Pulse pressure variability is associated with unfavorable outcomes in acute ischaemic stroke patients treated with intravenous thrombolysis

Neuromodulation with Ultrasound: Hypotheses on the Directionality of Effects and a Community Resource

Low-intensity Transcranial Ultrasound Stimulation (TUS) is a promising non-invasive technique for deep-brain stimulation and focal neuromodulation. Research with animal models and computational modelling has raised the possibility that TUS can be biased towards enhancing or suppressing neural function. Here, we first conduct a systematic review of human TUS studies for perturbing neural function and alleviating brain disorders. We then collate a set of hypotheses on the directionality of TUS effects and conduct an initial meta-analysis on the human TUS study reported outcomes to date (n = 32 studies, 37 experiments). We find that parameters such as the duty cycle show some predictability regarding whether the targeted area's function is likely to be enhanced or suppressed. Given that human TUS sample sizes are exponentially increasing, we recognize that results can stabilize or change as further studies are reported. Therefore, we conclude by establishing an Iowa-Newcastle (inTUS) resource for the systematic reporting of TUS parameters and outcomes to support further hypothesis testing for greater precision in brain stimulation and neuromodulation with TUS.

Blood Pressure Variability in Acute Stroke: A Narrative Review

The management of blood pressure variability (BPV) in acute stroke presents a complex challenge with profound implications for patient outcomes. This narrative review examines the role of BPV across various stages of acute stroke care, highlighting its impact on treatment strategies and prognostic considerations. In the prehospital setting, while guidelines lack specific recommendations for BP management, emerging evidence suggests a potential link between BPV and outcomes. Among ischaemic stroke patients who are ineligible for reperfusion therapies, BPV independently influences functional outcomes, emphasising the need for individualised approaches to BP control. During intravenous thrombolysis and endovascular therapy, the intricate interplay between BP levels, recanalisation status, and BPV is evident. Striking a balance between aggressive BP lowering and avoiding hypoperfusion-related complications is essential. Intracerebral haemorrhage management is further complicated by BPV, which emerges as a predictor of mortality and disability, necessitating nuanced BP management strategies. Finally, among patients with acute subarachnoid haemorrhage, increased BPV may be correlated with a rebleeding risk and worse outcomes, emphasizing the need for BPV monitoring in this population. Integration of BPV assessment into clinical practice and research protocols is crucial for refining treatment strategies that are tailored to individual patient needs. Future studies should explore novel interventions targeting BPV modulation to optimise stroke care outcomes.

The impact of blood pressure variability on the development of parenchymal hematoma in acute cerebral infarction with atrial fibrillation

Although blood pressure variability (BPV) and reperfusion are associated with parenchymal hematoma (PH) after stroke, the relationship between BPV and PH in atrial fibrillation (AF) patients who are at risk of reperfusion injury with frequent spontaneous recanalization is unknown. This study aimed to investigate whether BPV within the first 48 h is associated with PH within 72 h in patients with AF and stroke in terms of major vessel occlusion status. A total of 131 patients with AF that were admitted within 24 h after stroke onset were enrolled. PH was defined as a confluent hemorrhage with mass effect. The maximum (max), minimum (min), and average blood pressure (BP) during the first 48 h after admission were calculated. BPV was analyzed by using range between maximum and minimum (max-min), successive variation (SV), standard deviation (SD), and coefficient of variation (CV). All parameters were applied for systemic (SBP), diastolic (DBP), and pulse pressure (PP). After adjusting for confounding variables, various BPV parameters were associated with PH, including SBPmax (p = 0.0426), SBPSV (p = 0.0006), DBPmax-min (p = 0.0437), DBPSV (p = 0.0358), DBPSD (p = 0.0393), PPmax-min (p = 0.0478), PPSV (p < 0.0001), PPSD (p = 0.0034), and PPCV (p = 0.0120). The relationship remained significant in patients with a patent major vessel responsible for infarction but not in patients with an occluded major vessel. In conclusion, this study revealed that high BPV was associated with PH in patients with AF and acute stroke, particularly for those with a patent major vessel. The control of BP and BPV after stroke may be considered in patients with AF.

Association of Pulse Pressure Fluctuation During Hospitalization With Adverse Outcomes Within 3 Months After Ischemic Stroke

BACKGROUND

Pulse pressure (PP) depends on heart function and arterial wall elasticity, which is closely related to the incidence of ischemic stroke. However, the association of PP fluctuation during hospitalization with adverse outcomes after ischemic stroke remains unclear.

METHODS

The present study included 3,971 patients with ischemic stroke. The primary outcome was the composite outcome of death or vascular events within 3 months after ischemic stroke. PP fluctuation was reflected by successive variation of PP (PP-SV).

RESULTS

The cumulative incidence rates of the primary outcome were the highest in the patients in the highest quartiles of PP-SV (P < 0.05). The multivariable-adjusted hazard ratios (95% confidence intervals) of the primary outcome in the highest quartiles were 1.86 (1.03-3.38) for death or vascular events, and 2.15 (1.06-4.37) for vascular events (all Ptrend < 0.05). Multivariable-adjusted restricted cubic spline analyses showed linear associations of PP-SV during hospitalization with the primary outcome (P for linearity <0.05).

CONCLUSIONS

Large PP fluctuation during hospitalization was associated with increased risks of adverse outcomes within 3 months after ischemic stroke, which provided valuable new insight for blood pressure management in the acute phase of ischemic stroke. Controlling PP fluctuation may be contributing to improving prognosis after ischemic stroke.

Significance of pulse pressure variability in predicting functional outcome in acute ischemic stroke: a retrospective, single-center, observational cohort study

This study aimed to determine the association between pulse pressure variability (PPV) and short- and long-term outcomes of acute ischemic stroke (AIS) patients. We studied 203 tertiary stroke center patients with AIS. PPV during 72 h after admission was analyzed using different variability parameters including standard deviation (SD). Patients' outcome was assessed after 30 and 90 days post-stroke with modified Rankin Scale. The association between PPV and outcome was investigated using logistic regression analysis with adjustment for potential confounders. The predictive significance of PPV parameters was determined using area under the curve (AUC) of receiver operating characteristics. In the unadjusted logistic regression analysis, all PPV indicators were independently associated with unfavorable outcome at 30 days (i.a. Odds ratio (OR) = 4.817, 95%CI 2.283-10.162 per 10 mmHg increase in SD, p = 0.000) and 90 days (i.a. OR = 4.248, 95%CI 2.044-8.831 per 10 mmHg increase in SD, p = 0.000). After adjustment for confounders, ORs for all PPV indicators remained statistically significant. On the basis of AUC values, all PPV parameters were found relevant outcome predictors (p < 0.01). In conclusion, elevated PPV during first 72 h after admission due to AIS is associated with unfavorable outcome at 30 and 90 days, independent of mean blood pressure levels.

Detrimental effect of increased blood pressure variability on clinical outcome in acute ischemic stroke treated with reperfusion therapy: a case control study

Background

Blood pressure variability (BPV) is related to clinical outcome in acute ischemic stroke (AIS) treated with reperfusion therapy, but still is not included in clinical practice. This study aims to associate BPV during the first week of AIS with the outcome at three months.

Methods

We included 236 AIS patients treated with reperfusion therapy, and then divided them into good outcome and poor outcome groups. BPV measurements, including standard deviation, coefficient of variation, average real variability (ARV), and range, were recorded at stages of 2 h, 24 h, and 7 days after reperfusion therapy, respectively. These measurements were compared between the two groups. Then, ROC curve analysis examined the ability of BPV measurements in differentiating good and poor outcome groups; logistic regression analysis detected variables associated with clinical outcome in all subjects.

Results

The good outcome group exhibited significantly less BPV at all stages relative to the poor outcome group. The BPV measurements exhibited the potential to differentiate the two groups by the ROC curve analysis, especially for those at the 24-h stage. Higher ARV of diastolic BP and higher range of systolic BP at the 24-h stage, together with greater disease severity at baseline, were associated with poor clinical outcome.

Conclusions

Greater BPV during the first week of AIS is associated with poor outcome for the patients treated with reperfusion therapy. The BPV measurements play an important role in modulating clinical outcome, and have the potential to be included in future AIS guidelines.

The Updated Role of Transcranial Ultrasound Neuromodulation in Ischemic Stroke: From Clinical and Basic Research

Ischemic stroke is a common cause of death and disability worldwide, which leads to serious neurological and physical dysfunction and results in heavy economic and social burdens. For now, timely and effective dissolution of thrombus, and ultimately improvement in the recovery of neurological functions, is the treatment strategy focus. Recently, many studies have reported that transcranial ultrasound stimulation (TUS), as a non-invasive method, can dissolve thrombus, improve cerebral blood circulation, and exert a neuroprotective effect post-stroke. TUS can promote functional recovery and improve rehabilitation efficacy among patients with ischemic stroke. This mini-review summarizes the potential mechanism and limitation of TUS in stroke aims to provide a new strategy for the future treatment of patients with ischemic stroke.

Increased Pulse Pressure Variability Within the First 24 Hours Leads to Poor Disposition in Subarachnoid Hemorrhage Patients

BACKGROUND

Aneurysmal subarachnoid hemorrhage (SAH) continues to be associated with significant morbidity and mortality despite treatment advancements. Although high blood pressure (BP) remains a significant risk factor in aneurysmal SAH and rerupture, the role of BP parameters and fluctuation in prognostication remains unclear. We sought to define how BP parameters and variability within 24 hours of hospitalization in acute-onset SAH affects patient discharge outcomes.

METHODS

We retrospectively analyzed a prospectively collected cohort of SAH patients. Hourly BP parameters, including systolic BP (SBP), diastolic BP, pulse pressure (PP), and their corresponding variability (delineated by SD), were collected to investigate associations with the primary endpoint of discharge disposition.

RESULTS

One hundred and seventy-four SAH patients were included in the study. On bivariate analysis, Hunt-Hess (HH) score, Fisher grade, intraventricular hemorrhage, external ventricular drain placement, and SBP and PP variability were significantly associated with a poor disposition. Poor disposition was significantly associated with age, HH score, intraventricular hemorrhage, and PP variability on multivariate analysis. PP variability remained an independent predictor for poor disposition (odds ratio 1.11, 95% confidence interval, 1.02-1.21, P = 0.02) when adjusting for potential confounders.

CONCLUSIONS

Increased BP and PP variability within the first 24 hours of admission portends a poor discharge disposition for aneurysmal SAH patients.

Blood pressure variability and outcomes after mechanical thrombectomy based on the recanalization and collateral status

BACKGROUND

Blood pressure (BP), recanalization status, and collateral circulation are important factors for cerebral autoregulation after stroke. We aimed to investigate the association of various BP variability (BPV) parameters with clinical outcomes after mechanical thrombectomy (MT) according to recanalization and collateral status.

METHODS

We included 502 consecutive patients who underwent MT due to anterior circulation large vessel occlusion stroke at three comprehensive stroke centers. BPV parameters were standard deviation (SD), maximum/minimum BP, coefficient of variation (CV) and successive variation (SV). The clinical outcomes included 90-day functional outcome assessed by modified Rankin Scale score and symptomatic intracranial hemorrhage (sICH).

RESULTS

Among the included patients, 219 (43.6%) achieved good functional outcomes and 59 (11.8%) developed sICH. After adjusting for confounders, higher systolic BP (SBP) variability [CV (odds ratio (OR), 1.089, p = 0.035), SV (OR, 1.082, p = 0.004). and SD (OR, 1.074, p = 0.027)] was associated with a lower likelihood of a favorable outcome. In addition, higher SBP [CV (OR, 1.156, p = 0.001) and SD (OR, 1.118, p = 0.001)] were significantly associated with increased odds of sICH. Moreover, the relationship between BPV and the outcomes depended on recanalization status. However, regardless of collateral status, a higher BPV after MT was associated with worse outcomes.

CONCLUSIONS

Higher SBP SD and CV during the first 24 h after MT was a powerful predictor of worse clinical outcomes, regardless of the collateral status. However, the effects of BPV on outcomes were more substantial among patients with successful reperfusion.