Do myocardial perfusion SPECT and radionuclide angiography studies in adult patients with hypertrophic cardiomyopathy have prognostic implications?
BACKGROUND
Some myocardial perfusion single photon emission computed tomography (SPECT) and radionuclide ventriculography studies have suggested that the presence of regional perfusion defects and diastolic abnormalities could have prognostic implications in patients with hypertrophic cardiomyopathy (HC). The aim of this prospective study was to analyze the prognostic value of these techniques in adult patients with HC.


RESULTS
One hundred one patients with HC (44 women; mean age, 54 +/- 16 years; 55% obstructive) were prospectively studied by means of myocardial perfusion SPECT and radionuclide angiography. Of these patients, 55 (54.4%) had an abnormal myocardial perfusion SPECT study: 28 (27.7%) had fixed defects and 41 (40.6%) had reversible defects; 15 (14.8%) of these patients had both types of defect. Of the patients, 16% had left ventricular ejection fraction lower than 60%, 25.7% had an abnormal peak filling rate, and 51% had an abnormal time to peak filling rate. During 5.6 +/- 2.7 years of follow-up, 13 patients (12.8%) died (heart failure 8 and sudden death in 5) and 14 had one or more severe complications develop (syncope in 6, angina III-IV in 4, dyspnea III-IV in 10, and acute myocardial infarction in 3). The summed difference score was higher in patients with cardiac death (2.2 +/- 2.3 vs 1.1 +/- 1.3, P = .008), and fixed defects were more prevalent in patients with severe complications (57% vs 21%, P = .01). In the Kaplan-Meier survival plot analysis, severe complications were more likely in patients with fixed defects (P = .01) or ejection fraction lower than 60% ( P = .01).


CONCLUSIONS
Prognostic information from myocardial perfusion SPECT and radionuclide angiography has limited clinical significance with regard to cardiac death in adult patients with HC. However, the presence of fixed defects and lower ejection fraction in these patients has an adverse prognostic meaning for severe complications.
Department of Cardiology, Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain.
Guillermo
G
Romero-Farina
Jaume
J
Candell-Riera
Enrique
E
Galve
Lluís
L
Armadans
Francisca
F
Ramos
Joan
J
Castell
Santiago
S
Aguadé
Juan M
JM
Nogales
Jordi
J
Soler-Soler
D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging* / Q000401:mortality*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011379:Prognosis; D011875:Radionuclide Angiography / Q000706:statistics & numerical data*; D019275:Radiopharmaceuticals; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D016019:Survival Analysis; D015899:Tomography, Emission-Computed, Single-Photon / Q000706:statistics & numerical data*
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin