Resting "Solar Polar" map pattern and reduced apical flow reserve: characteristics of apical hypertrophic cardiomyopathy on SPECT myocardial perfusion imaging.
BACKGROUND
Patients with apical hypertrophic cardiomyopathy (ACM) are often referred for myocardial perfusion single photon emission computed tomography (SPECT) as a result of marked T-wave inversion and chest pain syndromes. Stress perfusion defects have been reported in ACM, but the characteristic SPECT pattern as well as the typical findings on volume-weighted polar maps has not been described.


RESULTS
Dual-isotope rest (thallium 201) and exercise or adenosine stress (technetium 99m tetrofosmin) myocardial perfusion SPECT was performed in 11 patients with ACM, including 8 with either normal coronary arteriography (n = 5) or a low pretest probability of coronary artery disease (CAD) (n = 3), and 14 control patients with concentric left ventricular hypertrophy. An 8-pixel-diameter circular region of interest was used to quantitatively compare apical and septal counts on CEqual volume-weighted polar maps. A characteristic "Solar Polar" map pattern resulting from the increased apical counts was present in each ACM patient at rest, with a mean apical-septal ratio of 1.39 +/- 0.17 (range, 1.23-1.62, P <.01 vs concentric left ventricular hypertrophy group). With stress, there was a significant decrease in the apical-septal ratio (0.96 +/- 0.18, P <.001 vs rest) in the ACM subgroup without CAD.


CONCLUSIONS
Patients with ACM demonstrate a newly described "Solar Polar" map pattern at rest, as well as relative apical ischemia on the stress images even in the absence of CAD.
Department of Medicine, University of Chicago, Chicago, IL 60637, USA. pward@medicine.bsd.uchicago.edu
R Parker
RP
Ward
Hemlata K
HK
Pokharna
Roberto M
RM
Lang
Kim A
KA
Williams
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D002312:Cardiomyopathy, Hypertrophic / Q000145:classification / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging*; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012146:Rest; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013793:Thallium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D018487:Ventricular Dysfunction, Left / Q000145:classification / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000209:etiology
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C027549:thallium chloride; C078700:technetium tc-99m tetrofosmin; D013793:Thallium