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CARDIOLOGY
CARDIOMYOPATHIES
- Cardiomyopathy refers specifically to problems within the heart muscle, and these problems usually result in heart failure. 1. Dilated 2. Hypertrophic 3. Restrictive
Ischemic cardiomyopathy implies that the cause of muscle damage is coronary artery disease
Dilated
Cardiomyopathy
o Dilated cardiomyopathy implies that the muscle damage has resulted in enlargement of the heart Generally Idiopathic Impaired Systolic Function ________________________
Etiologies
- Most times – Idiopathic (50%)
- Myocarditis (in Children)
- Alcohol Abuse
- Cocaine Abuse
- Tachycardias – AFib / SVT
- Autoimmune Disease - Lupus and Rheumatoid Arthritis
- Pheochromocytoma - Excess Catecholamine release from a tumor
- Coronary Artery Disease - Ischemic Cardiomyopathy
- Deficiencies of certain vitamins and minerals - Thiamine, Calcium, Magnesium
- End-stage kidney disease
_________________________
- Most common Cardiomyopathy
- Dilated Cardiomyopathy is a condition in which the heart becomes weakened and enlarged, and it cannot pump blood efficiently
- The decreased heart function can affect the lungs, liver, and other body systems _________________________
Etiologies
- Thyroid
- Infections - HIV / Viral
- Chagas Disease, and Lyme disease
- Inherited Disorders - Muscular Dystrophy
- Chemotherapy Meds / Toxic Medications – ** Doxorubicin **
- HTN
- Pregnancy - Peripartum Cardiomyopathy
- Stress-induced Cardiomyopathy
- Trace elements, such as Lead, Arsenic, or Mercury
- Family History
_________________________
Dilated Cardiomyopathy
Physical Exam
- Crackles
- S3 Gallop
- Elevated JVD
- Cardiomegaly
ECHO
- Global Chamber Enlargement
- Mitral Regurgitation
- Tricuspid Regurgitation
- ↓↓↓↓ Ejection Fraction
- Thrombosis
EKG
• BBB
- Poor R-wave Progression
- Arrhythmias
CXR
- Global Cardiomegaly –
- “Global Heart”
- CHF
_________________________
Dilated Cardiomyopathy
Signs & Symptoms
• CHF
- Systemic Embolus
- Pulmonary Embolus
- Deadly Arrhythmias
- Sudden Death
Treatment
- Treat Underlying Disease
- ETOH Abstinence
- Thyroid Management
- Treat CHF
- Anticoagulants
- Arrhythmia Prophylaxis
- Heart Transplant
Medications
- ACE inhibitors
- Angiotensin Receptor Blockers (ARBs) Losartan Candesartan
- Beta-blockers, such as Carvedilol Metoprolol
- Diuretics, including thiazide, loop diuretics, and potassium-sparing diuretics
- Digitalis glycosides
_________________________
Restrictive
Cardiomyopathy
- A group of disorders in which the heart chambers are unable to properly fill with blood because of “stiffness in the heart”.
- Systolic Function is preserved
_________________________
Etiologies
- Infiltrative Amyloidosis Sarcoidosis
- Non-Infiltrative Scleroderma Idiopathic Myocardial Fibrosis
- Storage Disease Hemochromatosis Fabry’s Glycogen Storage
- Endomyocardial Diseases of the heart lining (endocardium) Endomyocardial Fibrosis Loeffler's Syndrome Radiation Carcinoid
Signs & Symptoms
- CHF (w/ preserved Systolic Function)
- Arrhythmias
- Elevated JVD
- + Kussmaul’s Sign
- S3, S4 Gallop
- Mitral Regurgitation
- Tricuspid Regurgitation _________________________
Restrictive
Cardiomyopathy
- The heart is of normal size or only slightly enlarged. However, it cannot relax normally during the time between heartbeats when the blood returns from the body to the heart (diastole)
_________________________
Physical Exam
- Signs of Right Heart Failure
- S/S of underlying condition
ECHO
• LVH, RVH, LAE, RAE
EKG
CXR
- Normal to Mild Enlargement
Treatment
- Endo-myocardial Biopsy to determine etiology
- Exclude Constrictive Pericarditis
- Treat underlying disease
- Control HR / manage AFib
- Supportive Care
- Heart Transplant
- Poor Prognosis
_________________________
Conduction Disorders
NARROW QRS
Regular Rhythms
- Sinus Tach – (100 – 140)
- Atrial Flutter – (150)
- SVT – (160+)
NARROW QRS
Irregular Rhythms
- Atrial Fibrillation
- Multi-focal Atrial Tach
Atrial Fibrillation
- Most common cardiac arrhythmia
- “Quivering” of the heart muscles of the atria
- Narrow QRS,
- No P-waves
- Irregular Rhythm
- Asymptomatic and not generally life- threatening
- May have palpitations, fainting, chest pain, or congestive heart failure
- Treated with medications which either slow the heart rate or revert the heart rhythm back to normal.
- Synchronized electrical cardioversion may also be used to convert AF to a normal heart rhythm. Surgical and catheter-based therapies may also be used to prevent recurrence of AF in certain individuals.
- People with AF are often given anticoagulants such as Warfarin to protect them from stroke.
A. Fib –vs. –NSR
**1. Narrow QRS
- No P’s,
- Irregular Rhythm**
Atrial Flutter
- Electrical impulses take an abnormal path through the atria, typically circulating around the tricuspid valve in the right atrium.
- The abnormal path of the impulses makes the atria contract very rapidly, typically about 250-350 beats per minute.
- These rapid contractions are slowed when they reach the AV node often with every second or third contraction reaching the ventricle.
- Regular Rhythm, but Tachycardic
- AF comes from the atria – “Supraventricular tachycardia” - (above the ventricles)
- May cause decreased vital organ perfusion
- May be transient - known as Paroxysmal Atrial Flutter.
- More often, AF lasts for days to weeks and is known as Persistent Atrial Flutter.
- With proper treatment, Atrial F is rarely life- threatening.
- Complications of Atrial Flutter – Stroke, but can be prevented with Anti-Thrombolytic - Warfarin
- Calcium channel blockers
- Beta-blockers
- Adenosine
- Radio-Ablation to restore Rhythm
Atrial Flutter
“Sawtooth Pattern”
1 st^ Degree AV Block
- P for every QRS
- PR > 0.20 sec
- Seen in Lyme Disease
- No Intervention Required
- Do Not Add Digoxin
1 st^ Degree AV Block
nd
Degree AV Block
(Mobitz II)
- Note a P with no QRS after
- Check PR Interval
- PR Interval is equal, then Mobitz II
Treatment:
- As with type I block, AV nodal agents should be avoided, and an anti-ischemic regimen should be instituted if ischemia is suspected.
- Transcutaneous pacing pads should be applied to all patients, including asymptomatic patients, as patients with Mobitz II second-degree AV block have a propensity to progress to complete heart block.
nd
Degree AV Block
(Mobitz II)
LBBB
A cardiac conduction abnormality where activation of the Left Ventricle is delayed, which results in the left ventricle contracting later than the Rght Ventricle.
Among the causes of LBBB are:
- Aortic stenosis
- Dilated cardiomyopathy
- Acute myocardial infarction
- Extensive cases of coronary artery disease
- Primary disease of the cardiac electrical conduction system
- Long standing hypertension leading to aortic root dilation and subsequent aortic regurgitation
Treatment
- Medical Care: Patients with LBBB require complete cardiac evaluation, and those with LBBB and syncope or near-syncope may require a pacemaker.
- Surgical Care: Some patients with LBBB, a markedly prolonged QRS, and congestive heart failure may benefit from a pacemaker, which provides rapid left ventricular contractions.
LBBB
RBBB
During a right bundle branch block, the right ventricle is not directly activated by impulses travelling through the right bundle branch. The left ventricle however, is still normally activated by the left bundle branch.
These impulses are then able to travel through the myocardium of the left ventricle to the right ventricle and depolarise the right ventricle this way. As conduction through myocardium is slower than conduction through the Bundle of His-Purkinje fibres the QRS complex is seen to be widened.
The QRS complex often shows an extra deflection which reflects the rapid depolarisation of the left ventricle followed by the slower depolarisation of the right ventricle. Otherwise healthy people may have a right bundle branch block and it does not appear to cause any harm
Paroxysmal Supraventricular
Tachycardia
Supraventricular tachycardia (SVT), a common clinical condition, is any tachyarrhythmia that requires Atrial and/or Atrioventricular (AV) nodal tissue for its initiation and maintenance.
Paroxysmal Supraventricular Tachycardia (PSVT) is episodic, with an abrupt onset and termination.
It is usually a narrow-complex tachycardia that has a regular, rapid rhythm
Exceptions include Atrial Fibrillation (AF) and Multifocal Atrial Tachycardia (MAT). Aberrant conduction during SVT results in a wide-complex tachycardia.
SVT occurs in persons of all age groups, and treatment can be challenging.
Manifestations of SVT are quite variable; patients may be asymptomatic or they may present with minor palpitations or more severe symptoms.
Paroxysmal Supraventricular
Tachycardia
Ventricular Tachycardia
- Wide-complex tachycardia; V tach;
- Ventricular tachycardia (VT) is a rapid heartbeat that starts in the ventricles
- Defined as HR of 100 + bpm + 3 irregular heartbeats in a row
- May develop as an early or late complication of an M.I.
- Major cause of sudden cardiac death.
May occur in pts w/
- Cardiomyopathy
- Heart failure
- Heart surgery
- Myocarditis
- Valvular heart disease
- pts w/ no cardiac disease
Can also be caused by:
- Anti-arrhythmic medications
- Changes in blood chemistry - Hypokalemia
- Changes in pH (acid-base)
- Hypoxia
Symptoms
- Chest discomfort (angina)
- Syncope
- dizziness
- Palpitations
- Shortness of breath
Note: Symptoms may start and stop suddenly. In some cases, there are no symptoms.
Signs:
- Absent pulse
- Loss of consciousness
- Normal or low blood pressure
- Rapid pulse
Ventricular Tachycardia
_________________
Treatment Treatment depends on the symptoms, and the type of heart disorder - may not need treatment.
Emergency V Tach:
- CPR
- Defibrillation / Cardioversion
- Anti-arrhythmic medications
- Lidocaine
- Procainamide - IV
- Sotalol - IV
- Amiodarone – IV
Long-term treatment may require the use of oral anti-arrhythmic medications
- Procainamide
- Amiodarone
- Sotalol
- Radiofrequency Catheter Ablation curative
- Preferred treatment for many chronic VT - Implantable Cardioverter Defibrillator (ICD).
Torsades de Pointes
Polymorphic ventricular tachycardia with a characteristic twist of the QRS
- Ventricular Tachycardia that is often due to congenital heart disease or the use of certain medications.
- "twisting of the points".
TdP can be:
- Inherited as congenital mutations of ion channels carrying the cardiac impulse/action potential
- Acquired as a result of drugs that block these cardiac ion currents.
Common causes
- Diarrhea
- Hypomagnesemia
- Hypokalemia.
Can also be the side effect of anti-arrhytmic medications such as Sotalol, Procainamide and Quinidine.
________________________
Other Causes:
- Familial long QT syndrome
- Class IA antiarrhythmics
- Class III antiarrhythmics
- Hypocalcemia
- Hypoxia
- Acidosis
- Heart failure
- Left ventricular hypertrophy
- Slow heart rate
- Female gender
- Hypothermia
- Subarachnoid hemorrhage
- Malnourishment
- Chronic alcoholics.
- Drug interactions:
- Erythromycin or Moxifloxacin, taken concomitantly Nitroimidazol
- Various medications like methadone, lithium, tricyclic antidepressants or phenothiazines may also contribute
Ventricular Fibrillation
(continued)
Conditions that can lead to VF include:
- Congenital heart disease
- Electrocution accidents or injury to the heart
- Heart attack
- Heart muscle disease, including Cardiomyopathy
- Heart surgery
- Ischemia
- Sudden cardiac death typically occurring in athletes after a trauma over the surface of the heart
Most people with VF have no history of heart disease. However, many have risk factors for cardiovascular disease, such as smoking, high blood pressure, and diabetes.
Ventricular Fibrillation
(continued)
Symptoms
A person who has a VF episode will suddenly collapse or become unconscious, because the brain and muscles have stopped receiving blood from the heart.
The following symptoms may occur within 1 hour before the collapse:
- Chest pain
- Dizziness
- Nausea
- Rapid heartbeat
- Shortness of breath
Treatment
- External defibrillator.
- Medicines may be given to control the heartbeat and heart function.
Ventricular Flutter
Tachycardia affecting the ventricles with a rate over 200 beats/min.
It is characterized on the ECG by a sinusoidal waveform without clear definition of the QRS and T waves.
It is considered transition stage between Ventricular Tachycardia and V. Fibrillation
Critically unstable arrhythmia that can result in sudden cardiac death.
Congenital Heart Diseases Congenital Heart Diseases
Atrial Septal Defect
“Hole in the Heart”
The 3 major types of Atrial Septal defect (ASD)
- Ostium secundum : The most common type of ASD accounting for 75%
- Ostium primum : The second most common type of ASD commonly associated with Mitral valve abnormalities.
- Sinus venosus : The least common of the three
Treatment
- ASD may not require treatment if there are few or no symptoms, or if the defect is small.
- Surgical closure of the defect is recommended if the defect is large, the heart is swollen, or symptoms occur.
Murmur
Congenital heart defect in which the wall that separates the upper heart chambers (atria) does not close completely
ASD is not very common.
In fetal circulation, there is normally an opening between the two atria to allow blood to bypass the lungs. This opening usually closes around the time the baby is born.
If the ASD is persistent, blood continues to flow from the left to the right atria. This is called a shunt.
If too much blood moves to the right side of the heart, pressures in the lungs build up. The shunt can be reversed so that blood flows from right to left.
Small Atrial Septal defects often cause very few problems and may be found much later in life
In advanced and severe cases with large shunts the increased pressure on the right side of the heart would result in reversal of blood flow (now from right to left). This usually results in significant shortness of breath.
When the person has no other congenital defect, symptoms may be absent, particularly in children. Symptoms may begin any time after birth through childhood.
Individuals with ASD are at an increased risk for developing a number of complications including:
- Atrial fibrillation (in adults)
- Heart failure
- Pulmonary over-circulation
- Pulmonary hypertension
- Stroke
Patent Ductus Arteriosus
Condition where the Ductus Arteriosus (the blood vessel joining the Pulmonary Artery to the Aorta) fails to close after birth, causing a left to right shunt with blood continuing to flow from the aorta to the Pulmonary Artery.
- When the Ductus Arteriosus is small, no symptoms are present.
- A Ductus Arteriosus with a moderate-to- large left-to-right shunt may be associated with a hoarse cry, cough, lower respiratory tract infections, Atelectasis, or pneumonia.
- When the defect is large, CHF with Dyspnea and poor weight gain or failure to thrive are the main presentations.
Causes
- Prematurity
- Low birth weight
- Prostaglandins
- Maternal rubella in the first trimester of pregnancy is thought to be a cause of the seasonal incidence of PDA.
- High altitude and low atmospheric oxygen tension have been associated with persistence of the PDA.
- Hypoxia
Patent Ductus Arteriosus
Physical
- Tachypnea
- Tachycardia
- Diaphoresis
- Cyanosis
- Bounding peripheral pulses
- Wide Pulse Pressure
- Clubbing
Murmur
- Systolic Thrill
- Continuous or Machinery Murmur is best heard at the upper left sternal border or left Infra-Clavicular area.
- Systolic Ejection Murmur
- Crescendo / Decrescendo
- Occasionally, auscultation of the PDA reveals numerous clicks or noises resembling shaking dice or a bag of rocks.
- An apical diastolic rumble with a large left to right shunt may be present.
Patent Ductus Arteriosus
Treatment
- General measures o Pulmonary support o Oxygen to correct hypoxemia o Sodium and fluid restriction o Correction of anemia
- Medical management consists of amelioration of CHF symptoms.
- No exercise restriction is required in the absence of pulmonary hypertension.
- Prophylaxis against infective Endocarditis is recommended.
Medication
- Medication use in PDA is based upon the clinical status of the patient. Prostaglandins are utilized to maintain the patency of the Ductus Arteriosus until surgical ligation is performed.
When surgical ligation is not indicated, prostaglandin inhibitors (e.g., NSAIDs) are used to close the Ductus Arteriosus.
- Indomethacin is currently the drug of choice for closure of the Ductus in premature infants.
Other studies have shown equal effectiveness with ibuprofen.
Patent Ductus Arteriosus
Pediatric surgery
Indications for surgical treatment include the following:
- Failure of Indomethacin treatment
- Contraindications to medical therapy (e.g., thrombocytopenia, renal insufficiency)
- Signs and symptoms of CHF
- PDA found in an older infant.
- Infants found to have an asymptomatic PDA after the neonatal period should undergo surgical ligation preferably before the age of 1 year to prevent future complications of a PDA.
- Ductal closure is indicated for cardiovascular compromise and for reduction of the risk of Infective Endocarditis
- Contraindications to surgery include pulmonary vascular obstructive disease.
- Timing of surgery is at 1-2 years or whenever the diagnosis is made in an older infant.
- In infants with CHF, failure to thrive, pulmonary hypertension, or recurrent pneumonia, the operation is more urgent (i.e., within 3-6 months).
