Marie Cambon-Viala1, Hilla Gerard1, Karine Nguyen2, Pascale Richard3, Flavie Ader3, Jean-François Pruny4, Erwan Donal5, Jean-Christophe Eicher6, Olivier Huttin7, Christine Selton-Suty7, Pascale Raud-Raynier8, Guillaume Jondeau9, Nicolas Mansencal10, Caroline Sawka11, Anne-Claire Casalta1, Nicolas Michel1, Valeria Donghi1, Hélène Martel1, Laurence Faivre11, Philippe Charron12, Gilbert Habib13. 1. Cardiology Department, APHM, La Timone Hospital, Marseille, France. 2. Département de génétique médicale, APHM, Hôpital d'enfants de la Timone, Marseille, France; Aix Marseille University, INSERM, Marseille Medical Genetics, Faculté de Médecine, France. 3. APHP, Functional Unit of Cardiogénétique et Myogénétique, Service de Biochimie Métabolique, Hôpitaux Universitaires de la Pitié-Salpêtrière-Charles Foix, Paris, France; Sorbonne Universités, UPMC Univ. Paris 06, INSERM, UMR_S 1166 and ICAN Institute for Cardiometabolism and Nutrition, Paris, France. 4. APHP, Centre de référence pour les maladies cardiaques héréditaires, Hôpital Pitié-Salpêtrière, Paris, France. 5. Service de Cardiologie, Centre Hospitalier Régional Universitaire Pontchaillou, Rennes, France. 6. Service de Cardiologie, CHU Dijon Bourgogne - Hôpital François Mitterrand, 2 bd Maréchal de Lattre de Tassigny, Dijon, France. 7. Service de Cardiologie, CHU de Nancy, Hôpitaux de Brabois, rue du Morvan, Vandoeuvre-lès-Nancy, France. 8. Service de Cardiologie, CHU de Poitiers, Poitiers, France. 9. APHP, Service Cardiologie, CHU Paris Nord- Val de Seine - Hôpital Xavier Bichat-Claude Bernard, Paris, France. 10. APHP, Service de Cardiologie, CHU Ambroise Paré, Boulogne Billancourt, France. 11. Centre de génétique et FHU TRANSLAD, Hôpital d'Enfants et Université de Bourgogne, Dijon, France. 12. Sorbonne Universités, UPMC Univ. Paris 06, INSERM, UMR_S 1166 and ICAN Institute for Cardiometabolism and Nutrition, Paris, France; APHP, Centre de référence pour les maladies cardiaques héréditaires, Hôpital Pitié-Salpêtrière, Paris, France. 13. Cardiology Department, APHM, La Timone Hospital, Marseille, France; Aix Marseille Univ, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille, France. Electronic address: gilbert.habib3@gmail.com.
Abstract
BACKGROUND: Few data exist concerning genotype-phenotype relationships in left ventricular noncompaction (LVNC). METHODS AND RESULTS: From a multicenter French Registry, we report the genetic and clinical spectrum of 95 patients with LVNC, and their genotype-phenotype relationship. Among the 95 LVNC, 45 had at least 1 mutation, including 14 cases of mutation in ion channel genes. In a complementary analysis including 16 additional patients with ion channel gene mutations, for a total of 30 patients with ion channel gene mutation, we found that those patients had higher median LV ejection fraction (60% vs 40%; P < .001) and more biventricular noncompaction (53.1% vs 18.5%; P < .001) than the 81 other patients with LVNC. Among them, both the 19 patients with an HCN4 mutation and the 11 patients with an RYR2 mutation presented with a higher LV ejection fraction and more frequent biventricular noncompaction than the 81 patients with LVNC but with no mutation in the ion channel gene, but only patients with HCN4 mutation presented with a lower heart rate. CONCLUSIONS: Ion channel gene mutations should be searched systematically in patients with LVNC associated with either bradycardia or biventricular noncompaction, particularly when LV systolic function is preserved. Identifying causative mutations is of utmost importance for genetic counselling of at-risk relatives of patients affected by LVNC.
BACKGROUND: Few data exist concerning genotype-phenotype relationships in left ventricular noncompaction (LVNC). METHODS AND RESULTS: From a multicenter French Registry, we report the genetic and clinical spectrum of 95 patients with LVNC, and their genotype-phenotype relationship. Among the 95 LVNC, 45 had at least 1 mutation, including 14 cases of mutation in ion channel genes. In a complementary analysis including 16 additional patients with ion channel gene mutations, for a total of 30 patients with ion channel gene mutation, we found that those patients had higher median LV ejection fraction (60% vs 40%; P < .001) and more biventricular noncompaction (53.1% vs 18.5%; P < .001) than the 81 other patients with LVNC. Among them, both the 19 patients with an HCN4 mutation and the 11 patients with an RYR2 mutation presented with a higher LV ejection fraction and more frequent biventricular noncompaction than the 81 patients with LVNC but with no mutation in the ion channel gene, but only patients with HCN4 mutation presented with a lower heart rate. CONCLUSIONS: Ion channel gene mutations should be searched systematically in patients with LVNC associated with either bradycardia or biventricular noncompaction, particularly when LV systolic function is preserved. Identifying causative mutations is of utmost importance for genetic counselling of at-risk relatives of patients affected by LVNC.