Background: Early elevation of blood pressure after an acute intracerebral bleed is strongly associated with hematoma growth and worse outcomes. The pilot phase of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT) showed that early intensive blood pressure lowering reduced hematoma growth within six hours after onset of intracerebral hemorrhage.
Study design: Randomized controlled trial in which patients received an early intensive blood-pressure-lowering treatment (goal SBP<140 mmHg within one hour) or the AHA recommended best practice guidelines (goal SBP <180 mmHg), which were published in 1999.
Setting: Network of hospitals in China, South Korea, and Australia.
Synopsis: From 2005 to 2007, the study examined 404 patients with computed-tomography (CT) evidence of intracerebral hemorrhage, elevated SBP (150 mmHg-220 mmHg), and ability to commence BP lowering treatment within six hours of onset. Hematoma volumes were measured in the intensive treatment and guideline groups based on CT scans done at baseline and after 24 hours.
No significant association was found between the baseline SBP and the absolute or proportional growth of the hematoma. However, in the intensively treated patients who achieved target SBP within the first 24 hours, a significant association was found with the absolute and proportional hematoma growth.
Maximum reduction of hematoma growth occurred in the group with a median SBP of 135 mmHg.
This single-observational study did not include patients with severe intracranial bleeding who died or required surgical evacuation within the first 24 hours.
Hematoma size reduction did not improve survival or outcomes.
Bottom line: Intensive SBP lowering from 140 mmHg to 130 mmHg within one hour reduces hematoma growth after an intracranial hemorrhage.
Citation: Arima H, Anderson CS, Wang JG, et al. Lower treatment blood pressure is associated with the greatest reduction in hematoma growth after acute intracerebral hemorrhage. Hypertension. 2010;56(5):852-858.
Implantable Cardioverter-Defibrillator (ICD) Therapy for Primary Prevention of Sudden Cardiac Death Might Not Provide Survival Benefit to Elderly
Clinical question: Does ICD therapy for primary prevention of sudden cardiac death in individuals with severe left ventricular dysfunction improve survival in elderly patients?
Background: Several clinical trials of select individuals with severe left ventricular dysfunction (EF <40%) have demonstrated that ICD therapy is associated with a reduction in overall mortality. Given the costs and risks associated with ICD placement, it is important to assess how this therapy affects survival in younger versus older individuals.
Study design: Meta-analysis of five randomized controlled trials.
Setting: Five trials (MADIT-II, DEFINITE, DINAMIT, SCDHeFT, and IRIS).
Synopsis: All included studies compared ICD therapy to standard medical care in the primary prevention of sudden cardiac death in individuals with severe left ventricular dysfunction. Elderly patients comprised 44% of the 5,783 patients included in the study; elderly patients were defined as >65 in three studies, and >60 in two studies. Pooled analysis of the three trials examining ICD use for primary prevention found a nonsignificant reduction in all-cause mortality compared with medical therapy in elderly patients (HR 0.81 [95% CI 0.62 to 1.05], P=0.11). The two remaining studies involving post-MI patients showed no statistically significant reduction in mortality in elderly patients.
In contrast, pooled data from younger patients in the five trials showed that prophylactic ICD therapy reduced all-cause mortality.
None of the selected trials demonstrated evidence of selection, performance, detection, or attrition bias. Only a small number of studies were included, and four potentially relevant trials were not included because mortality data by age group were not available.
Trials including cardiac resynchronization therapy (CRT) were excluded from this meta-analysis, and elderly patients meeting criteria for CRT comprise an important group that must be considered separately.