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CV-BC practice questions

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Question 1Cardiovascular Assessment and Diagnostic Evaluation

On a standard 12-lead ECG, a normal PR interval measures between:

  1. 0.12 and 0.20 seconds Correct answer.
  2. 0.20 and 0.40 seconds
  3. 0.30 and 0.45 seconds
  4. 0.06 and 0.10 seconds

Explanation

The PR interval spans the onset of atrial depolarization to the onset of ventricular depolarization and normally occupies 3 to 5 small boxes, or 0.12 to 0.20 seconds. Values above 0.20 seconds define first-degree AV block.

Question 2Cardiovascular Assessment and Diagnostic Evaluation

The first heart sound (S1) is produced primarily by:

  1. Atrial contraction
  2. Closure of the atrioventricular valves Correct answer.
  3. Closure of the semilunar valves
  4. Rapid ventricular filling

Explanation

S1 occurs at the onset of systole when the mitral and tricuspid valves close as ventricular pressure exceeds atrial pressure. It is best heard at the apex and marks the start of ventricular systole.

Question 3Cardiovascular Assessment and Diagnostic Evaluation

An S3 gallop heard in an adult most commonly suggests:

  1. Ventricular volume overload or heart failure Correct answer.
  2. Pericardial constriction
  3. Aortic stenosis
  4. Normal myocardial aging

Explanation

An S3 is a low-pitched early diastolic sound produced by rapid filling of a dilated, compliant ventricle, so in adults it suggests volume overload or heart failure. It can be a normal finding in children and young athletes.

Question 4Cardiovascular Assessment and Diagnostic Evaluation

A fourth heart sound (S4) is best described as:

  1. A mid-systolic click
  2. A high-pitched sound occurring right after S2
  3. A diastolic rumble at the apex
  4. A late diastolic sound from atrial contraction Correct answer.

Explanation

S4 is generated in late diastole when the atria contract into a ventricle with reduced compliance, and it is heard just before S1. It is a low-pitched sound best appreciated at the apex with the bell.

Question 5Cardiovascular Assessment and Diagnostic Evaluation

Jugular venous pressure is conventionally estimated by measuring the vertical height of the venous column above:

  1. The cricoid cartilage
  2. The xiphoid process
  3. The sternal angle Correct answer.
  4. The sternal notch

Explanation

The sternal angle is used as the zero reference because it lies roughly 5 cm above the right atrium. A venous height of up to 3 to 4 cm above the sternal angle is normal, and 5 cm is added to convert the measurement to right atrial pressure.

Question 6Cardiovascular Assessment and Diagnostic Evaluation

Conventional (non-high-sensitivity) cardiac troponin levels in acute myocardial infarction typically begin to rise within:

  1. 48 to 72 hours of symptom onset
  2. 3 to 6 hours of symptom onset Correct answer.
  3. 30 minutes of symptom onset
  4. 12 to 24 hours of symptom onset

Explanation

Conventional troponin assays typically become abnormal 3 to 6 hours after myocardial injury begins, peak around 12 to 24 hours, and remain elevated for 7 to 10 days. This delayed rise is why serial sampling was traditionally required.

Question 7Cardiovascular Assessment and Diagnostic Evaluation

B-type natriuretic peptide (BNP) is released primarily from:

  1. Ventricular myocytes in response to wall stretch Correct answer.
  2. The carotid sinus in response to hypertension
  3. The atrial appendages in response to tachycardia
  4. The renal juxtaglomerular apparatus in response to hypoperfusion

Explanation

BNP is synthesized and released by ventricular myocytes when they are stretched by pressure or volume overload. It promotes natriuresis and vasodilation and is used to help distinguish heart failure from other causes of dyspnea.

Question 8Cardiovascular Assessment and Diagnostic Evaluation

When blood pressure is measured by auscultation in an adult, the diastolic pressure corresponds to:

  1. The second Korotkoff sound
  2. The first Korotkoff sound
  3. The fourth Korotkoff sound in all adults
  4. The fifth Korotkoff sound Correct answer.

Explanation

In adults, the fifth Korotkoff phase, when sounds disappear, is recorded as the diastolic pressure. The first phase marks systolic pressure, and phase IV is used mainly when sounds persist to zero, as in children.

Question 9Cardiovascular Assessment and Diagnostic Evaluation

Paradoxical splitting of the second heart sound is most characteristic of:

  1. Mitral stenosis
  2. Left bundle branch block Correct answer.
  3. Atrial septal defect
  4. Right bundle branch block

Explanation

In left bundle branch block, delayed aortic valve closure causes P2 to precede A2, so splitting occurs during expiration and narrows during inspiration, reversing the normal pattern. Right bundle branch block and atrial septal defect instead cause widened or fixed splitting.

Question 10Cardiovascular Assessment and Diagnostic Evaluation

A widely split second heart sound that does not vary with respiration is most consistent with:

  1. Hypertrophic cardiomyopathy
  2. Pulmonary stenosis
  3. Aortic stenosis
  4. Atrial septal defect Correct answer.

Explanation

In atrial septal defect, right ventricular volume overload equalizes the effect of inspiration and expiration on right-sided filling, producing fixed splitting of S2. Pulmonary stenosis instead causes wide splitting that varies normally with respiration.

Question 11Cardiovascular Assessment and Diagnostic Evaluation

The murmur of aortic stenosis is best characterized as:

  1. A crescendo-decrescendo systolic murmur to the carotids Correct answer.
  2. A mid-diastolic rumble with an opening snap
  3. A continuous machinery murmur below the clavicle
  4. A holosystolic murmur radiating to the axilla

Explanation

Aortic stenosis produces an ejection systolic murmur that crescendos and decrescendos, peaks in mid-systole, and radiates to the carotids. It is often accompanied by a diminished or absent A2.

Question 12Cardiovascular Assessment and Diagnostic Evaluation

A holosystolic murmur heard at the apex and radiating to the axilla is most consistent with:

  1. Tricuspid stenosis
  2. Aortic regurgitation
  3. Mitral regurgitation Correct answer.
  4. Ventricular septal defect

Explanation

Mitral regurgitation produces a holosystolic murmur at the apex that radiates to the axilla because the regurgitant jet is directed posteriorly. It is often accompanied by a third heart sound from volume overload.

Question 13Cardiovascular Assessment and Diagnostic Evaluation

Which maneuver most reliably increases the murmur of hypertrophic cardiomyopathy?

  1. Squatting
  2. Isometric handgrip
  3. Passive leg elevation
  4. Valsalva strain Correct answer.

Explanation

The dynamic left ventricular outflow tract obstruction of hypertrophic cardiomyopathy worsens when preload falls, so the murmur intensifies with the Valsalva strain and with standing. Maneuvers that raise preload or afterload, such as squatting and handgrip, soften the murmur.

Question 14Cardiovascular Assessment and Diagnostic Evaluation

Pulsus paradoxus is defined as an inspiratory fall in systolic blood pressure of more than:

  1. 10 mm Hg Correct answer.
  2. 20 mm Hg
  3. 30 mm Hg
  4. 5 mm Hg

Explanation

A respiratory decline in systolic pressure exceeding 10 mm Hg is considered pulsus paradoxus and is classically seen in cardiac tamponade. It can also occur in severe obstructive lung disease and constrictive pericarditis.

Question 15Cardiovascular Assessment and Diagnostic Evaluation

Electrical alternans on an ECG is most strongly associated with:

  1. Acute myocardial infarction
  2. Left ventricular hypertrophy
  3. Large pericardial effusion Correct answer.
  4. Hyperkalemia

Explanation

Electrical alternans is a beat-to-beat variation in QRS amplitude caused by the heart swinging within a large pericardial effusion. It is often seen together with low voltage and sinus tachycardia in tamponade.

Question 16Cardiovascular Assessment and Diagnostic Evaluation

A 24- to 48-hour ambulatory ECG (Holter) monitor is most appropriate to evaluate:

  1. Left ventricular ejection fraction
  2. Structural valve disease
  3. Exercise-induced ST-segment changes
  4. Intermittent palpitations or syncope Correct answer.

Explanation

A Holter monitor continuously records the rhythm over 24 to 48 hours and is best suited to capturing transient arrhythmias that cause intermittent palpitations or syncope. Exercise-induced ischemia is evaluated with stress testing, and structural disease with echocardiography.

Question 17Cardiovascular Assessment and Diagnostic Evaluation

Which finding is an absolute contraindication to exercise treadmill stress testing?

  1. Mild aortic stenosis
  2. Stable angina
  3. Controlled hypertension
  4. Acute myocardial infarction within the past 2 days Correct answer.

Explanation

Recent acute myocardial infarction, unstable angina, uncontrolled arrhythmias, and severe symptomatic aortic stenosis are recognized absolute contraindications to exercise stress testing. Stable angina is a common indication for the test rather than a contraindication.

Question 18Cardiovascular Assessment and Diagnostic Evaluation

Which echocardiographic measurement is used to calculate left ventricular ejection fraction?

  1. Biplane end-diastolic and end-systolic volumes Correct answer.
  2. Transmitral E-wave velocity
  3. Tissue Doppler e' velocity
  4. Pulmonary artery acceleration time

Explanation

Ejection fraction equals end-diastolic volume minus end-systolic volume, divided by end-diastolic volume, and the biplane Simpson method is the standard echocardiographic approach. E-wave and tissue Doppler velocities assess diastolic function rather than systolic function.

Question 19Cardiovascular Assessment and Diagnostic Evaluation

A coronary artery calcium score of zero is most useful for:

  1. Excluding unstable angina in the emergency department
  2. Determining the need for dual antiplatelet therapy
  3. Measuring the severity of valvular calcification
  4. Confirming a low likelihood of obstructive disease Correct answer.

Explanation

In a stable patient with intermediate risk, a calcium score of zero has a high negative predictive value and makes obstructive coronary disease very unlikely. It is not used to rule out acute coronary syndrome, guide antiplatelet therapy, or grade valve calcification.

Question 20Cardiovascular Assessment and Diagnostic Evaluation

Late gadolinium enhancement on cardiac MRI is most useful for:

  1. Detecting coronary artery stenosis
  2. Identifying myocardial scar or fibrosis Correct answer.
  3. Measuring pulmonary capillary wedge pressure
  4. Quantifying aortic valve area

Explanation

Late gadolinium enhancement demonstrates areas of replacement fibrosis or scar, such as prior infarction, myocarditis, hypertrophic cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy. It does not directly measure stenosis, filling pressures, or valve area.

Question 21Cardiovascular Assessment and Diagnostic Evaluation

A fractional flow reserve of 0.78 across a coronary stenosis indicates:

  1. A normal coronary artery
  2. A lesion likely to benefit from revascularization Correct answer.
  3. A measurement that should be repeated after nitroglycerin
  4. An ostial left main lesion

Explanation

Fractional flow reserve compares distal coronary pressure with aortic pressure during maximal hyperemia, and a value of 0.80 or less identifies a hemodynamically significant stenosis. Such lesions have been shown to benefit from revascularization in appropriate clinical settings.

Question 22Cardiovascular Assessment and Diagnostic Evaluation

Deep, symmetric T-wave inversions in leads V2 and V3 in a patient whose chest pain has resolved, with no Q waves, most suggest:

  1. Left ventricular aneurysm
  2. Acute pericarditis
  3. Early repolarization
  4. Critical proximal LAD stenosis Correct answer.

Explanation

This pattern is characteristic of Wellens syndrome, which reflects critical stenosis of the proximal left anterior descending artery. Patients are at high risk for extensive anterior infarction and warrant urgent angiography even though they may be pain-free at presentation.

Question 23Cardiovascular Assessment and Diagnostic Evaluation

Aortic valve area by the continuity equation is calculated as:

  1. Peak aortic velocity divided by LVOT velocity
  2. LVOT stroke volume divided by aortic VTI Correct answer.
  3. Aortic valve area multiplied by the mean gradient
  4. LVOT diameter × LVOT velocity

Explanation

The continuity principle states that flow through the left ventricular outflow tract equals flow through the aortic valve, so valve area is the LVOT stroke volume divided by the aortic valve time-velocity integral. The ratio of LVOT to aortic velocity integrals gives the dimensionless index.

Question 24Cardiovascular Assessment and Diagnostic Evaluation

Prominent J-point elevation with a convex hump at the end of the QRS complex in a hypothermic patient is called:

  1. Delta wave
  2. Brugada pattern
  3. Osborn wave Correct answer.
  4. Epsilon wave

Explanation

The Osborn wave, or J wave, is a positive deflection at the junction of the QRS and ST segment seen in moderate to severe hypothermia, most prominently in the inferior and lateral leads. Its amplitude generally correlates with the degree of hypothermia.

Question 25Cardiovascular Assessment and Diagnostic Evaluation

A tilt-table test is most useful to confirm:

  1. Aortic dissection
  2. Vasovagal (neurocardiogenic) syncope Correct answer.
  3. Silent myocardial ischemia
  4. Mitral valve prolapse

Explanation

Head-up tilt testing reproduces the vasovagal reflex under controlled conditions, provoking hypotension and bradycardia in susceptible patients. It is used mainly when the history suggests neurally mediated syncope and the diagnosis remains uncertain.

Question 26Cardiovascular Assessment and Diagnostic Evaluation

On a standard ECG recorded at a paper speed of 25 mm/s, one small box along the horizontal axis represents how much time?

  1. 0.20 second
  2. 0.50 second
  3. 0.10 second
  4. 0.04 second Correct answer.

Explanation

At the standard paper speed of 25 mm/s, each 1 mm small box corresponds to 0.04 second, and each 5 mm large box corresponds to 0.20 second. This calibration underlies all rate and interval calculations on a standard tracing.

Question 27Cardiovascular Assessment and Diagnostic Evaluation

An audible third heart sound (S3) in an older adult most often indicates which of the following?

  1. Normal age-related change in the valves
  2. Elevated left ventricular filling pressures Correct answer.
  3. A stiff, noncompliant left ventricle
  4. Thickening of the pericardium

Explanation

An S3 is generated by rapid early-diastolic filling of a ventricle that is volume overloaded or failing, so in adults it suggests elevated filling pressures and reduced compliance. A stiff, noncompliant ventricle instead produces a fourth heart sound (S4) during late diastolic filling.

Question 28Cardiovascular Assessment and Diagnostic Evaluation

A blood pressure cuff that is too small for the patient's arm will most likely produce which result?

  1. No measurable change in the reading
  2. A falsely low systolic pressure
  3. A widened pulse pressure only
  4. A falsely elevated pressure reading Correct answer.

Explanation

An undersized cuff requires higher cuff pressure to compress the brachial artery, so both systolic and diastolic values are overestimated. The cuff bladder should encircle roughly 80% of the arm circumference for an accurate reading.

Question 29Cardiovascular Assessment and Diagnostic Evaluation

A cardiothoracic ratio greater than 0.5 on a posteroanterior chest radiograph is generally interpreted as which of the following?

  1. A normal finding in older adults
  2. Cardiomegaly Correct answer.
  3. Pericardial effusion until proven otherwise
  4. Isolated left atrial enlargement

Explanation

A cardiac silhouette wider than half the internal thoracic diameter on a posteroanterior film suggests cardiac enlargement. The ratio is unreliable on anteroposterior films or portable studies because magnification exaggerates heart size.

Question 30Cardiovascular Assessment and Diagnostic Evaluation

ST-segment elevation in leads II, III, and aVF localizes acute myocardial injury to which region of the left ventricle?

  1. Inferior wall Correct answer.
  2. Lateral wall
  3. Anterior wall
  4. Posterior wall

Explanation

Leads II, III, and aVF face the inferior surface of the left ventricle, so elevation there marks an inferior injury pattern, usually from right coronary or circumflex occlusion. Reciprocal ST depression in I and aVL commonly accompanies it.

Question 31Cardiovascular Assessment and Diagnostic Evaluation

Transesophageal echocardiography is preferred over the transthoracic approach when the main diagnostic question concerns which structure?

  1. Small mitral valve vegetations Correct answer.
  2. Aortic root size on a screening study
  3. A large pericardial effusion
  4. Global left ventricular systolic function

Explanation

The transesophageal probe sits immediately behind the left atrium and uses a higher-frequency transducer, giving superior spatial resolution for small structures such as valve vegetations and left atrial appendage thrombi. Transthoracic imaging remains the initial test for global function and effusion because it is noninvasive.

Question 32Cardiovascular Assessment and Diagnostic Evaluation

Which marker is most useful for identifying reinfarction several days after an initial myocardial infarction?

  1. Myoglobin
  2. CK-MB Correct answer.
  3. High-sensitivity troponin I
  4. Lactate dehydrogenase

Explanation

CK-MB returns to baseline within roughly 48 to 72 hours, so a new elevation after that window signals a new ischemic event. Troponins remain elevated for up to two weeks and therefore cannot reliably distinguish reinfarction from the original injury.

Question 33Cardiovascular Assessment and Diagnostic Evaluation

A pericardial friction rub is best auscultated with the patient in which position?

  1. Supine during a deep held inspiration
  2. Left lateral decubitus after exercise
  3. Standing immediately after a Valsalva maneuver
  4. Leaning forward at end-expiration Correct answer.

Explanation

The friction rub is loudest at the left lower sternal border with the diaphragm when the patient leans forward and holds expiration, because the heart then lies closer to the chest wall. The rub is a superficial, scratchy, often triphasic sound.

Question 34Cardiovascular Assessment and Diagnostic Evaluation

On myocardial perfusion imaging, a defect that appears during stress but is absent on the resting images indicates which of the following?

  1. Reversible ischemia Correct answer.
  2. Completed myocardial infarction
  3. Breast attenuation artifact
  4. Normal myocardial uptake

Explanation

A defect present with stress but normal at rest represents myocardium that is viable but underperfused when demand rises, that is, reversible ischemia. A defect present on both sets of images indicates scar from prior infarction.

Question 35Cardiovascular Assessment and Diagnostic Evaluation

On 24-hour ambulatory blood pressure monitoring, which average value is commonly used as the threshold for hypertension?

  1. 125/75 mm Hg
  2. 145/95 mm Hg
  3. 120/70 mm Hg
  4. 130/80 mm Hg Correct answer.

Explanation

Current guidelines define hypertension on ambulatory monitoring as a 24-hour average of at least 130/80 mm Hg, with daytime and nighttime thresholds set somewhat differently. Ambulatory thresholds are lower than office values because office measurement commonly overestimates pressure.

Question 36Cardiovascular Assessment and Diagnostic Evaluation

Marked prolongation of the QT interval on the ECG places the patient at greatest risk for which arrhythmia?

  1. Mobitz type I second-degree block
  2. Torsades de pointes Correct answer.
  3. Junctional escape rhythm
  4. Atrial flutter with variable block

Explanation

A prolonged QT interval predisposes to early afterdepolarizations and polymorphic ventricular tachycardia of the torsades de pointes type. Electrolyte abnormalities and QT-prolonging drugs are common precipitants.

Question 37Cardiovascular Assessment and Diagnostic Evaluation

Tricuspid annular plane systolic excursion (TAPSE) measured on echocardiography provides an estimate of which of the following?

  1. Right ventricular systolic function Correct answer.
  2. Left atrial filling pressure
  3. Mitral annular calcification
  4. Aortic valve area

Explanation

TAPSE measures longitudinal displacement of the tricuspid annulus during systole, which tracks right ventricular systolic performance. A value below about 17 mm suggests right ventricular systolic dysfunction.

Question 38Cardiovascular Assessment and Diagnostic Evaluation

A patient with syncope has coved ST-segment elevation of at least 2 mm followed by an inverted T wave in leads V1 and V2. This pattern is most consistent with which of the following?

  1. Acute pericarditis
  2. Benign early repolarization
  3. Brugada type 1 pattern Correct answer.
  4. Left ventricular hypertrophy

Explanation

The type 1 Brugada pattern consists of a coved ST elevation of 2 mm or more with a negative T wave in the right precordial leads and is associated with polymorphic ventricular tachycardia and sudden death. Recognition matters because the pattern can be dynamic and is distinct from ischemic injury.

Question 39Cardiovascular Assessment and Diagnostic Evaluation

Which test is most useful for distinguishing truly severe aortic stenosis from pseudosevere stenosis in a patient with a low ejection fraction and a low transvalvular gradient?

  1. Noncontrast cardiac CT for calcium scoring
  2. Dobutamine stress echocardiography Correct answer.
  3. 24-hour ambulatory ECG monitoring
  4. Coronary angiography

Explanation

Dobutamine increases transvalvular flow; in true severe stenosis the velocity rises above 4 m/s while the valve area stays below 1.0 cm², whereas in pseudosevere stenosis the area increases with flow. The test also reveals contractile reserve, which has prognostic value.

Question 40Cardiovascular Assessment and Diagnostic Evaluation

Cardiac output calculated by the Fick principle requires measurement of the arteriovenous oxygen content difference plus which additional variable?

  1. Oxygen consumption Correct answer.
  2. Left ventricular end-diastolic volume
  3. Pulmonary capillary wedge pressure
  4. Systemic vascular resistance

Explanation

The Fick principle states that cardiac output equals oxygen consumption divided by the arteriovenous oxygen content difference. Without a measured or assumed oxygen consumption, the equation cannot be solved.

Question 41Cardiac Disorders and Clinical Management

Cardiac output is calculated by multiplying heart rate by which variable?

  1. Stroke volume Correct answer.
  2. Systemic vascular resistance
  3. Ejection fraction
  4. Mean arterial pressure

Explanation

Cardiac output is the product of heart rate and stroke volume, the volume ejected by one ventricle per beat. Ejection fraction is a ratio (stroke volume divided by end-diastolic volume), not a multiplier in the output equation. Systemic vascular resistance and mean arterial pressure describe pressure and afterload rather than flow generation.

Question 42Cardiac Disorders and Clinical Management

Closure of the mitral and tricuspid valves produces which heart sound?

  1. S3
  2. S1 Correct answer.
  3. S2
  4. S4

Explanation

S1 occurs at the onset of ventricular systole when the mitral and tricuspid (atrioventricular) valves close. S2 results from closure of the aortic and pulmonic semilunar valves at end-systole. S3 and S4 are diastolic filling sounds.

Question 43Cardiac Disorders and Clinical Management

What is the typical normal left ventricular ejection fraction in a healthy adult?

  1. 10% to 25%
  2. 55% to 70% Correct answer.
  3. 25% to 40%
  4. 80% to 95%

Explanation

A normal adult left ventricular ejection fraction is conventionally reported as approximately 55% to 70%. Values between 40% and 55% fall in the mildly reduced range, and below 40% defines reduced ejection fraction. Values approaching 80% or more are not typical at rest and suggest hyperdynamic states or measurement error.

Question 44Cardiac Disorders and Clinical Management

Occlusion of which coronary artery most commonly produces an inferior myocardial infarction?

  1. Right coronary artery Correct answer.
  2. Left main coronary artery
  3. Left circumflex artery
  4. Left anterior descending artery

Explanation

The right coronary artery supplies the inferior wall in most individuals, so its occlusion is the usual cause of an inferior infarct. The left anterior descending supplies the anterior wall and septum, while the circumflex supplies the lateral wall. Left main occlusion typically produces extensive anterior and lateral injury rather than an isolated inferior pattern.

Question 45Cardiac Disorders and Clinical Management

Hypotension, distended neck veins, and muffled heart sounds together suggest which condition?

  1. Aortic stenosis
  2. Acute pericarditis
  3. Constrictive pericarditis
  4. Cardiac tamponade Correct answer.

Explanation

This combination is Beck triad, the classic presentation of cardiac tamponade, in which accumulating pericardial fluid impairs ventricular filling. Acute pericarditis causes positional pleuritic pain and diffuse ST elevation rather than shock with muffled sounds. Constrictive pericarditis produces venous congestion and edema but not the acute triad with hypotension and quiet heart sounds.

Question 46Cardiac Disorders and Clinical Management

Which laboratory marker is most specific for myocardial injury?

  1. Total creatine kinase
  2. Myoglobin
  3. Troponin I Correct answer.
  4. Lactate dehydrogenase

Explanation

Cardiac troponin I and T are structurally specific to myocardium and are the preferred markers for myocardial injury. Total creatine kinase, lactate dehydrogenase, and myoglobin also rise with skeletal muscle injury and are therefore less specific. Myoglobin rises early but is highly non-specific.

Question 47Cardiac Disorders and Clinical Management

Which rhythm is characterized by an irregularly irregular ventricular rate with no discernible P waves?

  1. Atrial flutter
  2. Sinus arrhythmia
  3. Ventricular tachycardia
  4. Atrial fibrillation Correct answer.

Explanation

Atrial fibrillation produces chaotic atrial activity, so there are no discrete P waves and the ventricular response is irregularly irregular. Atrial flutter typically shows regular sawtooth flutter waves, and sinus arrhythmia has identifiable P waves with phasic rate variation. Ventricular tachycardia is a regular wide-complex rhythm.

Question 48Cardiac Disorders and Clinical Management

Which assessment finding is most consistent with left-sided heart failure?

  1. Hepatomegaly
  2. Jugular venous distension
  3. Peripheral edema
  4. Pulmonary crackles Correct answer.

Explanation

Left-sided failure raises pulmonary capillary pressure, causing alveolar fluid accumulation with crackles, dyspnea, and orthopnea. Hepatomegaly, jugular venous distension, and peripheral edema reflect right-sided congestion. Isolated left-sided failure primarily manifests with pulmonary symptoms.

Question 49Cardiac Disorders and Clinical Management

A patient with ST-elevation myocardial infarction arrives at a hospital capable of primary percutaneous coronary intervention. What is the recommended maximum door-to-balloon time?

  1. 12 hours
  2. 90 minutes Correct answer.
  3. 180 minutes
  4. 30 minutes

Explanation

When primary PCI is available, reperfusion should be achieved within 90 minutes of hospital arrival to limit infarct size. The 30-minute benchmark applies to door-to-needle fibrinolysis, not to balloon inflation. A 12-hour figure refers to the outer window in which reperfusion may still be beneficial, not the institutional target.

Question 50Cardiac Disorders and Clinical Management

Which medication class should generally be avoided in a patient with symptomatic heart failure and reduced ejection fraction?

  1. Loop diuretics
  2. ACE inhibitors
  3. Beta-blockers
  4. Verapamil and diltiazem Correct answer.

Explanation

Non-dihydropyridine calcium channel blockers have negative inotropic effects and can precipitate decompensation in reduced ejection fraction. Loop diuretics are used to relieve congestion, and carvedilol, metoprolol succinate, and bisoprolol carry mortality benefit. ACE inhibitors are a cornerstone of therapy unless contraindicated.