HY USMLE Review Part I PDF
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This document is a medical review, specifically tailored for the USMLE exam. It includes detailed information on various medical conditions, diagnoses, treatments, and related topics. This document covers topics ranging from common to rare medical conditions.
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MEHLMANMEDICAL HY USMLE REVIEW PART I MEHLMANMEDICAL.COM YouTube @mehlmanmedical Instagram @mehlman_medical MEHLMANMEDICAL.COM 2 MEHLMANMEDICAL.COM HY USMLE Review – Part I Travel +...
MEHLMANMEDICAL HY USMLE REVIEW PART I MEHLMANMEDICAL.COM YouTube @mehlmanmedical Instagram @mehlman_medical MEHLMANMEDICAL.COM 2 MEHLMANMEDICAL.COM HY USMLE Review – Part I Travel + self-limiting watery or brown/green diarrhea à Traveler diarrhea = ETEC HL or HS toxin Bloody diarrhea + poultry consumption à Campylobacter jejuni or Salmonella spp. Abx (clindamycin, beta-lactam, cephalosporin) + diarrhea à C. difficile Dx of C. diff à stool AB toxin test, not stool culture Fever of 104 + abdo distension in C diff à toxic megacolon à laparotomy Tx of C. diff à vancomycin, not metronidazole (updated guidelines as of Feb 2018) Bloody diarrhea + travel à Entamoeba histolytica Tx of E. histolytica à metronidazole + iodoquinol; can give paromomycin Close quarters or military barracks or cruise ship + watery diarrhea à Norwalk virus Child 10 mm with inspiration) à cardiac tamponade or severe asthma Beck triad à hypotension + muffled heart sounds + JVD à pericardial tamponade MEHLMANMEDICAL.COM 3 MEHLMANMEDICAL.COM Tx of tamponade à pericardiocentesis or pericardial window Tamponade à do echo before pericardiocentesis if both listed (even though sounds wrong, on 2CK NBME) Community-acquired pneumonia (CPP) + bilateral CXR infiltrates à Mycoplasma CPP + lobar pattern (right-lower lobe consolidation + dullness to percussion) à Strep pneumo CPP + lobar pattern, but they say “interstitial” in the vignette description à Mycoplasma, not S. pneumo Empiric Tx for CPP à azithromycin Tx for CPP is pt on Abx past three months à fluoroquinolone over azithro Pneumonia in CF patient 10 years à Pseudomonas exceeds S. aureus. Pneumonia after influenza infection à USMLE wants S. aureus Pneumonia + rabbits à F. tularensis Pneumonia + cattle à Coxiella (Q fever) Pneumonia + birds à Chlamydia psittaci Leg swelling + pain + shortness of breath à Pulmonary embolism caused by DVT Tx of PE à Heparin before spiral CT Tx of PE in pregnant woman à V/Q scan, not CT Tx of PE in someone already on warfarin à spiral CT to confirm, then IVC filter Acid-base disturbance in PE à resp. alkalosis (low CO2, high pH, low O2, normal bicarb [too acute to change]) Acid-base disturbance in asthma à resp. alkalosis (low CO2, high pH, low O2, normal bicarb [too acute to change]) Acid-base disturbance in aspirin toxicity first 20 mins à resp. alkalosis (low CO2, high pH, normal O2, normal bicarb [too acute to change]) Acid-base disturbance in aspirin toxicity after 20 mins à mixed metabolic acidosis-respiratory alkalosis (low CO2, low pH, normal O2, low bicarb) Tx for aspirin toxicity à bicarb (increased excretion through urinary alkalinization) Tx for TCA toxicity à sodium bicarb à dissociates drug from myocardial sodium channels Normal calcium à 8.4-10.2 mEq/L Tx of hypercalcemia à 10.2-12 à normal saline (0.9% NaCl) MEHLMANMEDICAL.COM 4 MEHLMANMEDICAL.COM Tx of hypercalcemia à 12-14 à normal saline (0.9% NaCl) only if asymptomatic; add bisphosphonate (e.g., pamidronate) if symptomatic Tx of hypercalcemia à 14+ à normal saline (0.9% NaCl) + bisphosphonate High calcium + polyuria à nephrogenic diabetes insipidus (weird, but on NBME) High calcium + confusion à delirium caused by high calcium Low calcium or potassium not responsive to supplementation à cause is low Mg Low calcium or potassium in alcoholic à hypomagnesemia is cause Ataxia, confusion, ophthalmoplegia à Wernicke encephalopathy (B1 deficiency) Retrograde amnesia + confabulation in alcoholic à Korsakoff psychosis Wernicke-Korsakoff syndrome à mammillary bodies Hx of many pregnancies + downward movement of vesicourethral junction à stress incontinence Tx of stress incontinence à pelvic floor exercises (Kegel); if insufficient à mid-urethral sling Hyperactive detrusor or detrusor instability à urge incontinence Need to run to bathroom when sticking key in a door à urge incontinence Incontinence in multiple sclerosis patient or perimenopausal à urge incontinence Tx of urge incontinence à oxybutynin (muscarinic cholinergic antagonist) or mirabegron (beta-3 agonist) Incontinence + high post-void volume (usually 3-400 in question; normal is 20 à prerenal (hypovolemia) à heart failure BUN/Cr 30k) Dry cough in winter à cough-variant asthma (1/3 of asthmatics only have cough) Young African American woman + dry cough + normal CXR à asthma (activation of mast cells), not sarcoidosis Young African American woman + dry cough + nodularity on CXR à sarcoidosis (noncaseating granulomas) Electrolyte disturbance in sarcoid à hypercalcemia à LOW PTH + high calcium Hypercalcemia in sarcoid, why? à epithelioid (activated) macrophages produce 1-alpha hydroxylase, thereby activating vitamin D3 Increased calcium in sarcoid à means decreased calcium in feces (bc D3 increased small bowel absorption) Tx for sarcoid à steroids Outpatient Tx of asthma à SABA, then low-dose ICS, then maximize dose of ICS, then LABA, then use any number of drugs (e.g., mast cell stabilizers, anti-leukotriene, etc.), then oral steroids last resort Kid with asthma on SABA inhaler + not effective + next best step? à ICS (fluticasone) Kid with asthma on SABA inhaler + most effective way to decrease recurrence? à oral steroids (not next best step, but certainly most effective) 40s male + hematuria + hemoptysis à Goodpasture syndrome Antibodies in Goodpasture à Anti-GBM (anti-collagen IV) Dx of Goodpasture à antibodies first, but confirmatory is renal biopsy showing linear immunofluorescence Hematuria + hemoptysis + “head-itis” (mastoiditis, sinusitis, otitis, nasal septal perforation) à Wegener New name for Wegener à granulomatosis with polyangiitis Dx of Wegener à c-ANCA (anti-PR3; anti-proteinase 3) Asthma + eosinophilia à Churg-Strauss MEHLMANMEDICAL.COM 11 MEHLMANMEDICAL.COM New name for CS à eosinophilic granulomatosis with polyangiitis Dx of CS à p-ANCA (anti-MPO; anti-myeloperoxidase) Hematuria in isolation + p-ANCA in serum à microscopic polyangiitis (MP) Severe renal disease in Wegener or Goodpasture or MP à rapidly progressive glomerulonephritis (crescentic) High ALP + high direct bilirubin + high amylase or lipase à gallstone pancreatitis = choledocholithiasis High ALP + high direct bilirubin + high amylase or lipase + remote Hx of cholecystectomy à sphincter of Oddi dysfunction (can’t be a stone cuz the gallbladder was removed ages ago) High ALP + high direct bilirubin + normal amylase or lipase in someone with recent cholecystectomy à choledocholithiasis (retained stone in cystic duct that descended, but not distal to pancreatic duct entry point) Dx and Tx of choledocholithiasis à ERCP High ALP + high direct bilirubin + normal amylase or lipase in someone with remote cholecystectomy à pancreatic cancer Dx of pancreatic cancer à CT abdo with contrast High ALP + high direct bilirubin + normal amylase or lipase in someone with remote cholecystectomy + CT is negative à cholangiocarcinoma High ALP + high direct bilirubin + normal amylase or lipase + diffuse pruritis + high cholesterol à primary biliary cirrhosis (PBC) High ALP + high direct bilirubin + normal amylase or lipase + autoimmune disease (in pt or family) à PBC Dx of PBC à anti-mitochondrial Abx next best step; liver biopsy is confirmatory Recent cholecystectomy + fever + abdo pain à post-op bile leak High ALP + high direct bilirubin + normal amylase or lipase + CT shows cystic lesion in bile duct à choledochal cyst à do simple excision of cyst (cholangiocarcinoma not cystic + CT can be negative) Imaging to view liver or pancreas à CT with contrast Imaging to view gallbladder à Ultrasound Imaging to view gallbladder in suspected cholecystitis only if USS negative à HIDA scan Imaging to view bile ducts à ERCP or MRCP (choose ERCP > MRCP if both listed) Teenage girl with Hx of cutaneous candida infections since childhood à chronic mucocutaneous candidiasis MCC à answer = T cell dysfunction = impaired cell-mediated immunity on the USMLE Bacterial + fungal + protozoal + viral infections since birth à SCID MEHLMANMEDICAL.COM 12 MEHLMANMEDICAL.COM Bacterial infections since age 6 months à Bruton Bacterial infections only since birth à Bruton (rare as hell to say from birth, but it’s on new 2CK NBME) SCID XR variant à common gamma-chain mutation (IL-2 receptor deficiency) SCID AR variant à adenosine deaminase deficiency Bruton mechanism à tyrosine kinase mutation Hyper IgM syndrome à deficiency of CD40 ligand on T cell (can’t activate CD40 on B cell to induce isotype class switching) Greasy, scaly scalp + itchy + papules + adult à seborrheic dermatitis Tx for SD à azole or selenium shampoo Tx for tinea capitis à oral griseofulvin for patient only How to decrease risk of tinea capitis à avoidance of sharing of hats Tx of onychomycosis (nailbed fungus) à oral terbinafine Tx of tinea pedis à topical terbinafine or topical azole Tx of tinea corporis (ring worm) à topical azole (clotrimazole or miconazole) Tx of cutaneous candida à oral azole Tx of oropharyngeal candida à nystatin mouthwash Tx of esophageal candidiasis à oral azole, not nystatin mouthwash Tx of vaginal candidiasis à topical nystatin before trying oral azole Odynophagia (painful swallowing) in immunocompromised pt à esophageal candidiasis till proven otherwise CNS fungal infection or fungemia (rigors/chills) à amphotericin B Cryptococcal meningitis à amphotericin B + flucytosine, then do fluconazole taper Simple fungal pneumonia à fluconazole Sporothrix schenckii (rose thorn + finger papule) à itraconazole Hypopigmentation on upper back / trunk à tinea versicolor (Malassezia furfur) Tx of tinea versicolor à topical selenium Most common cause of impetigo à S. aureus now exceeds S. pyogenes Tx of impetigo à topical mupirocin Beefy red, well-demarcated skin plaque à erysipelas Most common cause of erysipelas à Group A Strep (S. pyogenes) >>> S. aureus MEHLMANMEDICAL.COM 13 MEHLMANMEDICAL.COM More diffuse pink skin lesion + tenderness + fever à cellulitis Most common cause of cellulitis à S. aureus exceeds S. pyogenes Tx of erysipelas + cellulitis à oral dicloxacillin or oral cephalexin Wide-complex tachyardia à ventricular tachycardia (VT) Narrow-complex tachy à SVT Tx for SVT à vagal/carotid massage first; if doesn’t work, then adenosine Tx of VT à anti-arrhythmics, e.g., amiodarone Tx of SVT or VT in setting of coma / unconsciousness à direct-current countershock Tx of first-degree heartblock or second-degree Mobitz I (Wenckebach) à observe Tx of second-degree Mobitz II or third-degree heartblock à pacemaker First-degree heartblock à PR-interval >200 milliseconds Mobitz I à gradually prolonging PR-interval before a QRS drops Mobitz II à no gradual prolongation of PR-interval; QRS randomly drops Third-degree à HR super slow at 30-40; no relation between p-waves and QRS complexes Infective causes of third-degree à Lyme disease, congenital lupus, diphtheria Give killed IM influenza vaccine when? à Every year in fall/winter only; start from 6 months of age Killed IM Influenza vaccine safe in pregnancy? à Yes, give anytime to pregnant women Live-attenuated intranasal influenza vaccine guidelines? à Only give age 2-49 to non-pregnant, non- immunocompromised persons Vaccines at age 2, 4, 6 months: HepB, Polio Salk, Pneumo PCV13, DPT, HiB, rotavirus (also give HepB at birth) HPV vaccine when à age 9-45 Mom’s HepB status unknownà give neonate HepB vaccine; only give immunoglobulin if mom comes back + MMR à first dose at 12-15 months; second dose age 4-6 years Varicella à one dose between 12-18 months Age 65 or older à give Pneumo PCV13 followed by PPSV23 6-12 months later Asplenia or sickle cell à PCV13 + PPSV23 + HiB + Meningococcal Circular lesion in pancreas seen in pancreatitis à pseudoabscess à answer = ERCP to drain internally Bullous changes on CXR or expanded lungs / hyperlucency à emphysema Centri-acinar emphysema à smokers MEHLMANMEDICAL.COM 14 MEHLMANMEDICAL.COM Pan-acinar emphysema à alpha-1 anti-trypsin deficiency Young adult + non-smoker + has emphysema + relative died of hepatic cirrhosis à alpha-1 anti-trypsin deficiency CREST syndrome lung pathology? à can cause pulmonary fibrosis à pulmonary hypertension Restrictive lung disease à normal or increased FEV1/FVC Obstructive lung disease à decreased FEV1/FVC Why is FEV1/FVC normal or high in restrictive? à radial traction on outside of airways is sticky (keeps airways from closing) Apex to base lung changes when sitting/standing à both ventilation + perfusion increase apex to base Most common cause of otitis media à Strep pneumo Tx of otitis media à oral amoxicillin only Tx of recurrent OM à amoxicillin/clavulanate When to do tympanostomy tube à three or more OM in 6 months, or 4 or more in a year Most common cause of otitis externa à Pseudomonas Tx of otitis externa à topical ciprofloxacin + hydrocortisone drops Prevention of OE in someone with constant water exposure (e.g., crew team) à alcohol-acetic acid drops Tx of earwax buildup à carbamide peroxide drops Low hematocrit + low MCV + low transferrin + low TIBC + transferrin saturation normal or low à anemia of chronic disease Low hematocrit + low MCV + high transferrin + high TIBC + transferrin saturation super-low à iron deficiency anemia Low hematocrit + low MCV + increased red cell distribution width (RDW) à iron deficiency anemia Low hematocrit + low MCV + low/low-normal RDW à thalassemia Low hematocrit + low MCV + low iron + low ferritin à iron deficiency Low hematocrit + low MCV + normal iron + normal or high ferritin à thalassemia Low hematocrit + low MCV + normal iron + normal ferritin in pregnant woman on iron supplements à thalassemia Microcytic anemia that doesn’t improve with iron supplementation à thalassemia Dx of thalassemia à hemoglobin electrophoresis MEHLMANMEDICAL.COM 15 MEHLMANMEDICAL.COM Low hematocrit + normal MCV + low iron + normal or high ferritin à anemia of chronic disease Tx of anemia of chronic disease if renal failure is cause à answer = EPO Tx of anemia of chronic disease if renal failure not cause (IBD, RA, SLE, etc.) à CANNOT give EPO; Tx underlying condition. High BP + smoker + TIA or stroke or retinal artery occlusion. How to best decrease stroke risk à Answer = lisinopril, not smoking cessation Normotensive old pt + TIA or stroke or retinal artery occlusion à atrial fibrillation Hypertensive pt + stroke à do carotid duplex ultrasound Normotensive pt + stroke à do ECG; if ECG normal à Holter monitor High BMI female + irregular menstrual cycles à anovulation Anovulation + hirsutism à PCOS Anovulation. Cause USMLE wants? à insulin resistance à causes abnormal GnRH pulsation Why hirsutism in anovulation à abnormal GnRH pulsation causes high LH/FSH ratio Why high LH/FSH ratio important in anovulation/PCOS à ovulation stimulated when follicle not ready à no ovulation (anovulation) à follicle retained as cyst What’s LH do? à Stimulates theca interna cells (females) and Leydig cells (males) to make androgens What’s FSH do? à Stimulates granulosa cells (females) and Sertoli cells (males) to make aromatase; also primes follicles Tx for PCOS à if high BMI, weight loss first always on USMLE Tx for PCOS if they ask for meds and/or weight loss already tried à OCPs (if not wanting pregnancy); clomiphene (if wanting pregnancy) PCOS increases risk of what à endometrial cancer (unopposed estrogen) Tx of prostate cancer à flutamide + leuprolide together (if they force a sequence, choose F then L). Tx of acute gout à indomethacin (NSAID) first on USMLE; then steroids, then colchicine Tx of acute gout if indomethacin + steroids not listed à colchicine Tx of acute gout in pt with renal insufficiency or Hx of renal transplant à steroids Tx of chronic gout (decrease recurrence) à allopurinol or febuxostat (xanthine oxidase inhibitors) Never give which drug to pt with Hx of uric acid stones or over-producer à probenecid (uricosuric) What are rasburicase / pegloticase à urate oxidase analogues à cleave uric acid directly MEHLMANMEDICAL.COM 16 MEHLMANMEDICAL.COM Young kid + self-mutilation + red-orange crystals in diaper à Lesch-Nyhan syndrome (X-linked) Lesch-Nyhan enzyme à HGPRT deficiency Crystal type in pseudogout à calcium pyrophosphate deposition disease Two main causes of pseudogout à primary hyperparathyroidism + hemochromatosis Two ways pseudogout presents à monoarthritis of large joint (i.e., knee) or osteoarthritis-like presentation in someone with primary hyperparathyroidism or hemochromatosis 32M + dark skin on forearms + increased fasting glucose; Dx? à hemochromatosis (bronze diabetes) Same male + painful hands + x-ray shows DIP involvement. Joint pain Dx? à pseudogout Tx of pseudogout à same as gout acutely; Tx underlying condition for chronic Biggest risk factor for osteoarthritis à obesity Tx of osteoarthritis à weight loss; if normal BMI à acetaminophen before NSAIDs Patient with OA taking naproxen (NSAID) + peripheral edema à increased renal retention of sodium Patient taking NSAID + edema; why? à NSAID decreases renal blood flow à PCT increases Na reabsorption to compensate for perceived low volume status à water follow sodium Tx of rheumatoid arthritis à Two-armed: symptom-relief + disease-modifying anti-rheumatic drugs (DMARDs) Symptom-relief for RA à NSAID first, then steroids (these do symptoms only; do not slow disease progression) DMARDs for early RA à always methotrexate first; if insufficient, add another DMARD (sulfasalazine or leflunomide); if insufficient add anti-TNF-alpha agent Methotrexate MOA à dihydrofolate reductase inhibitor Methotrexate side-effects à pulmonary fibrosis + hepatotoxicity + mouth ulcers (neutropenia) Sulfasalazine MOA à metabolized into sulfapyridine + mesalamine in the gut by bacteria Mesalamine is 5-ASA absorbed as the Tx for RA; only NSAID considered to be DMARD Leflunomide MOA à dihydroorotate dehydrogenase inhibitor (pyrimidine synthesis) Most specific Abs in RA à anti-CCP (cyclic citrullinated peptide), not RF (rheumatoid factor) X-ray of hands in RA vs OA à Only OA has DIPs involved; RA is PIPs + MCPs Symmetry in RA vs OA à RA is symmetrical; OA is not Any pt with red, warm, tender knee à joint aspiration (arthrocentesis); septic arthritis till proven otherwise Biggest risk factor for septic arthritis à abnormal joint architecture Pt groups most likely to get SA à prosthetic joints, RA/OA, recent intense exercise/joint trauma; peds (JRA) MEHLMANMEDICAL.COM 17 MEHLMANMEDICAL.COM Pt group most likely to get SA à those with prosthetic joints (can’t be more abnormal than fake joint) Pt with OA or RA has red, warm, tender knee à do arthrocentesis (septic arthritis) 17F had kickboxing tournament last weekend + knee is red, warm, tender à arthrocentesis (SA) Kid + recurrent knee redness, warmth, pain + fever à Juvenile rheumatoid arthritis (JRA; Still disease) Kid + recurrent joint pain +/- high ESR +/- rash à JRA Kid + recurrent joint pain + anemia à JRA (anemia of chronic disease) Kid with suspected JRA has sore knee à must do arthrocentesis to rule out septic arthritis Most common presentation finding in SLE à arthritis (>90%) Woman 20s-40s + arthritis + thrombocytopenia à SLE Woman 20s-40s + arthritis + mouth ulcer + circular skin lesions à SLE Malar rash + low RBCs + low WBCs + low platelets; mechanism for low cell lines? à increased peripheral destruction (antibodies against hematologic cells lines seen in SLE; isolated thrombocytopenia most common) Tx of SLE flare à steroids SLE + red urine; Dx? à lupus nephritis, more specifically, diffuse proliferative glomerulonephritis (DPGN) Histology of DPGN à wire looping capillary pattern Tx of lupus nephritis à mycophenolate mofetil Tx of discoid lupus à hydroxychloroquine Most specific Abs for SLE à anti-Smith (RNP), not anti-dsDNA Which Abs go up in acute SLE flares à anti-dsDNA (and C3 goes down) Drug-induced lupus Abs à anti-histone Drugs that cause DIL à Mom is HIPP à Minocycline, Hydralazine, INH, Procainamide, Penicillamine Viral infection + all three cell-lines are down à viral-induced aplastic anemia Viral-induced aplastic anemia; next best step in Dx? à bone marrow aspiration Viral-induced aplastic anemia; mechanism? à defective bone marrow production (contrast with SLE) Viral infection + low platelets à ITP (immune thrombocytopenic purpura) Woman 30s-40s with random bruising at different stages of healing à (also ITP; first rule out abuse) Mechanism of ITP à Abs against GpIIb/IIIa on platelets Dx of ITP à answer = low platelet count; don’t choose increased bleeding time ITP Tx à steroids first, then IVIG, then splenectomy MEHLMANMEDICAL.COM 18 MEHLMANMEDICAL.COM ITP episode à next best step in management à steroids ITP episode à most effective way to decrease recurrence à splenectomy (not first-line, but most effective) Family Hx of heme condition treated with splenectomy à hereditary spherocytosis (autosomal dominant) Bleeding time meaning? à platelet problem PT and aPTT meaning? à clotting factor problem Heme findings in ITP à increased BT, normal PT, normal aPTT Heme findings in hemophilia à increased aPTT; bleeding time and PT are normal Cause of hemophilia à X-linked recessive; hemophilia A (factor VIII def); hemophilia B (factor IX def) Tx of hemophilia A à desmopressin for hemophilia A (increases VIII release); then give factor VIII Tx of hemophilia B à give factor IX Classic hemophilia presentation à hemarthrosis in school-age boy; bleeding after circumcision in neonate Inheritance pattern of vWD à AD Heme findings in vWD à bleeding time always high; PT always normal; aPTT elevated half the time What is main function of vWF? à bridges platelet GpIb to underlying collagen (adhesion, not aggregation) What is secondary function of vWF à stabilizes factor VIII in plasma (that’s why aPTT only half time increased) vWD presentation à always one platelet problem + one clotting factor problem Platelet problem? à epistaxis, bruising, petechiae à generally mild and cutaneous Clotting factor problem à menorrhagia, excessive bleeding with tooth extraction, hemarthrosis (but hemarthrosis very very rare in vWD; it is seen in hemophilia) vWD treatment à desmopressin à increases release of vWF Vitamin K deficiency heme parameters? à Increased PT + aPTT; bleeding time normal Cause of vitamin K deficiency in adults à chronic Abx knock out colonic flora Cause of sickle cell à glutamic acid to valine mutation on beta-chain Inheritance of sickle cell à AR Nephrotic syndrome in SS à FSGS Dark urine in SS à renal papillary necrosis HY drugs that cause agranulocytosis à clozapine, ganciclovir, propylthiouracil, methimazole, methotrexate, ticlopidine How will agranulocytosis (neutropenia) present on USMLE? à mouth ulcers + fever MEHLMANMEDICAL.COM 19 MEHLMANMEDICAL.COM Tx for febrile neutropenia / neutropenic fever à immediate broad-spectrum IV Abx Broad-spectrum Abx example? à Pipericillin/tazobactam; cefepime + vancomycin What is ganciclovir used for? à Tx of CMV (DNA polymerase inhibitor) PTU and methimazole are used for what? à Tx of Graves Ticlopidine is what? à ADP2Y12 blocker anti-platelet agent (clopidogrel, prasugrel, ticagrelor also) Strongest indication for anti-coagulation à prosthetic material in heart / prosthetic valve (factoid in isolation) MEHLMANMEDICAL.COM 20 MEHLMANMEDICAL.COM YouTube @mehlmanmedical Instagram @mehlman_medical MEHLMANMEDICAL.COM 21 MEHLMANMEDICAL.COM MEHLMANMEDICAL HY USMLE REVIEW PART I All material is copyrighted and the property of mehlmanmedical. 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