Podcast
Questions and Answers
What is the primary purpose of antibiotic prophylaxis in dental procedures?
What is the primary purpose of antibiotic prophylaxis in dental procedures?
- To prevent transient bacteremia during dental work.
- To reduce pain during dental treatments.
- To protect prosthetic valves in high-risk patients. (correct)
- To enhance recovery from dental procedures.
Which junctions in cardiac muscle facilitate electrical coupling for synchronous contraction?
Which junctions in cardiac muscle facilitate electrical coupling for synchronous contraction?
- Desmosomes
- Adherens junctions
- Gap junctions (correct)
- Tight junctions
What characterizes the absolute refractory period in cardiac muscle contractions?
What characterizes the absolute refractory period in cardiac muscle contractions?
- New action potentials can be generated.
- No new action potential is possible. (correct)
- The muscle can respond to a very weak stimulus.
- The muscle is fully excitable.
How does sympathetic nervous system stimulation affect heart rate and contractility?
How does sympathetic nervous system stimulation affect heart rate and contractility?
In comparison to skeletal muscle, how does cardiac muscle's excitation-contraction coupling differ?
In comparison to skeletal muscle, how does cardiac muscle's excitation-contraction coupling differ?
What does the ECG identify in a 12-lead setup that a 3-lead system cannot?
What does the ECG identify in a 12-lead setup that a 3-lead system cannot?
Which structure acts as the primary pacemaker in the cardiac conduction system?
Which structure acts as the primary pacemaker in the cardiac conduction system?
How is troponin used as a diagnostic marker in myocardial infarction compared to angina?
How is troponin used as a diagnostic marker in myocardial infarction compared to angina?
What does the QT interval reflect in an electrocardiogram?
What does the QT interval reflect in an electrocardiogram?
Which abnormality is indicated by peaked T waves on an ECG?
Which abnormality is indicated by peaked T waves on an ECG?
What condition is characterized by a 'sawtooth' pattern of atrial waves on an ECG?
What condition is characterized by a 'sawtooth' pattern of atrial waves on an ECG?
What is the consequence of prolonged PR intervals in an electrocardiogram?
What is the consequence of prolonged PR intervals in an electrocardiogram?
Which part of the ECG represents ventricular depolarization?
Which part of the ECG represents ventricular depolarization?
What does the phenomenon of overdrive suppression ensure in cardiac physiology?
What does the phenomenon of overdrive suppression ensure in cardiac physiology?
What does ST segment elevation on an ECG typically indicate?
What does ST segment elevation on an ECG typically indicate?
Which condition is indicated by chaotic rhythm and the absence of QRS complexes in an ECG?
Which condition is indicated by chaotic rhythm and the absence of QRS complexes in an ECG?
What is a common symptom associated with pericarditis?
What is a common symptom associated with pericarditis?
Which condition is characterized by inflammation of the myocardium?
Which condition is characterized by inflammation of the myocardium?
Which of the following best describes the contraction pattern of cardiac muscle?
Which of the following best describes the contraction pattern of cardiac muscle?
What does cardiac tamponade refer to?
What does cardiac tamponade refer to?
Which type of cardiomyopathy is noted for weakened and stretched heart muscles?
Which type of cardiomyopathy is noted for weakened and stretched heart muscles?
What composes the cardiac conduction system?
What composes the cardiac conduction system?
Which layer of the heart wall is responsible for the contraction necessary for pumping blood?
Which layer of the heart wall is responsible for the contraction necessary for pumping blood?
Which valvular closure is associated with the S2 heart sound?
Which valvular closure is associated with the S2 heart sound?
Flashcards
Antibiotic Prophylaxis in Dental Procedures
Antibiotic Prophylaxis in Dental Procedures
Using antibiotics to prevent infective endocarditis in high-risk patients before dental procedures that can cause transient bacteremia to protect valves
Cardiac Muscle Contraction
Cardiac Muscle Contraction
Muscle contraction in the heart driven by calcium, sarcomeres & t-tubules/SR for Ca+ influx → contraction then Ca+ reuptake for relaxation
Intercalated Disks in Cardiac Muscle
Intercalated Disks in Cardiac Muscle
Gap junctions and desmosomes that electrically couple cardiac muscle cells for synchronous contraction, and provide mechanical support for a coordinated heartbeat.
Cardiac vs Skeletal Muscle Excitation-Contraction Coupling
Cardiac vs Skeletal Muscle Excitation-Contraction Coupling
Signup and view all the flashcards
Troponin Changes in Angina vs. MI
Troponin Changes in Angina vs. MI
Signup and view all the flashcards
Cardiac Conduction System
Cardiac Conduction System
Signup and view all the flashcards
Cardiac vs Neuronal Action Potentials
Cardiac vs Neuronal Action Potentials
Signup and view all the flashcards
Autonomic Effects on Cardiac Conduction
Autonomic Effects on Cardiac Conduction
Signup and view all the flashcards
P wave
P wave
Signup and view all the flashcards
PR interval
PR interval
Signup and view all the flashcards
QRS complex
QRS complex
Signup and view all the flashcards
ST segment
ST segment
Signup and view all the flashcards
Atrial fibrillation (AFib)
Atrial fibrillation (AFib)
Signup and view all the flashcards
Ventricular tachycardia (VT)
Ventricular tachycardia (VT)
Signup and view all the flashcards
ST elevation
ST elevation
Signup and view all the flashcards
Overdrive suppression
Overdrive suppression
Signup and view all the flashcards
ASD vs. VSD
ASD vs. VSD
Signup and view all the flashcards
Cardiac Muscle
Cardiac Muscle
Signup and view all the flashcards
Heart Sound S1
Heart Sound S1
Signup and view all the flashcards
Heart Sound S2
Heart Sound S2
Signup and view all the flashcards
Cardiac Tamponade
Cardiac Tamponade
Signup and view all the flashcards
Pericardial Layers
Pericardial Layers
Signup and view all the flashcards
Pericarditis
Pericarditis
Signup and view all the flashcards
Blood Flow (Deoxygenated)
Blood Flow (Deoxygenated)
Signup and view all the flashcards
Study Notes
Anatomy & Physiology of the Heart
- Apex: The pointed tip of the heart, located at the 5th intercostal space near the midclavicular line. It's formed by the left ventricle and acts as a landmark for auscultating heart sounds.
- Base: The broad, flat upper portion of the heart, located near the 2nd rib, opposite the apex. It's the entry/exit point for major blood vessels (aorta and pulmonary trunk).
- Atria: The upper chambers of the heart receiving blood.
- Right Atrium: Receives deoxygenated blood from the superior vena cava, inferior vena cava, and coronary sinus.
- Left Atrium: Receives oxygenated blood from pulmonary veins.
- Ventricles: The lower chambers of the heart pumping blood out.
- Right Ventricle: Pumps deoxygenated blood to the pulmonary arteries.
- Left Ventricle: Pumps oxygenated blood to the aorta.
- Septum: A wall dividing chambers within the heart.
- Interatrial Septum: Separates the right and left atria. The fossa ovalis is a remnant of a fetal opening.
- Interventricular Septum: Separates the right and left ventricles.
- Atrioventricular (AV) Valves: Regulate blood flow between atria and ventricles.
- Tricuspid: Between the right atrium and the right ventricle.
- Mitral (Bicuspid): Between the left atrium and the left ventricle.
- Semilunar Valves: Prevent backflow from the arteries into the ventricles.
- Pulmonary Valve: Between the right ventricle and the pulmonary trunk.
- Aortic Valve: Between the left ventricle and the aorta.
- Major Vessels:
- Aorta: The largest artery, carrying oxygenated blood from the left ventricle to the body.
- Pulmonary Trunk & Arteries: Carry deoxygenated blood from the right ventricle to the lungs.
- Pulmonary Veins: Return oxygenated blood from the lungs to the left atrium.
- Superior Vena Cava (SVC): Drains deoxygenated blood from the upper body into the right atrium.
- Inferior Vena Cava (IVC): Drains deoxygenated blood from the lower body into the right atrium.
- Coronary Sinus: Collects venous blood from the heart muscle (myocardium) and empties it into the right atrium.
Heart Wall Layers
- Endocardium: The inner lining, providing a smooth surface to prevent clots.
- Myocardium: The middle, muscular layer responsible for heart contractions.
- Epicardium (Visceral Pericardium): The outer layer, containing fat and blood vessels for protection and reducing friction.
- Parietal Pericardium (Fibrous Sac): Surrounds the heart, anchoring it and preventing overexpansion.
Cardiac Muscle
- Cardiac Muscle: Striated, branched, and interconnected by intercalated disks.
- Skeletal Muscle: Striated, long cylindrical fibers, controlled voluntarily.
- Smooth Muscle: Non-striated, spindle-shaped, found in organ walls, and involved in involuntary, slower contractions.
Heart Sounds
- S1 ("lub"): The sound of AV valves closing at the start of systole (ventricular contraction).
- S2 ("dub"): The sound of semilunar valves closing at the end of systole.
- S3 and S4: Additional sounds that can indicate potential heart problems.
Heart Defects
- Atrial Septal Defect (ASD): A hole in the interatrial septum, causing a left-to-right shunt and increased blood flow to the lungs.
- Ventricular Septal Defect (VSD): A hole in the interventricular septum leading to a left-to-right shunt and potentially more significant hemodynamic changes.
Other Important Concepts
- Cardiac Conduction System: The SA node (pacemaker), AV node, Bundle of His, bundle branches, and Purkinje fibers coordinate the heart's rhythm.
- ECG (Electrocardiogram): A recording of the electrical activity of the heart. Different waves (P, QRS, T) correspond to specific stages of the cardiac cycle.
- Antibiotic Prophylaxis: Prevention of infective endocarditis before dental procedures in high-risk patients.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
