Supplementary Material for: Early Hemodynamic Changes during Head-Up Tilt Table Testing Can Predict a Neurocardiogenic Response in an African-American Patient Population
2015-12-16T00:00:00Z (GMT) by
Background: Head-up tilt table testing (HUTT) is time-consuming and associated with increased patient morbidity. Hemodynamic changes that occur during the early phase of HUTT may be predictive of neurocardiogenic syncope. Methods: A retrospective chart review was performed in 119 consecutive African Americans ( 57 ± 19) who underwent HUTT for evaluation of syncope of unknown etiology. Positive responses were defined as the development of symptoms linked with a systolic blood pressure (BP) <90 mm Hg, heart rate <50 b.p.m. or sinus arrest >3 s. Hemodynamic variables during the passive phase of HUTT were analyzed and results were then classified as a function of various predictors. Results: Sixty-two subjects (52%) had positive HUTT, and 57 (48%) had negative HUTT. Early changes in BP variables from baseline significantly predicted HUTT responses (p < 0.05). There was also a significant interaction between age and BP. An algorithm based on age and BP was developed which had positive and negative predictive values of 67.7 and 93%, respectively, with an accuracy of 79.8%. Conclusion: A novel algorithm utilizing the patients' age and changes in both systolic and diastolic BP during the early phase of HUTT enables the prediction of HUTT results without the use of vasoactive stimulation, allowing for rapid diagnosis, decreased patient morbidity and reduction in costs.