Cardio - Mechanisms of Disease - Heart Failure; Ischemic Heart Disease Flashcards
Name some of the many causes of congestive heart failure.
Ischemic heart disease;
chronic hypertension;
cardiomyopathies;
infections;
toxins;
valvular disease;
prolonged arrhythmias
Systolic heart failure is associated with an S__ heart sound and _________ ventricles.
Systolic heart failure is associated with an S3 heart sound and dilated ventricles.
(3 = SYS-tolic
4 = DIAS-tolic)
Diastolic heart failure is associated with an S__ heart sound and _________ ventricles.
Diastolic heart failure is associated with an S4 heart sound and hypertrophic ventricles.
(4 = DIAS-tolic
3 = SYS-tolic)
_________ heart failure is associated with an S3 heart sound and _________ ventricles.
Systolic heart failure is associated with an S3 heart sound and dilated ventricles.
(3 = SYS-tolic
4 = DIAS-tolic)
_________ heart failure is associated with an S4 heart sound and _________ ventricles.
Diastolic heart failure is associated with an S4 heart sound and hypertrophic ventricles.
(4 = DIAS-tolic
3 = SYS-tolic)
Systolic heart failure is also known as heart failure with _________ ejection fraction (HF__EF).
Systolic heart failure is also known as heart failure with reduced ejection fraction (HFrEF).
Diastolic heart failure is also known as heart failure with _________ ejection fraction (HF__EF).
Diastolic heart failure is also known as heart failure with preserved ejection fraction (HFpEF).
Name three categories of compensatory mechanisms used by the heart to prevent complete failure:
Ventricular ___________
Neuro_________ activation
___________-__________ mechanism
Name three categories of compensatory mechanisms used by the heart to prevent complete failure:
Ventricular remodeling
Neurohormonal activation
Frank-Starling mechanism
What are the two main forms of ventricular remodeling?
- Myocardial hypertrophy
- Chamber dilatation
The hypertrophy or dilatation seen in congestive heart failure are compensatory mechanisms used to decrease what?
Ventricular wall tension
Concentric myocardial hypertrophy is to place the myocytes in _________.
Concentric myocardial hypertrophy is to place the myocytes in parallel.
Eccentric myocardial hypertrophy is to place the myocytes in ______.
Eccentric myocardial hypertrophy is to place the myocytes in series.
________ overload leads to concentric cardiac hypertrophy.
Pressure overload leads to concentric cardiac hypertrophy.
________ overload leads to eccentric cardiac hypertrophy.
Volume overload leads to eccentric cardiac hypertrophy.
Which form of cardiac hypertrophy (eccentric or concentric) sometimes occurs under normal physiologic conditions?
Eccentric
Via what two mechanisms can cardiac hypertrophy lead to myocardial ischemia?
- Increased O2 requirement
- Myocardial growth compresses the coronary arteries
Ventricular remodeling typically results in the heart taking on a more __________ shape.
Ventricular remodeling typically results in the heart taking on a more globular (spherical) shape.
The Law of LaPlace indicates that wall tension is proportional to what two internal chamber factors?
(1) radius (r)
(2) pressure (P)
(Tension = P*r /2h)
The Law of LaPlace indicates that wall tension is inversely proportional to what factor?
Wall thickness (h)
(Tension = P*r /2h)
Is left ventricular hypertrophy more associated with systolic or diastolic heart failure?
Diastolic
Is ischemic heart disease more associated with systolic or diastolic heart failure?
Systolic
Is cardiac fibrosis/amyloidosis more associated with systolic or diastolic heart failure?
Diastolic
Is hypertension more associated with systolic or diastolic heart failure?
Systolic
Which form(s) of natriuretic peptide arise(s) from the atria?
Which form(s) of natriuretic peptide arise(s) from the CNS?
ANP, BNP;
CNP
What type of nuclei are seen in hypertrophied cardiomyocytes?
Boxcar nuclei
Left-to-right shunting can increase risk of ______-sided heart failure.
Left-to-right shunting can increase risk of right-sided heart failure.
Describe the appearance of the alveolar pink edematous fluid seen in cases of left heart failure.
Describe the appearance of the hemosiderin-laden alveolar macrophages seen in cases of left heart failure.
Describe the nutmeg liver seen in cases of right heart failure.
The nutmeg liver seen in right heart failure is a result of __________ deposition around the _______ tubular focus in the liver due to passive congestion.
The nutmeg liver seen in right heart failure is a result of hemosiderin deposition around the central tubular focus in the liver due to passive congestion.
Cardiac tumors are almost always _________ (primary/secondary).
Cardiac tumors are almost always secondary (malignant metastases).
Metastases to the heart typically come from what primary malignancies?
Lymphoma;
melanoma;
breast
Primary cardiac tumors are typically benign, of which ____% are myxomas.
Primary cardiac tumors are typically benign, of which 50% are myxomas.
50% of cardiac rhabdomyomas are associated with what condition?
Tuberous sclerosis
Cardiac myxomas are typically attached to what structure?
The interatrial septum
Cardiac fibromas are typically _______al.
Cardiac fibromas are typically congenital.
Cardiac lipomas are most common in what patient population?
Obese adults
Cardiac papillary elastomas are most common in what patient population?
Older adults
Cardiac _________ are benign proliferations of blood vessels.
Cardiac hemangiomas are benign proliferations of blood vessels.
What is the most common primary cardiac malignancy?
Angiosarcoma
(then rhabdomyosarcoma, then leiomyosarcoma)
Describe the histology of myxomas.
Stellate or globular myxoma cells with abundant eosinophilic cytoplasm; placed in an abundant mucopolysaccharide ground substance
True/False.
For all intents and purposes, ischemic heart disease and coronary artery disease are the same condition.
True.
90% of cases of coronary artery disease / ischemic heart disease are caused by what?
Coronary artery atherosclerosis
Myocardial ischemia is defined as a mismatch between oxygen _______ and oxygen _______.
Myocardial ischemia is defined as a mismatch between oxygen supply and oxygen demand.
Myocardial oxygen demand is mainly dependent on what factors?
Contractility;
wall tension
A pressure-flow graph shows that flow ________s as the pressure decreases (as in cases of stenosis).
A pressure-flow graph shows that flow decreases as the pressure decreases (as in cases of stenosis).
What is the threshold of coronary artery occlusion that can lead to angina pectoris?
70% occlusion
A coronary artery 70% occlusion results in a pressure drop of ____ mmHg.
A coronary artery 90% occlusion results in a pressure drop of ____ mmHg.
A coronary artery 70% occlusion results in a pressure drop of 45 mmHg.
A coronary artery 90% occlusion results in a pressure drop of 55 mmHg.
The coronary artery oxygen supply is dependent on __________ (systolic/diastolic) pressures.
The coronary artery oxygen supply is dependent on diastolic pressures.
What equation represents the relationship between pressure and flow?
Flow = pressure / resistance
(Think Ohm’s law — Voltage = Current * Resistance — V = IR)
Name three acute coronary syndromes.
- Angina pectoris
- Sudden cardiac death
- Myocardial infarction
What are the three main types of angina pectoris?
- Stable (classical)
- Unstable (crescendo)
- Printzmetal (variant)
Stable angina typically requires ≥ ___% occlusion of coronary vessels.
Stable angina typically requires ≥ 75% occlusion of coronary vessels.
Unstable angina typically requires ≥ ___% occlusion of coronary vessels.
Unstable angina typically requires ≥ 90% occlusion of coronary vessels.
Printzmetal angina is associated with changes in which of the following?
Activity level
Heart rate
Blood pressure
None!
Coronary artery vasospasm
What type of angina typically occurs in young females, is associated with cigarette/cocaine use, occurs in the early morning hours, and is associated with migraines and Raynaud’s phenomenon?
Printzmetal
What type of clinical/laboratory results are seen in Printzmetal angina?
Transient ST-segment elevation
(and subsequently found to not have high grade coronary stenosis at coronary arteriography)
Describe the therapeutic goals in treating Printzmetal angina.
- Treat with nitroglycerin and/or calcium channel blockers (vasodilators)
- Eliminate risk factors; e.g. smoking and/or drug abuse
What are the most dangerous clinical outcomes associated with Printzmetal angina?
Myocardial infarction and life-threatening arrhythmias
(25% of untreated cases)
___ - ___ minutes of severe ischemia are necessary for irreversible necrosis of cardiac myocytes.
20 - 40 minutes of severe ischemia are necessary for irreversible necrosis of cardiac myocytes.
_________ cardiomyocytes use the most energy and will die first in cases of infarction.
Endocardial cardiomyocytes use the most energy and will die first in cases of infarction.
Describe the way myocardial infarctions spread through the heart layers.
Which is more damaging, (1) myocardial ischemia or (2) the reperfusion injury following administration of thrombolytics?
Myocardial ischemia
Cardiogenic shock is most likely after the death of ___% of cardiomyocytes.
Cardiogenic shock is most likely after the death of 40% of cardiomyocytes.
True/False.
More myocardial death leads to more serum troponin I.
(Directly proportional)
True.
Via what mechanism does exercise/stress cause angina pectoris in patients with coronary artery disease?
The stenotic vessel fails to meet the increased myocardial oxygen demand
Angina is characterized by __________ (reversible/irreversible) myocardial damage.
Angina is characterized by reversible myocardial damage.
The coronary arteries can typically supply all the needed oxygen to the myocardium until atherosclerotic plaques occlude a minimum of ___% of the vessel.
The coronary arteries can typically supply all the needed oxygen to the myocardium until atherosclerotic plaques occlude a minimum of 70% of the vessel.
An angina episode typically lasts ≤ ___ minutes.
An angina episode typically lasts ≤ 20 minutes.
Why is it valuable to know that angina episodes don’t last any longer than 20 minutes?
That is the extent to which myocardial ischemia/damage is completely reversible
(after 20 minutes, this constitutes an AMI as the damage becomes irreversible)
What is the technical term for heavy sweating (often as a result of AMI)?
Diaphoresis
Why does stable angina present with ST segment depressions?
The subendocarium is farthest from the coronary arteries, hence it is damaged by ischemic conditions first
(ST depression indicates subendocardial ischemia)
________ angina is an example of subendocardial ischemia.
Stable angina is an example of subendocardial ischemia.
True/False.
As opposed to stable angina, unstable angina represents irreversible damage to myocardial tissue.
False.
Unstable angina represents reversible damage to myocardial tissue.
What typically causes episodes of unstable angina?
Plaque rupture
(+ thrombosis and incomplete resulting vessel occlusion)
Atherosclerotic plaques usually rupture along which portion of the plaque bulge?
The plaque neck
(the junction of the plaque with normal intima)
Stable angina is characterized by ST segment _____________.
Unstable angina is characterized by ST segment _____________.
Stable angina is characterized by ST segment depression.
Unstable angina is characterized by ST segment depression.
(Both examples of subendocardial ischemia)
Unstable angina results from plaque rupture and __________ occlusion of a coronary vessel.
AMIs results from plaque rupture and __________ occlusion of a coronary vessel.
Unstable angina results from plaque rupture and incomplete occlusion of a coronary vessel.
AMIs results from plaque rupture and complete occlusion of a coronary vessel.
The S/Sy associated with an AMI ______ (are/are not) reversed by administration of nitroglycerin.
The S/Sy associated with an AMI are not reversed by administration of nitroglycerin.
In descending order of occurrence, name the three most commonly infarcted coronary arteries.
- L anterior descending a.
- R coronary a.
- L circumflex a.
Which portions of the heart are damaged in an infarction of the LADA?
The anterior wall of the left ventricle
+
the anterior portion of the interventricular septum
Which portions of the heart are damaged in an infarction of the RCA?
The posterior wall of the left ventricle
+
the posterior portion of the interventricular septum
Which portion of the heart is damaged in an infarction of the left circumflex artery?
The lateral wall of the left ventricle
True/False.
Myocardial infarctions typically spare the right ventricle and atria.
True.
The very initial phase of an AMI shows ST segment ____________.
The subsequent phases of an AMI shows ST segment ____________.
The very initial phase of an AMI shows ST segment depression.
(subendocardial)
The subsequent phases of an AMI shows ST segment elevation.
(transmural)
Describe the various cardiac markers used in diagnosing AMI.
Troponin I is typically used in clinical diagnosis of AMI because it has early onset (___ hrs), sensitive, specific (only found in cardiac myocytes), and lasts long (___ hrs).
Troponin I is typically used in clinical diagnosis of AMI because it has early onset (4 hrs), sensitive, specific (only found in cardiac myocytes), and lasts long (40 hrs).
Describe the effects of the various infarctions on myocardial tissue:
Permanent vessel occlusion
Global hypotension
Microinfarcts
In myocardial infarctions, troponin I rises after _______ hours, peaks by 24 hours, and returns to normal by 7 - 10 days.
In myocardial infarctions, troponin I rises after 2 - 4 hours, peaks by 24 hours, and returns to normal by 7 - 10 days.
In myocardial infarctions, troponin I rises after 2 - 4 hours, peaks by _____ hours, and returns to normal by 7 - 10 days.
In myocardial infarctions, troponin I rises after 2 - 4 hours, peaks by 24 hours, and returns to normal by 7 - 10 days.
In myocardial infarctions, troponin I rises after 2 - 4 hours, peaks by 24 hours, and returns to normal by _____ days.
In myocardial infarctions, troponin I rises after 2 - 4 hours, peaks by 24 hours, and returns to normal by 7 - 10 days.
In myocardial infarctions, CK-MB rises after _______ hours, peaks by 24 hours, and returns to normal by 7 - 10 days.
In myocardial infarctions, CK-MB rises after 4 - 6 hours, peaks by 24 hours, and returns to normal by 3 days.
In myocardial infarctions, CK-MB rises after 4 - 6 hours, peaks by ____ hours, and returns to normal by 3 days.
In myocardial infarctions, CK-MB rises after 4 - 6 hours, peaks by 24 hours, and returns to normal by 3 days.
In myocardial infarctions, CK-MB rises after 4 - 6 hours, peaks by 24 hours, and returns to normal by _____ days.
In myocardial infarctions, CK-MB rises after 4 - 6 hours, peaks by 24 hours, and returns to normal by 3 days.
What is CK-MB most useful for in diagnosing AMI?
Diagnosing a suspected second AMI
(troponin stays in the blood stream for a week or more; CK-MB is gone after 3 days)
What medication is given as an antiarrhythmic in patients with AMIs?
Beta blockers
Why are ACE inhibitors administered in patients with AMIs?
To reduce cardiac remodelling
(and left ventricular dilatation)
The Pathoma method of remembering the phases of histological change post-MI:
______ < 1 day > ______ < 1 week > ______ < 1 month > ______
The Pathoma method of remembering the phases of histological change post-MI:
Coagulation necrosis < 1 day > Inflammation (acute, then chronic) < 1 week > Granulation tissue < 1 month > Scarring
What is the microscopic change in heart muscle in the first four hours after an infarction?
None
What is the microscopic change in heart muscle 4 - 24 hours after an infarction?
Coagulative necrosis
What is the microscopic change in heart muscle at 1 - 3 days after an infarction?
Neutrophilic infiltrate
What is the microscopic change in heart muscle at 4 - 7 days after an infarction?
Monocyte infiltrate
What is the microscopic change in heart muscle at 1 - 3 weeks after an infarction?
Granulation tissue
+
fibroblasts, collagen, and blood vessels
What is the microscopic change in heart muscle months after an infarction?
Fibrosis
Name some of the complications associated with acute myocardial infarction.
Arrhythmias
Left ventricular failure
Cardiogenic shock
Myocardial rupture
Thrombosis
Ventricular aneurysm
Valvular incompetence
Sudden cardiac death
Describe the histology of infarcted myocardial tissue after 1 day.
Describe the histology of infarcted myocardial tissue after 3-4 days.
Describe the histology of infarcted myocardial tissue after 1 week.
Describe the histology of infarcted myocardial tissue after 2-4 weeks.
Describe the histology of infarcted myocardial tissue after months.
What gross and microscopic features are visible during the first hour of AMI (reversible stage)?
None
What gross and microscopic features are visible at ~4 hours of AMI (irreversible stage)?
None
Describe the changes in gross myocardial appearance:
0 - 4 hours — None
4 - 24 hours
1 - 10 days
2 weeks
2 months — Gray-white scar
0 - 4 hours — None
4 - 24 hours — Dark mottling
1 - 10 days — Yellow-tan infarct and softening
2 weeks — Red-gray mottling
2 months — Gray-white scar
Describe the changes in gross myocardial appearance:
0 - 4 hours
4 - 24 hours
1 - 10 days
2 weeks — Red-gray mottling
2 months — Gray-white scar
0 - 4 hours — None
4 - 24 hours — Dark mottling
1 - 10 days — Yellow-tan infarct and softening
2 weeks — Red-gray mottling
2 months — Gray-white scar
A patient is most at-risk for which complication in the first 24 hours post-MI?
Arrhythmia
When is a patient most at-risk for cardiogenic shock and heart failure post-MI?
The first 4 hours
When is a patient at most risk of developing fibrinous pericarditis following an MI?
1 - 3 days
(transmural inflammation / neutrophil infiltrate in myocardium)
A patient is at-risk for what complications 4 - 7 days post-MI?
Ruptures
(ventricular free wall, interventricular septum, papillary muscle)
(macrophage phase — destroying dead tissue)
A patient is at-risk for what complications months post-MI?
Aneurysm (and mural thrombus), Dressler’s syndrome
Occlusion of which coronary artery is most likely to lead to papillary muscle rupture?
The RCA
What form of cardiomyopathy is associated with HIV?
Systolic heart failure
(dilated cardiomyopathy)
What form of cardiomyopathy is associated with multiple myeloma?
Restrictive cardiomyopathy
(amyloid deposits)
Metastases to the heart often present as ______-sided heart failure.
Metastases to the heart often present as left-sided heart failure.
Doxorubicin-induced cardiomyopathy often presents as ______-sided heart failure.
Doxorubicin-induced cardiomyopathy often presents as left-sided heart failure.
What form of cardiomyopathy is associated with tuberculosis infection?
Constrictive cardiomyopathy
(calcified pericardium)
