Stable angina pectoris: the medical management of symptomatic myocardial ischemia

Association between stable angina pectoris and gastric cancer: two-sample bidirectional mendelian randomization study

To explore the possible causal link between stable angina pectoris (SAP) and gastric cancer (GC) through Mendelian randomization analysis. We used data from genome-wide association studies (GWAS) statistical datasets, with SAP and GC screened as relevant instrumental variables for exposure factors, respectively. To evaluate the causal link between SAP and GC, a two-sample bidirectional Mendelian randomization analysis was conducted, leveraging genetic variants as instrumental variables. In addition, effects of horizontal pleiotropy were evaluated using MR-PRESSO and MR-Egger intercept analysis. Sensitivity analysis was performed using Cochran Q test and "leave one out" method. The study showed a significant causal relationship between SAP and GC in the analysis with SAP as the exposure variable (odds ratio [OR] = 0.78, 95% confidence interval [CI] = 0.69-0.87, p = 0.000027 using inverse variance weighting [IVW]). Sensitivity analysis confirmed the robustness of Mendelian randomization results. In the analysis of GC as an exposure variable, gastric cancer and SAP also showed a significant causal association (OR = 0.87, 95%CI = 0.77-0.98, p = 0.024 using IVW), but sensitivity analysis suggested a significant pleiotropy between instrumental variables (p = 0.0093 using MR-Egger intercept analysis), which cast doubt on the reliability of the study and requires careful interpretation of the results. Existing studies suggest that individuals with SAP may have a lower risk of developing GC. However, the precise causal relationship, particularly regarding whether GC contributes to an increased risk of SAP, remains unclear and warrants further investigation. GC and ischemic heart disease which represented by SAP are both associated with oxidative stress in their pathogenesis. Local tissue-induced mitochondrial autophagy or cellular ferroptosis triggers a systemic response, potentially underlying the negative correlation between GC and SAP. Thus, therapeutic strategies that target the interplay between local tissue and systemic responses in oxidative stress may hold promise for the benefits to patients.

Updates on Pharmacologic Management of Microvascular Angina

Microvascular angina (MVA), historically called cardiac syndrome X, refers to angina with nonobstructive coronary artery disease. This female-predominant cardiovascular disorder adds considerable health-related costs due to repeated diagnostic angiography and frequent hospital admissions. Despite the high prevalence of this diagnosis in patients undergoing coronary angiography, it is still a therapeutic challenge for cardiologists. Unlike obstructive coronary artery disease, with multiple evidence-based therapies and management guidelines, little is known regarding the management of MVA. During the last decade, many therapeutic interventions have been suggested for the treatment of MVA. However, there is a lack of summarization tab and update of current knowledge about pharmacologic management of MVA, mostly due to unclear pathophysiology. In this article, we have reviewed the underlying mechanisms of MVA and the outcomes of various medications in patients with this disease. Contrary to vasospastic angina in which normal angiogram is observed as well, nitrates are not effective in the treatment of MVA. Beta-blockers and calcium channel blockers have the strongest evidence of improving the symptoms. Moreover, the use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, statins, estrogen, and novel antianginal drugs has had promising outcomes. Investigations are still ongoing for vitamin D, omega-3, incretins, and n-acetyl cysteine, which have resulted in beneficial initial outcomes. We believe that the employment of the available results and results of the future large-scale trials into cardiac care guidelines would help reduce the global cost of cardiac care tremendously.

Lipase-Catalyzed Kinetic Resolution of Alcohols as Intermediates for the Synthesis of Heart Rate Reducing Agent Ivabradine

Ivabradine (Corlanor®), is a chiral benzocycloalkane currently employed and commercialized for the treatment of chronic stable angina pectoris and for the reduction in sinus tachycardia. The eutomer (S)-ivabradine is usually produced via chiral resolution of intermediates, by employing enantiopure auxiliary molecules or through preparative chiral HPLC separations. Recently, more sustainable biocatalytic approaches have been reported in literature for the preparation of the chiral amine precursor. In this work, we report on a novel biocatalyzed pathway, via a resolution study of a key alcohol intermediate used as a precursor of the chiral amine. After screening several enzymatic reaction conditions, employing different lipases and esterases both for the esterification and hydrolysis reactions, the best result was achieved with Pseudomonas cepacia Lipase and the final product was obtained in up to 96:4 enantiomeric ratio (e.r.) of an ivabradine alcohol precursor. This enantiomer was then efficiently converted into the desired amine in a facile three step synthetic sequence.

Selection of essential medicines for the prevention and treatment of cardiovascular diseases in low and middle income countries

BACKGROUND

The incidence and mortality of cardiovascular diseases (CVDs) in low and middle income countries (LMICs) have been increasing, while access to CVDs medicines is suboptimal. We assessed selection of essential medicines for the prevention and treatment of CVDs on national essential medicines lists (NEMLs) of LMICs and potential determinants for selection.

METHODS

Only operational NEMLs were considered eligible for this study. A selection of medicines listed under "cardiovascular medicines" or "blood products and plasma substitutes" in the NEMLs were included if they were present on international guidelines for the prevention and treatment of CVDs (hyperlipidemia, hypertension, platelet inhibition, ischemic stroke, stable ischemic heart disease, acute coronary syndromes, heart failure, atrial fibrillation, peripheral arterial disease and acute limb ischemia). The number and diversity of essential medicines selected for CVDs were studied. Moreover, determinants of selection of essential medicines for CVDs at a national level were explored. Data analysis was done using univariate linear regression and non-parametric tests.

RESULTS

All medicine groups listed by the international guidelines were selected by the majority of the 34 countries studied with the exception of adenosine diphosphate receptor inhibitors which appeared on less than half of the NEMLs studied (41% of countries). The total number of essential medicines for the prevention and treatment of cardiovascular diseases (median 24 (range 16-50)) differed significantly across income levels (median range: 19.5-25, p = 0.014) and across regions (median range: 20-32, p = 0.049). When recommendations of the international guidelines were considered, over 75% of the NEMLs contained essential medicines for the majority of CVDs.

CONCLUSION

The main medicine classes for the management of CVDs were represented on NEMLs. Consequently, for the majority of CVDs, evidence-based guideline-recommended treatment is possible as far as selection of essential medicines is concerned. Selection will therefore not be the limiting step in access to medicines for cardiovascular diseases.

Cardiac Syndrome X: Update

Cardiac Syndrome X (CSX), characterized by angina-like chest discomfort, ST segment depression during exercise, and normal epicardial coronary arteries at angiography, is highly prevalent in women. CSX is not benign, and linked to adverse cardiovascular outcomes and a poor quality of life. Coronary microvascular and endothelial dysfunction and abnormal cardiac nociception have been implicated in the pathogenesis of CSX. Treatment includes life-style modification, anti-anginal, anti-atherosclerotic, and anti-ischemic medications. Non-pharmacological options include cognitive behavioral therapy, enhanced external counterpulsation, neurostimulation, and stellate ganglionectomy. Studies have shown the efficacy of individual treatments but guidelines outlining the best course of therapy are lacking.

Myocardial ischaemia and cardiac pain - a mysterious relationship

Pain related to cardiac disease has been recognised for centuries. However, the precise mechanisms of angina pectoris remain bafflingly obscure. Conventional cardiological angina management concentrates on methods to improve oxygen delivery to cardiac myocytes as our understanding of cardiac muscle cells' response to hypoxia increases. In common with other chronic visceral pain syndromes, little is understood about how pain signals are generated and propagated by visceral nerves. Improved imaging and other physiological assessments have demonstrated important central nervous system (CNS) responses to myocardial ischaemia, including activation of CNS areas known to be 'key players' in chronic pain syndromes. Patients with stable angina usually have an excellent prognosis, especially if left ventricular function is preserved. Educating patients about their condition, teaching simple techniques known to help chronic pain patients and introducing targeted pain treatments specific to angina can be extremely helpful adjuncts to conventional cardiological treatments and will often bring about significant improvements in quality of life.

Cardiac Syndrome X: update 2014

Cardiac Syndrome X (CSX), characterized by angina-like chest discomfort, ST segment depression during exercise, and normal epicardial coronary arteries at angiography, is highly prevalent in women. CSX is not benign, and linked to adverse cardiovascular outcomes and a poor quality of life. Coronary microvascular and endothelial dysfunction and abnormal cardiac nociception have been implicated in the pathogenesis of CSX. Treatment includes life-style modification, anti-anginal, anti-atherosclerotic, and anti-ischemic medications. Non-pharmacological options include cognitive behavioral therapy, enhanced external counterpulsation, neurostimulation, and stellate ganglionectomy. Studies have shown the efficacy of individual treatments but guidelines outlining the best course of therapy are lacking.

Impact of self-management interventions on stable angina symptoms and health-related quality of life: a meta-analysis

Background

Chronic stable angina (CSA) has a major negative impact on health-related quality of life (HRQL) including poor general health status, psychological distress, and inability to self-manage.

Methods

We used meta-analysis to assess the effectiveness of self-management interventions for improving stable angina symptoms, HRQL and psychological well-being. Nine trials, involving 1,282 participants in total, were included. We used standard inverse-variance random-effects meta-analysis to combine the trials. Heterogeneity between trials was evaluated using chi-square tests for the tau-squared statistic and quantified using the I² statistic.

Results

There was significant improvement in the frequency of angina symptoms (Seattle Angina Questionnaire [SAQ], symptom diary) across trials, standardized mean difference (SMD): 0.30 (95% Confidence interval [CI] 0.14, 0.47), as well as reduction in the use of sublingual (SL) nitrates, SMD: -0.49 (95% CI -0.77, -0.20). Significant improvements for physical limitation (SAQ), SMD: 0.38 (95% CI 0.20, 0.55) and depression scores (Hospital Anxiety and Depression Scale), SMD: -1.38 (95% CI -2.46, -0.30) were also found. The impact of SM on anxiety was uncertain due to statistical heterogeneity across trials for this outcome, I² = 98%. SM did not improve other HRQL dimensions including angina stability, disease perception, and treatment satisfaction.

Conclusions

SM interventions significantly improve angina frequency and physical limitation; they also decrease the use of SL nitrates and improve depression in some cases. Further work is needed to make definitive conclusions about the impact of SM on cardiac-specific anxiety.