Risk For MI After Arthroplasty

Present by R2 Choopong Luansritisakul R2 Jittrawan Attawattanakul

Supervise by Assoc.Prof. Sirilak Suksompong

• A 81 year-old man• Admit for Elective total hip replacement• Underlying disease : HT on Atenolol (50) 1x1 DLP on Simvastatin (20) 1x1 Old CVA 4year ago (full

recovery) Previous MI 11 months ago • Choice of anesthesia : GA with ETT• Intraoperative : no complication• POD 7 : typical angina , ECG CK-MB 2.7 (0-3ng/ml), Trop-T 1.78(0-

0.2ng/ml) Imp NSTEMI

Postoperative MI ?

• Acute Myocardial Infarction• Definition

• Detection of and/or of cardiac biomarker values (preferably cardiac troponin) with > value above the 99th

percentile upper reference limit and with > one of the following :

Circulation, published online August 24,2012;2012 American Heart Association,Inc.

• Symptoms of ischemia• New or presumed new significant ST-T

changes or new LBBB• Development of pathological Q waves in

ECG• Imaging evidence of new loss of viable

myocardium or new regional wall motion abnormality

• Identification of an intracoronary thrombus by angiography or autopsy

Circulation, published online August 24,2012;2012 American Heart Association,Inc.

• LBBB

• Postoperative Myocardial Infarction• Often recognized late (postoperative day 3

- 5), resulting in high (30% - 70%) mortality

Morbidity and Mortality Incidence

From Anesthesiologist records in last year

9 case

Diagnosis Operation

Corneal ulcer with perforation LE

AMT patch with CT LE

Submandibular gland tumor Fibular free flapBPH TUR-BTAAA EVARESRD AVFAcute appendicitis AppendectomyPerianal abscess I&DCA larynx Total laryngectomySAH Craniotomy

Perioperative MI

Myocardial InfarctionVS

Total Hip or Knee Replacement

Study Year

No. of patien

ts

%Post-MI

F/U Design

Mantilla et al.

2002

10,244 0.4 30 d cohort

Gandhi et al.

2006

3,471 1.8 30 d retrospective

Parvizi et al.

2007

1,636 0.37 6 wk

cohort

Pulido et al.

2008

15,383 0.27 D/C cohort

Khatod et al.

2008

17,080 0.1 90 d retrospective

• Limitation such as • small sample sizes• lack of matched control • only focused on short-term • no analysis for medication

Strengths

• The nationwide population-based design• Large sample size• Information on matched controls• Completeness of follow-up

• Nationwide matched control retrospective cohort study

• The Danish national registries

Inclusion criteria

• Patients who underwent a primary THR or TKR surgery

• January,1998 to December, 2007• Age 18 years or older

Exclusion criteria

• Prior AMI within 6 weeks before

95,664 Patients

THR group (n=66,524

)

TKR group (n=28,703

)

Control group

(n=86,164)

Control group

(n=200,001)

Followed up until - Death- Migration- Revision THR or TKR- End of study period- Acute myocardial

infarction

437 patients excluded

Thromboprophylaxis

Thromboprophylaxis

• Incidence of acute myocardial infarction• Potential risk factors

• Age • Sex • History of AMI, heart failure,

cerebrovascular disease • Drug dispensing within 6 months

F/U time(yr) Male(%) Age,mean(yr)

IHD (%) CHF (%)01020304050607080

3.9

36.9

71.9

12.5 7.94.1

36.9

71.9

10.5 6.5

Exposed(n=66,524) Unexposed(n=200,001)

Baseline Characteristics of patients Undergoing THR and Matched control

NSAIDs B-Blockers Statins Antiplatelet0

10

20

30

40

50

6050.7

13.28.7

22.316.4

12.18.7

20.9

Exposed (n=66,524) unexposed (n=200,001)

Drug use within previous 6 mth (%)

2 weeks

6 weeks

THR TKR0

5

10

15

20

25

30

2.41 2.26

12.49.2

25.3

11.2

18-59yr 60-79yr >80yr

Adjusted HR(6-wk risk for AMI)

Effect Modifiers of AMI risk after THR or TKR vs Matched controls

Adjusted HR (6wk risk for AMI)

THR TKRPrevious MI 2.12 (1.59-2.83) 1.15 (0.55-

2.42) 1.5-6 mo before

4.25 (2.24-8.05) 4.14 (0.91-18.87)

6-12 mo before 3.82 (1.90-7.67) 2.18 (0.28-16.79)

>12 mo before 1.91 (1.40-2.59) 0.96 (0.43-2.17)

Adjusted HR (6wk risk for AMI)

THR TKRNSAIDs 1.80 (1.31-

2.47)1.64 (0.78-

3.42)B-Blockers 1.45 (1.11-

1.88)1.49 (0.82-

2.67)Platelet inhibitors 1.33 (1.03-

1.73)2.30 (1.21-

4.37)

Adjusted HR (6wk risk for AMI)

THR TKRHeart failure 2.47 (1.90-

3.20)3.75 (2.01-

6.98)Cerebrovascular disease

2.06 (1.57-2.70)

2.09 (1.05-4.15)

MarrowEmbolization

AntithromboticAgents

Limitations

• Lack of information on other risk factors for AMI• smoking, blood pressure, biochemical

variables, and BMI• No information on inpatient anticoagulant

use• No information about GA or RA

GA vs RA

• General anesthesia vs Regional anesthesia showed a trend toward only 1.4 fold increase risk of AMI

Anesthesia for hip fracture surgery in adults (Review)2004 The Cochrane Collaboration

• Increase risk of AMI during the first 2 weeks after arthroplasty

• AMI within 1 year should be contraindication for undergoing elective THR surgery

• Prophylactic therapy• Adrenergic Blockers• Statins• Calcium channel Blockers• 2 Agonists• Aspirin

• Prophylactic therapy• Adrenergic Blockers

• Long term should not be discontinued• No study has compared prophylactic B-

Blockade with short term

• Prophylactic therapy• Adrenergic Blockers• Statins

• Abrupt withdrawal cause plaque destabilization

• Reduced perioperative and long term cardiac complication

• Large randomized controlled trials are still needed

Perioperative Management• Correct tachycardia, hypertension,

hypotension, and pain• Tight hemodynamic monitoring• Blood transfusion in patients with CAD and

Hb<10• Coronary intervention and antithrombotic

therapy

Take Home Messages• New definition of AMI • THR and TKR patients increased risk of AMI

during the first 2 weeks after surgery• Elective THR and TKR should be

contraindicated in patients with previous MI in last 1 year before

• Management for decrease risk of postoperative MI are necessary

THANK YOU