Treatment Resistant Hypertension

Effects of congeners of amphetamine on the human heart

Central stimulatory and hallucinogenic drugs of abuse like amphetamine and most congeners of amphetamine can have cardiac harmful effects. These cardiac side effects can lead to morbidities and death. In this paper, we review current knowledge on the direct and indirect effects of these amphetamine congeners on the mammalian heart-more specifically, the isolated human heart muscle preparation. In detail, we address the question of whether and how these drugs affect cardiac contractility and their mechanisms of action. Based on this information, further research areas are defined, and further research efforts are proposed.

Beyond Conventional Control: Insights Into Drug-Resistant Hypertension

It is believed that 9-18% of patients with hypertension have resistant hypertension, a serious medical disease. The increased cardiovascular risk associated with this illness demands appropriate diagnosis and treatment. It is necessary to conduct an in-depth investigation of the various etiologies, indicators of risk, and multiple disorders of resistant hypertension. This is crucial in order to establish the diagnosis and make the best decisions regarding therapy. Treatment should also take lifestyle changes into account in addition to medicinal and interventional therapy. When there is a suspicion of resistant hypertension, examining the medications used to treat the hypertensive patient after ruling out pseudo hypertension, improper blood pressure monitoring and control, and the white-coat effect are necessary. Resistant hypertension, according to a specific definition, is a condition that cannot be treated with more than two antihypertensive drugs, including a diuretic. An effective multidrug therapy for the treatment of resistant hypertension includes angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers, diuretics, long-acting calcium channel blockers, and mineralocorticoid receptor antagonists. However, alternative, cutting-edge treatments, such as renal denervation or baroreflex activation, could develop a brand-new avenue for decreasing blood pressure. These new surgical interventions might prove out to be of immense importance in coming times. Secondary causes of resistant hypertension, such as obstructive sleep apnea, coronary artery diseases, nephropathy, or endocrinal diseases, must be checked out in order to make an accurate diagnosis of this illness. This review article briefly summarizes the epidemiology, risk factors, causes, pathogenesis, diagnosis, and treatment approaches that may help with the long-term management of resistant hypertension.

Cardiac effects of ephedrine, norephedrine, mescaline, and 3,4-methylenedioxymethamphetamine (MDMA) in mouse and human atrial preparations

The use of recreational drugs like ephedrine, norephedrine, 3,4-methylenedioxymethamphetamine (MDMA), and mescaline can lead to intoxication and, at worst, to death. One reason for a fatal course of intoxication with these drugs might lie in cardiac arrhythmias. To the best of our knowledge, their inotropic effects have not yet been studied in isolated human cardiac preparations. Therefore, we measured inotropic effects of the hallucinogenic drugs ephedrine, norephedrine, mescaline, and MDMA in isolated mouse left atrial (mLA) and right atrial (mRA) preparations as well as in human right atrial (hRA) preparations obtained during cardiac surgery. Under these experimental conditions, ephedrine, norephedrine, and MDMA increased force of contraction (mLA, hRA) and beating rate (mRA) in a time- and concentration-dependent way, starting at 1-3 µM but these drugs were less effective than isoprenaline. Mescaline alone or in the presence of phosphodiesterase inhibitors did not increase force in mLA or hRA. The positive inotropic effects of ephedrine, norephedrine, or MDMA were accompanied by increases in the rate of tension and relaxation and by shortening of time of relaxation and, moreover, by an augmented phosphorylation state of the inhibitory subunit of troponin in hRA. All effects were greatly attenuated by cocaine (10 µM) or propranolol (10 µM) treatment. In summary, the hallucinogenic drugs ephedrine, norephedrine, and MDMA, but not mescaline, increased force of contraction and increased protein phosphorylation presumably, in part, by a release of noradrenaline in isolated human atrial preparations and thus can be regarded as indirect sympathomimetic drugs in the human atrium.

Hydralazine for essential hypertension

BACKGROUND

Hypertension is associated with an increased risk of stroke, myocardial infarction and congestive heart failure. Hydralazine is a direct-acting vasodilator which has been used for the treatment of hypertension since the 1950's. Although it has largely been replaced by newer antihypertensive drugs with more acceptable tolerability profiles, hydralazine is still widely used in developing countries due to its lower cost. A review of its relative effectiveness compared to placebo on surrogate and clinical outcomes is justified.

OBJECTIVES

To quantify the effect of hydralazine compared to placebo in randomized controlled trials (RCTs) on all cause mortality, cardiovascular mortality, serious adverse events, myocardial infarctions, strokes, withdrawals due to adverse effects and blood pressure in patients with primary hypertension.

SEARCH METHODS

We searched the following databases: Cochrane Central Register of Controlled Trials (2011, Issue 3), MEDLINE (1948-August 2011), International Pharmaceutical Abstracts (1970-June 2009) and EMBASE (1980-August 2011). Bibliographic citations from retrieved studies were also reviewed. No language restrictions were applied.

SELECTION CRITERIA

We selected RCTs studying the effect of oral hydralazine compared to oral placebo in patients with primary hypertension. We excluded studies of patients with secondary hypertension or gestational hypertension.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality using the risk of bias tool. Data synthesis and analysis was performed using RevMan 5.

MAIN RESULTS

The search strategy did not yield any randomized controlled trials comparing hydralazine to placebo for inclusion in this review. There is insufficient evidence to conclude on the effects of hydralazine versus placebo on mortality, morbidity, withdrawals due to adverse effects, serious adverse events, or systolic and diastolic blood pressure. Some of the adverse effects related to hydralazine that have been reported in the literature include reflex tachycardia, hemolytic anemia, vasculitis, glomerulonephritis, and a lupus-like syndrome.

AUTHORS' CONCLUSIONS

Hydralazine may reduce blood pressure when compared to placebo in patients with primary hypertension, however this data is based on before and after studies, not RCTs. Furthermore, its effect on clinical outcomes remains uncertain.

[Resistant hypertension despite nine different antihypertensive drugs?]

BACKGROUND

Treatment-resistant hypertension is a common problem in an outpatient setting and often results in hospital admission. Non-identified secondary hypertension, hypertensive nephrosclerosis and non-compliance are major reasons for treatment resistance.

CASE REPORT

A 75-year old woman was admitted to the emergency room because of a hypertensive crisis with alleged treatment-resistant hypertension and progressive headache. Two months ago, renal artery stenosis had been ruled out and a diagnosis of hypertensive cardiomyopathy was established. On admission, the patient had a blood pressure of 210/100 mmHg despite an antihypertensive treatment with nine different drugs. Further investigations ruled out secondary hypertension due to an endocrine cause but were consistent with hypertensive nephrosclerosis. With a supervised drug intake the blood pressure was rather normal to hypotensive, resulting in the need for significant reduction of the antihypertensive medication. The apparent discrepancies were discussed in detail with the patient who finally admitted a previous inconsistent intake of the antihypertensive drugs. Following thorough training and education on the purpose of continued antihypertensive therapy, the patient could be discharged with a normotensive blood pressure profile.

CONCLUSIONS

Therapy of treatment-resistant hypertension should always consider non-compliance and secondary hypertension as possible reason.

Hydralazine for essential hypertension

BACKGROUND

Hypertension is associated with an increased risk of stroke, myocardial infarction and congestive heart failure. Hydralazine is a direct-acting vasodilator which has been used for the treatment of hypertension since the 1950's. Although it has largely been replaced by newer antihypertensive drugs with more acceptable tolerability profiles, hydralazine is still widely used in developing countries due to its lower cost. A review of its relative effectiveness compared to placebo on surrogate and clinical outcomes is justified.

OBJECTIVES

To quantify the effect of hydralazine compared to placebo in randomized controlled trials (RCTs) on all cause mortality, cardiovascular mortality, serious adverse events, myocardial infarctions, strokes, withdrawals due to adverse effects and blood pressure in patients with primary hypertension.

SEARCH STRATEGY

We searched the following databases: Cochrane Central Register of Controlled Trials (to Second Quarter 2009), MEDLINE (2005-June 2009), International Pharmaceutical Abstracts (1970-June 2009) and EMBASE (2007-June 2009). Bibliographic citations from retrieved studies were also reviewed. No language restrictions were applied.

SELECTION CRITERIA

We selected RCTs studying the effect of oral hydralazine compared to oral placebo in patients with primary hypertension. We excluded studies of patients with secondary hypertension or gestational hypertension.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed trial quality using the risk of bias tool. Data synthesis and analysis was performed using RevMan 5.

MAIN RESULTS

The search strategy did not yield any randomized controlled trials comparing hydralazine to placebo for inclusion in this review. There is insufficient evidence to conclude on the effects of hydralazine versus placebo on mortality, morbidity, withdrawals due to adverse effects, serious adverse events, or systolic and diastolic blood pressure. Some of the adverse effects related to hydralazine that have been reported in the literature include reflex tachycardia, hemolytic anemia, vasculitis, glomerulonephritis, and a lupus-like syndrome.

AUTHORS' CONCLUSIONS

Hydralazine may reduce blood pressure when compared to placebo in patients with primary hypertension, however this data is based on before and after studies, not RCTs. Furthermore, its effect on clinical outcomes remains uncertain.