Year: 2026

Hemodynamics is the study of how blood flows through the heart and blood vessels. It is a core physiology concept, not a single disease, test, or medication. In cardiology, Hemodynamics is discussed when interpreting blood pressure, cardiac output, valve disease, and heart failure. It is encountered in bedside assessment, echocardiography, cardiac catheterization, and critical care monitoring.

Contractility is the heart muscle’s intrinsic ability to generate force and shorten during systole. It is a core physiology concept (a functional property), not a symptom or a diagnosis by itself. It is commonly discussed when interpreting heart failure, shock, echocardiograms, and hemodynamics. It helps explain why two patients with similar blood pressure or ejection fraction can have different cardiac performance.

Afterload is the mechanical “load” the ventricle must work against to eject blood during systole. It is a physiology concept (not a symptom, test, or diagnosis) used to explain cardiac performance. In cardiology, Afterload most often comes up when interpreting heart failure, hypertension, and valvular disease. It is also used when discussing hemodynamics in critical care, echocardiography, and pressure–volume loops.

Preload is a hemodynamic concept that describes how much the heart muscle is stretched before it contracts. It is a physiology term rather than a disease, test, or medication. In cardiology, Preload is most often discussed in heart failure, shock, and critical care fluid management. It helps connect bedside findings to cardiac output and congestion.

Cardiac Index is a hemodynamic measurement that describes cardiac output adjusted for body size. It is a physiologic parameter (not a symptom or diagnosis) used to estimate how effectively the heart delivers blood relative to the patient’s body surface area. It is commonly encountered in intensive care, the cardiac catheterization lab, perioperative monitoring, and advanced heart failure care. It helps clinicians interpret “how much flow” is present in context, rather than relying on cardiac output alone.

Ejection Fraction is a measurement of how much blood a ventricle pumps out with each heartbeat. It is a cardiac imaging and physiology metric, not a symptom or a diagnosis by itself. It is most often reported for the left ventricle and commonly appears on echocardiograms and cardiac magnetic resonance reports. It is used frequently in heart failure, cardiomyopathy, valvular disease, and post–myocardial infarction assessments.

Stroke Volume is the amount of blood the heart ejects from a ventricle with each beat. It is a physiologic measurement and a core hemodynamic parameter. It is commonly discussed in echocardiography, cardiac catheterization, and critical care monitoring. It helps connect basic cardiac physiology to clinical decision-making in cardiology.

Cardiac Output is the amount of blood the heart pumps into the circulation each minute. It is a physiologic measurement, not a disease or a symptom. It is commonly discussed in heart failure, shock, valvular disease, and critical care cardiology. It connects bedside findings to hemodynamics and organ perfusion.

Coronary Calcium Score is a **score** derived from a specialized computed tomography (CT) scan of the heart. It estimates the amount of **calcified atherosclerotic plaque** in the coronary arteries. It is commonly encountered in cardiology as a tool for **cardiovascular risk assessment** and prevention planning. It is most often discussed in outpatient settings for people without known coronary artery disease.

A CT Coronary Angiogram is a computed tomography (CT) imaging test that visualizes the coronary arteries. It is a diagnostic test used to evaluate coronary artery disease and related coronary anatomy. It is commonly encountered in chest pain evaluation, preventive cardiology discussions, and pre-procedural planning. It uses X-rays, ECG (electrocardiogram) synchronization, and usually iodinated contrast to create detailed images.