Cardio - Boards Exam

Congenital Heart Defect

CHD occurs in 0.8% of live births → Central Septal Defects most common

• Multifactorial 70%:

  • Empiric CHD Recurrence Risk 3-5% - Decreased with maternal folate intake

• Genetic 25%:

  • Chromosomal and Single Gene

• Environmental/Teratogenic 5%

  • Maternal Alcohol, Diabetes, ***PKU***, 1st trimester fever

    • SSRI → Persistent Pulmonary Hypertension

    • NSAID → Patent Ductos Arteriosus Closure

    • Lithium → Epstein’s Anomaly

Noonan Syndrome: Cardinal Features

Overlap with Turners Syndrome → Can rule out Turners if MALE

Generally NORMAL LIFE EXPECTANCY

• Cardiac

  • ****Pulmonary Valve Stenosis/Dysplasia*****

  • Hypertrophic Cardiomyopathy

• Dysmorphic features

  • Down slanting eyes w/ Ptosis

  • ***Webbed Neck**** → TURNER LIKE

  • ***Shield Chest*** → TURNER LIKE

• Mild ID → can be normal intelligence

• Hematologic:

  • Easy bruising / Excessive bleeding (epistaxis)

• MALES → Cryptorchidism (undescended testicles), bruising fertility, delayed puberty

PRENATAL FINDINGS

• Increased Nuchal Translucency

• Cystic Hygroma

Noonan Syndrome: Etiology

A RASopathy→ Mutation of RAS/MAPK signaling pathway

• PTPN11 50%*** (P.Valve + Short Stature + Bleeding)

• SOS1 10-15%

• RAF1 5-10% (HCM)

• RIT1 5-10% (HCM w/ pre-natal edem/hydrops)

• KRAS <5%

• NRAS rare

Inheritance

• Autosomal Dominant

  • 60% De Novo

  • 40% Inherited

Prenatal Findings (NT or Cystic Hygroma) w/ a NORMAL CHROMSOMAL ANALYSIS → THINK NOONAN SYNDOMRE

CHARGE Syndrome: Clinical Features

Clinical Features is VARIABLE and can be mild to severe and encompass MANY organ systems

Life Expectancy CAN BE DECREASED

• Coloboma: piece of iris missing, pupil too big and misshapen

• Heart Defects: wide variety (70-80%)

  • ToF, VSD, ASD, Aortic Arch, PDA,

• Atresia of the Choanae: back of nasal passage blocked

• Restricted Growth/development:

• Genital Abnormalities: (particularly males) hypogonadism, delayed puberty

• Ear Abnormalities: Hearing loss (Conductive AND Senso-neural), external ear abnormality

  • ****HEARING LOSS****

  • POOR BLANCE (hypoplastic or absent semi-circular canals)

Additional features discovered after gene was identified

• Brain

  • Seizures

  • Abnormalities (Dandy walker, microcephaly,

  • ****Cranial Nerve Abnormalities**** → contributes to hearing loss

• Endocrine Dysfunction

CHARGE Syndrome: Etiology

Gene: CHD7 (important for Neural Crest Cell migration)

Inheritance

• Autosomal Dominant

  • 90% De Novo

  • 10% Inherited

• Can be inherited from a mildy affect parent that didn’t know they had it

Marfan Syndrome: Clinical Features

• ****Aortic Root Dilation****

  • May progress to aneurysm, dissection, rupture → LEADING CAUSE OF DEATH

  • untreated = shortened life expectant

• Eye

  • ***Ectopia Lentis*** → UPWARD DISPLACMENT (vs. downward for Homocysturia)

• Skeletal

  • Tall stature

  • Long, slender fingers

  • Pectus Excavatum / carinatum***

  • Scoliosis

  • Joint hypermobility***

• Pulmonary

  • ****Pneumothorax****

• Spine

  • ***Dura Ectasia*** (weakening or enlarging of membrane around spinal cord)

Treatment

• Echocardiogram 2 times a year

• Beta Blockers + Angiotensin receptor blockers (Losartan) decreased progression of Aortic Wall weakening

Marfan Syndrome: Etiology

Gene: FBN1 (important for connective tissue)

Inheritance

• Autosomal Dominant

  • 75% Inherited

  • 25 De Novo

  • ****PATERNAL AGE EFFECT****

Marfan-Like Syndrome

Conditions that have Marfanoid features PLUS additional signs:

• Loeys-Dietz (TGFBR1 + TGFBR2): Abnormal Palate and DIFFUE aneurysm (throughout the body)

• Homocystinuria (CBS): Mental retardation and High Homocysteine blood levels

• Beals syndrome (FBN2): contracture and crumpled ears

• Multiple Endocrine Neoplasia (MEN) 2A and 2B (RET): Pheocytocytoma and Medullary Thyroid cancer

Ehlers-Danlos Syndromes: Overview

Group of hereditary connective tissue disorder caused by collagen gene mutation and sharing common cardinal features:

• Joint hypermobility: joint flexibility, joint dislocation

• Skin hyperextensibility and fragility: easy bruising, slow healing

• Connective tissue fragility

  • Hernias

  • Valvular hear disease

  • Preterm delivery

  • Bowel dilation/rupture

3 main types

• Hypermobile EDS

• Classical EDS

• Vascular EDS

Elhers Danlos Syndrome - Hypermobile

Gene: NO SINGLE GENE has been identified DESPITE being the most commo form of EDS (80-90% of EDS cases)

Inheritance

• Autosomal dominant

• Variable expressivity

• Diagnosis is made CLINICALLY

Clinical Features

mostly joint flexibility with MINIMAL SKIN FINDINGS

Normal life expectancy

• Musculoskeletal

  • Joint hypermobility - chronic joint pain, dislocations/subluxation

  • Flat feet

• Skin

  • NO SEVERE FRAGILITY

  • mildly stretchy

  • easy bruising (wound healing not affected)

• Other

  • Chronic fatigue

  • GI discomfort (IBS)

  • Autonomic dysfunction (common)

    • Orthostatic intolerance

    • Postural orthostatic tach cardia syndrome (POTS)

Elhers Danlos Syndrome - Classical

Gene: COL5A1, COL5A2 (regulates collagen type V)

Inheritance

• Autosomal Dominant

  • Inherited 50%

  • De Novo 50%

Clinical Features

Skin findings are MUCH more pronounced than hEDS

Life expectancy normal

• Musculoskeletal (less severe than hEDS)

  • Joint hypermobility

  • recurrent dislocations

  • Chronic joint pain

• Skin (way more pronounced than hEDS)

  • EXTREMELY stretchy

  • Fragile

  • ****POOR WOUND HEALING****

  • ****EASY BLEEDING****

  • ****SCARS**** (knees, elbows, forehead, chin)

• Cardiac (not as bad as vEDS)

  • Mild Aortic Root Dilation

  • Mild mitral valve prolapse

• Other

  • Organ prolapse and hernia

Ehlers Danlos Syndrome - Vascular

Gene: COL3A1 (encodes type III collagen)

Inheritance

• Autosomal dominant

  • Inherited 50%

  • De Novo 50%

Clinical features

Mostly artery, intestinal and uterine fragility

Life expectancy REDUCED (vascular dissection/rupture)

• Vascular

  • Arterial aneurysm/ dissection/ rupture (spontaneous)

    • Carotid, Iliac, Mesentric, RENAL, Brain

    • Aorta (NOT AS MUCH AS MARFANS)****

• GI

  • Spontaneous bowel perforation (rupture

• Uterine

  • Pregnancy risk → uterine rupture

• Muscoskeletal

  • mild hypermobility - FINGERS ONLY

• Skin

  • NOT super stretchy (unlike hEDS and cEDS)

  • *****thin/ translucent skin*****

  • Easy bruising

• Face

  • Aged appearance

  • Thin nose, lips

  • narrow face

  • small chin

Management

• No contact sports, working out, unnecessary surgery

• PREGNACY is HIGH RISK

Familial Hypertrophic Cardiomyopathy: Overview

Genes: MYBPC3 (50%), MYH7(40%)

• MYBPC3: later onset, slower progression less severe

• MYH7: earlier onset, greater penetrance for young, more severe

Inheritance

• Autosomal Dominant

  • Inherited 90%

  • De Novo 10%

• ***AGE DEPENDENT PENETRANCE***

  • No symptoms as infant + child

  • Early and Late Adulthood features can emerge

  • Some carriers NEVER show phenotype

Clinical Features

• Left Ventricle Hypertrophy (>15mm wall thickness)

  • Shortness of breath

  • Palpitations

  • Exercise intolerance

  • Passing out (syncope

  • SUDDEN CARDIAC DEATH (can be first manifestation)

• Left ventricular outflow tract obstruction → HEART MURMUR

• Atrial Fibrillation → heart failure and STROKE

Familial Hypertrophic Cardiomyopathy: Recommendations

Diagnosis

• Physical exam → heart murmur check

• Electrocardiogram

  • deep Q waves

  • T-wave inversion

  • ventricular ectopy

• Echocardiogram

Treatments

• Beta blockers (1st line) (slow heart rate)

• Calcium channel blockers (slow heart rate)

• Surgical

  • Implantable Cardioverter-Defibrillator

  • Septal myectomy

  • Alcohol septal ablation

Family Recommendations

• even if testing negative, PERDIOIC CLINCIAL SCREENING still recommended since familial cause of HCM remain unidentified

Syndromic HCM

• Noonan Syndrome

  • as well as other RASopathies

• Pompe Syndrome

• Friedreich’s Ataxia

• Fabray Disease

Familial Dilated Cardiomyopathy: Overview

Gene: TTN (30%), *LMNA* (10%), *MYH7* (5-10%) → many other genes

• LMNA: electrical disease before pump failure → AV block/Sinus node dysfunction BEFORE left-ventricle dysfunction develops → ****MUCH HIGHER RISK OF SCD than TTN****

Inheritance

• Autosomal Dominant

  • Mostly inherited

  • LMNA: 10-30% De Novo Rate

• ***AGE RELATED PENETRANCE***

  • Incomplete Penetrance

Clinical Features

• Dilated Cardiomyopathy

  • Edema

  • Fatigue

  • Shortness of breath (ESCPIALLY LYING FLAT)

  • Exercise intolerance

  • Palpitations

  • Passing out (syncope)

• Heart Failure (progressive reduction of ejection fraction)

• Arrythmias

  • Atrial + ventricular fibrillation

• SUDDEN CARDIAC DEATH

  • ***LMNA ESPECILLAY**

Familial Dilated Cardiomyopathy: Recommendations

Diagnosis

• Physical exam → heart murmur check

• Electrocardiogram

  • nonspecific ST-T abnormalities

  • AV block

  • bundle branch block

  • atrial fibrillation

• Echocardiogram

Treatments

• Beta blockers (1st line) (slow heart rate)

• ACE inhibitors

• Diuretics (edema)

• Surgical

  • Implantable Cardioverter-Defibrillator (ICD) - LMNA requires EARLIER ICD placement

Family Recommendations

• even if testing negative, PERDIOIC CLINCIAL SCREENING still recommended since familial cause of DCM remain unidentified

Syndromic DCM

• Duchene and Becker Muscualr Dystrophy

• Emeery Dreifuss muscular dystrophy

• Hemochromatosis

• Kearns-Sayre Syndrome

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): Overview

Genes: PKP2 (45%), DSP (15%) DSG2 (10%)

• Fibrofatty tissue replaces heart muscle tissue → decreased signal conduction and pumping

• 50-70% of diagnosed patients have an identifiable pathogenic variant

Inheritance

• Autosomal Dominant

  • All inherited → De Novo very rare

• Variable Expressivity***

• Reduced/ Age-dependent Penetrance***

Clinical Features

• Ventricular Arrythmias → start on the right (to lungs) than affects the left (to whole body)

• Exercise Induced Symptoms → exercise stress accelerates process of muscle replaced with fibrofatty tissue***

  • Palpitations

  • Dizziness

  • Passing out (syncope)

• Progressive Heart Failure

• SUDDEN CARDIAC DEATH

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): Recommendations

Diagnosis

• Physical exam → heart murmur check

• Electrocardiogram

  • T-wave inversion

  • Epsilon wave → small deflection at end of QRS complex

• Echocardiogram

• ***Cardiac MRI: can show FATTY REPLACMEENT***

Treatments

• Beta blockers (1st line) (slow heart rate)

• ACE inhibitors

• Surgical

  • Implantable Cardioverter-Defibrillator (ICD)

  • Catheter Ablation

• Lifestyle: Avoid

  • Endurance or competitive sports

  • repeat exercise stress on heart ACCERLATES fibrofatty replacement

Family Recommendations

• even if testing negative, PERDIOIC CLINCIAL SCREENING still recommended since familial cause of DCM remain unidentified

Loeys-Dietz syndrome: Overview

Gene: TGFBR2 (30%), TGFBR1 (20%), SMAD3 (15%), TGFB2 (10%), TGFB3 (5%)

Inheritance

• Autosomal Dominant

  • De Novo 75%

  • Inherited 25%

Clinical Features

• Marfoid Habitus

  • Translucent skin (BUT NOT LAX AS MUCH)

  • Ectopia Lentis ABSENT

• Arterial Dissection

  • Ascending Aorta Dilation/

  • ****ANYWHERE in the Arterial Tree**** (unlike Marfan’s)

    • MUCH more common for childhood dissection (unlike Marfan’s)

    • Dissection occur at SMALLER DIAMETERS tha

• Differentiating Features

  • ***Bifid Uvula****

  • Hypertelorism

  • Craniosynostosis (childhood)

  • Easy Brusing

Loeys-Dietz syndrome: Recommendation

Diagnosis

• Echocardiogram

• CT/ MR Angiography (full arterial tree needs to be viewed)

  • ****Arterial tortuosity**** HALL MARK FINDING

Surveillance

• Life long imaging of Aorta AND ENTIRE ATERIAL TREE

  • FULL BODY MRI

Medical

• Beta blockers

• Angiotensin receptor blockers (losartan)

Familial Thoracic Aortic Aneurysm and Dissection

Gene: ACTA2 (21%), TGFBR2 (5%), MYH11 (5%), MYLK (5%)

• **** MYLK: Aortic Dissection can occur WITHOUT PROGRESSIVE ENLARGMENT (sudden) - may not become dilated before tearing ****

Inheritance

• Autosomal Dominant

  • Mostly inherited

• Reduced/ Age-dependent Penetrance

Clinical Features

Age of Onset Variable

• Aortic Dilation → aortic Dissection/Aneurysm/Rupture→ Death

  • Develops over time

• ISOLATED: no other syndromic features

Diagnosis/Surveillance

• Echocardiogram

• CT/MR Angiography

Treatment

• Betablockers

• Angiotensin blockers

• PREGNANCY: requires high-risk management

Family Screening

• Even if affected person tests negative → FAMILY NEEDS LIFE LONG SURILLANCE

Long QT Syndrome: Overview

Gene: KCNQ1 (35%), KCNH2 (30%), SCN5A (10%)

• KCNQ1 - LQT type I - Exercise induced (***SWIMMING***)

• KCNH2 - LQT type II - Sudden loud noise

• SCN5A (Gain of Function) - LQT type III -**** AT REST or ASLEEP ****

  • 30% of Long-QT patients have no identifiable pathogenic variant

Inheritance

• Autosomal Dominant

  • Inherited 90%

  • De Novo 10%

Clinical Features

• Torsade’s de Pontes: polymorphic ventricular tachycardia

  • Rapid and chaotic contraction of ventricles

  • Cardiac output falls dramatically

  • Causes:

    • Fainting

    • Palpations

    • ***SEIZURES***: inadequate blood flow = loss of consciousness w convulsions

    • ****SUDDEN CARDIAC DEATH****

• Episodes are TRIGGERED

  • KCNQ1 - LQT type I -Emotion or Exercise induced (***SWIMMING***)

  • KCNH2 - LQT type II - Sudden loud noise, emotion, sleep

  • SCN5A - LQT type III -**** AT REST or ASLEEP ***

Long QT Syndrome: Management

Diagnosis

• Electrocardiogram

  • Prolonged QT Interval

Management

• Beta Blocker

Brugada Syndrome: Overview

Gene: SCN5A (cardiac sodium channel protein

• (Loss of function mutation [compared to Gain of function for LQTS)

• 80% of patients do not have identifiable pathogenic variant with current testing

Inheritance

• Autosomal Dominant

  • Mostly inherited

• Variable expressivity

• Reduced/Age-Dependent penetrance

Clinical Features

Structurally NORMAL heart, Arrythmia occurs ***AT REST/ASLEEP***

Age of Onset 30-50yo

• Ventricular Fibrillation → Sudden Cardiac Death

  • Triggers

    • Sleep (Bradycardia)

    • Fever (increases strain on NA+ channels)

Brugada Syndrome: Recomendaitons

Diagnosis

A structurally normal heart, abnormal electrical signals

Electrocardiogram:

• Coved ST elevation: ST segment has a rounded dome, ends in an Inverted T wave

Management

• Lifestyle

  • Aggressively Treat Fevers

  • Avoid medications that block sodium channels + slow heart rate: Local anesthetics, antidepressants,

  • Avoid Alcohol

• Medication

  • Quinidine: an antiarrhythmic that actually helps reduce electrical imbalance

• *****Implantable Cardioverter-Defibrillator****: only treatment proven to prevent SCD

Family Screening

• First-degree relatives should still have clinical evaluation (e.g., ECGs), because genetic testing is not sensitive enough to exclude the diagnosis

Syndromic Long QT Syndrome

• Jervell and Lange-Neilsen Syndrome: Recessive, KCNQ1 or KCNE1, LQT with

  • Congenital Deafness

• Timothy syndrome: Dominant, CACNA1C, LQT with

  • Autism + ID

  • Dental abnormalities

  • Syndactyly

Catecholaminergic polymorphic ventricular tachycardia: Overview

Gene: RYR2 (Cardiac calcium channel protein)

Inheritance

• Autosomal Dominant

  • Inherited 50%

  • De Novo 50%

Clinical Features

Age of Onset 7-12: major cause of Sudden Death in childhood

Excitement/exercise hormones (catecholamines) trigger calcium leakage and overload→ Arrythmia

• Ventricular Tachycardia → palpitations, dizziness, Syncope → Seizure-like episode, Sudden Cardiac death

  • Triggered by EMOTION or EXCERCISE

Catecholaminergic polymorphic ventricular tachycardia: Management

Diagnosis

Structurally normal heart with ***NORMAL RESTING ECG*** (unlike Brugada and Long QT)

• ****Exercise Stress Test****:

  • Bidirectional Ventricular Tachycardia

  • Polymorphic VT

Management

• Lifestyle

  • Avoid competitive sports/strenuous exercise

  • Avoid emotional triggers

• Medication

  • Beta Blockers (Nadolol)

• ICD

  • Only for survivors of cardiac arrest

  • recurrent arrythmia despite medical management

Family Screening

Left ventricular non-compaction cardiomyopathy (LVNC): Overview

Gene: MYH7, TTN, MYBPC3

• Failure of Heart to move from fetal development stage to fully ‘mature heart’

• 20-40% will test positive for pathogenic variant

Inheritance

• Autosomal Dominant

  • Inherited 90%

  • De Novo 10%

• Variable Expressvity

• Age-Depdent Penetrance

Clinical Features

Ventricular wall retains fetal deep ‘tranbulces’ and pockets, causes:

• Poor contraction → reduced ejection fraction → ***Heart failure***

• Electrical instability → V. Arrythmias → ***Sudden cardiac death***

• Blood pooling → Thrombus (clot) formation → ***Stroke / systemic embolism***

Left ventricular non-compaction cardiomyopathy (LVNC): Recomendations

Diagnosis

Heart structure issue → imaging rather than electrical conduction

• Echocardiogram (1st line)

• Cardiac MRI

Treatment

• For Heart Failure:

  • ACE Inhibitor

  • Beta blocker

• For Arrhythmias

  • Antiarrhythmic medication

  • ICD

• For thromboembolism

  • Anticoagulation, but only for documented thrombus (NOT UNIVERSALLY RECOMDMEND FOR ALL PATIENTS WITH LVNC)

Transthyretin amyloidosis: Overview

Gene: TTR (transport protein made in the liver)

• Mutation causes misfolding and aggregation into Amyloid fibrils which accumulate in organs (like lysosomal storage disorders): Heart and Nerves

• Wild-Type ATTR: no pathogenic variant, just occurs with ageing → common in older men (>65yo)

Inheritance

• Autosomal Dominant

  • Mostly hereditary

Clinical Features

Slowly Progressive Disease with Variant specific onset: early onset (30-50s yo) or late onset (50-80s yo)

• Heart → Restrictive Cardiomyopathy → Poor filling

  • Atrial Fibrillation → Sudden cardiac death

  • Heart Failure

• Central nervous system: Peripheral and Autonomic nerves

  • Peripheral: numbness, burning, weakness (starts in feet)

  • Autonomic: hypotension, bowel movement, bladder dysfunction

• Eyes:

  • Virtuous opacites

  • Glaucoma

• Ligaments: ***BILATERAL CARPAL TUNNEL SYNDROME*** (Hallmark sign)

  • Years before cardiomyopathy develops

Transthyretin amyloidosis: Recommendations

Diagnosis

A structural issue that is more easily detected due to the impact on electrical: thick heart but with a low voltage

• Echocardiogram

  • Thickened Ventricle Walls

• Electrocardiogram

  • ***LOW QRS VOLTAGE*** (despite having thick walls)

• Cardiac MRI

  • show amyloid infiltration

Management

• Medication

  • ***Tafamidis***: stabilize the TTR protein so it does not form amyloid plaques

• Gene Silencing Therapies

• Heart failure management

Family Screening

Costello syndrome: Overview

RASopathy

Gene: HRAS (important part of the RAS-MAPK pathway)

• Gain-of-Function → excess cell signaling → abnormal development (congenital heart + cancer predisposition)

Inheritance

• Autosomal Dominant

  • ****De Novo 100%****

• PATERNAL AGE AFFECT

Clinical Features

• Heart

  • ****Multifocal Atrial Tachycardia****

  • Hypertrophic cardiomyopathy

  • Pulmonary Valve stenosis

• Cancer: overall lifetime risk 10-15%

  • ***Rhabdomyosarcoma*** (NON-CARDIAC muscle tumor)

  • Neuroblastoma

  • Transitional Cell Carcinoma (Kidney)

• Face: Coarse features

• Skin:

  • ***Papillomas***

  • Loose

  • Hyperpigmentation

• Developmental

  • Hypotonia

  • Mild/Moderate ID

Cardio-Facio-Cutaneous (CFC) Syndrome

RASopathy

Gene: BRAF (75%), KRAS, MAP2K1, MAP2K2

Inheritance

• Autosomal Dominant

  • ***ALWAY DENOVO***

Clinical Features

• Heart

  • ***Pulmonary Valve stenosis***

  • Hypertrophic cardiomyopathy

• Face

  • down slanting palpebral fissures

  • short nose

  • low-set ears

• Skin

  • Sparse, curly hair (absent eyebrows)

  • Eczema

  • ***Dry Skin***

  • Hyperkeratosis

• Development

  • Hypotonia

  • Severe Intellectual disability

LEOPARD Syndrome (Noonan Syndrome with Multiple Lentigines): Overview

RASopathy

Gene: PTPN11

Inheritance

• Autosomal Dominant

  • ***Inherited 50%***

  • De Novo 50%

Clinical Features

“LEOPARD” Acronym - Same features as Noonan w Lentigines

• ****Lentigines****: hundreds/thousands of small dark freckles → 4-5yo increase with age

• ECG Abnormalities

• Ocular Hypertelorism

• Pulmonary Stenosis: less common than Noonan

  • ****HYPERTROPHIC CARDIOMYOPATHY*****

• Abnormal Genitalia

• Retarded growth: Short stature

• ***Deafness***: Sensorineural*****

Normal Intelligence

Holt-Oram Syndrome: Overview

Gene: TBX5 (regulates upper limb and cardiac septation/conduction development)

• Severity is HIGHLY VARIABLE

Inheritance

• Autosomal Dominant

  • De Novo 50%

  • Inherited 50%

• Variable Expressivity

Clinical Features

• Upper Limb: Hand

  • Fused/malformed Carpal (wrist) bones

  • Hypoplastic/absent thumb

• Heart (

  • ***Conduction Defect*** (wide range and can present with out heart defect)

    • First-degree AV block: impulse gets carried SLOWER than usual

    • Progressive AV Block: impulse gets slower and slower overtime

  • Atrial Septal Defect → ****SECUNDUM ASD****

  • Ventricular Septal Defect

Hereditary hemorrhagic telangiectasia

Gene: ENG (50%), ACVRL (45%), SMAD4 (5%)

• SMAD4: also causes ***Juvenile Polyposis Syndrome***

Inheritance

• Autosomal Dominant

  • Inherited 90%

  • De Novo 10%

Clinical Features

• Arteriovenous Malformations (AVM): arteries empty right back into veins, forma tangled mess that by-passes small capillaries)

  • Lungs: clots aren’t filtered out → Ischemic stroke

  • Brain: hemorrhage, seizure, stroke - usually asymptomatic until found via screening

  • Liver

  • GI

• ***Telangiectasia***: when an AVM occurs near the skin surface, they are red and visible

• Recurrent Epistaxis: recurrent nosebleeds, progressively more with age