Myths and methodologies: Cardiopulmonary exercise testing for surgical risk stratification in patients with an abdominal aortic aneurysm; balancing risk over benefit

Figures

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  FIGURE 1. Clinical presentation of an abdominal aortic aneurysm (AAA). (a) Surgical appearance of a large (8.5‐cm‐diameter) infrarenal AAA during open transperitoneal repair. (b) Anatomical classification of AAAs: i, infrarenal AAA; ii, juxtarenal AAA; iii, suprarenal AAA; iv, type IV thoracoabdominal aortic aneurysm. (c) Appearance on ultrasound (transverse plane), enabling assessment of anteroposterior (i) and transverse (ii) diameters. (d) Coronal maximum‐intensity projection (i) and three‐dimensional reformat (ii) of an AAA (5.5 cm in diameter). Note the adequate length of the iliac arteries and the long infrarenal neck below the renal arteries, highlighting suitability for endovascular repair. (d) Adapted from (Swerdlow et al., 2019).

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  FIGURE 2. Contrast‐enhanced computed tomography scans of a ruptured abdominal aortic aneurysm (AAA). The scans illustrate a large (9.0‐cm‐diameter) ruptured AAA in a single patient. (a) Axial plane; note the crescent sign (rim of hyperdensity, continuous arrow) within the mural thrombus (dotted arrow), with a retroperitoneal haematoma visible anterior to the psoas muscles (asterisks). (b) Sagittal plane.

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  FIGURE 3. Open repair and endovascular repair of abdominal aortic aneurysm (AAA). (a) Left panel, open transperitoneal AAA repair, showing a bifurcated synthetic prosthetic graft, with a proximal anastomosis at the infrarenal neck and distally to the origin of both common iliac arteries. (a) Right panel, open retroperitoneal repair of a juxtarenal AAA with the duodenum and left ureter seen to the left of the open aortic sac. (b) Coronal maximum‐intensity projection, with endovascular stent graft deployed. Note uncovered struts above the renal arteries and covered extensions into both iliac arteries to ensure that no endoleak develops.

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  FIGURE 4. Vascular mechanobiological forces associated with exercise and risk of abdominal aortic aneurysm (AAA) rupture. Long‐term exercise is performed by AAA patients during the course of surgical prehabilitation and typically takes the form of submaximal to (supra)maximal high‐intensity interval training (HIIT). An acute incremental exercise trial to volitional exhaustion is also performed during cardiopulmonary exercise testing (CPET) to assess perioperative risk (Rose et al., 2022). Long‐term benefits: Long‐term moderate‐intensity continuous training (MICT) employing aerobic and/or resistance exercise is generally considered safe and well tolerated, assuming mean arterial pressure (mean aterial pressure (MAP) or pressure (p)) is controlled (see Section 6 Clinical Recommendations), with the capacity to elevate cardiorespiratory fitness (CRF) and improve peri‐operative outcome, including long‐term survival (Haque et al., 2022). Submaximal training in patients with occult small AAAs (3.0–5.5 cm) in the absence of aortic dissection/leak is advocated by respected authorities including, albeit not exclusively limited to, the American Heart Association/American College of Cardiology (Hirsch…

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  FIGURE 5. Modified algorithm based on previously published guidelines (ACSM, 2010; American Thoracic Society, 2003; Laveneziana et al., 2021; Levett et al., 2018; Pelliccia et al., 2021; Pritchard et al., 2021; Radtke et al., 2019), highlighting a systematic approach to clinical stratification, precautions, optimization and corresponding risk mitigation during cardiopulmonary exercise testing (CPET) in patients with an abdominal aortic aneurysm (AAA). Note that CPET data should be interpreted by a specialist and functionally integrated with other clinical findings, including surgical/anaesthetic factors, AAA diameter/morphology and resting/exercise blood pressure responses, with the last of these monitored continuously (as highlighted). *Please refer to Table 1. Abbreviations: CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; EVAR, endovascular repair; ILD, interstitial lung disease; MDT, multidisciplinary team; PE, pulmonary embolus. Turndown refers to a patient deemed unsuitable for surgical repair of AAA.