardware and software technology updates, and imaging-sharing capabilities, among others. One topic that was highlighted by several speakers was the need to implement a signed agreement between parties that clearly delineates the type of service provided whether it is consultation only or if ownership privileges are allowed. Unfortunately, no quality measures have been created specifically for Telestroke purposes but national quality improvement strategies such as Target Stroke and Get-With-The-Guidelines can be used for this purpose. Legal and Licensing issues are most often related to the state where this technology is practiced, most importantly the state where the patient that receive care is. Overall, Telestroke has proven to be a reliable practice with minimal variation in stroke assessments (NIHSS) when compared to standard examination, which reduces door-to-needle times and increases the rate of intravenous t-PA administration and endovascular acute stroke treatment leading to better outcomes.

Telestroke is on its way of becoming a large electronic stroke unit that allows stroke experts and tertiary centers connect to stroke patients who need quality diagnosis and treatment regardless of their location. Patient enrollment to clinical trials is another future potential application of this technology. Watch out for this developing field, much more will come and remember: “Successful Telestroke Networks pay attention to details”.

– Luciana Catanese, MD

Improving Access to Stroke Care Through Advocacy

AAN Neurology on the Hill

March 1, 2016
On Super Tuesday, March 1, 2016, members of the American Academy of Neurology met with our lawmakers to advocate for an act of congress to increase availability of acute stroke care. We were joined by a delegation of stroke patient advocates from the AHA/ASA.

The bill is called the FAST Act (Senate 1465, House 2799), which stands for Furthering Access to Stroke Telemedicine. Medicare currently only reimburses for telestroke consultation for patients presenting to hospitals in rural areas, and this bill seeks to expand coverage for patients originating in urban and suburban areas as well.

Though telemedicine has clear utility for patients in rural areas, the vast majority of patients fall victim to stroke in urban and suburban areas. Neurologists and stroke centers are more common in these areas, but this is not universally true. Increasing the availability of telestroke consultation could increase the rate and speed of acute ischemic stroke treatment in more areas.

A number of studies have examined safety, outcomes and cost-effectiveness of telestroke. Most of the data regarding telestroke come from studies in rural settings, in which telestroke systems safely and effectively aid in the treatment of stroke.1,2 Additionally, in urban Madrid, implementation of telestroke was associated with higher rates of IV-tPA administration, faster door-to-needle times, and a lower 3-month mRS scores.3 In terms of cost effectiveness, telestroke networks are at least cost-neutral and likely result in societal cost savings.2,4 Telestroke may have additional unique benefits in urban and suburban areas such as refining access to endovascular therapy.

Politically, this bill is considered a “win-win” bill. It is intended to benefit patients through expansion of coverage, yet is nonetheless expected, by AHA/ASA estimates, to generate considerable savings through the reduction of nursing home and long-term care facility use. Additionally, it has true bipartisan support with at least 25 Democrat and 25 Republican co-sponsors in the house. There is, therefore, a real possibility of this expansion becoming codified in law, whether through passage of the FAST Act or incorporation into other health care legislation.

The FAST Act would require Medicare to reimburse hospitals for telestroke regardless of geography, thereby allowing hospitals to build and strengthen the infrastructure for acute stroke care. The benefits are clear and may exceed expectations.

Concerned readers are encouraged to write to their senators and representatives. Members of the American Academy of Neurology can do so through the Action Center on the AAN website.

– Neal S. Parikh, MD

1. Stroke. 2014;45:2739-44.
2. Stroke. 2014;45:1876-80. [Review]
3. J Neurol. 2014;261:1768-73.
4. Am J Manag Care. 2013;19:976-85.

Appropriate Patient Selection for Endovascular Intervention: Common Clinical Challenges and Dilemmas

International Stroke Conference (ISC)
February 17-19, 2016

February 17, 2016
At the International Stroke Conference, a panel of experts discussed various clinical questions in regards to patient selection for endovascular intervention that were not addressed in recent trials. This questions include stroke severity, age, need for imaging, time, and location.

Dr. Khatri discussed stroke severity. Mild strokes were excluded from the recent endovascular trials thus leading to the ASA recommendation of endovascular intervention for strokes with NIHSS > 6. Within the trials, only 14 patients were treated with NIHSS 0-5 so treatment affect and benefit within this subset population is relatively unknown. It’s possible that such patients are mislabeled as “mild” stroke and inappropriately excluded from acute revascularization therapy. The focus should be less on absolute NIHSS number but rather on actual disability. An ACA infarct can register a low NIHSS but can be extremely disabling and should be offered revascularization therapy.

Dr. Powers discussed the important risk factor of age and whether there should be an upper limit. The data suggests limited benefit beyond age > 80 but there are no controls. What is clear from the data that untreated patients do worse and the focus should be on relative benefit rather than absolute benefit. A consensus is age alone should not be a contraindication and treatment decisions should factor baseline health and functional status. There are sufficient anecdotal evidence of successful endovascular treatment with good clinical outcome in octogenarians with a normal functional status at baseline.

Dr. Yoo discussed perhaps one of the more controversial topics of how much imaging is actually required before proceeding with intervention. Many hospitals have adopted CT and CTA scan as their “default” imaging in order to determine eligibility and this has also been adopted within guidelines as well. The dilemma becomes when there are CT hypodensities and more data is needed for ASPECTS of 0-4. In this scenario, it is reasonable to proceed with perfusion imaging to assess for penumbra. DEFUSE-2 is on-going study addressed to determine if perfusion imaging can identify patients for clot retrieval.

Dr. Jovin addressed the important factor of time and when is it getting too late for intervention. It has been well established that collaterals determine rate of infarct growth. Furthermore, patients with good collaterals have also been shown to do well without intervention as well. Therefore, selecting patients based solely on collaterals may be a self-fulfilling prophecy. Two trials are currently underway evaluating outcomes in patients with delayed presentation.

Lastly, Dr. Noguiera discussed the influence of site of occlusion on treatment. Vast majority of patients treated in the trials were large proximal artery occlusion (ICA, M1). With improving technology, clot retrieval is achievable for other sites including ACA, PCA, and M3. However, data on such infarcts are sparse. Only 3 ACA occlusions were included within MR CLEAN. The decision to intervene upon smaller vessels should be based upon risk and benefit. There is greater risk to intervene upon smaller vessels, especially as tortuousity increases, and decision should be based upon other factors including stroke syndrome and anatomy.

– Jay Shah, MD

Regional Pre-hospital Triage and Treatment of Stroke Patients in the New Era of Endovascular Therapy

International Stroke Conference (ISC)
February 17-19, 2016

February 17, 2016
This ISC session focused on a hot-topic: pre-hospital stroke triage and care. We learned about optimizing EMS triage protocols by learning from trauma and MI models, improving EMS providers’ clinical recognition of stroke, when to bypass local PSCs in favor of a CSC, and the role of technology in the pre-hospital setting.

Dr. McMullan from Cincinnati began the session discussing his personal experience as a prior EMT, and described the various levels of training that emergency responders may have. While the advanced technology we are coming up with is great, we can’t realistically have that everywhere and so we need to do our best in getting patients to the most appropriate location with the resources we have. We know that there are better outcomes at high volume/specialty centers, and that delays from secondary transfer decrease outcomes. However, we must recognize the limits of comprehensive centers, in terms of number of patients that can be accommodated. In the trauma example given, we learned that up to a 40% “overtriage” rate is acceptable (sending a lower level trauma to a higher level of care based on initial assessment) but that the acceptable rate of “undertriage” is zero. He ended with the recommendation to “put patients first.” While this sounds obvious, I took it to mean that we should create and use algorithms and protocols to improve patient care, but not allow the rules to impede achievement of this goal. Triage algorithms can be complicated and if there is any hesitation on where to send the patient, keeping this mantra at the forefront of our minds will ensure the best care for our patients.

Dr. Katz, also from Cincinnati, followed with a discussion on EMS identification of severe strokes. He acknowledged that there is no consensus on the definition of a large vessel occlusion based on NIHSS, but that certain features are more suggestive. Multiple stroke scales have been created and tested, including the LMAS, 3ISS, C-STAT (previously the CPSS), and RACE scales. We have not yet decided on a universal scale to use, and further testing needs to be done. Ultimately, the scale has to be predictive of a large vessel occlusion in order for EMS to use it to triage patients who should bypass PSCs. The optimal scale will be easy to administer, have good inter-rater reliability, be validated for LVO prediction, and tested in a large real life population of patients by real EMS providers.

Dr. Asimos from Charlotte, NC, continued the discussion with a review of different stroke triage models and the factors which influence our decision to bypass local PSCs for a CSC. Realizing that there is no “easy” tool for in-the-field determination of LVO, and that some patients will arrive at a CSC without an amenable lesion, we need to determine the NNB (number needed to bypass) for taking patients directly to a CSC in lieu of stopping at a local PSC. Based on a trial conducted in Florida, for every 8 patients who bypassed PSCs, 1 received endovascular therapy. Dr. Asimos recommended that we look at the door to needle times of PSCs (often slower than CSCs), and include that in our decision model. There is also variation in the time it takes to image patients at PSCs, and we should consider which imaging is actually necessary prior to transfer. A study at Emory found that doing CTA and CTP prior to transfer added an hour to the time it took the patient to arrive at the CSC. He concluded by stating that we need target metrics, both for pre-hospital and inter-hospital transfers. I think we need to identify each component of the transfer process to determine where there are time delays and whether skipping that component (i.e. CTA CTP which will most likely be repeated at the CSC prior to taking the patient to endovacscular) is possible. If that reduction in time delay is enough to improve outcomes, we can streamline and standardize the expectations we set for transfer protocols.

Dr. Heinrich Audebert concluded the session with a discussion of the role of technology in pre-hospital triage and care. He pointed out that while only 1-5% of stroke patients are eligible for endovascular therapy, and about 20% are eligible for tPA, almost all patients are eligible for specialized stroke ward treatment. He described the results of the PHANTOM-S trial, in which the CT-equipped STEMO ambulance was compared to standard of care. Fewer stroke patients were transported to hospitals without a stroke unit during STEMO weeks (~4%) than during control weeks (~10%). Dr. Audebert recommended a preliminary triage system before deploying STEMO, as well as an on-call telestroke physician to do an evaluation in the ambulance. While it would be ideal to have a CT scanner in each ambulance, or at least have one available for a larger area which can be deployed after some preliminary triage, this may not be possible given the resources required. I think it is much more feasible to employ affordable telemedicine options, which have previously been explored, to better triage patients to the right place and ensure optimal care.

Overall, a great session on a rapidly growing aspect of stroke care. This same session will likely be very different next year – looking forward to it.

– Ilana Spokoyny, MD