HESI CARDIAC NURSING
PRACTICE TEST 2026 QUESTIONS
AND ANSWERS WITH
RATIONALES/GRADED A+/2026
UPDATE/100% CORRECT
/INSTANT DOWNLOAD
SECTION 1: Anatomy & Physiology (Questions 1-10)
1. The coronary artery that supplies blood to the left ventricle, intraventricular
septum, and part of the right ventricle is the:
• A) Right coronary artery
• B) Left anterior descending artery ✅
• C) Circumflex artery
• D) Posterior descending artery
Rationale: The LAD (also called the anterior interventricular artery) supplies a large
territory including the anterior wall of the left ventricle, the intraventricular septum,
and portions of the right ventricle. Occlusion of this artery is often called the "widow
maker" due to high mortality.
2. Which phase of the cardiac cycle represents ventricular contraction and ejection of
blood?
• A) Diastole
• B) Systole ✅
• C) Isovolumetric relaxation
• D) Rapid filling phase
Rationale: Systole is the phase where the ventricles contract, pressure rises above
atrial pressure, AV valves close (S1 heart sound), and blood is ejected into the
pulmonary artery and aorta.
,3. The intrinsic heart rate set by the SA node is approximately:
• A) 40-60 bpm
• B) 60-100 bpm ✅
• C) 100-120 bpm
• D) 20-40 bpm
Rationale: The sinoatrial (SA) node, the primary pacemaker, normally fires at 60-100
beats per minute. The AV node has an intrinsic rate of 40-60 bpm, and Purkinje fibers
20-40 bpm.
4. Which valve prevents backflow of blood from the aorta into the left ventricle?
• A) Mitral valve
• B) Tricuspid valve
• C) Pulmonary valve
• D) Aortic valve ✅
Rationale: The aortic valve is a semilunar valve located between the left ventricle and
aorta. It opens during systole to allow blood ejection and closes during diastole to
prevent regurgitation back into the left ventricle.
5. The layer of the heart responsible for the contraction force is the:
• A) Epicardium
• B) Myocardium ✅
• C) Endocardium
• D) Pericardium
Rationale: The myocardium is the middle, muscular layer of the heart wall composed
of cardiac muscle cells (cardiomyocytes) that contract to pump blood. The
epicardium is the outer layer, endocardium lines the chambers, and pericardium is
the protective sac.
6. Cardiac output is calculated as:
• A) Heart rate × Blood pressure
• B) Heart rate × Stroke volume ✅
• C) Stroke volume × Systemic vascular resistance
• D) Blood pressure × Systemic vascular resistance
Rationale: Cardiac output (CO) = Heart rate (HR) × Stroke volume (SV). Normal CO is
4-8 L/min. Stroke volume is affected by preload, afterload, and contractility.
7. The P wave on an ECG represents:
, • A) Ventricular depolarization
• B) Atrial depolarization ✅
• C) Ventricular repolarization
• D) AV nodal delay
Rationale: The P wave represents electrical activation (depolarization) of the atria,
leading to atrial contraction. The PR segment reflects AV nodal delay, QRS complex is
ventricular depolarization, and T wave is ventricular repolarization.
8. Which coronary artery typically supplies the SA node in 60% of the population?
• A) Right coronary artery ✅
• B) Left main coronary artery
• C) Left anterior descending artery
• D) Circumflex artery
Rationale: The right coronary artery (RCA) supplies the SA node in approximately
60% of individuals (right-dominant circulation), the circumflex artery supplies it in
40% (left-dominant circulation).
9. Preload is best defined as:
• A) Resistance the left ventricle must overcome to eject blood
• B) Volume of blood in the ventricles at end-diastole ✅
• C) Force of ventricular contraction
• D) Pressure in the aorta during systole
Rationale: Preload is the degree of myocardial stretch just before contraction,
determined by end-diastolic volume. It follows the Frank-Starling law: increased
preload increases stroke volume up to a point.
10. The second heart sound (S2) corresponds to:
• A) Closure of AV valves (mitral and tricuspid)
• B) Closure of semilunar valves (aortic and pulmonary) ✅
• C) Ventricular filling
• D) Atrial contraction
Rationale: S2, "dub," occurs at the beginning of diastole when the aortic and
pulmonary valves close. S2 splits physiologically during inspiration due to delayed
pulmonic valve closure.
PRACTICE TEST 2026 QUESTIONS
AND ANSWERS WITH
RATIONALES/GRADED A+/2026
UPDATE/100% CORRECT
/INSTANT DOWNLOAD
SECTION 1: Anatomy & Physiology (Questions 1-10)
1. The coronary artery that supplies blood to the left ventricle, intraventricular
septum, and part of the right ventricle is the:
• A) Right coronary artery
• B) Left anterior descending artery ✅
• C) Circumflex artery
• D) Posterior descending artery
Rationale: The LAD (also called the anterior interventricular artery) supplies a large
territory including the anterior wall of the left ventricle, the intraventricular septum,
and portions of the right ventricle. Occlusion of this artery is often called the "widow
maker" due to high mortality.
2. Which phase of the cardiac cycle represents ventricular contraction and ejection of
blood?
• A) Diastole
• B) Systole ✅
• C) Isovolumetric relaxation
• D) Rapid filling phase
Rationale: Systole is the phase where the ventricles contract, pressure rises above
atrial pressure, AV valves close (S1 heart sound), and blood is ejected into the
pulmonary artery and aorta.
,3. The intrinsic heart rate set by the SA node is approximately:
• A) 40-60 bpm
• B) 60-100 bpm ✅
• C) 100-120 bpm
• D) 20-40 bpm
Rationale: The sinoatrial (SA) node, the primary pacemaker, normally fires at 60-100
beats per minute. The AV node has an intrinsic rate of 40-60 bpm, and Purkinje fibers
20-40 bpm.
4. Which valve prevents backflow of blood from the aorta into the left ventricle?
• A) Mitral valve
• B) Tricuspid valve
• C) Pulmonary valve
• D) Aortic valve ✅
Rationale: The aortic valve is a semilunar valve located between the left ventricle and
aorta. It opens during systole to allow blood ejection and closes during diastole to
prevent regurgitation back into the left ventricle.
5. The layer of the heart responsible for the contraction force is the:
• A) Epicardium
• B) Myocardium ✅
• C) Endocardium
• D) Pericardium
Rationale: The myocardium is the middle, muscular layer of the heart wall composed
of cardiac muscle cells (cardiomyocytes) that contract to pump blood. The
epicardium is the outer layer, endocardium lines the chambers, and pericardium is
the protective sac.
6. Cardiac output is calculated as:
• A) Heart rate × Blood pressure
• B) Heart rate × Stroke volume ✅
• C) Stroke volume × Systemic vascular resistance
• D) Blood pressure × Systemic vascular resistance
Rationale: Cardiac output (CO) = Heart rate (HR) × Stroke volume (SV). Normal CO is
4-8 L/min. Stroke volume is affected by preload, afterload, and contractility.
7. The P wave on an ECG represents:
, • A) Ventricular depolarization
• B) Atrial depolarization ✅
• C) Ventricular repolarization
• D) AV nodal delay
Rationale: The P wave represents electrical activation (depolarization) of the atria,
leading to atrial contraction. The PR segment reflects AV nodal delay, QRS complex is
ventricular depolarization, and T wave is ventricular repolarization.
8. Which coronary artery typically supplies the SA node in 60% of the population?
• A) Right coronary artery ✅
• B) Left main coronary artery
• C) Left anterior descending artery
• D) Circumflex artery
Rationale: The right coronary artery (RCA) supplies the SA node in approximately
60% of individuals (right-dominant circulation), the circumflex artery supplies it in
40% (left-dominant circulation).
9. Preload is best defined as:
• A) Resistance the left ventricle must overcome to eject blood
• B) Volume of blood in the ventricles at end-diastole ✅
• C) Force of ventricular contraction
• D) Pressure in the aorta during systole
Rationale: Preload is the degree of myocardial stretch just before contraction,
determined by end-diastolic volume. It follows the Frank-Starling law: increased
preload increases stroke volume up to a point.
10. The second heart sound (S2) corresponds to:
• A) Closure of AV valves (mitral and tricuspid)
• B) Closure of semilunar valves (aortic and pulmonary) ✅
• C) Ventricular filling
• D) Atrial contraction
Rationale: S2, "dub," occurs at the beginning of diastole when the aortic and
pulmonary valves close. S2 splits physiologically during inspiration due to delayed
pulmonic valve closure.
