Comparative Noninvasive Measurement of Cardiac Output Based on the Inert Gas Rebreathing Method (Innocor®) and MRI in Patients with Univentricular Hearts
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There are many complex cardiac malformations that are characterized by a functionally univentricular physiology. Staged surgical repair according to the Fontan principle separates the systemic and pulmonary circulations by connecting the systemic venous return to the pulmonary arteries. However, long-term follow-up studies demonstrate a gradual deterioration of cardiac function, particularly from the second or third decade. Noninvasive evaluation of the cardiac function is, therefore, important in the follow-up of these patients. The cardiac index (CI) is a reliable hemodynamic parameter and represents an important marker of cardiac function. We compared CI values determined by cardiac MRI (CMRI) with values obtained by noninvasive inert gas rebreathing (IGR; Innocor® system). Sixteen patients (age range: 7.2–32.7 years) with functionally univentricular hearts (UVH) following total cavopulmonary connection (TCPC) were compared with 12 healthy subjects (age range: 8.5–18.6 years). The standard treadmill protocol of the German Society of Pediatric Cardiology was used for exercise testing. CI was determined at rest and at two standardized submaximal exercise levels. In all subjects, CI increased under exercise conditions, but the values were significantly lower in patients with UVH. There was no significant difference between patients with UVH and predominantly right- or left-ventricular morphology. In comparison with CMRI measurements, the CI values obtained by the IGR method tended to be lower, with a mean difference of 1.02 l/min/m2. Noninvasive measurement of CI with the IGR method is feasible at rest and during exercise, and appears to be suited for routine determination of CI in patients with UVH following TCPC.
KeywordsCardiac output Inert gas rebreathing method Innocor® MRI Magnetic resonance imaging Functional univentricular heart
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest.
The study protocol was approved by the local ethics committee of the University Hospital Tuebingen.
- 1.Navarro-Aguilar V, Flors L, Calvillo P, Merlos P, Buendía F, Igual B, Melero-Ferrer J, Soriano JR, Leiva-Salinas C (2015) Fontan procedure: imaging of normal post-surgical anatomy and the spectrum of cardiac and extracardiac complications. Clin Radiol 70(3):295–303. https://doi.org/10.1016/j.crad.2014.10.005 CrossRefPubMedGoogle Scholar
- 5.Robbers-Visser D, Kapusta L, van Osch-Gevers L, Strengers JLM, Boersma E, de Rijke YB, Boomsma F, Bogers AJJC, Helbing WA (2009) Clinical outcome 5 to 18 years after the Fontan operation performed on children younger than 5 years. J Thorac Cardiovasc Surg 138(1):89–95. https://doi.org/10.1016/j.jtcvs.2008.12.027 CrossRefPubMedGoogle Scholar
- 7.Trinkmann F, Berger M, Doesch C, Sampels M, Papavassiliu T, Grüttner J, Borggrefe M, Kaden JJ, Saur J (2012) Überblick der nicht-invasiven Bestimmung des Herzzeitvolumens—Vergleich neuer Methoden mit dem Goldstandard kardiale Magnetresonanztomografie. Fortschr Röntgenstr 184(02):TNE09. https://doi.org/10.1055/s-0031-1300910 CrossRefGoogle Scholar
- 9.Saur J, Fluechter S, Trinkmann F, Papavassiliu T, Schoenberg S, Weissmann J, Haghi D, Borggrefe M, Kaden JJ (2009) Noninvasive determination of cardiac output by the inert-gas-rebreathing method–comparison with cardiovascular magnetic resonance imaging. Cardiology 114(4):247–254. https://doi.org/10.1159/000232407 CrossRefPubMedGoogle Scholar
- 11.Agostoni P, Cattadori G, Apostolo A, Contini M, Palermo P, Marenzi G, Wasserman K (2005) Noninvasive measurement of cardiac output during exercise by inert gas rebreathing technique: a new tool for heart failure evaluation. J Am Coll Cardiol 46(9):1779–1781. https://doi.org/10.1016/j.jacc.2005.08.005 CrossRefPubMedGoogle Scholar
- 16.Hauser J, Michel-Behnke I, Zervan K, Pees C (2011) Noninvasive measurement of atrial contribution to the cardiac output in children and adolescents with congenital complete atrioventricular block treated with dual-chamber pacemakers. Am J Cardiol 107(1):92–95. https://doi.org/10.1016/j.amjcard.2010.08.050 CrossRefPubMedGoogle Scholar
- 17.Wiegand G, Binder W, Ulmer H, Kaulitz R, Riethmueller J, Hofbeck M (2012) Noninvasive cardiac output measurement at rest and during exercise in pediatric patients after interventional or surgical atrial septal defect closure. Pediatr Cardiol 33(7):1109–1114. https://doi.org/10.1007/s00246-012-0239-2 CrossRefPubMedGoogle Scholar
- 20.Lang CC, Karlin P, Haythe J, Tsao L, Mancini DM (2007) Ease of noninvasive measurement of cardiac output coupled with peak VO2 determination at rest and during exercise in patients with heart failure. Am J Cardiol 99(3):404–405. https://doi.org/10.1016/j.amjcard.2006.08.047 CrossRefPubMedGoogle Scholar
- 23.Bossers SSM, Kapusta L, Kuipers IM, van Iperen G, Moelker A, Kroft LJM, Romeih S, de Rijke Y, ten Harkel ADJ, Helbing WA (2015) Ventricular function and cardiac reserve in contemporary Fontan patients. Int J Cardiol 196(0):73–80. https://doi.org/10.1016/j.ijcard.2015.05.181 CrossRefPubMedGoogle Scholar
- 24.Whitehead KK, Gillespie MJ, Harris MA, Fogel MA, Rome JJ (2009) Noninvasive quantification of systemic-to-pulmonary collateral flow: a major source of inefficiency in patients with superior cavopulmonary connections. Circ Cardiovasc Imag 2(5):405–411. https://doi.org/10.1161/circimaging.108.832113 CrossRefGoogle Scholar
- 25.Bossers SS, Cibis M, Gijsen FJ, Schokking M, Strengers JL, Verhaart RF, Moelker A, Wentzel JJ, Helbing WA (2014) Computational fluid dynamics in Fontan patients to evaluate power loss during simulated exercise. Heart 100(9):696–701. https://doi.org/10.1136/heartjnl-2013-304969 CrossRefPubMedGoogle Scholar
- 27.Ohuchi H, Yasuda K, Hasegawa S, Miyazaki A, Takamuro M, Yamada O, Ono Y, Uemura H, Yagihara T, Echigo S (2001) Influence of ventricular morphology on aerobic exercise capacity in patients after the Fontan operation. J Am Coll Cardiol 37(7):1967–1974. https://doi.org/10.1016/S0735-1097(01)01266-9 CrossRefPubMedGoogle Scholar
- 29.Saur J, Trinkmann F, Doesch C, Scherhag A, Brade J, Schoenberg SO, Borggrefe M, Kaden JJ, Papavassiliu T (2010) The impact of pulmonary disease on noninvasive measurement of cardiac output by the inert gas rebreathing method. Lung 188(5):433–440. https://doi.org/10.1007/s00408-010-9257-0 CrossRefPubMedGoogle Scholar