The goal of this clinical trial is to learn if acute transcatheter aortic valve implantation (TAVI) is superior to standard treatment (stabilization in an intensive care unit and TAVI subsequently) to treat cardiogenic shock in patients with critical severe aortic stenosis.

The main questions it aims to answer are:

• Does acute TAVI increase survival compared with standard treatment?

Participants will:

• Undergo either TAVI within 12 hours after admission or stabilization and TAVI 72 hours or more after admission
• Visit an outpatient clinic and be evaluated for quality of life and heart function

Aortic stenosis (AS) is a condition where the heart's aortic valve narrows. With an estimated prevalence of 12% in individuals aged 75 years and above, it is the most common heart valve disease. The progressive narrowing increases the afterload on the heart, impairing its ability to maintain cardiac output. The end-stage of critical AS is cardiogenic shock (CS) with an incidence of 3.5% to 12%. Without treatment, patients develop acute decompensation, organ failure, and ultimately die.

Guidelines suggest balloon aortic valvuloplasty (BAV), hemodynamic optimization in the intensive care unit and surgical aortic valve replacement or transcatheter aortic valve implantation (TAVI) when the patient is stable. Even with BAV, the 30-day mortality is 33%-47% and a 1-year mortality is 70%. Further, the BAV procedure is associated with only a minor and likely temporary reduction in afterload due to elastic valvular tissue. Furthermore, the BAV procedure has been abandoned as a routine intervention in these patients due to a series of patients having limited immediate clinical response, a risk of deterioration and no impact on overall mortality risk. Moreover, most patients with critical AS in CS are not candidates for surgical aortic valve replacement because of increased peri-operative risk of morbidity and mortality.

Despite the recommendation on TAVI under stable conditions, an acute TAVI may be efficient in afterload reduction and more efficient than the limited and transient effects of BAV. TAVI has become an attractive alternative to surgery and BAV because of the less invasive nature of this procedure, yet permanent result (compared with BAV). It is already approved for the treatment of AS irrespective of CS status. This raises the question:

"Should acute TAVI be the new preferred treatment strategy in AS patients in Cardiogenic shock?"

In this randomized controlled trial, we will include patients with severe aortic stenosis and cardiogenic shock. Patients will undergo either acute TAVI or standard treatment (stabilization in a cardiac intensive care unit and subsequently TAVI) in a 1:1 ratio. Outcomes are evaluated 90 days after randomization and comprise days alive out of hospital, mortality, cardiac function, renal function, and quality of life.

Inclusion Criteria:

• Aortic valve area less than 1cm2

AND

Cardiogenic Shock defined as:

• Peripheral signs of tissue hypoperfusion (arterial blood lactate ≥2.5mmol/l) AND
• Systolic blood pressure < 100 mmHg and/or need for vasopressor therapy (dopamine/ norepinephrine or epinephrine) AND
• Left ventricular ejection fraction ≤ 45%

OR

- Syncope/resuscitation (mechanical ventilation)

Exclusion Criteria:

• Intracranial hemorrhage < 1 month ago
• Remaining life-expectancy < 6 month due to other cause
• Body mass index <15 OR > 40
• Clinical frailty score ≥6 before present worsening
• Severe lung disease (forced expiratory volume in 1 second OR diffusion capacity of the lungs for carbon monoxide < 25 of expected)
• Unsuitable for TAVI prior to screening