Supervisors info:
Αθανάσιος Πρωτογέρου, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ, Επιβλέπων
Αντώνιος Χατζηγεωργίου, Αναπληρωτής Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Θεόδωρος Παπαϊωάννου, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Summary:
Background: Circulatory Power (CircP) enhances the prognostic value of cardiopulmonary exercise test (CPET) in a wide range of cardiovascular and pulmonary diseases; however, it has been investigated only in specific ones. The differences in CircP between normotensive and hypertensive individuals, as well as its association with aortic stiffness (carotid-femoral pulse wave velocity, cfPWV), pressure wave reflections (augmentation index, AIx) and carotid remodeling (intima-media thickness, IMT), has not been investigated so far. To test the hypotheses that CircP is higher in normotensive than in hypertensive individuals and, that CircP will be significantly associated with carotid remodeling.
Method: Under standardized laboratory conditions using the Sphygmocor AtCor device having a built-in algorithm for pulse wave analysis, cfPWV and AIx were measured; left/ right common carotid IMT were measured by ultrasound. A separated day CPET was performed and CircP was calculated as the product of peak oxygen consumption (VO2peak; mL O2·kg−1 ·min−1), derived from gas analyzer, and peak systolic blood pressure (peak SBP; mmHg), derived from another cuff-based recording device. All individuals conducted an individualized incremental breath-by-breath protocol on cycle ergometer. Linear regression analysis and 2 independent samples t-test were performed.
Results: Analysis was performed in 34 consecutive individuals (aged 54,63±12,7; 67% men; 79%hypertensive; 88% dyslipidemic; 18% with type 1 diabetes; 3% patients with type 2 diabetes); normotensive had higher units of CircP than hypertensive (4333±1920 versus 3193±797). CircP was found to depend considerably on age (0.004, p<0.01), body mass index (0.028, p<0.05). AIx (-0.005, p<0,01), left and right IMT (-0.015, p<0.05; -0.004, p<0.01) were found to have significant correlation with CircP.
Conclusion: CircP is higher in normotensive than in hypertensive individuals, and it is significantly associated with pressure wave reflections and carotid remodeling.
Keywords:
Circulatory power, Cardiopulmonary exercise test, Hypertension, Pulse wave analysis, Carotid remodeling
