Aggressive blood pressure control and stroke prevention: role of calcium channel blockers

Effects of calcium channel blockers on perioperative ischemic events in hypertensive patients with intracranial aneurysms undergoing neurointervention

BACKGROUND

Although calcium channel blockers (CCBs) are useful in stroke prevention, their specific role in preventing stroke in hypertensive patients with intracranial aneurysms undergoing endovascular stent placement remains unclear.

METHODS

We retrospectively examined 458 hypertensive patients with intracranial aneurysms who underwent stent treatment, drawn from a larger multicenter cohort comprising 1326 patients across eight centers. Patients were dichotomized into two groups according to use of a CCB. Propensity score matching (PSM) was performed to balance group differences in patient and aneurysm characteristics. We conducted a comparison of patient and aneurysm characteristics, ischemic complications, and clinical outcomes between the two groups.

RESULTS

The CCB and non-CCB groups comprised 279 and 179 patients, respectively. PSM resulted in 165 matched pairs. After PSM, the incidence of ischemic events within 1 month of the procedure (4.2% vs 10.9%; P=0.022) and proportion of patients with modified Rankin Scale score >2 at last follow-up (1.5% vs 7.8%; P=0.013) were significantly lower in the CCB group. Among patients treated with combination therapy, inclusion of a CCB was associated with a lower incidence of ischemic events (1.5% vs 13.3%; P=0.345), but the difference was not statistically significant after correction.

CONCLUSIONS

CCB use in hypertensive patients undergoing endovascular stenting for treatment of intracranial aneurysms is associated with a lower incidence of ischemic events and a lower incidence of unfavorable neurological outcomes, especially when used in combination therapy.

Association between dihydropyridine calcium channel blockers and ischemic strokes in patients with nonvalvular atrial fibrillation

Outside of clinical trials, the prophylactic effect of dihydropyridine calcium channel blockers (CCBs) on ischemic events in patients with nonvalvular atrial fibrillation (NVAF) has not been confirmed. We compared the effect of dihydropyridine CCBs on ischemic events in anticoagulated NVAF patients. We conducted a multicenter historical cohort study at 71 centers in Japan. The inclusion criterion was taking vitamin K antagonists for NVAF. The exclusion criteria were mechanical heart valves and a history of pulmonary thrombosis or deep vein thrombosis. Consecutive patients (N = 7826) were registered in February 2013 and were followed until February 2017. The primary outcomes were ischemic events and ischemic strokes; the secondary outcomes were all-cause mortality, major bleeding, and hemorrhagic strokes. The mean patient age was 73 years old, and 67% of the patients were male. Seventy-eight percent of the patients had hypertension, and dihydropyridine CCBs were used by 2693 (34%) patients (CCB group). The cumulative incidences of ischemic events and ischemic strokes at 4 years in the CCB and No-CCB groups were 5.9% vs. 5.2% and 5.6% vs. 4.8%, respectively. The adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) of the CCB group for ischemic events and ischemic strokes were 1.22 (0.95-1.57) and 1.32 (1.02-1.71), respectively; the adjusted HRs (95% CIs) of the CCB group for all-cause mortality, major bleeding, and hemorrhagic strokes were 0.85 (0.69-1.04), 1.12 (0.92-1.35), and 1.08 (0.62-1.88), respectively. Dihydropyridine CCB use by anticoagulated NVAF patients significantly increased ischemic strokes in a real-world setting.

Identification and Management of Ischemic Stroke in the Postanesthesia Care Unit

A thromboembolic stroke is a debilitating event that can occur with little or no warning. This report details the case of a 63-year-old male experiencing a stroke in the immediate postoperative period after total knee arthroplasty. Risk for perioperative stroke is influenced by age, sex, ethnicity, comorbidities, and some medications. The depressed neurocognitive state of patients recovering from anesthesia warrants special consideration for the identification and management of perioperative stroke.

Synergic effects of levamlodipine and bisoprolol on blood pressure reduction and organ protection in spontaneously hypertensive rats

AIMS

Stroke is a major cause of disability and death worldwide. Hypertension is one of the most important risk factors for stroke. The objective of this work was to study the synergic effects of levamlodipine and bisoprolol on blood pressure reduction and organ protection in spontaneously hypertensive rats (SHR).

METHODS

Blood pressure was continuously monitored in conscious SHR. For acute study, a single dose of drugs was administrated via an intragastric catheter. For chronic study (4 months), drugs were delivered via rat chow.

RESULTS

A single dose of levamlodipine (from 1 mg/kg), bisoprolol (from 0.125 mg/kg), and their combinations significantly decreased blood pressure. The levamlodipine-induced tachycardia and the bisoprolol-induced bradycardia were temporized by the combination of these two drugs. Upon chronic treatment, this combination also decreased blood pressure variability and reduced organ damage.

CONCLUSION

Levamlodipine and bisoprolol produce synergic effects on blood pressure reduction and organ protection in SHR.

From hypertension to stroke: mechanisms and potential prevention strategies

Stroke is a major cause of disability and death worldwide. Prevention aimed at risk factors of stroke is the most effective strategy to curb the stroke pandemic. Hypertension is one of the most important risk factors for stroke. Despite the substantial evidence of the benefits of lowering blood pressure, conventional treatment does not normalize the burden of major cardiovascular events in patients with hypertension. Fully understanding the factors involved in the hypertension-induced stroke helps to develop new strategies for stroke prevention. Antihypertensive therapies selected should have positive blood pressure-independent effects on stroke risk. This review summarizes the factors involved in the hypertension-induced stroke, such as oxidative stress, inflammation, and arterial baroreflex dysfunction, and potential strategies for its prevention, therefore, provides clues for clinicians.

Blood pressure reduction combining baroreflex restoration for stroke prevention in hypertension in rats

Blood pressure reduction is an important and effective strategy in stroke prevention in hypertensives. Recently, we found that baroreflex restoration was also crucial in stroke prevention. The present work was designed to test the hypothesis that a combination of blood pressure reduction and baroreflex restoration may be a new strategy for stroke prevention. In Experiment 1, the effects of ketanserin (0.3, 1, 3, 10 mg/kg), amlodipine (0.3, 1, 2, 3 mg/kg) and their combination (1 + 0.3, 1 + 1, 1 + 2, 1 + 3 mg/kg) on blood pressure and baroreflex sensitivity (BRS) of stroke-prone spontaneously hypertensive rats (SHR-SP) were determined under conscious state. It was found that both amlodipine and ketanserin decreased blood pressure dose-dependently. Ketanserin enfanced BRS from a very small dose but amlodipine enfanced BRS only at largest dose used. At the dose of 1 + 2 mg/kg (ketanserin + amlodipine), the combination possessed the largest synergism on blood pressure reduction. In Experiments 2 and 3, SHR-SP and two-kidney, two-clip (2K2C) renovascular hypertensive rats received life-long treatments with ketanserin (1 mg/kg) and amlodipine (2 mg/kg) or their combination (0.5 + 1, 1 + 2, 2 + 4 mg/kg). The survival time was recorded and the brain lesion was examined. It was found that all kinds of treatments prolonged the survival time of SHR-SP and 2K2C rats. The combination possessed a significantly better effect on stroke prevention than mono-therapies. In conclusion, combination of blood pressure reduction and baroreflex restoration may be a new strategy for the prevention of stroke in hypertension.

The Effects of gamma-Aminobutyric Acid, Vinegar, and Dried Bonito on Blood Pressure in Normotensive and Mildly or Moderately Hypertensive Volunteers

The purpose of this study was to examine the effects of γ-aminobutyric acid (GABA) in fermented drinking water prepared from sodium glutamate, vinegar, and dried bonito (FDWG) compared with placebo [vinegar and dried bonito without GABA (FDW)] and its safety in normotensive and mildly or moderately hypertensive volunteers. A double-blind, placebo-controlled, randomized study was conducted involving volunteers with normal (group-N) and mildly or moderately high (group-H) blood pressure (BP). After a pretreatment period of 2 weeks (weeks –2), the subjects received FDWG or FDW for 12 weeks followed by 4 weeks of no intake (weeks 16). In group-H, both FDWG and FDW significantly decreased systolic (SBP, −7.6 ± 4.0 and −5.5 ± 1.5 mmHg, p<0.05, respectively) and diastolic (DBP, −10.6 ± 4.0 and −7.6 ± 1.7 mmHg, p<0.01, respectively) BP compared to the baseline (0-week) value at 12 weeks, respectively. There were no abnormal changes in hematological or blood chemistry variables, urinalysis, heart rate, or body weight in the study groups. These findings indicated that vinegar and dried bonito with or without GABA might have an effect on BP in mildly or moderately hypertensive patients.

Inhibitory effect of antihypertensive drugs on calcineurin in cardiomyocytes

In recent years, a handful of research investigations have shown that some antihypertensive drugs, i.e., angiotensin-converting enzyme inhibitor (ACEI), angiotensin receptor blocker (ARB), and calcium channel blocker (CCB), can inhibit myocardial expression and/or activity of calcineurin. Calcineurin is a Ca(2+)-calmodulin-dependent serine/threonine phosphatase and is a target for some immunosuppressive drugs. It is well known that traditional immunosuppressants, such as cyclosporine A (CsA) and tacrolimus (FK506), are anticalcineurin, and their prohypertensive effects are such that antihypertensive therapy is often required in organ transplant recipients who receive these drugs. Therefore, the idea that ACEI, ARB, and CCBs are both antihypertensive and anticalcineurin seems paradoxical. This invited review tries to summarize these new findings and analyze the scientific and clinical significance of these claims. The review also emphasizes some of the shortcomings in these studies and some questions that need to be addressed in future investigations.

Heart rate, lifespan, and mortality risk

An increasing body of scientific research and observational evidence indicates that resting heart rate (HR) is inversely related to the lifespan among homeothermic mammals and within individual species. In numerous human studies with patients stratified by resting HR, increased HR is universally associated with greater risk of death. The correlation between HR and maximum lifespan seems to be due to both basal metabolic rate and cardiovascular-related mortality risk. Both intrinsic and extrinsic factors are already postulated to determine how the biological clock works, through regulating and modulating the processes such as protein oxidation, free radical production, inflammation and telomere shortening. Given the remarkable correlation between HR and lifespan, resting HR should be seriously considered as another possible cap on maximum lifespan. Future research is needed to determine whether deliberate cardiac slowing, through methods like lifestyle modification, pharmacological intervention, or medical devices, can decelerate biological clock of aging, reduce cardiovascular mortality and increase maximum lifespan in humans in general.