title: Evaluation of apical subtype of hypertrophic cardiomyopathy using cardiac magnetic resonance imaging with gadolinium enhancement.
abstract: Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of HC. We sought to characterize cardiac magnetic resonance imaging (MRI) findings among apical HC patients. This was a retrospective review of consecutive patients with a diagnosis of apical HC who underwent cardiac MRI examinations at the Mayo Clinic (Rochester, MN) from August 1999 to October 2011. Clinical and demographic data at the time of cardiac MRI study were abstracted. Cardiac MRI study and 2-dimensional echocardiograms performed within 6 months of the cardiac MRI were reviewed; 96 patients with apical HC underwent cardiac MRI examinations. LV end-diastolic and end-systolic volumes were 130.7 ± 39.1 ml and 44.2 ± 20.9 ml, respectively. Maximum LV thickness was 19 ± 5 mm. Hypertrophy extended beyond the apex into other segments in 57 (59.4%) patients. Obstructive physiology was seen in 12 (12.5%) and was more common in the mixed apical phenotype than the pure apical (19.3 vs 2.6%, p = 0.02). Apical pouches were noted in 39 (40.6%) patients. Late gadolinium enhancement (LGE) was present in 70 (74.5%) patients. LGE was associated with severe symptoms and increased maximal LV wall thickness. In conclusion, cardiac MRI is well suited for studying the apical form of HC because of difficulty imaging the cardiac apex with standard echocardiography. Cardiac MRI is uniquely suited to delineate the presence or absence of an apical pouch and abnormal myocardial LGE that may have implications in the natural history of apical HM. In particular, the presence of abnormal LGE is associated with clinical symptoms and increased wall thickness.
authors.affiliation: Division of Internal Medicine, Mayo Clinic, Rochester, Minnesota. Electronic address: kebed.kalie@mayo.edu.
authors.forename: Kalie Y
authors.initials: KY
authors.lastname: Kebed
authors.affiliation: Division of Internal Medicine, St. Joseph's Hospital, Phoenix, Arizona.
authors.forename: Raed I
authors.initials: RI
authors.lastname: Al Adham
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Kalkidan
authors.initials: K
authors.lastname: Bishu
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: J Wells
authors.initials: JW
authors.lastname: Askew
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Kyle W
authors.initials: KW
authors.lastname: Klarich
authors.affiliation: Division of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Araoz
authors.affiliation: Division of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Foley
authors.affiliation: Division of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: James F
authors.initials: JF
authors.lastname: Glockner
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Rick A
authors.initials: RA
authors.lastname: Nishimura
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Nandan S
authors.initials: NS
authors.lastname: Anavekar
mesh_terms: D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis*; D003287:Contrast Media; D015716:Electrocardiography, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D019786:Gadolinium DTPA; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA