Dynamic changes in right ventricular pressures during haemodialysis recorded with an implantable haemodynamic monitor.

BACKGROUND: Intermittent and chronic volume overload contributes to the development of cardiovascular disease in patients on maintenance haemodialysis (HD). Continuous monitoring of central haemodynamic parameters may provide valuable information to improve volume control, particularly in patients with left ventricular dysfunction. METHODS: Five patients on HD, age 53-76 years, with systolic and/or diastolic dysfunction (EF 20-50%) received an implantable haemodynamic monitor (IHM) (Chronicle model 9520, Medtronic). The IHM consists of a memory device implanted subcutaneously and a transveneous right ventricular (RV) lead carrying a pressure sensor. It continuously records heart rate, RV systolic (RVSP) and diastolic pressures (RVDP), RV dP/dt and an estimate of pulmonary artery diastolic pressure (ePAD). Continuous haemodynamic profiles were recorded in all patients. RESULTS: During dialysis RVSP and ePAD dropped by a mean of 39 and 50%, respectively. RVDP decreased by 6.6 mmHg. The lowest pressures occurred during the first 90 min of dialysis and were partly restored at the end of the procedure. Long-term haemodynamic monitoring unmasked severe volume overload in one patient, when dry weight was kept stable despite a decrease in lean body mass. In another patient with recurrent dyspnea after dialysis, paroxysmal atrial fibrillation, regularly occurring during dialysis, was identified as the cause of symptoms. CONCLUSION: The implanted haemodynamic monitor was a sensitive indicator for changes in volume load. Continuous haemodynamic monitoring may offer a valuable tool to improve volume management in dialysis patients with left ventricular dysfunction.