Current Cardiology Reports

Mặc dù có một khối lượng lớn nghiên cứu về liệu pháp chống đông cho bệnh nhân mắc bệnh tim, nhưng có rất ít tình huống lâm sàng mà bằng chứng cho lợi ích của chúng là mạnh mẽ. Bệnh nhân suy tim thường mắc các bệnh mạch máu và rung nhĩ, điều này góp phần vào tiên lượng kém. Đối với bệnh nhân suy tim và rung nhĩ, việc sử dụng thuốc chống đông là hợp lý. Đối với bệnh nhân suy tim có nhịp xoang, trọng lượng bằng chứng cho thấy các bác sĩ nên tránh sử dụng bất kỳ tác nhân chống đông nào, ngay cả khi bệnh nhân có bệnh lý động mạch vành. Nếu có nhu cầu điều trị, thì có ít bằng chứng về tác hại khi sử dụng clopidogrel hoặc warfarin hơn là với aspirin, mặc dù hầu hết bệnh nhân đều nhận aspirin. Cần có thêm nghiên cứu để giải quyết vấn đề "bằng chứng nhẹ" này. Đối với những người có cơ hội, việc tham gia vào một thử nghiệm ngẫu nhiên là hợp lý từ cả hai góc độ lâm sàng và khoa học. Dilemma đối với các nghiên cứu như vậy là so sánh. Nên so sánh với “tiêu chuẩn chăm sóc” hay thêm vào nó, hoặc cả hai?

As the rates of obesity and diabetes continue to rise sharply in the United States, there is a secondary epidemic of diabetic nephropathy, chronic kidney disease, and end-stage renal disease requiring renal replacement therapy. Cardiovascular disease is the leading cause of death in patients with renal disease. Many sources of information support the concept that the metabolic condition caused by renal failure is an independent cardiac risk factor with a direct relationship to the pathogenesis of atherosclerosis, acute coronary syndromes (ACS), heart failure, and arrhythmias. An estimated glomerular filtration rate less than 60 mL/min/1.73 m2 has consistently been shown to be the most powerful predictor of adverse outcomes in ACS. This paper focuses on ACS and highlights the major issues with respect to diagnosis and treatment in patients with underlying renal failure. Because patients with renal disease are routinely excluded from clinical trials of ACS, we draw upon a variety of clinical data sets to gather an evidenced-based approach to this important and growing population of patients.

Congestive heart failure is a pathologic condition characterized by progressive decrease in left ventricular contractility and consequent decline of cardiac output. There is convincing clinical and experimental evidence that the renin-angiotensin system (RAS) and its primary effector peptide, angiotensin II, are linked to the pathophysiology of interstitial fibrosis, cardiac remodeling, and heart failure. In addition to the traditional endocrine or circulating RAS, an active tissue RAS has been characterized. Tissue angiotensin-converting enzyme and locally synthesized angiotensin II, for example, by chymase, exert local trophic effects that modulate gene expression, which regulates growth and proliferation in both myocytes and nonmyocytes. The existence of the tissue RAS offers an opportunity for targeted imaging, which may be of considerable value for guiding medical therapy.

Recent studies have highlighted the critical importance of bleeding complications on prognosis in patients with acute coronary syndromes (ACS). In fact, the hazard for an adverse cardiovascular event associated with bleeding is similar to that of a myocardial infarction. Several bleeding risk scores are now available that reliably quantify the probability of an ACS patient experiencing a bleeding complication. Consistent and strong correlates of bleeding include older age, female sex, renal impairment, and an invasive management approach. Although patients who tend to bleed are usually more morbid compared with their non-bleeding counterparts, several lines of experimental and clinical evidence suggest an independent and causal pathway for bleeding-associated cardiovascular risk. Given the frequency and adverse prognosis associated with bleeding, interventions that might reduce such complications are now a major emphasis in the current era of ACS treatment. Recent trials have shown that several novel antithrombotics, bivalirudin and fondaparinux, reduce bleeding risk while maintaining efficacy in reducing ischemic events during ACS. Other promising strategies that continue to be tested include the use of vascular closure devices and transradial arterial access during percutaneous coronary intervention.

Evolution of the role of cardiac markers has ranged from the diagnosis of acute myocardial infarction in patients with nondiagnostic electrocardiograms to prognostic risk stratification and to guide therapy. The technology to provide rapid, real time measurements by immunoassay has provided the laboratory and clinician with a range of test options. The principal changes have been the use of rapid serial marker measurements of well-recognized cardiac markers, and the development of immunoassays for the cardiac structural proteins. Measurement of cardiac troponins has generated a new diagnostic paradigm in patients with suspected acute coronary syndromes. There is now a new gold standard biochemical test for myocardial infarction. A range of interventions can be guided by troponin measurement. The use of troponin measurements is central to management of patients with suspected acute coronary syndromes. Future developments in this field will focus on the role of existing and novel markers of inflammation and ischemia.

Aortic stenosis affects many people worldwide with a significant impact on morbidity and mortality with uncorrected, symptomatic aortic valve stenosis carrying mortality of 50 % at one year. Degenerative calcific pathology, the most common cause of aortic stenosis, increases in prevalence with age; estimated prevalence of 5 % in individuals over 75 years of age. Despite the malignant prognosis without valve replacement, many patients are not offered surgery due to advanced age and co-existing medical conditions; reported to be a third of symptomatic patients. In the last several years, transcatheter aortic valve replacement has emerged as an alternative treatment in patients with high or prohibitive open surgical risk. The PARTNER cohort B data, employing the Sapien valve, demonstrated a 20 % absolute mortality benefit at one year compared with medical therapy. In this review, we provide an update of this technology and discuss patient selection, procedural planning, complications, and look toward the future of transcatheter heart valves in the treatment of aortic stenosis.

Current hypertension guidelines do not provide recommendation on when-to-treat. Herein, we review the current evidence on ingestion-time differences of hypertension medications in blood pressure (BP)–lowering effects and prevention of cardiovascular disease (CVD) events. The vast (81.6%) majority of the 136 published short-term treatment-time trials document benefits, including enhanced reduction of asleep BP and increased sleep-time relative BP decline (dipping), when hypertension medications and their combinations are ingested before sleep rather than upon waking. Long-term outcome trials further document bedtime hypertension therapy markedly reduces risk of major CVD events. The inability of the very small 18.4% of the published trials to substantiate treatment-time difference in effects is mostly explained by deficiencies of study design and conduct. Our comprehensive review of the published literature reveals no single study has reported better benefits of the still conventional, yet scientifically unjustified, morning than bedtime hypertension treatment scheme.

Stable ischemic heart disease (SIHD) is a highly prevalent condition associated with increased costs, morbidity, and mortality. Management goals of SIHD can broadly be thought of in terms of improving prognosis and/or improving symptoms. Treatment options include medical therapy as well as revascularization, either with percutaneous coronary intervention or coronary artery bypass grafting. Herein, we will review the current evidence base for treatment of SIHD as well as its challenges and discuss ongoing studies to help address some of these knowledge gaps. There has been no consistent reduction in death or myocardial infarction (MI) with revascularization vs. medical therapy in patients with SIHD in contemporary trials. Angina and quality of life have been shown to be relieved more rapidly with revascularization vs. optimal medical therapy; however, the durability of these results is uncertain. There have been challenges and limitations in several of the trials addressing the optimal treatment strategy for SIHD due to potential selection bias (due to knowledge of coronary anatomy prior to randomization), patient crossover, and advances in medical therapy and revascularization strategies since trial completion. The challenges inherent to prior trials addressing the optimal management strategy for SIHD have impacted the generalizability of results to real-world cohorts. Until the results of additional ongoing trials are available, the decision for revascularization or medical therapy should be based on patients’ symptoms, weighing the risks and benefits of each approach, and patient preference.