Cardiology
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Cardiology
Practical cardiology guides for clinical decisions, with cited evidence, testing strategies, and actionable next steps.
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Cardiology
ST-Segment Elevation Myocardial Infarction
ST-segment elevation myocardial infarction requires immediate ECG-based activation, reperfusion-centered care, and early recognition of shock, failed fibrinolysis, mechanical complications, and nonatherothrombotic mimics that alter acute management.Cardiology
Heart Failure
Heart failure requires phenotype-specific confirmation, rapid identification of reversible precipitants, early disease-modifying therapy for reduced ejection fraction, and surveillance for congestion, arrhythmia, renal dysfunction, and progression to advanced therapies. Management must align treatment intensity with hemodynamics, comorbidity, and patient goals.Cardiology
Myocardial Infarction
Myocardial infarction requires immediate ECG-based triage, assay-specific serial troponin interpretation, differentiation of ischemic infarction from myocardial injury, and rapid selection of reperfusion or invasive management. Post-event care should consolidate antithrombotic therapy, ventricular assessment, rehabilitation, and secondary prevention.Cardiology and cardiovascular surgery
Aortic Dissection
Aortic dissection requires rapid anatomic diagnosis, immediate anti-impulse therapy, and disposition determined by ascending-aortic involvement, rupture, malperfusion, and persistent symptoms. Computed tomographic angiography is first-line in most stable patients; type A disease requires emergency surgical evaluation, whereas uncomplicated type B disease begins with medical therapy.Cardiology
Heart Failure With Preserved Ejection Fraction
HFpEF requires objective evidence of heart failure beyond a preserved ejection fraction. Diagnose systematically, exclude cardiac and noncardiac mimics, use stress or invasive hemodynamics when uncertainty persists, decongest judiciously, initiate SGLT2 inhibition, and phenotype-directed therapy for obesity, CKD, atrial fibrillation, and hypertension.Cardiology
Atrial Fibrillation
A practical framework for confirming atrial fibrillation, defining acute stability, completing the initial evaluation, preventing thromboembolism, selecting rate or rhythm control, and identifying patients who benefit from catheter ablation or focused heart-failure management.Cardiology
Chest Pain
Evaluate acute chest pain with immediate ECG, high-sensitivity troponin, and structured risk pathways while actively excluding ACS, aortic syndromes, pulmonary embolism, and other lethal alternatives. Stable symptoms require contemporary pretest assessment and selective anatomic or functional testing rather than routine testing.Cardiology and Critical Care Medicine
Cardiogenic Shock
Cardiogenic shock requires immediate recognition of tissue hypoperfusion, rapid identification of a reversible cause, phenotype-directed vasoactive support, serial reassessment, and early escalation or transfer when pharmacologic support cannot preserve end-organ perfusion.Vascular Medicine
Deep Venous Thrombosis
Deep venous thrombosis requires structured pretest-probability assessment, selective D-dimer use, and timely compression ultrasonography. Management centers on therapeutic anticoagulation, determination of provoking factors and recurrence risk, and selective use of advanced interventions only when anticoagulation is contraindicated or clinical threat is exceptional.Cardiology and Infectious Diseases
Infective Endocarditis
Manage suspected infective endocarditis by obtaining diagnostic blood cultures before antibiotics, defining valve or device involvement with staged imaging, identifying heart failure or uncontrolled infection requiring urgent surgery, and tailoring antimicrobial therapy to microbiology with documented culture clearance.Cardiology and Infectious Diseases
Prosthetic Valve Endocarditis
Prosthetic valve endocarditis requires early culture-directed evaluation, transesophageal echocardiography, and selective CT or FDG-PET/CT to detect occult paravalvular infection and define urgency for valve surgery.Cardiology and Infectious Diseases
Infective Endocarditis Prophylaxis
Use a two-step decision: identify patients at highest risk of adverse endocarditis outcomes, then determine whether the planned dental procedure manipulates gingiva, periapical tissue, or oral mucosa. Give one preprocedure antibiotic dose only when both conditions are met.Cardiology and Clinical Cardiac Electrophysiology
Wolff-Parkinson-White Syndrome
Manage Wolff-Parkinson-White syndrome by recognizing pre-excited atrial fibrillation as an electrical emergency, avoiding AV-nodal blockers, and referring symptomatic or high-risk patients for electrophysiologic assessment and accessory-pathway ablation.Cardiology and Emergency Medicine
Syncope
Evaluate syncope by first identifying unstable cardiac, structural, pulmonary, hemorrhagic, or neurologic mimics; then use history, orthostatic vital signs, examination, and 12-lead ECG to direct selective testing, disposition, rhythm correlation, and cause-specific treatment.Cardiology
Aortic Stenosis
Aortic stenosis management hinges on confirming hemodynamic severity, resolving low-gradient discordance, and selecting valve replacement modality through anatomy, operative risk, life expectancy, concomitant disease, and transfemoral access.Cardiology
Mitral Regurgitation
A decision-focused approach to confirming severity, separating primary from secondary mitral regurgitation, selecting repair versus transcatheter therapy, and identifying patients whose ventricular remodeling or heart failure burden warrants multidisciplinary valve intervention.Cardiovascular Medicine
Essential Hypertension
A practical approach to confirm sustained hypertension with out-of-office measurement, stratify treatment thresholds by cardiovascular risk, avoid white-coat misclassification, and systematically distinguish apparent from true resistant hypertension before intensifying therapy.Cardiology
Hypertension Clinical Trials
Use hypertension trial evidence to select treatment thresholds and targets, verify uncontrolled blood pressure outside the office, intensify multidrug therapy appropriately, and reserve renal denervation for carefully selected patients after adherence, measurement, and secondary causes have been addressed.Pulmonology and Cardiology
Pulmonary Hypertension
Pulmonary hypertension requires invasive hemodynamic confirmation, separation of pre- from post-capillary physiology, and prompt identification of potentially curable chronic thromboembolic disease before PAH-targeted treatment is considered.Cardiology
Acute Myocarditis
Acute myocarditis requires rapid separation of uncomplicated inflammatory myocardial injury from acute coronary syndromes, fulminant shock, malignant arrhythmia, and biopsy-defined inflammatory syndromes requiring cause-directed immunosuppression or mechanical circulatory support.Cardiology
Coronary Artery Disease
Manage coronary artery disease by separating acute coronary syndrome from chronic coronary disease, selecting anatomy- or ischemia-directed testing for symptomatic patients, intensifying secondary prevention, and reserving revascularization for anatomically and clinically appropriate indications.Adult Congenital Heart Disease and Pulmonary Hypertension
Eisenmenger Syndrome
Eisenmenger syndrome requires confirmation of fixed pulmonary vascular disease and shunt physiology, exclusion of reversible mimics, avoidance of destabilizing interventions, and individualized PAH-directed therapy in an adult congenital heart disease–pulmonary hypertension center.Vascular Medicine
Inferior Vena Cava Syndrome
Inferior vena cava syndrome requires rapid distinction among acute iliocaval thrombosis, chronic obstruction, congenital anatomy, and malignant compression because anticoagulation, endovascular recanalization, oncologic treatment, and filter strategy differ substantially.Cardiology and Cardiac Electrophysiology
Long QT Syndrome
A practical framework for confirming congenital long QT syndrome, excluding acquired QT prolongation, identifying concealed disease, initiating genotype-informed arrhythmic risk reduction, and escalating to sympathetic denervation or defibrillator-based protection when breakthrough events persist.Cardiology
Rheumatic Heart Disease
Rheumatic heart disease requires parallel prevention of recurrent acute rheumatic fever, lesion-specific valve surveillance, anticoagulation when indicated, and early referral for catheter-based or surgical intervention before irreversible pulmonary vascular or ventricular consequences develop.Cardiology
Sick Sinus Syndrome
Diagnose sick sinus syndrome by documenting a temporal correlation between hypoperfusion symptoms and sinus-node dysfunction, after reversible causes are addressed. Permanent pacing is primarily a symptom-relief intervention for symptomatic bradycardia, chronotropic incompetence, or essential drug-related bradycardia.Vascular Medicine
Subclavian Steal Syndrome
Evaluate suspected subclavian steal with bilateral arm pressures and vertebral-subclavian duplex, then define arch-vessel anatomy by CTA or MRA before revascularizing patients with posterior-circulation ischemia, disabling arm ischemia, coronary steal, or hemodialysis-access dysfunction.Cardiovascular Medicine
Superior Vena Cava Syndrome
Superior vena cava syndrome requires rapid recognition of airway or cerebral compromise, contrast imaging to define obstruction, and etiologic triage between malignancy, device-associated thrombosis or stenosis, and less common mediastinal disorders.Cardiology and Nephrology
Cardiorenal Syndrome
Cardiorenal syndrome requires phenotype-based management: distinguish congestion from hypoperfusion, establish whether cardiac, renal, or systemic disease is primary, and pursue decongestion without reflexively abandoning therapy for a creatinine rise.Cardiology and Internal Medicine
Secondary Hypertension
Identify secondary hypertension when presentation, treatment resistance, or target-organ injury suggests a remediable cause; confirm true resistance, remove iatrogenic contributors, then prioritize renal disease, primary aldosteronism, obstructive sleep apnea, renovascular disease, and selected endocrine disorders.Cardiovascular Medicine
Metabolic Syndrome
Identify metabolic syndrome with a five-component screen, then treat the cardiovascular-kidney-metabolic risk profile rather than the label. Prioritize weight reduction, blood pressure and glycemic control, dyslipidemia management, kidney assessment, and PREVENT-based risk discussions to prevent diabetes, cardiovascular disease, and kidney disease progression.Cardiology and Critical Care
Cardiac Tamponade
Cardiac tamponade is a clinical obstructive-shock syndrome requiring rapid bedside echocardiographic assessment, recognition of context-dependent sonographic findings, and urgent drainage when impaired cardiac filling causes hemodynamic compromise.Emergency Medicine and Cardiology
Ventricular Fibrillation
Ventricular fibrillation requires immediate defibrillation, uninterrupted high-quality CPR between shocks, protocolized epinephrine and antiarrhythmic therapy when shock-refractory, and rapid reassessment for recurrent versus persistent VF. Refractory cases require center-specific escalation decisions, including alternative pad vectors and selected extracorporeal CPR pathways.Cardiology and Internal Medicine
Resistant Hypertension Secondary Cause Testing
In apparent resistant hypertension, first confirm sustained out-of-office blood pressure elevation and treatment exposure, then pursue targeted testing for primary aldosteronism, obstructive sleep apnea, kidney disease, renovascular disease, medication effects, and selected endocrine disorders.Cardiology
ACS Antithrombotic Selection
Select antithrombotic therapy in acute coronary syndrome by matching invasive timing, ischemic risk, bleeding risk, age, and chronic anticoagulation needs to an initial DAPT and anticoagulation strategy, then deliberately plan post-PCI aspirin withdrawal, P2Y12 choice, and treatment duration.Cardiology
Dual Antiplatelet Therapy After PCI
Select DAPT duration after PCI by first separating ACS from chronic coronary syndrome, then weighing bleeding risk, oral anticoagulation, and residual ischemic or procedural risk. Short DAPT followed by P2Y12 monotherapy is appropriate in selected patients; 12 months remains the ACS default.Cardiology
Atrial Fibrillation Rhythm Control Selection
Select rhythm control by first confirming that symptom relief, AF-mediated heart failure, or early disease modification justifies sinus-rhythm pursuit; then match antiarrhythmic drugs or catheter ablation to AF pattern, heart failure status, drug tolerance, procedural risk, and anticoagulation requirements.Cardiology and emergency medicine
Temporary Pacing for Bradycardia
Use temporary pacing for hemodynamically unstable bradycardia, high-grade conduction disease, or impending bradyasystolic collapse when pharmacologic reversal is ineffective, inappropriate, or too slow. Select transcutaneous pacing for immediate bridging and transvenous pacing when reliable support must continue.Cardiology and Emergency Medicine
Wide Complex Tachycardia
Manage any adult wide complex tachycardia by first identifying instability and delivering synchronized cardioversion when needed. In stable patients, obtain a 12-lead ECG, presume ventricular tachycardia until evidence supports another mechanism, and avoid AV-nodal blockade when pre-excitation is possible.Cardiology
Aortic Stenosis Intervention Thresholds
Replace the valve promptly for symptomatic severe aortic stenosis or LVEF below 50%; in apparently asymptomatic disease, confirm severity and use exercise testing, velocity progression, BNP, and life expectancy to determine whether surveillance remains appropriate.Cardiology
Atrial Fibrillation Anticoagulant Selection
Select stroke-prevention therapy in atrial fibrillation by confirming the indication for long-term anticoagulation, identifying patients who require warfarin, avoiding unsupported dose reduction, and considering left atrial appendage closure only when sustained anticoagulation is not feasible.Cardiology
Atrial Fibrillation Rate Control
For atrial fibrillation with heart failure, select rate-control therapy by hemodynamic status, ventricular function, activity-related tachycardia, and drug tolerance; a resting rate below 110 beats/min is generally a practical initial target in stable permanent AF.Cardiology
AF Cardioversion Anticoagulation
For elective cardioversion of atrial fibrillation lasting 48 hours or longer or of uncertain duration, establish uninterrupted therapeutic anticoagulation for 3 weeks or exclude intracardiac thrombus by imaging, then continue anticoagulation for at least 4 weeks after restoration of sinus rhythm.Emergency Medicine and Cardiology
Chest Pain Troponin Interpretation
Interpret high-sensitivity troponin with the ECG, symptom timing, serial change, and assay-specific thresholds—not as an isolated binary test—to distinguish acute myocardial infarction, acute nonischemic injury, chronic myocardial injury, and patients eligible for safe ED discharge.Cardiology
Acute Heart Failure Diuretic Escalation
Use an early intravenous loop-diuretic response assessment to distinguish underdosing from true resistance, double inadequate doses promptly, then add sequential nephron blockade selectively while monitoring renal function and electrolytes. Reserve ultrafiltration for failure of a stepped pharmacologic strategy.Emergency Medicine and Cardiovascular Medicine
Pulmonary Embolism Risk Stratification
Risk stratification in acute pulmonary embolism separates patients requiring immediate reperfusion from those appropriate for anticoagulation, monitored escalation, or outpatient care by integrating hemodynamics, clinical severity scores, right-ventricular assessment, and cardiac biomarkers.Cardiology and Pulmonary Medicine
Pulmonary Embolism Thrombolysis Selection
Select reperfusion therapy by hemodynamic status, RV injury, and bleeding risk: systemic thrombolysis remains standard for high-risk PE, whereas anticoagulation with monitored rescue escalation is preferred for most normotensive intermediate-risk patients.Infectious Diseases and Cardiology
Endocarditis Blood Culture Strategy
Obtain adequately collected peripheral blood cultures before antibiotics whenever clinical stability permits, then use pathogen, initial culture burden, clearance, and imaging to determine whether endocarditis evaluation must escalate.Cardiology
Arrhythmogenic Right Ventricular Cardiomyopathy
Diagnose ARVC by integrating ventricular arrhythmia phenotype, ECG, quantitative right-ventricular imaging, and family or genetic data; then reduce exercise exposure, assess individualized ventricular-arrhythmia risk, and select ICD-based prevention for patients whose projected risk justifies device morbidity.Cardiology
Atherosclerosis
Manage atherosclerosis as established or high-risk subclinical ASCVD: identify the affected vascular bed, intensify LDL-C reduction, use coronary calcium selectively when treatment is uncertain, and escalate beyond statins when residual LDL-C remains at least 70 mg/dL.Cardiology
Atrial Flutter
Atrial flutter requires rapid distinction between hemodynamic instability, typical cavotricuspid-isthmus–dependent flutter amenable to ablation, and atypical post–left atrial ablation circuits. Stroke prevention follows atrial fibrillation principles, while long-term surveillance remains essential after apparently successful flutter ablation.Cardiology
Atrial Septal Defect
Evaluate ASD by anatomic subtype, right-heart volume loading, shunt magnitude, and pulmonary vascular status. Close hemodynamically consequential defects before irreversible pulmonary vascular disease, selecting transcatheter closure only for suitable secundum anatomy and surgery for primum, most sinus venosus, coronary sinus, or associated lesions.Cardiology
Cardiac Amyloidosis
Suspect cardiac amyloidosis in otherwise unexplained increased ventricular wall thickness or restrictive heart failure, then urgently exclude AL disease before using bone-tracer imaging to diagnose ATTR noninvasively. Amyloid typing determines whether immediate plasma-cell therapy or transthyretin-directed treatment is indicated.Cardiology
Coarctation of the Aorta
Coarctation requires lifelong assessment for residual obstruction, hypertension, aneurysm, and associated bicuspid valve disease. Measure arm-leg pressures, define anatomy with cross-sectional imaging, intervene for hemodynamically significant obstruction, and maintain congenital cardiology surveillance after repair.Cardiology
Constrictive Pericarditis
Constrictive pericarditis requires confirmation of ventricular interdependence, separation from restrictive myocardial disease, and classification as inflammatory and potentially reversible versus chronic fibrotic disease requiring pericardiectomy. Multimodality imaging guides the sequence of anti-inflammatory treatment, diuresis, invasive hemodynamics, and surgical referral.Cardiology
Dilated Cardiomyopathy
Dilated cardiomyopathy requires prompt exclusion of ischemia and disproportionate loading conditions, targeted evaluation for reversible or inherited causes, and early HFrEF-directed therapy. Cardiac MRI, family history, genetic testing, and scar assessment refine etiology, recovery potential, and arrhythmic risk.Cardiology
Electrocardiogram
Use the 12-lead electrocardiogram as a time-sensitive diagnostic test for ischemia, rhythm and conduction disorders, then escalate discordant or high-risk findings with targeted monitoring, imaging, electrophysiology, or repeat acquisition.Cardiology and Lipidology
Familial Hypercholesterolemia
Identify probable or definite familial hypercholesterolemia early, confirm etiology when genetic testing will alter family detection or risk assessment, initiate intensive LDL-C lowering, and rapidly distinguish homozygous disease requiring receptor-independent therapy or apheresis from heterozygous disease.Cardiology and Internal Medicine
Hyperlipidemia
Manage hyperlipidemia by separating established ASCVD, severe LDL-C elevation, and risk-based primary prevention; use statins as the foundation, refine borderline decisions with coronary artery calcium, and add nonstatins when LDL-C reduction is inadequate or statins are not tolerated.Cardiology
Mitral Stenosis
Mitral stenosis management hinges on confirming hemodynamic severity, distinguishing rheumatic from calcific anatomy, preventing embolism in atrial fibrillation, and selecting balloon commissurotomy only when rheumatic valve morphology and regurgitation permit durable relief.Cardiology
Mitral Valve Prolapse
Mitral valve prolapse requires management driven by mitral regurgitation burden, left-heart remodeling, symptoms, atrial fibrillation, pulmonary pressure, and a distinct ventricular arrhythmia phenotype rather than leaflet displacement alone.Neonatology, Pediatric Cardiology, Adult Congenital Heart Disease
Patent Ductus Arteriosus
Manage PDA by separating preterm ductal patency from a clinically consequential shunt and from persistent congenital PDA in older patients. Echocardiography establishes anatomy and physiology; treatment is reserved for hemodynamic consequences, with transcatheter closure increasingly favored when definitive intervention is required.Cardiology
Pericarditis
Manage pericarditis by first excluding tamponade and high-risk secondary causes, then confirming active pericardial inflammation, treating uncomplicated inflammatory disease, and escalating recurrent, constrictive, purulent, tuberculous, or malignant phenotypes to targeted imaging, drainage, cause-directed therapy, or expert surgical care.Cardiology
Restrictive Cardiomyopathy
Restrictive cardiomyopathy requires rapid separation from constrictive pericarditis and etiologic classification because amyloidosis, sarcoidosis, iron overload, storage disorders, and endomyocardial disease have divergent confirmatory tests, disease-directed treatments, arrhythmia risks, and transplant implications.Cardiology
Sinus Bradycardia
Manage sinus bradycardia by first identifying hemodynamic compromise, documenting symptom-rhythm correlation, removing reversible causes, and reserving permanent pacing for clinically consequential sinus-node dysfunction rather than an isolated low heart rate.Cardiology
Stable Angina
Evaluate persistent exertional chest symptoms with risk-directed anatomic or functional testing, distinguish flow-limiting obstructive disease from nonobstructive mechanisms, initiate chronic coronary disease risk reduction and antianginal therapy, and reserve invasive angiography with physiologic assessment for actionable anatomy or refractory symptoms.Cardiology
Sudden Cardiac Death
Sudden cardiac death prevention requires rapid identification of arrhythmic substrate, structural heart disease, inherited syndromes, and reversible ischemic triggers, followed by individualized device, disease-directed, and post-shock management rather than reliance on isolated electrocardiographic risk markers.Vascular Medicine
Superficial Thrombophlebitis
Manage superficial venous thrombosis by defining thrombus extent and deep-system proximity with duplex ultrasound, excluding concurrent DVT, and reserving anticoagulation for disease with meaningful risk of extension or embolization.Cardiology
Supraventricular Tachycardia
Manage suspected SVT by first identifying instability and QRS regularity, using vagal maneuvers and adenosine for stable regular narrow-complex rhythms, avoiding inappropriate AV-nodal blockade in pre-excited arrhythmias, and offering electrophysiology study with ablation for recurrent symptomatic disease.Cardiology
Takotsubo Cardiomyopathy
Treat suspected takotsubo cardiomyopathy as acute coronary syndrome until coronary occlusion is excluded, then use ventricular pattern, hemodynamics, and cardiac MRI to distinguish mimics and direct shock management, thrombosis surveillance, and follow-up imaging.Pediatric Cardiology and Adult Congenital Heart Disease
Transposition of the Great Arteries
D-transposition requires rapid confirmation of anatomy, maintenance of effective intracardiac mixing, and neonatal anatomic repair; lifelong surveillance after arterial switch focuses on coronary obstruction, neo-aortic disease, ventricular function, and pulmonary arterial lesions.Cardiology
Tricuspid Regurgitation
Manage tricuspid regurgitation by confirming severity with an integrated echocardiographic assessment, defining primary, atrial-functional, ventricular-functional, or lead-related mechanisms, treating congestion and upstream disease, and referring symptomatic severe disease before advanced right ventricular, renal, or hepatic dysfunction limits procedural benefit.Cardiology and Emergency Medicine
Unstable Angina
Evaluate suspected unstable angina as a troponin-negative ischemic syndrome: obtain prompt ECG and serial high-sensitivity troponin testing, exclude infarction, then use ischemic features and risk stratification to select invasive angiography or noninvasive coronary evaluation.Vascular Medicine
Varicose Veins
Evaluate symptomatic or advanced varicose veins with standing duplex ultrasound to define superficial reflux, obstruction, and deep venous involvement. For intervention-eligible patients with truncal reflux, endovenous ablation generally provides durable anatomic control with less recovery burden than surgery; reserve compression alone for selected circumstances.Vascular Medicine
Venous Insufficiency
Evaluate chronic venous disease with duplex ultrasound for reflux and obstruction, exclude arterial disease before compression, and match treatment to superficial reflux, deep obstruction, edema, skin injury, or active ulceration.Cardiology
Ventricular Septal Defect
Use echocardiography to define ventricular septal defect anatomy and hemodynamic effect, then distinguish patients suitable for observation from those needing congenital heart disease team assessment for surgical or transcatheter closure.Cardiology
Ventricular Tachycardia
Treat sustained wide-complex tachycardia as ventricular tachycardia until a safer alternative is established. Immediate cardioversion is required for instability; stable cases require 12-lead ECG discrimination, antiarrhythmic selection based on ventricular function and substrate, and definitive sudden-death prevention planning.Cardiology and Internal Medicine
Dyslipidemia
Manage dyslipidemia by separating LDL-C–driven ASCVD risk from triglyceride-driven pancreatitis risk, excluding secondary causes, identifying familial disease, and escalating from maximally tolerated statins to evidence-based nonstatins according to residual risk and lipid response.Cardiology and Endocrinology