Download Coronary Surgery in Woman: A Different Tissue

Coronary Surgery in Woman:
A Different Tissue
Friedrich Eckstein
Cardiac Surgery, University Hospital Basel
CABG in Women
Background
STS National Cardiac Surgery Database (US) for
2002 reveals a CABG operative mortality of
3.54% for women versus 2.15 % for men
In several other studies there is considerable evidence that women carry a higher
CABG operative mortality as compared with men but the issue is far from settled (1-10)
- Either unadjusted or adjusted CABG mortality to be higher in women (1,2,4,6-10).
- Unadjusted mortality rates higher in women, (1,4,6,8) but after statistical risk
adjustment, mortality rates were not significantly different.
- Signif. gender differences in both unadjusted and adjusted outcomes. (2,10)
- Unadjusted mortality rates showed no gender difference (11-15)
1) Carey - Ann Thorac Surg 1995
5) Khan - Ann Int Med 1990
9) Zitser - J Thorac Cardiovasc Surg 2002
13) Jacobs - Circulation 1998
2) Edwards - Ann Thorac Surg 1998
6) O’Connor - Circulation 1993
10) Hannan -Am Heart J 1992
14) Koch - J Thorac Cardiovasc Surg 2003
3) Edwards - Ann Thorac Surg 1994
7) Vaccarino - Circulation 2002
11) Abramov - Ann Thorac Surg 2000
15) Mickleborough - Circulation 1995
4) Hammar - J Am Coll Cardiol 1997
8) Woods - J Am Coll Surg 2003
12) Aldea - Ann Thorac Surg 1999
CABG:
Common Preoperative Risk Factors per Gender
Male
Female
Ejection fraction less than 35%
Older age at presentation
Three vessel disease
Angina Class 3 or 4
Repeat operations
Urgent surgical intervention
Recent of significant history of smoking
Preoperative IABP usage
Renal failure
Congestive heart failure
Chronic obstructive pulmonary disease
Previous PTCA
Diabetes mellitus
Hypertension
Peripheral vascular disease
Smaller body surface area
Lower hematocrit
CABG in Women
1. Referral Bias
Review of 2297 patients  CABG  females
more advanced NYHA functional class and older age and
referred for CABG later in the course of their disease,
correlates with increased risk for perioperative death (Khan-Ann Intern Med 1990)
Review of 2473 patients  females hospitalized for CAD underwent
 fewer diagnostic and therapeutic procedures than males, including
coronary revascularization and CABG (Ayanian-N Eng J Med 1991)
Increased referral delay for surgery compared to males (Guru-Circulation 2006)
more frequent presentation with atypical symptoms of MI and resultant
delays in hospital admission that is associated with
increased morbidity.
CABG in Women
2. Underuse of Internal Mammary Artery (IMA)
Women receive IMA conduit in only 60% to 75% of cases ?
Proposed reasons (?): smaller vessels - higher rate of non-elective CABG in women
– sternal infection – history of sternal radiation - arteriosclerotic disease of the
proximal IMA but:
No objective reason to use IMA less frequently in women!
Excess CABG mortality in women may be substantially mitigated with
increased use of the IMA, particularly when LIMA – LAD
Add: Bilateral IMA might reverse negative gender outcome
in CABG
Kurlansky et al., EJCTS 2013
CABG in Women
3. Management of Hyperglycemia
- Clear association of diabetes in CABG with operative mortality as well as
mediastinitis and soft tissue wound infections.
- Diabetes is 40% to 50% more common in CABG women and adverse
clinical impact of diabetes is more pronounced
- Diabetic complications and CABG mortality are linked to the degree of
perioperative hyperglycemia
- Risk of death after CABG is independently related to the degree of
perioperative hyperglycemia
- Hyperglycemia in the first 2 postoperative days is the single most
important predictor of mediastinitis after cardiac surgery.
The optimal blood glucose level is believed to be below 200 mg/dL,
levels in the range of 100 to 150 mg/dL seem to be particularly beneficial.
CABG in Women
4. Intraoperative Management of Anemia
Women have lower hematocrit and smaller body size results in greater
intraoperative hemodilution from the pump prime solution.
Hematocrit levels are typically lowest during the period of CPB.
Hematocrit levels below 22% during bypass are strongly associated with
operative mortality and other postoperative complications. (Defoe-Ann Thorac
Surg 2001, Habib-J Thorac Cardiovasc Surg 2003)
Keeping the nadir hematocrit > 22% during CPB will provide a survival
benefit that particularly targets the female population.(Habib-J Thorac Cardiovasc Surg
2003)
Important: Raising the red blood cell concentration by p.e.:
hemoconcentration - minimizing pump prime volume - modified
ultrafiltration - blood transfusions
CABG in Women
5. OFF PUMP Surgery?
In several studies OPCAB surgery seems to offer some promise
but patient selection has been suboptimal.
IMA is more likely to be used in OPCAB patients compared with
conventional CABG patients.
The favorable results in women undergoing OPCAB suggest the
possibility that avoidance of cardiopulmonary bypass may have
a selective benefit for women.
But: There is no major gender difference in outcomes associated
with valve surgery, it appears unlikely that the pump itself plays
a major role.
(Athanasiou-AnnThorac Surg 2003
Brown-AnnThorac Surg 2002
Capdeville-AnnThorac Surg 2001
Mack-Circulation 2004
Lawton-J Thorac Cardiovasc Surg 2003
Edwards-J Am Coll Cardiol 2001)
CABG in Women
6. Optimization of Thyroxine Treatment
for Women with Hypothyroidism
Hypothyroidism is associated with impaired contractility and an
enhanced risk for myocardial infarction. (Eagle-J Am Coll Cardiol 2004)
In the population undergoing CABG, there is a higher incidence
of hypothyroidism in women as compared with men.
CABG mortality rate was up to 16.7% in women requiring
thyroid replacement therapy. (Zindrou-Ann Thorac Surg 2002)
Maintain woman in euthyreotic state during surgery
Perioperative administration of thyroid hormone.
CABG in Women
7. Preoperative Hormone Replacement Therapy ?
Only few evidence that it may be associated with a reduction
in CABG operative mortality
Hormone replacement therapy is linked to several
complications including serious thromboembolic events
2004 ACC and AHA practice guideline for CABG does not
recommend hormone replacement for women undergoing
CABG and
Women on HRT should have the hormonal therapy
discontinued if CABG is undertaken.
Mortality after CABG:
Alam et al.; Am J Cardiol 2013
Meta-Analysis of 20 studies comparing 688.709 men and 277.783 women
Women are more likely to be older and undergo urgent CABG
Have significantly more comorbidities, including hypertension,
DM, hyperlipidemia, unstable angina, congestive heart
failure, peripheral vascular disease
They experience higher mortality at short-term, midterm and
long-term follow-up compared with men.
Risk profiles between males and females are vastly different.
Females have unique physiology and are not simply „smaller
males“
CABG in Women
Outcomes after CABG
- Higher incidence of small-vessel disease + fewer bypass
grafts + decreased use of the IMA + graft occlusion and
progression of CAD
- Higher incidence of sternal wound infection
- Higher incidence of renal dysfunction
- Females: less likely to undergo repeat revascularization
- Readmission rates higher
females / males 20.5% vs 11%
- Recurrent angina and CHF females / males 15.2% vs 8.5%
Isolated CABG problem?
Comparison of PCI (with DES) Versus CABG in Women With Severe
Narrowing of the LMCA
(from the Women-Drug-Eluting stent for LefT main coronary Artery disease Registry)
Freedom from MACCEs after
PCI (blue line) versus
CABG (green line)
in the propensity score-matched
groups.
Buchanan et al., Am J Cardiol 2014
Women and CABG –
still excellent treatment for complex CAD in women