Management of Complex Cardiovascular Problems

Thach N. Nguyen, Dayi Hu, Shao Liang Chen, Moo-Hyun Kim, Cindy L. Grines

• Publisher: Wiley-Blackwell
• Year: 2016
• ISBN:
  9781118965054
• Edition: 4
• Topic: Medicina
• Subtopic: Cardiologia

Patients with complex cardiovascular problems pose a special management challenge for both the specialist and the non-specialist. This book helps you approach difficult cases with the confidence to strategically map care, understand the risk profile of your patient, and make effective treatment decisions.

• Dependable and succinct content provides high yield information for the busy cardiologist
• Take home call outs, and critical thinking boxes provide candid advice on incorporating guidelines and evidence based medicine into your practice
• New convenient pocket-sized format
• New chapter addressing cardiovascular problems in women
• Discussion of high risk factors for and strategic care mapping encourage clinical focus
• Clinical pearls offer expert advice on topical issues
• Includes emerging trends and clinical trials keeping you up to date

CHAPTER 1
Hyperlipidemia

Vien T. Truong, Kim N. Huynh, Tam Ngo, Sara Shah, Hau Van Tran, Chisalu Nchekwube, Nabeel Ali and Faisal Latif

BACKGROUND

Hyperlipidemia – in particular, elevated low-density lipoprotein cholesterol (LDL-C) – is a major risk factor for various forms of cardiovascular (CV) diseases (CVDs). Hyperlipidemia occurs secondary to diet, genetic factors, and/or the presence of other diseases.

CHALLENGES

In the treatment of hyperlipidemia, there are four groups of patients who benefit from statin therapy [1], as listed in Table 1.1. Clinical atherosclerotic CVD (ASCVD) includes acute coronary syndromes (ACS) or a history of myocardial infarction (MI), stable or unstable angina, coronary or other arterial revascularization, stroke, transient ischemic attack (TIA), or peripheral arterial disease (PAD) presumed to be of atherosclerotic origin [1]. The first challenge is for all patients who need to be treated to be identified and treated accordingly. No patient should be left behind without treatment.

Table 1.1 Four statin benefit groups

Patients with clinical atherosclerotic cardiovascular disease. Patients with an LDL-C level of 190 mg/dL or higher without secondary cause. Primary prevention: patients with diabetes, aged 40 to 75 years, or with an LDL-C level of 70 to 189 mg/dL. Primary prevention: patients aged 40 to 75 years with an LDL-C level of 70 to 189 mg/dL and atherosclerotic cardiovascular disease risk estimate of 7.5% or higher.

The second issue is that up to 20% of patients are intolerant to statin therapy due to side-effects [2]. In addition, 5% of patients are resistant to statins [3]. How to treat these patients optimally is the second challenge. The third challenge is to optimize the treatment for the patients not addressed in the American College of Cardiology/American Heart Association (ACC/AHA) guidelines. The fourth challenge is to select the effective management for high triglyceride (TG) or low high-density lipoprotein cholesterol (HDL-C) levels.

STRATEGIC MAPPING

The 2013 ACC/AHA guidelines heralded a radical change in the management of hyperlipidemia, which was a shift in focus from achieving certain numerical targets (LDL-C in particular) to ensuring application of evidence-based dosage of statins shown to improve CV outcomes. The strategy is to identify the patients with hyperlipidemia through a comprehensive history and physical examination. For any adults aged 20 years or older, questions concerning a high-cholesterol diet, obesity in the family, and dietary habits should be asked. Then, a history of atherosclerosis of any major vascular bed should be documented, because this information is very important in classifying patients into a high- or low-risk group. Other medical conditions or the use of drugs causing high cholesterol levels should also be investigated. After these investigations, blood tests are ordered to confirm the diagnosis of hyperlipidemia and its possible etiologies. Once the diagnosis is confirmed, education and treatment may be started, and follow-up results monitored. In the new management strategy, the patients should be involved deeply in the discussion of risks and the decision to start statin therapy. This strategy is to keep treatment not only ‘evidence-based’ but also ‘patient-centered’.

HIGH-RISK MARKERS

According the 2013 ACC/AHA guidelines, ASCVD risks can be calculated by using the new Pooled Cohort Equations for ASCVD risk prediction, developed by the Risk Assessment Work Group [1]. It is a tool to help formulate clinical judgment when there is uncertainty about a patient's risk.

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EVIDENCE-BASED MEDICINE

The ASCVD risk estimator This new risk calculator was derived from four community-based population studies that directly measured risk factors in black and white people free of known CVD at entry, and then recorded heart attack and stroke rates over at least 10 years. Being based on actual observations from contemporary US community cohorts, this new risk estimator reflects the high long-term risk of CVD among black and white Americans [4]. This risk calculator may overestimate the score in Hispanics and East Asians. On the other hand, it does not estimate the risk of angioplasty or hospitalization for unstable angina or TIA, so it underestimates global CV risks. The major components in the risk calculator are listed in Table 1.2 (link for app: www.cardiosource.org/Science-And-Quality/Practice-Guidelines-and-Quality-Standards/2013-Prevention-Guideline-Tools.aspx).

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Table 1.2 High-risk markers in the new ACC/AHA ASCVD risk estimator

Age (range from 20 to 59 years) Race/ethnicity (white or other or African American) Total cholesterol (mg/dL) HDL-C (mg/dL) LDL-C (mg/dL) Systolic blood pressure (mmHg) Blood pressure treated (yes or no) Smoker (yes or no) Diabetes (yes or no) Has ASCVD (yes or no)

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CRITICAL THINKING

Why treat patients with a risk of 7.5%? According to the 2013 ACC/AHA guidelines, a risk of 7.5% or higher is the threshold to be considered for lifestyle and statin therapy because meta-analyses of clinical trials showed statins reduced CV events and strokes in individuals with a risk as low as 5% to less than 10%. While a 7.5% or greater chance of a heart attack or stroke in 10 years does not seem high enough to warrant drug treatment, it is important to recognize that this translates into a cumulative risk of fatal or non-fatal heart attack or stroke of about 22% over 30 years (7.5% for each of three decades) [1].

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Additional high-risk markers

For patients who are not included in the four statin benefit groups given earlier, ...

Table of contents

• Cover
• Title page
• Copyright
• List of Contributors
• Foreword to the Third Edition
• Preface
• Acknowledgements
• CHAPTER 1 Hyperlipidemia
• CHAPTER 2 Hypertension: Implications of Current JNC 8 Guidelines on Treatment
• CHAPTER 3 Stable Coronary Artery Disease
• CHAPTER 4 Acute Coronary Syndrome
• CHAPTER 5 ST Segment Elevation Myocardial Infarction
• CHAPTER 6 Heart Failure (Stages A, B and C)
• CHAPTER 7 Acute Decompensated and Chronic Stage D Heart Failure
• CHAPTER 8 Atrial Fibrillation
• CHAPTER 9 Ventricular Tachycardia
• CHAPTER 10 Syncope
• CHAPTER 11 Aortic Stenosis
• CHAPTER 12 Mitral Regurgitation
• CHAPTER 13 Cardiovascular Problems in Elderly Patients
• CHAPTER 14 Cardiovascular Problems in Women
• Index
• EULA