Acute Coronary Syndromes and Heart Failure Practice Flashcards

A set of 40 practice flashcards covering Acute Coronary Syndromes (ACS), Myocardial Infarction pathophysiology, clinical manifestations, ECG changes, treatment modalities, and Heart Failure basics.

Why does cardiac muscle depend heavily on aerobic metabolism?

Cardiac muscle has high demands for ATP and its production drops dramatically when oxygen delivery decreases.

How does the oxygen extraction of cardiac muscle compare to other muscle types?

Cardiac muscle oxygen extraction is about $65\%$ compared to $35\%$ in other muscle types.

What is the maximum ceiling for oxygen extraction in cardiac muscle during compensation?

$80\%$ or $85\%$.

What characterizes the imbalance in myocardial ischemia?

The oxygen demand of the ventricles exceeds the supply in the coronary arteries.

How is angina pectoris defined?

Myocardial ischemia without cellular death.

What are three primary consequences of myocardial ischemia?

Decreased ventricular pumping, ischemic pain, and conduction disturbances.

What distinguishes stable angina from other forms of chest pain?

It lasts for a few minutes and is relieved by rest, position change, or nitroglycerin.

What criteria classify unstable angina as an Acute Coronary Syndrome?

Pain at rest, pain lasting longer than stable angina, new onset, or increased frequency/intensity of symptoms.

What range of clinical presentations does the umbrella term Acute Coronary Syndrome (ACS) describe?

From unstable angina to acute myocardial infarction (MI).

What physiological events follow the rupture or erosion of plaque in ACS?

Platelet adhesion, fibrin clot formation, and activation of thrombin.

How quickly does hypoxic injury to myocardial cells occur after infarction?

Within $10\,\text{seconds}$.

After how much time does anaerobic metabolism lead to irreversible injury and cell death in the myocardium?

$20\,\text{minutes}$.

What electrolyte alteration can result from the release of $K^+$ by myocardial cells during MI?

Hyperkalemia.

What can be caused by the release of $Ca^{2+}$ from myocardial cells during an MI?

Coronary artery vasospasm.

What are early vital sign changes during a Myocardial Infarction?

Elevated BP and HR.

What are late clinical manifestations of a Myocardial Infarction?

Decreased BP, decreased urine output, crackles in the lungs, and jugular vein distention.

Which prodromal symptoms of MI are most common in women?

Fatigue, sleep disturbances, dyspnea, indigestion, and anxiety.

How do Myocardial Infarctions commonly present in older adults?

Atypical presentations including fatigue, syncope, weakness, or altered mental status.

Which ECG changes are specifically associated with myocardial ischemia?

$T\,\text{wave}$ inversion and $ST\,\text{segment}$ depression.

Which ECG findings indicate myocardial injury or infarction?

$ST\,\text{segment}$ elevation and pathological $Q\,\text{waves}$.

What characterizes the ECG of a transmural infarction that is several weeks or months old?

Infarcted tissue is replaced by fibrous scar, significant $Q\,\text{waves}$ persist, and $T\,\text{waves}$ are often less inverted.

A blockage in the Right Coronary Artery (RCA) is typically associated with which location of infarction?

Inferior wall.

Which clinical complications are most associated with a Left Anterior Descending (LAD) artery occlusion?

Left ventricular failure, pulmonary edema, and cardiogenic shock.

Which cardiac enzyme is the first to appear following cell damage?

Myoglobin.

What is the clinical significance of CRP in the evaluation of MI?

It is a protein released during inflammation.

When is fibrinolysis preferred over PCI for STEMI management?

When transport to a facility for PCI takes longer than $120\,\text{minutes}$.

What are the primary components of early management for STEMI?

Relief of ischemic pain, assessment of hemodynamic state, reperfusion therapy, antithrombotic/anticoagulant therapy, and beta-blockers.

What is the mechanism of action for Alteplase (t-PA)?

It converts plasminogen to plasmin, which then degrades fibrin present in clots.

What are specific contraindications for the use of Alteplase?

Active internal bleeding, history of stroke, intracranial neoplasm, AV malformation/aneurysm, and severe uncontrolled hypertension.

What is the difference between Angioplasty and Atherectomy in PCI?

Angioplasty uses a balloon-tipped catheter to dilate the vessel, while Atherectomy involves the removal of plaque from the vessel.

What drug is used to coat Drug-eluting Stents?

Rapamune.

Which vessels are typically used as bypass grafts in a CABG procedure?

Internal mammary artery or great saphenous vein.

What is the most common complication following a Myocardial Infarction?

Arrhythmias.

Which arrhythmia occurs in approximately $40\%$ of clients after an acute MI?

Sinus Bradycardia.

AV Heart Blocks are most common with which type of wall MI?

Inferior wall MI (associated with the RCA).

What are the potential consequences of a ventricular aneurysm?

Acute heart failure, emboli, and ventricular tachycardia (VT).

What are the symptoms and treatment for post-MI pericarditis?

Symptoms include pain and a friction rub (left sternal border); treatment includes NSAIDs and ASA.

How is Heart Failure defined?

A progressive syndrome where the heart develops impaired filling or ejection due to structural and functional changes.

What is 'Cor pulmonale'?

An old term describing right ventricle failure caused by pulmonary disease.

Why does the healing process of an MI lead to diastolic dysfunction?

Necrotic areas are filled with scar tissue (collagen) which does not stretch.