The protective action of amlodipine on cardiac negative inotropism caused by prolonged incubation in vitro

Rationale for the Inclusion of β-Blockers Among Major Antihypertensive Drugs in the 2023 European Society of Hypertension Guidelines

We address the reasons why, unlike other guidelines, in the 2023 guidelines of the European Society of Hypertension β-blockers (BBs) have been regarded as major drugs for the treatment of hypertension, at the same level as diuretics, calcium channel blockers, and blockers of the renin-angiotensin system. We argue that BBs, (1) reduce blood pressure (the main factor responsible for treatment-related protection) not less than other drugs, (2) reduce pooled cardiovascular outcomes and mortality in placebo-controlled trials, in which there has also been a sizeable reduction of all major cause-specific cardiovascular outcomes, (3) have been associated with a lower global cardiovascular protection in 2 but not in several other comparison trials, in which the protective effect of BBs versus the other major drugs has been similar or even greater, with a slightly smaller or no difference of global benefit in large trial meta-analyses and a similar protective effect when comparisons extend to BBs in combination versus other drug combinations. We mention the large number of cardiac and other comorbidities for which BBs are elective drugs, and we express criticism against the exclusion of BBs because of their lower protective effect against stroke in comparison trials, because, for still uncertain reasons, differences in protection against cause-specific events (stroke, heart failure, and coronary disease) have been reported for other major drugs. These partial data cannot replace global benefits as the main deciding factor for drug choice, also because in the general hypertensive population whether and which type of event might occur is unknown.

Intoxication with massive doses of amlodipine and candesartan requiring venoarterial extracorporeal membrane oxygenation

Background

Calcium channel blockers and angiotensin II receptor blockers are commonly prescribed to treat hypertension. Massive overdoses can cause both distributive and cardiogenic shock because of their effects on vascular smooth muscles and severe myocardial depression.

Case Presentation

We present the case of a 46-year-old man who was brought to our emergency department after ingesting 1210 mg amlodipine and 936 mg candesartan. The patient's hemodynamic status deteriorated despite treatment with vasopressors, calcium gluconate, and hyperinsulinemia-euglycemia therapy with mechanical ventilation. Venoarterial extracorporeal membrane oxygenation was initiated for refractory shock. The patient was weaned off extracorporeal membrane oxygenation on day 5 and discharged on day 18 of hospitalization.

Conclusion

When medical therapies are ineffective, aggressive venoarterial extracorporeal membrane oxygenation should be considered for the management of refractory shock in the setting of calcium channel blocker with angiotensin II receptor blocker overdose.

Protective Action of Amlodipine on Cardiac Negative Inotropism Induced by Lipopolysaccharide in Rats

Amlodipine has been shown to prevent decrease in vascular responsiveness induced by injection of Salmonella typhosa lipopolysaccharide (LPS); however, there is no study reporting if this protection by amlodipine extends to ventricular contractility. Therefore, we have investigated in rat isolated right ventricle strips contracted by electrical stimulation (1 and 3 Hz and subsequently 1 Hz) whether pre-treatment with amlodipine (15 mg/kg orally for 1 week) precludes the decrease in ventricular contractility related to the induction of nitric oxide synthase stimulated by LPS injection (4 mg/kg intraperitoneally). The induction of septic shock was confirmed in isolated aortic rings from LPS-injected rats by verifying that the contractile response to 1 microM noradrenaline had been (i) decreased after LPS injection and (ii) markedly potentiated by the addition of 10 microM l-arginine. The injection of saline to untreated and amlodipine-treated rats produced a non-significant effect on right ventricular contractility during 180 min. at 3 Hz; the recovery of the contractile response was improved when the stimulation frequency was subsequently returned to 1 Hz after 30 min. In contrast, injection of LPS to untreated and amlodipine-treated rats (amlodipine + LPS) produced a decrease in right ventricular contractility during 180 min. at 3 Hz, an effect that was more pronounced in LPS than in amlodipine-treated rats. These ex vivo results obtained after LPS injection suggest that amlodipine may have inhibited, at least in part, the induction of nitric oxide synthase with a resulting preclusion of the cardiovascular failure produced by septic shock.