Cardiovascular II Flashcards by John Fixari

What are the 6 principle mechanisms of heart disease?

Failure at the pump
Flow obstruction
Shunted flow
"Leaky" flow (bad valves)
Canduction disordes
Rupture of heart/major vessel

How well did you know this?

Not at all

Perfectly

Congestive Heart Failure definition

Failure of the heart to pump an adequate amount of blood to supply the metabolic requirements of the organs

How well did you know this?

Not at all

Perfectly

Is Congestive heart failure due to pathologic conditions inside or outside of the heart?

It may be due to either

How well did you know this?

Not at all

Perfectly

What are the compensatory mechanisms of congestive heart failure?

The heart can compensate to try and keep pace for a short time via:

Activation of neurohumoral systems
Frank-Starling Mechanism
Myocardial Hypertrophy

How well did you know this?

Not at all

Perfectly

Activation of neurohumoral mechanisms

The body releases NE to increase HR and contractility

The renin-angiotensin system is activated to retain water and salt to increase circulatory volume

How well did you know this?

Not at all

Perfectly

Frank-Starling Mechanism

Increased end diastolic filling to stretch cardiac muscle fibers, which cause the fibers to contract more forcefully and increase CO
Eventually, they cannot keep up

How well did you know this?

Not at all

Perfectly

Myocardial hypertrophy

Increase in muscle fiber size, resulting in increased thickness of the ventricular wall, but without increase in the size of the lumen

How well did you know this?

Not at all

Perfectly

Why do compensatory mechanisms fail?

Due to increase oxygen requirements of the myocardium, but without increased capillary support - resulting in susceptibility to ischemia

How well did you know this?

Not at all

Perfectly

How will decompensated muscle look compared to normal?

It will have larger nuclei and not as many fibers

How well did you know this?

Not at all

Perfectly

What are some causes of left-sided heart failure? (Etiology)

Ischemic heart disease (IHD)
Hypertension
Myocarditis
Cardiomyopathy
Valvular disease

How well did you know this?

Not at all

Perfectly

What are some causes of right-sided heart failure?

Left-sided heart failure - subsequent pulmonary congestion leads to an increased arterial pressure
Pulmonary hypertension
Valve disease
Septal defects with left-to-right shunts

How well did you know this?

Not at all

Perfectly

What are some manifestations of Congestive heart failure from Left ventricular failure

Pulmonary edema and congestion, resulting in dyspnea
Chronic cough
Orthopnea (can’t breathe laying down)

How well did you know this?

Not at all

Perfectly

What are some manifestations of Congestive heart failure from Right and/or Left ventricular failure?

Cerebral hypoxia

How well did you know this?

Not at all

Perfectly

What are some manifestations of Congestive heart failure from Right ventricular failure?

Congestion of the liver (nutmeg liver) and spleen

Edema (pitting) of subcutaneous tissues, particularly in the lower extremities

How well did you know this?

Not at all

Perfectly

What are the two forms of Congenital heart disease?

Cyanotic

Noncyanotic

How well did you know this?

Not at all

Perfectly

What are some causes of Congenital heart disease?

Environmental factors
Chromosomal abnormalities
90% are unknown and likely multifactorial

How well did you know this?

Not at all

Perfectly

What are the Noncyanotic forms of congenital heart disease

Atrial Septal Defect - allows shunting between atria
Ventricular Septal Defect - allows shunting between ventricles
Patent ductus arteriosus - connects aorta and pulmonary artery, should close a few days after birth

How well did you know this?

Not at all

Perfectly

What are the cyanotic forms of congenital heart disease?

Tetralogy of Fallot

Transposition of the great arteries

How well did you know this?

Not at all

Perfectly

What are the 4 anomalies of the Tetralogy of Fallot?

1) Ventricular septal defect
2) Narrowing of right ventricular outflow
3) Overriding of the aorta over ventricular septal defect
4) Right ventricular hypertrophy

Transposition of the great arteries

The right ventricle empties into the aorta

The left ventricle empties into the pulmonary artery

Ischemic Heart Disease

Refers to a group of related disorders that are all characterized by an imbalance between myocardial blood supply and myocardial oxygen demand (ischemia)
Primarily due to atherosclerosis
Leading cause of death in the US

What is the pathogenesis of Ischemic Heart Disease?

Coronary artery atherosclerosis (>75%)
Coronary artery thrombosis
Other factors:
-Increased myocardial oxygen demand (Hypertension)
-Decreased blood volume (hypotension)
-Decreased oxygen (pneumonia)
-Decreased oxygen-carrying capacity (anemia)

What are the different types of Ischemic Heart disease?

Angina Pectoris
Myocardial infarction
Chronic Ischemic Heart Disease with Congestive Heart Failure
Sudden Cardiac death

Angina Pectoris

(Stable Angina)
“Chest Pain” of several minutes usually associated with exercise and emotional stress and relieved by rest
Caused by transient, reversible myocardial ischemia
No myocardial necrosis occurs

Unstable Angina

Increasing frequency of chest pain with minimal/no exertion Longer lasting than stable angina Often preceded more serious ischemia or MI

Acute Myocardial Infarction

Necrosis of cardiac muscle caused by ischemia Severe ischemia lasting longer than 20-40 minutes will cause irreversible myocyte injury and cell death Myocardial ischemia also contributes to arrhythmias, probably because ischemic regions cause electrical instability - may lead to ventricular fibrilation

Acute Myocardial Infarction Clinical presentation

``` Chest pain Shortness of breathe Nausea/vomiting Diaphoresis Low-grade fever ```

Acute Myocardial Infarction PAthology

``` Coagulation necrosis (few hours) Neutrophil infiltration (few days) Granulation tissue (1 week) Scar formation (weeks-months) ```

Acute Myocardial Infarction Tests

ECG | Elevated serum proteins from damages cardiac myocytes

How does an MI look in an autopsy?

MI's less than 12 hours old are not usually grossly apparent at autopsy At 12-24 hours, infarcted areas appear reddish-blue

Acute Myocardial Infarction Treatment

-Placement of stents to open coronary vessels affected by atherosclerosis -Coronary artery by-pass grafts (CABG) -"Clot-busting" drugs such as streptokinase These may result in reperfusion injury

If a patient survives an acute MI, what is commonly seen?

Scarring of the wall - but this can reduce contractibility, which can also be a problem

Acute Myocardial Infarction Complications

``` Arrhythmia and sudden death CHF/shock Mural thrombosis/embolism Mitral valve regurgitation Ventricular aneurysm Chronic Ischemic Heart disease ```

Chronic Ischemic Heart Disease with Congestive Heart Failure

Progressive heart failure due to ischemic myocardial damage Patient usually has a history of MI Arrhythmias, CHF and subsequent MI's lead to many deaths

What is the most common cause of sudden cardiac death?

Ischemic Heart Disease (80-90%)

Sudden Cardiac Death

Sudden onset of ischemic arrhythmia with or without MI | May occur in individuals with or without a history of IHD

What are the Classifications of Cardiomyopathies

Primary - disease primarily or solely confined to a heart muscle Secondary - myocardium is involved as part of a systemic order

What are the 3 functional/morphological patterns of Cardiomyopathy?

Dilated Hypertrophic Restrictive

Dilated Cardiomyopathy

Can be primary or secondary, genetic, or acquired Hereditary in 20-50% - related to alcoholism Dilation of all 4 heart chambers Histology shows variable fibrosis and myocyte hypertrophy Poor ventricular contractility

Hypertrophic Cardiomyopathy

Primary and Genetic Autosomal dominant inheritance Missense point mutation in one of several sarcomeric gene loci Stiff ventricles prevent adequate filling

Restrictive Cardiomyopathy

Wall of the ventricles becomes stiffer with impaired filling during diastole Can be idopathic or secondary to systemic conditions that affect the myocardium

What can cause Myocarditis?

Pyogenic bacteria Viruses Parasites Hypersensitivity

Myocarditis caused by Pyogenic Bacteria

Bacteria are usually from abscesses

Myocarditis caused by Viruses

Interstitial mononuclear inflammatory cells with myocyte necrosis

Myocarditis caused by Parasites

In individual myocytes or interstitium with adjacent inflammation

Myocarditis caused by sensitivity

Often to drugs, causes a perivascular inflammatory infiltrate with many eosinophils