Effects of 24-Hour Blood Pressure and Heart Rate Recorded With Ambulatory Blood Pressure Monitoring on Recovery From Acute Ischemic Stroke

Importance of blood pressure monitoring in the acute phase of stroke. An update

INTRODUCTION

The evaluation of blood pressure (BP) is essential in the acute phase of stroke. Although ambulatory blood pressure monitoring (ABPM) is a validated method for BP control, there are few studies assessing the usefulness of ABPM in the acute phase of stroke.

DEVELOPMENT

A systematic review was carried out according to the PRISMA criteria in the PubMed/Medline and Scopus databases. Those articles that analysed the use of ABPM in the first days after suffering a stroke from 1992 to 2022 were selected. Those articles focused on the post-acute or sequelae phase of the stroke, with a sample size of less than 20 and those where the primary objective was different from the defined one. A total of 28 articles were included.

CONCLUSIONS

The use of ABPM in patients with recent stroke demonstrates that the normal circadian profile of BP is altered in more than two-thirds of patients and that this will be fundamentally conditioned by the haemodynamic changes that occur on autoregulation of cerebral blood flow, the type of stroke or the response to treatment. Furthermore, these changes in BP have prognostic implications and are correlated with functional status, stroke recurrence and mortality, among others. However, although they continue to be a growing area of research, new studies are needed to clarify the real role of this technique in patients with acute stroke.

Blood pressure variability predicts poor outcomes in acute stroke patients without thrombolysis: a systematic review and meta-analysis

BACKGROUND

Stroke is a significant medical condition, and blood pressure stands out as the most prevalent treatable risk factor associated with it. Researches link blood pressure variability (BPV) with stroke; however, the specific relationship between with the outcomes of stroke patients remains unclear. As blood pressure variability and mean blood pressure are interrelated, it remains uncertain whether BPV adds additional information to understanding the outcome of acute stroke patients.

OBJECTIVE

To systematically review studies investigating the association between blood pressure variability and prognosis in acute stroke patients.

METHODS

Embase, PubMed, Web of Science, and the Cochrane Library were searched for English language full-text articles from the inception to 1 January 2023. Stroke patients aged ≥ 18 years were included in this analysis. Stroke types were not restricted.

RESULTS

This meta-analysis shows that higher systolic blood pressure variability is linked to a higher risk of poor outcome, including function disability, mortality, early neurological deterioration, and stroke recurrence, among acute stroke patients without thrombolysis. A higher diastolic blood pressure variability is linked with to a higher risk of mortality and functional disability.

CONCLUSIONS

This review reveals that blood pressure variability is a novel and clinically relevant risk factor for stroke patients' outcome. Future studies should investigate how best to measure and define BPV in acute stroke. Larger studies are warranted to provide more robust evidence in this area.

Association of Blood Pressure Variability With Death and Discharge Destination Among Critically Ill Patients With and Without Stroke

BACKGROUND AND OBJECTIVES

It is unclear whether blood pressure variability's (BPV) association with worse outcomes is unique to patients with stroke or a risk factor among all critically ill patients. We (1) determined whether BPV differed between patients with stroke and nonstroke patients, (2) examined BPV's associations with in-hospital death and favorable discharge destination in patients with stroke and nonstroke patients, and (3) assessed how minimum mean arterial pressure (MAP)-a correlate of illness severity and cerebral perfusion-affects these associations.

METHODS

This is a retrospective analysis of adult intensive care unit patients hospitalized between 2001 and 2012 from the Medical Information Mart for Intensive Care III database. Confounder-adjusted logistic regressions determined associations between BPV, measured as SD and average real variability (ARV), and (1) in-hospital death and (2) favorable discharge, with testing of minimum MAP for effect modification.

RESULTS

BPV was higher in patients with stroke (N = 2,248) compared with nonstroke patients (N = 9,085) (SD mean difference 2.3, 95% CI 2.1-2.6, p < 0.01). After adjusting for minimum tertile of MAP and other confounders, higher SD remained significantly associated (p < 0.05) with higher odds of in-hospital death for patients with acute ischemic strokes (AISs, odds ratio [OR] 2.7, 95% CI 1.5-4.8), intracerebral hemorrhage (ICH, OR 2.6, 95% CI 1.6-4.3), subarachnoid hemorrhage (SAH, OR 3.4, 95% CI 1.2-9.3), and pneumonia (OR 1.9, 95% CI 1.1-3.3) and lower odds of favorable discharge destination in patients with ischemic stroke (OR 0.3, 95% CI 0.2-0.6) and ICH (OR 0.4, 95% CI 0.3-0.6). No interaction was found between minimum MAP tertile with SD (p > 0.05). Higher ARV was not significantly associated with increased risk of death in any condition when adjusting for illness severity but portended worse discharge destination in those with AIS (OR favorable discharge 0.4, 95% CI 0.3-0.7), ICH (OR favorable discharge 0.5, 95% CI 0.3-0.7), sepsis (OR favorable discharge 0.8, 95% CI 0.6-1.0), and pneumonia (OR favorable discharge 0.5, 95% CI 0.4-0.8).

DISCUSSION

BPV is higher and generally associated with worse outcomes among patients with stroke compared with nonstroke patients. BPV in patients with AIS and patients with ICH may be a marker of central autonomic network injury, although clinician-driven blood pressure goals likely contribute to the association between BPV and outcomes.

Midday Dipping and Circadian Blood Pressure Patterns in Acute Ischemic Stroke

The purpose of this study was to investigate the alterations in blood pressure (BP) during midday and the changes in circadian BP patterns in the acute phase of ischemic stroke (AIS) with the severity of stroke and their predictive role outcomes within 3 months. A total of 228 AIS patients (a prospective multicenter follow-up study) underwent 24 h ambulatory blood pressure monitoring (ABPM). Mean BP parameters during the day (7:00-22:59), the midday (13:00-16:59), and the night (23:00-6:59), and midday and nocturnal dipping were calculated. Midday SBP dippers had less severe stroke, lower incidence of hypertension and SBP/DBP on admission, lower levels of serum glucose and WBCs, and delayed initiation of ABPM compared to risers. There was a reverse relation between midday SBP dipping and both nocturnal dipping and stroke severity. The "double dippers" (midday and nocturnal dipping) had the least severe stroke, the lowest SBP/DBP on admission, the lowest heart rate from ABPM, and a lower risk of an unfavorable outcome, while the "double risers" had the opposite results, by an approximately five-fold risk of death/disability at 3 months. These findings indicate different circadian BP patterns during the acute phase of AIS, which could be considered a marker of stroke severity and prognosis.

Prognostic significance of 24-h blood pressure and variability indices in the outcome of acute ischaemic stroke

BACKGROUND

The association between blood pressure (BP) levels and BP variability (BPV) following acute ischaemic stroke (AIS) and outcome remains controversial.

AIMS

To investigate the predictive value of systolic BP (SBP) and diastolic BP (DBP) and BPV measured using 24-h ambulatory blood pressure monitoring (ABPM) methods during AIS regarding outcome.

METHODS

A total of 228 AIS patients (175 without prior disability) underwent ABPM every 20 min within 48 h from onset using an automated oscillometric device (TM 2430, A&D Company Ltd) during day time (7:00-22:59) and night time (23:00-6:59). Risk factors, stroke subtypes, clinical and laboratory findings were recorded. Mean BP parameters and several BPV indices were calculated. End-points were death and unfavourable functional outcome (disability/death) at 3 months.

RESULTS

A total of 61 (26.7%) patients eventually died. Multivariate logistic regression analysis revealed that only mean night-time DBP (hazard ratio (HR): 1.04; 95% confidence interval (CI): 1.00-1.07) was an independent prognostic factor of death. Of the 175 patients without prior disability, 79 (45.1%) finally met the end-point of unfavourable functional outcome. Mean 24-h SBP (HR: 1.03; 95% CI: 1.00-1.05), day-time SBP (HR: 1.02; 95% CI: 1.00-1.05) and night-time SBP (HR: 1.03; 95% CI: 1.01-1.05), SBP nocturnal decline (HR: 0.93; 95% CI: 0.88-0.99), mean 24-h DBP (HR: 1.08; 95% CI: 1.03-1.13), day-time DBP (HR: 1.07; 95% CI: 1.03-1.12) and night-time DBP (HR: 1.06; 95% CI: 1.02-1.10) were independent prognostic factors of an unfavourable functional outcome.

CONCLUSIONS

In contrast with BPV indices, ABPM-derived BP levels and lower or absence of BP nocturnal decline in the acute phase are prognostic factors of outcome in AIS patients.

Data lake-driven analytics identify nocturnal non-dipping of heart rate as predictor of unfavorable stroke outcome at discharge

BACKGROUND

Post-stroke heart rate (HR) and heart rate variability (HRV) changes have been proposed as outcome predictors after stroke. We used data lake-enabled continuous electrocardiograms to assess post-stroke HR and HRV, and to determine the utility of HR and HRV to improve machine learning-based predictions of stroke outcome.

METHODS

In this observational cohort study, we included stroke patients admitted to two stroke units in Berlin, Germany, between October 2020 and December 2021 with final diagnosis of acute ischemic stroke or acute intracranial hemorrhage and collected continuous ECG data through data warehousing. We created circadian profiles of several continuously recorded ECG parameters including HR and HRV parameters. The pre-defined primary outcome was short-term unfavorable functional outcome after stroke indicated through modified Rankin Scale (mRS) score of > 2.

RESULTS

We included 625 stroke patients, 287 stroke patients remained after matching for age and National Institute of Health Stroke Scale (NIHSS; mean age 74.5 years, 45.6% female, 88.9% ischemic, median NIHSS 5). Both higher HR and nocturnal non-dipping of HR were associated with unfavorable functional outcome (p < 0.01). The examined HRV parameters were not associated with the outcome of interest. Nocturnal non-dipping of HR ranked highly in feature importance of various machine learning models.

CONCLUSIONS

Our data suggest that a lack of circadian HR modulation, specifically nocturnal non-dipping, is associated with short-term unfavorable functional outcome after stroke, and that including HR into machine learning-based prediction models may lead to improved stroke outcome prediction.

The impact of blood pressure variation on mortality and symptomatic intracerebral hemorrhage in acute stroke patients after thrombolysis

Blood pressure variation (BPV) is a known risk factor for unfavorable stroke outcomes. However, little is known about the association between BPV and short-term outcomes in stroke patients after receiving thrombolytic therapy, namely, recombinant tissue plasminogen activator (rt-PA). We conducted a cross-sectional study in the specialized stroke unit of a tertiary-level hospital. Stroke patients who were eligible for rt-PA were enrolled. Blood pressure (BP) was measured every 4 h for 24 h. The SD, coefficient of variation (CV) and successive variation (SV) of both SBP and DBP were calculated. The final outcomes were symptomatic intracerebral hemorrhage (sICH) or in-hospital death from neurologic complications. A total of 278 patients (49.6% men) were enrolled, mean age was 65 years. The final outcomes were reported in 33 patients (11.9%). All systolic and diastolic BPV profiles were associated with the final outcome. Odds ratios (95% confident interval) were SD, 1.07 (1.02-1.13); CV, 1.10 (1.03-1.18) and SV, 1.05 (1.01-1.09) for SBP, and SD, 1.10 (1.02-1.19); CV, 1.08 (1.01-1.16) and SV, 1.09 (1.02-1.15) for DBP. After adjustment for conventional risk factors, SD, CV and SV of SBP, and SD and SV of DBP were still significantly associated with the final outcome. In conclusion, in-hospital systolic (SD, SV and CV) and diastolic (SV, SD) BPV profiles were associated with death and sICH in stroke patients after rt-PA therapy.

Acute-phase heart rate trajectories and functional outcomes in acute ischemic stroke

The heart rate (HR) trajectory is a dynamic metric that shows how HR changes over time. Previous studies have demonstrated that elevated HR is associated with stroke events. However, little research has been done on the influence of shifting HR throughout the acute period on clinical outcomes. This study aims to investigate the effect of HR trajectories on functional outcomes in patients with acute ischemic stroke (AIS). A total of 981 AIS patients were included in the study. A latent mixture model was used to assess HR trends over the first 7 days following disease onset. The patients were divided into four groups based on different HR trajectories: markedly decreasing in 48 h (T1), mildly decreasing in 48 h (T2), sustained moderate in 7 days (T3), and sustained high in 7 days (T4). Poor outcome was defined as a modified Rankin Scale (mRS) score of ≥3 in 3 months. Logistic regression was used to analyze the correlation between different HR trajectories and outcomes. The incidence of poor outcomes was 9.02%, 10.80%, 11.79%, 16.36% in T1 (n = 133), T2 (n = 352), T3 (n = 441), and T4 (n = 55) groups, respectively. Compared with T1 group, T4 group was significantly associated with a higher risk of poor outcome at 3 months (odds ratio = 3.00, 95% confidence interval = 1.06-8.54, p value = .0392). This suggests that in AIS patients, a sustained high HR trajectory is linked to a greater likelihood of poor functional outcome than a markedly decreasing HR trajectory. HR trajectories demonstrate the utility of repeated HR measurements for outcome assessment.

Parathyroidectomy Is Associated with Reversed Nondipping Heart Rate That Impacts Mortality in Chronic Kidney Disease Patients

OBJECTIVE

Nondipping heart rate (HR), defined as a night/day HR ratio >0.90, has been associated with increased mortality in epidemiologic studies. However, its prognostic value in stage 5 chronic kidney disease (CKD5) patients and the effects of parathyroidectomy (PTX) on nondipping HR remain unknown.

METHODS

This case-control study of 162 healthy controls and 502 CKD5 patients was performed between 2011 and 2018, in which CKD5 patients were further divided into non-PTX (n = 186) and severe secondary hyperparathyroidism (SHPT) with PTX (n = 316) subgroups. Each participant underwent 24-hour Holter monitoring for HR ratio. Mortality was followed up in CKD5 patients (median time: 46.0 months).

RESULTS

The HR ratio in CKD5 patients was higher than in controls (0.92 ± 0.08 vs 0.81 ± 0.08, P <.001), associated with a 44% increase in mortality risk per 0.1 increment (hazard ratio, 1.44; 95% CI: 1.02-2.03; P =.04), and was positively related to serum intact parathyroid hormone levels (P <.001). PTX reversed nondipping HR in SHPT patients (n = 50, median time: 6.3 months, P <.001). Survival probabilities for PTX (n = 294) were better than non-PTX (n = 47) (hazard ratio, 0.31; 95% CI: 0.14-0.67; P <.01) in SHPT patients (serum intact parathyroid hormone >500.0 pg/mL).

CONCLUSION

CKD5 patients displayed a nondipping HR pattern, which is a prognostic marker of all-cause mortality. PTX for SHPT patients was associated with a reversal in nondipping HR ratio, which may mediate a better outcome.

Ambulatory blood pressure profile and stroke recurrence

OBJECTIVES

To establish a new ambulatory blood pressure (ABP) parameter (24-hour ABP profile) and evaluated its performance on stroke outcome in ischaemic stroke (IS) or transient ischaemic attack (TIA) patients.

METHODS

The prospective cohort consisted of 1996 IS/TIA patients enrolled for ABP monitoring and a 3-month follow-up for stroke recurrence as outcome. Profile groups of systolic blood pressure (SBP) were identified via an advanced functional clustering method, and the associations of the profile groups and conventional ABP parameters with stroke recurrence were examined in a Cox proportional hazards model.

RESULTS

Three discrete profile groups (n=604, 781 and 611 in profiles 1, 2 and 3, respectively) in 24-hour ambulatory SBP were identified. Profile 1 resembled most to the normal diurnal blood pressure pattern; profile 2 also dropped at night, but climbed earlier and with higher morning surge; while profile 3 had sustained higher nocturnal SBP without significant nocturnal SBP decline. The incidence of stroke recurrence was 2.9%, 3.9% and 5.5% in profiles 1, 2 and 3, respectively. After adjustment for covariates, profile 3 was significantly associated with higher risk of stroke recurrence with profile 1 as reference (HR 1.76, 95% CI: 1.00 to 3.09), while no significant difference was observed between profiles 2 and 1 (HR 1.22, 95% CI: 0.66 to 2.25). None of conventional ABP parameters showed significant associations with the outcome.

CONCLUSIONS

Ambulatory 24-hour SBP profile is associated with short-term stroke recurrence. Profiles of ABP may help improve identification of stroke recurrence by capturing the additive effects of individual ABP parameters.

Short-term outcome after ischemic stroke and 24-h blood pressure variability: association and predictors

To examine the association between blood pressure (BP) variability measured within 24 h after admission for acute ischemic stroke and functional outcome 30 days after stroke onset and to find outcome predictors. A total of 174 patients were included in this retrospective study. Supine BP was measured every 4 h during the first 24 h after admission. The functional outcome was assessed using the modified Rankin Scale. BP parameters including systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP) were examined. A set of six variability indices was calculated, including standard deviation (SD), successive variation (SV), difference between maximum and minimum value (DMM), and maximal successive change (MSC). Patients with high SBP or PP variability measures were significantly more likely to develop an unfavorable outcome. All PP variability indices displayed the highest correlations with the outcome. This association was confirmed in logistic regression analysis, both in univariable model and a model adjusted to the baseline National Institute of Health Stroke Scale score and mean BP (the OR for an unfavorable outcome following a 10-mmHg increase in SD, SV, MSC, and DMM parameters was in the interval 1.4-2.7, p < 0.05). Following receiver operating characteristic analysis, the PP parameters yielded area under the curve (AUC) values between 0.654 and 0.666, p < 0.005. Thus, in the acute phase of ischemic stroke, the SD and MSC indices of PP variability during the first 24 h after admission were robustly associated with patients' 30-day outcomes and served as predictors of unfavorable outcomes with thresholds of 14 and 26 mmHg, respectively.

Effects of vascular compression on the rostral ventrolateral medulla for blood pressure variability in stroke patients

BACKGROUNDS

Vascular compression of the rostral ventrolateral medulla (RVLM) has been associated with hypertension or blood pressure (BP) variability. For acute ischemic stroke patients, increased BP variability may cause poor functional outcomes. We tested the hypothesis that RVLM compression was associated with increased BP variability or stroke outcome in acute ischemic stroke patients.

METHODS

Acute ischemic stroke patients (n = 622) with 24-h ambulatory BP monitoring during the subacute phase of stroke (median 9 days from onset) were retrospectively studied. Variability in BP was evaluated with the SD and coefficient of variation of SBP and DBP. The morning surge was also evaluated. The presence of RVLM compression was evaluated using time-of-flight three-dimensional MRI. A poor outcome was defined as a modified Rankin Scale score of 3-6 at 3 months.

RESULTS

Patients with RVLM compression (n = 213) had significantly higher 24-h SBP mean, 24-h SBP SD, 24-h SBP coefficient of variation, 24-h DBP mean, 24-h DBP SD, and 24-h DBP coefficient of variation values and a higher prevalence of morning surge than those without (n = 409). Multiple regression analysis revealed that RVLM compression was associated with increased SBP variability, DBP variability, and morning surge. Despite the significant association between RVLM compression and BP variability, RVLM compression was not associated with poor stroke outcome.

CONCLUSION

Although RVLM compression was closely associated with BP variability in the subacute ischemic stroke phase, an effect of RVLM compression on stroke outcome was not observed.

Being at risk of malnutrition predicts poor outcomes at 3 months in acute ischemic stroke patients

BACKGROUND

Malnutrition is confirmed to be associated with poor outcomes in stroke patients. The present study aimed to confirm that being at risk of malnutrition assessed by Nutritional Risk Screening Tool 2002 (NRS-2002) and the Controlling Nutritional Status (CONUT) score predicts poor outcomes at 3 months in acute ischemic stroke (AIS) patients.

METHODS

In total, 682 patients with AIS were recruited within 7 days of stroke onset consecutively and 110 were dropped out. They were screened for risk of malnutrition using NRS-2002 and the CONUT score. The primary outcome is the follow-up modified Rankin Scale (mRS) score. Poor outcomes were defined as an (mRS) score ≥ 3 at 3 months post discharge.

RESULTS

There was a significant difference in the mRS score at 3 months between patients at risk of malnutrition compared to those not at risk assessed by NRS-2002(P < 0.001) and CONUT (P = 0.011). The logistic regression model showed that the risk of malnourishment (according to NRS-2002), low risk of malnourishment (according to CONUT), and the moderate-to-severe risk of malnourishment (according to CONUT) were associated with higher risk of poor outcomes at 3 months (P < 0.001, P = 0.033, and P = 0.007). The multivariate logistic regression model (adjusted for confounding factors) demonstrated that the risk of malnourishment, according to the NRS-2002, was associated with the increasing risk of poor outcomes at 3 months (odds ratio = 2.31; 95% CI: 1.24-4.30; P = 0.008).

CONCLUSIONS

The risk of malnutrition assessed by NRS-2002 and CONUT can predict poor outcomes at 3 months in AIS patients. NRS-2002 is superior to CONUT in predicting poor outcomes at 3 months.

Role of 24-Hr Blood Pressure Variability as a Target Therapeutic Risk Factor for Poor Functional Outcome of Acute Ischemic Stroke

Background and Purpose:

The present study aims to evaluate the role of blood pressure variability (BPV) as a target therapeutic risk factor for poor outcome of ischemic stroke by finding the association between the two and by finding the population attributable risk (PAR) of BPV compared to other baseline outcome predictors.

Methods:

A prospective observational study was carried out at GMCH, Nagpur, India from January to June 2019 in 75 patients diagnosed with acute ischemic stroke. BP was recorded hourly for the first 24 hours of admission and base line factors were collected along with measurement of stroke severity. BPV was measured by index of average real-time variability (ARV) while discharge outcome was measured by Barthel Index.

Results:

36.5% of patients had poor outcome at discharge. A significant association was found between 24-hr ARV of systolic BP and poor outcome (P = 0.002, 95% CI = 2.22-23.5). Five factors were found to be independent outcome predictors on multiple logistic regression (OR, 95% CI): age (1.07, 1.03–1.10), NIHSS score (1.12, 1.04–1.27), on admission SBP (5.12, 4.01–16.23), on admission RBS (2.23, 1.92–6.49) and 24 Hr ARV-SBP (9.65, 3.02–20.1). The PAR of 24 hr ARV-SBP was 23.6%, second only to NIHSS score (26.4%).

Conclusions:

Reduction in BP variability might have a beneficial impact on the outcome of patients with acute ischemic stroke. There is further scope to explore optimum therapeutic strategies to minimize BPV in the management of acute ischemic stroke.

Increased blood pressure variability during the subacute phase of ischemic stroke is associated with poor functional outcomes at 3 months

Thus far, it is well known that increased blood pressure variability may exacerbate stroke outcomes. Blood pressure in the acute phase would be influenced by both reactive hypertension to stroke and intrinsic blood pressure reactivity. Thus, we aimed to evaluate the association between blood pressure variability and outcomes at 3 months using ambulatory blood pressure monitoring in ischemic stroke patients in the subacute phase after reactive hypertension subsided. We retrospectively examined 626 consecutive patients with acute ischemic stroke who underwent 24-hour ambulatory blood pressure monitoring during the subacute phase of stroke (median, 9 days from onset). The variability in blood pressure was evaluated by assessing the standard deviation and coefficient of variation of systolic and diastolic blood pressure. The primary outcome was functional status at 3 months. A poor outcome was defined as a modified Rankin scale score of 3 or more and a good outcome as 2 or less. We assessed the functional outcome at 3 months in 497 patients (79.4%). The mean systolic and diastolic blood pressure levels were not associated with functional outcome. The multivariable analysis revealed that increases in the standard deviations of systolic and diastolic blood pressure, coefficient of variation of diastolic blood pressure, and morning blood pressure surge were associated with poor outcome. Blood pressure variability during the subacute phase of ischemic stroke can be a useful prognostic indicator of poor functional outcome at 3 months in patients with acute ischemic stroke.

Effect of Glyceryl Trinitrate on Hemodynamics in Acute Stroke

Background and Purpose- Increased blood pressure (BP), heart rate, and their derivatives (variability, pulse pressure, rate-pressure product) are associated with poor clinical outcome in acute stroke. We assessed the effects of glyceryl trinitrate (GTN) on hemodynamic parameters and these on outcome in participants in the ENOS trial (Efficacy of Nitric Oxide in Stroke). Methods- Four thousand and eleven patients with acute stroke and raised BP were randomized within 48 hours of onset to transdermal GTN or no GTN for 7 days. Peripheral hemodynamics were measured at baseline (3 measures) and daily (2 measures) during treatment. Between-visit BP variability over days 1 to 7 (as SD) was assessed in quintiles. Functional outcome was assessed as modified Rankin Scale and cognition as telephone mini-mental state examination at day 90. Analyses were adjusted for baseline prognostic variables. Data are mean difference or odds ratios with 95% CI. Results- Increased baseline BP (diastolic, variability), heart rate, and rate-pressure product were each associated with unfavorable functional outcome at day 90. Increased between-visit systolic BP variability was associated with an unfavourable shift in modified Rankin Scale (highest quintile adjusted odds ratio, 1.65; 95% CI, 1.37-1.99), worse cognitive scores (telephone mini-mental state examination: highest quintile adjusted mean difference, -2.03; 95% CI, -2.84 to -1.22), and increased odds of death at day 90 (highest quintile adjusted odds ratio, 1.57; 95% CI, 1.12-2.19). GTN lowered BP and rate-pressure product and increased heart rate at day 1 and reduced between-visit systolic BP variability. Conclusions- Increased between-visit BP variability was associated with poor functional and cognitive outcomes and increased death 90 days after acute stroke. In addition to lowering BP and rate-pressure product, GTN reduced between-visit systolic BP variability. Agents that lower BP variability in acute stroke require further study.

Blood pressure variability estimated by ARV is a predictor of poor short-term outcomes in a prospective cohort of minor ischemic stroke

Prior studies have shown that patients with minor ischemic stroke have substantial disability rates at hospital discharge. We sought to determine whether blood pressure variability (BPV) estimated by average real variability (ARV) is one of the predictors of poor outcome at 90 days. Four hundred fifty-one consecutive patients with ischemic stroke treated within 7 days after onset were enrolled prospectively. Baseline magnetic resonance imaging (MRI) was performed on all subjects. Blood pressure was measured for all recruited patients every 2 hours in the first 24 hours after admission, followed by measurements collected every 4 hours from day 2 to day 7 after admission. ARV was used to estimate BPV. A total of 192 patients with minor ischemic stroke were enrolled, and 11 of them (5.7%) had poor outcomes. Univariate regression analysis showed that early neurological deterioration (X² = 21.44, P = 0.000), severe symptomatic large artery stenosis or occlusion (X² = 9.260, P = 0.000), large artery atherosclerotic stroke (X² = 7.14, P = 0.002), total cholesterol (TC), and D2-7 SBP-ARV (t = 5.449, P = 0.001) of the poor outcome group were significantly higher than those of the good outcome group. Multivariate logistic regression analysis showed that early neurological deterioration (OR 4.369, 95% CI 3.54, 15.65; P = 0.001), severe symptomatic large artery stenosis or occlusion (OR 5.56, 95% CI 3.56, 13.65; P = 0.000), large artery atherosclerotic stroke (OR 3.56, 95% CI 1.45, 7.48; P = 0.004), and D2-7 SBP-ARV (OR 3.96, 95% CI 1.90, 20.18, P = 0.008) were significantly related to poor outcomes. In conclusion, approximately 5.7% of minor ischemic stroke patients had poor outcomes. D2-7 SBP-ARV, early neurologic deterioration, severe symptomatic artery stenosis or occlusion, and large atherosclerotic stroke were the independent risk factors of poor short-term outcomes.

Blood Pressure Variability in Acute Ischemic Stroke: Influence of Infarct Location in the Insular Cortex

Background: The aim of this study was to elucidate the influence of insular infarction on blood pressure (BP) variability and outcomes according to the region of the insular cortex affected. Methods: A total of 90 patients diagnosed with acute unilateral ischemic stroke were registered. The BP variability was calculated over 24 h after admission (hyperacute) and for 2–3 days after admission (acute). Patients were classified into groups of right and left, and then right anterior, right posterior, left anterior, and left posterior insular infarction. Results: Patients with insular infarction showed a significantly larger infarct volume, higher modified Rankin scale scores, and lower SD and coefficient of variation (CV) of ­systolic BP in the hyperacute phase than shown by patients without insular infarction (p < 0.01, p < 0.01, p = 0.02, and p = 0.03, respectively). The SD and CV of systolic BP in the hyperacute phase showed significant differences among the 3 groups with right insular infarction, with left insular infarction, and without insular infarction (p < 0.05 and p < 0.05, respectively). There was a tendency for the systolic BP variability to be lower in patients with right anterior insular infarction than in patients with infarcts in other areas. Conclusion: The right insular cortex, especially the anterior part, might be a hub for autonomic nervous regulation.

Ambulatory blood pressure variability within the first 24 hours after admission and outcomes of acute ischemic stroke

Our purpose was to evaluate the value of blood pressure variability within the first 24 hours after admission in predicting outcomes of patients with acute ischemic stroke (AIS). A greater variability in systolic blood pressure (adjusted odds ratio [OR] = 1.801, 95% confidence interval [CI] = 1.167-2.779) was associated with poor discharge outcome, especially for nondiabetics (adjusted OR = 1.948, 95% CI = 1.184-3.205) and cardioembolism-related patients with AIS (OR = 7.650, 95% CI = 1.370-42.713). However, this correlation was not observed with a long-term (3-month or 6-month) outcome in patients with AIS. There was no association between diastolic blood pressure variability within the first 24 hours after admission and outcome. In conclusion, systolic blood pressure variability within the first 24 hours after admission is a critical predictor for short-term outcome of patients with AIS.

Systolic Blood Pressure Within 24 Hours After Thrombectomy for Acute Ischemic Stroke Correlates With Outcome

Background

Current guidelines suggest treating blood pressure above 180/105 mm Hg during the first 24 hours in patients with acute ischemic stroke undergoing any form of recanalization therapy. Currently, no studies exist to guide blood pressure management in patients with stroke treated specifically with mechanical thrombectomy. We aimed to determine the association between blood pressure parameters within the first 24 hours after mechanical thrombectomy and patient outcomes.

Methods and Results

We retrospectively studied a consecutive sample of adult patients who underwent mechanical thrombectomy for acute ischemic stroke of the anterior cerebral circulation at 3 institutions from March 2015 to October 2016. We collected the values of maximum, minimum, and average values of systolic blood pressure, diastolic blood pressure, and mean arterial pressures in the first 24 hours after mechanical thrombectomy. Primary and secondary outcomes were patients’ functional status at 90 days measured on the modified Rankin scale and the incidence and severity of intracranial hemorrhages within 48 hours. Associations were explored using an ordered multivariable logistic regression analyses. A total of 228 patients were included (mean age 65.8±14.3; 104 males, 45.6%). Maximum systolic blood pressure independently correlated with a worse 90‐day modified Rankin scale and hemorrhagic complications within 48 hours (adjusted odds ratio=1.02 [1.01–1.03], P=0.004; 1.02 [1.01–1.04], P=0.002; respectively) in multivariable analyses, after adjusting for several possible confounders.

Conclusions

Higher peak values of systolic blood pressure independently correlated with worse 90‐day modified Rankin scale and a higher rate of hemorrhagic complications. Further prospective studies are warranted to identify whether systolic blood pressure is a therapeutic target to improve outcomes.

Predictive Significance of Day-to-Day Blood Pressure Variability in Acute Ischemic Stroke for 12-Month Functional Outcomes

BACKGROUND

Previous studies on the association between blood pressure (BP) variability in acute ischemic stroke and functional outcomes have yielded conflicting results. We aimed to investigate the predictive significance of day-to-day BP variability during the 7 days following stroke onset for functional outcomes at 12 months.

METHODS

A total of 229 patients (male 68.8%, mean age 66.7 ± 13.0 years) within 24 hours after onset were prospectively studied. The first 24 hours and day-to-day BP variability, including the SD, coefficient variation (CV), average real variation, and ΔBP (difference between the maximum and minimum BP), were derived and compared to functional outcomes. The functional outcomes were accessed using the baseline severity-adjusted analysis at 12 months post-stroke.

RESULTS

The patients with poor outcomes at 12 months had significantly higher morning systolic BP (SBP; 1-3 days after onset) than those with good outcomes. The day-to-day SBP variability parameters (1-7 days) such as SD, CV, and Δ SBP were significantly higher in the patients with poor outcomes than in those with good outcomes (17.0 ± 6.0 vs. 14.8 ± 5.3 mm Hg, 11.8 ± 3.9 vs. 10.6 ± 3.5, 48.3 ± 17.7 vs. 39.9 ± 15.5 mm Hg, respectively; P < 0.05). After adjustment for demographic and clinical features, day-to-day Δ SBP was associated with poorer functional outcomes at 12 months (odds ratio, 95% confidence interval: 1.547, 1.097-2.181). Even after adjusting for the mean SBP, Δ SBP was independently associated with 12-month poor functional outcomes (odds ratio, 95% confidence interval: 1.577, 1.095-2.272).

CONCLUSIONS

Day-to-day SBP variability in acute ischemic stroke was associated with poor functional outcomes at 12 months.

CLINICAL TRIALS REGISTRATION

Trial Number NCT02675972.

Short-term blood pressure variability and long-term blood pressure variability: which one is a reliable predictor for recurrent stroke

The relationship between blood pressure variability (BPV) and stroke recurrence is controversial. This study aimed to evaluate the predictive value of short-term and long-term BPV for stroke recurrence. The data from blood pressure and clinical outcome in TIA or ischemic stroke (BOSS) study included participants with acute ischemic stroke or transient ischemic attack (TIA) within 7 days after onset. Short-term BPV was measured by 24-h ambulatory BP measurement during hospitalisation. Long-term BPV, based on home blood pressure measurement, was measured by patients or their families from discharge to 90 days after qualifying events onset (twice daily). Variability for systolic blood pressure (SBP) was assessed as the s.d., coefficients of variance (CV). The clinical outcome was recurrent stroke within 1 year. Cox proportional hazards models were used to test the association of short-term BPV, long-term BPV and stroke recurrence. Among 1764 participants, the mean age was 62.45±10.99 years, and 32.1% were females, during 1-year follow-up, 106 (6.0%) participants experienced recurrent stroke. Indices of long-term BPV were significantly associated with stroke recurrence (s.d.: adjusted HR: 1.939, 95% CI: 1.122-3.351; CV: adjusted HR 1.955, 95% CI: 1.174-3.255), independent of mean SBP. However, all indices of short-term BPV (s.d., CV) were not associated with stroke recurrence (s.d.: adjusted HR: 1.245, 95% CI: 0.680-2.280; CV: adjusted HR: 1.142, 95% CI: 0.640-2.038). In conclusion, long-term variation of SBP is a better predictor than short-term variation of SBP for recurrent stroke after acute ischemic stroke or TIA.

Peak Systolic Velocity Measured by Continuous-Wave Doppler Ultrasonography without Angle Correction in Patients with Internal Carotid Artery Stenosis

BACKGROUND

Peak systolic velocity (PSV) is measured with pulse-wave (PW) Doppler with angle correction in patients with internal carotid artery stenosis (ICAS). However, the correlation between conventional angiography and PSV shows considerable scattering. We hypothesized that measuring PSV without angle correction would lead to better inter-rater reliability. This hypothesis was tested using a sector probe and continuous-wave (CW) Doppler without angle correction.

METHODS

Consecutive patients with more than 50% ICAS were enrolled from a prospective database. PSV was measured with PW Doppler with angle correction (PW PSV) and CW Doppler without angle correction (CW PSV) by 2 examiners. The inter-rater reliabilities of PW PSV and CW PSV were analyzed by Spearman's rank correlation test.

RESULTS

A total of 37 ICAS sites (median 67 [interquartile range 57-78] % stenosis) were enrolled. Measuring PSV using a sector probe insonating nearly parallel to the flow was feasible in all cases. Inter-rater reproducibility of CW PSV (Spearman's ρ = .810) was similar to that of PW PSV (Spearman's ρ = .796). When limited to patients with a PSV greater than 200 cm/s with both PW Doppler examinations (25 ICAS sites), inter-rater reliability was relatively higher for CW PSV (Spearman's ρ = .674) than for PW PSV (Spearman's ρ = .423).

CONCLUSIONS

Measuring PSV with CW Doppler using a sector probe was feasible. Inter-rater reliability was similar between PW Doppler with angle correction and CW Doppler without angle correction in evaluating PSV in patients with ICAS. CW Doppler appears to have better inter-rater reproducibility than PW Doppler in assessing high PSV.

Prognostic Significance of Short-Term Blood Pressure Variability in Acute Stroke

Background and Purpose—

Blood pressure variability (BPV) may be an important prognostic factor acutely after stroke. This review investigated the existing evidence for the effect of BPV on outcome after stroke, also considering BPV measurement techniques and definitions.

Methods—

A literature search was performed according to a prespecified study protocol. Two reviewers independently assessed study eligibility and quality. Where appropriate, meta-analyses were performed to assess the effect of BPV on poor functional outcome.

Results—

Eighteen studies from 1359 identified citations were included. Seven studies were included in a meta-analysis for the effect of BPV on functional outcome (death or disability). Systolic BPV was significantly associated with poor functional outcome: pooled odds ratio per 10-mm Hg increment, 1.2; confidence interval (1.1–1.3). A descriptive review of included studies also supports these findings, and in addition, it suggests that systolic BPV may be associated with increased risk of intracranial hemorrhage in those treated with thrombolytic therapy.

Conclusions—

This systematic review and meta-analysis suggest that greater systolic BPV, measured early from ischemic stroke or intracerebral hemorrhage onset, is associated with poor longer-term functional outcome. Future prospective studies should investigate how best to measure and define BPV in acute stroke, as well as to determine its prognostic significance.

Prognostic Value of 24-H ABPM in Acute Ischemic Stroke for Short-, Medium-, and Long-Term Outcome: A Systematic Review and Meta-Analysis

Background

The association of blood pressure levels during the acute phase of ischemic stroke with outcome remains controversial.

Aims

The objective of this systematic review is to assess the predictive value for stroke outcome assessed by the modified Rankin scale score of systolic and diastolic blood pressure, measured by ambulatory blood pressure monitoring methods during the acute phase of ischemic stroke, compared with the values of casually derived blood pressure measurement on admission.

Methods

We searched for studies with patients admitted within 24 h of stroke onset, and who had ambulatory blood pressure monitoring during the first 24 h of admission. We identified studies that reported blood pressure in those with good outcome and in those with poor outcome at end of follow-up, and performed a meta-analysis of the effect of mean blood pressure on outcome.

Results

High systolic and diastolic blood pressure levels derived with ambulatory blood pressure monitoring were associated with poor short-, medium-, and long-term outcome, but the same was not found for casual blood pressure measurements. An increase in systolic blood pressure of 9·1 mmHg (95% confidence interval: 6·6–11·6, P < 0·001; I2 = 9%) and an increase in diastolic blood pressure of 2·3 mmHg (95% confidence interval: 0·8–3·7, P = 0·002; I2 = 0%) were associated with poor outcome.

Conclusions

Higher systolic and diastolic blood pressure levels derived with ambulatory blood pressure monitoring were associated with poor outcome. The same was not found for higher casual blood pressure measurements on admission, and it is possible that ambulatory blood pressure monitoring conveys better prognostic information.

Short-Term Blood Pressure Variability in Acute Stroke

Background and Purpose—

Short-term blood pressure variability (BPV) may predict outcome in acute stroke. We undertook a post hoc analysis of data from 2 randomized controlled trials to determine the effect of short-term BPV on 2-week outcome.

Methods—

Controlling Hypertension and Hypotension Immediately Post Stroke (CHHIPS) was a trial of BP-lowering, enrolling 179 acute stroke patients (onset <36 hours). Continue or Stop Post-Stroke Antihypertensives Collaborative Study (COSSACS) compared a strategy of continuation versus temporarily stopping prestroke antihypertensive therapy in 763 acute stroke patients (onset <48 hours). BPV at baseline (defined as SD, coefficient of variation, variation independent of the mean, and average real variability) was derived from standardized casual cuff BP measures (6 readings <30 minutes). Adjusted logistic regression models were used to assess the relation between BPV and death and disability (modified Rankin scale>3) at 2 weeks.

Results—

Seven hundred six (92.5%) and 171 (95.5%) participants were included in the analysis for the COSSACS and CHHIPS data sets, respectively. Adjusted logistic regression analyses revealed no statistically significant associations between any of the included BPV parameters with 2-week death or disability in either study data set: COSSACS, odds ratio SD systolic BP 0.98 (0.78–1.23); CHHIPS, odds ratio SD systolic BP 0.97 (0.90–1.11).

Conclusions—

When derived from casual cuff BP measures, short-term BPV is not a useful predictor of early (2 weeks) outcome after acute stroke. Differing methodology may account for the discordance with previous studies indicating long-term (casual BPV) and short-term (beat-to-beat BPV) prognostic value.

Clinical Trial Registration—

COSSACS was registered on the International Standard Randomised Controlled Trial Register; URL: http://www.isrctn.com . Unique identifier: ISRCTN89712435. CHHIPS was registered on the National Research Register; URL: http://public.ukcrn.org.uk . Unique identifier: N0484128008.

Effects of different classes of antihypertensive agents on the outcome of acute ischemic stroke

It is unclear whether antihypertensive treatment before stroke affects acute ischemic stroke severity and outcome. To evaluate this association, the authors studied 482 consecutive patients (age 78.8±6.7 years) admitted with acute ischemic stroke. Stroke severity was assessed at admission with the National Institutes of Health Stroke Scale (NIHSS). The outcome was assessed with rates of adverse outcome (modified Rankin scale at discharge ≥2). Independent predictors of severe stroke (NIHSS ≥16) were female sex and atrial fibrillation. Treatment with diuretics before stroke was associated with nonsevere stroke. At discharge, patients with adverse outcome were less likely to be treated before stroke with β-blockers or with diuretics. Independent predictors of adverse outcome were older age, higher NIHSS at admission, and history of ischemic stroke. Treatment with diuretics before stroke appears to be associated with less severe neurologic deficit in patients with acute ischemic stroke.

Complexity of heart rate variability predicts outcome in intensive care unit admitted patients with acute stroke

BACKGROUND

Heart rate variability (HRV) has been proposed as a predictor of acute stroke outcome. This study aimed to evaluate the predictive value of a novel non-linear method for analysis of HRV, multiscale entropy (MSE) and outcome of patients with acute stroke who had been admitted to the intensive care unit (ICU).

METHODS

The MSE of HRV was analysed from 1 h continuous ECG signals in ICU-admitted patients with acute stroke and controls. The complexity index was defined as the area under the MSE curve (scale 1-20). A favourable outcome was defined as modified Rankin scale 0-2 at 3 months after stroke.

RESULTS

The trends of MSE curves in patients with atrial fibrillation (AF) (n=77) were apparently different from those in patients with non-AF stroke (n=150) and controls (n=60). In addition, the values of complexity index were significantly lower in the patients with non-AF stroke than in the controls (25.8±.3 vs. 32.3±4.3, p<0.001). After adjustment for clinical variables, patients without AF who had a favourable outcome were significantly related to higher complexity index values (OR=1.15, 95% CI 1.07 to 1.25, p<0.001). Importantly, the area under the receiver operating characteristic curve for predicting a favourable outcome of patients with non-AF stroke from clinical parameters was 0.858 (95% CI 0.797 to 0.919) and significantly improved to 0.903 (95% CI 0.853 to 0.954) after adding on the parameter of complexity index values (p=0.020).

CONCLUSIONS

In ICU-admitted patients with acute stroke, early assessment of the complexity of HRV by MSE can help in predicting outcomes in patients without AF.

Association of ambulatory blood pressure and heart rate with advanced white matter lesions in ischemic stroke patients

BACKGROUND

White matter lesions (WMLs) are a common finding in stroke patients, and the most important risk factors are old age and hypertension. Although many studies have described the association between WMLs and ambulatory blood pressure monitoring (ABPM) parameters in healthy subjects and hypertensive patients, little is known about the association in hypertensive ischemic stroke patients.

METHODS

From July 2009 to June 2012, 169 consecutive hypertensive noncardioembolic ischemic stroke patients were recruited within 1 week of suffering a stroke, and ABPM was applied 1 or 2 weeks after stroke onset. The subjects were classified into 2 groups according to the presence of advanced WMLs, and their ABPM parameters were compared. Finally, multivariable logistic regression analyses were performed to investigate the independent relationships between WMLs and ABPM parameters.

RESULTS

Seventy (41%) patients had advanced WMLs. In univariable analysis, higher 24-hour, awake, and asleep systolic blood pressure (SBP)/diastolic blood pressure levels and 24-hour pulse pressure were associated with advanced WMLs. However, circadian blood pressure parameters such as 24-hour BP variability, morning surge, and nocturnal dipping pattern were not associated with advanced WMLs. After adjustments, old age (odds ratio (OR) = 1.063; 95% confidence interval (CI) = 1.024-1.104; P = 0.002), high 24-hour SBP levels (OR = 1.055; 95% CI = 1.028-1.082; P < 0.001), and high 24-hour heart rate (OR = 1.041; 95% CI = 1.006-1.078; P = 0.023) were independently associated with advanced WMLs.

CONCLUSIONS

In addition to old age and elevated 24-hour SBP, increased heart rate is associated with advanced WMLs in ischemic stroke patients. Heart rate deserves more attention in predicting advanced WMLs in those patients.

Ambulatory blood pressure in stroke and cognitive dysfunction

We have reviewed the most relevant data regarding ABPM and brain damage, with specific reference to first and recurrent stroke, silent structural brain lesions such as lacunar infarcts and white matter lesions, and cognitive impairment. Only two large studies have evaluated the usefulness of ABPM in relation to antihypertensive treatment in primary stroke prevention. In the Syst-Eur trial, drug treatment reduced ABPM and office BP more than placebo in patients with sustained isolated systolic hypertension (ISH). In contrast, in those patients with white-coat hypertension (WCH) changes in ABPM between the treatment groups were not significantly different. Patients with WCH had a lower incidence of stroke (p < 0.05) during follow-up than patients with sustained ISH, suggesting that WCH is a benign condition. In the HYVET trial 50 % of the very elderly patients included with office systolic BP > 160 mmHg had WCH. However, a significant 30 % stroke reduction was observed in treated patients including those with WCH, indicating that WCH may not be a benign condition in the elderly. In the acute stroke setting, where treatment of hypertension is not routinely recommended due to the lack of evidence and the differing results of the very few available trials, ABPM data shows that sustained high BP during the first 24 h after acute stroke is related to the formation of cerebral edema and a poorer functional status. On the other hand, even when nondipping status was initially related to a poorer prognosis, data indicate that patients with very-large nocturnal dipping, the so-called "extreme dippers", are those with the worse outcomes after stroke. The association between different ABPM parameters (circadian pattern, short-term variability) and poorer performance scores in cognitive function tests have been reported, especially in elderly hypertensives. Unfortunately most of these studies were cross-sectional and the associations do not establish causality.

Impact of Early Blood Pressure Variability on Stroke Outcomes After Thrombolysis

Background and Purpose—

The present study determines associations between early blood pressure (BP) variability and stroke outcomes after intravenous thrombolysis.

Methods—

In 527 stroke patients receiving intravenous alteplase (0.6 mg/kg), BP was measured 8 times within the first 25 hours. BP variability was determined as ΔBP (maximum-minimum), standard deviation (SD), coefficient of variation, and successive variation.

Results—

The systolic BP course was lower among patients with modified Rankin Scale (mRS) 0 to 1 than those without ( P <0.001). Most of systolic BP variability profiles were significantly associated with outcomes. Adjusted odds ratios (95% confidence interval) per 10 mm Hg (or 10% for coefficient of variation) on symptomatic intracerebral hemorrhage were as follows: ΔBP, 1.33 (1.08–1.66); SD, 2.52 (1.26–5.12); coefficient of variation, 3.15 (1.12–8.84); and successive variation, 1.82 (1.04–3.10). The respective values were 0.88 (0.77–0.99), 0.73 (0.48–1.09), 0.77 (0.43–1.34), and 0.76 (0.56–1.03) for 3-month mRS 0 to 1; and 1.40 (1.14–1.75), 2.85 (1.47–5.65), 4.67 (1.78–12.6), and 1.99 (1.20–3.25) for death. Initial BP values before thrombolysis were not associated with any outcomes.

Conclusions—

Early systolic BP variability was positively associated with symptomatic intracerebral hemorrhage and death after intravenous thrombolysis.