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Key Terms

afterload
the amount of force the left ventricle must push against
angiotensin I
a protein in blood that promotes aldosterone secretion and raises blood pressure
angiotensin II
a protein in the blood that causes the muscular walls of the arterioles to constrict and narrow, thereby increasing blood pressure
angiotensin II receptor blocker (ARB)
a classification of drugs that bind to and inhibit angiotensin II type I receptors
angiotensin receptor/neprilysin inhibitor (ARNI)
a classification of drugs that bind to and inhibit angiotensin II type I receptors and inhibit the breakdown of BNP
angiotensin-converting enzyme (ACE) inhibitor
a classification of drugs that block the body’s production of angiotensin II; causes vasoconstriction and inhibits the reuptake of norepinephrine, which stimulates catecholamine release
beta-adrenergic blocker
a classification of drugs that inhibit chronotropic, inotropic, and vasoconstrictor response to catecholamine, epinephrine, and norepinephrine by exerting effects on adrenergic receptors beta 1, beta 2, and alpha
cardiac glycoside
a classification of drugs that decrease heart rate and increase cardiac contraction by blocking the sodium-potassium ATPase pump
cardiac output
the product of the heart rate and stroke volume, or the amount of blood ejected with each heartbeat in a given period of time
contractility
the ability of the ventricle to squeeze or pump blood
diuretic
a classification of drugs that induce sodium loss and increase urine flow; typically used to treat hypertension, heart failure, and volume overload states
ejection fraction
the fraction of blood that is pumped out of the heart with each beat
heart failure
a clinical syndrome that occurs when the heart does not generate adequate cardiac output
heart failure with preserved ejection fraction (HFpEF)
occurs when the fraction of blood ejected by the left ventricle has not changed but cardiac output is inadequate; often due to stiffness of the ventricular muscle
heart failure with reduced ejection fraction (HFrEF)
occurs when the fraction of blood ejected by the left ventricle is actually reduced; often due to damage to the left ventricular muscle through long-standing hypertension or coronary artery disease
heart rate
the number of times each minute the heart beats
If current inhibitor
a classification of drugs that inhibit cardiac pacemaker current (If), which causes lowered heart rate
ivabradine
medication used in heart failure that regulates heart rate and causes increased diastolic filling time, which results in increased cardiac output
mineralocorticoid receptor antagonist (MRA)
a classification of drugs that cause diuresis and other effects by binding to receptors in the nephron so that aldosterone is not able to affect it and cause sodium and water reabsorption
preload
the volume of blood returning to the heart
renin-angiotensin-aldosterone system (RAAS)
a compensatory mechanism the body activates during hypotension (when the blood pressure is low)
sodium-glucose cotransport inhibitor (SGLT2I)
a classification of drugs that cause diuresis and other benefits that block the reabsorption of sodium and glucose in the proximal tubule of the nephron
stroke volume
the volume of blood pumped out of the left ventricle of the heart during each systolic cardiac contraction
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