Hemodynamics III Flashcards
What is the most common cause of Right side heart failure?
Left side heart failure
How does LHF cause RHF?
LHF causees increased pressure in pulmonary veins, capillary beds and then pulmonary arteries which increases Right heart afterload
What is the most common cause of isolated RHF?
1.Pulmonary vascular
2.Parenchymal disease
Things like Pulmonary emphysema, recurrent pulmonary thromboembolism, and interstitial lung disease
What is Cor pulmonale?
Right heart disease caused by pulmonary hypertensive diseases Things like Pulmonary emphysema, recurrent pulmonary thromboembolism, and interstitial lung disease
What are the characteristics of Acute Cor Pulmonale?
Dilation of the right heart chambers
What is the core characteristic of chronic Cor Pulmonale?
Right ventricular hypertrophy, with dilation if the workload exceeds its capacity
What do all the diseases that cause Cor Pulmonale have in common?
The cause pulmonary hypertension
What are the clinical manifestations of RHF?
!.Lower leg edema starting with the feet
- Chronic low-grade RUQ discomfort from hepatic hypertension
- Ascites (increased abdominal girth)
What are the signs of RHF?
Peripheral edema especially of the legs, hepatomegaly, ascites and JVD
What tools are helpful in diagnosing RHF
Echocardigraphy
What drugs can work to lower pulmonary blood pressure?
Sildenafil (viagra)
What is asystole?
Total lack of cardiac pumping
What is slow death from heart failure characterized by?
Progressive dyspnea due to pulmonary edema.
How does the incidence of sudden cardiac failure change with age?
Increases with age reaching its peak in the elderly
In what gender is sudden cardiac death more prevalent?
Males
What is the most common cause of sudden cardiac death?
Coronary Artery disease
2.Hypertensive heart disease
What is sudden cardiac death usually due to?
Ventricular tachyarrythmia
What is associated with Right ventricular cardiomyopathy?
Mutations in the genes for cell adhesion proteins that function in the low resistance gap junctions between myocytes
What is familial catecholeminergic polymorphic ventricular tachycrdia?
Mutation in the genes for the Ryanodine receptors
What are afterpolarizations?
tAbnormal triggered activity due to abnormal iron fluxes that interrupt repolarization
Afterdepolarizations that occur during phase 2 or 3 are called?
Early
Afterpolarization that occurs during phase 4 are called?
Delayed
What is the normal cause of Afterrepolarization during phase 2?
Increased Calcium inflow which can be due to defective calcium channels
What is the normal cause of Afterrepolarization during phase 3?
Abnormal sodium inflow due to defective sodium channels
What causes delayed after polarizations?
High intracellular levels of calcium which can be due to marked catecholamine stimulation
What do Afterdepolarizations lead to?
Lead to tachyarrhythmias
Where is reentrant tachyarrhythmia mostlikely to happen?
In an area of patchy myocardial ischemia or scarring
What causes reentry?
Injured or abnormal myocytes intiating a signal that encounters a pathway of myocytes no longer refractory. The abnormal impulse e
Which blocks cause a cessation of conduction of electrical signal from Atria to ventricles?
Trifascicular block and AV node blockade
What are some of the causes of signal blockade?
- Myocardial scarring from infarction
- Amyloidodid
- Sarcoidosis
What does sarcoidosis in the heart do?
Sarcoidosis in the heart favors the base and this fibrosing disease causes conduction block or arrhythmias especially in young African Americans
What causes prolongation of the PR interval?
Delays in getting through the AV node most commonly
What is the normal PR interval?
120-200 milliseconds (0.12 and .20 seconds)
What is first degree AV block?
PR intervals longer than 200 milliseconds but with all impulses from Atria getting through
What is the QT interval?
From the beginning of QRS to end of T wave
What is the most common cause of prolonged QT interval?
Myocardial ischemia also low potassium calcium or magnesium or a channelopathy
Where would the defect most likely be with abnormalities in leads V1-V4?
Anterior left ventricle served by the left anterior descending coronary artery.
Where would the defect most likely be with abnormalities in leads V5-V6?
Lateral left ventricle served by the Left circumflex coronary Artery
Where would the defect most likely be with abnormalities in leads II, III, and aVF?
Inferior left ventricle served by the right coronary artery
What does acute blockage of a major epicardial coronary artery present as on the EKG?
ST segment elevation
What is the ST segment?
The portion of the wave between the end of the QRS wave and the T wave
What does acute blockage of a major epicardial coronary artery also present as on the EKG?
Inverted T wave
What are the EKG features of Atrial fibrillation?
Irregular rhythm, the rate is high or normal and there are no P waves.
What is the cause of Atrial flutter?
A reentrant circuit around the tricupid valve
What are the features of Atrial flutter?
Two P waves for each QRS and yeilds a heart rate around 150 per minute
What is the cause of supraventricular tachycardia?
Reentrant pathway in the atria right near the AV node
What is a home remedy one can do that would help with supraventricular tachycardia?
Valsalva manuver, carotid sinus massage or immersion of the face in a pan of ice
What is important about Ventricular fibrillation?
It is immediately life-threatening
What is the cause of Ventricular Fibrillation?
Due to fragmentation of the wave of depolarization into numerous tiny wavelets going every which way
How would Ventricular fibrillation appear on ECG?
Chaotic pattern without discrete QRS complexes
What is the treatment for ventricular fibrillation?
Electrical defib if not available a punch to the sternum
What is the characteristic arrhythmia associated with long QT syndrome?
Torsades de Pointes
What is the cause of congenital long QT syndrome
Mutations in the gene for a subunit of the Iks potassium channel resulting in decreased outward potassium current, which impairs the repolarizing current prolonging the QT interval and allowing early afterdepolarizations
In what subset of patients is Brugada syndrome most prevalent?
Young adult Asian males
What is the cause of Brugada?
Genetic mutations in gene for cardiac sodium channel
What are the effects of the mutated sodium channels in Brugada
- Reduced duration of action potentials
- Persistently elevated ST segments
- Inverted T-Wave in leads V1-V3
- Ventricular Fibrillation
