Afternoon Delight

Afternoon Delight PathoPhysiology Review July 29th, 2010

Call from ED… • A 60-year-old man is coming in with chest pain

Additional History • Dull substernal chest pressure for 1 hour with diaphoresis, mild nausea, palpitations, and dyspnea. • Denies prior history of similar chest pain, reflux, or heart failure symptoms. • PMH: DM, HTN • PSH: none • MEDs: Glipizide and HCTZ • ALL: none • SH: 15 pack year smoking history • FH: none

Physical Exam T 37 ◦C BP 154/88(equal in both arms) HR 95 RR 20, 99%RA GEN:A+Ox3, mild distress HEENT: normal CV: RRR, normal heart sounds, grade 1/6 early systolic murmur at the upper left sternal border. No JVD PULM: CTAB ABD: soft NT, ND, +BS EXT: no edema

EKG

Initial Management?

What Happened? Symptoms Discharge Diagnosis Medications Intervention

Why? Symptoms Discharge Diagnosis Medications Intervention

Angina occurs whenever myocardial oxygen demand exceeds supply Symptoms Demand Supply • O2 carrying capacity • PaO2 tension • Hemoglobin • O2 extraction • Coronary blood flow • Heart Rate • Systolic Blood pressure • Wall Tension • LVEDP/Preload • Wall thickness • Contractility 6:45 am

Symptoms Demand o • Heart Rate • Systolic Blood pressure • Wall Tension • LVEDP/Preload • Wall thickness • Contractility 6:45 am Dis Mon 2008;54:671-689

Symptoms Supply • O2 carrying capacity • PaO2 tension • Hemoglobin • Oxygen Extraction • Coronary blood flow 6:45 am • Atherosclerosis Oxygen content = (SaO2 x Hb x 1.34) + .003(PaO2) Coronary perfusion pressure = pressure gradient between the right atrial diastolic pressure and the aortic diastole pressure. Dis Mon 2008;54:671-689

Symptoms • Oxygen extraction in the coronary circulation is almost maximal at rest. • The only significant mechanism available to the heart to increase oxygen consumption is to increase perfusion • In patients with progressive atherosclerotic narrowing of the epicardial vessels, an ischemic threshold occurs, and exercise beyond this threshold can produce: • abnormalities in diastolic and systolic ventricular function • electrocardiographic changes • chest pain 6:45 am

STEMIs are caused by acute plaque rupture Symptoms 6:45 am N Engl J Med 2005;352:1685-95.

Diagnosis LCX 7:45 am

Diagnosis 7:45 am N Engl J Med 2003;348:933-40.

Diagnosis 7:45 am

Morphine • Oxygen • Nitrates • Aspirin • Beta-Blocker • Statin • Heparin/Lovenox Medications 8:05 am

Angina occurs whenever myocardial oxygen demand exceeds supply Medications Demand Supply Morphine Oxygen • O2 carrying capacity • PaO2 tension • Hemoglobin • O2 extraction • Coronary blood flow • Heart Rate • Systolic Blood pressure • Wall Tension • LVEDP/Preload • Wall thickness • Contractility Nitrates βBlocker 8:05 am

Medications Statins Aspirin Heparin 8:05 am

Primary PCI • lower short-term mortality rates • less nonfatal reinfarction • less hemorrhagic stroke than those treated by fibrinolysis • Door to Balloon Time • Mortality increases significantly with each 15-minute delay in the time between arrival and restoration of TIMI-3 flow (door to– TIMI-3 flow time) Intervention 9:10 am

Intervention • Early clopidogrel may reduce CV death at 30days 9:10 am PeriproceduralGPIIb/IIIa improves CV outcomes Reduces risk of reinfarction

What meds to send home with? • Beta-blocker • Mortality benefit • Primary prevention of ventricular arrythmias • Aspirin • Clopidogrel • Statin • Ace-inhibitor • Should be given in first 24 hours of STEMI in setting of pulmonary congestion, anterior MI, EF<40% • +/- Aldosterone blocker • EPHESUS trial: for pts with EF<40%, HF, or diabetes on a stable regimen of beta-blocker and ACEi Discharge HD #5 Antman et al. Management of Patients With STEMI: Executive Summary JACC Vol. 44, No. 3, 2004 :671–719.

Discharge HD #5 n engl j med 360 (21) 2009: 2237-40.

Afternoon Delight