Arrhythmias in Pulmonary Hypertension

Cardiac arrhythmias are common in patients with pulmonary arterial hypertension (PAH) due to structural and electrical remodelling of the right heart, and are associated with adverse clinical outcomes. This study investigated the prevalence and clinical significance of conduction abnormalities and arrhythmias in idiopathic PAH (IPAH), using resting electrocardiograms (ECGs) and implantable cardiac monitors (ICMs), and explored the arrhythmogenic substrate using invasive and non-invasive cardiac mapping techniques. ECG analysis revealed a significantly higher prevalence of first-degree atrioventricular (AV) block and bundle branch block in IPAH patients compared to matched controls. Continuous monitoring with ICMs showed that the incidence of arrhythmias in IPAH was higher than previously recognized and comparable to that of patients with standard indications for rhythm surveillance. The presence of conduction disease or arrhythmia was independently associated with worse survival and reduced functional capacity, regardless of pulmonary haemodynamic status. Right atrial enlargement was identified as a key correlate of both conduction disturbances and arrhythmia incidence, suggesting a possible role for targeted screening in this subgroup. Invasive and non-invasive electrophysiological studies further demonstrated that right atrial dilation is linked to slower conduction velocity, prolonged repolarization, and increased AV nodal refractoriness, offering mechanistic insights into arrhythmia development. These findings underscore the need for future research into the benefit of prophylactic arrhythmia screening and intervention in IPAH patients with right atrial dilation, and the role of risk factor modification. Such studies could lead to more effective, personalized management strategies for PH patients.

Name dc:type.qualificationname

Doctor of Medicine (MD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2025

Author dc:creator

• Reddy, SATHINENI

Advisors dc:contributor.advisor

• Toshner, mark
• Martin, claire

• Heart rhythm
• implantable cardiac devices
• Pulmonary vascular disease

Licence

• https://www.repository.cam.ac.uk/bitstreams/7f2767fd-05e5-4845-b0cb-bee396a6b6fb/download
• http://purl.org/NET/rdflicense/allrightsreserved

Language dc:language

eng

DOI dc:identifier.doi

https://doi.org/10.17863/CAM.130429

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/403519