Left Ventricular Non-compaction Cardiomyopathy and Polycystic Kidney Disease Revealed by Inappropriate Polycythemia: A Fortuitous Association? Case Report

We present the case of a patient with heart failure with reduced left ventricular (LV) ejection fraction, diagnosed in the first instance by echocardiography and further on by more accurate cardiac magnetic resonance imaging with LV non-compaction (LVNC). Blood tests showed high erythrocyte and hematocrit levels, inappropriate in this setting, whilst Janus Kinase 2V617F mutation was absent, erythropoietin level was slightly increased, and arterial O2 pressure level was normal. At the time of diagnosis, the patient had mild renal impairment, and abdominal echography revealed bilateral polycystic kidney disease (PKD). The patient had one son who fulfilled the echocardiographic criteria for LVNC and had bilateral renal cysts revealed by abdominal ultrasound. The genes responsible for autosomal dominant PKD (ADPKD) development are PKD1, on chromosome 16, coding for polycystin 1 and PKD2, on chromosome 4, coding for polycystin 2. There are some experimental data which suggest that polycystins might play an important role in cardiac development and hence PKD1 and PKD2 mutations may be involved in primary cardiomyopathies. These data could explain this particular association between LVNC and ADPKD. To date, there are only a few isolated cases reported, and only one shows this association in more than one member of the same family. Further genetic testing in the few reported cases would presumably elucidate whether this finding is the result of complex genetic synergy or just a simple coincidence.