Severe aortic stenosis management in heart valve centres compared with primary/secondary care centres

OBJECTIVE

Current guidelines recommend use of heart valve centres (HVCs) to deliver optimal quality of care for patients with valve disease but there is no evidence to support this. The hypothesis of this study is that patient care with severe aortic stenosis (AS) will differ in HVCs compared with satellite centres. We aimed to compare the treatment of patients with AS at HVCs (tertiary care hospitals with full access to AS interventions) to satellites (hospitals without such access).

METHODS

IMPULSE enhanced is a European, observational, prospective registry enrolling consecutive patients with newly diagnosed severe AS at four HVCs and 10 satellites. Clinical characteristics, interventions performed and outcomes up to 1 year by site-type were examined.

RESULTS

Among 790 patients, 594 were recruited in HVCs and 196 in satellites. At baseline, patients in HVCs had more severe valve disease (higher peak aortic velocity (4.3 vs 4.1 m/s; p=0.008)) and greater comorbidity (coronary artery disease (CAD) (44% vs 27%; p<0.001) prior myocardial infarction (MI) (11% vs 5.1%; p=0.011) and chronic pulmonary disease (17% vs 8.9%; p=0.007)) than those presenting in satellites. An aortic valve replacement was performed more often by month 3 in HVCs than satellites in the overall population (52.6% of vs 31.3%; p<0.001) and in symptomatic patients (66.7% vs 43.2%, p<0.001). One-year survival rate was higher for patients in HVCs than satellites (HR2.19; 95% CI 1.28 to 3.73 total population and 2.89 (95%CI 1.64 to 5.11) for symptomatic patients.

CONCLUSIONS

Our data support the implementation of referral pathways that direct patients to HVCs performing both surgery and transcatheter interventions.

TRIAL REGISTRATION NUMBER

NCT03112629.

Caseload management and outcome of patients with aortic stenosis in primary/secondary versus tertiary care settings-design of the IMPULSE enhanced registry

Background

Severe aortic stenosis (AS) is one of the most common and most serious valve diseases. Without timely intervention with surgical aortic valve replacement or transcatheter aortic valve replacement, patients have an estimated survival of 2–3 years. Guidelines for the treatment of AS have been developed, but studies suggest that as many as 42% of patients with AS are not treated according to these recommendations.

The aims of this registry are to delineate the caseload of patients with AS, outline the management of these patients and determine appropriateness of treatments in participating centres with and without onsite access to surgery and percutaneous treatments.

Methods/design

The IMPULSE enhanced registry is an international, multicentre, prospective, observational cohort registry conducted at four central full access centres (tertiary care hospitals) and at least two satellite centres per hub (primary/secondary care hospitals). An estimated 800 patients will be enrolled in the registry and patient follow-up will last for 12 months.

Discussion

In addition to the primary aims determining the caseload management and outcome of patients with AS in primary, secondary and tertiary care settings, the registry will also determine a time course for the transition from asymptomatic to symptomatic status and the diagnostic steps, treatment decisions and the identification of decision-makers in tertiary versus primary/secondary care hospitals. The last patient will be enrolled in the registry in 2018 and results of the registry are anticipated in 2019.

Registration number

NCT03112629.

High-cholesterol + vitamin D2 regimen: a questionable in-vivo experimental model of aortic valve stenosis

BACKGROUND AND AIM OF THE STUDY

Recent data have shown that aortic valve stenosis (AS) is an active and highly regulated process which shares similarities with atherosclerosis. However, AS cannot be considered as a purely atherosclerotic phenomenon, and a hypercholesterolemic rabbit model might not be fully representative of human AS pathophysiology.

METHODS

Twenty-eight New Zealand White rabbits were assigned to three groups: group 1 (no dietary supplement for three months); group 2 (0.3% cholesterol-enriched-diet + 50,000 IU/day vitamin D2 for six months); and group 3 (1% cholesterol-enriched-diet + vitamin D2 for three months). The peak aortic gradient and permeability index (outflow tract/aortic velocity-time-integral) were assessed, as well as calcium staining within the aortic valve and ascending aorta.

RESULTS

AS hemodynamic severity was not different among the groups. The peak gradient was 4 +/- 2 mmHg at baseline, 4 +/- 2 mmHg at three months in controls, 4 +/- 1 mmHg at three months and 6 +/-3 mmHg at six months in group 2, and 4 +/- 1 mmHg at three months in group 3 (p = NS). The permeability index was 64 +/- 7 at baseline, 60 +/- 12 at three months in controls, 63 +/- 14 at three months and 58 +/- 12 at six months in group 2, and 60 +/- 5 at three months in group 3 (p = NS). The aortic valve of cholesterol-enriched-diet rabbits was thickened but not calcified, whereas the ascending aorta was both thickened and calcified.

CONCLUSION

When using a hypercholesterolemic rabbit model plus vitamin D2, no adverse hemodynamic effect or aortic valve calcification was observed, despite a high-level and prolonged cholesterol-regimen supplementation. These results raise questions with regard to the extrapolation of this animal model to humans.