Lead-Associated Superior Vena Cava Syndrome: Diagnostic Delay and the Role of Invasive Pressure Measurements.

Superior vena cava (SVC) syndrome is an uncommon complication of transvenous cardiac device leads. Diagnosis may be challenging due to gradually developing and nonspecific symptoms. Furthermore, anatomical imaging does not always reflect the hemodynamic significance of venous stenosis. We retrospectively evaluated seven patients treated for lead-associated SVC syndrome. Diagnostic delay was at least ten months in five patients. Computed tomography (CT) established the diagnosis in five patients, whereas invasive pressure measurement of the right atrium and SVC was performed in two patients for diagnostic certainty. In one patient, resting pressure measurements were non-diagnostic, while exercise provoked symptoms and an increase in SVC pressure. These findings highlight that SVC syndrome is a hemodynamical disorder rather than solely an anatomical stenosis. Invasive pressure measurements, including symptom provocation, may provide important diagnostic value.