Updated treatment algorithm of pulmonary arterial hypertension

The demands on a pulmonary arterial hypertension (PAH) treatment algorithm are multiple and in some ways conflicting. The treatment algorithm usually includes different types of recommendations with varying degrees of scientific evidence. In addition, the algorithm is required to be comprehensive but not too complex, informative yet simple and straightforward. The type of information in the treatment algorithm are heterogeneous including clinical, hemodynamic, medical, interventional, pharmacological and regulatory recommendations. Stakeholders (or users) including physicians from various specialties and with variable expertise in PAH, nurses, patients and patients' associations, healthcare providers, regulatory agencies and industry are often interested in the PAH treatment algorithm for different reasons. These are the considerable challenges faced when proposing appropriate updates to the current evidence-based treatment algorithm.The current treatment algorithm may be divided into 3 main areas: 1) general measures, supportive therapy, referral strategy, acute vasoreactivity testing and chronic treatment with calcium channel blockers; 2) initial therapy with approved PAH drugs; and 3) clinical response to the initial therapy, combination therapy, balloon atrial septostomy, and lung transplantation. All three sections will be revisited highlighting information newly available in the past 5 years and proposing updates where appropriate. The European Society of Cardiology grades of recommendation and levels of evidence will be adopted to rank the proposed treatments.

Relative efficacy of catheter ablation vs antiarrhythmic drugs in treating premature ventricular contractions: a single-center retrospective study

BACKGROUND

It is unknown whether radiofrequency ablation (RFA) or antiarrhythmic therapy is superior when treating patients with symptomatic premature ventricular contractions (PVCs).

OBJECTIVE

To determine the relative efficacy of RFA and antiarrhythmic drugs (AADs) on PVC burden reduction and increasing left ventricular systolic function.

METHODS

Patients with frequent PVCs (>1000/24 h) were treated either by RFA or with AADs from January 2005 through December 2010. Data from 24-hour Holter monitoring and echocardiography before and 6-12 months after treatment were compared between the 2 groups.

RESULTS

Of 510 patients identified, 215 (40%) underwent RFA and 295 (60%) received AADs. The reduction in PVC frequency was greater by RFA than with AADs (-21,799/24 h vs -8,376/24 h; P < .001). The left ventricular ejection fraction (LVEF) was increased significantly after RFA (53%-56%; P < .001) but not after AAD (52%- 52%; P = .6) therapy. Of 121 (24%) patients with reduced LVEF, 39 (32%) had LVEF normalization to 50% or greater. LVEF was restored in 25 of 53 (47%) patients in the RFA group compared with 14 of 68 (21%) patients in the AAD group (P = .003). PVC coupling interval less than 450 ms, less impaired left ventricular function, and RFA were independent predictors of LVEF normalization performed by using multivariate analysis.

CONCLUSION

RFA appears to be more effective than AADs in PVC reduction and LVEF normalization.

Effect of American ginseng (Panax quinquefolius L.) on arterial stiffness in subjects with type-2 diabetes and concomitant hypertension

ETHNOPHARMACOLOGICAL RELEVANCE

Substantial pre-clinical and some clinical data are available showing that Asian ginseng (Panax ginseng C.A. Meyer) varieties or its particular ginsenosides exert a vasodilatating effect, thus may modulate vascular function. However, the clinical evidence for American ginseng (Panax quinquefolius L.) is scarce. Therefore, this study evaluates the effect of American ginseng (AG) on arterial stiffness, as measured by augmentation index (AI), and blood pressure (BP), in type 2 diabetes patients with concomitant hypertension.

MATERIALS AND METHODS

Using a double-blind, placebo-controlled, parallel design, each participant was randomized to either the selected AG extract or placebo at daily dose of 3g for 12 weeks as an adjunct to their usual antihypertensive and anti-diabetic therapy (diet and/or medications). AI and BP were measured by applanation tonometry at baseline and after 12 weeks of treatment.

RESULTS

A total of 64 individuals with well-controlled essential hypertension and type 2 diabetes (gender: 22 M:42 F, age:63 ± 9.3 years, BP: 145 ± 10.8/84 ± 8.0 mmHg, HbA1c: 7.0 ± 1.3%, fasting blood glucose (FBG): 8.1 ± 2.3 mmol/L) completed the study. Compared to placebo, 3g of AG significantly lowered radial AI by 5.3% (P=0.041) and systolic BP by 11.7% (P<0.001) at 12 weeks. No effect was observed with diastolic BP.

CONCLUSIONS

Addition of AG extract to conventional therapy in diabetes with concomitant hypertension improved arterial stiffness and attenuated systolic BP, thus warrants further investigation on long-term endothelial parameters before recommended as an adjunct treatment.

A meta-analysis of the effect of angiotensin receptor blockers and calcium channel blockers on blood pressure, glycemia and the HOMA-IR index in non-diabetic patients

OBJECTIVE

This study compared the efficacy of angiotensin receptor blockers (ARBs) and calcium channel blockers (CCBs) in the effect of insulin resistance (IR) as assessed using the homeostasis model assessment of insulin resistance (HOMA-IR) in non-diabetic patients.

METHODS

The MEDLINE, EMBASE, and Cochrane Library databases were searched to identify studies published before December 2012 that investigated the use of ARBs and CCBs to determine the effect on the HOMA-IR index in non-diabetics. Parameters on IR and blood pressure were collected. Review Manager 5.2 and Stata 12.0 were used to perform the meta-analysis. Fixed and random effects models were applied to various aspects of the meta-analysis, which assessed the therapeutic effects of the two types of drug using the HOMA-IR index in non-diabetic patients.

RESULTS

The meta-analysis included five clinical trials. Patient comparisons before and after treatment with ARBs and CCBs revealed that ARBs reduced the HOMA-IR index (weighted mean difference (WMD) -0.65, 95% confidence interval (CI) -0.93 to -0.38) and fasting plasma insulin (FPI) (WMD -2.01, 95% CI -3.27 to -0.74) significantly more than CCBs. No significant differences in the therapeutic effects of these two types of drug on blood pressure were observed.

CONCLUSION

Given that there are no significant differences in the therapeutic effects of ARBs and CCBs on blood pressure, as ARBs are superior to CCBs in their effect on the HOMA-IR index in non-diabetics, they might be a better choice in hypertension patients without diabetes.

Proteomic analysis for testis of mice exposed to carbon ion radiation

This paper investigates the mechanism of action of heavy ion radiation (HIR) on mouse testes. The testes of male mice subjected to whole body irradiation with carbon ion beam (0.5 and 4Gy) were analyzed at 7days after irradiation. A two-dimensional gel electrophoresis approach was employed to investigate the alteration of protein expression in the testes. Spot detection and matching were performed using the PDQuest 8.0 software. A difference of more than threefold in protein quantity (normalized spot volume) is the standard for detecting differentially expressed protein spots. A total of 11 differentially expressed proteins were found. Protein identification was performed using matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-TOF). Nine specific proteins were identified by searching the protein sequence database of the National Center for Biotechnology Information. These proteins were found involved in molecular chaperones, metabolic enzymes, oxidative stress, sperm function, and spermatogenic cell proliferation. HIR decreased glutathione activity and increased malondialdehyde content in the testes. Given that Pin1 is related to the cell cycle and that proliferation is affected by spermatogenesis, we analyzed testicular histological changes and Pin1 protein expression through immunoblotting and immunofluorescence. Alterations of multiple pathways may be associated with HIR toxicity to the testes. Our findings are essential for studies on the development, biology, and pathology of mouse testes after HIR in space or radiotherapy.

Renoprotective effects of stevia (Stevia rebaudiana Bertoni), amlodipine, valsartan, and losartan in gentamycin-induced nephrotoxicity in the rat model: Biochemical, hematological and histological approaches

The current study investigated the renoprotective effects of stevia, angiotensin-II type 1 receptor (AT1) blocker and calcium (Ca2+) channel blocker in gentamycin-induced nephrotoxicity in rat models. Six groups of male Sprague-Dawley rats of eight weeks old were taken for the experiment: sham control, nephrotoxicity, treatment with amlodipine (4 mg/kg/day); stevia (200 mg/kg/day); losartan (15 mg/kg/day) and valsartan (5 mg/kg/day), accordingly. The blood sample was taken for the assessment of renal and hepatic-functional variables like serum creatinine, blood urea, BUN and SGPT, SGOT, and total serum bilirubin. Hematological parameters were also examined. Histological examination has been done on kidneys and liver. Alterations of the body weight and the organ's weight were documented. Treatment with stevia and valsartan significantly decreased serum creatinine levels. A reduction of liver enzymes, and total serum bilirubin levels were observed in all the treatment groups. Treatment with valsartan and amlodipine, remarkably and stevia, mildly reduced the renal tissue damage, inflammation, and tubular necrosis. However, the present study demonstrated that losartan treatment aggravated kidney damage by increasing protein cast, calcification, tubular necrosis, and injury. This comparison indicated that both stevia and valsartan have beneficial renoprotective effect and valsartan offers a better treatment option in renal damage over losartan.

Repurposing calcium channel blockers as antiviral drugs

The current pandemic caused by the SARS-CoV-2 has claimed over a half a million lives within a very short span of time. A therapeutic drug which could prevent the entry and propagation of the virus is the need of the hour. Several lines of evidence collected from experimental studies older than three decades have pointed out the fact that inhibiting calcium entry into cells can affect vital steps in the lifecycle of viruses. Hence, calcium channel blockers may be considered as an effective measure in the containment of the viruses. This commentary throws light two scientific papers although with divergent facts converging at a point by suggesting a promising treatment option for CoVID-19 (Fang et al. Lancet Respir Med 8:e21, 2020; Straus et al. J Virol 94:e00426, 2020).

Differential effects of alloherpesvirus CyHV-3 and rhabdovirus SVCV on apoptosis in fish cells

Whilst Herpesviridae, which infect higher vertebrates, actively influence host immune responses to ensure viral replication, it is mostly unknown if Alloherpesviridae, which infect lower vertebrates, possess similar abilities. An important antiviral response is clearance of infected cells via apoptosis, which in mammals influences the outcome of infection. Here, we utilise common carp infected with CyHV-3 to determine the effect on the expression of genes encoding apoptosis-related proteins (p53, Caspase 9, Apaf-1, IAP, iNOS) in the pronephros, spleen and gills. The influence of CyHV-3 on CCB cells was also studied and compared to SVCV (a rhabdovirus) which induces apoptosis in carp cell lines. Although CyHV-3 induced iNOS expression in vivo, significant induction of the genetic apoptosis pathway was only seen in the pronephros. In vitro CyHV-3 did not induce apoptosis or apoptosis-related expression whilst SVCV did stimulate apoptosis. This suggests that CyHV-3 possesses mechanisms similar to herpesviruses of higher vertebrates to inhibit the antiviral apoptotic process.

Synthesis of novel calcium channel blockers with ACE2 inhibition and dual antihypertensive/anti-inflammatory effects: A possible therapeutic tool for COVID-19

Hypertension has been recognized as one of the most frequent comorbidities and risk factors for the seriousness and adverse consequences in COVID-19 patients. 3,4-dihydropyrimidin-2(1H) ones have attracted researchers to be synthesized via Beginilli reaction and evaluate their antihypertensive activities as bioisosteres of nifedipine a well-known calcium channel blocker. In this study, we report synthesis of some bioisosteres of pyrimidines as novel CCBs with potential ACE2 inhibitory effect as antihypertensive agents with protective effect against COVID-19 infection by suppression of ACE2 binding to SARS-CoV-2 Spike RBD. All compounds were evaluated for their antihypertensive and calcium channel blocking activities using nifedipine as a reference standard. Furthermore, they were screened for their ACE2 inhibition potential in addition to their anti‐inflammatory effects on LPS-stimulated THP‐1 cells. Most of the tested compounds exhibited significant antihypertensive activity, where compounds 7a, 8a and 9a exhibited the highest activity compared to nifedipine. Moreover, compounds 4a,b, 5a,b, 7a,b, 8a,c and 9a showed promising ACE2:SARS-CoV-2 Spike RBD inhibitory effect. Finally, compounds 5a, 7b and 9a exerted a promising anti-inflammatory effect by inhibition of CRP and IL-6 production. Ultimately, compound 9a may be a promising antihypertensive candidate with anti-inflammatory and potential efficacy against COVID-19 via ACE2 receptor inhibition.

Clinical outcomes of hypertensive patients with COVID-19 receiving calcium channel blockers: a systematic review and meta-analysis

We aimed to perform a systematic review and meta-analysis to determine the overall effect of the preadmission/prediagnosis use of calcium channel blockers (CCBs) on the clinical outcomes in hypertensive patients with COVID-19. A systematic literature search with no language restriction was conducted in electronic databases in July 2021 to identify eligible studies. A random-effects model was used to estimate the pooled summary measure for outcomes of interest with the preadmission/prediagnosis use of CCBs relative to the nonuse of CCBs at 95% confidence intervals (CIs). The meta-analysis revealed a significant reduction in the odds of all-cause mortality with the preadmission/prediagnosis use of CCBs relative to the nonuse of CCBs (pooled OR = 0.65; 95% CI 0.49-0.86) and a significant reduction in the odds of severe illness with preadmission/prediagnosis use of CCBs relative to the nonuse of CCBs (pooled OR = 0.61; 95% CI 0.44-0.84), and is associated with adequate evidence to reject the model hypothesis of 'no significant difference' at the current sample size. The potential protective effects offered by CCBs in hypertensive patients with COVID-19 merit large-scale prospective investigations.

Amlodipine (150 mg) Poisoning: A Case Study

BACKGROUND

Treatments of patients with amlodipine (a calcium channel blocker, CCB) overdose/poisoning remain challenging and death is certain if not intervened timely. Furthermore, for the society, the availability and common use of this drug can drive more vulnerable groups, especially children, towards an accidental/suicidal poisoning.

CASE REPORT

Herein, we describe the case of an 18 year-old-adolescent girl who took 150 mg of amlodipine with the suicidal intentions and was admitted in our hospital approximately 4-hours after the ingestion. She developed circulatory failure and tachypnea. Decontamination, calcium, glucagon, and dual vasopressors were started, however, persistent hypotension led to the initiation of hyperinsulinemiceuglycemia therapy. She recovered fully and discharged without any complications in few days. This case educates not only about the successful use of variant drugs in the management of CCB overdose/poisoning, but also calls for the attention of the society for a safe storage of often used drugs, especially away from the children/adolescents.

Cost-effectiveness of amlodipine compared with valsartan in preventing stroke and myocardial infarction among hypertensive patients in Taiwan

Hypertension is a major risk factor for strokes and myocardial infarction (MI). Given its effectiveness and safety profile, the calcium channel blocker amlodipine is among the most frequently prescribed antihypertensive drugs. This analysis was conducted to determine the costs and quality-adjusted life years (QALYs) associated with the use of amlodipine and valsartan, an angiotensin II receptor blocker, in preventing stroke and MI in Taiwanese hypertensive patients. A state transition (Markov) model was developed to compare the 5-year costs and QALYs for amlodipine and valsartan. Effectiveness data were based on the NAGOYA HEART Study, local studies, and a published meta-analysis. Utility data and costs of MI and stroke were retrieved from the published literature. Medical costs were based on the literature and inflated to 2011 prices; drug costs were based on National Health Insurance prices in 2014. A 3% discount rate was used for costs and QALYs and a third-party payer perspective adopted. One-way sensitivity and scenario analyses were conducted. Compared with valsartan, amlodipine was associated with cost savings of New Taiwan Dollars (NTD) 2,251 per patient per year: costs were NTD 4,296 and NTD 6,547 per patient per year for amlodipine and valsartan users, respectively. Fewer cardiovascular events were reported in patients receiving amlodipine versus valsartan (342 vs 413 per 10,000 patients over 5 years, respectively). Amlodipine had a net gain of 58 QALYs versus valsartan per 10,000 patients over 5 years. Sensitivity analyses showed that the discount rate and cohort age had a larger effect on total cost and cost difference than on QALYs. However, amlodipine results were more favorable than valsartan irrespective of discount rate or cohort age. When administered to Taiwanese patients for hypertension control, amlodipine was associated with lower cost and more QALYs compared with valsartan due to a lower risk of stroke and MI events.

Antihypertensive Therapy in Patients Receiving Maintenance Hemodialysis: A Narrative Review of the Available Clinical-Trial Evidence

BACKGROUND

Blood pressure (BP)-lowering with the use of antihypertensive drugs appears to protect the cardiovascular (CV) system in hemodialysis patients. However, the optimal treatment algorithm of hypertension remains elusive; extrapolation of clinical-trial evidence from the general population may not be optimal.

METHODS

For this narrative review, we searched the Medline/PubMed database (inception to August 01, 2019) to identify randomized clinical trials evaluating the efficacy of antihypertensive drugs on CV outcomes and mortality in patients on hemodialysis.

RESULTS

Randomized trials with angiotensin-converting-enzyme-inhibitors (ACEIs) or angiotensinreceptor- blockers (ARBs) failed to provide consistent cardioprotection. β-blockers may provide a more consistent CV benefit. Although some early clinical trials have shown that mineralocorticoid-receptorantagonists (MRAs) reduce CV mortality, the associated risk of hyperkalemia raises important safety concerns on the use of MRAs as add-on therapy.

CONCLUSION

Our first-line therapy of hypertension in hemodialysis is the assessment and management of dry-weight and optimization of dialysis prescription. Based on the available clinical-trial evidence, we prescribe atenolol 3 times/week after dialysis as the first-line pharmacological option of hypertension to our patients without specific indications for other agents. Long-acting dihydropyridines and ACEIs/ARBs are our second-line and third-line choices, respectively. We avoid using MRAs and await results from ongoing trials testing their safety and efficacy. In patients receiving maintenance hemodialysis, randomized trials are clearly warranted in order to define BP targets and the comparative effectiveness of different antihypertensive drugs.

Association of antihypertensive drugs with COVID-19 outcomes: a drug-target Mendelian randomization study

Background: Observational investigations have provided conflicting results regarding the effect of antihypertensive drugs on the risk of COVID-19 outcomes. We intended to assess the causal effect of antihypertensive drugs on COVID-19 outcomes using drug-target Mendelian randomization (MR), mainly including angiotensin-converting enzyme inhibitors (ACEIs), β-blockers (BBs) and calcium channel blockers (CCBs). Methods: We used the genetic variants (minor allele frequency >1%, r 2 < 0.30) located within 100 k bases of each drug target gene and associated with lower systolic blood pressure (p < 5 × 10-8) as genetic proxies for antihypertensive drugs. COVID-19 outcomes included COVID-19 susceptibility (122,616 cases and 2,475,240 controls), hospitalization (32,519 cases and 206,2805 controls), and severe illness (13,769 cases and 1,072,442 controls). All studies were conducted on populations of European ancestry. MR estimates were generated using an inverse variance weighted (IVW) model. Results: IVW-MR analysis observed a weak causality between CCBs and COVID-19 susceptibility (OR: 0.993, 95% CI: 0.988-0.999, p = 0.012). Sensitivity analysis suggested that this result was robust. No evidence was found for a link between other antihypertensive drugs and COVID-19 outcomes. Conclusion: The present study suggests that CCBs may reduce COVID-19 susceptibility in European populations.

Calcium channel blocker and risk of postoperation lymphatic-related complications among gynecologic malignances

Purpose

This study was performed to assess the association of calcium channel blockers (CCB) and other potential factors with postoperative lymphatic-related morbidity in patients with cervical cancer and endometrial carcinoma.

Methods

Patients diagnosed with cervical cancer or endometrial carcinoma with pelvic lymphadenectomy between January 2017 and January 2022 were enrolled. Postoperative lymphatic-related morbidity was evaluated by calculating the lymph cyst occurrence within 3 months after surgery and the duration of pelvic drainage. Univariate analyses evaluating the risk factors for lymphatic-related morbidity were performed.

Results

Of a total of 251 patients, 52 patients were diagnosed with lymphatic cysts by B-ultrasound or computed tomography, and the duration of drainage from 110 patients exceeded the average number of days. Univariable analysis revealed that hypertension, CCB, and lymph node metastasis were independent predictors of postoperative complications.

Conclusions

This study demonstrated that CCB may be a factor associated with the incidence of postoperation lymph cysts, and CCB usage prolongs the duration of pelvic drainage.