Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Case
• 63yo M /c PMH of HLD/HTN, s/p TBI & subsequent temporal lobectomy for persistent seizures
• Presents with severe 9/10 back pain starting 24 hours ago, evaluated in ED
– CTPA/cTnT x1 negative, required IV opioids for pain control in ED
– Further Hx: CP 1-2/10 associated with dyspnea/cough while walking on treadmill at home for 20-30 minutes
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Case
• Additional PMHx/PSHx: LBP/HNP L4-5 with broad bulge & mild NF impingement on MRI 2012
• FSHx: Occasional Etoh; 10 PY smoking hx, quit 10 years ago; Mother SCD/ACS 42 years of age (heavy smoker)
• Meds: ASA, ACEI, B-blocker, Vytorin; Topamax/Clonazepam for seizures.
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Case
• PE:
– VSS, AOx3, NAD
– HS RRR /s M, Lungs CTAB
– Left Chest Wall TTP, L-Spine paraspinal TTP
– No edema, or focal neuro findings
• Labs/Imaging:
– CMP/CBC WNL, cTnT negative, Last Lipids Jul 13 LDL 57, HDL/TG WNL
– CT Head NAIP, CTPA NEOD, pCXR NACPD
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Case
• Cardiac Diagnostics:
– EKG no acute changes compared to previous studies
– GXT 2007 Full Bruce Protocol /s evidence of ischemia, low risk study. Baseline chest wall pain 2/10 before and after study.
• Seen in ED, or ED follow up: What Now?
– 63 yo M with back & atypical CP, also with multiple cardiac RF (age, lipids, smoking, FH)
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Case
• GXT Performed:
– Modified Bruce 13:30, 9.2 METS, max effort
– RHR 55 achieved MHR 148 (94% predicted)
– No BP drop, ST depression 1mm at peak & all 5 minutes of recovery
• LHC /c CA: 70-80% obstruction mid-LAD, subsequent PTCA /c stenting of same
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Exercise Stress Testing for CAD
• Graded Exercise Stress Test
– Simple/Cheap/Effective (if used properly)
– Evaluates Exercise Tolerance & ECG Changes related to CAD
– Highly dependent on determination of pretest probability of CAD
• Pretest Probability
– Age/Gender/Pain Character (DFM)
– DM/Smoking/HLD/Q-waves (Duke)
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
DFM Compared To DCS
Am J Cardiol. 2012 Apr 1;109(7):998-1004. doi: 10.1016/j.amjcard.2011.11.028. Epub 2012 Jan 9.
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
CRITICALLY APPRAISED TOPIC
Evaluation of Pre-Test Probability of CAD
Mike Moore, R1
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Objectives
• Review case
• Clinical question formulation
• Literature review methods
• Conclusions from literature review
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Clinical Question
• Population
– Primary Care population at risk of CAD
• Intervention
– Improve diagnostic efficiency for CAD
• Comparison
– Evaluate DF vs. DCS estimation of rick of CAD
• Outcome
– Reduce unnecessary testing
“What is the best way to determine the pretest probability of CAD”
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
BMJ 2012;344:e3485 doi: 10.1136/bmj.e3485 (Published 12 June 2012)
COMBINED PREDICTIVE MODELS
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Major Studies
• Prediction model to estimate presence of coronary artery disease: retrospective pooled analysis of existing cohorts– BMJ 2012;344:e3485 doi: 10.1136/bmj.e3485
(Published 12 June 2012)
• Comparison of the Diamond-Forrester method and Duke Clinical Score to predict obstructive coronary artery disease by computed tomographic angiography– Am J Cardiol. 2012 Apr 1;109(7):998-1004. doi:
10.1016/j.amjcard.2011.11.028. Epub 2012 Jan 9.
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Clinical Question - Background
• Determination of the Pretest Probability of CAD
– Diamond and Forrester method (DFM)
• Age, Gender, Character of Pain
– Duke Clinical Score (DCS)
• DFM + Smoking, DM, HLD, Q-waves on EKG
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
• DFM:
– 18% low, 65% intermediate, 17% high risk
• DCS: 53% of patients had a reclassification of their risk (most changed from intermediate to low or high risk)
– 50% low, 19% intermediate, 35% high risk
• Net reclassification improvement for the prediction of obstructive CAD was 51%
Which Method is Best?
Am J Cardiol. 2012 Apr 1;109(7):998-1004. doi: 10.1016/j.amjcard.2011.11.028.
Epub 2012 Jan 9.
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
• Search strategy
• Study inclusion criteria
• Obtain primary data
• Prepare data for pooled analysis
• Estimate study-specific effects
• Examine whether results are heterogeneous
• Estimate pooled result
• Conduct sensitivity analyses
Outline for Conducting Pooled Analyses
Friedenreich CM, Methods for pooled analyses of epidemiologic studies. Epidemiology; 1993; 4:295-302.
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
SORT
Strength of Recommendation Taxonomy (SORT)
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
SORT
Strength of Recommendation Taxonomy (SORT)
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Summary of Evidence
• Use the DCS:
Duke Chest Pain - CAD Risk Calculator
• Consider use of
COURAGE
calculator (patients
with known CAD for
clinical guidance)
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Bottom Line
• Routinely use a Combined Prediction Model (DCS or CAD Consortium) for Predicting the Pretest Probability of CAD
– Rational to use FH, Smoking, HLD, HTN for adjustment of pretest probability
– Timing of pain is important
• Reassess Risk of CAD (Frequency?)
– Every 2-3 years is rational
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Current Research
• Ongoing Research
– Evaluate new modalities of CV Non-Invasive Diagnostics
– Health System Utilization
• Future Directions
– Reassessment of risk/disease
– Evaluation after medical treatment
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
Effect on Patient Case
• In this case:
– The patient was reassessed
– GXT was performed
– Critical LAD lesion identified and stented
• Outcome was excellent
• Key Point: Use of the “Cardiac 4”– ASA, ACEI, BB, Statin
Madigan Army Medical Center IM Oral Exam Workgroup 5 APR 2013
References
(in addition to those already cited)
• Up To Date:– “Exercise ECG testing to determine prognosis of
coronary heart disease“– “Stress testing for the diagnosis of coronary heart
disease“
• Diamond GA, Forester JS. Analysis of probability as an aid in the clinical diagnosis of coronary-artery disease. NEJM 1979;300:1350-8
• Pryor DB et al (from Duke University) Estimating the likelihood of significant coronary artery disease Am J Med 1983;75:771-80.