TKR with incomplete revascularization

PIG Meeting: 24th June 2021

69yo male patient in private hospital for TKR

Background:

  • IHD
    • NSTEMI March ’20, PCI, converted to single antiplatelet therapy after 12/12
    • Admitted recently with unstable angina, possible lateral t wave changes but no trop rise. No angiographic findings suggesting revascularisation required. Some very distal LCA territory disease.
    • Recommenced on DAPT.
    • Ongoing daily GTN for angina at rest.
  • TTE shows mild apical hypokinesis and mildly reduced EF.
  • ? Anti-Phospholipid syndrome
    • Patient diagnosed at one stage as positive
    • Further review by different haematologist and repeat results suggest patient does not have APL syndrome

Discussion

  • Should surgery proceed?
    • GP encouraging patient to delay surgery, await further cardiologist review in 3/12
    • Cardiologist says patient may proceed with surgery now, happy for w/h of clopidogrel
    • Perioperative revascularisation reserved for lesions with a significant vascular territory (left main disease) or symptomatology. ? revasc not being offered despite daily symptoms, as not amenable to stenting.
    • Differential diagnosis:
      • Non-cardiac cause of chest pain due to essentially normal TTE in the setting of daily rest pain (e.g., recurrent PEs due to APL syndrome)
      • Non-anatomical cause for coronary ischaemic pain e.g., coronary artery thromboses from APL syndrome
  • ISCHEMIA trial showed that even with moderate to severe obstructive lesions, routine invasive therapy was not associated with a reduction in major adverse cardiac events compared to optimal medical therapy. (See attached article)
    • Patient leaning towards delaying surgery (which seems sensible from a purely elective surgery perspective) however, unlikely that anything will change before cardiology review to further guide the decision.
    • If surgery does proceed, patient may be a good candidate for postoperative troponin testing.
  • APL syndrome
    • Confusing picture with alternate haematologist views
    • Is perioperative Tranexamic acid safe? Brief literature search suggests, and group consensus was, that TXA use is not associated with increased risk of VTE in this setting.
    • ? impact on stent thrombosis risk

Plan:

  • Patient currently postponing surgery
  • When/if surgery planned in future, formal discussion with current haematologist  to ensure that the APL issue has been fully elucidated
  • Further discussion with treating cardiologist to guide postoperative monitoring/investigations given his IHD.