NSG 1540 Week 6: Cardiovascular Physiology & Pharmacology

Comprehensive vocabulary flashcards covering cardiovascular anatomy, physiology, the RAAS mechanism, hypertension classifications, and various drug classes including diuretics and antihypertensives.

Automaticity

The ability of cardiac cells to generate an action potential without external stimuli.

Conductivity

The ability of the heart to rapidly conduct electrical impulses.

Myocardium

The heart muscle layer.

Sarcomere

The functional unit of a muscle cell.

Septum

A partition separating the right and left sides of the heart.

Diastole

The resting phase where heart muscle relaxes and chambers fill with blood.

Systole

The contracting phase where blood is pumped out of the heart.

Starling’s Law of the Heart

States that the more the heart muscle is stretched by incoming blood, the stronger the subsequent contraction will be.

Syncytia

Fibers that allow the myocardium to contract synchronously.

P wave

Represents atrial depolarization (impulse through atrial tissues) on an ECG.

QRS complex

Represents ventricular depolarization on an ECG.

T wave

Represents ventricular repolarization on an ECG.

SA Node

The pacemaker of the heart where electrical impulses originate.

Sinus Tachycardia

A sinus arrhythmia where the heart rate exceeds $100$ beats/min.

Ventricular Fibrillation

A potentially fatal arrhythmia due to a lack of coordinated pumping originating below the AV node.

Preload

The volume of blood returned to the heart to be pumped.

Afterload

The resistance against which the heart must pump, measured by blood pressure.

Contractility

The force of the contraction, which is increased by calcium influx.

Renin

An enzyme released from juxtaglomerular cells in response to low blood pressure or poor oxygenation of the nephron.

Angiotensin II

A potent vasoconstrictor that stimulates the release of aldosterone and antidiuretic hormone (ADH).

Aldosterone

A hormone that causes the kidneys to retain sodium and water, increasing blood volume.

Baroreceptors

Specialized pressure and stretch-sensitive receptors in the aortic arch and carotid arteries that regulate blood pressure moment-to-moment.

Stroke Volume

The amount of blood pumped with each heart beat.

Total Peripheral Resistance

The resistance of the muscular arteries (especially small arterioles) to the blood being pumped through them.

Stage 1 Hypertension

A blood pressure range of $130-139/80-89\,mm\,Hg$.

Stage 2 Hypertension

A blood pressure measurement of $\ge 140/\ge 90\,mm\,Hg$.

Hydrochlorothiazide

A thiazide diuretic prototype indicated for first-line management of hypertension that works in the early distal convoluted tubule.

Angioedema

A serious adverse effect of ACE inhibitors involving facial swelling, stinging, or itching of the mouth or throat.

Captopril

An ACE inhibitor prototype used for hypertension and heart failure that may cause a dry persistent cough.

Losartan

An Angiotensin II Receptor Blocker (ARB) prototype used for hypertension and stroke prevention.

Aliskiren

A direct renin inhibitor prototype that treats hypertension by inhibiting the production of Angiotensin I.

Calcium Channel Blockers (CCB)

A drug class (e.g., nifedipine, diltiazem) that blocks calcium movement to promote arterial vasodilation and suppress SA/AV node conduction.

Metoprolol

A cardioselective (beta-1) blocker used for hypertension and heart failure; pulse should be held if $<50$ bpm.

Propranolol

A nonselective beta blocker that can cause bronchoconstriction and mask signs of hypoglycemia.

Carvedilol

A mixed alpha and beta blocker used for hypertension and as an adjunct for heart failure.

Nitroprusside

A vasodilator prototype used for hypertensive crises; carries a risk of cyanide poisoning or thiocyanate toxicity.

Furosemide (Lasix)

A high-ceiling loop diuretic that works in the ascending limb of the loop of Henle and can cause ototoxicity.

Spironolactone (Aldactone)

A potassium-sparing diuretic and aldosterone antagonist used to treat hypertension and hypokalemia.

Mannitol (Osmitrol)

An osmotic diuretic used to reduce intracranial pressure (ICP) and intraocular pressure (IOP).

Isotonic Solution

A solution with equal osmolarity as the blood (e.g., $0.9\%\,Normal\,Saline$), resulting in no fluid movement across cell membranes.

Hypotonic Solution

A solution with lower osmolarity than blood (e.g., $0.45\%\,Saline$) that causes water to move from the extracellular compartment to the intracellular compartment.

Hypertonic Solution

A solution with higher osmolarity than blood (e.g., $3\%\,Saline$) that causes water to move from the intracellular compartment to the extracellular compartment.

Colloids

Plasma volume expanders like albumin that increase colloid oncotic pressure to pull fluid into the blood vessels.

Normal Sodium (Na) level

$$135-145$$

Normal Potassium (K) level

$$3.5-5.0$$

Magnesium Toxicity Antidote

Calcium gluconate IV