Optimal Blood Pressure Targets in the Early Stage of Cardioembolic Ischemic Stroke

Article information

J Stroke. 2025;27(3):430-433

Publication date (electronic) : 2025 September 29

doi : https://doi.org/10.5853/jos.2025.01592

Hyunsoo Kim, Joon-Tae Kim, Kang-Ho Choi, Seung Hyun Min, Jae-Myung Kim, Man-Seok Park

Department of Neurology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea

Correspondence: Man-Seok Park Department of Neurology, Chonnam National University Medical School, Chonnam National University Hospital, 42 Jebong-ro, Dong-gu, Gwangju 61469, Korea Tel: +82-62-220-6142 E-mail: mspark@jnu.ac.kr

Received 2025 April 4; Revised 2025 July 1; Accepted 2025 July 8.

Dear Sir:

The target blood pressure (BP) in acute ischemic stroke remains a topic of ongoing debate. Although elevated BP in the hyperacute phase is generally considered as compensatory, maintaining perfusion to the ischemic penumbra, several studies have shown that aggressive BP reduction within 48–72 hours may lead to adverse outcomes [1,2]. Based on these findings, current guidelines recommend against intensive BP lowering early after stroke onset [3]. However, most of these recommendations are based on studies involving heterogeneous stroke mechanisms, and the optimal BP targets may vary depending on the stroke subtype.

Cardioembolic stroke (CES) is pathophysiologically distinct from other ischemic subtypes, such as large artery atherosclerosis or lacunes [4]. CES typically involves sudden occlusion of large vessels, poorer collateral circulation, and an increased risk of hemorrhagic transformation (HT) and cerebral edema [5,6]. These characteristics may render patients with CES particularly vulnerable to elevated BP and less likely to benefit from permissive hypertension strategies designed for other subtypes. Despite its clinical significance, the CES-specific evidence for BP management remains limited.

To clarify the relationship between early BP and CES outcomes, we conducted a retrospective study at a tertiary stroke center between January 2011 and December 2023. We identified 2,441 individuals diagnosed with CES who were admitted within 48 hours of symptom onset. All patients had ≥24 systolic BP measurements taken during the first 48 hours of hospitalization using non-invasive monitors operated by trained staff.

Patients were grouped by mean systolic BP over 48 hours: normotensive (<140 mm Hg) and hypertensive (≥140 mm Hg), in line with the current clinical guidelines for hypertension. In addition, we calculated BP variability (BPV) indices—standard deviation (SD), average real variability (ARV), successive variation (SV), and coefficient of variation (CV)—and divided them into quartiles. The primary outcomes were early neurological deterioration (END) and favorable 3-month functional outcomes (modified Rankin Scale [mRS], 0–2). The secondary outcomes included HT, symptomatic intracranial hemorrhage (sICH), composite vascular events, and mortality. The detailed methodology is provided in the Supplementary Methods.

Among the 2,441 patients with CES (mean age 73.6 years, 50.5% male), 1,565 (64.1%) were normotensive and 876 (35.9%) were hypertensive. The general characteristics are presented in Supplementary Table 1. The hypertensive group had significantly higher rates of END (23.8% vs. 14.9%) and lower rates of favorable 3-month functional outcomes (41.1% vs. 53.4%) than the normotensive group (Supplementary Table 2). After adjusting for predefined variables, hypertensive group remained independently associated with both increased risk of END (adjusted odds ratio [OR] 1.49, 95% confidence interval [CI] 1.18–1.87, P=0.001) and lower odds of functional independence at 3 months (adjusted OR 0.76, 95% CI 0.61–0.94, P=0.013) (Table 1). Restricted cubic spline analysis revealed a nonlinear association between BP and prognosis. The optimal BP for favorable outcomes was approximately 122.9 mm Hg, suggesting a U-shaped relationship (Figure 1). Supplementary Figure 1 presents the mRS distribution and shift analysis according to BP groups. Although sICH and HT occurred more frequently in the hypertensive group, the difference was not statistically significant. However, patients with a higher BP had significantly increased rates of composite vascular events (adjusted OR 1.54, P=0.013) and mortality (adjusted OR 1.66, P=0.002) (Table 1). The findings related to the vascular outcomes are presented in Supplementary Table 3 and Supplementary Figure 2.

Table 1.

Primary outcomes according to mean sBP within 48 hours of stroke onset

Figure 1.

Restricted cubic splines for (A) favorable mRS (0–2) at 3-month and (B) END according to mean sBP. Adjusted variables: sex, age, BMI, initial NIHSS score, previous mRS score, history of anticoagulation, history of antiplatelet treatment, history of diabetic treatment, history of hypertension treatment, history of hypertension, history of diabetes, history of dyslipidemia, history of statin treatment, acute thrombolytic treatment, LDL-C, fasting glucose, and HbA1c. mRS, modified Rankin Scale; END, early neurological deterioration; sBP, systolic blood pressure; BMI, body mass index; NIHSS, National Institutes of Health Stroke Scale; LDL-C, low-density lipoprotein cholesterol; HbA1c, glycated hemoglobin; OR, odds ratio; CI, confidence interval.

Regarding BPV, higher SD and SV values were significantly associated with an increased risk of END. Patients in the highest SD quartile had a 54% higher risk of END than those in the lowest quartile (adjusted OR 1.54, P=0.013), with similar findings for SV (adjusted OR 1.66, P=0.002). A modest association was observed between higher SD and decreased likelihood of good functional outcomes, although statistical significance was attenuated in the highest quartile (Table 2).

Table 2.

Primary outcome according to quartiles of the BP variables

Several observational studies have evaluated the prognostic impact of BP levels specifically in CES patients, providing insight into stroke subtype-specific hemodynamic vulnerabilities [7]. In a study examining prognostic associations of BP according to stroke subtypes, BP had limited impact in lacunar and atherosclerotic strokes, whereas higher BP was associated with poor outcomes in CES [8]. Another study, which examined outcomes in relation to both admission and follow-up BP levels, reported that systolic BP ≥180 mm Hg was associated with poorer outcomes in CES patients and that reducing BPV improved prognosis [9]. Although few studies have focused specifically on BPV in CES, one analysis suggested that CES may exhibit distinct hemodynamic responses, including blunted BPV compared to other subtypes [10]. Collectively, these findings suggest that CES may require a tailored BP management distinct from strategies used for other stroke subtypes.

The optimal systolic BP for favorable outcomes was centered at approximately 122 mm Hg in our cohort, and the mean systolic BP was 134 mm Hg. Patients with BP ≥140 mm Hg had significantly worse outcomes, including a higher risk of END and lower odds of functional independence at 3 months.

Compared to prior studies, our analysis offers greater precision. We were able to capture detailed temporal fluctuations and better characterize both the mean BP and BPV. Additionally, our study included a large and well-defined CES cohort with robust statistical adjustments for baseline characteristics and treatment variables. The relatively low proportion of patients with extremely high BP in our histogram supports the hypothesis that lower BP thresholds may be tolerated and are potentially beneficial for CES. These data reinforce the importance of reevaluating uniform BP management strategies in stroke and pave the way for subtype-specific targets in future clinical guidelines.

This study had several limitations. This was a retrospective, single-center study, which limits its generalizability. Infarct size and location were not quantified because of the lack of imaging-based volumetric data; however, the National Institutes of Health Stroke Scale was used as a surrogate for stroke severity. The BP data lacked information on BP control, and short-term fluctuations may have been underestimated despite high-frequency sampling. Finally, mild cases that are not admitted to the monitored units may be underrepresented.

In conclusion, our findings suggest that in CES, mean BP during the early stroke period plays a more critical role in prognosis than BPV. Systolic BP ≥140 mm Hg was independently associated with an increased risk of END, poor functional recovery, and higher mortality. The optimal BP for favorable outcomes was closer to 122 mm Hg. These results highlight the need for stroke subtype-specific BP management strategies and support future prospective trials to define individualized targets for CES.