Therapeutic Hypothermia Reduces Peritoneal Dialysis Induced Myocardial Blood Flow Heterogeneity and Arrhythmia

Sanjay R Kharche; Sandrine Lemoine; Tanya Tamasi; Lisa Hur; Aaron So; Christopher W McIntyre

doi:10.3389/fmed.2021.700824

Therapeutic Hypothermia Reduces Peritoneal Dialysis Induced Myocardial Blood Flow Heterogeneity and Arrhythmia

Front Med (Lausanne). 2021 Jul 30:8:700824. doi: 10.3389/fmed.2021.700824. eCollection 2021.

Authors

Sanjay R Kharche^{1

2}, Sandrine Lemoine¹, Tanya Tamasi¹, Lisa Hur¹, Aaron So^{2

3}, Christopher W McIntyre^{1

2}

Affiliations

¹ Kidney Clinical Research Unit, Lawson's Health Research Institute, Victoria Hospital, London, ON, Canada.
² Department of Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada.
³ Imaging Program, Lawson Health Research Institute, London, ON, Canada.

Abstract

Background: Moderate therapeutic hypothermia (TH) is a well-recognized cardio-protective strategy. The instillation of fluid into the peritoneum provides an opportunity to deliver moderate hypothermia as primary prevention against cardiovascular events. We aimed to to investigate both cardiac perfusion consequences (overall blood flow and detailed assessment of perfusion heterogeneity) and subsequently simulate the associated arrhythmic risk for patients undergoing peritoneal dialysis (PD) induced TH. Methods: Patients underwent high resolution myocardial perfusion scanning using high resolution 256 slice CT scanning, at rest and with adenosine stress. The first visit using the patient's usual PD regimen, on the second visit the same regime was utilized but with cooled peritoneal dialysate at 32°C. Myocardial blood flow (MBF) was quantified from generated perfusion maps, reconstructed in 3D. MBF heterogeneity was assessed by fractal dimension (FD) measurement on the 3D left ventricular reconstruction. Arrhythmogenicity was quantified from a sophisticated computational simulation using a multi-scale human 3D ventricle wedge electrophysiological computational model. Results: We studied 7 PD patients, mean age of 60 ± 7 and mean vintage dialysis of 23.6 ± 17.6 months. There were no significant different in overall segmental MBF between normothermic condition (NT) and TH. MBF heterogeneity was significantly decreased (-14%, p = 0.03) at rest and after stress (-14%, p = 0.03) when cooling was applied. Computational simulation showed that TH allowed a normalization of action potential, QT duration and T wave. Conclusion: TH-PD results in moderate hypothermia leading to a reduction in perfusion heterogeneity and simulated risk of non-terminating malignant ventricular arrhythmias.

Keywords: arrhythmia; computational cardiology; computed tomography imaging; peritoneal dialysis; therapeutic hypothermia.