A 27-year-old woman with no known structural heart disease presents to the outpatient clinic because of recurrent episodes of sudden-onset palpitations over the past year. Each episode begins and ends abruptly, lasts 10–30 minutes, and is sometimes associated with mild dizziness but no syncope. She reports that the episodes can occasionally be terminated by holding her breath and bearing down. During one episode recorded in the emergency department, her ECG demonstrates a narrow-complex tachycardia at 190 beats/min. P waves are not clearly discernible during tachycardia. After a modified Valsalva maneuver, the rhythm abruptly converts to normal sinus rhythm. Her baseline ECG shows no pre-excitation or conduction abnormalities. What is the most likely underlying electrophysiological mechanism responsible for this arrhythmia?

A 73-year-old man is evaluated after two episodes of unexplained syncope over the last three months. Both episodes occurred at rest and were preceded by brief lightheadedness without chest pain or palpitations. His medications include amlodipine for hypertension. Physical examination is unremarkable. Baseline ECG shows sinus rhythm at 62 beats/min with no AV block. A 48-hour Holter monitor reveals multiple sinus pauses, the longest lasting 6.8 seconds, occurring predominantly during daytime hours and correlating with symptoms recorded in the patient diary. Which of the following is the most appropriate definitive treatment?

A 56-year-old woman is admitted to the coronary care unit for recurrent episodes of syncope. Telemetry shows runs of polymorphic ventricular tachycardia. Her ECG demonstrates a prolonged QT interval of 540 ms. Laboratory tests reveal potassium 3.1 mmol/L and magnesium 1.4 mg/dL. She was started on sotalol three days earlier for atrial fibrillation. Which of the following is the most appropriate immediate management?

A 41-year-old man presents after a witnessed syncopal episode while walking. He has no prior medical history. His brother died suddenly at the age of 29 during sleep. ECG shows coved ST-segment elevation ≥2 mm in leads V1–V3 followed by negative T waves. Echocardiography shows no structural heart disease. Which of the following is the most appropriate long-term management strategy for this patient?

A 69-year-old woman with a history of long-standing hypertension and heart failure with preserved ejection fraction presents with acute onset dyspnea and orthopnea that started 2 hours ago. What is the most likely cause of her symptoms?

A 62-year-old man is admitted for evaluation of recurrent presyncope. He reports several episodes of near-fainting over the past month, often occurring without warning. He denies chest pain or palpitations. His medical history is unremarkable. Physical examination is normal. Baseline ECG shows sinus rhythm with alternating right and left bundle branch block on serial tracings. Echocardiography reveals normal left ventricular systolic function and no structural heart disease.

A 58-year-old man with a known history of Wolff–Parkinson–White syndrome presents with sudden-onset palpitations and dizziness. On arrival, his blood pressure is 105/70 mmHg. ECG shows an irregular wide-complex tachycardia with varying QRS morphology and a ventricular rate of approximately 220 beats/min.

A 74-year-old man with ischemic cardiomyopathy (LVEF 30%) presents after an episode of sudden cardiac arrest at home. He was successfully resuscitated from ventricular fibrillation by emergency medical services. Coronary angiography shows no acute culprit lesion. After stabilization, he is neurologically intact.

A 45-year-old man with hypertrophic cardiomyopathy presents with worsening exertional dyspnea and presyncope. Echocardiography demonstrates asymmetric septal hypertrophy and a resting left ventricular outflow tract gradient of 90 mmHg. Blood pressure is 110/70 mmHg.

A 61-year-old man presents to the emergency department 90 minutes after the onset of severe retrosternal chest pain radiating to his left arm. ECG shows ST-segment elevation in leads V2–V5. He is hemodynamically stable. The hospital has 24-hour PCI capability with an experienced interventional team available immediately.

A 67-year-old woman presents with chest discomfort and nausea. ECG shows ST-segment depression in leads V4–V6. High-sensitivity troponin is elevated. Her GRACE risk score is calculated at 165. Blood pressure is stable. According to current guidelines, when should coronary angiography be performed?

A 59-year-old man with acute chest pain has ECG showing horizontal ST-segment depression in leads V1–V3 with tall R waves. Posterior leads V7–V9 show ST elevation. This ECG pattern is most consistent with which diagnosis?

A 64-year-old man develops hypotension and cool extremities following a large anterior myocardial infarction. Pulmonary artery catheterization reveals a cardiac index of 1.9 L/min/m² and elevated filling pressures. Which of the following findings is most strongly associated with poor short-term prognosis?

A patient with acute coronary syndrome undergoes drug-eluting stent implantation. He has a history of gastrointestinal bleeding one year ago. Which antiplatelet strategy is most appropriate to reduce bleeding risk while maintaining ischemic protection?

A 55-year-old woman presents with chest pain and elevated troponin levels. Coronary angiography reveals non-obstructive coronary arteries. Cardiac MRI later demonstrates subendocardial late gadolinium enhancement.

A 72-year-old man develops acute hypotension and new harsh holosystolic murmur 4 days after an inferior myocardial infarction. Pulmonary edema rapidly ensues.

A patient with inferior STEMI becomes hypotensive shortly after admission. Jugular venous pressure is elevated, and lung fields are clear on auscultation. ECG shows ST elevation in leads II, III, and aVF.

Which diagnosis best explains this presentation?

A 60-year-old man presents with NSTEMI and newly diagnosed atrial fibrillation. He undergoes PCI with drug-eluting stent implantation. He has moderate bleeding risk. Which antithrombotic regimen is preferred?

A 68-year-old man presents with cardiogenic shock complicating acute myocardial infarction. Despite adequate fluid resuscitation, hypotension persists. Which vasopressor is recommended as first-line therapy?

A 72-year-old man with known ischemic cardiomyopathy (LVEF 25%) presents to the emergency department with progressive dyspnea, orthopnea, and decreased urine output over the past 24 hours. On examination, he is confused and diaphoretic. Blood pressure is 88/56 mmHg, heart rate 112 beats/min, respiratory rate 26 breaths/min, and oxygen saturation 91% on nasal cannula. Jugular venous pressure is elevated, lungs reveal diffuse crackles, and extremities are cold and clammy. Pulmonary artery catheterization shows: • Cardiac index: 1.6 L/min/m² • Pulmonary capillary wedge pressure: 28 mmHg • Systemic vascular resistance: elevated. Which hemodynamic profile best describes this patient?

In the patient described above, which initial management strategy is most appropriate?

A 64-year-old woman with acute decompensated heart failure is started on intravenous nitrates for severe pulmonary congestion. Shortly after initiation, she develops hypotension. Bedside echocardiography shows a small left ventricular cavity with near-complete inferior vena cava collapse.

Which therapy provides early mortality benefit and should be initiated before hospital discharge?

A 61-year-old man with anterior STEMI complicated by cardiogenic shock remains hypotensive despite adequate volume status, norepinephrine infusion, and dobutamine. Lactate is rising and cardiac index remains 1.5 L/min/m². What is the most evidence-based next step?

A patient with acute decompensated heart failure develops a rise in serum creatinine from 1.3 mg/dL to 2.1 mg/dL during aggressive diuretic therapy. Clinical examination still shows marked congestion. What is the most appropriate interpretation?

A 68-year-old man presents with acute cardiogenic pulmonary edema. Despite high-flow oxygen, he remains hypoxemic. Arterial blood gas shows pH 7.48, PaCO₂ 30 mmHg, PaO₂ 58 mmHg. What is the most appropriate ventilatory strategy?

A 33-year-old woman presents 2 weeks postpartum with progressive dyspnea and lower extremity edema. Echocardiography reveals LVEF 30% with global hypokinesia and left ventricular dilation. She is breastfeeding.

A 70-year-old man with chronic HFrEF (EF 28%) remains NYHA class III despite optimal guideline-directed medical therapy. ECG shows QRS duration 96 ms with non–left bundle branch block morphology. Which of the following therapies is NOT indicated?

A 65-year-old man with ischemic cardiomyopathy has severe secondary mitral regurgitation despite optimized guideline-directed medical therapy. He has had multiple hospitalizations for heart failure. Surgical risk is deemed prohibitive. Which intervention has been shown to improve outcomes in appropriately selected patients?

A 58-year-old man presents with fulminant myocarditis complicated by cardiogenic shock. Coronary angiography is normal. He requires escalating doses of inotropes and vasopressors to maintain perfusion.

A patient presents with hypotension, elevated jugular venous pressure, hepatomegaly, and clear lung fields. Echocardiography shows severely reduced right ventricular function with preserved left ventricular systolic function.

A 75-year-old man with end-stage heart failure has been hospitalized four times in the past six months despite optimal guideline-directed medical therapy. He reports poor quality of life and frequent dyspnea at rest. What is the most appropriate next step in management?

A patient with heart failure and reduced ejection fraction develops sustained monomorphic ventricular tachycardia during hospitalization. He is successfully cardioverted and stabilized. Which long-term strategy is most appropriate to prevent recurrence and reduce mortality?

A hospitalized patient suddenly collapses. Telemetry shows ventricular fibrillation. What is the single most important immediate action?

During high-quality cardiopulmonary resuscitation, end-tidal CO2 persistently remains below 10 mmHg. This finding most strongly indicates:

Which of the following rhythms is classified as non-shockable in advanced cardiac life support algorithms?

A patient with symptomatic bradycardia remains hypotensive and confused despite atropine administration. What is the next recommended intervention?

A patient with septic shock develops new-onset atrial fibrillation and becomes hemodynamically unstable. What is the best immediate management?

A patient survives out-of-hospital cardiac arrest due to ventricular fibrillation. Coronary angiography shows no obstructive coronary disease. LVEF is 35%. What is the most appropriate secondary prevention strategy?

A 76-year-old man presents with progressive exertional dyspnea and two recent episodes of exertional presyncope. A harsh late-peaking systolic murmur is heard at the right upper sternal border radiating to the carotids. Echocardiography shows: AVA 0.7 cm², mean gradient 34 mmHg, LVEF 40%, stroke volume index 28 mL/m².

In the patient above, which diagnostic test is most appropriate to differentiate true severe aortic stenosis from pseudosevere aortic stenosis?

A 69-year-old woman with long-standing atrial fibrillation presents with worsening dyspnea. Echocardiography reveals severe mitral stenosis (valve area 0.9 cm²), marked leaflet calcification, and Wilkins score 11. What is the most appropriate definitive treatment?

A 71-year-old man with severe degenerative mitral regurgitation due to a flail posterior leaflet presents with NYHA class III symptoms. LVEF is 60% with LVESD 36 mm. What is the most appropriate management strategy?

Which echocardiographic finding most strongly supports the diagnosis of severe primary mitral regurgitation?

A 66-year-old man with ischemic cardiomyopathy (LVEF 30%) has severe secondary mitral regurgitation despite maximally tolerated guideline-directed medical therapy. He has had two hospitalizations for heart failure in the past year. Echocardiographic parameters fulfill COAPT trial criteria. Which intervention has been shown to improve outcomes in this patient population?

A 73-year-old woman with severe tricuspid regurgitation presents with ascites and peripheral edema. Echocardiography shows severe annular dilation and preserved right ventricular systolic function. She is scheduled to undergo mitral valve surgery. What is the most appropriate management of the tricuspid valve?

A 62-year-old man develops sudden pulmonary edema and hypotension three days after an inferior myocardial infarction. A new loud holosystolic murmur is heard at the apex. Echocardiography suggests acute severe mitral regurgitation.

A 50-year-old woman with repaired tetralogy of Fallot presents with progressive exercise intolerance. Echocardiography shows severe pulmonary regurgitation and progressive right ventricular dilation, but preserved right ventricular systolic function. What is the most appropriate timing for pulmonary valve intervention?

A 67-year-old man with a mechanical mitral valve presents with acute dyspnea and hypotension. His INR is 1.5. Echocardiography suggests obstructive prosthetic valve thrombosis.

A 79-year-old man with symptomatic severe aortic stenosis is evaluated for valve replacement. He has high surgical risk due to frailty and chronic kidney disease. CT imaging shows favorable vascular access. Which treatment strategy is most appropriate?

A patient with severe aortic stenosis has recurrent gastrointestinal bleeding from angiodysplasia (Heyde syndrome). What effect does aortic valve replacement most commonly have on bleeding risk?

A 34-year-old woman with an unrepaired secundum atrial septal defect presents with exertional dyspnea and cyanosis. Echocardiography shows bidirectional shunting and severe pulmonary hypertension.

A 29-year-old woman with repaired ventricular septal defect presents for pre-pregnancy counseling. She is asymptomatic with normal ventricular function. Which statement is most accurate?

A 56-year-old man presents with progressive dyspnea. Echocardiography shows concentric LV hypertrophy, biatrial enlargement, and restrictive filling pattern. Cardiac MRI shows diffuse subendocardial late gadolinium enhancement.

Which echocardiographic feature most strongly favors constrictive pericarditis over restrictive cardiomyopathy?

A 61-year-old man presents with exertional chest pain. Coronary angiography shows a 60% stenosis in the mid-LAD. Fractional flow reserve (FFR) is measured at 0.84. What is the most appropriate management?

Which is the correct answer?

A 63-year-old woman with chronic kidney disease requires ischemia evaluation. Minimizing contrast and radiation exposure is a priority. Which test is most appropriate?

A patient develops a new holosystolic murmur and acute pulmonary edema following myocardial infarction. Transthoracic echocardiography is suboptimal. What is the best next diagnostic step?

A 60-year-old man undergoes right heart catheterization. Which parameter best reflects preload?

A 70-year-old man with a long history of smoking and diabetes mellitus presents with progressively worsening pain in his left foot over the past two weeks. He reports rest pain at night that is relieved only when he dangles his leg over the side of the bed. Physical examination reveals a non-healing ulcer on the left great toe. Femoral pulse is palpable, but distal pulses are absent. Ankle-brachial Index is 0.32.

A 65-year-old woman presents with sudden onset of severe pain, pallor, and numbness in her right leg that began 3 hours ago. On examination, the leg is cold, pulseless, and she has reduced motor function of the foot. What is the most important immediate management step?

A 59-year-old man presents with abrupt onset of tearing chest pain radiating to the back. Blood pressure is 180/95 mmHg. CT angiography reveals a Stanford type B aortic dissection extending from the distal left subclavian artery to the abdominal aorta, without evidence of rupture or malperfusion. What is the most appropriate initial management?

Which finding in a patient with acute Stanford type B aortic dissection mandates urgent endovascular or surgical intervention?

A 54-year-old woman presents with sudden dyspnea, pleuritic chest pain, and syncope. Blood pressure is 78/48 mmHg, heart rate 128 beats/min, and oxygen saturation 86% on room air. CT pulmonary angiography confirms massive pulmonary embolism.

Which patient with pulmonary embolism is most likely to benefit from catheter-directed thrombolytic therapy?

A 62-year-old man with a history of deep vein thrombosis presents months later with progressive exertional dyspnea and reduced exercise tolerance. Ventilation–perfusion scanning reveals multiple mismatched segmental perfusion defects.

In eligible patients with chronic thromboembolic pulmonary hypertension, which intervention offers the greatest potential for cure?

A 66-year-old man with atrial fibrillation on inconsistent anticoagulation presents with acute onset of severe abdominal pain, nausea, and vomiting. Physical examination reveals minimal abdominal tenderness despite severe pain. Laboratory testing shows metabolic acidosis and elevated lactate. CT angiography demonstrates an embolus in the superior mesenteric artery.

A 71-year-old woman presents with transient right-sided weakness and aphasia lasting 20 minutes. She has a history of atrial fibrillation but declined anticoagulation. Brain MRI shows no acute infarction.

A 58-year-old man with nonvalvular atrial fibrillation has recurrent embolic events despite therapeutic anticoagulation. Transesophageal echocardiography reveals a large thrombus in the left atrial appendage. Which additional strategy may be considered in selected patients?

A patient develops painful blue discoloration of the toes, livedo reticularis, and acute kidney injury several days after coronary angiography. What is the most likely diagnosis?

A 63-year-old man with intermittent claudication continues to have lifestyle-limiting symptoms despite optimal medical therapy and supervised exercise. Imaging shows a focal iliac artery stenosis. What is the most appropriate revascularization strategy?

A 60-year-old woman presents with acute chest pain. CT angiography reveals an intramural hematoma of the ascending aorta. What is the most appropriate management?

A 55-year-old man presents with acute tearing chest pain radiating to the back. Imaging shows Stanford type A aortic dissection. What is the recommended management?

A patient with pulmonary embolism is hemodynamically stable but has right ventricular dilation on echocardiography and elevated cardiac biomarkers. How should this PE be classified?

Which laboratory or imaging finding best reflects right ventricular dysfunction in acute pulmonary embolism?

A 68-year-old man with atrial fibrillation presents with acute unilateral visual loss. Fundoscopy shows a pale retina with a cherry-red spot. What is the most likely diagnosis?

A 64-year-old man with atrial fibrillation and CHA2DS2-VASc score of 5 refuses long-term oral anticoagulation. Which evidence-based alternative may reduce stroke risk?

A 67-year-old man presents with progressive exertional dyspnea. Echocardiography shows preserved LVEF, enlarged left atrium, and elevated E/e' ratio. Right heart catheterization shows mean pulmonary artery pressure 28 mmHg and pulmonary capillary wedge pressure 20 mmHg.

A 66-year-old man presents with exertional dyspnea. Transthoracic echocardiography shows a left ventricular ejection fraction of 50%. Tissue Doppler imaging demonstrates reduced systolic velocities, while conventional measures appear borderline normal. Which echocardiographic parameter is most sensitive for detecting early left ventricular systolic dysfunction?

A 58-year-old man with suspected infective endocarditis has persistent fever and positive blood cultures for Staphylococcus aureus. Transthoracic echocardiography does not reveal vegetations. What is the most appropriate next imaging study?

A 70-year-old woman presents with unexplained exertional dyspnea. Echocardiography shows preserved LVEF, enlarged left atrium, and an E/e' ratio of 19. BNP is mildly elevated. Which diagnosis best explains these findings?

A patient presents to the emergency department with acute chest pain and hypotension. Bedside echocardiography reveals a dilated right ventricle with interventricular septal flattening creating a "D-shaped" left ventricle. Which diagnosis is most consistent with these findings?

A 62-year-old man undergoes coronary angiography. A visually estimated 55% stenosis is found in the mid-left anterior descending artery. He has stable angina symptoms. Which invasive physiologic assessment best guides the need for revascularization?

In a patient with stable coronary artery disease, which fractional flow reserve (FFR) value supports deferral of percutaneous coronary intervention?

A 64-year-old man with chronic kidney disease requires ischemia evaluation. Minimizing contrast exposure and radiation is a priority. Which diagnostic modality is most appropriate?

A patient develops a new loud holosystolic murmur and acute pulmonary edema two days after myocardial infarction. Transthoracic echocardiography is suboptimal. What is the best next diagnostic step?

A 32-year-old woman with a mechanical mitral valve becomes pregnant. She presents at 8 weeks' gestation and is concerned about anticoagulation management. Which anticoagulation strategy is most appropriate during the first trimester?

A pregnant woman presents with sudden dyspnea and pleuritic chest pain. Pulmonary embolism is suspected. She is hemodynamically stable, and chest X-ray is normal. Which imaging test is preferred to balance diagnostic accuracy and fetal radiation exposure?

A 45-year-old woman with hypertrophic cardiomyopathy reports syncope and has a family history of sudden cardiac death. Echocardiography shows marked septal hypertrophy. Which intervention most effectively reduces mortality?

A 57-year-old man presents with chest pain following a viral upper respiratory infection. ECG shows diffuse ST-segment elevation with PR depression. Cardiac biomarkers are mildly elevated. What is the most likely diagnosis?

Which feature most strongly favors myocarditis over acute coronary syndrome?

A patient with constrictive pericarditis is evaluated. Which echocardiographic finding is most characteristic?

A patient with heart failure and chronic kidney disease experiences a transient rise in serum creatinine during aggressive diuresis, but clinical congestion improves. What is the most appropriate management strategy?

According to current guidelines, what is the recommended LDL-cholesterol target for very high-risk atherosclerotic cardiovascular disease patients?

A 60-year-old man enters a structured cardiac rehabilitation program after myocardial infarction. Which component provides the greatest mortality benefit?

Which of the following is a contraindication to exercise stress testing?