Dysphagia following transcatheter mitral valve-in-ring replacement complicated by neo-left ventricular outflow tract obstruction: a case report.

Neo-left ventricular outflow tract (LVOT) obstruction is a dreaded complication following transcatheter mitral valve replacement (TMVR). Dynamic LVOT obstruction has been reported to cause mechanical intravascular haemolysis due to red cell fragmentation. Intravascular haemolysis can result in a rare but well-described phenomenon in which patients experience dysphagia due to oesophageal spasm. This phenomenon is classically associated with paroxysmal nocturnal haemoglobinuria and has never been reported following TMVR. A 77-year-old female presented 8 days following TMVR with presyncope, dyspnoea, and severe dysphagia. Transthoracic echocardiography revealed neo-LVOT obstruction with trivial paravalvular mitral regurgitation. Doppler echocardiography revealed dynamic late-peaking LVOT obstruction with a peak gradient of 71 mmHg with Valsalva manoeuvre. Laboratory investigations demonstrated intravascular haemolytic anaemia. A barium swallow was performed revealing severe diffuse oesophageal spasm. Alternative causes of dysphagia were excluded, and a causal link between intravascular haemolysis and dysphagia was identified. Successful management of dynamic neo-LVOT obstruction, haemolytic anaemia, and dysphagia was achieved with beta blocker therapy and volume resuscitation. Serial echocardiography and barium swallow performed prior to discharge demonstrated resolution of LVOT obstruction and marked reduction in oesophageal spasm. To our knowledge, this is the first case report of TMVR complicated by reversible neo-LVOT obstruction with only trivial paravalvular regurgitation causing intravascular haemolysis and subsequent dysphagia. The management of dysphagia secondary to intravascular haemolysis due to neo-LVOT obstruction is challenging. This is because of the complex haemodynamic interplay between reduced oral intake, a high output state with anaemia, increased ventricular contractility, tachycardia, and worsening dynamic obstruction, all part of a vicious cycle (Summary figure).