EFFECT OF REGIONAL MYOCARDIAL PERFUSION ABNORMALITIES ON REGIONAL MYOCARDIAL EARLY DIASTOLIC FUNCTION IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY

Nonuniform hypertrophy of the left ventricle is an important factor in regional diastolic dysfunction in patients with hypertrophic cardiomy opathy (HCM). However, the effect of myocardial perfusion abnormalitie s on regional diastolic dysfunction has not been established in patien ts with HCM. We investigated the relationship between regional myocard ial perfusion abnormalities and regional early diastolic function in 3 1 patients with HCM and 8 control patients. Short-axis images of the l eft ventricle recorded by cine magnetic resonance imaging were divided into ten blocks. The time-to-peak-wall-thickness-thinning rate (TPWR) and the wall thickness were measured in each block. Of the 310 blocks from the patients with HCM, 242 (78%) showed normal thallium-201 upta ke (group 1), 40 (13%) showed slightly decreased uptake (group 2), and 28 (9%) showed markedly decreased uptake (group 3). There was no diff erence in the regional wall thickness among the three groups. The TPWR was longer in patients with HCM than in control patients. It was sign ificantly longer in group 3 (190 +/- 45ms) than in group 1 (167 +/- 36 ms) and group 2 (160 +/- 31ms). (P < 0.01). The linear regression slop e of the relationship between the TPWR and the regional wall thickness was significantly steeper in group 3 than in groups 1 and 2 (P < 0.05 ). In conclusion, abnormalities in regional myocardial perfusion, in a ddition to regional hypertrophy, contributed to the regional early dia stolic dysfunction in patients with HCM.