Longitudinal characterization of clinically relevant haemodynamics in conscious Ossabaw pigs with HFpEF

Abstract

Abstract Background The constantly growing population of patients suffering from heart failure with preserved ejection fraction (HFpEF) is one of the largest unmet needs in cardiovascular medicine and translational animal models are important for identification and profiling of novel therapeutic approaches. Large animal models have shown that chronic cardiac pressure overload by aortic banding (AoB), when combined with a Western diet leads to left ventricular hypertrophy, diastolic dysfunction and metabolic syndrome in the Ossabaw pig, reflecting important features of human HFpEF characteristics. However, the requirement of invasive diagnostics under anaesthesia often limits the ability to monitor disease development continuously and compromises the results. Therefore, current disease models lack the temporal progression of clinically relevant HFpEF parameters like the left ventricular end diastolic pressure (LVEDP) and time constant of left ventricular relaxation (Tau). Purpose We aim to non-invasively investigate disease progression in Ossabaw pigs exhibiting a cardiometabolic HFpEF phenotype. The longitudinal assessment of LVEDP, Tau and heart rate (HR) should identify a time window to test novel therapeutics. Methods Naive, female Ossabaw pigs were instrumented with telemetric devices followed by AoB to induce chronic cardiac pressure overload. The wound healing and acclimatization period was followed by the start of a Western diet feeding regime to mimic components of the metabolic syndrome. Disease progression was characterized over 9 months by monthly telemetric recordings of LVEDP, Tau and HR and compared to a control (Ctrl) measurement in healthy animals. All animal studies followed the `Principles of laboratory animal care'. Results Compared to Ctrl the LVEDP is significantly elevated already 1 month (+8.90±0.4 mmHg) after AoB and further increases over time until 8 months (+18.80±0.4 mmHg) post AoB. Significant elevations in Tau are evident 4 months (+1.61±0.4 ms) post AoB. After 1 month the HR is significantly elevated (+13.90±0.7 bpm) but tends to normalize between 5 to 7 months post AoB. After AoB a maximal relative increase in LVEDP (+5.12±0.4 mmHg), Tau (+5.04±0.4 ms) and HR (+16.90±0.7 bpm) can be observed after 8 months. Conclusions We present long term haemodynamic changes over time in a translational in vivo model for HFpEF in Ossabaw pigs with high temporal resolution. For the first time elevations in key parameters allow to set a time point where HFpEF characteristics are evident, and a drug testing regime could be started. The opportunity to non-invasively and longitudinally follow on LVEDP, Tau and HR will be a clear benefit in the development of novel treatment options for HFpEF. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Bayer AG, Wuppertal