OBJECTIVES: To evaluate the impact of systemic ventricular (SV) morphology on mechano-electrical interaction (MEI) and compare the results with clinical profiles in Fontan patients. BACKGROUND: Abnormal ventricular MEI causes systolic dysfunction of the right and left ventricles (RV, LV). METHODS: We evaluated serial changes (up to 15 years post-Fontan operation) in QRS duration (QRS-d, ms), catheterization-based hemodynamics and SV performance in 77 patients and compared them with 36 referents. RESULTS: Preoperative QRS-d was wider in the Fontan patients (86+/-14 vs. 64+/-9, p<0.001) and steadily increased for the next 15 years (107+/-25 vs. 85+/-9, p<0.001). QRS-d was wider in non-LV type SV patients than those with LV morphology (p<0.05) with a positive association with age at repair (p<0.001). SV contractility (Ees) improved in the RV and LV groups (p<0.05), during the next 10-year Ees, ventriculoarterial coupling (Ea/Ees) and ventricular efficiency (SW/PVA) were superior in the LV group. QRS-d and its long-term change correlated with the corresponding SV volume and change (p<0.01), respectively, while the immediate postoperative volume reduction did not result in the QRS-d shortening. QRS-d correlated with Ees, Ea/Ees, SW/PVA, and peak oxygen uptake (VO(2)) (p<0.001) and QRS-d was one of the main determinants of peak VO(2) (r=-0.48, p<0.001). CONCLUSIONS: SV morphology-associated wide QRS-d compromises the MEI as well as energetic properties long-term after the Fontan operation, especially in non-LV type patients.
OBJECTIVES: To evaluate the impact of systemic ventricular (SV) morphology on mechano-electrical interaction (MEI) and compare the results with clinical profiles in Fontan patients. BACKGROUND:Abnormal ventricular MEI causes systolic dysfunction of the right and left ventricles (RV, LV). METHODS: We evaluated serial changes (up to 15 years post-Fontan operation) in QRS duration (QRS-d, ms), catheterization-based hemodynamics and SV performance in 77 patients and compared them with 36 referents. RESULTS: Preoperative QRS-d was wider in the Fontan patients (86+/-14 vs. 64+/-9, p<0.001) and steadily increased for the next 15 years (107+/-25 vs. 85+/-9, p<0.001). QRS-d was wider in non-LV type SVpatients than those with LV morphology (p<0.05) with a positive association with age at repair (p<0.001). SV contractility (Ees) improved in the RV and LV groups (p<0.05), during the next 10-year Ees, ventriculoarterial coupling (Ea/Ees) and ventricular efficiency (SW/PVA) were superior in the LV group. QRS-d and its long-term change correlated with the corresponding SV volume and change (p<0.01), respectively, while the immediate postoperative volume reduction did not result in the QRS-d shortening. QRS-d correlated with Ees, Ea/Ees, SW/PVA, and peak oxygen uptake (VO(2)) (p<0.001) and QRS-d was one of the main determinants of peak VO(2) (r=-0.48, p<0.001). CONCLUSIONS: SV morphology-associated wide QRS-d compromises the MEI as well as energetic properties long-term after the Fontan operation, especially in non-LV type patients.