Prognostic utility of cardiovascular magnetic resonance upright maximal treadmill exercise testing.

BACKGROUND: Left ventricular wall motion abnormalities (LVWMA) observed during cardiovascular magnetic resonance (CMR) pharmacologic stress testing can be used to determine cardiac prognosis, but currently, information regarding the prognostic utility of upright maximal treadmill induced LVWMA is unknown. Our objective was to determine the prognostic utility of upright maximal treadmill exercise stress CMR. METHODS: One hundred and fifteen (115) men and women with known or suspected coronary arteriosclerosis and an appropriate indication for cardiovascular (CV) imaging to supplement ST segment stress testing underwent an upright treadmill exercise CMR stress test in which LVWMA were identified before and immediately after exercise. Personnel blinded to results determined the post-test incidence of cardiac events (cardiac death, myocardial infarctions [MI], and unstable angina warranting hospital admission or coronary arterial revascularization). RESULTS: All participants completed the testing protocol, with 90% completing image acquisition within 60 s of exercise cessation. MI or cardiac death occurred in 3% of individuals without and 17% of individuals with inducible LVWMA (p = 0.024). The combination of MI, cardiac death, and unstable angina warranting hospitalization occurred in 14% of individuals without and 47% of individuals with inducible LVWMA (p = 0.002). The addition of CMR imaging identified those at risk for future events (p = 0.002), as opposed to the electrocardiogram stress test alone (p = 0.63). CONCLUSIONS: In patients with or suspected of coronary arteriosclerosis and appropriate indication for imaging to supplement ST segment analysis during upright treadmill exercise, the presence of inducible LVWMA during treadmill exercise stress CMR supplements ST segment monitoring and helps identify those at risk of the future combined endpoints of myocardial infarction, cardiac death, and unstable angina warranting hospitalization.

Quantitative measurement of mitral regurgitation: comparison between echocardiography and cardiac magnetic resonance imaging.

BACKGROUND AND OBJECTIVE: Echocardiography is usually performed to quantify the severity of regurgitation. Magnetic resonance imaging (MRI) can also quantify mitral regurgitation. This study was performed to determine whether MRI can reliably quantify the severity of mitral regurgitation when compared with echocardiography MATERIAL AND METHOD: The authors retrospectively studied patients who underwent cardiac MRI between January 2008 and January 2011. Echocardiography was performed within 3 months of MRI. Mitral regurgitation was quantified by 3 methods of MRI; 1) difference of left ventricular stroke volume and right ventricular stroke volume, 2) difference of left ventricular stroke volume and forward flow volume in ascending aorta and 3) calculation of regurgitation fraction from the ratio of area of regurgitantjet and area of the left atrium. Proximal isovelocity surface area was the echocardiography parameter for mitral regurgitation. RESULTS: Forty-three subjects (24 women and 19 men; 47 to 85 years of age) were enrolled. Mitral regurgitation grading by MRI (2nd method) was mild (n = 28) moderate (n = 11) and severe (n = 4). There was moderate correlation between echocardiography and MRI assessments of regurgitation volume as follows; (1) difference between left ventricular stroke volume and right ventricular stroke volume (r = 0.48, p = 0.016), (2) subtracting forward flow volume of ascending aorta from left ventricular stroke volume (r = 0.48, p = 0.012). There was also correlation between regurgitation volume by echocardiography and fraction of maximal area of regurgitant jet divided by the area of the left atrium (r = 0.72, p < 0.001). CONCLUSION: Cardiac MRI compares favorably with echocardiography for quantifying mitral regurgitation severity.

Frequency of Left Ventricular End-Diastolic Volume-Mediated Declines in Ejection Fraction in Patients Receiving Potentially Cardiotoxic Cancer Treatment.

We sought to determine the frequency by which decreases in left ventricular (LV) end-diastolic volume (LVEDV) with and without increases in end-systolic volume (LVESV) influenced early cancer treatment-associated declines in LV ejection fraction (LVEF) or LV mass. One hundred twelve consecutively recruited subjects (aged 52 ± 14 years) with cancer underwent blinded cardiovascular magnetic resonance measurements of LV volumes, mass, and LVEF before and 3 months after initiating potentially cardiotoxic chemotherapy (72% of participants received anthracyclines). Twenty-six participants developed important declines in LVEF of >10% or to values <50% at 3 months, in whom 19% versus 60%, respectively, experienced their decline in LVEF due to isolated declines in LVEDV versus an increase in LVESV; participants who dropped their LVEF due to decreases in LVEDV lost more LV mass than those who dropped their LVEF due to an increase in LVESV (p = 0.03). Nearly one fifth of subjects experience marked LVEF declines due to an isolated decline in LVEDV after initiating potentially cardiotoxic chemotherapy. Because reductions in intravascular volume (which could be treated by volume repletion) may account for LVEDV-related declines in LVEF, these data indicate that LV volumes should be reviewed along with LVEF when acquiring imaging studies for cardiotoxicity during the treatment for cancer.