Cardiovascular Medicine Book

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Systolic DysfunctionAka: Left Ventricular Dysfunction, Left Ventricular Failure, Systolic Heart Failure, Dilated Cardiomyopathy

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  1. See Also
    1. Heart Failure
    2. Diastolic Dysfunction
  2. Causes
    1. Coronary Artery Disease is most common cause
    2. See Heart Failure Causes
  3. Mechanism (with associated symptoms)
    1. Decreased filling pressure (congestion)
      1. Increased left sided pressure: Dyspnea
      2. Increased right sided pressure: Edema, Ascites
    2. Decreased cardiac output
      1. Fatigue
      2. Depression
  4. Symptoms
    1. Early symptoms
      1. Decreased Exercise tolerance
      2. Dyspnea on Exertion
        1. Test Sensitivity: 100%
        2. Test Specificity: 17%
          1. See Dyspnea Causes
    2. Later symptoms
      1. Paroxysmal Nocturnal Dyspnea
        1. Not sensitive or specific for CHF
      2. Orthopnea
      3. Unexplained confusion or lethargy (often in elderly)
      4. RUQ Abdominal Pain or fullness, early satiety
        1. Hepatic engorgement
        2. Ascites
    3. Non-specific symptoms
      1. Weight gain
      2. Fatigue
    4. Lower extremity edema (often Dependent edema)
      1. Venous Insufficiency
      2. Lymphedema
  5. Past Medical History
    1. See Heart Failure Causes
    2. Prior Myocardial Infarction
    3. Hypertension
    4. Valvular heart disease
    5. Cardiotoxins
    6. Confounding factors
      1. Medications
        1. Beta Blocker
        2. Calcium Channel Blocker
      2. Alcohol Abuse
      3. Drug Abuse
      4. Thyroid disease
      5. Hepatic disease
      6. Renal disease
  6. Signs
    1. S3 Gallop Rhythm
      1. Most specific CHF indicator over age 40
        1. Test Sensitivity: 24%
        2. Test Specificity: 99%
      2. CHF patients (n=19) with Ejection Fraction <30%
        1. S3 Gallop present in 68% of these patients
      3. Reference
        1. Mattleman (1983) J Am Coll Cardiol 1(2):417
    2. Elevated Jugular Venous Distention (highly specific)
    3. Laterally displaced apical impulse (highly specific)
    4. Pulsatile Liver
    5. Rales (nonspecific)
      1. Do not clear with cough
      2. Not sensitive or specific for CHF
    6. Lower extremity edema
      1. Not attributable to Dependent edema
      2. Not sensitive or specific for CHF
    7. Pulsus alternans
      1. Tachycardia accompanied by low volume pulse
    8. Poor perfusion
      1. Poor capillary refill
      2. Cool distal extremities
      3. Altered mental status
  7. Labs
    1. Complete Blood Count (CBC)
    2. Chemistry panel (Chem7, SMA7)
      1. Electrolyte abnormality
      2. Renal insufficiency
    3. Urinalysis
    4. B-Type Natriuretic Peptide (BNP) >150
      1. Sensitive and specific marker for CHF
    5. Serum Albumin
      1. Nephrotic Syndrome
    6. Thyroid Stimulating Hormone (TSH) indicated for
      1. Over age 65
      2. Atrial Fibrillation
    7. Urine Toxicologic screen
      1. If Cocaine abuse suspected
  8. Diagnostics: Basic
    1. Chest XRay
      1. Findings suggestive of CHF
        1. Cardiomegaly
        2. Pulmonary venous congestion
        3. Efficacy
          1. Test Sensitivity: 71%
          2. Test Specificity: 92%
      2. Other findings
        1. Underlying lung disease
        2. Chamber enlargement
        3. Valve calcifications
    2. Electrocardiogram (EKG)
      1. Findings suggestive of CHF
        1. Anterior Q waves
        2. Left Bundle Branch Block
        3. Efficacy
          1. Test Sensitivity: 94%
          2. Test Specificity: 61%
      2. Other findings
        1. Ventricular hypertrophy
        2. Atrial enlargement
        3. Conduction abnormality
        4. Arrhythmia
        5. Prior Myocardial Infarction
        6. Active ischemia Myocardial Ischemia
  9. Diagnostics: Advanced
    1. Echocardiogram in CHF
      1. Indicated in every Congestive Heart Failure patient
      2. Ejection Fraction 40% or less
      3. Other factors evaluated
        1. Chamber size and shape
        2. Wall thickness
        3. Valvular function
    2. Evaluation for Ischemic Heart Disease
      1. Modalities
        1. Exercise Stress Testing
        2. Nuclear (Thallium or Cardiolyte-Technetium)
        3. Cardiac catheterization
      2. Observe for reversible ischemic changes
        1. Consider Angioplasty (PTCA)
        2. Consider Coronary Artery Bypass Graft (CABG)
    3. Ambulatory rhythm monitor (Holter Monitor)
      1. Observe for ventricular arrhythmia
      2. Consider patient for Implantable Defibrillator
  10. Diagnosis
    1. Sensitive CHF markers (if absent, CHF is unlikely)
      1. Dyspnea on exertion
      2. EKG with anterior Q Waves or Left Bundle Branch Block
      3. B-Type Natriuretic Peptide (BNP) <50 pg/ml
    2. Specific CHF markers (if present, suggest CHF)
      1. Displaced Cardiac Apex on palpation
      2. S3 Gallup Rhythm
      3. Jugular Venous Distention
        1. With or without hepatojugular reflex
      4. Chest XRay with cardiomegaly or vascular congestion
    3. References
      1. Dosh (2004) Am Fam Physician 70:2145
        1. Also cited for efficacy under signs and symptoms
  11. Management: General Measures
    1. Limit salt intake: 2-3 gram Sodium Diet (no added salt)
    2. Graded Exercise program
      1. Reduces Heart Failure related mortality
      2. Piepoli (2004) BMJ 328:189
    3. Control comorbid conditions
      1. Hypertension
      2. Coronary Artery Disease
      3. Diabetes Mellitus
      4. Obstructive Sleep Apnea
      5. Major Depression
    4. Avoid Provocative Medications
      1. Avoid Nonsteroidal Anti-inflammatory drugs (NSAIDS)
        1. Block ACE Inhibitors
        2. Block Diuretics
      2. Avoid Calcium Channel Blockers (except Amlodipine)
      3. Avoid beta agonists unless absolutely indicated
        1. Higher hospitalization and mortality rates in CHF
        2. Au (2003) Chest 123:1964
      4. Avoid ARB with ACE Inhibitor and Beta Blocker
        1. Valsartan plus ACE Inhibitor showed no benefit
        2. Valsartan + ACE + Beta Blocker increased mortality
        3. Cohn (2001) N Engl J Med 345:1667
    5. Stop habits associated with hospital readmission
      1. Tobacco Cessation
      2. Alcohol cessation
    6. Establish target Ideal Weight (not dry weight)
      1. Assess for too dry (Orthostatic Hypotension)
        1. Monitor standing Blood Pressure in clinic
        2. Evaluate Renal Function tests for Azotemia
      2. Assess for too wet
        1. No Orthopnea
        2. No paroxysmal nocturnal Dyspnea
      3. Assess for maintenance of Ideal Weight
        1. Follow daily weight at home with weight diary
        2. Report weekly weight gain 3-5 lb (1.5 - 2.0 kg)
        3. Patient may adjust their lasix at home (see below)
    7. Sliding scale Diuretics (uses daily weights)
      1. Based on weight variation from maintenance weight
      2. Weight gain 1-3 pounds: No change to Diuretic dose
      3. Weight gain 3-5 pounds: Take extra Diuretic dose
      4. Weight gain >5 pounds: Call clinic nurse immediately
  12. Management: Medications
    1. See Acute Pulmonary Edema Management
    2. Overall protocol (starting dosing listed)
      1. Step 1: Loop Diuretic: Lasix 20-40 mg PO 1-2x/day
      2. Step 2: ACE Inhibitor: Lisinopril 2.5 mg PO daily
      3. Step 3: Beta Blockers: Metoprolol XL 12.5 mg PO daily
      4. Step 4: Add adjunct (choose one line)
        1. Angiotensin Receptor Blocker: Losartan 25 mg qd or
        2. Aldosterone Antagonist: Spironolactone 12.5 mg qd or
        3. Hydralazine with Isosorbide
      5. Step 5: Add Digoxin
    3. Primary Medical Management (Class I, II, III)
      1. ACE Inhibitor (most important agent in CHF)
        1. See ACE Inhibitor in CHF for management protocol
        2. See ACE Inhibitor in CHF for alternative agents
          1. Angiotensin-receptor blocker is alternative
        3. Consider adding Spironolactone early (see below)
          1. Blocks aldosterone escape from ACE Inhibitor
      2. Beta Blocker
        1. Protocol
          1. Avoid in decompensated CHF (start when stable)
          2. Start with low doses
          3. Titrate doses slowly (double dose q2-4 weeks)
          4. Evaluate worse Dyspnea, failure or hypotension
            1. Decrease or discontinue Beta-Blocker dose
            2. Consider increasing Diuretic dose
          5. Expect initial drop in ejection fraction
            1. Patients will feel more Fatigued in first month
            2. Beta Blocker benefits realized by 3 months
        2. Agents
          1. Metoprolol (Lopressor)
            1. Toprol XL
              1. Start at 12.5 to 25 mg qd (max: 200 mg/day)
          2. Bisoprolol (Zebeta)
            1. Start: 1.25 mg daily (maximum: 10 mg/day)
          3. Carvedilol (Coreg)
            1. Start at 3.125 mg bid
            2. Slowly titrate to 12.5 - 25 mg bid over 2 weeks
            3. Superior to Metoprolol in increasing Ejection Fraction
              1. Raiput (2003) Am J Cardiol 92:218
        3. Outcomes
          1. Safe and well tolerated even in Class IV CHF
          2. Reduces mortality and hospitalization rates
          3. Improved CHF related symptoms
          4. Goldstein (2001) J Am Coll Cardiol 38:932
    4. Relief of Congestive Heart Failure symptoms
      1. Diuretics (reduce volume overload)
        1. First Line: Loop Diuretics
          1. Use as adjunct to other drugs above
          2. Diuretics are not the primary CHF treatment
          3. Start Furosemide 20-40 mg PO daily to bid
        2. Second: Spironolactone or Eplerenone (Aldosterone Antagonists)
          1. NYHA Class III or IV
          2. Serum Creatinine must be <2.5 mg/dl (GFR > 50 ml/minute/1.73m2)
          3. Serum Potassium must be normal (<5.5 meq/L)
          4. Bozkurt (2003) Am J Cardiol 41:211
      2. Digoxin (Increased contractility)
        1. Typical dose: 0.125 mg daily (up to 0.25 mg daily)
          1. Decrease to 0.0625 if drug interactions or Chronic Renal Insufficiency
        2. Does not decrease mortality, but significantly improves quality of life
        3. Increased mortality if serum Digoxin >1.0 ng/ml
          1. Keep serum Digoxin level 0.5 to 0.8 ng/ml (measure 6-8 hours after dose)
          2. Rathore (2003) JAMA 289:871
        4. May be associated with increased mortality in women
          1. Rathore (2002) N Engl J Med 347:1403
    5. Consider Additional Management
      1. Coronary revascularization (e.g. PTCA) if ischemia
      2. Atrial Fibrillation treatment if present
      3. Cardiac resynchronization
        1. Indications
          1. Ejection fraction >35% and
          2. QRS Duration >120 ms and
          3. Symptomatic despite maximal medical therapy
        2. Efficacy
          1. Reduces mortality and hospitalization rate
          2. Pacemaker with Defibrillator was most effective
        3. References
          1. Bristow (2004) N Engl J Med 350:2140
          2. McAlister (2004) Ann Intern Med 141:381
      4. Implantable Defibrillator
        1. May be indicated in NYHA Class 2-3 with EF<35%
        2. Reduces mortality (Amiodarone does not)
          1. Bardy (2005) N Engl J Med 352:225
      5. Coumadin
        1. Aspirin is a reasonable alternative
        2. Indicated for arrhythmia
        3. Indicated for thromboembolism risk
        4. Not indicated in standard cardiomyopathy
        5. No data to support use in low ejection fraction
      6. Eplerenone (Inspra)
        1. Mechanism: Aldosterone blockade
        2. Effective in CHF from acute Myocardial Infarction
        3. Alternative to Spirinolactone, but much more expensive
          1. Does not warrant additional cost in most cases
          2. Consider if severe Gynecomastia on Spironolactone
        4. References
          1. Pitt (2003) N Engl J Med 348:1309
      7. Tolvaptan
        1. Mechanism: Vasopressin Receptor Antagonist
        2. Reduces volume overload and congestion immediately
        3. Appears to have longterm benefit in CHF
        4. Gheorghiade (2004) JAMA 291:1963
      8. Hydralazine and Isosorbide Dinitrate
        1. Especially effective in younger black patients
        2. Start
          1. Hydralazine 12.5 mg PO and
          2. Isosorbide Dinitrate or Isosorbide Mononitrate
            1. Dinitrate 5-10 mg tid with 12 hour-free or
            2. Mononitrate 30 mg qd
        3. Maintenance
          1. BiDil 37.5/20 1 po tid (max 2 tid) or
          2. Hydralazine 37.5-75 mg/day and Dinitrate 20-40 mg
      9. Nesiritide (Natrecor)
        1. Recombinant Human Brain Natriuretic Peptide
        2. Results in venous and arterial vasodilation
        3. Dosing
          1. Bolus: 2 mcg/kg IV bolus
          2. Maintenance: 0.01 mcg/kg/min for 24-48 hours
        4. Improves CHF symptoms but may increase mortality
        5. Sackner-Bernstein (2005) JAMA 293:1900
  13. Management: Based on Heart Failure Classification
    1. Asymptomatic (NYHA Class I)
      1. ACE Inhibitor in CHF
      2. Beta Blocker
    2. Symptomatic (NYHA Class II and IIIa)
      1. ACE Inhibitor in CHF
      2. Beta Blocker
      3. Diuretic
      4. Consider Digoxin if symptoms persist despite above
    3. Symptomatic with recent rest Dyspnea (NYHA Class IIIb)
      1. ACE Inhibitor in CHF
      2. Beta Blocker
      3. Diuretic
      4. Spironolactone (Aldactone) or Eplerenone
      5. Digoxin
    4. Symptomatic with Dyspnea at rest (NYHA Class IV)
      1. ACE Inhibitor in CHF
      2. Diuretic
      3. Spironolactone (Aldactone) or Eplerenone
      4. Digoxin
  14. Management: Refractory CHF
    1. Indicated for lack of response to above measures
    2. Assumes ACE Inhibitors and Beta Blockers above
    3. Step 1: Loop Diuretic
      1. Double dose (not twice daily) if no response
      2. Double dose if Serum Creatinine remains >2.0
    4. Step 2: Add second Diuretic with caution
      1. Thiazide Diuretic
      2. Spironolactone (offers aldosterone blockade)
        1. Dose: 25 mg qd
        2. Indicated in Class III or Class IV CHF
        3. Contraindicated if Serum Creatinine >2.5 mg/dl
        4. Alternative: Eplerenone
      3. Metolazone (Zaroxolyn)
        1. Dose 5-10 mg twice weekly 1 hour before lasix
    5. Step 3: Add Hydralazine and Nitrates
    6. Step 4: Loop Diuretic IV
    7. Step 5
      1. Dobutamine with low dose Dopamine
        1. Intermittent Dobutamine reduces mortality
        2. Nanas (2004) Chest 125:1198
      2. Consider Milrinone
    8. Step 6
      1. Consider for Revascularization if indicated
      2. Consider for Cardiac Transplantation
  15. Prognosis
    1. Congestive Heart Failure Exacerbation Decision Rule
    2. Six-Minute Walk Test
      1. Predicts mortality and hospitalization
    3. Survival for Hypertensive Heart Failure
      1. Men: 24% five-year survival
      2. Women: 31% five-year survival
  16. References
    1. Ryan (2001) CMEA Internal Medicine Lecture, San Diego
    2. Chavey (2001) Am Fam Physician 64(5):769
    3. Chavey (2001) Am Fam Physician 64(6):1045
    4. Evangalista (2000) Am J Cardiol 86:1339
    5. Hoyt (2001) Am Fam Physician 63(8):1593
    6. Jessup (2003) N Engl J Med 348:2007
    7. Senni (1997) Mayo Clin Proc 72:453
    8. Whorlow (2000) Am J Cardiol 86:886
    9. (1999) J Card Fail 5:357
    10. (1997) N Engl J Med 336:525
    11. (1996) JAMA 275(20):1549
    12. (1995) Circulation 92:2764

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