Nursing Field Notes / Cardio · Pathophysiology Course
Endocarditis 🦠
Infective & noninfective inflammation of the heart's INNER lining & valves
NG-229CARDIOADHD-friendly visual edition
Inflammation INside the heart — bacteria (or, less often, sterile clot/inflammation with no bacteria) seed the endocardium and valves, growing a vegetation that keeps valves from closing fully. Less cardiac output = less oxygen OUT to the body, plus pieces of that vegetation can break off and embolize to the brain, lungs, and fingertips.
🦷 Protect the at-risk valveAntibiotic prophylaxis before dental/procedures; gentle oral care, no flossing.
🧨
CAUSE
STEP 1 · BUGS FIND A DOOR
A valve gets damaged or exposed, bacteria land on it, and a vegetation grows — the whole disease follows from that one event.
🫀 A heart valve with vegetation growth
EXAM TIP Infective endocarditis = bacteria seed a valve (often one already scarred or abnormal), forming a sticky vegetation of fibrin, platelets, and bacteria. The leaflets can't close fully → regurgitation → the vegetation keeps growing and keeps shedding infected emboli.
🧠 "Mold on the valve." Picture the vegetation exactly like fuzzy mold growing on a screen door — the door (valve) can't shut all the way anymore, and little bits of mold keep breaking off and traveling.
⚠️ Causes — how bacteria get in
💉 Dirty needles — IV drug use
🦷 Dental visits without antibiotic prophylaxis in an at-risk client
🔪 Heart surgery — valve replacement & CABG
🤒 Untreated strep throat
🧠 "Four doors bacteria walk through." Needles, teeth, surgery, and an ignored strep infection — every route is a break in a barrier that lets bacteria reach the bloodstream and then the valve.
🔤 Infective vs noninfective
🦠 Infective
🧊 Noninfective
Bacteria present — "mold on the valve"
No bacteria — sterile inflammation/clot only
Needs antibiotics
Treat the underlying cause (e.g., lupus, cancer)
🧠 Say the word: Endo (inside) + card (heart) + itis (inflammation) = inflammation INSIDE the heart — the lining & valves, not the sac around it (that's pericarditis, NG-066) and not just the muscle (myocarditis).
🔎
CLUES
STEP 2 · SPOT IT
One mnemonic for the systemic picture, four unmistakable fingertip-and-eye findings, and the culture rule that changes the whole plan.
🔤 Signs & symptoms — "CLOT"
C — Clots in the heart & brain — risk for stroke/CVA; monitor for agitation, change in level of consciousness
L — Lung fluid — crackles
O — Overheated — fever
T — Too little oxygen — low cardiac output
Plus: clubbing fingers, new or changing heart murmur, fatigue, and the four classic peripheral findings below.
🧠 A CLOT is exactly what's forming — on the valve, and sometimes flying to the brain. The mnemonic is the pathophysiology.
🖐️ The four classic exam findings — each one is visually distinct
Painless flat macules on palms/soles — from septic microemboli.
🩸 Splinter hemorrhages
Thin red-brown lines under the nail bed — tiny clots (microemboli).
👁️ Roth spots
Retinal hemorrhages with a pale white center — seen on fundoscopic exam.
🧠 "Osler = Ouch, Janeway = No way (no pain)." Both are red/purple skin lesions from the same immune/embolic process — the ONE thing that tells them apart on an exam is pain. Splinters live under the nail; Roth spots live in the eye.
🧪 Diagnostics: cultures BEFORE antibiotics
Draw blood cultures from multiple sites before the first dose of antibiotics. Giving antibiotics first can sterilize the blood and make it impossible to identify the organism — which is exactly what guides therapy.
🩸 Multiple sets, different venipuncture sites, before treatment starts
🫀 Echocardiogram — visualizes the vegetation directly
🧫 Elevated WBC, inflammatory markers
🧠 "Culture first, cure second." If a question shows antibiotics being hung before cultures are drawn, that's the error to catch.
🚨 Watch for embolic stroke
Pieces of the vegetation can break off and travel to the brain. New agitation or a change in level of consciousness in an endocarditis client is a stroke until ruled out.
🧠 The C in CLOT is not abstract — it's a real embolus that can lodge in the brain within minutes.
🩺
CARE
STEP 3 · CLEAR THE INFECTION, PROTECT THE VALVE
Antibiotics do the heavy lifting; teaching and prophylaxis keep it from happening again.
💊 Treatment
💉 IV antibiotics — organism-specific, typically a prolonged course; started only after cultures are drawn
🔪 Valve repair or replacement for severe damage, large/embolizing vegetations, or heart failure from valve destruction
🧠 "Bugs out, then rebuild." Kill the infection first — surgery on an actively infected valve is reserved for those who need it urgently (large vegetations, heart failure, uncontrolled infection).
🦷 Oral care — brush, don't floss
🪥 Brush 2x/day with a soft toothbrush
NO flossing — can introduce bacteria into the bloodstream
🦷 Routine dental care is still important — just done with antibiotic prophylaxis, not skipped
🧠 "Brush soft, skip the string." Any break in the gum line is a door bacteria can walk through straight to a damaged valve.
🦷 Dental & procedure prophylaxis for at-risk clients
Clients with a history of endocarditis, a prosthetic heart valve, certain congenital heart disease, or a cardiac transplant with valve regurgitation need prophylactic antibiotics before dental work or other procedures that can cause bacteremia.
📣 Tell every provider — dentist, surgeon, even routine procedures — about the history of endocarditis
🪪 Consider a medical alert card/bracelet
🧠 "Announce it before they touch you." The single biggest prevention failure is the client not mentioning their history — make that the habit you teach.
✅ Nursing interventions summary
1
🩸 Cultures before antibiotics — never reverse the order
2
🧠 Monitor — new agitation or altered LOC = possible embolic stroke
3
📣 Let all providers know of history of endocarditis
4
🦷 Dental visits/surgery in an at-risk client require prophylaxis
5
💊 Antibiotic adherence — the full prolonged course, every dose
🧠 "CLOT" gets you the signs; this ladder gets you the actions. Say both out loud and you have the whole page.
⚡
QUICK RECALL
SAY IT OUT LOUD
🦠 Vegetation on the valveFibrin + platelets + bacteria stop the leaflets from closing
🩸 Cultures BEFORE antibioticsNever sterilize the sample before you identify the bug
🖐️ Osler = ouch, Janeway = no waySplinters under nails, Roth spots in the eye
🦷 Prophylax the at-risk valveProsthetic valve or prior endocarditis + dental work = antibiotics first
🎯 Cover & check — 4 rapid-fire questions
Q1: What must happen before the first dose of antibiotics is given?
Blood cultures — multiple sets from different sites — must be drawn first, or the organism may never be identified.
Q2: How do you tell Osler nodes apart from Janeway lesions?
Osler nodes are painful/tender nodules on the finger or toe pads. Janeway lesions are painless flat macules on the palms or soles.
Q3: What does the CLOT mnemonic stand for?
Clots in the heart & brain (stroke risk) · Lung fluid (crackles) · Overheated (fever) · Too little oxygen (low cardiac output).
Q4: Which clients need antibiotic prophylaxis before dental visits or procedures?
Those with a history of endocarditis, a prosthetic heart valve, certain congenital heart disease, or a cardiac transplant with valve regurgitation — and they should tell every provider about that history.