Beyond randomised studies: recommendations for cardiac rehabilitation following repair of thoracic aortic aneurysm or dissection

Thoracic aortic aneurysms or dissection are associated with high morbidity and mortality.^1–3 In addition, these patients might exhibit significant cardiovascular risk factors beyond hypertension causing concomitant coronary syndromes, heart failure, stroke or peripheral arterial disease.^1–3 Exercise-based cardiac rehabilitation (CR) is able to control atherosclerotic risk and to reduce morbidity and mortality in patients with coronary artery disease.⁴ The prescription of exercise, however, remains a dilemma in patients following aortic repair, and data about CR in this cohort are sparse. Hence, there is uncertainty about the earliest time that patients should be allowed to start with exercise training and at what intensity.^1–3

So far, four studies or registries about exercise after aortic dissection^5–8 (Table 1) have been published. In addition, commentaries,⁹ editorials¹⁰ and a patient page of the American Heart Association¹¹ have promoted physical activity for post-aortic dissection patients. However, there are no position statements or guidelines about CR in patients immediately following surgical repair of thoracic aortic aneurysm or dissection.¹² Therefore, the German, Swiss and Austrian Associations for Prevention and Rehabilitation of Cardiovascular Diseases (DGPR, SCPRS, ÖKG) have prepared a proposal to start CR as early as possible without neglecting the potential risks in this patient cohort.¹³

Table 1

Overview of studies or registries on exercise after aortic dissection.

Study	Patients age	Indication	Time after surgery	Exercise test	Blood pressure max. (mmHg)
Corone et al., 20095 prospective	n = 33 55 ± 9	De Bakey type 1	27 ± 21 days (range 10–110)	Bicycle ergometer	At peak exercise 50% patients: 150–160 25% patients: <170
Delsart et al., 20166 prospective	n = 105 58 ± 12	Stanford A and B	22 ± 30 months	Bicycle ergometer	At VT systolic: 151 ± 22 diastolic: 77 ± 14
Fuglsang et al., 20177 retropsective	n = 10 56 ± 7	Stanford A	6–12 weeks	Bicycle ergometer	At peak exercise 200 ± 32
Hornsby et al., 20208 retrospective	n = 128 59 (range 48–66)	Stanford A and thoracic aortic aneurysm	2.9 months (interquartile range 1.8–3.5)	Bicycle ergometer	At peak exercise 160/70 (interquartile range 144–172/62–80)

VT: ventricular tachycardia.

Bicycle exercise was performed in all the afore-mentioned four studies without complications, either as standard⁵ or as cardiopulmonary exercise testing.^6–8 In addition, participation in CR activities was safe and well tolerated in all patients. Physical capacity was increased significantly by 46% (P = 0.002) from 63 ± 12 to 92 ± 17 Watts,⁵ or by 24% (P = 0.003) from 143 ± 80 to 178 ± 97 Watts,⁷ respectively, and peak oxygen consumption (VO_2peak) was increased significantly by 22% (P = 0.001) from 24 ± 8 ml/min/kg to 29 ± 8 ml/min/kg.⁷ At the end of the CR programme, blood pressure (BP) at rest was significantly better controlled,^5,7 there was a tendency towards better quality of life as measured by the short form 36 (SF36) questionnaire,⁷ and in one small study 10 out of 19 patients of working age were able to return to work.⁵ However, only that particular study⁵ included patients early after surgery for aortic dissection (Table 1).

Keeping in mind the limited data, the potential complications and benefits of CR participation need to be evaluated and balanced. Therefore, the following proposals were made for patients in the early phase after surgical/interventional repair of thoracic aortic aneurysm and/or dissection (Table 2).¹³

Table 2

General recommendations and training instructions.

General recommendations
Start of CR	• As early as possible  • In close contact with the surgical clinic  (incl. transfer of pre- and post-operative information)
Blood pressure (BP)	• Tight control at rest (< 130/80 mmHg) is mandatory  • Confirmed by repeated measurements or by 24-h automatic BP measurement, if effective control is doubted (2) • Exercise test should be performed cautiously and systolic BP should not exceed 160 mmHg (5-8) • Exercise training should be limited to systolic BP ≤160 mmHg  • BP should be measured at the beginning, during and immediately after exercise training
Training instructions
Aerobic exercise intensity	• 3-5 Metabolic Equivalent of Tasks (METs)  • Rating of Perceived Exertion (RPE) 12-13/ 20 on Borg Scale  • Cycling up to 15 km/h or brisk walking on flat grounds are considered to be safe (11)
Dynamic strength training	• straining must be strictly avoided  • muscle training must be stopped before beginning of muscle fatigue  • use low weights and increase the number of repetitions
Competitive sport and isometric components	• should be strictly avoided

During CR all physical exercise activities including dynamic strength training are principally feasible. It is mandatory to individualize these activities according to the severity of the disease, postsurgical results, physical fitness, comorbidities and/or other impairments. In conclusion, CR should be an integrated part in the therapy of patients following the repair of thoracic aortic aneurysm or dissection to prevent an unnecessarily prolonged immobilisation by starting early a cautiously dosed programme with physical exercise and concomitant medical supervision to control cardiovascular risk factors. In addition, reintegration into activities of daily living as well as psychosocial therapy of post-traumatic problems are mandatory. In younger patients, it is important to reduce their fear of exertion during leisure time or sexual activity, and their return to work needs to be strongly supported. Multicentre registries (under the auspices of the European Association of Preventive Cardiology) or controlled studies are urgently needed to validate whether these proposals are safe and effective within the setting of CR in order to make CR a standard indication following the repair of thoracic aortic aneurysm or dissection.¹²

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.