Integrative Cardiovascular and Neurophysiological Assessment of Unexplained Syncope: A Mechanism-Based Approach to Transient Loss of Consciousness
DOI:
https://doi.org/10.64784/305Palabras clave:
unexplained syncope, transient loss of consciousness, cardiovascular monitoring, implantable loop recorder, autonomic dysfunction, tilt-table testing, cerebral hypoperfusion, electroencephalography, epilepsy, psychogenic pseudosyncope, differential diagnosis, arrhythmiasResumen
Unexplained syncope remains a major diagnostic challenge because transient loss of consciousness may result from cardiovascular, autonomic, neurological, or functional mechanisms that are not always identified during the initial clinical evaluation. This study analyzed the diagnostic value of integrating cardiovascular and neurophysiological assessment in recurrent syncope of uncertain origin through a structured integrative review based on the Scientific Method. Evidence from clinical guidelines, consensus statements, systematic reviews, meta-analyses, and relevant diagnostic studies was examined, with particular emphasis on prolonged electrocardiographic monitoring, implantable loop recorders, orthostatic blood pressure assessment, tilt-table testing, autonomic evaluation, electroencephalography, and the differential diagnosis of epileptic seizures and psychogenic pseudosyncope. The analyzed findings showed that prolonged cardiac monitoring increases the probability of identifying intermittent arrhythmias, with bradyarrhythmias representing an important documented mechanism in recurrent unexplained episodes. Diagnostic yield increased progressively with longer monitoring periods, reaching its highest values with implantable loop recorders. Hemodynamic analysis also demonstrated distinct patterns among vasovagal syncope, classical orthostatic hypotension, and psychogenic pseudosyncope. Clinical history remained essential for distinguishing syncope from epilepsy, particularly when considering prodromal manifestations, tongue injury, postictal confusion, diaphoresis, posture, and recovery characteristics. Routine electroencephalography showed limited etiological yield when neurological suspicion was absent, supporting its selective use. Overall, the findings indicate that the most informative diagnostic strategy is not based on the indiscriminate accumulation of tests but on the sequential integration of clinical, cardiovascular, autonomic, and neurophysiological information. A multidisciplinary, mechanism-oriented approach improves etiological characterization, reduces diagnostic uncertainty, and provides a stronger basis for clinical decision-making in patients with recurrent unexplained transient loss of consciousness.
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