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Int J Cardiol ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33571563


BACKGROUND: Pregnant women with repaired tetralogy of Fallot (rTOF) are at increased risk of adverse outcomes. Although pre-pregnancy pulmonary valve replacement (PVR) may be considered in some women to attenuate risk, published data to support this practice are lacking. Our objective was to explore the impact of pre-pregnancy PVR on pregnancy outcomes in rTOF. METHODS: Women with rTOF and cardiovascular magnetic resonance imaging (CMR) before and after pregnancy were included if CMR studies were completed within 3 years of pregnancy. Subjects were compared according to presence (+) or absence (-) of PVR at pre-pregnancy CMR. Pregnancy outcomes (cardiovascular, obstetric, and fetal/neonatal) were documented. RESULTS: Of the 29 study women identified, 7 were PVR+ and 22 were PVR-. Post-pregnancy, the PVR- group demonstrated interval increase in indexed right ventricular end-diastolic volumes (RVEDVi) (157 ± 28 versus 166 ± 33 ml/m2, p = 0.003) and end-systolic volumes (RVESVi) (82 ± 17 versus 89 ± 20 ml/m2, p = 0.003) as compared with pre-pregnancy, but no significant change in RV ejection fraction, RV mass, or left ventricular measurements. In the PVR+ group, there were no interval changes in RV measurements pre-versus post pregnancy. Interval rate of change in RVESVi of PVR- exceeded PVR+ women (+3.7 ± 5.0 versus -2.2 ± 5.0 ml/m2/year, p = 0.03). Pregnancy outcomes did not differ in PVR+ versus PVR- women. CONCLUSIONS: Pregnancy outcomes did not differ according to PVR status in our cohort. While RV volumes remained unchanged in PVR+ women, interval RV dilation was observed in PVR- women. Additional study of a larger population with longer follow-up may further inform clinical practice regarding pre-pregnancy PVR.

Heart ; 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32748799


OBJECTIVES: Although a life-preserving surgery for children with single ventricle physiology, the Fontan palliation is associated with striking morbidity and mortality with advancing age. Our primary objective was to evaluate the impact of non-invasive, external, thoraco-abdominal ventilation on pulmonary blood flow (PBF) and cardiac output (CO) as measured by cardiovascular magnetic resonance (CMR) imaging in adult Fontan subjects. METHODS: Adults with a dominant left ventricle post-Fontan palliation (lateral tunnel or extracardiac connections) and healthy controls matched by sex and age were studied. We evaluated vascular flows using phase-contrast CMR imaging during unassisted breathing, negative pressure ventilation (NPV) and biphasic ventilation (BPV). Measurements were made within target vessels (aorta, pulmonary arteries, vena cavae and Fontan circuit) at baseline and during each ventilation mode. RESULTS: Ten Fontan subjects (50% male, 24.5 years (IQR 20.8-34.0)) and 10 matched controls were studied. Changes in PBF and CO, respectively, were greater following BPV as compared with NPV. In subjects during NPV, PBF increased by 8% (Δ0.20 L/min/m2 (0.10-0.53), p=0.011) while CO did not change significantly (Δ0.17 L/min/m2 (-0.11-0.23), p=0.432); during BPV, PBF increased by 25% (Δ0.61 L/min/m2 (0.20-0.84), p=0.002) and CO increased by 16% (Δ0.47 L/min/m2 (0.21-0.71), p=0.010). Following BPV, change in PBF and CO were both significantly higher in subjects versus controls (0.61 L/min/m2 (0.2-0.84) vs -0.27 L/min/m2 (-0.55-0.13), p=0.001; and 0.47 L/min/m2 (0.21-0.71) vs 0.07 L/min/m2 (-0.47-0.33), p=0.034, respectively). CONCLUSION: External ventilation acutely augments PBF and CO in adult Fontan subjects. Confirmation of these findings in larger populations with longer duration of ventilation and extended follow-up will be required to determine sustainability of haemodynamic effects.

J Cardiovasc Magn Reson ; 20(1): 19, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29544519


BACKGROUND: Calculation of cardiovascular magnetic resonance (CMR) extracellular volume (ECV) requires input of hematocrit, which may not be readily available. The purpose of this study was to evaluate the diagnostic accuracy of ECV calculated using various noninvasive measures of hematocrit compared to ECV calculated with input of laboratory hematocrit as the reference standard. METHODS: One hundred twenty three subjects (47.7 ± 14.1 years; 42% male) were prospectively recruited for CMR T1 mapping between August 2016 and April 2017. Laboratory hematocrit was assessed by venipuncture. Noninvasive hematocrit was assessed with a point-of-care (POC) device (Pronto-7® Pulse CO-Oximeter®, Masimo Personal Health, Irvine, California, USA) and by synthetic derivation based on the relationship with blood pool T1 values. Left ventricular ECV was calculated with input of laboratory hematocrit (Lab-ECV), POC hematocrit (POC-ECV), and synthetic hematocrit (synthetic-ECV), respectively. Statistical analysis included Wilcoxon signed-rank test, Bland-Altman analysis, receiver-operating curve analysis and intra-class correlation (ICC). RESULTS: There was no significant difference between Lab-ECV and POC-ECV (27.1 ± 4.7% vs. 27.3 ± 4.8%, p = 0.106), with minimal bias and modest precision (bias - 0.18%, 95%CI [- 2.85, 2.49]). There was no significant difference between Lab-ECV and synthetic-ECV (26.7 ± 4.4% vs. 26.5 ± 4.3%, p = 0.084) in subjects imaged at 1.5 T, although bias was slightly higher and limits of agreement were wider (bias 0.23%, 95%CI [- 2.82, 3.27]). For discrimination of abnormal Lab-ECV ≥30%, POC-ECV had good diagnostic performance (sensitivity 85%, specificity 96%, accuracy 94%, and AUC 0.902) and synthetic-ECV had moderate diagnostic performance (sensitivity 71%, specificity 98%, accuracy 93%, and AUC 0.849). POC-ECV had excellent test-retest (ICC 0.994, 95%CI[0.987, 0.997]) and inter-observer agreement (ICC 0.974, 95%CI[0.929, 0.991]). CONCLUSIONS: Myocardial ECV can be accurately and reproducibly calculated with input of hematocrit measured using a noninvasive POC device, potentially overcoming an important barrier to implementation of ECV. Further evaluation of synthetic ECV is required prior to clinical implementation.

Cardiopatias/diagnóstico por imagem , Hematócrito/instrumentação , Imagem Cinética por Ressonância Magnética , Oximetria/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Adulto , Estudos de Casos e Controles , Desenho de Equipamento , Feminino , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes