TY - JOUR

T1 - Disrupted right ventricular force-frequency relationships in adults operated for ventricular septal defect as toddlers

T2 - abnormal peak force predicts peak oxygen uptake during exercise

AU - Heiberg, Johan

AU - Schmidt, Michael Rahbek

AU - Redington, Andrew

AU - Hjortdal, Vibeke Elisabeth

N1 - Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

PY - 2014/12/20

Y1 - 2014/12/20

N2 - 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. 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 workload 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. 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 < 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. 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.

AB - 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. 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 workload 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. 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 < 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. 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.

KW - Adolescent

KW - Adult

KW - Age Factors

KW - Child, Preschool

KW - Cohort Studies

KW - Denmark/epidemiology

KW - Exercise Test/trends

KW - Female

KW - Heart Septal Defects, Ventricular/diagnostic imaging

KW - Humans

KW - Male

KW - Oxygen Consumption/physiology

KW - Predictive Value of Tests

KW - Prospective Studies

KW - Ultrasonography

KW - Ventricular Dysfunction, Right/diagnostic imaging

KW - Young Adult

U2 - 10.1016/j.ijcard.2014.10.009

DO - 10.1016/j.ijcard.2014.10.009

M3 - Journal article

C2 - 25456699

VL - 177

SP - 918

EP - 924

JO - International Journal of Cardiology

JF - International Journal of Cardiology

SN - 0167-5273

IS - 3

ER -