Parkinson’s Disease and the Cardiac Cycle: A Rapid Literature Review and Case Series

The relationship between cardiac function and Parkinson’s Disease (PD) remains poorly understood. This review aims to summarize current literature on the cardiac cycle in PD patients, followed by a case series to detail the cardiac cycle timing intervals in this population.

Methods: A comprehensive literature search was conducted using terms such as (“Cardiac cycle” OR “echocardiography” OR “LVET” OR “IVCT” OR “IVRT” OR “LVEF” OR “Systolic Dysfunction” OR “Diastolic Dysfunction”) AND (“Parkinson’s Disease”), yielding 514 studies, with 19 selected for inclusion.

Results: The review highlighted studies that explored the effects of medication, autonomic dysfunction, and resting-state factors on the cardiac cycle in PD. While findings were inconsistent, evidence suggested that PD patients experience some degree of systolic dysfunction, with recent studies pointing to subclinical systolic dysfunction. In the case series, 13 PD participants provided cardiac data over 6 weeks, showing stable heart rate (67–71 bpm) and consistent cardiac parameters week-to-week: systolic time interval at 332–348 ms, isovolumic relaxation time at 92–96 ms, and isovolumic contraction time at 34–36 ms.

Conclusion: These timing intervals offer important normative data for PD patients, though further research is needed to fully understand cardiac cycle variations in this population.