Author + information
- Kalie Yang Kebed,
- Raed Al Adham,
- Kalkidan Bishu,
- John Askew,
- Kyle Klarich,
- Philip Araoz,
- Thomas Foley,
- James Glockner,
- Rick Nishimura,
- Steve Ommen and
- Nandan Anavekar
Cardiac MRI (CMR) is emerging as a valuable imaging modality in the accurate diagnosis and risk stratification of patients with hypertrophic cardiomyopathy (HCM). CMR is better suited for studying the apical form of HCM due to difficulty imaging the cardiac apex with standard echocardiography. We sought to characterize CMR findings among apical HCM patients.
This was a retrospective review of consecutive HCM patients with a diagnosis of apical HCM who underwent CMR exams at Mayo Clinic from August 1999 to October 2011. Demographics, comorbidities, and CMR data were abstracted from electronic medical records.
Ninety-six apical HCM patients underwent CMR examinations, two without gadolinium contrast. Mean age was 55 ± 18 years, 68% were male, 88% were Caucasian, and 19% had a first-degree relative with HCM. Comorbidities included hypertension (45%), diabetes mellitus (3%), atrial fibrillation (16%) and coronary artery disease (17%). Syncope was reported in 12% while 30% had severe symptoms (NYHA III and IV). On CMR, ejection fraction was 66 ± 9%. LV end-diastolic and end-systolic volumes were 131 ± 39 ml and 44 ± 21 ml, respectively. Hypertrophy extended beyond the LV apex into other segments in 59%. Maximum LV thickness was 19 ± 5 mm. Obstructive physiology was seen in 13%. Apical pouches were noted in 41%, with thrombus in 3%. Late gadolinium enhancement (LGE) was present in 73%. Hypertension was less common among HCM patients with LGE (35 vs 72%, compared to those without LGE, p=0.002). Severe symptoms were more common among those with LGE (36 vs 12%, p=0.02). LGE was also associated with increased LV maximal thickness (20 ± 5 mm vs 16 ± 4 mm among those without LGE, p <0.001) and the presence of apical pouches (46 vs 20%, p=0.03).
Among a series of patients with the apical subtype of HCM, CMR was useful in detecting apical pouches and LGE. Further, we show that LGE is associated with severe symptoms, LV thickness, and apical pouches. CMR provides phenotypic characterization that is useful for risk stratification in apical HCM.
Poster Sessions, Expo North
Sunday, March 10, 2013, 3:45 p.m.-4:30 p.m.
Session Title: Imaging: MRI V – CMR in Hypertrophic and Infiltrative Cardiomyopathies
Abstract Category: 19. Imaging: MRI
Presentation Number: 1272-367
- 2013 American College of Cardiology Foundation