PET abnormalities in patients with nonischemic cardiomyopathy.
BACKGROUND
The abnormalities in dilated cardiomyopathy (DCM) are generally considered diffuse and to affect the left ventricle in a global manner. However, regional wall motion abnormalities and metabolic defects may also occur to varying, but unclear degrees. QRS width and metabolic defects on positron emission tomography (PET) correlate with survival. We sought to ascertain the prevalence of regional defects in DCM by multiple imaging modalities and to establish the relationship between QRS width and these defects.


METHODS
In consecutive patients with advanced nonischemic DCM, undergoing cardiac transplant evaluation, we reviewed multiple imaging modalities (PET, 2-dimensional echocardiography, and radionuclide ventriculography) to quantify the incidence of regional metabolic and wall motion abnormalities and correlate them with clinical and electrocardiographic parameters.


RESULTS
Of 44 patients studied, PET imaging revealed scar in 91% of patients, with a mean of 25 +/- 18% of the left ventricle involved, predominantly in the distribution of the left anterior descending artery. Regional wall motion abnormalities occurred in 51% of patients who underwent echocardiography and 59% of patients who underwent nuclear scintigraphy (with only 70% concordance). QRS duration on the surface electrocardiogram correlated positively with the degree of scarring (r=.52, P=.0007).


CONCLUSIONS
The presence of scar (matched perfusion and metabolic defects) on PET scanning in patients with advanced DCM is not always indicative of coronary disease. Thus coronary angiography is usually required to define the etiology of systolic dysfunction. The extent of scar correlates with QRS duration. This may have implications for the application of cardiac resynchronization therapy.
O'Neill
James O
JO
Kaufman Center for Heart Failure, Department of Cardiovascular Medicine and Cardiothoracic Surgery, Cleveland Clinic Foundation, Ohio 44195, USA.
McCarthy
Patrick M
PM
Brunken
Richard C
RC
Buda
Tiffany
T
Hoercher
Katherine
K
Young
James B
JB
Starling
Randall C
RC
D000328:Adult; D000368:Aged; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004452:Echocardiography; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012414:Rubidium Radioisotopes; D014055:Tomography, Emission-Computed; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology
D019275:Radiopharmaceuticals; D012414:Rubidium Radioisotopes; D019788:Fluorodeoxyglucose F18