CVD Pathophysiology Flashcards
(35 cards)
What percent of strokes are ischemic vs hemorrhagic?
85% ischemic
CHD stands for _________.
Coronary Heart Disease
CHD is a ____________ related disorder.
atherosclerosis
What is the rate-pressure product?
a measure of cardiac workload calculated by multiplying heart rate by systolic blood pressure. It reflects myocardial oxygen demand.
Why does stable angina resolve with rest?
The heart’s oxygen demand decreases when physical activity stops, reducing the strain on the heart and improving the balance between oxygen supply and demand.
Why does stable angina resolve with nitroglycerine?
It dilates blood vessels, reducing the heart’s workload by decreasing preload and afterload. This improves blood flow to the heart and balances oxygen supply with demand.
Why do cold, stress, or smoking exacerbate variant angina?
By triggering vasoconstriction of coronary arteries. This further reduces blood flow to the heart, leading to spasms and oxygen supply imbalance, which worsens angina symptoms.
Why does exercise improve Variant angina symptoms?
Vasodilation increases blood flow to the heart.
Why are the smallest branches of the coronary circulation found on the inside of the heart wall?
They supply the inner layers of the myocardium, which require a direct oxygen supply due to high metabolic activity.
When does isovolumic contraction occur during the cardiac cycle?
During early systole, right after the mitral and tricuspid valves close but before the aortic and pulmonary valves open. The ventricles contract with no volume change as pressure builds.
Which has a poorer prognosis – transmural of subendocardial?
Transmural because they involve the full thickness of the heart wall, leading to more extensive damage.
How are tissue ischemia, injury and infarct different?
Ischemia: Reduced blood flow, causing reversible oxygen deprivation.
Injury: Prolonged ischemia leading to damage, but still potentially reversible.
Infarct: Tissue death (necrosis) due to prolonged, irreversible injury from lack of blood flow.
Where does contraction begin in the heart? How does this affect cardiac output?
The sinoatrial (SA) node in the right atrium. This top-down contraction allows for effective filling of the ventricles and maximizes cardiac output by ensuring that blood is pushed efficiently from the atria to the ventricles before the ventricles contract.
What problems occur when blood remains in the atria?
Atrial Fibrillation: Increased risk of arrhythmias due to chaotic electrical activity.
Thrombus Formation: Stasis of blood can cause clot formation, increasing the risk of stroke.
Increased Pressure: Elevated pressure can lead to heart failure and pulmonary congestion.
Dilation of Atria: Over time, the atria can enlarge, leading to further complications.
What are the names of the 4 valves in the heart? Where are they located?
Tricuspid Valve: Located between the right atrium and right ventricle.
Pulmonary Valve: Located between the right ventricle and pulmonary artery.
Mitral Valve (or Bicuspid Valve): Located between the left atrium and left ventricle.
Aortic Valve: Located between the left ventricle and aorta.
What is the pericardium?
A double-walled sac that surrounds and protects the heart.
How does cardiac tamponade alter End Diastolic Volume?
The accumulation of fluid in the pericardial space compresses the heart, limiting its ability to expand fully during diastole. This decreases the volume of blood the heart can hold before contraction, leading to impaired filling and reduced cardiac output.
How do mural thrombus directly alter stroke volume?
By obstructing blood flow within the heart or the great vessels, reducing the amount of blood that can be ejected during ventricular contraction.
Where will mural thrombi travel to if originating in the left ventricle?
They can travel to the systemic circulation, potentially leading to embolisms in various locations, such as the brain (causing ischemic stroke), the limbs, or other organs.
Where will mural thrombi travel to if originating in the right ventricle?
They can travel to the pulmonary circulation, potentially causing a pulmonary embolism by lodging in the pulmonary arteries.
Blockage in which arteries is most likely to cause: Brady-arrhythmia?
right coronary artery (RCA)
Blockage in which arteries is most likely to cause: Left atrial dyskinesia?
left circumflex artery as it supplies blood to the lateral and posterior walls of the left atrium.
Blockage in which arteries is most likely to cause: Bundle branch block?
Left anterior descending artery (LAD) or the right coronary artery (RCA) is most likely to cause bundle branch block, as these arteries supply the conduction pathways, including the bundle branches.
Blockage in which arteries is most likely to cause: Left ventricular dyskinesia?
Left anterior descending artery
