cardiac emergencies. hypertensive emergencies severe hypertension ◦systolic bp > 200 mm hg...

CARDIAC EMERGENCIESCARDIAC EMERGENCIES

Hypertensive EmergenciesHypertensive Emergencies

Severe hypertension◦Systolic BP > 200 mm Hg◦Diastolic BP > 120

If life-threatening organ damage is present, then BP must be reduced quickly to normal

levelsRapid BP reductions can cause strokes, renal

failure, and myocardial ischemiaIf life-threatening organ damage is not

present, reduce the BP gradually to avoid the side effects

PathophysiologyPathophysiology

Most organ damage is from arteriolar necrotizing vasculitis (platelet and fibrin

deposition) and loss of autoregulation of the blood vessels

The most common cause is discontinuation of BP medication

Young patients (<30) or black patients may have secondary causes for HTN, such as

renal disease, endocrine syndromes, drug-induced catecholamine release, or

pregnancy-induced

Clinical Features of HTN-Clinical Features of HTN-induced organ damageinduced organ damage

Encephalopathy◦HA, nausea, vomiting, blurred vision, confusion, seizures,

coma◦stroke

Pulmonary edema◦Due to increased afterload, not fluid overload

Renal impairment◦Decreased glomerular filtration rate, blood/protein in the

urineRetinopathyAortic dissectionAngina/MI

◦Due to increased afterload and decreased perfusionPregnancy related

◦Pre-eclampsia/eclampsia

TreatmentTreatment

With life-threatening organ damage◦Close monitoring◦Sodium nitroprusside (Nipride)

Arteriovenous dilator◦Gylceryl trinitrate

Arteriovenous dilatorEspecially effective when MI/pulm edema co-exist◦Labetalol

An alpha and beta blockerCan exacerbate asthma, heart failure, heart block◦Hydralazine and diazoxide

TreatmentTreatment

Without life-threatening organ damage◦Oral antihypertensives

Sublingual NifedipineBeta blockersACE inhibitorsCalcium channel blockers◦Goal is to reduce the diastolic BP to ~100 mm

Hg by 24-48 hours

Infective EndocarditisInfective Endocarditis

Infection of the heart valves or endocardium

Usually causes a chronic illness but can be acute when due to a virulent organism

Causitive organisms◦Streptococcus viridans: ~50%...poor dentition◦Staphylococcus aureus: 20-25%...IV drug use◦Staphylococcus epidermidis: valve

replacement surgery◦Staphylococcus faecalis:

5%...abortion/genitourinary surgery◦Gram negative organisms: drug addicts/heart

valve replacement◦Fungi: immunosuppressed patient

Infective EndocarditisInfective Endocarditis

Etiology◦Most common in elderly people with

degenerative aortic/mitral valve disease◦Patients with prosthetic valves, rheumatic heart

dx, congenital heart dx◦Abnormal valves are particularly susceptible

following dental or surgical procedures

Infective EndocarditisInfective Endocarditis

Clinical Features◦CNS: embolic infarction, abscesses, meningitis◦General infection: low grade fever, lethargy, malaise,

anemia, wt loss◦Cardiac: murmurs, heart failure, aneurysms◦Late signs: clubbing of digits, splenomegaly◦Joints: arthralgia, septic arthritis◦Skin: vasculitic rash◦Soles of feet: Janeway lesion◦Eyes: retinal hemorrhages◦Mucosal: subconjunctival hemorrhage◦Nail bed: splinter hemorrhages, nailfold infarcts◦Hands: small, red macular lesions, painful swelling of

fingers/toes◦Kidneys: microscopic hematuria, glomerulonephritis◦Embolic infarcts and abscesses: lungs, kidneys, CNS…

loss of peripheral pulses

Infective EndocarditisInfective Endocarditis

Diagnosis◦Mainly clinical◦Confirmed by anemia, raised ESR or CRP,

microscopic hematuria, positive blood cultures, and echocardiography

Management◦ID and treat infection (ATB for ~6 wks)◦Surgery to replace infected prosthetic valves

and native valves if infection/heart failure occurs

Prognosis◦Mortality is ~15%◦Prophylactic ATB used before procedures in

patients with valvular heart disease

Pericardial EmergenciesPericardial Emergencies

Acute pericarditis◦Due to infection (usually viral), MI, uremia,

connective tissue dx, trauma, TB, or neoplasms◦Clinical features: severe positional (sitting

forward relieves) retrosternal chest pain with pericardial rub

◦Diagnosis: concave ST segment elevation…cardiac enzymes may be elevated

◦Management: bed rest, anti-inflammatories, steroids

Pericardial EmergenciesPericardial Emergencies

Pericardial Effusion◦Due to infection, uremia, MI, aortic dissection,

myxedema, neoplasms, radiotherapy◦Clinical features: cardiac tamponade reducing CO, SOB,

pericarditis, venous congestion that increases with inspiration, hypotension with a paradoxical pulse (BP falls

>15 mm Hg during inspiration), distant heart sounds◦Diagnosis: low voltage EKG, CXR shows cardiomegaly,

echocardiography◦Management: pericardial drainage

Constrictive pericarditis◦A progressive fibrotic constriction of the pericardium◦Surgical removal of the pericardium is the only tx