Faculty Bibliography

OPINION STATEMENT: The pathogenesis of cardiovascular disease is a complex and dynamic process. The renin-angiotensin-aldosterone system (RAAS) is a potent and powerful mediator in the homeostasis of the cardiovascular and renal systems. RAAS blockade via angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) has been consistently proven to be an effective and safe strategy for the primary and secondary prevention of cardiovascular disease in patients across a wide spectrum of risk. Although the beneficial effects of RAAS blockade may be due to its effects on central and peripheral blood pressure, there are many additional mechanisms to consider that may contribute additional protection. While a combination of ACE inhibitors and ARBs has not yielded significantly positive results, the newer class of direct renin inhibitors (DRIs) may offer a novel and effective strategy for monotherapy as well as in combination

BACKGROUND: Stage 2 hypertension often requires combination antihypertensive therapy. Ambulatory blood pressure monitoring (ABPM) is a useful tool for studying antihypertensive drugs and their combinations. OBJECTIVE: This multicenter, double-blind, parallel-group, prompted-titration study of patients of at least 70 years of age with systolic hypertension compared the efficacy of valsartan, hydrochlorothiazide, and their combination on ambulatory blood pressure (ABP) reduction. METHODS: After a 3-14-day washout, patients with systolic blood pressure of 150-200 mmHg were randomized (1 : 1 : 1) to initially receive once-daily valsartan/hydrochlorothiazide 160/12.5 mg combination therapy, hydrochlorothiazide 12.5 mg monotherapy, or valsartan 160 mg monotherapy. Prompted uptitration of patients in whom BP was more than or equal to 140/90 mmHg was performed after 4, 8, and 12 weeks of treatment. ABPM was performed at baseline and weeks 4 and 16 (study end). RESULTS: In this ABPM substudy (n=108), initiation of treatment with valsartan/hydrochlorothiazide lowered ABP more effectively than either monotherapy throughout the daytime, night-time, and 24-h monitoring periods, as well as during the last 4 and 6-h dosing periods. Twenty-four-hour ABP was reduced from 141.1/76.5 mmHg at baseline to 125.8/69.2 mmHg at week 4 (primary time point) with valsartan/hydrochlorothiazide compared with reductions from 142.2/78.7 to 139.1/77.5 mmHg with hydrochlorothiazide and 142.2/78.3 to 136.4/75.1 mmHg with valsartan (all P<0.01 in favor of combination therapy). In the overall study, tolerability was similar among the three treatment groups. CONCLUSION: In elderly hypertensives, starting combination therapy with valsartan/hydrochlorothiazide provides more effective 24-h blood pressure control than the monotherapy components, with few therapy-related side-effects

There is now clear evidence that reducing blood pressure (BP) with a broad range of agents, including angiotensin converting enzyme inhibitors and angiotensin receptor blockers, improves cardiovascular and renal outcomes. There is also evidence suggesting that these drugs have beneficial effects that are independent of BP lowering. Aliskiren is a direct renin inhibitor that interrupts the renin-angiotensin-aldosterone system (RAAS) at its rate-limiting step. Unlike angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, aliskiren produces a sustained reduction in plasma renin activity and reduces plasma levels of angiotensin II and aldosterone. Preclinical data and clinical trials in high-risk patients using surrogate markers increasingly suggest that aliskiren can reduce the progression of end-organ damage beyond that afforded by BP control. With its unique mechanism of action, combining aliskiren with another RAAS-blocking agent that has a different mechanism of action may provide more comprehensive blockade of the RAAS, potentially conferring additional clinical benefits. Evaluation of these end-organ effects in humans is underway in clinical trials designed to assess the effects of aliskiren alone and in combination with other antihypertensive agents on cardiovascular and renal outcomes

Omega-3 fatty acids, which are found abundantly in fish oil, are increasingly being used in the management of cardiovascular disease. It is clear that fish oil, in clinically used doses (typically 4 g/d of eicosapentaenoic acid and docosahexaenoic acid) reduce high triglycerides. However, the role of omega-3 fatty acids in reducing mortality, sudden death, arrhythmias, myocardial infarction, and heart failure has not yet been established. This review will focus on the current clinical uses of fish oil and provide an update on their effects on triglycerides, coronary artery disease, heart failure, and arrhythmia. We will explore the dietary sources of fish oil as compared with drug therapy, and discuss the use of fish oil products in combination with other commonly used lipid-lowering agents. We will examine the underlying mechanism of fish oil's action on triglyceride reduction, plaque stability, and effect in diabetes, and review the newly discovered anti-inflammatory effects of fish oil. Finally, we will examine the limitations of current data and suggest recommendations for fish oil use

Chronic angina pectoris affects millions of patients every year. During the past 2 decades, advances in medical therapy have led to substantial reductions in the symptoms of angina. Nonetheless, many patients continue to experience persistent angina that causes debilitating symptoms and lifestyle changes. Moreover, many current therapeutic agents cause side effects that can induce substantial morbidity on their own. In major clinical trials, the drug ranolazine has been shown to bring symptomatic relief to large numbers of patients who have chronic angina. Herein, we review the physiology of the sodium channel; the pharmacology of ranolazine; clinical trials that support use of the drug; recent evidence about ranolazine's therapeutic effect on diastolic heart failure, glycemic control, and atrial fibrillation and other arrhythmias; officially approved clinical indications; and avenues of future study

Hypertension commonly clusters with other cardiovascular risk factors, giving rise to the concept that hypertension is a multifaceted disease that potentially shares common pathogenic pathways with other risk factors. The renin-angiotensin-aldosterone system has a central role in the shared mechanisms of hypertension and cardiovascular disease, primarily through angiotensin II. Increased levels of angiotensin II disrupt the balance of vasoactive substances and growth factors that regulate endothelial structure and function, and inhibition of the renin-angiotensin-aldosterone system with an angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor blocker helps restore this equilibrium. Some pathogenic mechanisms may also be favorably affected by calcium channel blockade. While the relative contribution of pleiotropic effects to clinical benefit is difficult to quantify, based on recent data it is reasonable to consider using newer antihypertensive agents in selected high-risk patients to realize the benefits that may derive from interfering with pathogenic mechanisms of disease