Adult Cardiac

Cardiac Anatomy

  • Vasculature

    RCA Supplies :

    • RA

    • Most of RV

    • SA & AV nodes

    LCA, LAD and L circ Supplies :

    • LV

    • Can have left dominant circulation to AV node

    *image from wikipedia

  • Cadaveric Anatomy

    *image from University of Minnesota

  • A/P view

    *image from physiopedia.com

Cardiac Surgical Information

 

Coronary artery disease is the most common cause of death in the U.S

Most atherosclerotic disease is proximal

  • RF: HTN, smoking, DM, HLD, male gender

  • TX: lifestyle changes, aspirin, statin, stenting, CABG

MI complications:

  • Ventricular septal wall rupture -> hypotension, pansystolic murmur

    • intra-aortic balloon pump; patch

  • papillary muscle rupture -> mitral regurgitation

    • intra-aortic balloon pump; valve replacement

Stenting:

Drug eluting stents- everolimus/zotarolimus/ridaforolimus

***drug eluting stents have significantly better patency rates, and their safety profile is equal to/better than bare-metal stents

***try to use drug eluting stents when possible. Some contraindications include: large vessel size (>5mm), can’t take dual anti-platelet

Coronary Artery Bypass Graft (CABG):

  • Indications

    • 70% stenosis for most areas; >50% for LAD

    • 2 vessel disease if involves LAD

    • 3 vessel disease

    • Can’t be stented

  • IMA (95% patency), Saphenous (80% patency)

  • RF for complications: pre-op cardiogenic shock, emergent operation, low EF, older age

image courtesy of brown.edu

  • image courtesy of brown.edu

 

  • The coronary veins have the lowest oxygen concentration in the body(appx 30%)

  • The RIGHT ventricle is the most injured in both blunt and penetrating trauma

  • The RIGHT atrium is a low pressure system, and collapses with tension pneumothorax or cardiac tamponade

Valvular Disease

Aortic Stenosis is the most common valvular lesion

  • could be from aging/degeneration, congenital issue (bicuspid) or rheumatic heart disease

  • Surgical indications:

    • aortic valve area of <1cm (normal is 2-3cm)

    • pressure gradient >50mm Hg (normal is none)

    • symptomatic- syncope (worst), angina, CHF

Mitral Regurgitation

  • causes LEFT ventricular enlargement

  • can cause A fib, pulmonary congestion

Mitral Stenosis

  • causes pulmonary edema/dyspnea

  • can try balloon valvuloplasty

Hirji et al. Study looking at 643 patients showed NO mid-long term survival difference between mechanical or bioprosthetic valves

Hirji et al. Study looking at 643 patients showed NO mid-long term survival difference between mechanical or bioprosthetic valves

 
 
as presented by Dr. Mathew, Dr. Patel, and Dr. Low. July 2019.

as presented by Dr. Mathew, Dr. Patel, and Dr. Low. July 2019.

Three complications to watch out for:

 

Mediastinitis

0.4-5% (avg 1-2%)

RF: DM, obesity, PAD, smoking, prior cardiac surgery, mobilization of IMA, surg >5hrs, emergent srugery

Typically single organism (staph aureus)

Sepsis, chest pain, signs of wound infection

CT- mediastinal fluid, pneumomediastinum

TX: debridement (typically NO need for total sternotomy) +/- vac/pec flap; broad spectrum ABX (2-6 weeks)

Risk from flaps- dehiscence, necrosis, recurrent infection, hematoma

Post-Pericardiotomy Syndrome

  • fever, chest pain, SOB, friction rub

  • Diffuse ST changes

TX: NSAIDs, steroids

Bleeding

  • >500cc in first hour; or >250cc/hr for 4 hrs

  • take back