MNT for Cardiovascular Diseases

Low-Density Lipoproteins (LDL)

Primary transport vehicle for cholesterol in the blood The number and activity of LDL receptors in the liver --> major determinants of LDL in the blood • Without adequate receptors --> increased LDL-cholesterol in the blood --> LDL-cholesterol is oxidized --> deposited in injured areas of arterial wall --> atherosclerotic plaque Receptors = super important; you want more LDL receptors Cholesterol: cell membranes, make hormones (steroids) --> excreted through bile

DASH Diet

Used in the prevention & management of HTN (for those in normal or elevated BP range) Emphasizes: • Fruits (4-5 servings) & vegetables (4-5 servings) • Whole grains: 6-8 servings • Non or low-fat dairy products: 2-3 servings Limits total fat, cholesterol, SFA, sweets • ≤6 oz of meat, poultry, fish (lean choices) • 2-3 servings of ADDED fat/day (margarine, oil, butter) • ≤5 servings of sweets per week 4-5 servings/week of nuts, seeds, legumes • Good sources of Mg -- natural vasodilation properties Combine with 2 g Na

Major Risk Factors for CHD - Non-Modifiable

Age • Male >45 • Female >55 (menopause - less estrogen: estrogen prevents LDL oxidation, lowers LDL, raises HDL) Gender: male > female Hereditary • Positive family history --> parents or siblings (esp. when dx in younger/middle age) • Race --> black

Cardiovascular Disease (CVD)

Disease of the heart and/or blood vessels • Coronary heart disease • HTN • CHF • Cerebrovascular disease • Valvular heart disease • Cardiomyopathy • PVD (narrowed arteries/veins in the periphery - particularly the legs)

Atherosclerosis results in:

Restriction of blood flow: • Coronary heart disease --> MI (if it reaches stage 4) • Cerebrovascular disease --> CVA • PVD --> necrotic foot

Statistics for CHD a.k.a CAD

16.5 million Americans Highest prevalence: Black women • Black men • White men • White women Lowest prevalence: Asian women

High Sodium Foods

>300 mg Na/serving • Processed or cured meats & fish --> ham, bacon, cold cuts, hot dogs, sausage, sardines • Tomato juice • Salted snacks • Canned soup • Canned beans - rinse! • *Processed* cheese & cheese spreads • Many condiments: soy sauce, BBQ sauce, ketchup, pickles • Prepackaged frozen foods; packaged mixes for rice, potato, pasta dishes

Factors that decrease HDL

Abnormally low HDL levels • Obesity • Physical inactivity • Smoking • Genetic factors • Cirrhosis

Secondary HTN

Caused by another disease/issue; can be cured most of the time

Metabolic Syndrome

Clustering of CHD risk factors. Diagnosed by having ≥3 of the following: • Abdominal obesity: WC >40 in for men/>35 in for women • TG ≥150 mg/dl • HDL <40 mg/dl for men & <50 mg/dl for women • Glucose intolerance: FBG ≥100 mg/dl (pre-diabetes range and up) • Blood pressure: ≥135/≥85 mmHg (stage 1 HTN and up)

Diet Recommendations for Lowering LDL

Consume a dietary pattern that: • emphasizes intake of vegetables, fruits & whole grains (micronutrients, phytonutrients, antioxidants, soluble fiber) • includes low-fat dairy products, poultry, fish (omega-3s lower TGs), legumes, non-tropical vegetables oils (avoid: palm, palm kernel, coconut) & nuts • limits red meats, sweets, sugar-sweetened beverages

Regulation of BP: SNS

Decreased BP --> SNS --> Norepi --> vasoconstriction --> increased PR --> increased BP

Diagnosis of CHD

Definitive test --> Cardiac catheterization • Fluoroscopic images of the heart & coronary arteries • Visualize narrowing & blockages

Diuretics

Facilitate renal *excretion of Na & H2O* --> decrease blood volume --> decrease CO Thiazide diuretics (hydrochlorothiazide) - primary tx & Loop diuretics (furosemide) - secondary tx -- more powerful. DNI: • *Increase urinary K excretion --> hypokalemia* • Increase Mg excretion • Can increase serum glucose and lipid levels • Rx low Na, low kcal (if need to lose wt), high K & Mg diet (to get DRI) Potassium-sparing diuretics (Spironolactone) - less commonly used; use to avoid hypokalemia • Can increase K --> sometimes leads to hyperkalemia; need to ensure pt is not on a K supplement, avoids excessive K intake and using KCl as salt substitute • Can increase LDL & decrease HDL • Rx low Na & low kcal diet

HTN

HTN is caused by chronic increased cardiac output, increased *peripheral resistance*, or both Constant stimulation instead of only when needed Peripheral resistance: resistance to blood flow in the arteries • Too much constriction • More common

Treatment of Metabolic Syndrome

Treat underlying conditions/risk factors: • Weight management • Physical activity • Treat dyslipidemia (provide specific MNT) • Improve BG control (CHO control) • Reduce BP levels (MNT for HTN) • Reduce TG levels (try to eliminate alcohol, moderate CHO diet, decrease sat+trans fats)

Atherosclerosis: 3. Fibrous Plaque

Fibrous tissue & smooth muscle cells form a fibrous cap over the foam cells (scab forms over lesion)

MNT Post-MI

Immediate -- Cardiac Diet: • Reduce saturated fat and trans fat • Reduce sodium - 2g/d even if person doesn't have HTN; trying to decrease the work of the heart/keep BP low • Avoid caffeine - specifically for dysrhythmias Long-term: • Heart healthy diet - for life • Risk factor reduction - refer to outpt RD to lose wt if needed

Nutrition Goals for Hyperlipidemia &/or CHD

Improve serum lipid levels: • *Reduce intake of saturated fat to 5-6% of total kcal* & replace with PUFA + MUFA -- lowers both LDL + TGs • Reduce intake of trans fatty acids (beef, pork, milk fat) • Increase soluble fiber (F/V) intake (lowers LDL by binding to bile acids and excreting through feces) • Increase physical activity to 3-4x/week of 40 mins of moderate to vigorous intensity (ANY physical activity is helpful) Achieve & maintain a healthy body weight

Total Cholesterol

Measure of cholesterol contained in all lipoproteins • Fairly good indicator of LDL levels: 60-70% is carried on LDL Direct positive relationship to CHD (the higher the number = higher the risk) Normal finding: <200 mg/dl

Lipid Lowering Medications: HMG-CoA Reductase Inhibitors

Lovastatin, pravastatin, atorvastatin • Decrease *LDL*, TG and increase HDL • Side effects: liver function abnormalities (rare complication of muscle damage) • Food drug interaction: avoid grapefruit and grapefruit juice - inhibits metabolism so drug can reach toxic levels (72 hour interaction) Decreases liver's production of LDL (in particular), TG and slightly increases HDL Thought to be the most effective pharmacological treatment

Atherosclerosis: 2. Fatty Streak

Macrophages engulf oxidized LDL and penetrate the endothelium (Stay @ the site of endothelial injury) Factors that promote LDL oxidation: • HTN • Smoking (nicotine) • DM (glucose in the blood)

Tx Post-MI

Medications including: • Morphine • Beta-blockers - block action of catecholamines on the heart; allows heart to rest: slows down HR, lowers BP • Anti-arrhythmic agents - for dysrhythmias • Thrombolytic agents - break up clots • ACE-inhibitors - lower BP Oxygen therapy Bed rest with gradual return to ADLs; outpt cardiopulmonary rehab (supervised exercise) Possible coronary angioplasty or CABG

Coronary Heart Disease (CHD)

Narrowing or blockage (from plaque) of the small blood vessels that supply blood and oxygen to the heart • Caused by atherosclerosis • Happens mostly in coronary arteries

HTN - 2017 BP Classifications

Normal • Systolic -- <120 mmHg • Diastolic -- <80 mmHg Elevated • Systolic 120-129 mmHg • Diastolic <80 mmHg HTN: Stage 1 • Systolic -- 130-139 mmHg • Diastolic -- 80-89 mmHg HTN: Stage 2 • Systolic -- ≥140 mmHg • Diastolic -- ≥90 mmHg Hypotension • Systolic -- <90 • Diastolic -- <60

HDL-Cholesterol Levels

Normal findings: Female: >55 mg/dL Male: >45 mg/dL ≥80 mg/dL is too high - no longer protective

TG Levels

Normal: <150 mg/dL Borderline high: 150-199 mg/dL High: 200-499 mg/dL Very high: ≥500 mg/dL -- probably have genetic hyperlipidemia; lifestyle changes alone will not help; also at increased risk for acute pancreatitis

Atherosclerosis: 4. Complicated Lesion

Plaque ruptures --> platelets aggregate --> thrombus --> vessel occlusion If this happens in a coronary artery --> MI If in carotid artery --> can cause stroke

Atherosclerosis: 1. Endothelial Injury

Platelets adhere and release growth factors that promote lesion development; Macrophages adhere Injury caused by: • Dyslipidemia (higher LDL, lower HDL) • HTN • Smoking (nicotine) • DM (higher amount of glucose in blood) • Hyperhomocysteinemia • Increased C-reactive protein & fibrinogen (inflammatory) • Oxidative stress (oxidated LDL)

Serum Triglycerides (TG)

Positive correlation between high TG and CHD risk

Myocardial Ischemia

Precursor to MI • Insufficient blood supply to the myocardium • Most common cause --> atherosclerosis • Myocardial cells become ischemic after 10 seconds (decreased contraction); can remain viable for ~20 minutes • Symptom = angina pectoris --> if recurrent episodes: rx: nitroglycerin (NGT; taken sublingual); vasodilator --> hopefully clot with break up on its own If cells do not have enough oxygen to do Kreb's cycle --> Glycolysis (anaerobic) --> produces lactic acid --> PAIN (angina)

Myocardial Infarction (MI)

Prolonged ischemia (>20 minutes) that causes *irreversible* damage to the heart muscle Caused by: • *Atherosclerosis* --> complicated lesion --> thrombus --> vessel occlusion (by platelets aggregating at spot of rupture of plaque) • Vasospasms --> arteries temporarily clamp shut; no MNT, usually on vasodilators

High-Density Lipoproteins (HDL)

Removes cholesterol from the arterial wall and transports to the liver High levels are protective; low levels are a risk factor for CHD

LDL-Cholesterol Levels

Truly optimal: <100 mg/dL Normal finding: <130 mg/dL High: 130-190 mg/dL • Tx = MNT Very high: ≥190 mg/dL • Could be a genetic disorder: few LDL receptors or receptors don't work

Coronary Artery Bypass Graft (CABG)

Surgery --> a vein from the leg or artery from the chest is used to redirect blood flow around a diseased vessel (usually on ICU on vent 1-2 days post op) Bypass a blocked artery and deliver oxygen to the heart; One end of the blood vessel is attached to the aorta; Other end is attached to the coronary artery at a point below the blockage New grafts are susceptible to atherosclerosis -- still only temporarily fixing the problem; need to change risk factors/lifestyle (unless genetic) MNT: • Increased kcal & protein post-op for healing (SF = major surgery) • Heart healthy diet - for whole life

Atherosclerosis

Thickening & narrowing of blood vessel walls caused by the invasion of cholesterol & fibrin into the endothelium to form plaque • An inflammatory & proliferative response to wall injury • Pathogenesis is multi-factorial

Factors that increase TG

• Wt gain; obesity • Sedentary lifestyle • Excess alcohol intake • High CHO diet (>60% of kcal from CHO) • Poorly-controlled DM • Genetic disorders • Pregnancy (often temporary) • HIV-associated lipodystrophy • Meds: corticosteroids

Factors that increase LDL

• *Diet: high in saturated fat and trans-fatty acids* (decrease the activity of LDL-receptors) • Genetics • Weight gain; Obesity • Hypothyroidism • Biliary obstruction - bile ducts are only way to excrete LDL • Nephrotic syndrome • Meds: diuretics, cyclosporine, corticosteroids

Essential or Primary HTN

• 90-95% of pts with HTN • Unknown cause -- multifactorial, complex interaction between lifestyle factors + gene expression (like issues with regulation of BP) • No cure - chronic Goal = get BP as close to normal as possible

Recommended Diet Patterns

• AHA diet • DASH diet • Mediterranean diet (esp. good for high TGs)

Pathophysiology of MI

• Cellular death of myocardial cells occurs after 20 minutes • Functional changes --> decreased contractility (wherever the MI is happening); decreased ejection fraction (decreased amount of blood leaving the heart with each contraction) • Repair --> inflammation; formation of scar tissue (that part of the heart is never the same)

Major Risk Factors: Modifiable

• Cigarette smoking • High LDL-cholesterol • HTN • DM • Obesity (causes a bunch of these risk factors itself) • Physical inactivity (people may not know this) • Low HDL-cholesterol • High TG • Excessive alcohol consumption • Stress

Regulation of BP: Kidneys

• Control extracellular fluid volume by adjusting urine output • Decreased BP --> decreased blood flow to kidney --> renin --> angiotensin I --> *angiotensin II* --> vasoconstrictor (of arterioles and capillaries) and stimulates the release of *aldosterone* --> increased sodium reabsorption (increase volume of blood) --> increased BP Increased BP: • Increased blood volume • Vasoconstriction

Drugs Used in the Management of HTN

• Diuretics • Calcium channel blockers (diltiazem) • Angiotensin converting enzyme (ACE) inhibitors (captopril) • Angiotensin receptor blockers (losartin)

Post-MI Complications

• Dysrhythmias -- Afib, Vfib, Vtach; catecholamines leak out of ruptured myocardial cells, loss of electrolytes, lactic acid • If blockage on left side (L coronary artery) & the L ventricle is damaged --> Left ventricular failure --> CHF • Sudden cardiac death = w/in 2 hours of onset of Sx --> ventricular fibrillation = heart is just quivering

Additional Risk Factors

• Elevated C-reactive protein • Elevated fibrinogen levels (precursor to fibrin) • Elevated homocysteine levels (caused by a deficiency of B12, folate, B6 or genetics; lower risk factor/weak)

2g Na Diet

• Eliminate salt at the table and decrease in food preparation (can cut salt in recipes in half or even more) • Eliminate high sodium foods (*>300 mg Na/serving*) -- for starters, reduce these • Reduce intake of processed foods • Use low sodium canned & instant products

Lifestyle Management for Hyperlipidemia &/or CHD

• Emphasis on a heart healthy diet, achieving and maintaining a healthy weight, increased physical activity and no smoking • Focus has shifted from the role of individual nutrients to dietary patterns and their relationship to CVD

Lifestyle Modifications Used in Prevention & Tx of HTN

• Weight management/reduction • *Lower sodium intake ≤2400 mg/d* AT MAX; any decrease is going to be beneficial • DASH diet: Diet rich in vegetables, fruits, whole grains; includes low fat dairy products, poultry, fish, legumes, non-tropical vegetable oils & nuts; limits intake of sweets, sugar-sweetened beverages and red meat • Limit alcohol to ≤2 drinks/d for men & ≤1 drink/day for women; 1 drink = 12 oz beer, 5 oz glass of wine, 1.5 oz liquor • Increase physical activity: engage in aerobic PA at least 3-4x/week, 40 mins per session, moderate to vigorous intensity (any is better than none) • Stop smoking

ACE Inhibitors

• Inhibit angiotensin-converting enzyme --> decrease production of angiotensin II & aldosterone • Results in decreased Na & H2O retention (aldosterone); decreased vasoconstriction (angiotensin II) • Examples: captopril, lisinopril DNI: • Can increase serum K --> avoid salt substitutes; ask pt about K supplementation • Rx low Na, low kcal diet

Risk factors for Primary HTN

• Older age - 1/2 of adults over age 65 have HTN (probably d/t lifestyle) • Family hx & genetic factors • Ethnic background --> African American (genes, lifestyle or both) • Overweight/Obese • Physical inactivity • Excessive sodium consumption • Excessive alcohol consumption • Low intake of potassium (vasodilator) -- excrete Na better if you have K in body • Smoking -- nicotine = vasoconstrictor

Coronary Angioplasty

• Percutaneous coronary intervention (PCI) • Uses a balloon catheter to break up plaque and dilate a stenotic artery • Stent -- same procedure but it's a coil and it is left in there to hold the artery open • Most common problem --> restenosis of artery (pt needs to change their risk factors) • MNT --> Heart Healthy Diet (AHA, DASH) This is a temporary solution; does not cure the problem

Role of Lifestyle Modifications in Management of Primary HTN

• Prevent development of HTN for those in the "elevated" BP range - primary prevention! • Can control BP in mild HTN • Enhances the effects of drug therapy • Can decrease other CVD risk factors

Coronary Arteries

• Provide blood and oxygen to the actual heart • Worst place for occlusion: top left of CA before it splits -- "widow maker"

Nutrition Education for HTN

• Rationale for diet guidelines • DASH + 2 g Na diet -- dietary sources, recommended servings, label reading • Weight loss strategies - portion control, exercise • Alcohol intake • PA • DNI

Implementation: Diet Education

• Rationale for lifestyle modifications "Could help improve your risk factors" • Definitions & food sources of: saturated vs. unsaturated fat, trans fat, soluble fiber, etc. • Role of certain food groups in increasing/decreasing lipid levels • Foods recommended; Foods to limit • *Strategies to reduce intake of SFA & trans-fatty acids* -- decrease fat in dairy/portion control; leaner cuts of meat: "round" or sirloin, leanest ground beef • Importance of portion control (esp. for those with weight issues) • Weight reduction if needed • Increased physical activity • Label reading • Food-drug interactions • Additional diet restrictions if needed (often have more than one medical issue, like HTN)

Sodium Labeling

• Sodium free: <5mg Na/serving • Very low sodium: ≤35 mg Na/serving • *Low sodium: ≤140 mg Na/serving* • Reduced sodium: at least 25% less Na than in the regular food (ex. reduced sodium soy sauce is still 500 mg Na/T) • Light in sodium: 50% less Na than in the regular food • Unsalted, without salt or no added salt: no NaCl added during processing

Symptoms of MI

• Sudden severe chest pain -- not relieved by NTG -- if person has angina, the pain is MUCH worse • Pain may radiate to the neck, jaw, back, shoulder or left arm -- irritated nerve fibers (referred pain) • N/V • Diaphoresis Women feel these sx differently/may not present with common sx

Manifestations & Complications of HTN

• Uncomplicated HTN --> asymptomatic - initially • Dizziness, flushing, HA, edema (BLE d/t hydrostatic pressure) • Atherosclerosis --> CHD • Left ventricular hypertrophy - L ventricle wears out over the years --> CHF • Cerebrovascular --> CVA - pressures cause blood vessels to burst in the brain • Peripheral vascular disease (PVD) • Aneurysm - weakened artery walls that can balloon-out and rupture • Nephropathy - HTN = 2nd most common cause of ESRD (DM is #1) • Retinopathy - blindness d/t damaged capillaries from high pressure

Factors that increase HDL

• Weight loss (if the person is obese) • Exercise • Moderate (1/d women; 2/d men) consumption of alcohol - thins blood, antioxidants/ phytonutrients; however, increases TG

MNT for Hypertriglyceridemia

• Weight loss (if they have a weight issue) • Increase physical activity • Consume moderate (not high) amounts of CHO; Limit added sugars -- education! • Implement Mediterranean-style diet (seeds/nuts/olive oil, polys/monos, 30-35% kcal from fat, more omega-3s) • Decrease intake of saturated fat • Eliminate dietary trans fatty acids • Restrict alcohol use • Increase dietary intake of marine-derived omega-3 fatty acids (fish > flax seed oil, canola oil) • Management of DM • Lipid lowering drugs if necessary (e.g. gemfibrozil) NCM --> High TG Nutrition Therapy