Few teams in the world can reliably analyze tissue microbiota. In this regard, the present group has unique expertise in the analysis of blood and tissue microbiota, the first to describe in 2011.

Having a blood biomarker of this valve microbiota could help guide the therapeutic strategy before and after the intervention. This study will be the first to test the hypothesis that the analysis of the blood microbiota makes it possible to detect the carriage of a tissue microbiota in patients undergoing aortic valve replacement (AVR) for degenerative aortic valve disease and should also lay the foundations for a prospective study. intended to evaluate the impact of the blood and valve microbiota on the post-operative prognosis of these patients and the complications at one year. This would be a first proof of concept of the role of the tissue microbiota in valvular degeneration linked to aging.

Inclusion Criteria:

• Indication for surgical AVR:

  • Tight RA:

    • symptomatic (dyspnea, syncope/lipothymia, angina);
    • and/or echocardiographic criterion:

• valve surface < 1cm2 (and/or 0.6cm2/m2);

• average transvalvular gradient > 40mmHg;

• aortic jet velocity (Vmax) > 4.0m/s;

  • or low transvalvular gradient (mean gradient < 40mmHg) + left ventricular ejection fraction (LVEF) < 50% but contractile reserve;

  • and/or high calcium score on CT angiography;

    • Asymptomatic tight RA and:

  • LVEF < 50% without other cause;

  • and/or symptoms during exercise;

  • and/or low surgical risk + severity criteria: Vmax > 5.5m/s (or progression > 0.3m/s/year), NT-proBNP level > 3Xnormal, severe pulmonary arterial hypertension (pulmonary systolic pressure > 60mmHg);

    • Moderate AR + concomitant surgical indication for another heart disease;
    • Severe AI: regurgitant orifice > 30mm2, regurgitated volume > 60ml/beat,

  • symptomatic (dyspnea, syncope/lipothymia, angina);

  • and/or left ventricular dysfunction: LVEF < 50%, end-diastolic diameter > 70mm, end-systolic diameter > 50mm (or > 25mm/m2);

  • and/or concomitant surgical indication for another heart disease.