First-pass MR imaging in the assessment of perfusion impairment in patients with hypertrophic cardiomyopathy and the Asp175Asn mutation of the alpha-tropomyosin gene.
OBJECTIVE
To assess first-pass magnetic resonance (MR) imaging in the evaluation of perfusion impairment in a genetically homogeneous population of patients with hypertrophic cardiomyopathy (HCM) and the Asp175Asn mutation of the alpha-tropomyosin gene and to evaluate the association between hypertrophy and perfusion.


METHODS
Rest-stress first-pass MR imaging with gadopentetate dimeglumine was performed in 17 patients with HCM and the Asp175Asn substitution in the alpha-tropomyosin gene and in five control subjects. Global and segmental first-pass reserve index (FPR) measurements were derived from signal intensity versus time curves. Left ventricular (LV) wall thickness and LV mass index were measured on cine MR images. The Mann-Whitney test was used to evaluate the difference in FPR between the patient group and the control group. The Spearman correlation was used to evaluate the association between LV hypertrophy and FPR.


RESULTS
Global FPR was significantly lower in the patients with HCM than in the control subjects (1.12 +/- 0.35 vs 1.80 +/- 0.58, P =.015). In patients with HCM, maximal LV wall thickness and LV mass index correlated negatively with global FPR (r = -0.723, P =.001 and r = -0.598, P =.011, respectively). At the regional level, segmental FPR correlated inversely with LV wall thickness (r = -0.389; P <.001) in patients with HCM.


CONCLUSIONS
First-pass MR imaging facilitates global and regional evaluation of perfusion impairment in patients with HCM. The severity of perfusion impairment is associated with the degree of LV hypertrophy.
Sipola
Petri
P
Dept of Clin Radiology, Kuopio Univ Hosp, Puijonlaaksontie 2, 70210 Kuopio, Finland. petri.sipola@kuh.fi
Lauerma
Kirsi
K
Husso-Saastamoinen
Minna
M
Kuikka
Jyrki T
JT
Vanninen
Esko
E
Laitinen
Tomi
T
Manninen
Hannu
H
Niemi
Pekka
P
Peuhkurinen
Keijo
K
Jääskeläinen
Pertti
P
Laakso
Markku
M
Kuusisto
Johanna
J
Aronen
Hannu J
HJ
D000241:Adenosine; D000328:Adult; D002312:Cardiomyopathy, Hypertrophic / Q000235:genetics* / Q000503:physiopathology*; D017023:Coronary Angiography; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010477:Perfusion; D015203:Reproducibility of Results; D014335:Tropomyosin / Q000235:genetics*
D014335:Tropomyosin; D019786:Gadolinium DTPA; D000241:Adenosine