Cat using gxt to screen for cad moore 10 30-13 (final)

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


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.


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


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)


Treadmill Test: You’re doing it wrong


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


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)


Exercise Stress Testing for CAD


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.


How do we prevent a GXT “Fail”?


CRITICALLY APPRAISED TOPIC

Evaluation of Pre-Test Probability of CAD

Mike Moore, R1


Objectives

• Review case

• Clinical question formulation

• Literature review methods

• Conclusions from literature review


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”


Utilized Resources



In case you still can’t find Ovid…


BMJ 2012;344:e3485 doi: 10.1136/bmj.e3485 (Published 12 June 2012)

COMBINED PREDICTIVE MODELS


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.


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


• 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.


• 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.


SORT

Strength of Recommendation Taxonomy (SORT)


SORT

Strength of Recommendation Taxonomy (SORT)


Summary of Evidence

• Use the DCS:

Duke Chest Pain - CAD Risk Calculator

• Consider use of

COURAGE

calculator (patients

with known CAD for

clinical guidance)

http://www.zunis.org/Duke Chest Pain - CAD Predictor.htm





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


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


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


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.

Date post:	16-Jul-2015
Category:	Health & Medicine
Upload:	mike-moore
View:	134 times
Download:	0 times

Cat using gxt to screen for cad moore 10 30-13 (final)

Health & Medicine