Beta-Blocker and Calcium Channel Blocker Toxicity With BRASH Syndrome: A Case Report.

Atrioventricular (AV) nodal blockers have a wide variety of medical uses, including the management of hypertension and cardiac arrhythmias. Like any other drug, they can carry side effects and toxicity. We present a case of a patient with a constellation of findings consistent with bradycardia, renal failure, AV nodal blockade, shock, and hyperkalemia (BRASH) syndrome. A 75-year-old female with a history of paroxysmal atrial fibrillation and heart failure with preserved ejection fraction presented to the hospital with shortness of breath. She was discharged two weeks prior to the presentation from another hospital after being treated for atrial fibrillation with a rapid ventricular response. She was discharged on metoprolol and diltiazem. Upon presentation to the hospital, the patient was noted to be bradycardic and hypotensive with blood work notable for acute kidney injury and hyperkalemia, consistent with BRASH syndrome. She received a dose of intravenous (IV) glucagon followed by infusion and received epinephrine infusion. Once clinically stable, she was discharged with her home dose of metoprolol and a reduced dose of diltiazem with a close follow-up with cardiology. Early recognition of BRASH syndrome as a unique clinical entity rather than different pathologic conditions is important to improve morbidity and mortality in these patients.

Refractory Shock from Amlodipine Overdose Overcomed with Hyperinsulinemia.

Intoxication from calcium channel blockers exhibits almost 50% mortality rates. Amlodipine is a long-acting dihydropyridine and inappropriate dosage poses a great threat for profound vasodilation, hypotension, and refractory vasopressor-resistant shock. A 72-year-old woman with unremarkable medical history presented to the emergency department due to amlodipine overdose after a suicide attempt attributed to COVID-19 pandemic severe anxiety disorder. Vital signs at presentation: heart rate 82 beats/ min, arterial pressure 72/55 mmHg, and oxygen saturation 98%. Resuscitation was initiated with intravenous infusion of normal saline 0,9%, noradrenaline, and calcium chloride, while activated charcoal was orally administrated; however, blood pressure remained at 70/45 mmHg. Abruptly, she experienced acute pulmonary edema and was finally intubated. We commenced high-dose insulin infusion with Dextrose 10% infusion to maintain euglycemic hyperinsulinemia. Hemodynamic improvement occurred after 30 min, systolic blood pressure raised to 95 mmHg, and decongestion was achieved with intravenous furosemide. Insulin effect was dose-dependent and patient's hemodynamic status improved after insulin uptitration. Eight days later, the patient was weaned from the mechanical ventilation and she was successfully discharged after 14 days. High-dose intravenous infusion of insulin up to 10 units/kg per hour appears as an inotropic agent possibly through alterations in myocardial metabolism of fatty acids and augmentation of insulin secretion and uptake. This regimen possibly exhibits additional vasotropic properties. We conclude that euglycemic hyperinsulinemia is a potentially advantageous treatment in CCB toxicity.

FDA approved L-type channel blocker Nifedipine reduces cell death in hypoxic A549 cells through modulation of mitochondrial calcium and superoxide generation.

As hypoxia is a major driver for the pathophysiology of COVID-19, it is crucial to characterize the hypoxic response at the cellular and molecular levels. In order to augment drug repurposing with the identification of appropriate molecular targets, investigations on therapeutics preventing hypoxic cell damage is required. In this work, we propose a hypoxia model based on alveolar lung epithelial cells line using chemical inducer, CoCl2 that can be used for testing calcium channel blockers (CCBs). Since recent studies suggested that CCBs may reduce the infectivity of SARS-Cov-2, we specifically select FDA approved calcium channel blocker, nifedipine for the study. First, we examined hypoxia-induced cell morphology and found a significant increase in cytosolic calcium levels, mitochondrial calcium overload as well as ROS production in hypoxic A549 cells. Secondly, we demonstrate the protective behaviour of nifedipine for cells that are already subjected to hypoxia through measurement of cell viability as well as 4D imaging of cellular morphology and nuclear condensation. Thirdly, we show that the protective effect of nifedipine is achieved through the reduction of cytosolic calcium, mitochondrial calcium, and ROS generation. Overall, we outline a framework for quantitative analysis of mitochondrial calcium and ROS using 3D imaging in laser scanning confocal microscopy and the open-source image analysis platform ImageJ. The proposed pipeline was used to visualize mitochondrial calcium and ROS level in individual cells that provide an understanding of molecular targets. Our findings suggest that the therapeutic value of nifedipine may potentially be evaluated in the context of COVID-19 therapeutic trials.

Association of calcium channel blocker use with clinical outcome of COVID-19: A meta-analysis.

AIMS: This meta-analysis aims to analyze the association of calcium channel blocker (CCB) use with COVID-19 clinical outcomes. METHODS: PubMed, ProQuest, Science Direct, Scopus, and medRxiv databases were searched systematically in a limited period. The primary outcome was mortality. RESULTS: A total of 119,298 patients from 31 eligible studies were included. Pooled analysis of the random-effect model revealed CCB was not associated with reduced mortality (OR = 1.21 [95%CI: 0.98-1.49], p = 0.08). Interestingly, subgroup analysis in hypertensive patients revealed significantly reduced mortality (OR = 0.69 [95%CI: 0.52-0.91], p = 0.009). CONCLUSION: CCB usage was not associated with the outcome of COVID-19. However, CCB was associated with a decreased mortality rate in hypertensive COVID-19 patients.

Influence of Antihypertensive Treatment on RAAS Peptides in Newly Diagnosed Hypertensive Patients.

(1) Background: Recently, influences of antihypertensive treatment on the renin-angiotensin-aldosterone system (RAAS) has gained attention, regarding a possible influence on inflammatory and anti-inflammatory pathways. We aimed to study the effects of newly initiated antihypertensive drugs on angiotensin (Ang) II and Ang (1-7) as representers of two counter-regulatory axes. (2) Methods: In this randomized, open-label trial investigating RAAS peptides after the initiation of perindopril, olmesartan, amlodipine, or hydrochlorothiazide, Ang II and Ang (1-7) equilibrium concentrations were measured at 8 a.m. and 12 a.m. at baseline and after four weeks of treatment. Eighty patients were randomized (1:1:1:1 fashion). (3) Results: Between the four substances, we found significant differences regarding the concentrations of Ang II (p < 0.0005 for 8 a.m., 12 a.m.) and Ang (1-7) (p = 0.019 for 8 a.m., <0.0005 for 12 a.m.) four weeks after treatment start. Ang II was decreased by perindopril (p = 0.002), and increased by olmesartan (p < 0.0005), amlodipine (p = 0.012), and hydrochlorothiazide (p = 0.001). Ang (1-7) was increased by perindopril and olmesartan (p = 0.008/0.002), but not measurably altered by amlodipine and hydrochlorothiazide (p = 0.317/ 0.109). (4) Conclusion: The initiation of all first line antihypertensive treatments causes early and distinct alterations of equilibrium angiotensin levels. Given the additional AT1R blocking action of olmesartan, RAAS peptides shift upon initiation of perindopril and olmesartan appear to work in favor of the anti-inflammatory axis compared to amlodipine and hydrochlorothiazide.

Pharmacological hypothesis: TPC2 antagonist tetrandrine as a potential therapeutic agent for COVID-19.

More than ten million patients worldwide have been diagnosed with coronavirus disease 19 (COVID-19) to date (WHO situation report, 1st July 2020). There is no vaccine to prevent infection with the causative organism, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), nor a cure. In the struggle to devise potentially useful therapeutics in record time, the repurposing of existing compounds is a key route of action. In this hypothesis paper, we argue that the bisbenzylisoquinoline and calcium channel blocker tetrandrine, originally extracted from the plant Stephania tetrandra and utilized in traditional Chinese medicine, may have potential in the treatment of COVID-19 and should be further investigated. We collate and review evidence for tetrandrine's putative mechanism of action in viral infection, specifically its recently discovered antagonism of the two-pore channel 2 (TPC2). While tetrandrine's particular history of use provides a very limited pharmacological dataset, there is a suggestion from the available evidence that it could be effective at doses used in clinical practice. We suggest that further research to investigate this possibility should be conducted.