Medical Pharmacology Chapter 43:  Adult Cardiac Procedures

• Overview: Patient History Issues

  •  Assessment of coronary vascular disease

    •  History recent myocardial infarction

    • Resuscitation/hospitalization associated with myocardial arrhythmias

    •  Cardiac drug use

    •  Symptomatology Associated with Severity of CoronaryVascular Disease

  •  Patient history following myocardial infarction (range of  severity)

    •  Better prognosis: short hospitalization; uneventful recovery

    •  Poorer prognosis: if patient required 

      • Intra-aortic balloon pump following myocardial infarction

      • Defibrillation

  •  Assessment of patients cardiovascular status based on post-infarction drug regimen (chronic) 

    • Normal/hyperdynamic cardiac function: ß-adrenoceptor blocking drugs (e.g.,metoprolol (Lopressor); propranolol (Inderal))

    • Severe left ventricular dysfunction (hypotensive state): balloon support; inotropic agents, e.g. dopamine (Intropin) and dobutamine (Dobutrex), nitrate

Primary Reference: Shanewise, JS and Hug, Jr., CC, Anesthesia for Adult Cardiac Surgery, in Anesthesia, 5th edition,vol 2, (Miller, R.D, editor; consulting editors, Cucchiara, RF, Miller, Jr.,ED, Reves, JG, Roizen, MF and Savarese, JJ) Churchill Livingston, a Division of Harcourt Brace and Company, Philadelphia, pp. 1753-1799, 2000.

• Echocardiography

  • "Dilated left ventricle with mitral chordal calcification"-courtesy of Daniel Shindler, M.D., used with permission

   

  • Transesophageal Echocardiographic Images (TEE)

    "Transesophageal echocardiography (TEE)  demonstrating a markedly enlarged ascending aorta.  The aortic valve appears normal, but the leaflets fail to coapt in diastole, allowing a centrally directed jet of aortic insufficiency" Courtesy of The University of Chicago's Echocardiography Lab

     

  • Echocardiography may be helpful in assessing:

    • Overall ventricular function +/-stress challenge (e.g. dobutamine (Dobutrex) challenge) with assessment of ejection fraction.

    • Ventricular wall motion anomalies

    • Mitral valve regurgitation, secondary to left ventricular dilatation or papillary muscle rupture/dysfunction

• Exercise Electrocardiography

  • Notation of heart rate and

  • Observe which ECG leads indicate ischemic change -- these ECG leads may be the most helpful leads to monitor during anesthesia

  • Ventricular dysfunction  unmasked during exercise-- (e.g.,premature ventricular contractions (PVCs), hypotension, rales)

    • Reason the possibility of potential  intraoperative problems which would influence monitoring, anesthetic approaches and therapeutic responses

• Coronary Angiography and Left Ventriculography

  • Atherosclerotic lesion location may be suggestive of:

    • The most appropriate electrocardiographic leads to monitor

    • Potential complications, e.g. ventricular dysfunction (hypokinesis), cardiac arrhythmias

  • Patency status of previous bypass grafts (internal mammary artery/saphenous vein); also:

    • Identifies the previous percutaneous transluminal coronary angioplasty (PTCA)

  • Adequacy of previous PTCA

  • Characteristics of  atherosclerotic coronary disease, diffuseness of disease; and assessment of distal portions of coronary arteries

    • Cardiopulmonary bypass complications: related to revascularization completeness

  • May reveal coronary vasospastic disorder (Prinzmetal's angina)

  • Evidence of ventricular dysfunction:

    • Hypokinesis (poor ventricular contraction (regional))

    • Dyskinesia

    • Akinesis  (absence of ventricular contraction in a region)

    • Aneurysm

    • High left ventricular end diastolic pressures (>15 mm Hg); ejection fraction < 0.5; and left ventricular and diastolic pressures increasing by > 5 mm mm Hg following contrast.

  • Coronary Arteriogram

    • "Normal left coronary angiogram.

    • Left  anterior oblique view (45 degrees) (Left); Left coronary angiogram. 

    • Left anterior oblique view. 

      • Narrow area from disease proximal end of circumflex and top of anterior descending. 

    • Male age 37. Severe angina not controlled by medical treatment": courtesy of SouthBank University, London; used with permission

• Radionuclide Angiocardiography

  • Adequacy of myocardial perfusion (thallium uptake study) +/-stress [exercise, dobutamine (Dobutrex) challenge]

  • Myocardial infarction identification: (technetium 99 uptake)

  • Evaluation ventricular function (equilibrium-gated blood pool imaging)

    • Estimation of ejection fraction

  • Uncovering inducible myocardial ischemia (stress thallium scan indicates  reperfusion to ischemic regions)

  • Thallium Scans

    • Thallium  Scanning

      "Top two panels of short axes slices shows severe stress perfusion defects involving the septum and inferior walls Bottom left panel of vertical long axis slices shows severe stress perfusion defect involving the apex and interior walls Bottom right panel of horizontal   long axis shows a severe stress perfusion defect involving the septum.  The lateral wall in all views appear normal The inferior and septal walls redistribute completely in the rest 4 hour views indicating ischemia. This represents a small area of infarction"  Background-Thallium scans Diagnostic Testing, Andrew F. McLaughlin, Nuclear Medicine Physician, Sydney (Aust Prescr 1994; 17; 3; 57-60);

       

• Primary Reference:  Ross, AF, Gomez, MN. and Tinker, JH Anesthesia for Adult Cardiac Procedures in  Principles and Practice of Anesthesiology (Longnecker, D.E., Tinker, J.H. Morgan, Jr., G. E., eds)  Mosby, St. Louis, Mo., pp. 201-218, 1998.

• Primary Reference: Shanewise, JS and Hug, Jr., CC, Anesthesia for Adult Cardiac Surgery, in Anesthesia, 5th edition,vol 2, (Miller, R.D, editor; consulting editors, Cucchiara, RF, Miller, Jr.,ED, Reves, JG, Roizen, MF and Savarese, JJ) Churchill Livingston, a Division of Harcourt Brace and Company, Philadelphia, pp. 1753-1799, 2000.

• Primary Reference: Wray Roth, DL, Rothstein, P and Thomas, SJ Anesthesia for Cardiac Surgery, in Clinical Anesthesia, third edition  (Barash, PG, Cullen, BF, Stoelting, R.K, eds), Lippincott-Raven Publishers, Philadelphia, pp. 835-865, 1997