Table 1

Risk factors Not Captured by Traditional Risk Scores

ComorbiditiesDefinition/CriteriaDiagnostic Modalities
Porcelain aorta or severely atherosclerotic aortaHeavy circumferential calcification or severe atheromatous plaques of the entire ascending aorta extending to the arch such that aortic cross-clamping is not feasibleNon-contrast axial CT at levels: Sinotubular junction Tubular ascending aorta between the sinotubular junction and the innominate artery Innominate artery Entire transverse arch
Frailty
  • Slowness, weakness, exhaustion, wasting and malnutrition, poor endurance and inactivity, loss of independence

  • Criteria:

  •  5 m walking time

  •  Grip strength

  •  BMI <20 kg/m2 and/or weight loss 5 kg/year

  •  Serum albumin <3.5 g/dL

  •  Cognitive impairment or dementia

  • Medical history

  • Physical examination

  • Physical performance measures

  • Cognitive assessments

  • Laboratory tests

Severe liver disease/cirrhosis
  • Any of the following:

  •  Child-Pugh class C

  •  MELD score >10

  •  Portal-caval, spleno-renal, or transjugular intrahepatic portal shunt

  •  Biopsy proven cirrhosis with portal hypertension or hepatocellular dysfunction

  • Medical history

  • Physical examination

  • Laboratory tests

  • Child-Pugh classification

  • MELD score

  • Liver biopsy

Hostile chest
  • Any of the following or other reasons that make redo operation through sternotomy or right anterior thoracotomy prohibitively hazardous:

  •  Abnormal chest wall anatomy due to severe kyphoscoliosis or other skeletal abnormalities (including thoracoplasty, Potts' disease)

  •  Complications from prior surgery

  •  Evidence of severe radiation damage (e.g. skin burns, bone destruction, muscle loss, lung fibrosis, or oesophageal stricture)

  •  History of multiple recurrent pleural effusions causing internal adhesions

  • Medical history

  • Physical examination

  • Chest X-ray

  • CT scan

IMA or other critical conduit(s) crossing midline and/or adherent to posterior table of sternum
  • A patent IMA graft that is adherent to the sternum such that injuring it during re-operation is likely. A patient may be considered at extreme risk if any of the following are present:

  •  The conduit(s) are radiographically indistinguishable from the posterior table of the sternum.

  •  The conduit(s) are radiographically distinguishable from the posterior table of the sternum but lie within 2–3 mm of the posterior table

  • Axial CT scan images illustrating the graft crossing the midline so that the distance from sternum to graft can be measured.

  • Angiogram from the lateral and PA projections and/or a CPRorVR (volume rendering) 3D reconstructed CT scan image showing relationships between the graft and the sternum

Severe pulmonary hypertension Severe right ventricular dysfunction
  • Primary or secondary pulmonary hypertension with PA systolic pressures greater than two-thirds of systemic pressure

  • Criteria as defined by the guidelines (e.g. TAPSE <15 mm, RV end-systolic area >20 cm2, etc.)

  • Echocardiography, right and left-heart-catheterization documenting PA and systemic pressures

  • Documentation of secondary causes of pulmonary hypertension

CT = computed tomography; MELD = Model for End-Stage Liver Disease; INR = international normalized ratio; IMA = internal mammary artery; PA = pulmonary artery.

  • Variable with respect to age and gender without validated scientific thresholds.

  • Rudski et al. (71).