We All Scream for Calci-YUM! Calcium Channel Blockers

3.1 – “We A Allll Scream for Calci Calci--YU YUM!” M!” Calcium Channel Blockers • Calcium channel blockers (CCBs) target voltage gated L-type calcium channels, the dominant calcium-ion channels in smooth muscle and cardiac muscle (pull on a handle, get some calcium influx) Dihydropyridin Dihydropyridines es (dairy soft serve) • Include nifedipine, nicardipine, amlodipine, clevidipine (dipping station) • Have a greater ratio of vascular smooth muscle effects than cardiac depressant effects (dairy ice-cream on smooth muscle-like tile). Do not appreciably affect AV nodal conduction. • Clinical indications: o Used in chronic treatment of HTN (high pressure pipes). ▪ Cause vasodilation →↓SVR. ▪ Usually given as sustained release with goal of more balanced BP control. o Stable angina (anvil-shaped ice-cream bowl) ▪ β-blockers or nitrates first line; CCBs may be considered with contraindications or reactions, or if HTN not well controlled. ▪ Preferred to non-dihydropyridines because of coronary artery dilation (big red crown). Results in ↓coronary resistance, ↑coronary blood flow, & may enhance development of coronary collaterals. ▪ Cause peripheral vasodilation, ↓afterload, ergo ↓myocardial O2 demand (scale with reduced load) o Treats Prinzmetal angina (coronary vasospasm) (grandmother wearing an anvil medal) o First line treatment for vasospastic disorders which may be associated with Prinzmetal (e.g. Reynaud’s) that has not responded adequately to non-pharmacologic therapy (guy wearing fingerless gloves has cyanotic fingers) o Clevidipine & nicardipine can be administered IV for HTN emergency o Nifedipine used to treat HTN in pregnancy (pregnant woman with knife). Long acting formulations for management; shortacting formulations for emergent treatment of acute HTN. o Nimodipine prevents vasospasm following subarachnoid hemorrhage ▪ MOA unclear. Ideally administered within 4 days. ▪ Subarachnoid hemorrhage most commonly d/t rupture of cerebral hemorrhage (e.g. berry aneurysm, associated with PCOS — “Bubbles in your kidneys, bubbles in the brain”) (brain-shaped ice cream at dipping station with lots of berries on top) • Side effects/toxicities o Contraindicated in HF d/t risk of exacerbation (sad kid with sad balloon) o Hypotension. May → lightheadedness & headaches (collapsed patron in front of dipping station) o Peripheral edema d/t preferential vasodilation of pre-capillary vessels → ↑capillary hydrostatic pressure (collapsed patron with baggy sweatpants) o Reflex tachycardia, especially with more potent fast acting formulations (MD with reflex hammer) o Nifedipine has a relatively high incidence of all adverse effects d/t potency ▪ Also causes exacerbation of myocardial ischemia d/t reflex tachycardia. Contraindicated with unstable angina or MI (heart shaped fruit being cut with huge knife). Large doses increase mortality immediately post-MI. Non-dihydrop Non-dihydropyridines yridines (non (non-dairy) -dairy) • Include Verapamil (Very vanilla) & Diltiazem (delicious Dark Chocolate) • Greater ratio of cardiac effects to vascular smooth muscle effects (non-dairy options on cardiac myocyte like tile). o Verapamil has highest specificity for cardiac tissue. Greatest depressant effect on heart, →↓CO & HR, least vasodilatory effect (very vanilla with small nozzle) o Intermediate effect on both cardiac muscle and has some vasodilatory effects as well (medium-sized nozzle) o Decrease cardiac contractility d/t ↓calcium →↓output (kid cannot pull handle). o Both SA & AV nodal activity may be decreased d/t ↓Calcium (musical notes on non-dairy sign). Can cause bradycardia (dangling watch) • Clinical indications: o HTN control via reduced HR (high-pressure pipes). Usually given as sustained release with goal of more balanced BP control. o Treat stable angina (guy clutching his chest eating from anvil ice cream bowel ▪ β-blockers or nitrates are first line. Dihydropyridines generally preferred. ▪ Non-dihydropyridines ↓O2 demand by acting as a negative inotrope & chronotrope, and ↓systemic BP. o Treat Prinzmetal angina (guy’s shirt has a picture of an anvil on it). o Antiarrhythmic properties especially in SVT o ↓ventricular response to AFib o Verapamil used for migraine prophylaxis (pounding head bell) • Side effects/toxicities o Contraindicated in HF d/t risk of exacerbation (sad kid with sad balloon) o Relatively contraindicated in heart block (V > D) (heart block shield) o Relatively contradicted with β-blockers d/t risk of heart block (heart block shield) o May cause hyperprolactinemia (not pictured, but remember the non-dairies can cause lactation) o Verapamil: causes constipation in 25% patients (janitor walking out of clogged toilet). Also gingival hypertrophy (janitor popping gum)