Left ventricular pseudoaneurysm: diagnosis by cine magnetic resonance imaging

We report a case that illustrates the difficulty in diagnosing left ventricular (LV) pseudoaneurysm and the potential value of cine magnetic resonance imaging (MRI). A 69-year-old man with a history of ischemic congestive heart failure had a mass found on routine chest X-ray, contiguous with the cardiac silhouette. Neither CT nor echocardiography accurately defined the mass. The diagnosis of LV pseudoaneurysm was definitely made by cine MRI. Although the accuracy of various imaging modalities for detecting LV pseudoaneurysm is not known, cine MRI was the most useful test in this case. Despite refusing surgery to correct the pseudoaneurysm, the patient survived for nearly 4 years, treated only with anticoagulation.     

Left ventricular non-compaction cardiomyopathy

In this article, we describe three patients with heart failure whose 2D echocardiograms showed left ventricular non-compaction cardiomyopathy characterized by prominent trabeculation with deep intertrabecular spaces in the myocardium.     

Left ventricular remodeling with age in normal men versus women: novel insights using three-dimensional magnetic resonance imaging

Echocardiographic left ventricular (LV) wall thickness increases with age, suggesting LV hypertrophy. However, autopsy studies have shown no change, or even a decrease, in LV mass with age. With many pathologies, LV remodeling results in changes in ventricular shape. Age-associated LV shape change might explain this discrepancy, although this has not been studied. Magnetic resonance imaging (MRI) was used in 336 healthy, normotensive adults (mean age 56 +/- 18 years; 200 women, 136 men) to measure LV mass, end-diastolic LV wall thickness, length, diameter, and shape. Echocardiographic LV mass was measured in a subset of 86 subjects by a standard algorithm. In women, LV wall thickness increased by 14% (r = 0.19, p <0.02), whereas LV length decreased by 9% (r = -0.26, p = 0.0006); LV diameter was unchanged. Thus, LV mass did not vary with age (r -0.04, p = 0.06) and the sphericity index decreased (r = -0.165, p <0.05). In men, LV wall thickness and diameter were unrelated to age, but there was an 11% decrease in LV length (r = -0.29, p = 0.003); therefore, there was an 11% decrease in LV mass (r = -0.20, p = 0.019) and a decrease in the sphericity index (r = -0.218, p <0.04). No change occurred in echocardiographic LV mass with age in either gender, although echocardiographic LV wall thickness increased in both. The left ventricle becomes more spherical with age in normal adults due to reduced LV length. In women, increased LV wall thickness offsets the decreasing LV length, whereas in men, LV wall thickness fails to compensate, resulting in decreased LV mass with age.     

Left ventricular volume measured rapidly by oblique magnetic resonance imaging

Magnetic resonance measurements of left ventricular volume and ejection fraction based on measurements of area and length in a single oblique plane containing the long axis of the ventricle were compared with measurements made by summing the areas of the chamber in multiple contiguous slices. The multislice technique is known to be accurate, but the single slice technique is much quicker; it takes only nine minutes of acquisition time for both volume and ejection fraction. In 25 normal subjects there was good agreement between the two methods of measuring volume with a mean (SD) difference between measurements of 2.0 (6.6) ml. In 20 patients with previous infarction it was less good with a mean (SD) difference of 4.5 (18.1) ml. The mean (SD) difference of ejection fraction measurements was -0.019 (0.038) in the normal subjects and -0.059 (0.106) in the patients, and the discrepancy between the two techniques was greatest in the patients with a pronounced abnormality of wall motion and low ejection fraction. In a further 25 normal subjects, the agreement between single plane volume measurements in the vertical and horizontal long axis planes was good, indicating that either plane is suitable for rapid measurement. Single plane measurements of left ventricular volume and ejection fraction can be made with the accuracies stated, which are sufficient for routine clinical use except in patients with a pronounced abnormality of wall motion. In combination with measurements of regional wall thickness and motion, previously described, the technique offers a rapid non-invasive assessment of both global and regional left ventricular function.     

Contrast-enhanced cardiovascular magnetic resonance imaging of right ventricular infarction.

OBJECTIVES: We assessed the role of late enhancement cardiovascular magnetic resonance imaging (LE-CMR) for the diagnosis of right ventricular infarction (RVI). BACKGROUND: Right ventricular infarction occurs in about one-half of patients with inferior myocardial infarction (MI). It is associated with an unfavorable prognosis, but established methods often lack the diagnostic accuracy to detect it. Late enhancement cardiovascular magnetic resonance imaging accurately detects left ventricular MI. METHODS: Thirty-seven patients with acute inferior MI were included. To test for RVI, they prospectively underwent a physical examination, an electrocardiogram (ECG) for ST-segment elevation in the V4r right precordial lead, and an echocardiogram. After coronary reperfusion, LE-CMR was performed for assessing presence and extent of late enhancement in the right ventricular (RV) wall. The LE-CMR data were compared with the other results; interobserver variability was assessed. The LE-CMR was repeated after 13 months. RESULTS: Late enhancement cardiovascular magnetic resonance imaging detected RVI in 21 of 37 (57%) patients with acute inferior MI. Interobserver variability was very good (kappa 0.83); physical exam was positive for RVI in 7 of 37 (19%) patients, V4r ECG in 13 of 37 (35%) patients, and echocardiogram in 6 of 37 (16%) patients. The LE-CMR findings for RVI showed only mild agreement with findings for RVI on physical exam (kappa 0.30), V(4)r ECG (kappa 0.38), and echocardiography (kappa 0.32). Irreversible injury of the RV persisted at 13 months (kappa 0.85). CONCLUSIONS: In patients with acute inferior MI, RVI is more frequently detected by LE-CMR than by current standard diagnostic techniques. Further CMR studies might allow for analyzing its clinical and prognostic relevance.     

Left ventricular volume measured rapidly by oblique magnetic resonance imaging.

Magnetic resonance measurements of left ventricular volume and ejection fraction based on measurements of area and length in a single oblique plane containing the long axis of the ventricle were compared with measurements made by summing the areas of the chamber in multiple contiguous slices. The multislice technique is known to be accurate, but the single slice technique is much quicker; it takes only nine minutes of acquisition time for both volume and ejection fraction. In 25 normal subjects there was good agreement between the two methods of measuring volume with a mean (SD) difference between measurements of 2.0 (6.6) ml. In 20 patients with previous infarction it was less good with a mean (SD) difference of 4.5 (18.1) ml. The mean (SD) difference of ejection fraction measurements was -0.019 (0.038) in the normal subjects and -0.059 (0.106) in the patients, and the discrepancy between the two techniques was greatest in the patients with a pronounced abnormality of wall motion and low ejection fraction. In a further 25 normal subjects, the agreement between single plane volume measurements in the vertical and horizontal long axis planes was good, indicating that either plane is suitable for rapid measurement. Single plane measurements of left ventricular volume and ejection fraction can be made with the accuracies stated, which are sufficient for routine clinical use except in patients with a pronounced abnormality of wall motion. In combination with measurements of regional wall thickness and motion, previously described, the technique offers a rapid non-invasive assessment of both global and regional left ventricular function.     

Left ventricular mass quantitation using single-phase cardiac magnetic resonance imaging.

Magnetic resonance imaging (MRI) has been used to measure left ventricular (LV) mass in animals with superior accuracy. However, its use in cardiac patients has been limited by the long total scan times necessitated by imaging the heart at end-diastole at each of 8 to 10 slice locations. Recent canine studies showed that LV mass may be determined accurately, with considerable timesavings, by use of sequential images throughout the cardiac cycle (single-phase MRI). Twenty normal subjects underwent spin-echo MRI to determine the relationship between LV mass computed from single-phase MRI and results obtained from the more time-consuming end-diastolic MRI (which was used as the reference standard for this study). The left ventricle was spanned with 2 interleaved series of 5 short-axis 1 cm thick slices. 5 images, evenly spaced throughout the cardiac cycle, were obtained at each slice location in all subjects. LV mass ranged from 86 to 198 g. Although end-diastolic LV mass exceeded single-phase results by an average of 5 g (p less than 0.002), there was a close correlation between the 2 (slope = 0.99; r = 0.96). Although LV mass derived from end-diastolic images exceeded single-phase results, this difference is unlikely to be clinically significant and is small compared with the standard error of echocardiographic methods. Furthermore, when the order in which single-phase images were selected was reversed, there was improved agreement with end-diastolic MRI.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gender-specific differences in left ventricular remodelling and fibrosis in hypertrophic cardiomyopathy: insights from cardiovascular magnetic resonance

BACKGROUND: Gender is an independent risk factor for heart failure mortality in hypertrophic cardiomyopathy (HCM). AIMS: To explore the interaction between gender, myocardial fibrosis and remodelling in HCM. METHODS: We studied 64 HCM patients (28 females, aged 51+/-16 years) categorized as non-obstructive (HNCM, n=31) or obstructive (HOCM, n=33) and 60 healthy subjects (31 females, aged 43+/-14 years). Cine imaging was performed to assess left ventricular volumes and mass. LV remodelling index (LVRI) was calculated. Extension of late gadolinium enhancement (LGE) was quantified. RESULTS: Females in the control group and in the HNCM group had a lower LVRI than males (control: 0.7+/-0.1 vs. 0.9+/-0.2 g/ml, p<0.002; HNCM: 1.1+/-0.2 vs. 1.5+/-0.5 g/ml, p<0.001). In contrast, HOCM females had a similar LVRI compared to males (1.8+/-0.5 vs. 1.7+/-0.4 g/ml, p=ns). Thus the increase in LVRI was more pronounced in females compared to males. LGE was noted in 70% of the patients. No relation was found between the presence or the quantity of myocardial fibrosis and gender in any of the patient subgroups. CONCLUSION: Our data suggest a disproportionate degree of remodelling in different forms of HCM depending on gender. Gender does not appear to influence the quantity of fibrosis as defined by LGE.