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Page 6 of 20 Akinci et al. Vessel Plus 2021;5:56 https://dx.doi.org/10.20517/2574-1209.2021.20

American Heart Association/American Stroke Association (AHA/ASA) made its last guidance update on
spontaneous ICH in 2015. There were concerns that acute BP lowering may worsen cerebral injury based on
the idea that ischaemic penumbra in the vicinity of hematoma may progress to permanent cerebral injury if
BP is lowered quickly and too much but studies indicated that BP reduction decreases hematoma expansion
without affecting perihematomal blood flow [51-54] . Also, although it was argued for heterogeneity of used
antihypertensive drugs, the INTERACT-2 showed that aggressive (target SBP < 140 mmHg within 1 h) BP
lowering is feasible and safe and, moreover, it can be effective for improving better functional outcome
[49]
compared with conservative BP lowering . Therefore, unlike previous guidelines that were hesitant and
cautious in aggressive BP lowering, the 2015 guidelines recommended acute lowering of SBP to 140 mmHg
for patients presenting with SBP between 150-220 mmHg and without contraindication to acute BP
treatment (class I; level of evidence A) and considering aggressive reduction of BP with a continuous IV
infusion and frequent BP monitoring for those presenting with SBP > 220 mmHg (class IIb; level of
evidence C). However, there were no specific recommendations regarding the treatment window and the
type of antihypertensive agent and route of administration .
[39]
According to European Stroke Initiative’s 2006 recommendations, the necessary BP target was different for
those with and without previous history of hypertension and suggestions were hesitant and cautious in
aggressive BP lowering as a hypertensive patient may not be able to maintain cerebral perfusion at a
significantly lower SBP. If the patient has a history of hypertension and SBP > 180 mmHg or DBP >
105 mmHg, it was recommended to reduce BP to < 170/100 mmHg or MAP to < 125 mmHg, avoiding
lowering pressure by more than 20% of MAP on admission (class IV; level C). For patients with unknown
history of hypertension, if SBP > 160 mmHg or DBP > 95 mmHg, it was recommended to reduce BP to <
150/90 mmHg or MAP to < 100 mmHg, avoiding lowering pressure by more than 20% of MAP on
admission (class IV; level C). It was also recommended to adapt thresholds to cerebral perfusion pressure >
[55]
70 mmHg (class IV; level C) and to use IV drugs for better control (good clinical practice) . These
recommendations were updated by European Stroke Organisation in 2014. Updated guidelines
recommended intensive BP reduction (target SBP < 140 mmHg in < 1 h) in ICH within 6 h of onset without
recommending a specific agent, noting that it is safe and may be superior to a SBP target of < 180 mmHg
(quality of evidence moderate, strength of recommendation weak). No recommendation has been made
[40]
regarding the lower limit of BP . At the time of writing this article, “Management of Hypertension in
Acute Ischemic Stroke and Intracerebral Hemorrhage” guideline was in development.

BLOOD PRESSURE REDUCTION IN ACUTE ICH IN RANDOMIZED TRIALS AND META-
ANALYSIS
The debate about whether to treat hypertension in acute stroke patients started 36 years ago . After 1997,
[56]
the relationship between acute hypertensive response and hematoma expansion, which was not
recommended to be treated due to perihematomal ischemia concerns, began to be elucidated, and moderate
lowering of BP was recommended based on the case series results . Since 2004, the effects of aggressive BP
[57]
lowering on hematoma expansion and patient outcomes have continued to be investigated. Although we
have some information about the safety of treatment of acute hypertensive response at the point we have
reached in 36 years, we can state that our knowledge about the benefits of treatment, timing of treatment,
medications that should be used, the treatment threshold and target BP is still insufficient. Randomized
clinical trials (see Table 1) with variable antihypertensive agents, different theoropathic windows and
thresholds, different sample sizes and different time frames to achieve target BP, and related subgroup
analyzes and meta-analyzes make it difficult to reach a definite conclusion.