Disrupted right ventricular force-frequency relationships in adults operated for ventricular septal defect as toddlers: Abnormal peak force predicts peak oxygen uptake during exercise

作者：Heiberg Johan^*; Schmidt Michael Rahbek; Redington Andrew; Hjortdal Vibeke Elisabeth

来源：International Journal of Cardiology, 2014, 177(3): 918-924.

DOI：10.1016/j.ijcard.2014.10.009

• Congenital heart disease
• Ventricular septal defect
• Force-frequency response
• Long-term follow-up

Recent studies have shown markedly reduced functional capacity in long-term survivors of ventricular septal defect (VSD), and in order to explore possible mechanisms, we performed non-invasive assessment of ventricular force-frequency relationships during exercise in adults operated for VSD in early childhood. %26lt;br%26gt;We conducted a prospective study at a tertiary referral center. Patients (n = 23) and healthy controls (n = 20) underwent continuous Doppler-echocardiographic imaging during supine bicycle ergometry. The cycling work-load was individually and manually incremented during the test session in response to heart rate. The heart was imaged in an apical 4-chamber view, and color-coded myocardial velocities were recorded. Post hoc, peak systolic velocity and isovolumetric acceleration (IVA) were blindly determined in the basal ventricular segments. %26lt;br%26gt;VSD-operated patients differed markedly in all right ventricular endpoints compared with controls. IVA was lower prior to the test, 70 +/- 30 cm/s(2) vs. 150 +/- 60 cm/s(2) among controls, and during the entire test session ending at a heart rate of 160 beats/min; 140 +/- 50 cm/s(2) vs. 300 +/- 30 cm/s(2), p %26lt; 0.01 at both points. A similar pattern was revealed in terms of peak right ventricular systolic velocity. Left ventricular and septal measurements showed a similar, although less significant, tendency with a clearly lower left ventricular optimum heart rate among patients: 140 beats/min vs. 154 beats/min among controls. In the diseased cohort biventricular force-frequency relationships were directly correlated to peak oxygen uptake. %26lt;br%26gt;VSD repair in early childhood is associated with disruption of the right ventricular force-frequency relationship, which may contribute to the previously observed reduction in functional capacity.

• 出版日期2014-12-20