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Featured researches published by Yvan Mivelaz.


Cardiology in The Young | 2010

Considerations for Prenatal Counselling of Patients with Cardiac Rhabdomyomas based on their Cardiac and Neurologic Outcomes

Sabrina C. Degueldre; Priya Chockalingam; Yvan Mivelaz; Stefano Di Bernardo; Jean-Pierre Pfammatter; Catherine Barréa; Nicole Sekarski; Pierre-Yves Jeannet; Jean-Claude Fouron; Yvan Vial; Erik Jan Meijboom

Cardiac rhabdomyomas are benign cardiac tumours with few cardiac complications, but with a known association to tuberous sclerosis that affects the neurologic outcome of the patients. We have analysed the long-term cardiac and neurological outcomes of patients with cardiac rhabdomyomas in order to allow comprehensive prenatal counselling, basing our findings on the records of all patients seen prenatally and postnatally with an echocardiographic diagnosis of cardiac rhabdomyoma encountered from August, 1982, to September, 2007. We analysed factors such as the number and the location of the tumours to establish their association with a diagnosis of tuberous sclerosis, predicting the cardiac and neurologic outcomes for the patients.Cardiac complications include arrhythmias, obstruction of the ventricular outflow tracts, and secondary cardiogenic shock. Arrhythmias were encountered most often during the neonatal period, with supraventricular tachycardia being the commonest rhythm disturbance identified. No specific dimension or location of the cardiac rhabdomyomas predicted the disturbances of rhythm.The importance of the diagnosis of tuberous sclerosis is exemplified by the neurodevelopmental complications, with four-fifths of the patients showing epilepsy, and two-thirds having delayed development. The presence of multiple cardiac tumours suggested a higher risk of being affected by tuberous sclerosis. The tumours generally regress after birth, and cardiac-related problems are rare after the perinatal period. Tuberous sclerosis and the associated neurodevelopmental complications dominate the clinical picture, and should form an important aspect of the prenatal counselling of parents.


Archives of Cardiovascular Diseases | 2009

Advances in paediatric interventional cardiology since 2000

Sylvia Abadir; Georgia Sarquella-Brugada; Yvan Mivelaz; Nagib Dahdah; Joaquim Miro

Interventional paediatric and congenital cardiology is expanding at a rapid pace. Validated techniques (such as aortic or pulmonary valve dilatations and occlusion of persistent ductus arteriosus and atrial septal defects) are improving thanks to the use of smaller introducers and sheaths, low-profile balloons and novel devices. Moreover, catheter-based interventions have emerged as an attractive alternative to surgery in other fields: pulmonary valve replacement, balloon and stent implantation for native and recurrent coarctation, and percutaneous closure of ventricular septal defects. On the other hand, percutaneous interventions in the paediatric population may be limited by patient size or the anatomy of the defect. Hybrid approaches involving both cardiac interventionists and surgeons are being developed to overcome these limitations. Based on a better understanding of cardiac development, fetal cardiac interventions are being attempted in order to alter the history of severe obstructive lesions. Finally, some interventional procedures still carry a low success rate-for example, pulmonary vein stenosis, even with the use of conventional stents. Biodegradable stents and devices are being developed and may find an application in this setting as well as in others. The purpose of this review is to highlight the advances in paediatric interventional cardiology since the beginning of the third millennium.


European Journal of Cardio-Thoracic Surgery | 2008

Validation of two echocardiographic indexes to improve the diagnosis of complex coarctations

Yvan Mivelaz; Stefano Di Bernardo; Erik Jan Meijboom; Nicole Sekarski

OBJECTIVES Coarctation of the aorta is one of the most common congenital heart defects. Its diagnosis may be difficult in the presence of a patent ductus arteriosus, of other complex defects or of a poor echocardiographic window. We sought to demonstrate that the carotid-subclavian artery index (CSA index) and the isthmus-descending aorta ratio (I/D ratio), two recently described echocardiographic indexes, are effective in detection of isolated and complex aortic coarctations in children younger and older than 3 months of age. The CSA index is the ratio of the distal aortic arch diameter to the distance between the left carotid artery and the left subclavian artery. It is highly suggestive of a coarctation when it is <1.5. The I/D ratio defined as the diameter of the isthmus to the diameter of the descending aorta, suggests an aortic coarctation when it is less than 0.64. METHODS This is a retrospective cohort study in a tertiary care childrens hospital. Review of all echocardiograms in children aged 0-18 years with a diagnosis of coarctation seen at the authors institution between 1996 and 2006. An age- and sex-matched control group without coarctation was constituted. Offline echocardiographic measurements of the aortic arch were performed in order to calculate the CSA index and I/D ratio. RESULTS Sixty-eight patients were included in the coarctation group, 24 in the control group. Patients with coarctation had a significantly lower CSA index (0.84+/-0.39 vs 2.65+/-0.82, p<0.0001) and I/D ratio (0.58+/-0.18 vs 0.98+/-0.19, p<0.0001) than patients in the control group. Associated cardiac defects and age of the child did not significantly alter the CSA index or the I/D ratio. CONCLUSIONS A CSA index less than 1.5 is highly suggestive of coarctation independent of age and of the presence of other cardiac defects. I/D ratio alone is less specific than CSA alone at any age and for any associated cardiac lesion. The association of both indexes improves sensitivity and permits diagnosis of coarctation in all patients based solely on a bedside echocardiographic measurement.


Pediatric Rheumatology | 2014

Neonatal treatment of CINCA syndrome

Yan Paccaud; Gerald Berthet; Annette von Scheven-Gête; Bernard Vaudaux; Yvan Mivelaz; Michael Hofer; Matthias Roth-Kleiner

Chronic Infantile Neurological Cutaneous Articular (CINCA) syndrome, also called Neonatal Onset Multisystem Inflammatory Disease (NOMID) is a chronic disease with early onset affecting mainly the central nervous system, bones and joints and may lead to permanent damage. We report two preterm infants with severe CINCA syndrome treated by anti-interleukin-1 in the neonatal period, although, so far, no experience with this treatment in infants younger than three months of age has been reported. A review of the literature was performed with focus on treatment and neonatal features of CINCA syndrome.Case reportTwo cases suspected to have CINCA syndrome were put on treatment with anakinra in the early neonatal period due to severe clinical presentation. We observed a rapid and persistent decline of clinical signs and systemic inflammation and good drug tolerance. Diagnosis was confirmed in both cases by mutations in the NLRP3/CIAS1-gene coding for cryopyrin. As particular neonatal clinical signs polyhydramnios and endocardial overgrowth are to be mentioned.ConclusionWe strongly suggest that specific treatment targeting interleukin-1 activity should be started early. Being well tolerated, it can be introduced already in neonates presenting clinical signs of severe CINCA syndrome in order to rapidly control inflammation and to prevent life-long disability.


Swiss Medical Weekly | 2014

Evaluation of prenatal diagnosis of congenital heart disease in a regional controlled case study

Marie-Claude Rossier; Yvan Mivelaz; Marie-Claude Addor; Nicole Sekarski; Erik J. Meijboom; Yvan Vial

AIMS This study evaluated the evolution of the prenatal diagnosis of congenital heart disease (CHD) between 2003 and 2008 and its repercussion for the CHD prevalence rate at birth in a well-defined population (Canton of Vaud, Switzerland). METHODS AND RESULTS All 572 cases of CHD reported in the Eurocat Registry of Vaud-Switzerland between 1.5.2003 and 31.12.2008 were analysed and compared with the cases in our clinical database. CHD cases were divided into five different groups according to heart disease severity. The prenatal detection rates increased significantly between 2003 and 2008, with a mean detection rate of 25.2%. There was a significantly higher rate of prenatal diagnosis in the first four groups of CHD severity, with the highest detection rate (87.5%) found in the group with the most severe CHD (group 1). In this group, 85.7% of cases resulted in a termination of pregnancy, and there was a consequent 75% reduction in the prevalence of severe major cardiac malformation at birth. Detection rates were 66% in group 2, 68.6% in group 3, and the lowest in groups 4 and 5, with rates of 25.9% and 12.9%, respectively. CONCLUSION This study shows that the prenatal detection rate for CHD increased in a well-defined population over the study period. Prenatal diagnosis thus has had a major impact on patients with the most severe types of CHD and has resulted in a significant reduction in severe CHD at birth.


Ultrasound in Obstetrics & Gynecology | 2012

Population‐based review of tetralogy of Fallot with absent pulmonary valve: is prenatal diagnosis really associated with a poor prognosis?

Yvan Mivelaz; K. I. Lim; C. Templeton; A. I. Campbell; James E. Potts; George G.S. Sandor

Tetralogy of Fallot with absent pulmonary valve syndrome (TETAPV) is reported in obstetric literature to have an extremely poor prognosis. We sought to determine the clinical outcome associated with TETAPV and whether prenatal diagnosis confers a poor prognosis.


BMJ Open | 2017

Assessing the consequences of gestational diabetes mellitus on offspring’s cardiovascular health: MySweetHeart Cohort study protocol, Switzerland

Stefano Di Bernardo; Yvan Mivelaz; Adina Mihaela Epure; Yvan Vial; Umberto Simeoni; Pascal Bovet; Sandrine Estoppey Younes; Arnaud Chiolero; Nicole Sekarski

Introduction Gestational diabetes mellitus (GDM) is a state of glucose intolerance with onset during pregnancy. GDM carries prenatal and perinatal risks as well as long-term risks for the mother and her child. GDM may be involved in the foetal programming of long-term cardiovascular health. However, evidence is sparse and the effect of GDM on cardiovascular health is unknown. To address these issues, we will conduct MySweetHeart Cohort study. The objectives are to assess the effect of GDM on offspring’s cardiovascular health early in life by using surrogate markers of cardiovascular disease and atherosclerosis. Methods and analysis This is a cohort study of 100 offspring of women with GDM and 100 offspring of women without GDM. At inclusion, a baseline assessment of the mothers will be conducted through means of self-report questionnaires, a researcher-administrated interview, blood pressure and anthropometric measurements, and a maternal blood sampling. Between the 30th and 34th weeks of gestation, a foetal echography will be performed to assess the foetal cardiac structure and function, the fetomaternal circulation and the hepatic volume. At birth, maternal and neonatal characteristics will be assessed. An echocardiography will be performed to assess cardiac structure and function 2–7 days after birth; carotid intima-media thickness will be also measured to assess vascular structure. MySweetHeart Cohort is linked to MySweetHeart Trial (clinicaltrials.gov/ct2/show/NCT02890693), a randomised controlled trial assessing the effect of a multidimensional interdisciplinary lifestyle and psychosocial intervention to improve the cardiometabolic and mental health of women with GDM and their offspring. A long-term follow-up of children is planned. Ethics and dissemination Ethical approval has been obtained through the state Human Research Ethics Committee of the Canton de Vaud (study number 2016–00745). We aim to disseminate the findings through regional, national and international conferences and through peer-reviewed journals. Trial registration number ClinicalTrials.gov (clinicaltrials.gov/ct2/show/NCT02872974).


American Journal of Obstetrics and Gynecology | 2010

Ultrasonographic diagnosis of delayed atrioventricular conduction during fetal life: a reliability study

Yvan Mivelaz; Marie Josée Raboisson; Sylvia Abadir; Georgia Sarquella-Brugada; Anne Fournier; Jean-Claude Fouron

OBJECTIVE The objective of the study was to evaluate the reliability of the 2 most commonly used ultrasonographic approaches for monitoring fetal atrioventricular conduction time (AVCT): (1) superior vena cava/ascending aorta (SVC/AA), and (2) left ventricular inflow/outflow tract (LVI/O) Doppler recordings. STUDY DESIGN Echographic studies from fetuses followed up for first-degree atrioventricular block (AVB-1) between 1998 and 2008 were reviewed. The ability to identify atrial contractions in the same fetuses by the SVC/AA and LVI/O approaches was analyzed. RESULTS Sixty-six studies of 13 fetuses with AVB-1 were available. Atrial contractions were visible in all SVC/AA studies. With the LVI/O approach, atrial contractions could not be identified in 26 studies (39%). AVCT delay was significantly greater in the nonidentifiable compared with the identifiable atrial contraction group (P < .001). Differences in heart rate and gestational age were not significant. CONCLUSION The LVI/O is unsuitable for prenatal screening of conduction system anomalies.


European Journal of Pediatrics | 2007

A noninvasive diagnostic tool to differentiate myocarditis from myocardial infarction: late gadolinium enhanced cardiac magnetic resonance

Yvan Mivelaz; Nicole Sekarski; Salah D. Qanadli; Erik Jan Meijboom; Stefano Di Bernardo

Studies in adults have shown that late gadolinium enhanced cardiac magnetic resonance is a safe and noninvasive diagnostic tool which allows one to differentiate myocardial infarction from myocarditis. We believe that it may also be highly useful in the paediatric population for the same purpose.


Journal of Hypertension | 2016

Feasibility and reliability of carotid intima-media thickness measurements in nonsedated infants.

Yvan Mivelaz; Stefano Di Bernardo; Tatiana Boulos Ksontini; Milan Prsa; Yvan Vial; Arnaud Chiolero; Nicole Sekarski

Introduction: Carotid intima–media thickness (CIMT) is a surrogate marker for atherosclerosis. It is increased in adolescents and young adults at risk for future cardiovascular disease. However, it remains unclear if it can be considered as a surrogate marker for atherosclerosis in infancy as very few studies have been performed in infants. Objectives: Our objective was to assess the feasibility and interobserver reproducibility of CIMT measurement in nonsedated infants. Methods: We measured CIMT in 81 infants less than 1 year of age. Repeated measurements were obtained by a second observer in 24 children. The analysis was performed with semiautomated edge detection software. Measurements with over 95% edge detection over a length of 1 cm were considered as valid. We further compared the measurements using the semiautomated method with measurements using the manual electronic caliper method in a subgroup of 10 infants. Results: Carotid ultrasound recordings and intima–media thickness measurements were obtained in 79% of infants (n = 64). Mean CIMT of the 64 infants measured by the first observer was 0.44 mm (SD: 0.04). In the 24 participants with measurements by two observers, the mean interobserver difference was 0.001 mm (SD: 0.026). The interobserver coefficient of variation was 5.9%. CIMT measurements obtained with the manual method (mean: 0.35; range: 0.29–0.39) were slightly lower than measurements obtained with the semiautomated method (mean: 0.38; range: 0.32–0.44). Measurements with both methods were highly correlated (r: 0.87). Conclusion: Measurement of CIMT in nonsedated infants less than 1 year of age is feasible in the majority of infants with good interobserver variability.

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Yvan Vial

University of Lausanne

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Milan Prsa

University of Lausanne

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George G.S. Sandor

University of British Columbia

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James E. Potts

University of British Columbia

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