The progressive narrowing of the valve limits diastolic inflow into the left ventricle, eventually causing increased left atrial pressure, pulmonary congestion and pulmonary artery hypertension. This in turn leads to elevated right ventricular end diastolic pressure, increased right ventricular myocardial wall stress, Right Ventricular Hypertrophy and eventually Right Ventricular failure.
Any tachycardia, such as fast atrial fibrillation, is poorly tolerated because there will be diastolic filling time.
The patient continued to deteriorate with fast AF (160 beats/minute), a systolic blood pressure of 70 and agitation. Arterial blood gas showed a mixed respiratory and metabolic acidaemic and hypoxaemia. Noradrenaline was commenced and she was intubated and ventilated. She continued to deteriorate with escalating noradrenaline requirements.
