Heart Disease 

Heart Failure	Ischemic Heart Disease
Myocardial Infarction	Hypertension
Cor Pulmonale	Valvular Heart Disease
Myocardial Disease	Cardiomyopathies
Congenital Heart Disease	Pericardial Disease
Tumors

Congestive Heart Failure
 This condition (CHF) is a common endpoint of a number of disease processes that affect
cardiac function.  CHF results when the left ventricle is unable to eject an adequate amount of
venous return to prevent a rise in venous pressure.
     High Output Failure: 
          Demand for increased cardiac output (obesity, thyrotoxicosis, anemia, Paget's
          disease) stresses a normally functioning heart.
     Low Output Failure: 
          A damaged heart is unable to provide adequate perfusion pressure.
     Forward Failure: Inadequate cardiac output.
     Backward Failure: 
          Inadequate pumping of venous return.

     Left Heart Failure: 
          1.   Ischemic Heart Disease (IHD)
          2.   Hypertension
          3.   Mitral/aortic valve disease
          4.   Myocardial disease
     Right Heart Failure:
          1.   Left Heart Failure
          2.   Intrinsic disease of lung (Cor Pulmonale)
          3.   Pulmonary vasculature disease
          4.   Pulmonary/Tricuspid valve disease
          5.   Congenital heart disease

     Cardiac Compensation
          1.   Sympathetic output
               Increase heart rate
               Increase contractility (inotropicity)
          2.   Myocardial hypertrophy
          3.   Ventricular/atrial dilatation
An injured heart that is still maintaining perfusion pressure is in compensated failure.  When
perfusion pressure becomes inadequate the patient is now in decompensated heart failure.

     Pathology findings:
          Left Heart Failure
               1.   Pulmonary edema
               2.   Heart failure cells
               3.   Brown induration of lungs
          Right Heart Failure
               1.   Pitting edema of lower extremities
               2.   Nutmeg liver
               3.   Pericardial, peritoneal, pleural edema
               4.   Abdominal visceral edema

Clinical Features
     Left Heart Failure
          1.   dyspnea
          2.   orthopnea
          3.   paroxysmal nocturnal dyspnea
          4.   cardiomegaly
          5.   third heart sound (S3)
          6.   muscle fatigue
          7.   pulmonary rales
          8.   mitral regurgitation
          9.   atrial fibrillation

     Right Heart Failure
          1.   Systemic venous congestion
          2.   Soft tissue edema
          3.   ascites
          4.   distended jugular veins
          5.   hepatomegaly
          6.   weight gain

     Combined heart failure
          All of the above plus cyanosis, ventricular arrythmias, ventricular fibrillation,
          sudden death.


Ischemic Heart Disease (IHD,CHD) 

Most common cause of death in the US.  Factors such as the rate and degree of coronary
     arterial narrowing, patients typically show one of the following patterns:

          1.   Angina pectoris
          2.   Acute MI
          3.   Sudden cardiac death
          4.   Chronic ischemic heart disease (CHID) with congestive heart failure

     Ischemia even under moderate work loads develops with arterial obstruction that reduces
     flow by 70-75%.

Angina Pectoris
     Intermittent chest pain caused by reversible cardiac ischemia.
     Typical Angina (Stable Angina)
          Intermittent substernal pain associated with fixed artherosclerotic obstruction. 
          Symptoms are typically induced by increased work load and subside with rest.
     Cresendo Angina (Unstable Angina)
          Cardiac pain that occurs with little or no exertion and persists longer than that of
          stable angina.  Indicative of plaque complication with reversible thrombus
          formation.
     Prinzmetal's Angina (Variant Angina)
          Vasospasm induced cardiac pain that may or may not correlate with atherosclerotic
          plaque obstruction.  Symptoms typically are not related to work load.



Myocardial Infarction (MI) 

A lesion defined as localized area of myocardial necrosis induced by local ischemia.  
               1.5 million MI's/yr
               0.5 million deaths/yr
               0.25 million die prior to receiving care

     Infarction is evident about 20-30 min after occlusion.
     Infarction begins in subendocardium.

          1.   Farthest away from epicardial flow.
          2.   Transmural wall pressure inhibits flow.

     Extension of necrosis occurs from the subdendocardium to the epicardium.  Full extension
     is over by about 3-6 hrs. post infarct.  Depending on the degree and duration of ischemia
     and site of obstruction, full thickness infarcts may develop (transmural infarction).


     Site of Obstruction:

          1.   LAD  40-50%
          2.   RCA  30-40%
          3.   LCx  15-20%

     Right Dominant:     LV post. wall supplied by RCA.
     Left Dominant: LV post. wall supplied by LCx.

     Complications:
     
          1.   No complications 10-20%
          2.   Cardiac arrythmias 75-95%
          3.   LVF 60%
          4.   Cardiogenic Shock 10%
          5.   Rupture (free wall, septum, papillary muscle) 4-8%
          6.   Thromboembolism 15-50%

     Lab Analysis

          1.   Creatine kinase (CK)
                    CK-MM     Skeletal muscle, heart
                    CK-MB     Myocardium, sk. musc.
                    CK-BB     Brain, lung, other
               Initial rise 2-3 hrs post MI
               Peak 24 hrs
               Return 72 hrs
               Lack of CK rise by 2 days after episode of chest pain rules out MI.
     
          2.   Lactate dehydrogenase (LD)
               Poor selectivity
               LD-1 

          3.   Cardiac troponin (cTnI)
               Specific for myocardium
               Same dynamics as CK-MB

Chronic Ischemic Heart Disease (CIHD)
     This condition leads to progressive left heart failure.  Patients usually have a history of
     angina or MI.  The primary finding is cardiomegaly resulting from both hypertrophy and
     dilatation.

     Clinical: Arrythmias
               MI
               Congestive heart failure

Sudden Cardiac Death
     Although potentially the result of many disease processes, in the US its main cause is
     cardiac ischemia.  This term refers to patients that die within at most 24 hrs after onset of
     symptoms.  This is the initial manifestation of over 50% of all people with ischemic
     vascular disease (300,000 deaths/yr).
     The primary cause is the sudden development of a ventricular arrythmia leading to
     ventricular fibrillation.



Hypertension 
     The response of the heart to chronic increases in afterload is primarily left ventricular
     hypertrophy.  The consequences of this response include:
          1.   Increased metabolic demand
          2.   Decreased ventricular compliance
          3.   Decreased stroke volume
          4.   Increased diffusional distance
     
Clinical: Diagnosis of heart failure with a history of hypertension has a poor prognosis
          (<50% survive 5 yrs or more).

Cor Pulmonale 

     Right heart failure as a result of primary pulmonary disease (parenchymal or vascular).
     Acute cor pulmonale:     pulmonary embolism
     Chronic cor pulmonale: 
          Causes include parenchymal disease, vascular disease, dysfunctional chest
          movement, and chronic pulmonary hypertension.



Valvular Heart Disease 
     Damage to the heart valves causes two primary problems.  The development of either
     stenosis or incompetence over stresses the myocardium and the damaged valves increase
     the risk for infection. 

     Rheumatic Fever/Heart Disease
          This condition results from a cross reactive autoimmune reaction (Ab's to
          streptolysin) to laryngeal infection with group A streptococcus (3%).  Heart
          damage can occur in the acute disease or as a consequence of chronic valve
          damage.

     Rheumatic Fever
               Jones Criteria
     Major          1.   Pancarditis
                    2.   Polyarthritis
                    3.   Erythema Marginatum
                    4.   Subcutaneous nodules
                    5.   Sydenham's Chorea

     Minor          1.   Fever
                    2.   Arthralgia
                    3.   Increased ESR
                    4.   Prior R.F.
          Diagnosis is based on manifestation of 2 major criteria or 1 major and 1 minor
          criteria.

     Rheumatic Heart Disease
          Patients with repeated episodes of R.F. or unique susceptibility develop chronic
          valve damage (aortic and mitral) that becomes manifest years to decades later. 
          With the development of valve damage the patient is at risk for developing heart
          failure, infection (infective endocarditis), arrhythmias and stroke.

Calcific Aortic Stenosis
     Primarily age related calcification of the mitral and aortic valves.  In patients with a
     congenital bicuspid aortic valve, calcification may occur earlier and aggressively.
     Clinical:      Asymptomatic
                    Systolic murmur
                    L. ventricular hypertrophy
                    Angina
                    Syncope
                    Heart failure
                    Arrhythmia

Mitral Valve Prolapse
     Although mitral valve failure often occurs in conjunction with rheumatic heart disease,
     ischemic heart disease, or congestive failure, the most common primary form (5%) is
     mitral valve prolapse.  The  floppy valve' results from proteoglycan deposition within the
     leaflets.
     Clinical: Female>Male
               Age 20-40
               Asymptomatic
               Midsystolic click
               Palpitations/Chest pain
               Infective endocarditis
               Arrhythmias/Sudden death
               Depression/Anxiety

Nonbacterial Thrombotic Endocarditis (NBTE)
     Sterile vegetational growth on aortic and mitral valves.  This condition often develops on
     normal valves in the presence of either disseminated malignancy or hypercoagulable
     condtions (Marantic Endocarditis).
     Clinical: Asymptomatic
               Embolization/Stroke
               Infective endocarditis

Infective Endocarditis
     Direct infection of the valves usually occurs as a result of:
          1.   Acute IE - Healthy valves infected by virulent organsisms (Staph. aureus)
          2.   Subacute IE - Damaged valves infected by lower virulent bacteria (Strept.)

     Infection is hematogenous and seen in a number of high risk groups:
          1.   Patients with previous heart disease and or direct valve damage.
          2.   Patients with prosthetic valves.
          3.   IV drug users.

     Acute Infective Endocarditis
          The reaction to virulent infection results in rapid and profuse vegetational growth
          with valve lysis and myocardial abscess formation.  Embolization of the
          vegetations leads to brain, kidney, and myocardial infarcts and secondary infection.
          Clinical: High fever/chills
                    Septicemia
                    Murmurs
                    Valve incompetence
                    Heart failure

     Subacute Infective Endocarditis
          Clinical: Similiar to acute form but less threatening.



Myocarditis 
     Inflammation of the myocardium due to infection.  In most cases infection is viral.
     Clinical: Asymptomatic
               Arrhythmias
               Heart failure



Cardiomyopathies 
     Primary idiopathic disease of the myocardium.

     Dilated Cardiomyopathy
          Majority of all cases are idiopathic some have been associated with a history of
          viral disease, drugs, and alcohol abuse.  The heart becomes dilated, hypertrophic,
          and unable to sustain efficient cardiac emptying.
          Clinical: Ejection fraction < 25%
                    Normal (50-65%)
                    Congestive failure
                    Arrhythmias

     Hypertrophic Cardiomyopathy
          Some cases have been linked as a A.D. inheritance characteristic with respect to a
          mutation encoding for the product B-myosin.  Patients have a primarily problem of
          excessive hypertrophy of the left ventricle and interventricular septum (asymmetric
          hypertrophy) that interfers with diastolic filling.
          Clinical: Asymptomatic
                    Systolic ejection murmur
                    Exertional dyspnea
                    Heart failure
                    Arrhythmias
                    Infective endocarditis

     Restrictive Cardiomyopathy
          This disease is characterized by a decrease in diastolic filling due to a decrease in
          ventricular compliance.
          Clinical: Similar to hypertrophic cardiomyopathy without ejection murmur.



Congenital Heart Disease 
     This is a category of disease that affects about 8/1000 live births.  The cause is unknown in
     90% but these disorders are associated with genetic lesions (trisomy 13,21) and
     environmental factors (rubella infection).
     This category represents lesions that ultimately manifest as:
          1.   Left-to-Right shunts
          2.   Right-to-Left shunts
          3.   Obstructions

Left-to-Right Shunts
     This is the most common form of congenital heart defect.  They all represent abnormal
     connections between the left and right heart.  There is great variety in severity of defect,
     thus a widely variable clinical course. 
     As a group, these defects do not produce cyanosis during the initial period.  With time and
     the development of pulmonary hypertension, shunt reversal will lead to the late onset of
     cyanosis (tardive cyanosis).
     
     Atrial Septal Defect (ASD)
          Abnormal development of the interatrial septum leads to patency of the foramen
          ovale.  The failure of closure leads to blood flow from the left atria to the right
          atria (shunt).
          Clinical:      Asymptomatic in early life
                         Pulmonary hypertension
                         Shunt reversal
                         Cyanosis
                         Heart failure

     Ventricular Septal Defect (VSD)
          This is the most common form of congenital heart defect.  Connection of the right
          and left ventricle produces a shunt.
          Clinical: Small defects may be asymptomatic
                    Right ventricular hypertrophy/dilatation
                    Pulmonary arterial hypertrophy/dilatation
                    Pulmonary hypertension
                    Shunt reversal/Cyanosis
                    Heart failure
                    Infective endocarditis

     Patent Ductus Arteriosus (PDA)
          The ductus arteriosus normally closes within a couple of days of birth with
          permanent closure taking about a couple of months.  If the ductus remains patent
          (low O2, high PGE2, or other problem), a left to right shunt is present.
          Clinical: 
               Volume overload L. atria/ventricle
               L. ventricle/atrial hypertrophy/dilatation
               Pulmonary hypertension
               Shunt reversal
               Cyanosis
               Heart Failure
               Infective endocarditis

Right-to-Left Shunts (Cyanotic Defects)
     The presence of a right-to-left shunt at birth predisposes to the immediate development of
     cyanosis.

     Tetralogy of Fallot
          The most common form of cyanotic congenital heart disease.  This defect is
          composed of:
               1.   VSD
               2.   Dextraposed aorta
               3.   Pulmonary arterial stenosis
               4.   Right ventricular hypertrophy
          The shunt pattern is determined by the degree of pulmonary arterial stenosis.
          Clinical: Early severe cyanosis to none.
                    Progressive cyanosis
                    Lack of pulmonary hypertension
                    Infective endocarditis
                    Systemic/brain emboli

     Transposition of the Great Arteries
          In this condition, the aorta originates in the right ventricle and the pulmonary artery
          originates in the left ventricle.  This pattern of circulation is incompatible with
          extra-uterine life.  Survival is dependent on the presence of a VSD, ASD, or PDA.

Obstructive Congenital Heart Disease
     Coarctation of the Aorta
          Developmental aortic narrowing is found both as a solitary lesion (50%) and in
          conjunction with other cardiac anomalies.  The two forms of coarctation (preductal
          and postductal) are characterized by the position of aortic narrowing and
          distribution with respect to patient age.

          Preductal Coarctation (Infantile form)
               Narrowing occurs in the area of the aorta between the origin of the
               subclavian artery and the entry of the ductus arteriosus.  Narrowing is
               typically severe with aortic output provided by a patent ductus arteriosus.
               Clinical: L. heart failure
                         Lower extremitiy cyanosis
                         Weak femoral pulse
                         R. heart hypertrophy/dilatation
                         Fatal without surgery

          Postductal Coarctation (Adult form)
               Aortic narrowing occurs just distal to the entry of the ductus arteriosus.  The
               aorta proximal to the coarctation is dilated with collateral flow (intercostal,
               phrenic, and epigastric arteries) bypassing the constriction.
               Clinical: Upper extremity hypertension
                         Lower extremity hypotension
                         Left ventricular hypertrophy
                         Lower extremity intermittent claudication



Pericardial Disease 
     Pericarditis
          Inflammation is seen in infections (primarily viral), cardiac disease (MI), and
          systemic disease (SLE, SS, RA, Uremia), and mediastinal malignancy.
          Clinical: Chest pain
                    Friction rub
                    Cardiac tamponade
     
          Hemopericardium
               Hemorrhage of undiluted blood into the pericardium. Caused by rupture of
               aortic aneurysms or ventricle in MI and trauma.



Cardiac Tumors 
     The most prevalent form of cancer of the heart is metastatic (10% of all disseminated
     cancer).  The most common primary sites include lung, breast, melanoma (skin), and
     hematopoietic tissue.
     
     Myxoma:   Benign primary tumor of heart.  Typically grows in the l. atria and can
               cause problems of embolization and "ball-valve" restriction of mitral valve.