27 August 2009

Angioedema



Angioedema

Overview
* Self-Limited, subcutaneous edema resulting from increased vascular permeability
* Generally resolves over 24-48 hours
* Mast Cell / Kinin related etiologies
* Involvement of the lips, pharynx and bowel common (potentially life-threatening)
* Treated with CCS and H1/H2 blockers

Etiology
* Immunologic / IgE mediated
* Hereditary and Acquired (non-mast cell)
Ace-Inhibitors
* ACE (Kininase II) degrades bradykinin
* ACE-I results in inc levels bradykinin
* Pts with genetic deficiencies in bradykinin degradation could be at higher risk
* 0.1-0.7% of patients tx with ACE-I
* Intestinal edema may develop

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Congestive Heart Failure



Congestive Heart Failure
By:Chris Hague, PhD
Technical Advisor: Seth Goldenberg, PhD

Outline

1. What is congestive heart failure?
2. Cardiac Glycosides
3. Phosphodiesterase inhibitors
4. Beta-adrenergic receptor antagonists
5. Sympathomimetics
6. ACE inhibitors/angiotensin receptor antagonists
7. Vasodilators
8. Diuretics
9. Aldosterone antagonists

Congestive Heart Failure
Patient Classification
* Class I (asymptomatic)
* Class II (mild)
* Class III (moderate)
* Class IV (severe)

Factors contributing to CHF
* Ischemic Heart Disease: most prevalent
* CAD: less blood flow to heart, increased damage
* Myocardial Infarct: damaged tissue
* Hypertension: “overworked” heart
* Diabetes
* Lung Disease
* Cardiomyopathies: heart muscle disease
o dilated - enlarged chambers (ventricle/atria)
o hypertrophic - thickened ventricle walls
* Abnormal heart valves: inefficient pumping
o causes are genetic, infection or disease
* Congenital heart defects: present at birth
* Severe Anemia
* Hyperthyroidism
* Cardiac Arrhythmia

Effect on Cardiac Output
Overall decrease in Frank-Starling curve with CHF
Examples of CHF factors
Hypertrophic Cardiomyopathy
Congenital Heart Defects
Types of Heart Failure

* include left, right or both sides
* left ventricular heart failure
* right ventricular heart failure
Onset of disease

* chronic disease: can take years to develop
* endogenous compensatory mechanisms

Compensatory Mechanisms
Symptoms of CHF
* shortness of breath
* persistent coughing/wheezing
* edema (or excess fluid buildup in body tissues)

Symptoms of CHF
* tiredness/fatigue
* lack of appetite/nausea
* confusion/impaired thinking
* increased heart rate

Problems
* Reduced force of contraction
* Decreased cardiac output
* Increased TPR
* Inadequate organ perfusion
* Development of edema
* Decreased exercise tolerance
* Ischemic heart disease
* Sudden death

Therapeutic Overview
Goals
* alleviate symptoms
* improve quality of life
* arrest cardiac remodeling
* prevent sudden death
Drug
* Chronic heart failure
o ACE inhibitors
o Beta-blockers
o ATII antagonists
o aldosterone antagonists
o digoxin
o diuretics
* Acute heart failure
o diuretics
o PDE inhibitors
o vasodilators

Therapies
Non-drug
* Reduce cardiac work
* Rest
* Weight loss
* low Na+ diet
Cardiac Glycosides
* discovered by William Withering
* published “An Account of Foxglove and some of Its Medical Uses” in 1785
* Foxglove plant
Cardiac Glycosides
* derived from plants
o Strophanus - Ouabain
o Digitalis lanata - Digoxin, Digitoxin
* increase force of myocardial contraction
* alters electrophysiological properties
* toxic side-effects
* Digoxin most common used in USA

Digitalis lanata
Mechanism of Action
* inhibitor of Na+/K+ ATPase pump
* increased [Na+]i
* increased Ca2+ influx through Na+/Ca2+ exchanger
* new Ca2+ steady-state: increased Ca2+ release during cardiac action potential
Electrophysiological Effects
* Direct effects
o spontaneous depolarization of atrial cardiomyocytes at high doses

Electrophysiological Effects
Overall Effect on Cardiac Function

Foxglove
Therapeutic Uses
* only orally effective inotropic agent approved in US
* also for CHF secondary to ischemic heart disease
* contraindicated in patients with Wolff-Parkinson-White syndrome
* does not stop disease progression or prolong life in CHF patients

Pharmacokinetics
* long half-life (24-36 h): once daily dosing
* high bioavailability from oral dosing
* large volume of distribution
* digoxin excreted in kidneys
* digitoxin metabolized in liver, active metabolites
* intestinal flora cause variations in toxicity

Side Effects
* extremely low therapeutic index (~2)
* most effects caused by inhibition of Na+/K+ ATPase in extracardiac tissues
* CNS: malaise, confusion, depression, vertigo, vision
* GI: anorexia, nausea, intestinal cramping, diarrhea
* Cardiac: bradycardia, arrhythmias
* anti-digoxin antibody in toxic emergencies

Serum Electrolytes affect Toxicity
* Ca2+
* hypercalcemia: increases toxicity
* K+
* digitalis competes for K+ binding site on Na+/K+ ATPase
* contraindicated with K+ depleting diuretics or patients with hypo/hyperkalemia
* hypokalemia: increased toxicity
* hyperkalemia: decrease toxicity

Example of cardiac side effects
* action potential recordings from purkinje fiber cells
* toxic doses produce oscillatory after depolorizations
* leads to ventricular tachycardia (C)

Vision Effects
* yellow-tinted vision or yellow corona-like spots

Phosphodiesterase Inhibitors
* primarily used for management of acute heart failure
* positive inotropic effects
* increase rate of myocardial relaxation
* decrease total peripheral resistance and afterload

Mechanism of Action
* inhibitor of type III cAMP phosphodiesterase
* increased [cAMP]
* increased PKA phosphorylation of Ca2+ channels in cardiac muscle
* increased cardiac contraction
* relaxes vascular smooth muscle

Therapeutic Use
* Amrinone (Inocor) and Milrinone (Primacor)
* administered IV
* milrinone is ~1o fold more potent
* T 1/2 = 2.5 h for amrinone and 30-60 min for milrinone
* effective in patients taking Beta-blockers
* does not stop disease progression or prolong life in CHF patients
* prescribed to patients non-responsive to other therapies

Side Effects

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Heart Failure



Heart Failure
By:S. Soliman MD

Definition:
* A state in which the heart cannot provide sufficient cardiac output to satisfy the metabolic needs of the body
* It is commonly termed congestive heart failure (CHF) since symptoms of increase venous pressure are often prominent
Etiology
-Inappropriate work load (volume or pressure overload)
-Restricted filling
-Myocyte loss

Causes of left ventricular failure

• Volume over load: Regurgitate valve
• Pressure overload: Systemic hypertension

Outflow obstruction
• Loss of muscles: Post MI, Chronic ischemia
Connective tissue diseases Infection, Poisons
(alcohol,cobalt,Doxorubicin)
• Restricted Filling: Pericardial diseases, Restrictive
cardiomyopathy, tachyarrhythmia

Pathophysiology
* Hemodynamic changes
* Neurohormonal changes
* Cellular changes

Hemodynamic changes
Neurohormonal changes
Cellular changes
Symptoms
Physical Signs
Framingham Criteria for Dx of Heart Failure
* Major Criteria:
o PND
o JVD
o Rales
o Cardiomegaly
o Acute Pulmonary Edema
o S3 Gallop
o Positive hepatic Jugular reflex
o ↑ venous pressure > 16 cm H2O
* Minor Criteria
LL edema,
Night cough
Dyspnea on exertion
Hepatomegaly
Pleural effusion
↓ vital capacity by 1/3 of normal
Tachycardia 120 bpm
Weight loss 4.5 kg over 5 days management

Forms of Heart Failure
* Systolic & Diastolic
* High Output Failure
o Pregnancy, anemia, thyrotoxisis, A/V fistula, Beriberi, Pagets disease
* Low Output Failure
* Acute
* Chronic
* Right vs Left sided heart failure:

Right sided heart failure :
Most common cause is left sided failure
Other causes included : Pulmonary embolisms
Other causes of pulmonary htn.
RV infarction
MS
Usually presents with: LL edema, ascites
hepatic congestion
cardiac cirrhosis (on the long
Differential diagnosis
* Pericardial diseases
* Liver diseases
* Nephrotic syndrome
* Protein losing enteropathy

Laboratory Findings

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Anaphylaxis Urticaria Angioedema



Anaphylaxis Urticaria Angioedema
By:Niraj Patel, MD, MS
Section of Allergy and Immunology
Texas Children’s Hospital & Baylor College of Medicine

Objectives
* Know the clinical presentation, diagnosis and treatment of anaphylaxis.
* Understand the pathophysiology of urticaria and angioedema
* Outline an approach for evaluation and treatment of patients with urticaria and/or angioedema

What is anaphylaxis?
* Affects > 1 organ system: skin, respiratory, cardiovascular, GI symptoms
* 100,000 episodes per year in U.S.
* 1% fatality rate: shock, larnygeal edema
* IgE vs nonIgE mechanisms

Histamine
IgE-Mediated
IgE-receptor
* Protein digestion
* Antigen processing
* Some Ag enters blood

Mast cell
APC
B cell
T cell
Non-IgE Mediated
Pathophysiology: Immune Mechanisms
Causes of Anaphylaxis
* Foods – peanuts, egg, milk, shellfish, wheat, fish, soy
* Insect stings
* Drugs – PCN, NSAIDs
* Contrast media
* Opiods

Clinical Features and Diagnosis
* Skin: Erythema, pruritis, hives, angioedema
* Respiratory: laryngeal edema, wheezing, rhinitis, itching of palate, conjunctivitis
* Cardiovascular: LOC, fainting, palpitations, sense of impending doom
* GI: N/V/D, abdominal pain
* Diagnosis

Management of Systemic Reactions
Stabilize Epinephrine, IV, airway, O2 antihistamine, steroids
Observe 3 hours (mild reaction) 6 hours (severe reaction)
Prevent Epinephrine self administration Referral to an allergist

EpiPen
* EpiPen
o Injection carried with the patient at all times.
o Self-injection to lateral thigh.
o Use EpiPen, Jr. for children < 20kgs.
Urticaria
* Urticaria = Hives
* Common condition, 15-25% at some time in their lives
* Type I hypersensitivity reaction
* Causes: foods, drugs (no identifiable cause in 50%)
Urticaria vs. Angioedema

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