AIMS AND OBJECTIVES: For patients with a recurring and elusive heart disorder, participation is challenging because of the need for care across the healthcare system. This paper describes how patients with supraventricular tachycardia (SVT) experience participation in their healthcare encounters. METHODOLOGICAL DESIGN: A descriptive phenomenological design in line with the reflective lifeworld research approach was used. Interviews were conducted with 17 patients, and the analysis was carried out to analyse participation as it evolved from the initial healthcare encounter through various phases of illness and treatment. FINDINGS: Patient participation in the context of SVT is commonly experienced as limited, inconsistent, and fragmented. These shortcomings contributed to feelings of existential insecurity and led patients to repeatedly seek care. Patients described a lack of continuity, passive or dismissive responses from healthcare professionals, and not being taken seriously-factors that increased their vulnerability and disrupted daily life. Overall, the findings underscore the need to recognise patients' lived experiences and to support their active involvement in diagnostic processes and treatment decisions. CONCLUSIONS: Patients with SVT continue to face challenges in participation in their care due to fragmented care pathways and repeated encounters with multiple healthcare providers. The study underscores the importance of validating intermittent symptoms, providing clear information, and ensuring continuity to support meaningful participation. Improved education for healthcare professionals-focusing on trust-building, communication, and managing uncertainty-is essential. Further research should develop and evaluate interventions that enhance trust and address the informational and existential dimensions of living with SVT.